西安电子科技大学 微电子学院 宽禁带半导体国家重点实验室，西安 710071
随着电磁环境的日益复杂，保证集成电路（IC）的可靠性成为一个巨大的挑战。在此基础上，通过对CMOS反相器的仿真和实验研究，研究了快上升沿电磁脉冲（EMP）引起的陷阱辅助隧穿（TAT）效应。对此进行了详细的机理分析用于解释其物理损伤过程。EMP感应电场在氧化层中产生陷阱和泄漏电流，从而导致器件的输出退化和热失效。建立了退化和失效的理论模型，以描述输出退化及热积累对EMP特征的依赖性。温度分布函数由半导体中的热传导方程导出。基于TLP测试系统进行的相应实验证实了出现的性能退化，与机理分析一致。Sentaurus TCAD的仿真结果表明，EMP引起的损坏是由栅极氧化层中发生的TAT电流路径引起的，这也是器件的易烧坏位置。此外，还讨论了器件失效与脉冲上升沿的关系。本文的机理分析有助于加强其他半导体器件的EMP可靠性研究，可以对CMOS数字集成电路的EMP加固提出建议。
CMOS反相器 电磁脉冲 陷阱辅助隧穿 机理分析 CMOS inverter electromagnetic pulse trap-assisted tunneling mechanism analysis 强激光与粒子束
2022, 34(8): 083002
强激光与粒子束
2021, 33(10): 103006
西安电子科技大学 微电子学院, 教育部宽禁带半导体材料与器件重点实验室, 西安 710071
建立了三种不同结构的硅基单片式复合晶体管(由T1和T2两个晶体管构成)的二维电热模型, 研究了高功率微波对不同结构的硅基单片式复合晶体管的损伤效应的影响。获得了不同器件结构下导致复合晶体管损伤的损伤功率阈值和损伤能量阈值分别与脉宽的关系。结果表明, 当复合晶体管的总体尺寸不变而T2和T1晶体管的面积比值更大时需要更多的功率和能量来损伤器件。通过分析器件内部电场、电流密度和温度分布的变化, 得到了复合晶体管的结构对其微波损伤效应的影响规律。对比发现, 三种结构的复合晶体管的损伤点均位于T2管的发射极附近, 随着T2和T1晶体管面积比的增大, 电场、电流密度和温度在器件内部的分布将变得更加分散。此外, 在发射极处增加外接电阻Re, 研究表明损伤时间随发射极电阻的增大而增加。因此可以得出结论, 适当改变器件结构或增加外接元件可以增强器件的抗微波损伤能力。晶体管的仿真毁伤点与实验结果一致。
单片式复合晶体管 高功率微波 器件结构 外加元件 monolithic composite transistor high power microwave device structures external component 强激光与粒子束
2019, 31(10): 103220
西安电子科技大学 微电子学院, 教育部宽禁带半导体材料与器件重点实验室, 西安 710071
建立了PNP型达林顿管的二维电热模型，对处于有源放大区的达林顿管的集电极注入高功率微波（HPM）和强电磁脉冲（EMP）时的瞬态响应进行了仿真。结果表明：HPM注入下，器件内部的峰值温度呈周期性的“下降-上升”，温度升高过程发生在信号的正半周，靠近达林顿管发射极的晶体管发射结边缘是最易毁伤处；EMP注入下，其损伤机理与HPM注入时的正半周时相似，器件内部峰值温度一直上升，易毁伤部位与HPM注入时相同。得到了损伤功率阈值和损伤能量阈值与损伤脉宽的关系，这两种干扰注入下的损伤能量阈值-脉宽关系和损伤功率阈值-脉宽关系公式相似，并且在相同脉宽下，HPM注入下的损伤能量阈值大于EMP注入下的损伤能量阈值。
达林顿管 高功率微波 强电磁脉冲 脉宽效应 Darlington tube high power microwave electromagnetic pulse pulse width effect 强激光与粒子束
2018, 30(8): 083008
Author Affiliations
Abstract
1 School of Computer Science and Technology, Xidian University, Xi’an 710071, China
2 State Key Laboratory of Integrated Service Networks, School of Telecommunications Engineering, Xidian University, Xi’an 710071, China
3 Southwest China Research Institute of Electronic Equipment, Chengdu 610036, China
4 Key Laboratory of the Ministry of Education for Wide Band-Gap Semiconductor Materials and Devices, School of Microelectronics, Xidian University, Xi’an 710071, China
5 School of Physics and Optoelectronic Engineering, Xidian University, Xi’an 710071, China
The symbol error rate (SER) performance of a multipulse pulse-position modulation (MPPM) free space optical (FSO) system under the combined effect of turbulence-induced fading modeled by exponentiated Weibull (EW) distribution and pointing errors with a soft-decision detector is investigated systematically. Particularly, the theoretical conditional SER (CSER) of soft-decision decoded MPPM is derived. The corresponding closed-form CSER is obtained via curve fitting with the Levenberg–Marquardt method. The analytical SER expression over the aggregated fading channels is then achieved in terms of Laguerre integration. Monte Carlo simulation results are also offered to corroborate the validity of the proposed SER model.
060.2605 Free-space optical communication 010.1300 Atmospheric propagation 010.1330 Atmospheric turbulence Chinese Optics Letters
2017, 15(5): 050602
Author Affiliations
Abstract
1 State Key Laboratory of Integrated Service Networks, School of Telecommunications Engineering, Xidian University, Xi’an 710071, China
2 School of Physics and Optoelectronic Engineering, Xidian University, Xi’an 710071, China
3 Key Laboratory of the Ministry of Education for Wide Band-Gap Semiconductor Materials and Devices, School of Microelectronics, Xidian University, Xi’an 710071, China
The average bit error rate (BER) performance of a free-space optical (FOS) system based on the multi-hop parallel decode-and-forward cooperative communication method with an M-ary phase shift keying subcarrier intensity modulation is studied systematically. With the max–min criterion as the best path selection scheme, the probability density function and the cumulative distribution function of the gamma–gamma distribution random variable signal-to-noise ratio are derived. The analytical BER expression is then obtained in terms of the Gauss–Laguerre quadrature rule. Monte Carlo simulation is also provided to confirm the validity of the presented average BER model.
010.1300 Atmospheric propagation 010.1330 Atmospheric turbulence 060.2605 Free-space optical communication 060.4251 Networks, assignment and routing algorithms Chinese Optics Letters
2015, 13(8): 080101
1 西安电子科技大学微电子学院, 陕西 西安 710071
2 西安电子科技大学技术物理学院, 陕西 西安 710071
针对红外焦平面阵列(IRFPA)中探测元的非线性响应以及响应特性的漂移引起的校正误差, 提出了一种基于S曲线模型的场景自适应校正算法。该算法利用对数运算将IRFPA的输出信号线性化, 并运用自适应滤波技术对线性信号实施非均匀性校正, 并采用指数变换还原出实际的校正输出信号。基于人造黑体图像和实景红外视频的仿真实验结果表明, 该算法在校正精度和大动态范围信号响应特性方面均优于传统的场景自适应校正算法。
红外焦平面阵列 非均匀性校正 非线性响应模型 自适应滤波
Author Affiliations
Abstract
School of Microelectronics, Xidian University, Key Lab of Ministry of Education for Wide Bandgap Semiconductor Materials and Devices, Xi'an 710071
The current-voltage (I-V) characteristics of 4H-SiC metal-semiconductor-metal (MSM) ultraviolet photodetector with different finger widths and spacings, different carrier concentrations and thicknesses of n-type epitaxial layer are simulated. The simulation results indicate that the dark current and the photocurrent both increase when the finger width increases. But the effect of finger width on the dark current is more significant. On the other hand, the effect of finger spacing on the photocurrent is more significant. When the finger spacing increases, the photocurrent decreases and the dark current is almost changeless. In addition, it is found that the smaller the carrier concentration of n-type epitaxial layer is, the smaller the dark current and the larger the photocurrent will be. It is also found that I-V characteristics of MSM detector also depend on the epitaxial layer thickness. The dark current of detector is smaller and the photocurrent is larger when the epitaxial layer thickness is about 3 \mum.
紫外探测器 4H-SiC 金属-半导体-金属(MSM) 040.5160 Photodetectors 250.0250 Optoelectronics 160.6000 Semiconductor materials Chinese Optics Letters
2008, 6(8): 615
西安电子科技大学微电子学院 宽禁带半导体材料与器件教育部重点实验室, 陕西 西安 710071
用MEDICI软件对金属-半导体-金属(MSM)结构4H-SiC紫外(UV)探测器的I-V特性以及光谱响应等特性进行了模拟与分析,并探讨了金属电极的宽度、电极间距以及外延层厚度对探测器响应度的影响。结果表明,室温下该探测器的暗电流线性密度达到10-13 A/μm,且在不同电压下光电流至少比暗电流大两个数量级; 探测器的光谱响应范围为200～400 nm,在347 nm处响应度达到极大值; 增大指宽或者减小指间距可以提高探测器的响应度; 当波长小于峰值波长时外延层厚度对探测器的响应度基本没影响,而当波长大于峰值波长时随着外延层厚度的增大探测器的响应度有所增大。
探测器 紫外探测器 模拟 金属-半导体-金属结构 光谱响应
1 西安电子科技大学,微电子研究所宽禁带半导体材料与器件教育部重点实验室,西安,710071
2 西北工业大学,材料科学与工程学院,西安,710072
采用传统固相反应法制备PZT铁电材料,并制作成平行平板无源电容器结构,在ELV-8电子直线加速器上进行了总剂量效应辐照实验.结果表明:样片经过不同强度高能高速直流电子束辐照后的电滞回线随着辐照强度的增加,电滞回线所包围的面积逐渐减小,饱和极化强度、剩余极化强度和矫顽场呈线性减小.其中当辐照剂量为1×108rad(Si)时,饱和极化强度、剩余极化强度和矫顽场的衰减幅度分别为14.1%,15.0%和2.7%,样片抗总剂量辐照能力可达1×108rad(Si).
铁电材料 电滞回线 总剂量辐照效应 抗辐照 强激光与粒子束
2007, 19(12): 2091
