直拉硅单晶原生漩涡缺陷的研究

本文用化学腐蚀方法,从含有漩涡缺陷的原生CZ硅单晶中分离出尺寸在1000—6000?间的氧沉淀,制成萃取复型样品,用TEM对氧沉淀作微区电子衍射分析。同时,观察硅薄膜中漩涡缺陷的TEM象,确定了二者的对应关系。结果表明,构成漩涡缺陷的氧沉淀主要是呈方形片的热液石英(keatite,silicak)及少量呈六角片的α方英石(α-cristobalite),沉淀片周边沿<110>方向,惯习面前者的为{100},后者的为{111}。样品的红外吸收光谱表明,方片状热液石英沉淀可能与1224cm^-1吸收峰相对应。 关键词：

A STUDY ON AS-GROWN SWIRL DEFECTS IN CZ SILICON CRYSTAL

The oxide precipitates (1000-6000 ?) were separated from as-grown CZ silicon crystal containing the swirl defects by means of chemical etching method. The selected-area electron diffraction analysis of the precipitates, which had been prepareted into the extraction replica specimens, was carred out in TEM. Simultaneously, the morphology of the swirl defects in silicon thin foil specimens was observed with TEM. Thereby, the corresponding relation between the particles in the extraction replicas and the swirl defects in the silicon thin foils was established. It was concluded that a great number of the swirl defects are keatite (silica k) in the form of sguare-shaped platelets with {100} habit planes and sides in parallel with 〈ll0〉 direction, and a small part of the swirl defects are a-cristobalite in the form of hexagon-shaped platelets with {111} habit planes and sides in parallel with 〈ll0〉. IR absorption spectra of as-grown CZ silicon samples showed that the square plate-shaped keatite were probably associated with the absorptior band at 1224cm^-1.
Keywords：