Structural and electrical properties of undoped GaAs grown by MOCVD

Abstract

The present paper describes the results from the growth of undoped epitaxial GaAs by low pressure Metal Organic Chemical Vapor Deposition (MOCVD) and its structural and electrical properties. The growth temperature and pressure were 700/spl deg/C and 100 Torr, respectively. Growth was carried out at different V/III ratios and hydrogen flow rates. Epilayers thus grown were shown to have uniform thickness, smooth surface, crystalline structure, stoichiometric and low background impurity concentration. The increasing V/III ratio resulted in the p-to n-type transformation of the epilayers. With increasing hydrogen flow rate, the background carrier concentration was decreased. Hall mobility of 90,000 cm/sup 2/ V/sup -1/ s/sup -1/ at 77 K for a carrier concentration of 1/spl times/10/sup 15/ cm/sup -3/ was obtained.