Selective embedded growth by LP-MOVPE in the Ga-In-As-P system

Abstract We have investigated the selective embedded growth by LP-MOVPE (low pressure metalorganic vapor phase epitaxy) of InP and GaInAs (on InP) and of GaAs and GaInP (on GaAs) in grooves with (011), (111)A and (111)B side wall facets prepared by wet chemical etching and reactive ion etching of (100) substrates. For all materials studied a reduction of the growth rates on the side walls compared to those on the bottom was observed. This reduction is enhanced by surface migration of nutrients from side wall facets to the bottom of the groove. The deposition rate is also affected by the geometry of the trenches. For narrow lines this results in a drastically reduced rate compared to that in wider trenches. Additionally, the composition of the selectively grown ternaries GaInAs and GaInP is different from that in large area growth and depends further on the size of the grooves. Based on the insights gained in this study grooves, refilled with GaInAs/InP or GaInP/GaAs multilayers with planar surfaces, could be realized. In contrast to the growth of GaInP on GaAs and of InP on InP, the deposition of the arsenic-containing III–V compounds on the side wall facets of the grooves can be successfully suppressed.