Solid-state imaging device, method of manufacturing the same, and electronic apparatus

Abstract

A solid-state imaging device includes an Si substrate in which a photoelectric conversion unit that photoelectrically converts visible light incident from a back surface side is formed, and a lower substrate provided under the Si substrate and configured to photoelectrically convert infrared light incident from the back surface side.

What is claimed is: 
     
         1 . An imaging device comprising;
 a first substrate configured to absorb at least a portion of visible light incident to a first side of the first substrate;   a passivation film disposed on the first side of the first substrate;   a second substrate configured to convert at least infrared light into a first electric signal, wherein the second substrate is an indium gallium arsenide (InGaAs) substrate;   a contact layer disposed between a second side of the first substrate and a first side of the second substrate, wherein the second side of the first substrate is opposite the first side of the first substrate;   a first metal disposed on a second side of the second substrate, wherein the second side of the second substrate is opposite the first side of the second substrate; and   a readout circuit coupled to the second substrate and configured to receive the first electric signal.   
     
     
         2 . The imaging device according to  claim 1 , wherein the first metal receives a first voltage and applies the first voltage to the second substrate. 
     
     
         3 . The imaging device according to  claim 1 , further comprising a second metal bonded to the second substrate. 
     
     
         4 . The imaging device according to  claim 3 , wherein the second metal is electrically connected to the contact layer. 
     
     
         5 . The imaging device according to  claim 1 , wherein the contact layer receives a second voltage. 
     
     
         6 . The imaging device according to  claim 5 , wherein the second voltage is lower than a first voltage. 
     
     
         7 . The imaging device according to  claim 1 , wherein the first substrate is a silicon substrate. 
     
     
         8 . The imaging device according to  claim 1 , further comprising a transfer transistor, a reset transistor, an amplifier transistor. 
     
     
         9 . The imaging device according to  claim 1 , wherein the first substrate includes a photodetector configured to convert the portion of the visible light into a second electric signal. 
     
     
         10 . The imaging device according to  claim 1 , wherein the second substrate is configured to convert only infrared light into the first electric signal. 
     
     
         11 . The imaging device according to  claim 5 , wherein the second voltage is a ground voltage or a common voltage. 
     
     
         12 . The imaging device according to  claim 1 , further comprising a second metal disposed on the second side of the second substrate and electrically connected to the contact layer. 
     
     
         13 . The imaging device according to  claim 12 , wherein the first metal receives a first voltage and applies the first voltage to the second substrate. 
     
     
         14 . The imaging device according to  claim 13 , wherein the first metal receives the first voltage from the readout circuit. 
     
     
         15 . The imaging device according to  claim 13 , wherein the second metal receives a second voltage. 
     
     
         16 . The imaging device according to  claim 15 , wherein the second voltage is lower than the first voltage. 
     
     
         17 . The imaging device according to  claim 16 , wherein the second voltage is a ground voltage or a common voltage.