硅/硅键合新方法的研究

研究成功用Ⅳ族元素锗进行硅／硅键合的一整套新技术（代替通用的亲水法）;实现了键合层无孔洞,边沿键全率达９８％以上,键合强度达２１５６Ｐａ以上,并通过在锗中掺入与低阻同型号的杂质,实现了应力补偿。     

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.     

用Si—Fe,Si—Al升温钢液的研究

在硅化钼电阻炉和中频感应炉内，用Ｓｉ－Ｆｅ、Ｓｉ－Ａｌ合金作发热剂进行了钢液升温的实验研究。在感应炉的实验条件下，加Ｓｉ－Ｆｅ时升温速度为４．８℃·ｍｉｎ－１，升温值１４．６℃；加Ｓｉ－Ａｌ时升温速度为８．６℃·ｍｉｎ－１，升温值２５．９℃。研究了发热剂过剩指数、供氧速度、氩气流量对升温速度、升温值的影响。在实验的基础上，对化学升热法涉及的工艺理论问题，如发热剂中发热元素的含量、底吹氩搅拌的作用、升温过程中钢中元素含量的变化进行了探讨     

Modification of Primary Mg2Si in Mg-4Si Alloys with Antimony

The refinement in size and modification in morphology for primary Mg₂Si depended significantly on Sb contents in Mg-4Si alloys. Adding Sb into melts evidently increased the nucleus numbers of primary Mg₂Si crystals. Moreover, the preferential growth along $ \left\langle { 100} \right\rangle $ directions in dendritic crystals was restricted greatly due to the Si sites being substituted by Sb in Mg₂Si lattices, resulting in modified primary Mg₂Si crystals growing to octahedral morphology surrounded by {111} planes; therefore, the modification process could be called adsorption and poisoning mechanisms.     

Refinement of Eutectic Si Phase in Al-5Si Alloys with Yb Additions

A series of Al-5 wt pct Si alloys with Yb additions (up to 6100 ppm) have been investigated using thermal analysis and multiscale microstructure characterization techniques. The addition of Yb was found to cause no modification effect to a fibrous morphology involving Si twinning; however, a refined plate-like eutectic structure was observed. The Al₂Si₂Yb phase was observed with Yb addition level of more than 1000 ppm. Within the eutectic Al and Si phases, the Al₂Si₂Yb phase was also found as a precipitation from the remained liquid. No Yb was detected in the α-Al matrix or plate-like Si particle, even with Yb addition up to 6100 ppm. The absence of Yb inside the eutectic Si particle may partly explain why no significant Si twinning was observed along {111}_Si planes in the eutectic Si particle. In addition, the formation of the thermodynamic stable YbP phases is also proposed to deteriorate the potency of AlP phase in Al alloys. This investigation highlights to distinguish the modification associated with the ever present P in Al alloys. We define modification as a transition from faceted to fibrous morphology, while a reduction of the Si size is termed refinement.