Wide dynamic range Photodetector using Field Emitters

Abstract

The back illumination type photosensitive field emitter was fabricated by depositing p-type a-SiC : H/intrinsic a-Si : H photodiode on the back surface of non-gated n-type cone-shaped Si emitters by using plasma CVD methode. The emission current correspnding with illumination intensity was observed and the quantum efficiency of about 0.7 was obtained at λ=680nm. However, the emission current has tendency to be saturated at high illumination level. To expand the dynamic range of the photodetector, the photosensitive field emitter composed of gated field emitter and p-type a-SiC : H/intrinsic a-Si : H photodiode film was demonstrated.