EFFECTS OF GROWTH-PARAMETERS ON OXYGEN INCORPORATION INTO INGAALP GROWN BY METALORGANIC CHEMICAL VAPOR-DEPOSITION

Oxygen incorporation into In0.5(Ga1-xAlx)0.5P grown by metalorganic chemical vapor deposition has been quantitatively investigated as a function of growth parameters. The oxygen concentration (No) 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 No 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 (NA-ND) 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.