Solid-state imaging apparatus and imaging system

Abstract

Provided is a solid-state imaging apparatus, including pixels each including: a photoelectric conversion unit; a charge accumulation unit; a transistor including a control electrode; a waveguide; and a light-shielding portion. The waveguide includes an incident portion and an output portion, the light-shielding portion includes a first portion that covers the control electrode of the transistor and a second portion that covers a part of the photoelectric conversion unit, the output portion and the photoelectric conversion unit are arranged with an interval therebetween, the interval between the output portion and the photoelectric conversion unit is larger than an interval between a lower end of the second portion of the light-shielding portion and the photoelectric conversion unit, and the interval between the output portion and the photoelectric conversion unit is smaller than an interval between an upper end of the second portion of the light-shielding portion and the photoelectric conversion unit.

1 .- 19 . (canceled) 
     
     
         20 . A photoelectric conversion apparatus, comprising:
 a semiconductor substrate;   a plurality of pixels arranged in the semiconductor substrate, each pixel including a photoelectric conversion unit configured to generate a signal charge by photoelectric conversion of incident light, a charge accumulation unit configured to accumulate the signal charge transferred from the photoelectric conversion unit, a transistor configured to transfer the signal charge from the photoelectric conversion unit to the charge accumulation unit, the transistor including a gate electrode, and a floating diffusion portion configured to receive the signal charge transferred from the charge accumulation unit;   a waveguide configured to guide the incident light into the photoelectric conversion unit;   a light-shielding portion covering at least the gate electrode and the charge accumulation unit; and   a plurality of wiring layers arranged above the light-shielding portion so that the plurality of wiring layers overlap with the light-shielding portion when viewed in a planer view, the light shielding portion being arranged between the plurality of wiring layers and the substrate,   wherein:   the waveguide has an upper end located at a position farther from the semiconductor substrate than at least a part of the plurality of wiring layers and a lower end located at a position closer to the semiconductor substrate than the at least part of the plurality of wiring layers,   an insulating layer is arranged between the lower end of the waveguide and the semiconductor substrate, and   a distance between the lower end of the waveguide and the semiconductor substrate is smaller than a distance between an upper end of the light-shielding portion and the semiconductor substrate.   
     
     
         21 . The photoelectric conversion apparatus according to  claim 20 , wherein the insulating layer includes a silicon-nitride. 
     
     
         22 . The photoelectric conversion apparatus according to  claim 21 , wherein the insulating layer includes a portion arranged between the light-shielding portion and the gate electrode, the portion overlapping with the gate electrode when viewed in the planar view. 
     
     
         23 . The photoelectric conversion apparatus according to  claim 22 , further comprising a second insulating layer arranged between the light-shielding portion and the portion of the insulating layer overlapping with the gate electrode. 
     
     
         24 . The photoelectric conversion apparatus according to  claim 23 , further comprising a third insulating layer arranged between the insulating layer and the substrate, wherein the third insulating layer includes a silicon oxide. 
     
     
         25 . The photoelectric conversion apparatus according to  claim 24 , wherein the third insulating layer includes a portion arranged between the gate electrode and the substrate. 
     
     
         26 . The photoelectric conversion apparatus according to  claim 25 , wherein the insulating layer forms a reflection preventing layer. 
     
     
         27 . The photoelectric conversion apparatus according to  claim 26 , wherein the portion of the third insulating layer arranged between the gate electrode and the substrate forms a gate insulating film. 
     
     
         28 . The photoelectric conversion apparatus according to  claim 20 , further comprising a second transistor configured to discharge the signal charge from the photoelectric conversion unit to a drain portion, the second transistor including a second gate electrode. 
     
     
         29 . The photoelectric conversion apparatus according to  claim 28 , wherein the light-shielding portion covers at least a portion of the second gate electrode. 
     
     
         30 . The photoelectric conversion apparatus according to  claim 28 , further comprising a third insulating layer arranged between the insulating layer and the substrate,
 wherein the third insulating layer includes a silicon oxide, and   wherein the third insulating layer includes a portion arranged between the second gate electrode and the substrate.   
     
     
         31 . The photoelectric conversion apparatus according to  claim 25 , further comprising a second transistor configured to discharge the signal charge from the photoelectric conversion unit to a drain portion, the second transistor including a second gate electrode. 
     
     
         32 . The photoelectric conversion apparatus according to  claim 31 , wherein the light-shielding portion covers at least a portion of the second gate electrode. 
     
     
         33 . The photoelectric conversion apparatus according to  claim 32 , wherein the third insulating layer includes a second portion arranged between the second gate electrode and the substrate. 
     
     
         34 . The photoelectric conversion apparatus according to  claim 20 , wherein a width of an opening of the light-shielding portion is larger than a width of the lower end of the waveguide. 
     
     
         35 . The photoelectric conversion apparatus according to  claim 20 , wherein a width of the upper end of the waveguide is larger than a width of the lower end of the waveguide. 
     
     
         36 . The photoelectric conversion apparatus according to  claim 25 ,
 wherein a width of an opening of the light-shielding portion is larger than a width of the lower end of the waveguide, and   wherein a width of the upper end of the waveguide is larger than a width of the lower end of the waveguide.   
     
     
         37 . The photoelectric conversion apparatus according to  claim 33 ,
 wherein a width of an opening of the light-shielding portion is larger than a width of the lower end of the waveguide, and   wherein a width of the upper end of the waveguide is larger than a width of the lower end of the waveguide.   
     
     
         38 . The photoelectric conversion apparatus according to  claim 20 , wherein the waveguide includes a carbon. 
     
     
         39 . The photoelectric conversion apparatus according to  claim 20 , wherein the waveguide includes an organic material. 
     
     
         40 . The photoelectric conversion apparatus according to  claim 25 , wherein the waveguide includes a carbon. 
     
     
         41 . The photoelectric conversion apparatus according to  claim 25 , wherein the waveguide includes an organic material. 
     
     
         42 . The photoelectric conversion apparatus according to  claim 33 , wherein the waveguide includes a carbon. 
     
     
         43 . The photoelectric conversion apparatus according to  claim 33 , wherein the waveguide includes an organic material. 
     
     
         44 . The photoelectric conversion apparatus according to  claim 37 , wherein the waveguide includes a carbon. 
     
     
         45 . The photoelectric conversion apparatus according to  claim 37 , wherein the waveguide includes an organic material. 
     
     
         46 . The photoelectric conversion apparatus according to  claim 20 , wherein at least a part of an edge of an opening of the light-shielding portion is positioned between the upper end and the lower end when viewed in the planar view. 
     
     
         47 . The photoelectric conversion apparatus according to  claim 20 , wherein a width of an opening of the light-shielding portion is larger than a width of the lower end and smaller than a width of the upper end. 
     
     
         48 . The photoelectric conversion apparatus according to  claim 20 , wherein the lower end of the waveguide includes an interface between the waveguide and an etching stop layer. 
     
     
         49 . The photoelectric conversion apparatus according to  claim 20 , wherein the lower end of the waveguide includes an interface between the waveguide and an interlayer insulating layer. 
     
     
         50 . The photoelectric conversion apparatus according to  claim 20 , wherein the lower end of the waveguide has a shape having a difference in level. 
     
     
         51 . The photoelectric conversion apparatus according to  claim 20 , wherein the light-shielding portion includes a first portion which is arranged at a same height from the semiconductor substrate as the gate electrode and a second portion which is arranged above the gate electrode. 
     
     
         52 . The photoelectric conversion apparatus according to  claim 51 ,
 wherein the first portion and the gate electrode are provided with a distance therebetween, and   the second portion and the gate electrode are provided with a distance therebetween.   
     
     
         53 . The photoelectric conversion apparatus according to  claim 52 ,
 wherein the light-shielding portion includes a third portion which is arranged at a same height as the gate electrode, and   the gate electrode is arranged between the first portion and the third portion in a cross section including the gate electrode and the light-shielding portion.   
     
     
         54 . The photoelectric conversion apparatus according to  claim 53 , wherein the charge accumulation unit includes a first semiconductor region of a first conductivity type holding the signal charge and a second semiconductor region of a second conductivity type arranged between the first semiconductor region and the light-shielding portion. 
     
     
         55 . The photoelectric conversion apparatus according to  claim 53 , further comprising a color filter and a microlens which are arranged above the waveguide. 
     
     
         56 . The photoelectric conversion apparatus according to  claim 25 , further comprising a color filter and a microlens which are arranged above the waveguide. 
     
     
         57 . The photoelectric conversion apparatus according to  claim 33 , further comprising a color filter and a microlens which are arranged above the waveguide. 
     
     
         58 . The photoelectric conversion apparatus according to  claim 37 , further comprising a color filter and a microlens which are arranged above the waveguide. 
     
     
         59 . A photoelectric conversion apparatus, comprising:
 a semiconductor substrate;   a plurality of pixels arranged in the semiconductor substrate, each pixel including a photoelectric conversion unit configured to generate a signal charge by photoelectric conversion of incident light, a charge accumulation unit configured to accumulate the signal charge transferred from the photoelectric conversion unit, a transistor configured to transfer the signal charge from the photoelectric conversion unit to the charge accumulation unit, the transistor including a gate electrode, and a floating diffusion portion configured to receive the signal charge transferred from the charge accumulation unit;   a waveguide configured to guide the incident light into the photoelectric conversion unit;   a light-shielding portion covering at least the gate electrode and the charge accumulation unit; and   a plurality of wiring layers arranged above the light-shielding portion so that the plurality of wiring layers overlap with the light-shielding portion when viewed in a planer view, the light shielding portion being arranged between the plurality of wiring layers and the substrate,   wherein:   an insulating layer is arranged between the waveguide and the semiconductor substrate, and   the waveguide includes a first portion which is arranged at a same height from the semiconductor substrate as at least one of the plurality of wiring layers and a second portion which is arranged at a same height from the semiconductor substrate as at least a part of the light-shielding portion.   
     
     
         60 . The photoelectric conversion apparatus according to  claim 59 , wherein the insulating layer includes a silicon-nitride. 
     
     
         61 . The photoelectric conversion apparatus according to  claim 60 , wherein the insulating layer includes a portion arranged between the light-shielding portion and the gate electrode, the portion overlapping with the gate electrode when viewed in the planar view. 
     
     
         62 . The photoelectric conversion apparatus according to  claim 61 , further comprising a second insulating layer arranged between the light-shielding portion and the portion of the insulating layer overlapping with the gate electrode. 
     
     
         63 . The photoelectric conversion apparatus according to  claim 62 , further comprising a third insulating layer arranged between the insulating layer and the substrate, wherein the third insulating layer includes a silicon oxide. 
     
     
         64 . The photoelectric conversion apparatus according to  claim 63 , wherein the third insulating layer includes a portion arranged between the gate electrode and the substrate. 
     
     
         65 . The photoelectric conversion apparatus according to  claim 64 , wherein the insulating layer forms a reflection preventing layer. 
     
     
         66 . The photoelectric conversion apparatus according to  claim 65 , wherein the portion of the third insulating layer arranged between the gate electrode and the substrate forms a gate insulating film. 
     
     
         67 . The photoelectric conversion apparatus according to  claim 59 , further comprising a second transistor configured to discharge the signal charge from the photoelectric conversion unit to a drain portion, the second transistor including a second gate electrode. 
     
     
         68 . The photoelectric conversion apparatus according to  claim 67 , wherein the light-shielding portion covers at least a portion of the second gate electrode. 
     
     
         69 . The photoelectric conversion apparatus according to  claim 67 , further comprising a third insulating layer arranged between the insulating layer and the substrate,
 wherein the third insulating layer includes a silicon oxide, and   wherein the third insulating layer includes a portion arranged between the second gate electrode and the substrate.   
     
     
         70 . The photoelectric conversion apparatus according to  claim 64 , further comprising a second transistor configured to discharge the signal charge from the photoelectric conversion unit to a drain portion, the second transistor including a second gate electrode. 
     
     
         71 . The photoelectric conversion apparatus according to  claim 70 , wherein the light-shielding portion covers at least a portion of the second gate electrode. 
     
     
         72 . The photoelectric conversion apparatus according to  claim 71 , wherein the third insulating layer includes a second portion arranged between the second gate electrode and the substrate. 
     
     
         73 . The photoelectric conversion apparatus according to  claim 59 , wherein a width of an opening of the light-shielding portion is larger than a width of a lower end of the waveguide. 
     
     
         74 . The photoelectric conversion apparatus according to  claim 59 , wherein a width of an upper end of the waveguide is larger than a width of a lower end of the waveguide. 
     
     
         75 . The photoelectric conversion apparatus according to  claim 64 ,
 wherein a width of an opening of the light-shielding portion is larger than a width of a lower end of the waveguide, and   wherein a width of an upper end of the waveguide is larger than a width of a lower end of the waveguide.   
     
     
         76 . The photoelectric conversion apparatus according to  claim 65 ,
 wherein a width of an opening of the light-shielding portion is larger than a width of a lower end of the waveguide, and   wherein a width of an upper end of the waveguide is larger than a width of a lower end of the waveguide.   
     
     
         77 . The photoelectric conversion apparatus according to  claim 59 , wherein the waveguide includes a carbon. 
     
     
         78 . The photoelectric conversion apparatus according to  claim 59 , wherein the waveguide includes an organic material. 
     
     
         79 . The photoelectric conversion apparatus according to  claim 64 , wherein the waveguide includes a carbon. 
     
     
         80 . The photoelectric conversion apparatus according to  claim 64 , wherein the waveguide includes an organic material. 
     
     
         81 . The photoelectric conversion apparatus according to  claim 72 , wherein the waveguide includes a carbon. 
     
     
         82 . The photoelectric conversion apparatus according to  claim 72 , wherein the waveguide includes an organic material. 
     
     
         83 . The photoelectric conversion apparatus according to  claim 76 , wherein the waveguide includes a carbon. 
     
     
         84 . The photoelectric conversion apparatus according to  claim 76 , wherein the waveguide includes an organic material. 
     
     
         85 . The photoelectric conversion apparatus according to  claim 59 , wherein at least a part of an edge of an opening of the light-shielding portion is positioned between an upper end of the waveguide and a lower end of the waveguide when viewed in the planar view. 
     
     
         86 . The photoelectric conversion apparatus according to  claim 59 , wherein a width of an opening of the light-shielding portion is larger than a width of a lower end of the waveguide and smaller than a width of an upper end of the waveguide. 
     
     
         87 . The photoelectric conversion apparatus according to  claim 59 , wherein the lower end of the waveguide includes an interface between the waveguide and an etching stop layer. 
     
     
         88 . The photoelectric conversion apparatus according to  claim 59 , wherein the lower end of the waveguide includes an interface between the waveguide and an interlayer insulating layer. 
     
     
         89 . The photoelectric conversion apparatus according to  claim 59 , wherein the light-shielding portion includes a first portion which is arranged at a same height from the semiconductor substrate as the gate electrode and a second portion which is arranged above the gate electrode. 
     
     
         90 . The photoelectric conversion apparatus according to  claim 89 ,
 wherein the first portion and the gate electrode are provided with a distance therebetween, and   the second portion and the gate electrode are provided with a distance therebetween.   
     
     
         91 . The photoelectric conversion apparatus according to  claim 90 ,
 wherein the light-shielding portion includes a third portion which is arranged at a same height as the gate electrode, and   the gate electrode is arranged between the first portion and the third portion in a cross section including the gate electrode and the light-shielding portion.   
     
     
         92 . The photoelectric conversion apparatus according to  claim 91 , wherein the charge accumulation unit includes a first semiconductor region of a first conductivity type holding the signal charge and a second semiconductor region of a second conductivity type arranged between the first semiconductor region and the light-shielding portion. 
     
     
         93 . The photoelectric conversion apparatus according to  claim 91 , further comprising a color filter and a microlens which are arranged above the waveguide. 
     
     
         94 . The photoelectric conversion apparatus according to  claim 64 , further comprising a color filter and a microlens which are arranged above the waveguide. 
     
     
         95 . The photoelectric conversion apparatus according to  claim 72 , further comprising a color filter and a microlens which are arranged above the waveguide. 
     
     
         96 . The photoelectric conversion apparatus according to  claim 76 , further comprising a color filter and a microlens which are arranged above the waveguide. 
     
     
         97 . An imaging system, comprising:
 the photoelectric conversion apparatus according to  claim 20 ; and   an image signal processing unit configured to process a signal output from the photoelectric conversion apparatus.   
     
     
         98 . An imaging system, comprising:
 the photoelectric conversion apparatus according to  claim 59 ; and   an image signal processing unit configured to process a signal output from the photoelectric conversion apparatus.   
     
     
         99 . A photoelectric conversion apparatus, comprising:
 a plurality of pixels, each pixel including a photoelectric conversion unit configured to generate a signal charge by photoelectric conversion of incident light, a charge accumulation unit configured to accumulate the signal charge transferred from the photoelectric conversion unit, a transistor configured to transfer the signal charge from the photoelectric conversion unit to the charge accumulation unit, the transistor including a gate electrode, and a floating diffusion portion configured to receive the signal charge transferred from the charge accumulation unit;   a waveguide configured to guide the incident light into the photoelectric conversion unit; and   a light-shielding portion covering at least a part of the charge accumulation unit and at least a part of the gate electrode of the transistor, and having a portion which is between the waveguide and the gate electrode of the transistor,   wherein:   the photoelectric conversion unit, the charge accumulation unit, and the floating diffusion portion are included in a substrate,   a second distance between the waveguide and the substrate is longer than a first distance between the portion of the light-shielding portion and the substrate, and   the second distance is shorter than a sum of the first distance and a thickness of the light-shielding portion.   
     
     
         100 . The photoelectric conversion apparatus according to  claim 99 , further comprising:
 a plurality of wiring layers provided above the light-shielding portion; and   an insulating layer provided between the plurality of wiring layers,   wherein the waveguide has a refractive index higher than a refractive index of the insulating layer.   
     
     
         101 . The photoelectric conversion apparatus according to  claim 100 , further comprising an etching stop layer arranged between the waveguide and the substrate. 
     
     
         102 . The photoelectric conversion apparatus according to  claim 101 , wherein an angle of a side surface of the waveguide is set to 39.8° or less with respect to a direction normal to the substrate. 
     
     
         103 . The photoelectric conversion apparatus according to  claim 99 , wherein:
 the waveguide comprises an incident portion which the light enters and an output portion from which the light is output,   the light-shielding portion has an opening, and   a width of the opening is larger than a width of the output portion and smaller than a width of the incident portion.   
     
     
         104 . The photoelectric conversion apparatus according to  claim 99 , wherein:
 the photoelectric conversion unit includes a first semiconductor region of a first conductivity type and a second semiconductor region of a second conductivity type, arranged in the substrate,   the second semiconductor region forms at least a part of the substrate, and   the first semiconductor region is arranged below the second semiconductor region and configured to accumulate the signal charge.   
     
     
         105 . The photoelectric conversion apparatus according to  claim 99 , wherein each of the plurality of pixels includes a second transistor configured to transfer the signal charge from the charge accumulation unit to the floating diffusion portion. 
     
     
         106 . The photoelectric conversion apparatus according to  claim 99 ,
 wherein, in the planar view, the photoelectric conversion unit and the charge accumulation unit are arranged in a first direction, and   in the planar view, the photoelectric conversion unit and floating diffusion portion are arranged in a second direction which is different from the first direction.   
     
     
         107 . A photoelectric conversion apparatus, comprising:
 a plurality of pixels, each pixel including a photoelectric conversion unit configured to generate a signal charge by photoelectric conversion of incident light, a charge accumulation unit configured to accumulate the signal charge transferred from the photoelectric conversion unit, a transistor configured to transfer the signal charge from the photoelectric conversion unit to the charge accumulation unit, the transistor including a gate electrode, and a floating diffusion portion configured to receive the signal charge transferred from the charge accumulation unit;   a waveguide configured to guide the incident light into the photoelectric conversion unit; and   a light-shielding portion covering at least a part of the charge accumulation unit, at least a part of the gate electrode of the transistor and at least a part of the photoelectric conversion unit,   wherein:   the light-shielding portion is arranged with an interval of a first distance from a surface of the photoelectric conversion unit,   a second distance between the waveguide and the surface of the photoelectric conversion unit is longer than the first distance, and   the second distance is shorter than a sum of the first distance and a thickness of a part of the light-shielding portion covering the part of the photoelectric conversion unit.   
     
     
         108 . The photoelectric conversion according to  claim 107 , further comprising:
 a plurality of wiring layers provided above the light-shielding portion; and   an insulating layer provided between the plurality of wiring layers,   wherein the waveguide has a refractive index higher than a refractive index of the insulating layer.   
     
     
         109 . The photoelectric conversion apparatus according to  claim 108 , further comprising an etching stop layer arranged between the waveguide and the surface of the photoelectric conversion unit. 
     
     
         110 . The photoelectric conversion apparatus according to  claim 109 , wherein an angle of a side surface of the waveguide is set to 39.8° or less with respect to a direction normal to the surface of the photoelectric conversion unit. 
     
     
         111 . The photoelectric conversion apparatus according to  claim 107 , wherein the waveguide comprises an incident portion which the light enters and an output portion from which the light is output,
 an opening formed by the light-shielding portion, and   a width of the opening is larger than a width of the output portion and smaller than a width of the incident portion.   
     
     
         112 . The photoelectric conversion apparatus according to  claim 107 , wherein:
 the photoelectric conversion unit includes a first semiconductor region of a first conductivity type and a second semiconductor region of a second conductivity type,   the second semiconductor region is provided in contact with a surface of a semiconductor substrate and forms at least a part of the surface of the photoelectric conversion unit, and   the first semiconductor region is arranged below the second semiconductor region and configured to accumulate the signal charge.   
     
     
         113 . The photoelectric conversion apparatus according to  claim 107 , wherein each of the plurality of pixels includes a second transistor configured to transfer the signal charge from the charge accumulation unit to the floating diffusion portion. 
     
     
         114 . The photoelectric conversion apparatus according to  claim 107 ,
 wherein, in a planar view, the photoelectric conversion unit and the charge accumulation unit are arranged in a first direction, and   in the planar view, the photoelectric conversion unit and floating diffusion portion are arranged in a second direction which is different from the first direction.   
     
     
         115 . A photoelectric conversion apparatus, comprising:
 a plurality of pixels, each pixel including a photoelectric conversion unit configured to generate a signal charge by photoelectric conversion of incident light, a charge accumulation unit configured to accumulate the signal charge transferred from the photoelectric conversion unit, a transistor configured to transfer the signal charge from the photoelectric conversion unit to the charge accumulation unit, the transistor including a gate electrode, and a floating diffusion portion configured to receive the signal charge transferred from the charge accumulation unit;   a waveguide configured to guide the incident light into the photoelectric conversion unit; and   a light-shielding portion covering at least a part of the charge accumulation unit, at least a part of the gate electrode of the transistor and at least a part of the photoelectric conversion unit, wherein:   the light-shielding portion is arranged with an interval of a first distance from a surface of the photoelectric conversion unit,   a second distance between the waveguide and the surface of the photoelectric conversion unit is longer than the first distance,   the waveguide comprises an incident portion which the light enters and an output portion from which the light is output, and   at least a part of an end of the light-shielding portion is located between an outer edge of the incident portion and an outer edge of the output portion, when viewed from an optical axis direction of the waveguide.   
     
     
         116 . The photoelectric conversion apparatus according to  claim 115 , wherein the second distance is shorter than a sum of the first distance and a thickness of a part of the light-shielding portion covering the part of the photoelectric conversion unit. 
     
     
         117 . The photoelectric conversion apparatus according to  claim 115 , wherein the second distance is longer than a sum of the first distance and a thickness of a part of the light-shielding portion covering the part of the photoelectric conversion unit. 
     
     
         118 . The photoelectric conversion apparatus according to  claim 115 , further comprising:
 a plurality of wiring layers provided above the light-shielding portion; and   an insulating layer provided between the plurality of wiring layers,   wherein the waveguide has a refractive index higher than a refractive index of the insulating layer.   
     
     
         119 . The photoelectric conversion apparatus according to  claim 118 , further comprising an etching stop layer arranged between the waveguide and the surface of the photoelectric conversion unit. 
     
     
         120 . The photoelectric conversion apparatus according to  claim 119 , wherein an angle of a side surface of the waveguide is set to 39.8° or less with respect to a direction normal to the surface of the photoelectric conversion unit. 
     
     
         121 . The photoelectric conversion apparatus according to  claim 115 , wherein:
 the waveguide further comprises   an opening formed by the light-shielding portion, and   a width of the opening is larger than a width of the output portion and smaller than a width of the incident portion.   
     
     
         122 . The photoelectric conversion apparatus according to  claim 115 , wherein:
 the photoelectric conversion unit includes a first semiconductor region of a first conductivity type and a second semiconductor region of a second conductivity type,   the second semiconductor region is provided in contact with a surface of a semiconductor substrate and forms at least a part of the surface of the photoelectric conversion unit, and   the first semiconductor region is arranged below the second semiconductor region and configured to accumulate the signal charge.   
     
     
         123 . The photoelectric conversion apparatus according to  claim 115 , wherein each of the plurality of pixels includes a second transistor configured to transfer the signal charge from the charge accumulation unit to the floating diffusion portion. 
     
     
         124 . The photoelectric conversion apparatus according to  claim 115 ,
 wherein, in a planar view, the photoelectric conversion unit and the charge accumulation unit are arranged in a first direction, and   in the planar view, the photoelectric conversion unit and floating diffusion portion are arranged in a second direction which is different from the first direction.