双极器件中硅基区和锗硅基区的禁带变窄量

采用一种新的方法计算双极器件中离子注B硅基区和原位掺B的锗硅基区禁带变窄量．在器件基区的少子迁移率、多子迁移率和方块电阻已知的情况下,应用这种方法只需测量室温和液氮温度下的电学特性就可以获得禁带变窄量．这种方法从双极晶体管的集电极电流公式出发,利用VBE做自变量,在室温和液氮温度下测量器件的Gummel图,选取lnIC随VBE变化最为线性的一部分读出VBE及相应的IC数值,获得两条VBE-lnIC直线,通过求解两条直线的交点可以计算出基区的禁带变窄量ΔEG．利用这种方法测试了硅双极器件和锗硅基区双极器件,其基区禁带变窄量分别为41meV和125meV,这个测量结果与文献中的数值符合较好．     

超薄基区SiGe HBT基区渡越时间能量传输模型

通过求解玻尔兹曼能量平衡方程，得出基区的电子温度分布，建立了考虑电子温度变化，适用于超薄基区SiGeHBT的基区渡越时间模型。该模型考虑了电子温度对迁移率的影响，基区重掺杂和Ge引起的禁带变窄效应及速度饱和效应。比较了用能量传模型与漂移扩散模型计算的截止频率，利用器件模拟软件ATLAS进行了模拟，结果与能量传输模型计算结果吻合。     

硅锗基区异质结双极晶体管的研究进展

叙述了硅锗基区异质结双极晶体管的研究发展现状，分析了该晶体管的结构机理、特点及制造技术，并且阐述了该器件的发展前景。     

低温基区轻掺杂硅双极晶体管的温度比例因子设计规则

通过对电流增益温度模型的分析，表明发射区重掺杂引起的禁带变窄效应是低温下双极晶体管电流增益衰变的主要原因，提出了用温度比例因子设计低温基区轻掺杂双极晶体管的新设计方法，计算机模拟表明结果良好。     

低温硅双极晶体管基区优化设计

常规双极晶体管在７７Ｋ下电流增益和频率性能都严重退化。本文首先分析了低温双极晶体管基区Ｇｕｍｍｅｌ数，基区方块电阻，渡越时间和穿通电压等参数与温度及基区掺杂的关系，然后讨论了低温双极器件基区的优化设计问题。     

新型锗硅应变层异质结构双极器件研究进展

新型锗硅材料和器件的发展开创了硅异质结构和能带工程器件的新时代.现代先进的外延技术使应变层锗硅材料的应用成为可能.本文详细评述了新型锗硅应变层异质结构双极器件的研究现状及发展,着重讨论了锗硅应变层的性质和以锗硅应变层作基区的异质结双极器件的性能及其应用前景.     

新型微电子器件及IC

评述了GaAs FET器件以后的新型微电子器件和IC的开发与研究现状,它们包括高电子迁移率晶体管、异质结双极晶体管、硅锗合金基区异质结双极晶体管、真空微电子器件、量子电子器件和光电集成电路.其中,有的已取得可观的实绩,巩固了阵地,有的虽然刚崭露头角,但却显示出雄厚的潜力.它们基本代表了半导体微电子器件未来的发展方向.     

基区重掺杂对SiGe HBT热学性能的影响

相对于同质结晶体管,异质结双极晶体管(HBT)由于异质结的存在,电流增益不再主要由发射区和基区掺杂浓度比来决定,因此可以通过增加基区掺杂浓度来降低基区电阻,提高频率响应,降低噪声系数,但基区掺杂浓度对器件热特性影响的研究却很少。以多指SiGeHBT的热电反馈模型为基础,利用自洽迭代法分析了基区重掺杂对器件集电极电流密度和发射极指温度的影响。通过研究发现,随着基区浓度的增加,SiGe HBT将发生禁带宽度变窄,基区反向注入发射区的空穴电流增大;同时,基区少子俄歇复合增强,这些都将减小集电极电流密度,降低发射极指温度,从而抑制发射极指热电正反馈,提高器件的热稳定性。     

Si-Ge异质结基区混合模式晶体管的提出和模拟

在常规混合模式晶体管的基础上提出一种新结构的器件—— Si- Ge异质结基区混合模式晶体管。由于基区采用禁带宽度较窄的 Si- Ge合金材料 ,引起空穴向发射区反注入势垒的提高 ,使 IB空穴电流减小 ,从而提高了注入效率 ;迁移率增高 ,从而提高特征频率。因而这种器件具有 β高、基区电阻低、基区渡越时间短等优点。通过器件模拟证实了该器件具有输出电流大、低温放大倍数极高、常温放大倍数较高、特征频率高等优点 ,是下一代 IC的发展方向     

新的高性能硅锗异质器件结构

本文介绍硅锗技术在提高器件和电路性能方面的新发展,包括用于提高器件速度和低温下应用的硅锗异质结双极晶体管(HBT),以及用于提高PMOS管空穴迁移率的硅锗异质结构.     

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.     

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.     

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.     

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.     

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.     

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.     

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