Back Side Illuminated High Dynamic Range 4.0μm Voltage Domain Global Shutter Pixel with Multiple Gain Readout
2019 International Image Sensor Workshop (IISW)
Backside illuminated image sensors with a 4.0μm global shutter (GS) pixel have been fabricated in a 45nm/65nm stacked CMOS process as a proof-of-concept vehicle. The pixel components for photon-to-voltage conversion are formed on the top substrate (the 1st layer). Each photo converted signal from the 1st layer pixel is stored in sample-and-hold (S/H) capacitors on the bottom substrate (the 2nd layer) via micro hybrid-bump (HB) interconnection to achieve a voltage domain GS function. The 2 sets of voltage domain storage capacitor per pixel enable a multiple gain readout to realize single exposure high dynamic range (SEHDR) in the GS operation.