内透明集电极绝缘栅双极晶体管温度特性的仿真研究

ITC-IGBT是新一类IGBT,它在PT-IGBT结构基础上,在集电区近集电结附近引入一局域载流子寿命控制(LCLC)层,只要该层内载流子寿命足够低,则LCLC层对其以下衬底内的空穴具有屏蔽作用,从而使集电区范围变窄、集电区电子有效扩散长度减小,可使器件集电区由非透明变成内透明。本论文首次对600V平面栅内透明集电极IGBT(ITC-IGBT)的温度特性进行了仿真研究,并与传统PT-IGBT进行了比较。仿真结果表明,ITC-IGBT不仅技术折衷曲线明显优于PT-IGBT,且电流零温度系数点以及关断损耗随温度的增加率也比PT-IGBT要低,这说明ITC-IGBT不仅具有优良的电参数指标,同时具有良好的热稳定性。是一类颇具潜力的低压快速IGBT。     

IGBT集电结局域寿命控制的比较与分析

新型的电场终止型绝缘栅双极晶体管(FS-IGBT)改善了传统穿通型(PT)IGBT性能上的不足,但对于1 200 V以下器件需要超薄片加工。为打破加工技术的限制,用简易的厚片工艺实现薄片性能,可以在集电结附近设置载流子局域寿命控制层(LCLC)来改善器件性能。目前有两种方案:将LCLC区置于集电区内形成内透明集电极IGBT(ITC-IGBT);或置于缓冲层内,形成缓冲层局域寿命控制IGBT。对这两种结构的600 V器件结合具体参数进行了仿真和比较。仿真结果表明,两种结构的器件可实现几近相同的折中特性,但当LCLC区位于缓冲层内时,需要更低的局域寿命,且更易发生通态特性的回跳现象,影响器件性能。因此将LCLC区置于集电区,即形成ITC-IGBT结构是一个更好的选择,为探索用厚片工艺制造高性能IGBT提供了必要的参考。     

仿真研究变掺杂缓冲层技术对MOSFET抗SEB能力的改善

内透明集电极(Internal Transparent Collector,简称ITC)绝缘栅双极晶体管(IGBT)是新一类IGBT,其特点是在传统穿通型(PT)IGBT结构基础上,在集电区近集电结附近引入一局域载流子寿命控制(LCLC)区,从物理上屏蔽厚衬底中空穴的注入,使集电区范围变窄、集电区少子有效扩散长度减小,器件集电区由非透明变成内透明。本论文针对600V平面栅ITC IGBT的短路特性进行仿真研究,重点讨论LCLC区的位置及LCLC区内载流子寿命对器件短路的影响。结果显示,对一定的载流子寿命,随着LCLC区距集电结距离减小,器件短路性能增强;而对固定的LCLC区位置,随着LCLC区内载流子寿命降低,器件短路性能进一步改善。所有这些最终都可以归结于背发射极效率的影响。     

电荷耦合内透明集电极IGBT设计与仿真北大核心CSCD

针对沟槽型绝缘栅双极型晶体管(IGBT)栅电容较大、开关速度较慢的问题,基于内透明集电极(ITC)技术,将电荷耦合(CC)的思想应用于槽栅IGBT中。采用仿真工具MEDICI对电荷耦合内透明集电极IGBT(CC-ITC-IGBT)的击穿特性、导通特性和开关特性等进行了仿真研究,重点研究了电荷耦合区掺杂浓度和局域载流子寿命控制区(LCLC)载流子寿命对器件性能的影响,并和普通的槽栅内透明集电极IGBT进行了对比。结果表明,在给定的参数范围内,新结构在快速关断区域折中特性曲线更好,在低导通压降区域,优势变得不太明显,因而电荷耦合内透明集电极IGBT更适合做快速关断型。     

一种新结构IGBT--内透明集电极IGBT的仿真

对新近提出的一种新结构的IGBT--内透明集电极IGBT进行了器件性能的仿真.这种IGBT是在传统非透明集电极IGBT结构基础上,通过在集电区内距离集电结很近处设置一个高复合层的方法,使器件在物理上实现了集电极对电子的透明,同时又避免了低压透明集电极IGBT制造过程中超薄片操作的技术难题.对器件的温度特性和关断特性进行了仿真研究,并与现行PT-IGBT和FS-IGBT进行了比较.仿真结果表明,通过合理调整内透明集电极IGBT的参数组合,可以使其在具有通态压降正温度系数的同时,又具有较快的关断速度,实现透明集电极IGBT的优良性能.     

一种新结构IGBT——内透明集电极IGBT的仿真

对新近提出的一种新结构的IGBT--内透明集电极IGBT进行了器件性能的仿真.这种IGBT是在传统非透明集电极IGBT结构基础上,通过在集电区内距离集电结很近处设置一个高复合层的方法,使器件在物理上实现了集电极对电子的透明,同时又避免了低压透明集电极IGBT制造过程中超薄片操作的技术难题.对器件的温度特性和关断特性进行了仿真研究,并与现行PT-IGBT和FS-IGBT进行了比较.仿真结果表明,通过合理调整内透明集电极IGBT的参数组合,可以使其在具有通态压降正温度系数的同时,又具有较快的关断速度,实现透明集电极IGBT的优良性能.     

600 V高性能新型槽栅内透明IGBT的仿真

载流子存储层(CSL)可以改善IGBT导通态载流子分布,降低通态电压,但影响器件阻断能力。为了平衡载流子存储层对器件阻断能力的影响,在器件n-漂移区中CSL层处近哑元胞侧设计了p型埋层(p BL),利用电荷平衡的理念改善电场分布,并借助ISE-TACD仿真工具,依托内透明集电极(ITC)技术,研究了600 V槽栅CSL-p BL-ITC-IGBT电特性。为了保证器件承受住不小于10μs的短路时间,设置了哑元胞。在此基础上,仿真分析了CSL和p BL的尺寸及掺杂浓度、哑元胞尺寸等对器件特性的影响,并与普通的槽栅ITC-IGBT、点注入局部窄台面(PNM)ITC-IGBT的主要技术指标进行对比,给出CSL和p BL的尺寸及掺杂浓度的最佳范围。结果表明,合理的参数设计可使CSL-p BL-ITC-IGBT具有更优的技术折中曲线。     

一种新结构IGBT——内透明集电区IGBT

本文对一种新的IGBT结构——“内透明集电区IGBT”（ITC-IGBT）进行了仿真研究。这种新结构的特点是在用外延片制造的传统的IGBT的P型集电区中距集电结很近的位置设置了一个具有极高过剩载流子复合速率的内部高复合层，同时适当降低高复合层以上P区掺杂浓度。仿真结果表明，无论是穿通型结构（有缓冲层）还是非穿通型结构（无缓冲层）的ITC—IGBT，在器件工作电流范围内都具有饱和电压正温度系数，解决了现有的用外延片制造的PT—IGBT所难以克服的饱和电压负温度系数的缺点，有利于IGBT的并联使用。对于1200V以下的IGBT，该新结构开辟了一种可以避免超薄片操作的简单的制造良好温度性能器件的途径。     

一种新结构IGBT——内透明集电极IGBT的仿真研究

本文首次对新近提出的一种新结构的IGBT——内透明集电极IGBT进行了器件性能的仿真。这种IGBT是在传统非透明集电极IGBT结构基础上,通过在集电区内距离集电结很近处设置一个高复合层的方法,使器件在物理上实现了集电极对电子的透明,同时又避免了低压透明集电极IGBT制造过程中超薄片操作的技术难题。论文重点对器件的温度特性和关断特性进行了仿真研究,并与现行PT-IGBT和FS-IGBT进行了比较。仿真结果表明,通过合理调整内透明集电极IGBT的参数组合,可以使其具有通态压降正温度系数的同时,又具有较快的关断速度,实现透明集电极IGBT的优良性能。     

一种具有低寿命区的阳极短路4H-SiCIGBT仿真研究

传统沟槽型4H-SiC IGBT中关断损耗较大,导通压降和关断损耗难以折中.针对此问题,文中提出了发射极区域含有低寿命区,同时集电区引入阶梯型集电极的LS-IGBT结构来降低器件的关断损耗.通过同时控制集电区注入的空穴载流子数量和P基区载流子的寿命,在基本维持器件击穿电压的前提下降低器件的关断损耗.使用Silvaco ...     

Resolution Enhancement Technology:Integrated Process Solutions using OPC

DUV lithography, using the 248 nm wavelength, is a viable manufacturing option for devices with features at 130 nm and less. Given the low kl value of the lithography, integrated process development is a necessary method for achieving acceptable process latitude. The application of assist features for rule based OPC requires the simultaneous optimization of the mask, illumination optics and the resist.Described in this paper are the details involved in optimizing each of these aspects for line and space imaging.A reference pitch is first chosen to determine how the optics will be set. The ideal sigma setting is determined by a simple geometrically derived expression. The inner and outer machine settings are determined, in turn,with the simulation of a figure of merit. The maximum value of the response surface of this FOM occurs at the optimal sigma settings. Experimental confirmation of this is shown in the paper.Assist features are used to modify the aerial image of the more isolated images on the mask. The effect that the diffraction of the scattering bars (SBs) has on the image intensity distribution is explained. Rules for determining the size and placement of SBs are also given.Resist is optimized for use with off-axis illumination and assist features. A general explanation of the material' s effect is discussed along with the affect on the through-pitch bias. The paper culminates with the showing of the lithographic results from the fully optimized system.     

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.     

Study of waveguide coupling efficiency in hybrid silicon lasers

This paper presents a new method to increase the waveguide coupling efficiency in hybrid silicon lasers. We find that the propagation constant of the InGaAsP emitting layer can be equal to that of the Si resonant layer through improving the design size of the InP waveguide. The coupling power achieves 42% of the total power in the hybrid lasers when the thickness of the bonding layer is 100 nm. Our result is very close to 50% of the total power reported by Intel when the thickness of the thin bonding layer is less than 5 nm. Therefore, our invariable coupling power technique is simpler than Intel＇s.     

A rigorous proof of MIMO channel capacity’s increase with antenna number

It is well known that adding more antennas at the transmitter or at the receiver may offer larger channel capacity in the multiple-input multiple-output（MIMO） communication systems. In this letter, a simple proof is presented for the fact that the channel capacity increases with an increase in the number of receiving antennas. The proof is based on the famous capacity formula of Foschini and Gans with matrix theory.     

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