Patent ID: 9419155
Filing Date: 2016-08-16
CPC Classification: H01L

Claim Text:
1. A method of making a semiconductor device, the method comprising: forming at least one radiation sensing element in a second epi-layer of an intermediate product, wherein the intermediate product comprises a substrate, a first epi-layer over the substrate and the second epi-layer over the first epi-layer, wherein the second epi-layer has a different composition from the first epi-layer, and the second epi-layer has a doped surface extending across the entire second epi-layer in a direction parallel to an interface between the first epi-layer and the substrate; forming an interconnect layer over the second epi-layer of the intermediate product to electrically connect with the at least one radiation sensing element; and removing the substrate and the entire first epi-layer to expose the entire doped surface of the second epi-layer.