Improvements in GaAs/plasma‐deposited silicon nitride interface quality by predeposition GaAs surface treatment and postdeposition annealing

Substantial improvements in the electrical properties of interfaces between n‐type GaAs and Si3N4 formed by plasma‐enhanced CVD have been obtained by in situ substrate surface treatment with a hydrogen plasma and postdeposition annealing. For samples with surface treatment and deposition performed at 300 °C, annealing at 600° for 30 min in N2 produced a dramatic reduction of capacitance frequency dispersion. Capacitance and conductance data indicate a major reduction of surface state density. Low‐frequency C–V on an illuminated sample show evidence of surface inversion. AES composition profiles are presented as evidence that the hydrogen plasma treatment reduces native oxide on the GaAs.