Diffusion of both Ga and Bi into InSb seeds during growth of InGaSbBi

摘要

In1minus;xGaxSb1minus;yBiy(0xle;0.21, 0yle;0.005) quaternary bulk single crystals were grown on InSb seed crystals using a rotary Bridgman method. In order to investigate the quality of these crystals, various kinds of measurements were carried out, such as optical microscope, xhyphen;ray topograph, fourhyphen;crystal xhyphen;ray diffractometry, electronhyphen;probe microanalysis, energyhyphen;dispersive spectroscopy, and secondaryhyphen;ionhyphen;mass spectroscopy. All grown crystals were 10 mm in diameter and more than 10 mm in length. This indicates that the rotary Bridgman method was useful to grow quaternary bulk single crystals. Owing to segregation, the compositional ratio of Bi (y) increased and that of Ga (x) decreased as crystals grew. During growth of InGaSbBi, both Ga and Bi diffused into the InSb seed and there appeared domains of InBi. For comparison, InSb1minus;yBiy(0yle;0.05) and In1minus;xGaxSb (0xle;0.16) were grown on InSb. It turned out that Bi did not diffuse into InSb without Ga, but Ga diffused without Bi. The incorporation of Ga produced the excess In and as a result InBi domains were formed.