3d stacked apd/spad for visible light operating at high speed

An optical receiver system comprising:

• a pixel array comprising a plurality of pixels arranged in a two-dimensional pattern, each pixel comprising a plurality of sub-pixels, wherein each sub-pixel comprises a shaped p-type layer and a shaped n-type layer;
• a bundle of optical communication links, each optical communication link of the bundle aligned to a corresponding pixel of the plurality of pixels, the bundle of optical communication links having a fiber pitch of 25 μm to 50 μm;
• an application-specific integrated circuit (ASIC) fabricated on a separate substrate from the pixel array in a 3D stacked configuration, the ASIC coupled to the pixel array;
• deep trench isolation (DTI) regions separating adjacent pixels;
• and
• shallow trench isolation (STI) regions separating adjacent sub-pixels within a pixel.

A photodetector array system comprising:

• a pixel array comprising a plurality of backside illumination (BSI) photodiode structures arranged in a two-dimensional pattern, each BSI photodiode structure comprising a plurality of sub-pixels;
• a plurality of microlenses, each microlens aligned to a corresponding sub-pixel of the plurality of sub-pixels;
• an application-specific integrated circuit (ASIC) fabricated using a first process node of 20 nm and coupled to the pixel array, the pixel array fabricated using a second process node of 40 nm or larger;
• wherein each sub-pixel comprises a shaped p-type layer and a shaped n-type layer;
• and
• wherein each BSI photodiode structure comprises a p-type doped region positioned within a thickness of a backside of the BSI photodiode structure.