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1.	Araujo, C. M., et al. (author) Electrical resistivity, MNM transition and band-gap narrowing of cubic GaN : Si 2002 In: Microelectronics Journal. - 0026-2692. ; 33:4, s. 365-369 Journal article (peer-reviewed)abstract The electrical resistivity of the Si-donor cubic GaN is investigated theoretically at low temperature. The critical impurity concentration, N-c, for the metal-nonmetal transition is estimated in three different ways: from using the generalized Drude approach (GDA) for the resistivity; from the vanishing of the chemical potential calculated using the dielectric function model with a Lorentz-Lorenz correction; from finding the crossing point between the energy in the insulating and metallic states. The bandgap narrowing (BGN) has been determined theoretically and experimentally above the MNM transition, The experimental data have been obtained with photoluminescence measurements. Theoretical and experimental results are in rough agreement in the range of impurity concentration of interest.
2.	Iwata, H., et al. (author) A new type of quantum wells : Stacking faults in silicon carbide 2003 In: Microelectronics Journal. - 0026-2692. ; 34:5, s. 371-374 Conference paper (other academic/artistic)abstract We report on a new type of quantum wells with the width as thin as 10Å, which are composed of SiC only, and consequently have ideal interfaces. These quantum wells are actually stacking faults in SiC. Certain types of stacking faults in SiC polytypes create small 3C-like regions, where the stacking sequences along the c-axis become locally cubic in the hexagonal host crystals. Since the conduction band offsets between the cubic and hexagonal polytypes are very large with the conduction band minima of 3C-SiC lower than that of the other polytypes, such thin 3C inclusions can introduce locally lower conduction bands, thus acting as quantum films perpendicular to the c-axis. One mechanism for the occurrence of stacking faults in the perfect SiC single crystals is the motion of partial dislocations in the basal planes, the partial dislocations leaving behind stacking fault regions. © 2003 Elsevier Science Ltd. All rights reserved.
3.	Andersson, Henrik, et al. (author) System of nano-silver inkjet printed memory cards and PC card reader and programmer 2011 In: Microelectronics Journal. - : Elsevier BV. - 0959-8324 .- 0026-2692. ; 42:1, s. 21-27 Journal article (peer-reviewed)abstract This work describes the development of inkjet printed, low-cost memory cards, and complementary pair of memory card reader and card reader/programmer for PCs. This constitutes a complete system that can be used for various applications. The memory cards are manufactured by inkjet printing nano-silver ink on photo paper substrate. The printed memory structures have an initial high resistance that can later be programmed to specific values representing data on the cards, the so called Write Once Read Many (WORM) memories. The memory card reader measures the resistance values of the memory cells and reads it back to the computer by USB connection. Using multiple resistance levels that represent different states it is possible to have a larger number of selectable combinations with fewer physical bits compared to binary coding. This somewhat counters one of the limitations of resistive memory technology that basically each cell needs one physical contact. The number of possible states is related to the resolution of the reader and the stability of the WORM memory.
4.	Andersson, Thorvald, 1946, et al. (author) Macroscopic defects in GaN/AlN multiple quantum well structures grown by MBE on GaN templates 2009 In: Microelectronics Journal. - : Elsevier BV. - 0026-2692. ; 40:2, s. 360-362 Journal article (peer-reviewed)abstract We have used MBE to grow in AlN/GaN superlattices, with different number of periods, on 2.5-mu m-thick MOVPE-GaN templates to study the development of defects such as surface deformation due to strain. After growth the samples were studied by atomic force microscopy (AFM), transmission electron microscopy (TEM), XRD and Fourier transform infrared spectroscopy (FT-IR). The strain increased with the number of quantum wells (QWs) and eventually caused defects such as microcracks visible by optical microscopy at four or more QW periods. High-resolution TEM images showed shallow recessions on the surface (surface deformation) indicating formation of microcracks in the MQW region. The measured intersubband (IS) absorption linewidth from a four period structure was 97 meV, which is comparable with the spectrum from a 10 period structure at an absorption energy of similar to 700 meV. This indicates that the interface quality of the MQW is not substantially affected by the presence of cracks.
5.	Baroni, Mpma, et al. (author) Modeling and gradient pattern analysis of irregular SFM structures of porous silicon 2006 In: Microelectronics Journal. - : Elsevier BV. - 0026-2692. ; 37:4, s. 290-294 Journal article (peer-reviewed)abstract Technological applications in opto-electronic devices have increased the interest in characterizing porous silicon structure patterns. Due to its physical properties, solutions from KPZ 2D are adopted to simulate the structure of porous material interface whose spatial characteristics are equivalent to those found in porous silicon samples. The analysis of the simulated and real scanning Force Microscopy (SFM) surfaces was done using the Gradient Pattern Analysis (GPA). We found that the KPZ 2D model presented asymmetry levels compatible with the irregular surfaces observed by means of SFM images of pi-Si.
6.	Chouhan, Shailesh, et al. (author) A 352nW, 30 ppm/°C all MOS nano ampere current reference circuit 2017 In: Microelectronics Journal. - : Elsevier. - 0959-8324 .- 0026-2692. ; 69, s. 45-52 Journal article (peer-reviewed)abstract In this work, an ultra low power all-MOSFET based current reference circuit, developed in 0.18 µm CMOS technology, is presented. The proposed circuit is based on the classical resistor-less beta multiplier circuit with an additional temperature compensation feature. The circuit is capable of providing the reference current in a nanoampere range for the supply voltage ranging from 1 V to 2 V in the industrial temperature range of −40 °C to 85 °C. The measurements were performed on 10 prototypes. The measured mean value of the reference current is 58.7 nA with a mean temperature coefficient value of 30 ppm/°C. In addition, the measured mean line regulation is 3.4%/V in the given supply voltage range. The total current consumption of the circuit is 352 nA and the chip area is 0.036 mm2.
7.	Holtz, Per-Olof, 1951-, et al. (author) Effects of External Fields on the Excitonic Emission from Single InAs/GaAs Quantum Dots 2008 In: Microelectronics Journal, Vol. 39. - Microelectronics Journal : Elsevier. ; , s. 331-334 Conference paper (peer-reviewed)abstract A low-temperature micro-photoluminescence (μ-PL) investigation of InAs/GaAs quantum dots (QDs) exposed to a lateral external electric field is reported. It is demonstrated that the QDs PL signal could be increased several times by altering the external and/or the internal electric field. The internal field in the vicinity of the dots could be altered by means of an additional infra-red laser. We propose a model, which is based on an essentially faster lateral transport of the charge carriers achieved in an external electric field. Consequently, also the capture probability into the dots and subsequently the dot luminescence is also enhanced. The results obtained suggest that the lateral electric fields play a major role for the dot luminescence intensity measured in our experiment.
8.	Iwata, H, et al. (author) A new type of quantum wells : Stacking faults in SiC 2003 In: Microelectronics Journal. - 0026-2692. ; 34:5-8, s. 371-374 Journal article (peer-reviewed)
9.	Jalili, Armin, et al. (author) Inter-channel offset and gain mismatch correction for time-interleaved pipelined ADCs 2011 In: Microelectronics Journal. - Oxford, UK : Elsevier. - 0959-8324 .- 0026-2692. ; 42:1, s. 158-164 Journal article (peer-reviewed)abstract This paper presents a digital background calibration technique to compensate inter-channel gain and offset errors in parallel, pipelined analog-to-digital converters (ADCs). By using an extra analog path, calibration of each ADC channel is done without imposing any changes on the digitizing structure, i.e., keeping each channel completely intact. The extra analog path is simplified using averaging and chopping concepts, and it is realized in a standard 0.18‐μm CMOS technology. The complexity of the analog part of the proposed calibration system is same for a different number of channels.Simulation results of a behavioral 12-bit, dual channel, pipelined ADC show that offset and gain error tones are improved from −56.5 and −58.3 dB before calibration to about −86.7 and −103 dB after calibration, respectively.
10.	Johannesson, Daniel, et al. (author) Analytical PSpice model for SiC MOSFET based high power modules 2016 In: Microelectronics Journal. - : Elsevier. - 0026-2692. ; 53, s. 167-176 Journal article (peer-reviewed)abstract A simple analytical PSpice model has been developed and verified for a 4H–SiC based MOSFET power module with voltage and current ratings of 1200 V and 120 A. The analytical simulation model is a temperature dependent silicon carbide (SiC) MOSFET model that covers static and dynamic behavior, leakage current and breakdown voltage characteristics. The technology dependent MOSFET modeling parameters are extracted from characterization measurements, datasheets and PSpice simulations at various temperatures. The SiC MOSFET model is implemented in the PSpice circuit simulation platform using PSpice standard components and analog behavior modeling (ABM) blocks. The MOSFET switching performance is investigated under influence of different circuit elements, such as stray inductance, gate resistance and temperature, in order to study and estimate on-state and switching losses pre-requisite for design of various converter and inverter topologies. The performance of the SiC MOSFET model is fairly accurate and correlates well with the measured results over a wide temperature range.
11.	Karpyna, V A, et al. (author) Electron field emission from ZnO self-organized nanostructures and doped ZnO : Ga nanostructured films 2009 In: Microelectronics Journal. - : Elsevier BV. - 0959-8324 .- 0026-2692. ; 40:2, s. 229-231 Journal article (peer-reviewed)abstract Self-organized ZnO nanostructures were grown by thermal decomposition of metalorganic precursors as well as by carbothermal reduction process. Nanostructured undoped and gallium-doped ZnO nanostructured films were deposited by plasma-enhanced chemical vapor deposition from metalorganic compounds. Electron field emission follows Fowler-Nordheim equation. Efficient electron emission was obtained from self-organized nanorstructures due to their geometric shape. Enhanced field emission from ZnO:Ga nanorstructured films in comparison with undoped ZnO films is obliged to lowering work function at doping by gallium.
12.	Khan, Sajid, et al. (author) An ultra-low power, reconfigurable, aging resilient RO PUF for IoT applications 2019 In: Microelectronics Journal. - : Elsevier. - 0959-8324 .- 0026-2692. ; 92 Journal article (peer-reviewed)abstract Physically Unclonable Functions (PUF) have emerged as security primitives which can generate high entropy, temper resilient bits for security applications. However, the power budget of the ring oscillator (RO) PUF limits the use of RO PUF in IoT applications, in this concern a low power variant of RO PUF is much needed. In this paper, we have presented an ultra-low power, lightweight, configurable RO PUF based on the 4T XOR architecture. The proposed architecture is aging resilient; hence it produces a stable PUF output over the years. Also, it has a large number of challenge-response-pair (CRP) compared to the other architectures, which makes it suitable for chip identification as well as cryptographic key generation. The proposed PUF is implemented on 40 nm CMOS technology, and for the validation of design, we have also implemented on FPGA. The simulation results show that it has a uniqueness of 0.489 and worst-case reliability of 96.43% and 93.15% at 125 °C and 1.2 V, respectively. Compared to the conventional RO PUF it consumes 98.06% and 95.47% less dynamic and leakage power, respectively.
13.	Klason, P, et al. (author) Fabrication and characterization of p-Si/n-ZnO heterostructured junctions 2009 In: MICROELECTRONICS JOURNAL. - : Elsevier BV. - 0026-2692. ; 40:4-5, s. 706-710 Journal article (peer-reviewed)abstract In this paper ZnO nanorods and nanodots (with and without a SiO2 buffer layer) were grown on p-Si, forming p-n heterojunctions. The nanorod devices showed no visible electroluminescence (EL) emission but showed rectifying behavior. Covering around 60% of the length of the nanorods with PMMA produced an ideality factor of 3.91 +/- 0.11 together with a reverse saturation current of 6.53 +/- 4.2 x 10(-8) A. Up to two orders of magnitude rectification was observed for the current at bias -3 and 3 V. The nanodot devices showed EL emission under forward bias conditions. It seems that the buffer layer increased both the stability and efficiency of the devices, since the buffer layer device could operate at larger applied voltage and showed EL emission under reverse bias.
14.	Li, Jian-De, et al. (author) Co-placement optimization in sensor-reusable cyber-physical digital microfluidic biochips 2019 In: Microelectronics Journal. - : Elsevier. - 0959-8324 .- 0026-2692. ; 83, s. 185-196 Journal article (peer-reviewed)abstract Digital microfluidic biochips (DMFBs) facilitate modern healthcare applications. One of the most important applications is point-of-care (POC) clinical diagnosis which is directly related to human health. However, biochemical experiments are usually error-prone, which makes monitoring intermediate results during bioassay execution be required to ensure the correctness of POC clinical diagnosis. To tackle this problem, cyber-physical digital microfluidic biochips with integrated sensors have been proposed and have attracted attention recently. In order to fully utilize the sensors for detection, the reusability of sensors should be taken into consideration during the module placement stage of cyber-physical DMFBs synthesis flow. Moreover, excessive actuation of electrodes may cause reliability degradation and this issuse should also be taken care of during module placement stage. In order to deal with the aforementioned problems, this paper presents the first co-optimization method for both module and sensor placement. Experimental results show that the proposed method can effectively minimize bioassay completion time while meeting all constraints from sensors and electrodes.
15.	Norström, H., et al. (author) Formation of a buried collector layer in RF-bipolar devices by ion implantation 2006 In: MICROELECTRONICS JOURNAL. - : Elsevier BV. - 0026-2692. ; 37:11, s. 1366-1371 Journal article (peer-reviewed)abstract High-dose implantation of arsenic (As) buried collector layer formation for bipolar/BiCMOS processes has been studied. Wafers with and without screen oxide were subjected to high-dose implants with different energies. Some wafers were given a low-temperature anneal before XTEM and SIMS analyses. Defects observed after As implants of 6E15 cm(-2) through screen oxide after low-temperature anneal were annihilated at the subsequent high-temperature steps, but the direct implant of As into the silicon is preferred since fewer defects are generated and there is no knock-on of oxygen into the material. Fabricated devices showed excellent electrical performance. However, the upper limit (dose and/or energy) at which perfect recrystallization does no longer occur has not been defined and the process limit is consequently not established.
16.	Peibst, R., et al. (author) PECVD grown Ge nanocrystals embedded in SiO(2) : From disordered to templated self-organization 2009 In: MICROELECTRONICS JOURNAL. - : Elsevier BV. - 0026-2692. ; 40:4-5, s. 759-761 Journal article (peer-reviewed)abstract We present a new "templated self-organization" method for the preparation of Ge nanocrystals in SiO(2) that combines a bottom-up with a top-down approach for nanostructuring. Ge nanocrystals are formed by self-organization induced by thermal annealing of thin Ge films embedded ill SiO(2) whose areas are predefined by nanoimprint patterning. Thus Much smaller Structure sizes call be achieved than by pure nanostructuring and touch more regular structures call be prepared than by pure self-organization. in particular, the method enables the generation of Ge nanocrystals of equal size at predefined vertical and lateral positions thus facilitating the fabrication of nanoscaled devices due to the Suppression of Structural fluctuations.
17.	Persson, Clas, et al. (author) X-ray absorption and emission spectroscopy of ZnO nanoparticle and highly oriented ZnO microrod arrays 2006 In: Microelectronics Journal. - : Elsevier BV. - 0026-2692. ; 37:8, s. 686-689 Journal article (peer-reviewed)abstract The electronic structures of ZnO nanoparticles and microrod arrays are studied by 0 Is X-ray absorption spectroscopy (XAS) and O K alpha X-ray emission spectroscopy (XES). We show that the present LDA +U-SIC calculation approach is suitable to correct the LDA self-interaction error of the cation d-states. The atomic eigenstates of 3d in zinc and 2p in oxygen are energetically close, which induces strong Zn-3d-O-2p hybridization. This anomalous valence band cation-d-anion-p hybridization is affected when the localization of the Zn 3d-states is taken into account. Experimentally, the XES spectra show energy dependence in the spectral shape revealing selected excitations to the Zn 3d, 4s and 4p states, hybridized with 0 2p states. Strong anisotropic effects are observed for the highly oriented ZnO rods, but not for the isotropic spherical nanoparticles. The nanostructured ZnO has primarily bulk XAS and XES properties.
18.	Pettersson, Håkan, et al. (author) Photocurrent spectroscopy on self-assembled InAs quantum dots embedded in InP 2005 In: Microelectronics Journal. - Amsterdam : Elsevier. - 0026-2692. ; 36:3-6, s. 227-230 Journal article (peer-reviewed)abstract In this work, we report on an overview of recent results from Fourier transform photocurrent (FTPC) measurements in the infrared spectral region on ensembles of self-assembled InAs quantum dots embedded in a matrix of InP. In interband PC, clear signals related to the dots are observed. Comparing the PC- and PL spectra, we observe that the fundamental transition is absent in the PC spectra, which we interpret in terms of Pauliblocking due to a filled electron ground state of the dots. Our results furthermore suggest that an Auger process is involved in forming the interband PC signal. In intersubband PC, peaks related to transitions from the dots' ground- and first excited states to the conduction band of the matrix are observed. Using a novel approach of combining FTPC with illumination from an additional external non-modulated light source, we have measured the spectral distribution of photoionization of excitons in quantum dots and found an exciton binding energy in good agreement with theoretical calculations.
19.	Shen, Meigen, et al. (author) Robustness enhancement through chip-package co-design for high-speed electronics 2005 In: Microelectronics Journal. - : Elsevier BV. - 0959-8324 .- 0026-2692. ; 36:9, s. 846-855 Journal article (peer-reviewed)abstract The low interaction between chip and package design has an increasingly limiting effect on the system performance. In this paper, the chip-package co-design flow is presented. We address robustness enhancement under the package and interconnection constraints as well as process, voltage, and temperature (PVT) variations by using impedance control, optimal pins assignment and transmitter equalization. From the simulation results we find that without on-chip digital compensation circuit, the variation of the driver's output impedance is 37% under different PVT conditions. However, it is only 5% when digital compensation circuit is used. Through optimal pins assignment the effective inductance of the pins is reduced. When power and ground pins are used as shielding pins, crosstalk is also decreased by 10 dB. Transmitter equalization effectively decreases inter-symbol interference caused by interconnection attenuation and dispersion. In our design example we find that without equalization the eye-diagram is almost closed at the receiver end. On the other hand with one-tap pre-emphasis equalization the eye-diagram is open and has a height of 90 mV and a width of 140 ps. It is also found that there is a clear optimal window for high data rate in this design. Without a chip-package co-design such an optimal window will not be found.
20.	Tafuri, F., et al. (author) Coherent quasiparticle transport in grain boundary junctions employing high-T-c superconductors 2006 In: Microelectronics. - : Elsevier BV. - 0026-2692. ; 39:8, s. 1066-1069 Conference paper (peer-reviewed)abstract Magneto-fluctuations of the normal resistance R-N have been reproducibly observed in YBa2Cu3O7-delta biepitaxial grain boundary junctions at low temperatures. We attribute them to mesoscopic transport in narrow channels across the grain boundary line, occurring even in the presence of large voltage drops. The Thouless energy appears to be the relevant energy scale. Possible implications on the understanding of coherent transport of quasiparticles in high critical temperature superconductors (HTS) and of the dissipation mechanisms are discussed. (c) 2007 Elsevier Ltd. All rights reserved.
21.	Tomas, S. A., et al. (author) Optical and electronic characterization of the band structure of blue methylene and rhodamine 6G-doped TiO2 sol-gel nanofilms 2005 In: Microelectronics Journal. - : Elsevier BV. - 0026-2692. ; 36:3-6, s. 570-573 Journal article (peer-reviewed)abstract The optical properties and the band structure of TiO2 sol-gel thin films prepared by the sot-gel process and doped with methylene blue or rhodamine were studied by absorption, excitation and emission spectroscopy. The absorption spectra show two absorption bands, around 2.3 eV and above 3.0 eV suggesting that besides the excitation bands observed in rhodamine at 2.3 eV an efficient energy transfer occurs between the TiO2 conduction band and the molecular rhodamine excited states, yielding a strong emission band at 600 nm, while for methylene blue a strong hypsochromic shift of the absorption bands is observed. The optical absorption and band gap energy for the phase rutile of TiO2 films were calculated with a LDA+U/FPLAPW method, and a comparison of this calculation with experimental data of TiO2 films prepared by undoped sol-gel and sputtering is performed.
22.	Wang, S M, et al. (author) Dilute nitrides and 1.3 mu m GaInNAs quantum well lasers on GaAs 2009 In: MICROELECTRONICS JOURNAL. - : Elsevier BV. - 0026-2692. ; 40:3, s. 386-391 Journal article (peer-reviewed)abstract We present epitaxial growth of GaInNAs on GaAs by molecular beam epitaxy (MBE) using analog, digital and N irradiation methods. It is possible to realize GaInNAs quantum wells (QWs) with a maximum substitutional N concentration up to 6% and a strong light emission up to 1.71 mu m at 300 K. High quality 1.3 mu m GaInNAs multiple QW edge emitting laser diodes have been demonstrated. The threshold current density (for a cavity of 100 x 1000 mu m(2)) is 300, 300, 400 and 940 A/cm(2) for single, double, triple and quadruple QW lasers, respectively. The maximum 3 dB bandwidth reaches 17 GHz and high-speed transmission at 10 Gb/s up to 110 degrees C under a constant voltage has been demonstrated.
23.	Willander, Magnus, 1948, et al. (author) Solid and soft nanostructured materials: fundamentals and applications 2005 In: Microelectronics Journal. - : Elsevier BV. - 0026-2692. ; 36:11, s. 940-949 Journal article (peer-reviewed)abstract The scientific work worldwide on nanostructured materials is extensive as well as the work on the applications of nanostructured materials. We will review quasi two-, one- and zero-dimensional solid and soft materials and their applications. We will restrict ourselves to a few examples from partly fundamental aspects and partly from application aspects. We will start with trapping of excitons in semiconductor nanostructures. The subjects are: physical realizations, phase diagrams, traps, local density approximations, and mesoscopic condensates. From these fundamental questions in solid nanomaterials we will move to trapping of molecules in water using nanostructured electrodes. We will also discuss how to manipulate water (create vortices) by nanostructure materials. The second part deals with nanorods (nano-wires). Particularly we will exemplify with ZnO nanorods. The reason for this is that ZnO has: a very strong excitons binding energy (60 meV) and strong photon–excitons coupling energy, a strong tendency to create nanostructures, and properties which make the material of interest for both optoelectronics and for medical applications. We start with the growth of crystalline ZnO nanorods on different substrates, both crystalline (silicon, silicon carbide, sapphire, etc) and amorphous substrates (silicon dioxide, plastic materials, etc) for temperatures from 50 °C up to 900 °C. The optical properties and crystalline properties of the nanorods will be analyzed. Applications from optoelectronics (lasers, LEDs, lamps, and detectors) are analyzed and also medical applications like photodynamic cancer therapy are taken up. The third part deals with nano-particles in ZnO for sun screening. Skin cancer due to the exposure from the sun can be prevented by ZnO particles in a paste put on the exposed skin.

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