Noise characteristics of GaAs-AlGaAs heterojunction punch-through phototransistors

Novel GaAs-AlGaAs heterojunction phototransistors with a /spl delta/-doped base have been fabricated. Very high gain and low output noise have been measured. The measured noise is composed of shot noise associated with collector quiescent bias current and amplified shot noise due to collector leak current for nonpassivated devices. The high gain and low intrinsic noise characteristics of these transistors make them very promising in weak light detection.