Light - voltage conversion type semiconductor light receiving element, optical signal processing device and an optical integrated device

摘要

PROBLEM TO BE SOLVED: To realize a semiconductor photo detecting element of high speed and efficiency which needs no external power source. SOLUTION: A doping dipole structure constituted of an N-type high density delta doped layer 132 and a P-type high density delta doped layer 131 which are adjacent to each other at most 20 nm is periodically formed in an undoped layer 133 which is to be irradiated with a light, thereby turning the band structure of a light absorbing layer into a sawtooth type. When the undoped layer 133 is irradiated with a light, a photo carrier is drifted by the sawtooth type band structure, collected in the doping dipole structure region, and a large electromotive force is generated by direct recombination and indirect recombination. As the result, high response and high efficiency can be made compatible with each other, so that a semiconductor photo detecting element which generates a signal voltage in the element and needs no external power source can be provided. An optical integrated element in which a semiconductor photo detecting element is arranged on the same substrate, and an optical communication and measuring device mounting the elements can be obtained.