Solid-state imaging element and imaging device

Abstract

To improve detection efficiency in a solid-state imaging element including a SPAD in which an electrode and wiring are placed in a central portion. A solid-state imaging element includes a photodiode and a light collecting section. The photodiode includes a light receiving surface and an electrode placed on the light receiving surface, and that outputs an electrical signal in accordance with light incident on the light receiving surface in a state where a voltage exceeding a breakdown voltage is applied to the electrode. The light collecting section causes light from a subject to be collected in the light receiving surface other than a region where the electrode is placed.

What is claimed is: 
     
         1 . A light detecting device, comprising:
 a semiconductor layer including a light receiving surface;   a first photosensitive region disposed in the semiconductor layer;   an electrode disposed on the light receiving surface of the semiconductor layer, wherein the first photosensitive region outputs an electrical signal in accordance with light incident on the light receiving surface in a state where a voltage exceeding a breakdown voltage is applied to the electrode; and   a plurality of microlenses disposed on the first photosensitive region, wherein the microlenses cause light from a subject to be collected in the first photosensitive region.   
     
     
         2 . The light detecting device of  claim 1 , wherein the electrode is centered in an area of the first semiconductor layer in a top view. 
     
     
         3 . The light detecting device of  claim 2 , wherein the microlenses are disposed around the electrode in the top view. 
     
     
         4 . The light detecting device of  claim 3 , wherein the plurality of microlenses includes four microlenses. 
     
     
         5 . The light detecting device of  claim 4 , further comprising:
 a signal line, wherein the signal line extends from a periphery of the first semiconductor layer to the electrode.   
     
     
         6 . The light detecting device of  claim 5 , wherein the signal line extends along a boundary between two of the four microlenses in the top view. 
     
     
         7 . The light detecting device of  claim 1 , wherein an area of the first photosensitive region is quadrangular in a top view. 
     
     
         8 . The light detecting device of  claim 7 , wherein the electrode is centered in an area of the first semiconductor layer in the top view. 
     
     
         9 . The light detecting device of  claim 8 , wherein the microlenses are disposed around the electrode in the top view. 
     
     
         10 . The light detecting device of  claim 8 , wherein the plurality of microlenses includes four microlenses, and wherein the electrode is centered between the four microlenses in the top view. 
     
     
         11 . The light detecting device of  claim 10 , wherein an outer perimeter of each of the four microlenses is quadrangular in the top view. 
     
     
         12 . The light detecting device of  claim 11 , further comprising:
 a signal line, wherein the signal line extends from a periphery of the first semiconductor layer to the electrode.   
     
     
         13 . The light detecting device of  claim 12 , wherein the signal line extends along a boundary between two of the four microlenses in the top view. 
     
     
         14 . The light detecting device of  claim 7 , wherein an outer perimeter of each of the four microlenses is circular in the top view. 
     
     
         15 . A device, comprising:
 a plurality of pixels disposed in a two-dimensional array, wherein each pixel in the plurality of pixels includes:   a photodiode formed in a semiconductor layer;   an electrode, wherein the electrode is disposed on a light receiving surface of the semiconductor layer; and   a plurality of microlenses, wherein the microlenses are disposed on a light incident surface side of the semiconductor layer, and are further disposed around the electrode in a top view.   
     
     
         16 . The device of  claim 15 , wherein each pixel in the plurality of pixels further includes:
 a signal line, wherein the signal line extends from a periphery of the photodiode to the electrode.   
     
     
         17 . The device of  claim 16 , wherein the signal line extends along a boundary between two of the microlenses in the plurality of microlenses in the top view. 
     
     
         18 . The device of  claim 17 , wherein the plurality of microlenses includes four microlenses. 
     
     
         19 . The device of  claim 18 , wherein an outer perimeter of each of the four microlenses is quadrangular in the top view. 
     
     
         20 . The device of  claim 18 , wherein an outer perimeter of each of the four microlenses is circular in the top view.