Undoped semi‐insulating GaAs grown by a vertical Bridgman method: Electrical property analysis using a simple ambipolar correction

A simple procedure is described for numerical correction of conductivity and Hall‐effect data in a (GaAs) sample which is near intrinsic or slightly on the n side of intrinsic, such that hole conduction affects the conductivity and Hall coefficient to a modest extent. The numerical procedure is based on the ratio of the measured Hall coefficient to that expected for intrinsic GaAs at the same temperature. One can thereby deduce the electron concentration n0 and the electron mobility, simply, but with reasonable accuracy. The method can be used for any temperature at which transport measurement are normally made with semi‐insulating GaAs, and its use is demonstrated with data for three high‐resistivity ‘‘undoped’’ samples from crystals grown by a vertical Bridgman method.