维普中文期刊产品整合服务
10篇 您的检索式:作者名="T.R.Lenka"
    题名 作者 年代 出处 被引量
1Modeling and simulation of enhancement mode p-GaN Gate AlGaN/GaN HEMT for RF circuit switch applications显示文摘An enhancement mode p-GaN gate AlGaN/GaN HEMT is proposed and a physics based virtual source charge model with Landauer approach for electron transport has been developed using Verilog-A and simulated using Cadence Spectre,in order to predict device characteristics such as threshold voltage,drain current and gate capacitance.The drain current model incorporates important physical effects such as velocity saturation,short channel effects like DIBL(drain induced barrier lowering),channel length modulation(CLM),and mobility degradation due to self-heating.The predicted I_d–V_(ds),I_d–V_(gs),and C–V characteristics show an excellent agreement with the experimental data for both drain current and capacitance which validate the model.The developed model was then utilized to design and simulate a single-pole single-throw(SPST)RF switch.D.K.Panda T.R.Lenka 2017Journal of Semiconductors2017,38,6:5
2Impact of barrier thickness on gate capacitance—modeling and comparative analysis of GaN based MOSHEMTs显示文摘A mathematical model is developed predicting the behavior of gate capacitance with the nanoscale variation of barrier thickness in AlN/GaN MOSHEMT and its effect on gate capacitances of AlInN/GaN and AlGaN/GaN MOSHEMTs through TCAD simulations is compared analytically. Al N/GaN and AlInN/GaN MOSHEMTs have an advantage of a significant decrease in gate capacitance up to 108 fF/ m2 with an increase in barrier thickness up to 10 nm as compared to conventional AlGaN/GaN MOSHEMT. This decrease in gate capacitance leads to improved RF performance and hence reduced propagation delay.Kanjalochan Jena Raghunandan Swain T.R.Lenka 2015Journal of Semiconductors2015,36,3:2
3Model development for analyzing 2DEG sheet charge density and threshold voltage considering interface DOS for AlInN/GaN MOSHEMT显示文摘A model predicting the behavior of various parameters, such as 2DEG sheet charge density and threshold voltage, with the variation of barrier thickness and oxide thickness considering interface density of states is presented. The mathematical dependence of these parameters is derived in conjunction with the interface density of states. The dependence of sheet charge density with the barrier thickness and with the oxide thickness is plotted and an insight into the barrier scaling properties of Al In N based MOSHEMTs is presented. The threshold voltage is also plotted with respect to barrier thickness and oxide thickness, which reveals the possibility of the enhancement mode operation of the device at low values of the interface DOS. The results are in good agreement with the fabricated device available in the literature.Devashish Pandey T.R.Lenka 2014Journal of Semiconductors2014,35,10:2
4Small-signal model parameter extraction of E-mode N-polar GaN MOS-HEMT using optimization algorithms and its comparison显示文摘An improved small-signal parameter extraction technique for short channel enhancement-mode N-polar GaN MOS-HEMT is proposed, which is a combination of a conventional analytical method and optimization techniques. The extrinsic parameters such as parasitic capacitance, inductance and resistance are extracted under the pinch-off condition. The intrinsic parameters of the small-signal equivalent circuit(SSEC) have been extracted including gate forward and backward conductance. Different optimization algorithms such as PSO, Quasi Newton and Firefly optimization algorithm is applied to the extracted parameters to minimize the error between modeled and measured S-parameters. The different optimized SSEC models have been validated by comparing the S-parameters and unity current-gain with TCAD simulations and available experimental data from the literature. It is observed that the Firefly algorithm based optimization approach accurately extracts the small-signal model parameters as compared to other optimization algorithm techniques with a minimum error percentage of 1.3%.d.k.panda g.amarnath t.r.lenka 2018Journal of Semiconductors2018,39,7:2
5Modeling on oxide dependent 2DEG sheet charge density and threshold voltage in AlGaN/GaN MOSHEMT显示文摘We have developed a physics based analytical model for the calculation of threshold voltage, two dimensional electron gas(2DEG) density and surface potential for Al Ga N/Ga N metal oxide semiconductor high electron mobility transistors(MOSHEMT). The developed model includes important parameters like polarization charge density at oxide/Al Ga N and Al Ga N/Ga N interfaces, interfacial defect oxide charges and donor charges at the surface of the Al Ga N barrier. The effects of two different gate oxides(Al_2O_3 and HfO_2/ are compared for the performance evaluation of the proposed MOSHEMT. The MOSHEMTs with Al_2O_3 dielectric have an advantage of significant increase in 2DEG up to 1.2 10^(13) cm^2 with an increase in oxide thickness up to 10 nm as compared to HfO_2 dielectric MOSHEMT. The surface potential for HfO_2 based device decreases from 2 to –1.6 e V within10 nm of oxide thickness whereas for the Al_2O_3 based device a sharp transition of surface potential occurs from 2.8to –8.3 e V. The variation in oxide thickness and gate metal work function of the proposed MOSHEMT shifts the threshold voltage from negative to positive realizing the enhanced mode operation. Further to validate the model,the device is simulated in Silvaco Technology Computer Aided Design(TCAD) showing good agreement with the proposed model results. The accuracy of the developed calculations of the proposed model can be used to develop a complete physics based 2DEG sheet charge density and threshold voltage model for Ga N MOSHEMT devices for performance analysis.J.Panda K.Jena R.Swain T.R.Lenka 2016Journal of Semiconductors2016,37,4:1
6Performance analysis of 20 nm gate-length In_(0:2)Al_(0:8)N/GaN HEMT with Cu-gate having a remarkable high I_(ON)/I_(OFF)ratio显示文摘We propose a new structure of InxAl1..xN/GaN high electron mobility transistor(HEMT) with gate length of 20 nm. The threshold voltage of this HEMT is achieved as –0.472 V. In this device the InAlN barrier layer is intentionally n-doped to boost the ION/IOFF ratio. The InAlN layer acts as donor barrier layer for this HEMT which exhibits an ION D 10..4:3 A and a very low IOFF D 10..14:4 A resulting in an ION/IOFF ratio of1010:1. We compared our obtained results with the conventional InAlN/GaN HEMT device having undoped barrier and found that the proposed device has almost 105 times better ION/IOFF ratio. Further, the mobility analysis in GaN channel of this proposed HEMT structure along with DC analysis, C–V and conductance characteristics by using small-signal analysis are also presented in this paper. Moreover, the shifts in threshold voltage by DIBL effect and gate leakage current in the proposed HEMT are also discussed. InAlN was chosen as the most preferred barrier layer as a replacement of AlGaN for its excellent thermal conductivity and very good scalability.A.Bhattacharjee T.R.Lenka 2014Journal of Semiconductors2014,35,6:1
7Effect of metal-fingers/doped-ZnO transparent electrode on performance of GaN/InGaN solar cell显示文摘The effect of doped-ZnO transparent conductive oxide(TCO) with metal(Ag)-fingers contact on Ga N/In Ga N solar cell is investigated through numerical simulations. An optical and electrical analysis of different dopant elements(such as B, Al, Ga, In and Sn) with ZnO as a top TCO layer is studied. A comparative analysis of metal square pad electrode, metal grid pattern electrode and metal-finger/ZnO type electrodes are taken into consideration to ensure the effect of anti-reflectivity by ZnO. The effect of thickness of ZnO and i-In GaN layer on performance of solar cell is also studied in detail. The proposed solar cell structure with Ag-fingers/ZnO:Al as top contact electrode shows interesting device characteristics compared to other dopants and metal top electrodes.The device achieves open circuit voltage ~2.525 V, short circuit current ~4.256 mA/cm^2, fill factor ~87.86% and efficiency ~9.22% under 1 Sun, air mass 1.5 global illumination.S.R.Routray T.R.Lenka 2017Journal of Semiconductors2017,38,9:0
8Analysis of morphological,structural and electrical properties of annealed TiO2 nanowires deposited by GLAD technique显示文摘The effect of annealing on vertically aligned TiO_2 NWs deposited by glancing angle deposition(GLAD)method on Si substrate using pressed and sintered TiO_2 pellets as source material is studied.The FE-SEM images reveal the retention of vertically aligned NWs on Si substrate after annealing process.The EDS analysis of TiO_2NWs sample annealed at 600 ℃ in air for 1 h shows the higher weight percentage ratio of ~2.6(i.e.,72.27%oxygen and 27.73%titanium).The XRD pattern reveals that the polycrystalline nature of anatase TiO_2 dominates the annealed NWs sample.The electrical characteristics of Al/TiO_2-NWs/TiO_2-TF/p-Si(NW device) and Al/TiO_2-TF/p-Si(TF device) based on annealed samples are compared.It is riveting to observe a lower leakage current of ~1.32 × 10^(-7) A/cm^2 at +1 V with interface trap density of-6.71 × 10^(11)eV^(-1)cm^(-2)in NW device compared to ~2.23 × 10^(-2) A/cm^2 in TF device.The dominant leakage mechanism is investigated to be generally Schottky emission;however Poole-Frenkel emission also takes place during high reverse bias beyond 4 V for NWs and 3 V for TF device.B.Shougaijam R.Swain C.Ngangbam T.R.Lenka 2017Journal of Semiconductors2017,38,5:0
9RF and microwave characteristics of a 10 nm thick InGaN-channel gate recessed HEMT显示文摘A new depletion-mode gate recessed AlGaN/InGaN/GaN-high electron mobility transistor(HEMT)with 10 nm thickness of InGaN-channel is proposed.A growth of AlGaN over GaN leads to the formation of twodimensional electron gas(2DEG)at the heterointerface.High 2DEG density(ns)is achieved at the heterointerface due to a strain induced piezoelectric effect between AlGaN and GaN layers.The electrons are confined in the InGaN-channel without spilling over into the buffer layer,which also reduces the buffer leakage current.From the input transfer characteristics the threshold voltage is obtained as 4:5 V and the device conducts a current of 2 A/mm at a drain voltage of 10 V.The device also shows a maximum output current density of 1.8 A/mm at Vds of 3 V.The microwave characteristics like transconductance,cut-off frequency,max frequency of oscillation and Mason’s Unilateral Gain of the device are studied by AC small-signal analysis using a two-port network.The stability and power performance of the device are analyzed by the Smith chart and polar plots respectively.To our knowledge this proposed InGaN-channel HEMT structure is the first of its kind.T.R.Lenka G.N.Dash A.K.Panda 2013Journal of Semiconductors2013,34,11:0
10Investigation of current collapse and recovery time due to deep level defect traps inβ-Ga2O3 HEMT显示文摘In this paper,drain current transient characteristics ofβ-Ga2O3 high electron mobility transistor(HEMT)are studied to access current collapse and recovery time due to dynamic population and de-population of deep level traps and interface traps.An approximately 10 min,and 1 h of recovery time to steady-state drain current value is measured under 1 ms of stress on the gate and drain electrodes due to iron(Fe)–dopedβ-Ga2O3 substrate and germanium(Ge)–dopedβ-Ga2O3 epitaxial layer respectively.On-state current lag is more severe due to widely reported defect trap EC–0.82 e V over EC–0.78 e V,-0.75 e V present in Iron(Fe)-dopedβ-Ga2O3 bulk crystals.A negligible amount of current degradation is observed in the latter case due to the trap level at EC–0.98 e V.It is found that occupancy of ionized trap density varied mostly under the gate and gate–source area.This investigation of reversible current collapse phenomenon and assessment of recovery time inβ-Ga2O3 HEMT is carried out through 2 D device simulations using appropriate velocity and charge transport models.This work can further help in the proper characterization ofβ-Ga2O3 devices to understand temporary and permanent device degradation.R.Singh T.R.Lenka R.T.Velpula B.Jain H.Q.T.Bui H.P.T.Nguyen 2020Journal of Semiconductors2020,41,10:0
返回顶部 每页显示:
共1页 首页 上一页 第1页 下一页 末页 /1 跳转

网站首页 | 关于我们 | 联系我们 | 产品服务 | 客服中心 | 广告服务 | 版权声明 | 网站联盟 | 友情链接 | 售卡网点

版权所有© 渝B2-20050021-1 渝公网安备 50019002500403号 违法和不良信息举报中心

互联网出版许可证 新出网证(渝)字10号 全国400电话 - 免长途话费