Patent ID: 9147776
Filing Date: 2015-09-29
Classification: H01L

Abstract:
1. An image sensor pixel, comprising: a photodiode region having a first polarity doping type disposed in a semiconductor layer; a pinning surface layer having a second polarity doping type disposed over the photodiode region in the semiconductor layer, wherein the second polarity is opposite from the first polarity; a first polarity charge layer disposed proximate to the pinning surface layer over the photodiode region; a contact etch stop layer disposed over the photodiode region proximate to the first polarity charge layer, wherein the first polarity charge layer is disposed between the pinning surface layer and the contact etch stop layer such that first polarity charge layer cancels out charge having a second polarity that is induced in the contact etch stop layer; a metal stack layer that includes a plurality of metal interconnects disposed directly over the contact etch stop layer to provide electrical connections; and a passivation layer disposed over the photodiode region between the pinning surface layer and the contact etch stop layer, wherein the passivation layer is disposed over the photodiode region between the pinning surface layer and the first polarity charge layer.