Image sensor

Abstract

An image sensor including an image sensing device layer, a silicon-on-insulator (SOI) layer, an optical device array and a substrate is provided. The SOI layer has a first surface and a second surface. The image sensing device layer is formed on the first surface of the SOI layer. The optical device array is formed on the second surface of the SOI layer. The substrate is disposed above the second surface of the SOI layer; the optical device array is disposed between the substrate and the SOI layer. An incident light coming from the outside environment, passes through the optical device array and the SOI layer, and is received by sensing devices formed in the image sensing device layer. In this manner, the probability of absorption or reflection of the incident light is reduced. Therefore, the sensing performance and the yield of the image sensor of the present invention is improved.

1 . An image sensor, comprising: 
 a silicon-on-insulating layer, having a first surface and a second surface;    an image sensing device layer, disposed over the first surface of the silicon-on-insulating layer;    an optical device array, disposed over the second surface of the silicon-on-insulating layer; and    a substrate, disposed above the second surface of the silicon-on-insulating layer, wherein the optical device array is located between the substrate and the silicon-on-insulating layer.    
   
   
       2 . The image sensor of  claim 1 , wherein the image sensing device layer comprises: 
 an active layer, disposed over the first surface of the silicon-on-insulating layer;    an interconnection layer, disposed over the active layer; and    a plurality of bonding pads, disposed over the interconnection layer, wherein each bonding pad is electrically connected to the interconnection layer.    
   
   
       3 . The image sensor of  claim 2 , wherein the active layer of the image sensing device layer comprises at least one sensing device.  
   
   
       4 . The image sensor of  claim 3 , wherein the sensing device comprises at least one photo diode.  
   
   
       5 . The image sensor of  claim 1 , wherein the optical device array comprises: 
 a plurality of color filters; and    a plurality of condensers, wherein each condenser is disposed over one of the color filters, respectively.    
   
   
       6 . The image sensor of  claim 5 , wherein the condensers comprise a plurality of micro-lenses.  
   
   
       7 . The image sensor of  claim 1 , further comprising a spacer disposed between the second surface of the silicon-on-insulating layer and the substrate in order to hold the substrate above the optical device array.  
   
   
       8 . The image sensor of  claim 1 , further comprising a re-distribution layer disposed above the first surface of the silicon-on-insulating layer, wherein the re-distribution layer is disposed on the image sensing device layer and is electrically connected to the bonding pads.  
   
   
       9 . The image sensor of  claim 8 , further comprising a plurality of bumps disposed over the re-distribution layer, wherein each bump is electrically connected to the re-distribution layer.