Photo Sensor

Abstract

A photo sensor has an insulator layer for covering a diode stack, and the insulator layer is made of photoresist to reduce a side leakage current.

1 . A photo sensor having at least one switching element region and an electronic element region on a substrate, wherein the photo sensor comprises:
 a gate disposed on the switching element region of the substrate;   a gate dielectric layer covering the gate and the substrate;   a channel region disposed on the gate dielectric layer above the gate;   a source/drain disposed on the opposite sides of the channel region and covering the gate dielectric layer underneath the opposite sides of the channel region;   a diode stack disposed on at least one of the source/drain in the electronic element region;   a photoelectrode disposed on the diode stack;   a insulating layer covering the source/drain, the channel region, the diode stack and the photoelectrode, and having a opening to expose a part of the photoelectrode on the diode stack, wherein the material of the insulating layer is a photoresist; and   a bias electrode disposed on a part of the insulating layer on the source/drain and connecting to one side of the photoelectrode near the source/drain along the opening.   
   
   
       2 . The photo sensor of  claim 1 , wherein the photoresist is resin type black matrix photoresist. 
   
   
       3 . The photo sensor of  claim 1 , wherein the photoresist is phenolic resin, epoxy resin, or acrylic resin. 
   
   
       4 . The photo sensor of  claim 1 , wherein the thickness of the insulating layer is at least 0.5 μm. 
   
   
       5 . The photo sensor of  claim 1 , wherein the thickness of the insulating layer is 0.5-1.6 μm. 
   
   
       6 . The photo sensor of  claim 1 , further comprising a protective layer disposed on the bias electrode and the insulating layer of the electronic element region, and having a lighting opening to expose a part of the photoelectrode. 
   
   
       7 . The photo sensor of  claim 1 , wherein the channel region comprises:
 a semiconductor layer; and   an electrical property enhancement layer disposed on both sides of the semiconductor layer.   
   
   
       8 . The photo sensor of  claim 7 , wherein the electrical property enhancement layer is an n-doped silicon layer. 
   
   
       9 . The photo sensor of  claim 1 , wherein the diode stack comprises a first doping layer, an intrinsic semiconductor layer, and a second doping layer. 
   
   
       10 . The photo sensor of  claim 9 , wherein the first doping layer is an n-doped silicon layer and the second doping layer is a p-doped silicon layer. 
   
   
       11 . The photo sensor of  claim 9 , wherein the intrinsic semiconductor layer is an amorphous silicon layer.