“…In the literature basically two compounds have been proposed to be the interlayer alloy, i.e., In x Ga 1−x As [8,14,18,19] and In x Ga 1−x As 1−y P y [7,8,10,13,20,21]. The formation of either one of these two compounds has been reported to be strongly affected by the growth conditions, such as growth interruption or not, duration of the PH 3 purge after stopping the growth of InGaP, duration of the As H 3 pre-flow before TMGa is introduced, intentional interposition of some extra layer etc [7,8,10,13,14,[18][19][20][21].…”