PHOTODETECTORS WITH LIGHT INCIDENT SURFACE AND CONTACT SURFACE AND APPLICATIONS THEREOF

摘要

The disclosed invention relates to structures and fabrication methods of photodetectors based on photodiodes for various applications using 3D integration approach. The structure of the photodetector comprises at least two layers (202, 203) bonded to each other, wherein a first layer (202) is made of a semiconductor material having a first conductivity type and a first concentration. A second layer (203) is made of a semiconductor material which is either in direct contact with the first layer (202) or bonded to the first layer by a bonding layer (216) made of a thin dielectric material. At least one region (206) of second conductivity type, at least a p/n junction and at least one region (207) of the first conductivity type with a second concentration heavier than the first concentration is formed within the first layer (202). A through silicon via (211, 214) is formed in the second layer (203). The at least one region (206) of the second conductivity type detects light photons scattered from along a reference path that traverses a reference region (220, 221) which defines a reference point within the first layer (202) of the structure for aligning the impinging light and comprises a part of the photodetector for a particle sizing application.