LIGHT RECEIVING ELEMENT AND LIGHT RECEIVING DEVICE INCORPORATING CIRCUIT AND OPTICAL DISC DRIVE

摘要

A light receiving element comprising a P type diffusion layer (101), a P type semiconductor layer (102), an N type diffusion layer (103) becoming a light receiving part, and a light transmitting film (104), all formed on a P type silicon substrate (100). The N type diffusion layer (103) has a thickness of 0.8−1.0 μm which is larger than the absorption length of incident light having wavelength of 400 nm, and such a concentration profile that the impurity concentration is not higher than 1E19 cm−3 on the surface and has a peak in the vicinity of the surface. Since recombination of carriers generated by the incident light is prevented in the vicinity of the surface of the N type diffusion layer (103), sensitivity of the light receiving element is enhanced and response speed is enhanced by the low−resistance N type diffusion layer (103) having a large junction depth.