深亚微米nMOSFET器件的总剂量电离辐射效应

选取了采用0.25μm工艺的两组器件进行研究.通过对这两种器件关态泄漏电流、跨导和栅电流等电学参数进行分析,得出当器件发展到深亚微米阶段时,影响其辐射效应的主要原因是场氧化层中的陷阱电荷.并对相关机理进行了分析和仿真验证.     

SiGe HBT 60Co γ辐照总剂量效应

测量了SiGe HBT直流增益在60Coγ辐照过程中随剂量及器件电流注入水平的变化。实验结果显示在累计辐照剂量超过5 000 Gy(Si)后,器件电流增益变化与辐照剂量存在线性反比关系,且增益损伤系数与器件电流注入水平有关;器件在受到总剂量为2.78×104Gy(Si)辐照后,器件静态基极电流Ib、集电极电流Ic、静态直流增益及最大振荡频率fmax出现不同程度退化;但器件其他电参数如截止频率fT、交流增益|H21|及结电容(CCBO)与辐照前相比未出现显著退化。利用MEDICI数值模拟分析了SiGe HBT参数退化机理。     

GaN基LED电流扩展对其器件特性的影响

GaN基LED的表面电流扩展对于器件的特性起着很重要的作用.制作环状N电极的器件在正向电压、总辐射功率、器件老化等特性方面较普通的电极都有很大的提高.通过一系列的实验对环状N电极和普通电极进行了比较,在外加正向电流为20 mA时,正向电压减小了6%,总辐射功率也略有提高,工作50小时后,总辐射功率相差8%,验证了环状N电极结构有利于器件电流扩展,减少器件串联电阻,减少了焦耳热的产生,提高了LED电光特性和可靠性.     

不同钝化层结构的长波碲镉汞光伏探测器的γ辐照效应

对采用单层ZnS和双层CdTe/ZnS两种钝化层结构的长波碲镉汞光伏器件进行了实时γ辐照效应研究.通过辐照过程中实时测试器件的电流-电压特性,发现随着辐照剂量的增加,两种器件表现出不同的辐照效应.结合光伏器件的电流机制分析,对器件的电阻-电压曲线进行数值拟合,发现器件的主要电流机制在偏压较大时为间接隧道电流,在偏压较小及零偏压附近时为产生-复合电流.对辐照前后器件的电阻-电压曲线进行对比分析,认为CdTe/ZnS双层钝化结构有助于降低辐照位移效应的影响,使得器件间接隧道电流随辐照剂量无明显的增加;同时发现辐照电离效应的影响与器件材料的初始性能参数密切相关,拟合得到ZnS单层钝化结构的器件具有较高的少子产生-复合寿命,受电离效应的影响较大,导致其产生-复合电流随着辐照剂量增加持续增大.     

高压MOS晶体管双峰衬底电流分析及优化

利用0.15 μm标准CMOS工艺制造出了工作电压为30 V的双扩散漏端MOS晶体管.观察到DDDMOS的衬底电流-栅压曲线有两个峰.实验表明,DDDMOS衬底电流的第二个峰对器件的可靠性有一定的影响.利用TCAD模拟解释了DDDMOS第二个衬底电流峰的形成机制,并通过求解泊松方程和电流连续性方程分析了器件的物理和几何参数与第二个衬底电流峰之间的关系.根据分析的结果优化了制造工艺,降低了DDDMOS的衬底电流,提高了器件的可靠性.     

不同偏置下全耗尽SOI NMOSFET总剂量抗辐射的研究

研究了不同偏置条件下,全耗尽SOI NMOSFET的总剂量抗辐射特性,主要讨论不同偏置条件对器件中陷获电荷的产生和分布,以及由此对器件性能产生的影响.通过器件模拟发现,在辐射过程中器件的偏置条件不同,造成器件的有源区和埋氧层中电场的分布有着很大的差异.而俘获电荷的产生与电场又有着紧密的联系,所以造成了俘获电荷的分布和密度有很大的不同,从而对器件的影响也不同.模拟结果表明,在三种不同的偏置条件下,OFF态(关态)时背沟道附近陷获电荷密度最高,以常数电流法估算出的阈值电压负漂移最大,同时引起了最大的本底静态漏电流.     

双极晶体管发射极电阻的提取方法及应用研究

以双多晶自对准互补双极器件中NPN双极晶体管为例,阐述了发射极电阻提取的基本原理和数学方法。在大电流情况下,NPN管的基极电流偏离理想电流是发射极串联电阻效应引起的。该提取方法综合考虑了辐照过程中NPN管的电流增益退化特性,分析了总剂量辐照效应对NPN管的损伤机理和模式。该提取方法适用于多晶硅发射极器件,也适用于SiGe HBT器件。     

不同偏置下全耗尽SOI NMOSFET总剂量抗辐射的研究

研究了不同偏置条件下,全耗尽SOI NMOSFET的总剂量抗辐射特性,主要讨论不同偏置条件对器件中陷获电荷的产生和分布,以及由此对器件性能产生的影响.通过器件模拟发现,在辐射过程中器件的偏置条件不同,造成器件的有源区和埋氧层中电场的分布有着很大的差异.而俘获电荷的产生与电场又有着紧密的联系,所以造成了俘获电荷的分布和密度有很大的不同,从而对器件的影响也不同.模拟结果表明,在三种不同的偏置条件下,OFF态（关态）时背沟道附近陷获电荷密度最高,以常数电流法估算出的阈值电压负漂移最大,同时引起了最大的本底静态漏电流.     

SiGe HBT直流电流增益模型研究

基于器件结构特点和电学特性,研究了影响SiGe HBT(异质结双极晶体管)直流电流增益的主要因素,分析了不同的电流密度条件下,器件的物理参数、结构参数与集电极电流密度和中性基区复合电流的关系,建立了SiGe HBT集电极电流密度,空穴反注入电流密度、中性基区复合电流、SRH(Shockley-Read- Hall)复合电流密度、俄歇复合电流密度以及直流电流增益模型,对直流电流增益模型进行了模拟仿真,分析了器件物理、结构参数以及复合电流与直流电流增益的关系,得到了SiGe HBT直流电流增益特性的优化理论依据.     

超高总剂量辐射下SOI MOS器件特性研究

在超高总剂量辐射下,界面电荷的改变对MOS器件的阈值电压影响将越来越显著,甚至会引起NMOS的阈值电压增加,即所谓的“反弹”现象。文章研究的SOI NMOS的阈值电压并没有出现文献中所述的“反弹”,原因可能和具体的工艺有关。另外,通过工艺器件仿真和辐射试验验证,SOI器件在超高总剂量辐射后的漏电不仅仅来自于闽值电压漂移所导致的背栅甚至前栅的漏电流,而是主要来自于前栅的界面态的影响。这样,单纯的对埋层SiO2进行加固来减少总剂量辐射后埋层SiO2中的陷阱正电荷,并不能有效提高SOI MOS器件的抗超高总剂量辐射性能。     

Cost-effective test solutions for smart card and other integrated flash applications

From its emergence in the late 1980s as a lower cost alternative to early EEPROM technologies, flash memory has evolved to higher densities and speedsand rapidly growing acceptance in mobile applications.In the process, flash memory devices have placed increased test requirements on manufacturers. Today, as flash device test grows in importance in China, manufacturers face growing pressure for reduced cost-oftest, increased throughput and greater return on investment for test equipment. At the same time, the move to integrated flash packages for contactless smart card applications adds a significant further challenge to manufacturers seeking rapid, low-cost test.     

An improved parallel thinning algorithm with two subiterations

The parallel thinning algorithm with two subiterations is improved in this paper. By analyzing the notions of connected components and passes, a conclusion is drawn that the number of passes and the number of eight-connected components are equal. Then the expression of the number of eight-connected components is obtained which replaces the old one in the algorithm. And a reserving condition is proposed by experiments, which alleviates the excess deletion where a diagonal line and a beeline intersect. The experimental results demonstrate that the thinned curve is almost located in the middle of the original curve connectivelv with single pixel width and the processing speed is high.     

Theoretical analysis of the relationship between the Brillouin gain coefficient and the strain in the optical-fiber sensors

The relation between the power of the Brillouin signal and the strain is one of the bases of the distributed fiber sensors of temperature and strain. The coefficient of the Bfillouin gain can be changed by the temperature and the strain that will affect the power of the Brillouin scattering. The relation between the change of the Brillouin gain coefficient and the strain is thought to be linear by many researchers. However, it is not always linear based on the theoretical analysis and numerical simulation. Therefore, errors will be caused if the relation between the change of the Brillouin gain coefficient and the strain is regarded as to be linear approximately for measuring the temperature and the strain. For this reason, the influence of the parameters on the Brillouin gain coefficient is proposed through theoretical analysis and numerical simulation.     

Novel fiber-optical interferometer with miniaturized probe for in-hole measurements

Today, micro-system technology and the development of new MEMS （Micro-Electro-Mechanical Systems） are emerging rapidly. In order for this development to become a success in the long run, measurement systems have to ensure product quality. Most often, MEMS have to be tested by means of functionality or destructive tests. One reason for this is that there are no suitable systems or sensing probes available which can be used for the measurement of quasi inaccessible features like small holes or cavities. We present a measurement system that could be used for these kinds of measurements. The system combines a fiber optical, miniaturized sensing probe with low-coherence interferometry, so that absolute distance measurements with nanometer accuracy are possible.     

Teleportation of an arbitrary unknown N-qubit entangled state under the controlling of M controllers

A new quantum protocol to teleport an arbitrary unknown N-qubit entangled state from a sender to a fixed receiver under M controllers(M < N) is proposed. The quantum resources required are M non-maximally entangled Greenberger-Home-Zeilinger (GHZ) state and N-M non-maximally entangled Einstein-Podolsky-Rosen (EPR) pairs. The sender performs N generalized Bell-state measurements on the 2N particles. Controllers take M single-particle measurement along x-axis, and the receiver needs to introduce one auxiliary two-level particle to extract quantum information probabilistically with the fidelity unit if controllers cooperate with it.     

Diode-end-pumped Nd:YVO4/LBO lasers with 4.2W continuous-wave output at 457 nm

A continuous-wave (CW) 457 nm blue laser operating at the power of 4.2 W is demonstrated by using a fiber coupled laser diode module pumped Nd: YVO4 and using LBO as the intra-cavity SHG crystal With the optimization of laser cavity and crystal parameters, the laser operates at a very high efficiency. When the pumping power is about 31 W, the output at 457nm reaches 4.2 W, and the optical to optical conversion efficiency is about 13.5% accordingly. The stability of the out putpower is better than 1.2% for 8 h continuously working.     

Call for Papers

正Wireless Body-area Networks The last decade has witnessed the convergence of three giant worlds:electronics,computer science and telecommunications.The next decade should follow this convergence in most of our activities with the generalization of sensor networks.In particular with the progress in medicine,people live longer and the aging of population will push the development of wireless personal networks     

Call for Papers—Feature Topic,Vol.12,No.7,2015

正Information Centric Networking Information-Centric Networking(ICN) is an emerging direction in Future Internet architecture research,gaining significant tractions among academia and industry.Aiming to replace the conventional host-to-host communication model by a data-centric model,ICN treats data content as the first     

JOURNAL OF ELECTRONICS(CHINA)

正~~     

NEXT GENERATION WIRELESS NETWORKS–ESPECIALLY THE USE OF MILLI-MICROWAVE BANDS

The global bandwidth shortage of wireless communications has motivated the exploration of the naillimeter wave （ram-wave） frequency spectrum for the next generation wireless communications. Recent advances in RF CMOS technology and high speed baseband signal processing technologies have enabled tile extensive research and development of turn-wave wireless communications. The multi gigabit per second data rate of ram-wave system will lead to applications in many important scenarios, such as WPAN, WLAN,back-haul for cellular system. And the frequency bands include 28 GHz, 38 GHz, 45GHz, 60GHz, E-BAND and even beyond 100 GHz. The propagation and the imitation of the RF circuits design in these frequency bands make the directional antennas be inevitable for mm-wave communications.