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41.
Electrical characterization analyses are proposed in this work using the Lambert function on Schottky junctions in GaN wide band gap semiconductor devices for extraction of physical parameters. The Lambert function is used to give an explicit expression of the current in the Schottky junction. This function is applied with defined conduction phenomena, whereas other work presented arbitrary (or undefined) conduction mechanisms in such parameters'' extractions. Based upon AlGaN/GaN HEMT structures, extractions of parameters are undergone in order to provide physical characteristics. This work highlights a new expression of current with defined conduction phenomena in order to quantify the physical properties of Schottky contacts in AlGaN/GaN HEMT transistors. 相似文献
42.
T. Alzanki R. Gwilliam N. G. Emerson B. J. Sealy 《Journal of Electronic Materials》2004,33(7):767-769
It is shown for the first time that antimony-implanted silicon produces the highest electrical activation (90%) with low resistivity
(<200 ohms/square) following low-temperature processing. Thus, annealing at 650°C produces the best results for antimony,
whereas for arsenic, it is necessary to anneal at temperatures above 1000°C to get optimum results. Silicon was implanted
with antimony at 12 keV and 40 keV and doses of 8.5×1014 cm−2 and 4×1014 cm−2, respectively, and arsenic at equivalent energies and doses. The electrical data from both implants are compared in order
to identify the process conditions require to obtain optimum results. It is demonstrated that annealing below 800°C produces
electrical profiles with no measurable diffusion of the antimony, but higher temperature anneals produce significant diffusional
broadening. 相似文献
43.
44.
Toward multiple maximum power point estimation of photovoltaic systems based on semiconductor theory
Jen‐Cheng Wang Yu‐Li Su Kun‐Chang Kuo Jyh‐Cherng Shieh Joe‐Air Jiang 《Progress in Photovoltaics: Research and Applications》2015,23(7):847-861
Environmental conditions, such as temperature, non‐uniform irradiation, and solar shading, deeply affect the characteristics of photovoltaic (PV) modules in PV‐assisted generation systems. Several local maximum power points (MPPs) are found in the power–voltage curve of PV systems constructed by series/parallel‐connected PV modules under partially shaded conditions. The characteristics of PV systems change unpredictably when multiple MPPs occur, so the actual MPP tracking (MPPT) becomes a difficult task. Conventional MPPT methods for the PV systems under partially shaded conditions cannot quickly find the actual MPP such that the optimal utilization of PV systems cannot be achieved. Based on the p–n junction semiconductor theory, we develop a multipoint direct‐estimation (MPDE) method to directly estimate the multiple MPPs of the PV systems under partially shaded conditions and to cope with the mentioned difficulties. Using the proposed MPDE method, the multiple MPPs of the PV systems under partially shaded conditions can be directly determined from their irradiated current–voltage and power–voltage characteristic curves. The performances of the proposed MPDE method are evaluated by examining the characteristics of multiple MPPs of PV systems with respect to different shading strengths and numbers of the shaded PV modules and also tested using the field data. The experimental results demonstrate that the proposed MPDE method can simply and accurately estimate the multiple MPPs of the PV systems under partially shaded conditions. The optimization of MPP control models and the MPPT for PV systems could be achieved promisingly by applying the proposed method. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
45.
46.
基于单电子隧道结电压特征公式[1],借助Matlab拟合其隧穿特性曲线,给出了时不变和时变偏置电流作用下的I-V特性震荡曲线,并就仿真结果进行分析,将该模型应用于单电子盒进行仿真验证,出现了明显的库仑台阶,仿真曲线印证了理论分析结果.利用Matab强大的计算功能进行单电子器件特性仿真对单电子器件的应用研究有重要意义. 相似文献
47.
TheⅢ-Ⅴcompound tandem solar cell is a third-generation new style solar cell with ultra-high efficiency. The energy band gaps of the sub-cells in a GaInP/GaAs/InGaAs/Ge 4-J tandem solar cell are 1.8,1.4,1.0 and 0.7 eV,respectively.In order to match the currents between sub-cells,tunnel junctions are used to connect the sub-cells.The characteristics of the tunnel junction,the material used in the tunnel junction,the compensation of the tunnel junction to the overall cell’s characteristics,the tunnel junction’s influence on the current density of sub-cells and the efficiency increase are discussed in the paper.An AlGaAs/GaAs tunnel junction is selected to simulate the cell’s overall characteristics by PC1D,current densities of 16.02,17.12,17.75 and 17.45 mA/cm2 are observed,with a Voc of 3.246 V,the energy conversion efficiency under AM0 is 33.9%. 相似文献
48.
负信噪比直扩信号伪码盲估计方法 总被引:1,自引:0,他引:1
给出了一种采用延迟相关积累和信号子空间分析实现对负信噪比直扩(DSSS)信号伪码盲估计的方法。计算机仿真结果表明,该方法可以在-15dB信噪比条件下检测信号并估计出伪码、载波频率等参数,估计结果可以实现非合作解扩解调。 相似文献
49.
4H-SiC junction barrier Schottky(JBS)diodes with four kinds of design have been fabricated and characterized using two different processes in which one is fabricated by making the P-type ohmic contact of the anode independently,and the other is processed by depositing a Schottky metal multi-layer on the whole anode.The reverse performances are compared to find the influences of these factors.The results show that JBS diodes with field guard rings have a lower reverse current density and a higher breakdown voltage,and with independent P-type ohmic contact manufacturing,the reverse performance of 4H-SiC JBS diodes can be improved effectively. Furthermore,the P-type ohmic contact is studied in this work. 相似文献
50.
The continuous shrinking of HgCdTe device dimensions in micro- and opto-electronics requires the development of new non-destructive
methods able to determine the quality of etching techniques, junction integrity, doping profiles, and the presence of electrically
active defects with nanometer resolution. In this paper, we have used a contactless contrast imaging technique to examine
junction integrity and recombination activity in n-on-p HgCdTe mid-wave infrared (MWIR) photodiodes. This method allows the
direct imaging of junctions, type conversions, dislocation densities, and diffusion profiles as an electromorphological map
of the wafer. Experimental and theoretical laser-beam induced current (LBIC) analysis have been used to confirm the results
of imaging studies, and to elucidate the effects of the electron beam on the device structure and integrity. 相似文献