Effects of Growth Parameters on Oxygen Incorporation into InGaAlP Grown by Metalorganic Chemical Vapor Deposition

Abstract
Oxygen incorporation into In0.5(Ga1-x Al x )0.5P grown by metalorganic chemical vapor deposition has been quantitatively investigated as a function of growth parameters. The oxygen concentration (N O) increased with increasing Al composition (x). Marked decreases in N O for x=0.7 and 1.0 were observed as the V/III ratio (molar flow rate ratio of group-V to group-III sources) was increased, although N O for x=0.7 was almost independent of the substrate temperature (T S). Since N O for x=1.0 was strongly affected by the amount of oxygen-containing species in trimethylaluminum (TMA), the origin of oxygen in InGaAlP is thought to be TMA. Net acceptor concentration (N A-N D) in Zn-doped InGaAlP for x=0.7 and 1.0 decreased with increasing N O. Oxygen may act as a deep donor, compensating for Zn acceptors.