Electrochemical Capacitance-Voltage (EC-V) of AlGaAs: C Growth by Metalorganic Chemical Vapor Deposition (MOCVD) for Atomic Interdiffusion

Abstract

Electrochemical capacitance-voltage (EC-V) method has been used to investigate the effect of carbon tetrachloride to AlGaAs layer. The AlGaAs layers doped with carbon were grown using metalorganic chemical vapor deposition (MOCVD) at temperature growth of 650^oC. Electrochemical capacitance-voltage (EC-V) has been used to measure the etchback (the growth rate) AlGaAs layer. Scanning electron microscopy (SEM) was also used to confirm the EC-V results to measure the thickness of the AlGaAs:C layers. The samples were grown at various temperatures and CCl₄ flow rate on (001) oriented p-GaAs. Based on the EC-V measurement, it was found that the etchback was strongly dependent on growth temperature and CCl₄ flow rates. In comparison to the previous results of GaAs:C superlattices, the hole concentration in AlGaAs:C was much higher than in GaAs:C at the same growth condition (growth temperature = 700^oC, CCl₄ flow = 0.89 µmol/min) with the etchback rate in AlGaAs:C slower than in GaAs:C.