Impact Ionization and Charge Transport in GaAs: GaP 50% Alloy

摘要

Diodes of 50% alloy of GaAs: GaP have been studied in which the material has been made semi‐insulating by compensation with iron. An electrode of evaporated gold on this material is blocking for electrons. Electrons may be injected from a base wafer of n‐type GaAs. The material is slightly p‐type due to ionization of deep acceptor levels. When electrons are injected there is a space‐charge‐limited current in which the electron concentration is controlled by a small concentration of holes which are present. Analysis of the data gives estimates of the concentration and capture cross section for recombination centers. Using a blocking contact, impact ionization multiplication of carriers injected by light is observed. The impact ionization coefficient is measured.