| 1. |
- Achterberg, A., et al.
(författare)
-
The search for muon neutrinos from northern hemisphere gamma-ray bursts with AMANDA
- 2008
-
Ingår i: Astrophysical Journal. - : American Astronomical Society. - 0004-637X .- 1538-4357. ; 674:1, s. 357-370
-
Tidskriftsartikel (refereegranskat)abstract
- We present the results of the analysis of neutrino observations by the Antarctic Muon and Neutrino Detector Array (AMANDA) correlated with photon observations of more than 400 gamma-ray bursts (GRBs) in the northern hemisphere from 1997 to 2003. During this time period, AMANDA's effective collection area for muon neutrinos was larger than that of any other existing detector. After the application of various selection criteria to our data, we expect similar to 1 neutrino event and <2 background events. Based on our observations of zero events during and immediately prior to the GRBs in the data set, we set the most stringent upper limit on muon neutrino emission correlated with GRBs. Assuming a Waxman-Bahcall spectrum and incorporating all systematic uncertainties, our flux upper limit has a normalization at 1 PeV of E-2 Phi(nu) <= 6.3 x 10(-9) GeV cm(-2) s(-1) sr(-1), with 90% of the events expected within the energy range of similar to 10 TeV to similar to 3 PeV. The impact of this limit on several theoretical models of GRBs is discussed, as well as the future potential for detection of GRBs by next-generation neutrino telescopes. Finally, we briefly describe several modifications to this analysis in order to apply it to other types of transient point sources.
|
|
| 2. |
|
|
| 3. |
|
|
| 4. |
- Engstrom, O., et al.
(författare)
-
Navigation aids in the search for future high-k dielectrics : Physical and electrical trends
- 2007
-
Ingår i: Solid-State Electronics. - : Elsevier BV. - 0038-1101 .- 1879-2405. ; 51:4, s. 622-626
-
Tidskriftsartikel (refereegranskat)abstract
- From experimental literature data on metal oxides combined with theoretical estimates, we present empirical relations for k-values and energy band offset values, that can be used in the search for gate dielectric materials fulfilling the needs of future CMOS generations. Only a few materials investigated so far have properties meeting the demands for k and energy band offset values in the development of CMOS down to 22 nm. (c) 2007 Elsevier Ltd. All rights reserved.
|
|
| 5. |
- Engström, Olof, 1943, et al.
(författare)
-
A generalised methodology for oxide leakage current metric
- 2008
-
Ingår i: Proceeding of 9th European Workshop on Ultimate Integration of Silicon (ULIS), Udine, Italy. - 9781424417308 ; , s. 167-
-
Konferensbidrag (refereegranskat)abstract
- From calculations of semiconductor interfacecharge, oxide voltage and tunneling currents for MOSsystems with equivalent oxide thickness (EOT) in therange of 1 nm, rules are suggested for making itpossible to compare leakage quality of different oxideswith an accuracy of a factor 2 – 3 if the EOT is known.The standard procedure suggested gives considerablybetter accuracy than the commonly used method todetermine leakage at VFB+1V for n-type and VFB-1V forp-type substrates.
|
|
| 6. |
|
|
| 7. |
- Gottlob, H. D. B., et al.
(författare)
-
Gd silicate : A high-k dielectric compatible with high temperature annealing
- 2009
-
Ingår i: Journal of Vacuum Science & Technology B. - : American Vacuum Society. - 1071-1023 .- 1520-8567 .- 2166-2754 .- 2166-2746. ; 27:1, s. 249-252
-
Tidskriftsartikel (refereegranskat)abstract
- The authors report on the investigation of amorphous Gd-based silicates as high-k dielectrics. Two different stacks of amorphous gadolinium oxide (Gd(2)O(3)) and silicon oxide (SiO(2)) on silicon substrates are compared after annealing at temperatures up to 1000 degrees C. Subsequently formed metal oxide semiconductor capacitors show a significant reduction in the capacitance equivalent thicknesses after annealing. Transmission electron microscopy, medium energy ion scattering, and x-ray diffraction analysis reveal distinct structural changes such as consumption of the SiO(2) layer and formation of amorphous Gd silicate. The controlled formation of Gd silicates in this work indicates a route toward high-k dielectrics compatible with conventional, gate first complementary metal-oxide semiconductor integration schemes.
|
|
| 8. |
- Gottlob, H. D. B., et al.
(författare)
-
Gentle FUSI NiSi metal gate process for high-k dielectric screening
- 2008
-
Ingår i: Microelectronic Engineering. - : Elsevier BV. - 0167-9317 .- 1873-5568. ; 85:10, s. 2019-2021
-
Tidskriftsartikel (refereegranskat)abstract
- In this paper, a process flow well suited for screening of novel high-k dielectrics is presented. In vacuo silicon capping of the dielectrics excludes process and handling induced influences especially if hygroscopic materials are investigated. A gentle, low thermal budget process is demonstrated to form metal gate electrodes by turning the silicon capping into a fully silicided nickel silicide. This process enables the investigation of rare earth oxide based high-k dielectrics and specifically their intrinsic material properties using metal oxide semiconductor (MOS) capacitors. We demonstrate the formation of nickel monosilicide electrodes which show smooth interfaces to the lanthanum- and gadolinium-based high-k oxide films. The dielectrics have equivalent oxide thicknesses of EOT = 0.95 nm (lanthanum silicate) and EOT = 0.6 nm (epitaxial gadolinium oxide).
|
|
| 9. |
- Hurley, P. K., et al.
(författare)
-
Interface defects in HfO2, LaSiOx, and Gd2O3 high-k/metal-gate structures on silicon
- 2008
-
Ingår i: Journal of the Electrochemical Society. - : The Electrochemical Society. - 0013-4651 .- 1945-7111. ; 155:2, s. G13-G20
-
Tidskriftsartikel (refereegranskat)abstract
- In this work, we present experimental results examining the energy distribution of the relatively high (> 1 X 10(11) cm(-2)) electrically active interface defects which are commonly observed in high-dielectric-constant (high-k) metal-insulator-silicon systems during high-k process development. This paper extends previous studies on the Si(100)/SiOx/HfO2 system to include a comparative analysis of the density and energy distribution of interface defects for HfO2, lanthanum silicate (LaSiOx), and Gd2O3 thin films on (100) orientation silicon formed by a range of deposition techniques. The analysis of the interface defect density across the energy gap, for samples which experience no H-2/N-2 annealing following the gate stack formation, reveals a peak density (similar to 2 X 10(12) cm(-2) eV(-1) to similar to 1 X 10(13) cm(-2) eV(-1)) at 0.83-0.92 eV above the silicon valence bandedge for the HfO2, LaSiOx, and Gd2O3 thin films on Si (100). The characteristic peak in the interface state density (0.83-0.92 eV) is obtained for samples where no interface silicon oxide layer is observed from transmission electron microscopy. Analysis suggests silicon dangling bond (P-bo) centers as the common origin for the dominant interface defects for the various Si(100)/SiOx/high-k/metal gate systems. The results of forming gas (H-2/N-2) annealing over the temperature range 350-555 degrees C are presented and indicate interface state density reduction, as expected for silicon dangling bond centers. The technological relevance of the results is discussed. (c) 2007 The Electrochemical Society.
|
|
| 10. |
|
|
| 11. |
- Hurley, P.K., et al.
(författare)
-
Interface Defects in HfO2, LaSiOx, and Gd2O3 High-k/MetalGate Structures on Silicon
- 2008
-
Ingår i: J. Electrochem. Soc.. ; 155:2, s. G13-G20
-
Tidskriftsartikel (refereegranskat)abstract
- In this work, we present experimental results examining the energy distribution of the relatively high (>1×10^11 cm−2) electrically active interface defects which are commonly observed in high-dielectric-constant (high-k) metal–insulator–silicon systems during high-k process development. This paper extends previous studies on the Si(100)/SiOx/HfO2 system to include a comparative analysis of the density and energy distribution of interface defects for HfO2, lanthanum silicate (LaSiOx), and Gd2O3 thin films on (100) orientation silicon formed by a range of deposition techniques. The analysis of the interface defect density across the energy gap, for samples which experience no H2/N2 annealing following the gate stack formation, reveals a peak density (~2×10^12 cm−2 eV−1 to ~1×10^13 cm−2 eV−1) at 0.83–0.92 eV above the silicon valence bandedge for the HfO2, LaSiOx, and Gd2O3 thin films on Si(100). The characteristic peak in the interface state density (0.83–0.92 eV) is obtained for samples where no interface silicon oxide layer is observed from transmission electron microscopy. Analysis suggests silicon dangling bond (Pbo) centers as the common origin for the dominant interface defects for the various Si(100)/SiOx/high-k/metal gate systems. The results of forming gas (H2/N2) annealing over the temperature range 350–555°C are presented and indicate interface state density reduction, as expected for silicon dangling bond centers. The technological relevance of the results is discussed.
|
|
| 12. |
- Lu, Y., et al.
(författare)
-
Leakage current effects on C-V plots of high-k metal-oxide-semiconductor capacitors
- 2009
-
Ingår i: Journal of Vacuum Science & Technology B. - : American Vacuum Society. - 1071-1023 .- 1520-8567 .- 2166-2754 .- 2166-2746. ; 27:1, s. 352-355
-
Tidskriftsartikel (refereegranskat)abstract
- With the employment of ultrathin, high dielectric constant gate materials in advanced semiconductor technology, the conventional capacitance-voltage measurement technique exhibits a series of anomalies. In particular, a nonsaturating increase in the accumulation capacitance with reducing measurement frequency is frequently observed, which has not been adequately explained to our knowledge. In this article, the authors provide an explanation for this anomaly and hence set a criterion for the lower bound on measurement frequency. We then present a model which allows the easy extraction of the required parameters and apply it to an experimental set of data.
|
|
| 13. |
|
|
| 14. |
|
|
| 15. |
- Raeissi, Bahman, 1979, et al.
(författare)
-
High-k-oxide/silicon interfaces characterized by capacitance frequency spectroscopy
- 2007
-
Ingår i: ESSDERC 2007. - 9781424411238 ; , s. 283-286
-
Konferensbidrag (refereegranskat)abstract
- Electron capture into insulator/silicon interface states is investigated for high-k dielectrics of Gd(2)O(3) prepared by MBE and ALD, and for HfO(2) prepared by reactive sputtering, by measuring the frequency dependence of MOS capacitance. The capture cross sections are found to be thermally activated and to increase steeply with the energy depth of the interface electron states. The methodology adopted is considered useful for increasing the understanding of high-k-oxide/silicon interfaces.
|
|
| 16. |
- Raeissi, Bahman, 1979, et al.
(författare)
-
High-k-oxide/silicon interfaces characterized by capacitance frequency spectroscopy
- 2008
-
Ingår i: Solid-State Electronics. - : Elsevier BV. - 0038-1101 .- 1879-2405. ; 52:9, s. 1274-1279
-
Tidskriftsartikel (refereegranskat)abstract
- Electron capture into insulator/silicon interface states is investigated for high-k dielectrics of Gd2O3 preparedby molecular beam epitaxy (MBE) and atomic layer deposition (ALD), and for HfO2 prepared byreactive sputtering, by measuring the frequency dependence of Metal Oxide Semiconductor (MOS) capacitance.The capture cross sections are found to be thermally activated and to increase steeply with theenergy depth of the interface electron states. The methodology adopted is considered useful for increasingthe understanding of high-k-oxide/silicon interfaces.
|
|
| 17. |
- Strand, V, et al.
(författare)
-
An integrated analysis of five double-blind, randomized controlled trials evaluating the safety and efficacy of a hyaluronan product for intra-articular injection in osteoarthritis of the kneel
- 2006
-
Ingår i: Osteoarthritis and Cartilage. - : Elsevier BV. - 1063-4584. ; 14:9, s. 859-866
-
Tidskriftsartikel (refereegranskat)abstract
- Objective: Five double-blind, randomized, saline-controlled trials (RCTs) were included in the United States marketing application for an intra-articular hyaluronan (IA-HA) product for the treatment of osteoarthritis (OA) of the knee. We report an integrated analysis of the primary Case Report Form (CRF) data from these trials. Method. Trials were similar in design, patient population and outcome measures - all included the Lequesne Algofunctional Index (LI), a validated composite index of pain and function, evaluating treatment over 3 months. Individual patient data were pooled; a repeated measures analysis of covariance was performed in the intent-to-treat (ITT) population. Analyses utilized both fixed and random effects models. Safety data from the five RCTs were summarized. Results: A total of 1155 patients with radiologically confirmed knee OA were enrolled: 619 received three or five IA-HA injections; 536 received. "placebo" saline injections. In the active and control groups, mean ages were 61.8 and 61.4 years; 62.4% and 58.8% were women; baseline total Lequesne scores 11.03 and 11.30, respectively. Integrated analysis of the pooled data set found a statistically significant reduction (P < 0.001) in total Lequesne score with hyaluronan (HA) (-2.68) vs placebo (-2.00); estimated difference -0.68 (95% CI: -0.56 to -0.79), effect size 0.20. Additional modeling approaches confirmed robustness of the analyses. Conclusions: This integrated analysis demonstrates that multiple design factors influence the results of RCTs assessing efficacy of intra-articular (IA) therapies, and that integrated analyses based on primary data differ from meta-analyses using transformed data. (C) 2006 OsteoArthritis Research Society International. Published by Elsevier Ltd. All rights reserved.
|
|
