| 1. |
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| 2. |
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| 3. |
- Aad, G, et al.
(författare)
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- 2014
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Ingår i: Physical Review Letters. - 1079-7114 .- 0031-9007. ; 113:17
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Tidskriftsartikel (refereegranskat)
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| 4. |
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| 5. |
- Palmer, Nicholette D, et al.
(författare)
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A genome-wide association search for type 2 diabetes genes in African Americans.
- 2012
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Ingår i: PloS one. - San Francisco : Public Library of Science (PLoS). - 1932-6203. ; 7:1, s. e29202-
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Tidskriftsartikel (refereegranskat)abstract
- African Americans are disproportionately affected by type 2 diabetes (T2DM) yet few studies have examined T2DM using genome-wide association approaches in this ethnicity. The aim of this study was to identify genes associated with T2DM in the African American population. We performed a Genome Wide Association Study (GWAS) using the Affymetrix 6.0 array in 965 African-American cases with T2DM and end-stage renal disease (T2DM-ESRD) and 1029 population-based controls. The most significant SNPs (n = 550 independent loci) were genotyped in a replication cohort and 122 SNPs (n = 98 independent loci) were further tested through genotyping three additional validation cohorts followed by meta-analysis in all five cohorts totaling 3,132 cases and 3,317 controls. Twelve SNPs had evidence of association in the GWAS (P<0.0071), were directionally consistent in the Replication cohort and were associated with T2DM in subjects without nephropathy (P<0.05). Meta-analysis in all cases and controls revealed a single SNP reaching genome-wide significance (P<2.5×10(-8)). SNP rs7560163 (P = 7.0×10(-9), OR (95% CI) = 0.75 (0.67-0.84)) is located intergenically between RND3 and RBM43. Four additional loci (rs7542900, rs4659485, rs2722769 and rs7107217) were associated with T2DM (P<0.05) and reached more nominal levels of significance (P<2.5×10(-5)) in the overall analysis and may represent novel loci that contribute to T2DM. We have identified novel T2DM-susceptibility variants in the African-American population. Notably, T2DM risk was associated with the major allele and implies an interesting genetic architecture in this population. These results suggest that multiple loci underlie T2DM susceptibility in the African-American population and that these loci are distinct from those identified in other ethnic populations.
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| 6. |
- Speliotes, Elizabeth K., et al.
(författare)
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Association analyses of 249,796 individuals reveal 18 new loci associated with body mass index
- 2010
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Ingår i: Nature Genetics. - : Springer Science and Business Media LLC. - 1061-4036 .- 1546-1718. ; 42:11, s. 937-948
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Tidskriftsartikel (refereegranskat)abstract
- Obesity is globally prevalent and highly heritable, but its underlying genetic factors remain largely elusive. To identify genetic loci for obesity susceptibility, we examined associations between body mass index and ~2.8 million SNPs in up to 123,865 individuals with targeted follow up of 42 SNPs in up to 125,931 additional individuals. We confirmed 14 known obesity susceptibility loci and identified 18 new loci associated with body mass index (P < 5 × 10−8), one of which includes a copy number variant near GPRC5B. Some loci (at MC4R, POMC, SH2B1 and BDNF) map near key hypothalamic regulators of energy balance, and one of these loci is near GIPR, an incretin receptor. Furthermore, genes in other newly associated loci may provide new insights into human body weight regulation.
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| 7. |
- Assimes, Themistocles L., et al.
(författare)
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Lack of Association Between the Trp719Arg Polymorphism in Kinesin-Like Protein-6 and Coronary Artery Disease in 19 Case-Control Studies
- 2010
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Ingår i: Journal of the American College of Cardiology. - : Elsevier BV. - 0735-1097. ; 56:19, s. 1552-1563
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Tidskriftsartikel (refereegranskat)abstract
- Objectives We sought to replicate the association between the kinesin-like protein 6 (KIF6) Trp719Arg polymorphism (rs20455), and clinical coronary artery disease (CAD). Background Recent prospective studies suggest that carriers of the 719Arg allele in KIF6 are at increased risk of clinical CAD compared with noncarriers. Methods The KIF6 Trp719Arg polymorphism (rs20455) was genotyped in 19 case-control studies of nonfatal CAD either as part of a genome-wide association study or in a formal attempt to replicate the initial positive reports. Results A total of 17,000 cases and 39,369 controls of European descent as well as a modest number of South Asians, African Americans, Hispanics, East Asians, and admixed cases and controls were successfully genotyped. None of the 19 studies demonstrated an increased risk of CAD in carriers of the 719Arg allele compared with noncarriers. Regression analyses and fixed-effects meta-analyses ruled out with high degree of confidence an increase of >= 2% in the risk of CAD among European 719Arg carriers. We also observed no increase in the risk of CAD among 719Arg carriers in the subset of Europeans with early-onset disease (younger than 50 years of age for men and younger than 60 years of age for women) compared with similarly aged controls as well as all non-European subgroups. Conclusions The KIF6 Trp719Arg polymorphism was not associated with the risk of clinical CAD in this large replication study. (J Am Coll Cardiol 2010;56:1552-63) (C) 2010 by the American College of Cardiology Foundation
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| 8. |
- Schunkert, Heribert, et al.
(författare)
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Large-scale association analysis identifies 13 new susceptibility loci for coronary artery disease
- 2011
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Ingår i: Nature Genetics. - : Springer Science and Business Media LLC. - 1546-1718 .- 1061-4036. ; 43:4, s. 153-333
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Tidskriftsartikel (refereegranskat)abstract
- We performed a meta-analysis of 14 genome-wide association studies of coronary artery disease (CAD) comprising 22,233 individuals with CAD (cases) and 64,762 controls of European descent followed by genotyping of top association signals in 56,682 additional individuals. This analysis identified 13 loci newly associated with CAD at P < 5 x 10(-8) and confirmed the association of 10 of 12 previously reported CAD loci. The 13 new loci showed risk allele frequencies ranging from 0.13 to 0.91 and were associated with a 6% to 17% increase in the risk of CAD per allele. Notably, only three of the new loci showed significant association with traditional CAD risk factors and the majority lie in gene regions not previously implicated in the pathogenesis of CAD. Finally, five of the new CAD risk loci appear to have pleiotropic effects, showing strong association with various other human diseases or traits.
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| 9. |
- Voight, Benjamin F, et al.
(författare)
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Plasma HDL cholesterol and risk of myocardial infarction : a mendelian randomisation study
- 2012
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Ingår i: The Lancet. - 0140-6736 .- 1474-547X. ; 380:9841, s. 572-580
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: High plasma HDL cholesterol is associated with reduced risk of myocardial infarction, but whether this association is causal is unclear. Exploiting the fact that genotypes are randomly assigned at meiosis, are independent of non-genetic confounding, and are unmodified by disease processes, mendelian randomisation can be used to test the hypothesis that the association of a plasma biomarker with disease is causal.METHODS: We performed two mendelian randomisation analyses. First, we used as an instrument a single nucleotide polymorphism (SNP) in the endothelial lipase gene (LIPG Asn396Ser) and tested this SNP in 20 studies (20,913 myocardial infarction cases, 95,407 controls). Second, we used as an instrument a genetic score consisting of 14 common SNPs that exclusively associate with HDL cholesterol and tested this score in up to 12,482 cases of myocardial infarction and 41,331 controls. As a positive control, we also tested a genetic score of 13 common SNPs exclusively associated with LDL cholesterol.FINDINGS: Carriers of the LIPG 396Ser allele (2·6% frequency) had higher HDL cholesterol (0·14 mmol/L higher, p=8×10(-13)) but similar levels of other lipid and non-lipid risk factors for myocardial infarction compared with non-carriers. This difference in HDL cholesterol is expected to decrease risk of myocardial infarction by 13% (odds ratio [OR] 0·87, 95% CI 0·84-0·91). However, we noted that the 396Ser allele was not associated with risk of myocardial infarction (OR 0·99, 95% CI 0·88-1·11, p=0·85). From observational epidemiology, an increase of 1 SD in HDL cholesterol was associated with reduced risk of myocardial infarction (OR 0·62, 95% CI 0·58-0·66). However, a 1 SD increase in HDL cholesterol due to genetic score was not associated with risk of myocardial infarction (OR 0·93, 95% CI 0·68-1·26, p=0·63). For LDL cholesterol, the estimate from observational epidemiology (a 1 SD increase in LDL cholesterol associated with OR 1·54, 95% CI 1·45-1·63) was concordant with that from genetic score (OR 2·13, 95% CI 1·69-2·69, p=2×10(-10)).INTERPRETATION: Some genetic mechanisms that raise plasma HDL cholesterol do not seem to lower risk of myocardial infarction. These data challenge the concept that raising of plasma HDL cholesterol will uniformly translate into reductions in risk of myocardial infarction.
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| 10. |
- Allan, Eric, et al.
(författare)
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Interannual variation in land-use intensity enhances grassland multidiversity
- 2014
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Ingår i: Proceedings of the National Academy of Sciences. - : Proceedings of the National Academy of Sciences. - 1091-6490 .- 0027-8424. ; 111:1, s. 308-313
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Tidskriftsartikel (refereegranskat)abstract
- Although temporal heterogeneity is a well-accepted driver of biodiversity, effects of interannual variation in land-use intensity (LUI) have not been addressed yet. Additionally, responses to land use can differ greatly among different organisms; therefore, overall effects of land-use on total local biodiversity are hardly known. To test for effects of LUI (quantified as the combined intensity of fertilization, grazing, and mowing) and interannual variation in LUI (SD in LUI across time), we introduce a unique measure of whole-ecosystem biodiversity, multidiversity. This synthesizes individual diversity measures across up to 49 taxonomic groups of plants, animals, fungi, and bacteria from 150 grasslands. Multidiversity declined with increasing LUI among grasslands, particularly for rarer species and aboveground organisms, whereas common species and belowground groups were less sensitive. However, a high level of interannual variation in LUI increased overall multidiversity at low LUI and was even more beneficial for rarer species because it slowed the rate at which the multidiversity of rare species declined with increasing LUI. In more intensively managed grasslands, the diversity of rarer species was, on average, 18% of the maximum diversity across all grasslands when LUI was static over time but increased to 31% of the maximum when LUI changed maximally over time. In addition to decreasing overall LUI, we suggest varying LUI across years as a complementary strategy to promote biodiversity conservation.
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| 11. |
- Ledoux, X., et al.
(författare)
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The Neutrons for Science Facility at SPIRAL-2
- 2014
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Ingår i: Nuclear Data Sheets. - : Elsevier BV. - 0090-3752 .- 1095-9904. ; 119, s. 353-356
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Tidskriftsartikel (refereegranskat)abstract
- The Neutrons For Science (NFS) facility is a component of SPIRAL-2 laboratory under construction at Caen (France). SPIRAL-2 is dedicated to the production of high intensity Radioactive Ions Beams (RIB). It is based on a high-power linear accelerator (LINAG) to accelerate deuterons beams in order to produce neutrons by breakup reactions on a C converter. These neutrons will induce fission in U-238 for production of radioactive isotopes. Additionally to the RIB production, the proton and deuteron beams delivered by the accelerator will be used in the NFS facility. NFS is composed of a pulsed neutron beam and irradiation stations for cross-section measurements and material studies. The beams delivered by the LINAG will allow producing intense neutron beams in the 100 keV-40 MeV energy range with either a continuous or quasi-mono-energetic spectrum. At NFS available average fluxes will be up to 2 orders of magnitude higher than those of other existing time-of-flight facilities in the 1 MeV - 40 MeV range. NFS will be a very powerful tool for fundamental physics and application related research in support of the transmutation of nuclear waste, design of future fission and fusion reactors, nuclear medicine or test and development of new detectors. The facility and its characteristics are described, and several examples of the first potential experiments are presented.
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| 12. |
- Yang, Jian, et al.
(författare)
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FTO genotype is associated with phenotypic variability of body mass index
- 2012
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Ingår i: Nature. - : Springer Science and Business Media LLC. - 0028-0836 .- 1476-4687. ; 490:7419, s. 267-272
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Tidskriftsartikel (refereegranskat)abstract
- There is evidence across several species for genetic control of phenotypic variation of complex traits(1-4), such that the variance among phenotypes is genotype dependent. Understanding genetic control of variability is important in evolutionary biology, agricultural selection programmes and human medicine, yet for complex traits, no individual genetic variants associated with variance, as opposed to the mean, have been identified. Here we perform a meta-analysis of genome-wide association studies of phenotypic variation using similar to 170,000 samples on height and body mass index (BMI) in human populations. We report evidence that the single nucleotide polymorphism (SNP) rs7202116 at the FTO gene locus, which is known to be associated with obesity (as measured by mean BMI for each rs7202116 genotype)(5-7), is also associated with phenotypic variability. We show that the results are not due to scale effects or other artefacts, and find no other experiment-wise significant evidence for effects on variability, either at loci other than FTO for BMI or at any locus for height. The difference in variance for BMI among individuals with opposite homozygous genotypes at the FTO locus is approximately 7%, corresponding to a difference of similar to 0.5 kilograms in the standard deviation of weight. Our results indicate that genetic variants can be discovered that are associated with variability, and that between-person variability in obesity can partly be explained by the genotype at the FTO locus. The results are consistent with reported FTO by environment interactions for BMI8, possibly mediated by DNA methylation(9,10). Our BMI results for other SNPs and our height results for all SNPs suggest that most genetic variants, including those that influence mean height or mean BMI, are not associated with phenotypic variance, or that their effects on variability are too small to detect even with samples sizes greater than 100,000.
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| 13. |
- Smith, Anderson D., et al.
(författare)
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Biaxial strain in suspended graphene membranes for piezoresistive sensing
- 2014
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Ingår i: 2014 IEEE 27th International Conference on Micro Electro Mechanical Systems (MEMS). - : IEEE. - 9781479935093 ; , s. 1055-1058
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Konferensbidrag (refereegranskat)abstract
- Pressure sensors based on suspended graphene membranes have shown extraordinary sensitivity for uniaxial strains, which originates from graphene's unique electrical and mechanical properties and thinness [1]. This work compares through both theory and experiment the effect of cavity shape and size on the sensitivity of piezoresistive pressure sensors based on suspended graphene membranes. Further, the paper analyzes the effect of both biaxial and uniaxial strain on the membranes. Previous studies examined uniaxial strain through the fabrication of long, rectangular cavities. The present work uses circular cavities of varying sizes in order to obtain data from biaxially strained graphene membranes.
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| 14. |
- Smith, Anderson David, et al.
(författare)
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Graphene-based piezoresistive pressure sensing for uniaxial and biaxial strains
- 2014
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Ingår i: 2014 Silicon Nanoelectronics Workshop, SNW 2014. - : Institute of Electrical and Electronics Engineers (IEEE). - 9781479956777
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Konferensbidrag (refereegranskat)abstract
- The piezoresistive effect in graphene has been experimentally demonstrated for both uniaxial and biaxial strains. For uniaxial strain, rectangular membranes were measured while circular membranes provided biaxial strain. Gauge factors have also been extracted and compared to previous literature as well as simulations.
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| 15. |
- van der Harst, Pim, et al.
(författare)
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Seventy-five genetic loci influencing the human red blood cell
- 2012
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Ingår i: Nature. - : Springer Science and Business Media LLC. - 0028-0836 .- 1476-4687. ; 492:7429, s. 369-375
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Tidskriftsartikel (refereegranskat)abstract
- Anaemia is a chief determinant of global ill health, contributing to cognitive impairment, growth retardation and impaired physical capacity. To understand further the genetic factors influencing red blood cells, we carried out a genome-wide association study of haemoglobin concentration and related parameters in up to 135,367 individuals. Here we identify 75 independent genetic loci associated with one or more red blood cell phenotypes at P < 10(-8), which together explain 4-9% of the phenotypic variance per trait. Using expression quantitative trait loci and bioinformatic strategies, we identify 121 candidate genes enriched in functions relevant to red blood cell biology. The candidate genes are expressed preferentially in red blood cell precursors, and 43 have haematopoietic phenotypes in Mus musculus or Drosophila melanogaster. Through open-chromatin and coding-variant analyses we identify potential causal genetic variants at 41 loci. Our findings provide extensive new insights into genetic mechanisms and biological pathways controlling red blood cell formation and function.
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| 16. |
- Antelius, Mikael, et al.
(författare)
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Hermetic integration of liquids using high-speed stud bump bonding for cavity sealing at the wafer level
- 2012
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Ingår i: Journal of Micromechanics and Microengineering. - : IOP Publishing. - 0960-1317 .- 1361-6439. ; 22:4, s. 045021-
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Tidskriftsartikel (refereegranskat)abstract
- This paper reports a novel room-temperature hermetic liquid sealing process where the access ports of liquid-filled cavities are sealed with wire-bonded stud bumps. This process enables liquids to be integrated at the fabrication stage. Evaluation cavities were manufactured and used to investigate the mechanical and hermetic properties of the seals. Measurements on the successfully sealed structures show a helium leak rate of better than 10 (10) mbarL s (1), in addition to a zero liquid loss over two months during storage near boiling temperature. The bond strength of the plugs was similar to standard wire bonds on flat surfaces.
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| 17. |
- Antelius, Mikael, et al.
(författare)
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Wafer-Level Vacuum Sealing by Coining of Wire Bonded Gold Bumps
- 2013
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Ingår i: Journal of microelectromechanical systems. - 1057-7157 .- 1941-0158. ; 22:6, s. 1347-1353
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Tidskriftsartikel (refereegranskat)abstract
- This paper reports on the investigation of a novel room-temperature vacuum sealing method based on compressing wire bonded gold bumps which are placed to partially overlap the access ports into the cavity. The bump compression, which is done under vacuum, causes a material flow into the access ports, thereby hermetically sealing a vacuum inside the cavities. The sealed cavity pressure was measured by residual gas analysis to 8x10(-4) mbar two weeks after sealing. The residual gas content was found to be mainly argon, which indicates the source as outgassing inside the cavity and no measurable external leak. The seals are found to be mechanically robust and easily implemented by the use of standard commercial tools and processes.
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| 18. |
- Braun, Stefan, et al.
(författare)
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Method for the wafer-level integration of shape memory alloy wires
- 2013
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Patent (populärvet., debatt m.m.)abstract
- The present invention relates to a method to attach a shape memory alloy wire to a substrate, where the wire is mechanically attached into a 3D structure on the substrate. The present invention also relates to a device comprising a shape memory alloy wire attached to a substrate, where the wire is mechanically attached into a 3D structure on the substrate.
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| 19. |
- Dimas, Antigone S, et al.
(författare)
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Impact of type 2 diabetes susceptibility variants on quantitative glycemic traits reveals mechanistic heterogeneity.
- 2014
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Ingår i: Diabetes. - : American Diabetes Association. - 1939-327X .- 0012-1797. ; 63:6, s. 2158-2171
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Tidskriftsartikel (refereegranskat)abstract
- Patients with established type 2 diabetes display both beta-cell dysfunction and insulin resistance. To define fundamental processes leading to the diabetic state, we examined the relationship between type 2 diabetes risk variants at 37 established susceptibility loci and indices of proinsulin processing, insulin secretion and insulin sensitivity. We included data from up to 58,614 non-diabetic subjects with basal measures, and 17,327 with dynamic measures. We employed additive genetic models with adjustment for sex, age and BMI, followed by fixed-effects inverse variance meta-analyses. Cluster analyses grouped risk loci into five major categories based on their relationship to these continuous glycemic phenotypes. The first cluster (PPARG, KLF14, IRS1, GCKR) was characterized by primary effects on insulin sensitivity. The second (MTNR1B, GCK) featured risk alleles associated with reduced insulin secretion and fasting hyperglycemia. ARAP1 constituted a third cluster characterized by defects in insulin processing. A fourth cluster (including TCF7L2, SLC30A8, HHEX/IDE, CDKAL1, CDKN2A/2B) was defined by loci influencing insulin processing and secretion without detectable change in fasting glucose. The final group contained twenty risk loci with no clear-cut associations to continuous glycemic traits. By assembling extensive data on continuous glycemic traits, we have exposed the diverse mechanisms whereby type 2 diabetes risk variants impact disease predisposition.
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| 20. |
- Ericsson, Per, et al.
(författare)
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Toward 17µm pitch heterogeneously integrated Si/SiGe quantum well bolometer focal plane arrays
- 2011
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Ingår i: Infrared Technology and Applications XXXVII. - : SPIE - International Society for Optical Engineering. ; , s. 801216-1-801216-9
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Konferensbidrag (refereegranskat)abstract
- Most of today's commercial solutions for un-cooled IR imaging sensors are based on resistive bolometers using either Vanadium oxide (VOx) or amorphous Silicon (a-Si) as the thermistor material. Despite the long history for both concepts, market penetration outside high-end applications is still limited. By allowing actors in adjacent fields, such as those from the MEMS industry, to enter the market, this situation could change. This requires, however, that technologies fitting their tools and processes are developed. Heterogeneous integration of Si/SiGe quantum well bolometers on standard CMOS read out circuits is one approach that could easily be adopted by the MEMS industry. Due to its mono crystalline nature, the Si/SiGe thermistor material has excellent noise properties that result in a state-ofthe- art signal-to-noise ratio. The material is also stable at temperatures well above 450°C which offers great flexibility for both sensor integration and novel vacuum packaging concepts. We have previously reported on heterogeneous integration of Si/SiGe quantum well bolometers with pitches of 40μm x 40μm and 25μm x 25μm. The technology scales well to smaller pixel pitches and in this paper, we will report on our work on developing heterogeneous integration for Si/SiGe QW bolometers with a pixel pitch of 17μm x 17μm.
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| 21. |
- Fischer, Andreas C., 1982-, et al.
(författare)
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3D Free-Form Patterning of Silicon by Ion Implantation, Silicon Deposition, and Selective Silicon Etching
- 2012
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Ingår i: Advanced Functional Materials. - : Wiley-VCH Verlagsgesellschaft. - 1616-301X .- 1616-3028. ; 22:19, s. 4004-4008
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Tidskriftsartikel (refereegranskat)abstract
- A method for additive layer-by-layer fabrication of arbitrarily shaped 3D silicon micro- and nanostructures is reported. The fabrication is based on alternating steps of chemical vapor deposition of silicon and local implantation of gallium ions by focused ion beam (FIB) writing. In a final step, the defined 3D structures are formed by etching the silicon in potassium hydroxide (KOH), in which the local ion implantation provides the etching selectivity. The method is demonstrated by fabricating 3D structures made of two and three silicon layers, including suspended beams that are 40 nm thick, 500 nm wide, and 4 μm long, and patterned lines that are 33 nm wide.
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| 22. |
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| 23. |
- Fischer, Andreas C., et al.
(författare)
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3D printing of silicon micro and nano structures by ion implantation, silicon deposition, and selective silicon etching
- 2013
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Ingår i: Technical Paper - Society of Manufacturing Engineers.
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Konferensbidrag (refereegranskat)abstract
- A method for additive layer-by-layer fabrication of arbitrarily shaped 3D silicon micro and nano structures is reported. The fabrication is based on alternating steps of chemical vapor deposition of silicon and local implantation of gallium ions by focused ion beam (FIB) writing. In a final step, the defined 3D structures are formed by etching the silicon in potassium hydroxide (KOH), in which the local ion implantation provides the etching selectivity. The proposed technology could change and greatly simplify the fabrication of many MEMS, NEMS, and silicon photonic devices without requiring a fully equipped semiconductor cleanroom. This layer-by-layer fabrication method is in principle also viable for the implementation of 3D structures in semiconductors other than silicon.
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| 24. |
- Fischer, Andreas C., 1982-, et al.
(författare)
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A method and an apparatus for forming electrically conductive vias in a substrate, an automated robot-based manufacturing system, a component comprising a substrate with via holes, and an interposer device
- 2010
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Patent (populärvet., debatt m.m.)abstract
- A method for forming conductive vias in a substrate (302) by filling preformed via holes (303-305), preferably through via holes, with conductive material, comprises providing a plurality of preformed objects at least partly comprising ferromagnetic material (301) on a surface of the substrate; providing a magnetic source (307) on an opposite side of the substrate with respect to the plurality of preformed objects, thereby at least partly aligning at least a portion of the preformed objects with a magnetic field associated with the magnetic source; and moving the magnetic source relative the substrate, or vice versa, thereby moving the at least portion of the preformed objects into at least a portion of the via holes.
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| 25. |
- Fischer, Andreas C., et al.
(författare)
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Fabrication of high aspect ratio through silicon vias (TSVs) by magnetic assembly of nickel wires
- 2011
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Ingår i: Micro Electro Mechanical Systems (MEMS), 2011 IEEE 24th International Conference on. - : IEEE. - 9781424496327 ; , s. 37-40
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Konferensbidrag (refereegranskat)abstract
- Three-dimensional (3D) integration of electronics and/or MEMS-based transducers is an emerging technology that vertically interconnects stacked dies using through silicon vias (TSVs). They enable the realization of devices with shorter signal lengths, smaller packages and lower parasitic capacitances, which can result in higher performance and lower costs of the system. This paper presents a novel low-cost fabrication technique for solid metal-filled TSVs using nickel wires as conductive path. The wires are placed in the via hole of a silicon wafer by magnetic self-assembly. This metal filling technique enables through-wafer vias with high aspect ratios and potentially eliminates characteristic cost drivers of the TSV production such as metallization processes, wafer thinning and general issues associated with thin-wafer handling.
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| 26. |
- Fischer, Andreas C., 1982-, et al.
(författare)
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Free form printing of silicon micro- and nanostructures
- 2010
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Patent (populärvet., debatt m.m.)abstract
- The invention relates to a method of making a three-dimensional structure in semiconductor material. A substrate (20) is provided having at least a surface comprising semiconductor material. Selected areas of the surface of the substrate are to a focused ion beam whereby the ions are implanted in the semiconductor material in said selected areas. Several layers of a material selected from the group consisting of mono-crystalline, poly-crystalline or amorphous semiconductor material, are deposited on the substrate surface and between depositions focused ion beam is used to expose the surface so as to define a three-dimensional structure. Material not part of the final structure (30) defined by the focused ion beam is etched away so as to provide a three-dimensional structure on said substrate (20).
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| 27. |
- Fischer, Andreas C., 1982-, et al.
(författare)
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Heterogeneous Integration for Optical MEMS
- 2010
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Ingår i: 2010 23RD ANNUAL MEETING OF THE IEEE PHOTONICS SOCIETY. - NEW YORK : IEEE. - 9781424453696 ; , s. 487-488
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Konferensbidrag (refereegranskat)abstract
- In this paper we present different large-scale heterogeneous integration technologies for optical MEMS that enable the integration of optical MEMS with standard CMOS-based ICs. Examples that are presented include various monocrystalline silicon micro-mirror arrays and infrared bolometer arrays.
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| 28. |
- Fischer, Andreas C., 1982-, et al.
(författare)
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high aspect ratio tsvs fabricated by magnetic self-assembly of gold-coated nickel wires
- 2012
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Ingår i: Electronic Components and Technology Conference (ECTC), 2012 IEEE 62nd. - : IEEE conference proceedings. - 9781467319652 ; , s. 541-547
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Konferensbidrag (refereegranskat)abstract
- Three-dimensional (3D) integration is an emerging technologythat vertically interconnects stacked dies of electronics and/orMEMS-based transducers using through silicon vias (TSVs).TSVs enable the realization of devices with shorter signal lengths,smaller packages and lower parasitic capacitances, which can resultin higher performance and lower costs of the system. Inthis paper we demonstrate a new manufacturing technology forhigh-aspect ratio (> 8) through silicon metal vias using magneticself-assembly of gold-coated nickel rods inside etched throughsilicon-via holes. The presented TSV fabrication technique enablesthrough-wafer vias with high aspect ratios and superior electricalcharacteristics. This technique eliminates common issues inTSV fabrication using conventional approaches, such as the metaldeposition and via insulation and hence it has the potential to reducesignificantly the production costs of high-aspect ratio stateof-the-art TSVs for e.g. interposer, MEMS and RF applications.
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| 29. |
- Fischer, Andreas C., 1982-
(författare)
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Integration and Fabrication Techniques for 3D Micro- and Nanodevices
- 2012
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The development of micro and nano-electromechanical systems (MEMS and NEMS) with entirely new or improved functionalities is typically based on novel or improved designs, materials and fabrication methods. However, today’s micro- and nano-fabrication is restrained by manufacturing paradigms that have been established by the integrated circuit (IC) industry over the past few decades. The exclusive use of IC manufacturing technologies leads to limited material choices, limited design flexibility and consequently to sub-optimal MEMS and NEMS devices. The work presented in this thesis breaks new ground with a multitude of novel approaches for the integration of non-standard materials that enable the fabrication of 3D micro and nanoelectromechanical systems. The objective of this thesis is to highlight methods that make use of non-standard materials with superior characteristics or methods that use standard materials and fabrication techniques in a novel context. The overall goal is to propose suitable and cost-efficient fabrication and integration methods, which can easily be made available to the industry.The first part of the thesis deals with the integration of bulk wire materials. A novel approach for the integration of at least partly ferromagnetic bulk wire materials has been implemented for the fabrication of high aspect ratio through silicon vias. Standard wire bonding technology, a very mature back-end technology, has been adapted for yet another through silicon via fabrication method and applications including liquid and vacuum packaging as well as microactuators based on shape memory alloy wires. As this thesis reveals, wire bonding, as a versatile and highly efficient technology, can be utilized for applications far beyond traditional interconnections in electronics packaging.The second part presents two approaches for the 3D heterogeneous integration based on layer transfer. Highly efficient monocrystalline silicon/ germanium is integrated on wafer-level for the fabrication of uncooled thermal image sensors and monolayer-graphene is integrated on chip-level for the use in diaphragm-based pressure sensors.The last part introduces a novel additive fabrication method for layer-bylayer printing of 3D silicon micro- and nano-structures. This method combines existing technologies, including focused ion beam implantation and chemical vapor deposition of silicon, in order to establish a high-resolution fabrication process that is related to popular 3D printing techniques.
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| 30. |
- Fischer, Andreas C., et al.
(författare)
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Investigation of Thermal Storage Operation Strategies with Heat Pumps in German Multi Family Houses
- 2014
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Ingår i: Energy Procedia. - : Elsevier. - 1876-6102. ; , s. 137-144
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Konferensbidrag (refereegranskat)abstract
- The use of air source heat pumps is an efficient method to provide heat for space heating and domestic hot water in residential buildings, which cover roughly one third of the German domestic energy use. Capacity controlled heat pumps are gaining increased market share and provide high flexibility in operation. The possibility to use thermal storage to decouple thermal production and electric load from the heat pump can be used for operation strategies, hereby increasing the possibility to integrate electricity production from renewable energy sources. In the work presented, a range of operational strategies for capacity controlled heat pumps connected to a thermal storage in German multifamily houses are introduced and evaluated. The use cases include maximization of energy performance, cost minimization and utilization of on-site photovoltaic production. For optimal storage operation a model predictive control (MPC) approach using quadratic programming is presented together with simplified models of the multi-family house, a thermal storage and a capacity controlled air-to-water heat pump, the MPC creates a control signal to the heat pump. The resulting control signal is then applied to a detailed heat pump model to investigate the impact on the efficiency of the heat pump unit and thereby its electric energy consumption with different storage options.Results show that the MPC strategy is able to adapt to different objectives. One of the most important findings is that changing the objective towards a variable day-ahead-price-based operation leads to decreased heat pump efficiency but increases revenue. The sensitivity analysis towards storage size shows little influence in the range of sizes investigated.
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| 31. |
- Fischer, Andreas C., et al.
(författare)
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Layer-by-layer 3D printing of Si micro- and nanostructures by Si deposition, ion implantation and selective Si etching
- 2012
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Ingår i: 12th IEEE Conference on Nanotechnology (IEEE-NANO), 2012. - : IEEE conference proceedings. - 9781467321983 ; , s. 1-4
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Konferensbidrag (refereegranskat)abstract
- In this paper we report a method for layer-by-layer printing of three-dimensional (3D) silicon (Si) micro- and nanostructures. This fabrication method is based on a sequence of alternating steps of chemical vapor deposition of Si and local implantation of gallium (Ga+) ions by focused ion beam (FIB) writing. The defined 3D structures are formed in a final step by selectively wet etching the non-implanted Si in potassium hydroxide (KOH). We demonstrate the viability of the method by fabricating 2 and 3-layer 3D Si structures, including suspended beams and patterned lines with dimensions on the nm-scale.
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| 32. |
- Fischer, Andreas C., 1982-, et al.
(författare)
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Low-Cost Through Silicon Vias (Tsvs) With Wire-Bonded Metal Cores And Low Capacitive Substrate-Coupling
- 2010
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Ingår i: MEMS 2010. - : IEEE. - 9781424457649 ; , s. 480-483
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Konferensbidrag (refereegranskat)abstract
- The three-dimensional (3D) integration of electronics and/or MEMS-based transducers is an emerging technology that vertically interconnects stacked dies using through silicon vias (TSVs). They enable the realization of devices with shorter signal lengths, smaller packages and lower parasitic capacitances, which can result in higher performance and lower costs. This paper presents a novel low-cost fabrication technique for metal-filled TSVs using bonded gold-wires as conductive path. In this concept the wires are surrounded by polymer, which acts both as an electrical insulator causing low capacitive coupling towards the substrate and as a buffer for thermo-mechanical stress.
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| 33. |
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| 34. |
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| 35. |
- Fischer, Andreas C., 1982-, et al.
(författare)
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Selective electroless nickel plating on oxygen-plasma-activated gold seed-layers for the fabrication of low contact resistance vias and microstructures
- 2010
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Ingår i: MEMS 2010. - : IEEE. - 9781424457618 ; , s. 472-475
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Konferensbidrag (refereegranskat)abstract
- This paper presents a novel technique to selectively deposit nickel by electroless plating on gold seed layers using an oxygen-plasma-activation step. No prior wet surface pre- treatments or metal oxide etches are required. This enables the manufacturing of low-resistance vias for heterogeneous three-dimensional (3D) integration of MEMS but it is also a suitable technique for the fabrication of arbitrary shaped nickel-microstructures using chemically stable and cost-effective electroless nickel plating baths.
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| 36. |
- Fischer, Andreas C., 1982-, et al.
(författare)
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Unconventional applications of wire bonding create opportunities for microsystem integration
- 2013
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Ingår i: Journal of Micromechanics and Microengineering. - : IOP publishing. - 0960-1317 .- 1361-6439. ; 23:8, s. 083001-
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Forskningsöversikt (refereegranskat)abstract
- Automatic wire bonding is a highly mature, cost-efficient and broadly available back-endprocess, intended to create electrical interconnections in semiconductor chip packaging. Modern production wire-bonding tools can bond wires with speeds of up to 30 bonds per second with placement accuracies of better than 2 mu m, and the ability to form each wire individually into a desired shape. These features render wire bonding a versatile tool also for integrating wires in applications other than electrical interconnections. Wire bonding has been adapted and used to implement a variety of innovative microstructures. This paper reviews unconventional uses and applications of wire bonding that have been reported in the literature. The used wire-bonding techniques and materials are discussed, and the implemented applications are presented. They include the realization and integration of coils, transformers, inductors, antennas, electrodes, through silicon vias, plugs, liquid and vacuum seals, plastic fibers, shape memory alloy actuators, energy harvesters and sensors.
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| 37. |
- Fischer, Andreas C., 1982-, et al.
(författare)
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Very high aspect ratio through-silicon vias (TSVs) fabricated using automated magnetic assembly of nickel wires
- 2012
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Ingår i: Journal of Micromechanics and Microengineering. - : Institute of Physics (IOP). - 0960-1317 .- 1361-6439. ; 22:10, s. 105001-
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Tidskriftsartikel (refereegranskat)abstract
- Through-silicon via (TSV) technology enables 3D-integrated devices with higher performance and lower cost as compared to 2D-integrated systems. This is mainly due to smaller dimensions of the package and shorter internal signal lengths with lower capacitive, resistive and inductive parasitics. This paper presents a novel low-cost fabrication technique for metal-filled TSVs with very high aspect ratios (>20). Nickel wires are placed in via holes of a silicon wafer by an automated magnetic assembly process and are used as a conductive path of the TSV. This metal filling technique enables the reliable fabrication of through-wafer vias with very high aspect ratios and potentially eliminates characteristic cost drivers in the TSV production such as advanced metallization processes, wafer thinning and general issues associated with thin-wafer handling.
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| 38. |
- Fischer, Andreas C., 1982-, et al.
(författare)
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Wafer-level integration of NiTi shape memory alloy wires for the fabrication of microactuators using standard wire bonding technology
- 2011
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Ingår i: 24th International Conference on Micro Electro Mechanical Systems (MEMS), 2011 IEEE. - : IEEE. ; , s. 348-351
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Konferensbidrag (refereegranskat)abstract
- This paper reports on the first integration of SMA wires into silicon based MEMS structures using a standard wire bonder. This approach allows fast and efficient placement, alignment and mechanical attachment of NiTi-based SMA wires to silicon-based MEMS. The wires are mechanically anchored and clamped into deep-etched silicon structures on a wafer. The placement precision is high with an average deviation of 4 #x03BC;m and the mechanical clamping is strong, allowing successful actuation of the SMA wires.
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| 39. |
- Fischer, Andreas C., 1982-, et al.
(författare)
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Wire-bonded through-silicon vias with low capacitive substrate coupling
- 2011
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Ingår i: Journal of Micromechanics and Microengineering. - : IOP Science. - 0960-1317 .- 1361-6439. ; 21:8, s. 085035-
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Tidskriftsartikel (refereegranskat)abstract
- Three-dimensional integration of electronics and/or MEMS-based transducers is an emerging technology that vertically interconnects stacked dies with through-silicon vias (TSVs). They enable the realization of circuits with shorter signal path lengths, smaller packages and lower parasitic capacitances, which results in higher performance and lower costs. This paper presents a novel technique for fabricating TSVs from bonded gold wires. The wires are embedded in a polymer, which acts both as an electrical insulator, resulting in low capacitive coupling toward the substrate and as a buffer for thermo-mechanical stress.
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| 40. |
- Fischer, Andreas C., 1982-, et al.
(författare)
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Wire-bonder-assisted integration of non-bondable SMA wires into MEMS substrates
- 2012
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Ingår i: Journal of Micromechanics and Microengineering. - : Institute of Physics Publishing (IOPP). - 0960-1317 .- 1361-6439. ; 22:5, s. 055025-
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Tidskriftsartikel (refereegranskat)abstract
- This paper reports on a novel technique for the integration of NiTi shape memory alloy wires and other non-bondable wire materials into silicon-based microelectromechanical system structures using a standard wire-bonding tool. The efficient placement and alignment functions of the wire-bonding tool are used to mechanically attach the wire to deep-etched silicon anchoring and clamping structures. This approach enables a reliable and accurate integration of wire materials that cannot be wire bonded by traditional means.
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| 41. |
- Forsberg, Fredrik, et al.
(författare)
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Heterogeneous 3D integration of 17 μm pitch Si/SiGe quantum well bolometer arrays for infrared imaging systems
- 2013
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Ingår i: Journal of Micromechanics and Microengineering. - : IOP Publishing. - 0960-1317 .- 1361-6439. ; 23:4
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Tidskriftsartikel (refereegranskat)abstract
- This paper reports on the realization of 17 μm × 17 μm pitch bolometer arrays for uncooled infrared imagers. Microbolometer arrays have been available in primarily defense applications since the mid-1980s and are typically based on deposited thin films on top of CMOS wafers that are surface-machined into sensor pixels. This paper instead focuses on the heterogeneous integration of monocrystalline Si/SiGe quantum-well-based thermistor material in a CMOS-compliant process using adhesive wafer bonding. The high-quality monocrystalline thermistor material opens up for potentially lower noise compared to commercially available uncooled microbolometer arrays together with a competitive temperature coefficient of resistance (TCR). Characterized bolometers had a TCR of -2.9% K-1 in vacuum, measured thermal conductances around 5 × 10-8 W K-1 and thermal time constants between 4.9 and 8.5 ms, depending on the design. Complications in the fabrication of stress-free bolometer legs and low-noise contacts are discussed and analyzed.
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| 42. |
- Forsberg, Fredrik, et al.
(författare)
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High-Performance Infrared Micro-Bolometer Arrays Manufactured Using Very Large Scale Heterogeneous Integration
- 2011
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Ingår i: OMN2011. ; , s. 9-10
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Konferensbidrag (refereegranskat)abstract
- This paper reports on the implementation and characterization of arrays of uncooled infrared bolometers containing mono-crystalline Si/SiGe quantum well (QW) thermistors. The bolometer arrays are integrated on silicon fan-out wafers using very-large scale heterogeneous integration that is compatible with standard CMOS wafers. Infrared bolometer arrays with 320x240 pixels and pixel pitches of 25 mu m x 25 mu m and 17 mu m x 17 mu m have been implemented, respectively.
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| 43. |
- Forsberg, Fredrik, et al.
(författare)
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Very large scale heterogeneous integration (VLSHI) and wafer-level vacuum packaging for infrared bolometer focal plane arrays
- 2013
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Ingår i: Infrared physics & technology. - : Elsevier BV. - 1350-4495 .- 1879-0275. ; 60, s. 251-259
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Tidskriftsartikel (refereegranskat)abstract
- Imaging in the long wavelength infrared (LWIR) range from 8 to 14 μm is an extremely useful tool for non-contact measurement and imaging of temperature in many industrial, automotive and security applications. However, the cost of the infrared (IR) imaging components has to be significantly reduced to make IR imaging a viable technology for many cost-sensitive applications. This paper demonstrates new and improved fabrication and packaging technologies for next-generation IR imaging detectors based on uncooled IR bolometer focal plane arrays. The proposed technologies include very large scale heterogeneous integration for combining high-performance, SiGe quantum-well bolometers with electronic integrated read-out circuits and CMOS compatible wafer-level vacuum packing. The fabrication and characterization of bolometers with a pitch of 25 μm × 25 μm that are arranged on read-out-wafers in arrays with 320 × 240 pixels are presented. The bolometers contain a multi-layer quantum well SiGe thermistor with a temperature coefficient of resistance of -3.0%/K. The proposed CMOS compatible wafer-level vacuum packaging technology uses Cu-Sn solid-liquid interdiffusion (SLID) bonding. The presented technologies are suitable for implementation in cost-efficient fabless business models with the potential to bring about the cost reduction needed to enable low-cost IR imaging products for industrial, security and automotive applications.
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| 44. |
- Frick, Andreas, et al.
(författare)
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Classifying social anxiety disorder using multivoxel pattern analyses of brain function and structure
- 2014
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Ingår i: Behavioural Brain Research. - : Elsevier BV. - 0166-4328 .- 1872-7549. ; 75:9, s. 358S-358S
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Tidskriftsartikel (refereegranskat)abstract
- Functional neuroimaging of social anxiety disorder (SAD) support altered neural activation to threat-provoking stimuli focally in the fear network, while structural differences are distributed over the temporal and frontal cortices as well as limbic structures. Previous neuroimaging studies have investigated the brain at the voxel level using mass-univariate methods which do not enable detection of more complex patterns of activity and structural alterations that may separate SAD from healthy individuals. Support vector machine (SVM) is a supervised machine learning method that capitalizes on brain activation and structural patterns to classify individuals. The aim of this study was to investigate if it is possible to discriminate SAD patients (n = 14) from healthy controls (n = 12) using SVM based on (1) functional magnetic resonance imaging during fearful face processing and (2) regional gray matter volume. Whole brain and region of interest (fear network) SVM analyses were performed for both modalities. For functional scans, significant classifications were obtained both at whole brain level and when restricting the analysis to the fear network while gray matter SVM analyses correctly classified participants only when using the whole brain search volume. These results support that SAD is characterized by aberrant neural activation to affective stimuli in the fear network, while disorder-related alterations in regional gray matter volume are more diffusely distributed over the whole brain. SVM may thus be useful for identifying imaging biomarkers of SAD.
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| 45. |
- Gylfason, Kristinn B., 1978-, et al.
(författare)
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Process considerations for layer-by-layer 3D patterning of silicon, using ion implantation, silicon deposition, and selective silicon etching
- 2012
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Ingår i: Journal of Vacuum Science & Technology B. - : American Vacuum Society. - 1071-1023 .- 1520-8567. ; 30:6, s. 06FF05-
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Tidskriftsartikel (refereegranskat)abstract
- The authors study suitable process parameters, and the resulting pattern formation, in additive layer-by-layer fabrication of arbitrarily shaped three-dimensional (3D) silicon (Si) micro- and nanostructures. The layer-by-layer fabrication process investigated is based on alternating steps of chemical vapor deposition of Si and local implantation of gallium ions by focused ion beam writing. In a final step, the defined 3D structures are formed by etching the Si in potassium hydroxide, where the ion implantation provides the etching selectivity.
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| 46. |
- Reynolds, Simone L, et al.
(författare)
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Scabies mite inactive serine proteases are potent inhibitors of the human complement lectin pathway.
- 2014
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Ingår i: PLoS Neglected Tropical Diseases. - : Public Library of Science (PLoS). - 1935-2735. ; 8:5
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Tidskriftsartikel (refereegranskat)abstract
- Scabies is an infectious skin disease caused by the mite Sarcoptes scabiei and has been classified as one of the six most prevalent epidermal parasitic skin diseases infecting populations living in poverty by the World Health Organisation. The role of the complement system, a pivotal component of human innate immunity, as an important defence against invading pathogens has been well documented and many parasites have an arsenal of anti-complement defences. We previously reported on a family of scabies mite proteolytically inactive serine protease paralogues (SMIPP-Ss) thought to be implicated in host defence evasion. We have since shown that two family members, SMIPP-S D1 and I1 have the ability to bind the human complement components C1q, mannose binding lectin (MBL) and properdin and are capable of inhibiting all three human complement pathways. This investigation focused on inhibition of the lectin pathway of complement activation as it is likely to be the primary pathway affecting scabies mites. Activation of the lectin pathway relies on the activation of MBL, and as SMIPP-S D1 and I1 have previously been shown to bind MBL, the nature of this interaction was examined using binding and mutagenesis studies. SMIPP-S D1 bound MBL in complex with MBL-associated serine proteases (MASPs) and released the MASP-2 enzyme from the complex. SMIPP-S I1 was also able to bind MBL in complex with MASPs, but MASP-1 and MASP-2 remained in the complex. Despite these differences in mechanism, both molecules inhibited activation of complement components downstream of MBL. Mutagenesis studies revealed that both SMIPP-Ss used an alternative site of the molecule from the residual active site region to inhibit the lectin pathway. We propose that SMIPP-Ss are potent lectin pathway inhibitors and that this mechanism represents an important tool in the immune evasion repertoire of the parasitic mite and a potential target for therapeutics.
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| 47. |
- Schröder, Stephan, 1979-, et al.
(författare)
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Stress-minimized packaging of inertial sensors using wire bonding
- 2013
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Ingår i: 2013 Transducers and Eurosensors XXVII. - : IEEE conference proceedings. - 9781467359818 - 9781467359832 ; , s. 1962-1965
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Konferensbidrag (refereegranskat)abstract
- This paper presents a packaging approach for inertial sensors using wire bonding technology. The die is mounted exclusively by bond wires on the front- and backside to the package. Conventional single-side die attach to substrates, such as gluing, is abandoned. The approach is characterized by its novel and symmetric die attach concept as well as its simplicity of applying a standard wire bonding process. The wire bond attachment facilitates significant reduction of thermally induced mechanical stresses. The attachment concept is characterized in terms of attachment stiffness and potential die resonances using Laser Doppler Vibrometry (LDV). White-light interferometry is used to investigate stress related warping that is induced by the die attachment process.
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| 48. |
- Schröder, Stephan, 1979-, et al.
(författare)
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Very high aspect ratio through silicon vias (TSVs) using wire bonding
- 2013
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Ingår i: Transducers & Eurosensors XXVII. - : IEEE conference proceedings. - 9781467359832 ; , s. 167-170
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Konferensbidrag (refereegranskat)abstract
- This paper reports a fabrication approach for very high aspect ratio through silicon vias (TSVs). The metal filling of the through via holes is implemented by adapting standard wire bonding technology. TSVs with a diameter of 30 μm and aspect ratios between 10:1 and 20:1 have been fabricated. Basic electrical characterization and optical inspection have been conducted to verify the resistance and integrity of the metal and insulator filling of the TSV.
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| 49. |
- Smith, Anderson D., et al.
(författare)
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Pressure sensors based on suspended graphene membranes
- 2013
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Ingår i: Solid-State Electronics. - : Elsevier BV. - 0038-1101 .- 1879-2405. ; 88, s. 89-94
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Tidskriftsartikel (refereegranskat)abstract
- A novel pressure sensor based on a suspended graphene membrane is proposed. The sensing mechanism is explained based on tight binding calculations of strain-induced changes in the band structure. A CMOS compatible fabrication process is proposed and used to fabricate prototypes. Electrical measurement data demonstrates the feasibility of the approach, which has the advantage of not requiring a separate strain gauge, i.e. the strain gauge is integral part of the pressure sensor membrane. Hence, graphene membrane based pressure sensors can in principle be scaled quite aggressively in size.
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| 50. |
- Smith, Anderson, et al.
(författare)
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Electromechanical Piezoresistive Sensing in Suspended Graphene Membranes
- 2013
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Ingår i: Nano letters (Print). - : American Chemical Society (ACS). - 1530-6984 .- 1530-6992. ; 13:7, s. 3237-3242
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Tidskriftsartikel (refereegranskat)abstract
- Monolayer graphene exhibits exceptional electronic and mechanical properties, making it a very promising material for nanoelectromechanical devices. Here, we conclusively demonstrate the piezoresistive effect in graphene in a nanoelectromechanical membrane configuration that provides direct electrical readout of pressure to strain transduction. This makes it highly relevant for an important class of nanoelectromechanical system (NEMS) transducers. This demonstration is consistent with our simulations and previously reported gauge factors and simulation values. The membrane in our experiment acts as a strain gauge independent of crystallographic orientation and allows for aggressive size scalability. When compared with conventional pressure sensors, the sensors have orders of magnitude higher sensitivity per unit area.
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