VARIABLE RANGE PHOTODETECTOR WITH ENHANCED HIGH PHOTON ENERGY RESPONSE AND METHOD THEREOF

摘要

A photodiode comprising a substrate; first semiconducting region; first contact; second region comprising an absorption region for the photons having a predetermined energy range; the second region being formed of a semiconductor having a high surface or interface recombination velocity; a third semiconducting region transparent at the predetermined photon energy range suitable for making an operative connection to a second contact; the second and third regions forming a second interface; the first and second regions forming a first interface; the second region being configured such that biasing the photodiode results in depletion of the second region from the first interface to the second interface or at least one of the absorption depth and the sum of the absorption depth and diffusion length from the second interface; the depletion resulting in the creation of an electric field whereby photogenerated carriers are collected by drift and a method of making the foregoing.

主权项

1. A method of making a photodiode which eliminates or minimizes surface recombination of photogenerated carriers generated by photons having a predetermined energy range comprising:
providing a substrate; providing a first semiconducting region operatively associated with the substrate suitable for forming a contact thereon; providing a first contact operatively associated with the first semiconducting region; providing a second region comprising an absorption region for the photons having a predetermined energy range; the second region being formed of a semiconductor having a high surface or interface recombination velocity; providing a third semiconducting region transparent at the predetermined photon energy range suitable for making an operative connection to a second contact; providing a second interface between the second and third regions upon which the photons impinge;the first semiconductor region and the second region forming a first interface such that the second region is depleted at the reverse bias point of operation; the depletion width in the second region varying with applied reverse bias; the minimal depletion width extending from the first interface to at least the sum of the absorption depth and the effective diffusion length from the second interface; the photodiode being configured such that biasing the photodiode results in depletion of the second region;whereby the depletion results in the creation of an electric field and photogenerated carriers are collected by drift.