Patent ID: 9024359
Filing Date: 2015-05-05
Classification: H01L,Y02E

Abstract:
1. A photodetector comprising: a photo absorbing layer having a predetermined doping type, a contact layer having the predetermined doping type, and a barrier layer disposed between said photo absorbing and contact layers, said barrier layer being configured to prevent majority carrier transport; where the barrier layer is graded with a first grading at a first interface area between said barrier layer and said contact layer and graded with a second grading at a second interface area between said barrier layer and said photo absorbing layer such that the first grading creates a graded transition from the minority carrier band edge of the barrier layer to the minority carrier band edge of the contact layer; and the second grading creates a graded transition from the minority carrier band edge of the photo absorbing layer to the minority carrier band edge of the barrier layer.