直拉硅单晶放肩过程的有限元数值模拟与控制参数研究  

Finite Element Numerical Simulation and Control Parameter of Czochralski Silicon Monocrystal during Shoulder Growth Process

作　　者：张晶[1] 刘丁[1] 赵跃[1] 焦尚彬[1] 

机构地区：[1]西安理工大学自动化与信息工程学院,西安710048

出　　处：《人工晶体学报》2013年第1期58-64,共7页Journal of Synthetic Crystals

基　　金：国家科技重大专项(2009ZX02011001);教育部科学技术研究重点项目资助项目(212169)

摘　　要：放肩是直拉法生长硅单晶保持无位错生长的过程,是晶体能够顺利进入等径生长的关键。生产实践中发现,在放肩前段经常出现液流线切入晶体随之变晶的现象。本文提出了放肩前期的变晶转拉晶工艺,采用有限元数值模拟的方法计算出熔体热对流及温度分布,给出了固液界面附近熔体中的流速变化规律,解释了液流线的成因,通过仿真结果和拉晶实验结果表明该方法的有效性。Both formation of a dislocation free crystal nucleus and abilitity to entrance to body growth during crowning growth are cruxes of Cz-Si monocrystal growth. It often shows dislocation happened after an unknown flow on melt surface cutting in crystal in the process of crowning growth in practice. In the paper, crystal rotation process is proposed at the beginning of crowning growth. Melt convection and temperature distribution are calculated by finite element numerical simulation. Flow rate variation near the solid-liquid interface melt surface and explanation the formation of the flow are given. Simulation and experiment results show the effectiveness for the proposed method.

关 键 词：直拉硅单晶 放肩 晶转 有限元数值模拟 

分 类 号：O78[理学—晶体学]