Sublattice Rotation of GaP Grown on 2°-Misoriented Si Substrate Using Metalorganic Vapor Phase Epitaxy

Abstract

GaP was grown on 2°- or 4°-misoriented Si substrates at 800 or 830 °C using metalorganic vapor phase epitaxy. Single-domain GaP layers were obtained on the 4°-misoriented substrates at both temperatures. Atomic force microscopy (AFM) revealed that the GaP surface feature was perpendicular to the misorientation direction. A single-domain GaP layer was achieved on the 2°-misoriented substrate only at 800 °C. The GaP surface feature on the 2°-misoriented substrate rotated 90° with respect to that on the 4°-misoriented substrate, which indicates sublattice rotation. AFM revealed that domains elongating along the misorientation direction were found more in the initial growth stage on the 2°-misoriented substrate at 800 °C than on the 4°-misoriented substrate. The Si surface with double domains is responsible for the sublattice rotation. Transmission electron microscopy observation showed neither stacking faults nor threading dislocations in the GaP layer grown on the 2°-misoriented substrate at 800 °C.