日本研究人员用 SEM 与 TEM 详细研究了低压OMVPE 法 GaAs 外延层的表面缺陷。外延层生长以GaAs 为基底,方向(100)±0.5°,生长温度630～650℃,Ⅴ/Ⅲ约20～100,生长压力0.1～76Torr 文章用 SEM 与 TEM 详细观测了表面缺陷的形状和内部构造。研究发现,低压 OMVPE 法 GaAs 外延层表面分布着从表面凸起的椭圆锥形缺陷,与氯化物 VPE 法GaAs 外延层表面的小丘类似。而且,在每个缺陷中心附近存在一个位错。这一现象表明,具有旋转成分的位错终端的缧旋生长导致了椭圆锥形表面缺陷的形 Japanese researchers used SEM and TEM to investigate the surface defects of low-voltage OMVPE GaAs epitaxial layers. The epitaxial layer grows on the GaAs substrate with the direction of (100) ± 0.5 °, the growth temperature of 630 ~ 650 ℃, the V / Ⅲ of about 20 ~ 100 and the growth pressure of 0.1 ~ 76 Torr. structure. It is found that the elliptical pyramidal defects protruding from the surface are distributed on the surface of low-pressure OMVPE GaAs epitaxial layer, which is similar to the surface of the hill in GaAs epilayer of VPE method. Also, there is a dislocation near each defect center. This phenomenon shows that the spin-on growth of the dislocation terminal with the rotational component causes the shape of an elliptical conical surface defect