摘要
本文以开发长波长半导体光电子材料为目的，对ＧａＡｓ１－ｘＳｂｘ／ＧａＡｓ这一大失配异质结材料开展了较为深人的研究，利用国产ＭＢＥＩＩＩ型设备外延生长了全组分的ＧａＡｓ１－ｘＳｂｘ材料，化学热力学数据分析表明，Ｓｂ结合到ＧａＡｓｓｂ中的速率比Ａｓ高得多，实验表明，合金组分可由Ｓｂ／Ｇａ束流比控制，也发现Ｓｂ束流的支配作用随温度升高而降低．利用ＴＥＭ和ＲＢＳ技术研究了异质结界面及外延层的晶体质量，实验表明采用组分阶变的过渡层有效地抑制了界面位错向体层的延伸，可以获得较高晶体质量的外延层．
Abstract For the target of developing long wave length optoelectronic material,some investigation on GaAs1-xSbx/GaAs-a very large lattice-mismatch heterostructure have been proceeded. A series of GaAs1-.xSbx in different x value has been successfully grown by using homemade type-Ⅲ MBE system. According to the chemical thermodynamic data of GaAs and GaSb, the combination rate of Sb in GaAsSb is much higher than As. Through a large amount of experments, we discovered that the x value can be controlled by flux ratio of Sb/Ga, and the dominance of Sb flux will be decreased when the growth temperature increased. The epilayer and interface have been checked by TEM and RBS technology. The results suggest that the composition step-changed buffer layer comfines the misfit dislocations in the in terface effectively, and even high quality epilayers can be obtained.
