Si-Al电子封装材料粉末冶金制备工艺研究

采用粉末冶金液相烧结工艺制备了Si-50％Al（质量分数)电子封装材料。研究了压制压力、烧结工艺对材料微观组织及性能的影响。结果发现：低温烧结时，随压制压力增大，材料密度呈上升趋势，而高温烧结时，材料密度较高且变化不大；增大压制压力不仅提高了材料的致密度，而且改善了界面接触方式，在一定范围内使得材料热导率提高，但压制压力过大时，则会导致Si粉出现大量的微裂纹等缺陷，界面热阻急剧上升，从而降低热导性能；适当提高烧结温度和延长烧结时间可以提高材料的热导率。     

Effects of Solid-State Reaction Synthesis Processing Parameters on Thermoelectric Properties of MgaSi

The Mg2 Si-matrix thermoelectric material was stnthesized by low temperature solid-state renc-tion.This paper studies the effects of holding time and reaction temperatare on the particle size and the properties of the material, and also studies effects of doping elemental Sb, Te and their doping seqence on the properties of the materiol. The result shows that excessirely high temperature and elongated holding time of solid-state reaction are harmful, there is a range of partiele size to ensure optimum properties and the doping sequence of Sb or Te without influencing the properties.     

Investigation of SiGe-on-Insulator Novel Structure

SiGe-on-Insulator (SGOI) is an ideal substrate material for realizing strained-silicon structures that are very competing and popular in present silicon technology. In this paper, two methods are proposed to fabricate SGOI novel structure. One is modified Separation by Implantation of Oxygen (SIMOX) starting from pseuodomorphic SiGe thin film without graded SiGe buffer layer. Results show that two-step annealing can improve the cystallinity quality of SiGe and block the Ge diffusion in high temperature annealing. SGOI structure with good quality has been obtained through two-step annealing. The second method is proposed to achieve SGOI with high content of Ge. High quality strained relax SiGe is grown on a compliant silicon-on-insulator (SOI) substrate by UHCVD firstly. During high temperature oxidation,Ge atoms diffuse into the top Si layer of SOI. We successfully obtain SGOI with the Ge content of 38%, which is available for the growth of strained Si.     

Photoreflectance Spectroscopy for Study of Si/SiGe/Si Heterostructure

UHVCVD-grown Si/Si1- xGex/Si heterostructure was investigated by Photoreflectance spectroscopy (PR). The principle of PR used in semiconductor film was thoroughly described. According to the E1 transition energy in the Si1- xGex alloy, the Ge content in SiGe film with constant composition can be accurately characterized. In this study, determine the composition uniformity of larger diameter SiGe epiwafer by PR mapping technique was determined. These results show PR is very promising for Si1- xGex epilayer characterization with constant Ge content and can provide film measurements for production-worthy line monitor.     

Influence of Si on Interfacial Combination of SiCp/Al-Mg-Si Composite

The scanning electron microscopy (SEM) analysis results of Si distribution in the interface between SiC reinforcements and aluminum matrix of a stir casting SiCp/Al-Mg-Si composite were presented. Results show that there is Si precipitation deposit on the interface of the composite and Si connects with SiC reinforcements in one side and connects with aluminum matrix in the other side. Si phase plays as a connecting bridge, which contributes to the interfacial combination of SiCp/Al composite.     

Comparison of a‐Si and Poly‐Si for AMOLED displays

Abstract— The characteristics of OLED backplanes including the intrinsic properties of a‐Si TFTs and LTPS TFTs will be reviewed. While LTPS TFTs reveal satisfactory stability in AMOLED‐display applications, a‐Si AMOLEDs show better uniformity and are capable of driving OLEDs. However, the stability of a‐Si TFTs under long‐term operation is still unacceptable and remains to be the key issue constraining the commercialization of a‐Si TFT AMOLEDs.     

基于模糊控制系统的高炉铁水硅含量预报的研究

运用模糊控制理论建立了高炉铁水w(Si)的模糊控制预报模型,用某厂实际生产数据进行仿真检验得到了较好的预报效果。     

Fe-Ni-Si基奥氏体时效合金的马氏体相变和形状记忆效应

It is well known that the morphologies of the α martensite formed from the γ phase in ferrous alloys are classified into five types of lath, butterfly, (225)A type plate,lenticular and thin-plate. Among those α martensites, onlythe thinplate martensite, which is characterized by containing a high density of transformation twins, has a potential of exhibiting a perfect shape memory (SM) effect.Recently the present authors found in Fe-Ni-Si alloys that the thin-plate martensite is formed by the introduction of fine and coherent γ-(Ni,Fe)3Si particles with a L12 ordered structure in the austenite matrix due to ausaging. In the present study, the SM properties of the ausaged Fe-Ni-Si alloys with the thin-plate martensite are investigated by a conventional bending-test. The effects of the addition of Co to the Fe-Ni-Si alloys on the martensitic transformation and the SM properties are also investigated. It is shown that while the ausaged Fe-Ni-Si ternary alloys exhibit an imperfect SM effect due to reverse transformation from stress-induced thin-plate martensite to austenite, the SM properties are improved by the addition of Co. An almost perfect SM effect is confirmed in the Fe-Ni-Si-Co alloys by heating to 1 100 ℃ after deformation at -196 ℃.     

基于高温抗辐照SOI CMOS工艺的器件特性研究

绝缘体上硅（SOI）技术因其独特的优势而广泛应用于辐射和高温环境中,研究不同顶层硅膜厚度（tSi）的器件特性,对进一步提升高温抗辐照SOI CMOS器件的性能至关重要。本工作首先通过工艺级仿真构建了N沟道金属氧化物半导体场效应晶体管（NMOSFET）的模型,并对其进行了分析,基于仿真结果,采用015 μm抗辐照SOI CMOS工艺制备出具有不同硅膜厚度的实际器件,该工艺针对高温应用引入了设计与材料的优化。结果表明,薄硅膜和厚硅膜NMOSFET在150 krad(Si) 总剂量辐射下表现出相近的抗辐照加固性能,而前者在225 ℃高温下具有较小的漏电流,因此具有较薄硅膜的NMOSFET更适用于高温电子器件的制造。