半绝缘砷化镓单晶中碳微区分布的研究

通过AB腐蚀（由Abrahams和Buiocchi发明的腐蚀方法，简称AB腐蚀）、KOH腐蚀，经金相显微镜观察、透射电子显微镜能谱分析、电子探针x射线微区分析，对液封直拉法生长的非掺 半绝缘砷化镓单晶中碳的微区分布进行了分析研究.实验结果表明，碳的微区分布受单晶中 高密度位错网络结构的影响.高密度位错区，位错形成较小的胞状结构，且胞内不存在孤立 位错，碳在单个胞内呈U型分布；较低密度位错区，胞状结构直径较大，且胞内存在孤立位 错，碳在单个胞内呈W型分布. 关键词： 半绝缘砷化镓 胞状位错 碳受主

Micro-distribution of carbon in semi-insulating gallium arsenide

Micro-distribution of C acceptor defect in semi-insulating gallium arsenide (SI-GaAs) wafer has been investigated by means of chemical etching, microscopic observation, transmission electron microscope, eelectron probe x-ray microanalyz er.Experimental results show that there is a corresponding relationship between the distribution of C impurity and dislocation density in a wafer. In relatively high dislocation density areas, dislocations form relatively small cells with few isolated dislocation within each cell. Here the profile of C distribution in the area of a cell is “U”-shaped. The cell diameter increases as the dislocation density decreases, and the dislocations form relatively large cells with a few isolated dislocations within each cell. The profiles of C distributio n in the area of a cell is “W”-shaped.