INCORPORATION AND ACTIVATION OF FE IN INP USING LOW-PRESSURE MOCVD

The incorporation and activation of Fe in InP has been studied using ferrocene as a dopant source in low pressure MOCVD, An iron activation energy of 0.9 eV is found with no dependence of the total Fe concentration on PH3 flow, which is contrary to previous results for growth of Fe doped InP at atmospheric pressure. The results for low pressure growth are interpreted in terms of the formation of a single phosphorus vacancy-Fe complex on the surface of the growing layer as Fe is incorporated. A linear relationship between Fe incorporation and total reactor pressure at fixed inlet gas flows was also found, which is explained in terms of a rate limiting Fe incorporation reaction on the InP surface. This result is contrary to the predictions of a mass transport limited flux of ferrocene to the growth interface. The activation of Fe in InP at or below the solubility limit was found to increase as the PH3 concentration in the reactor decreased.