Patent ID: 7893468
Filing Date: 2011-02-22
Classification: H01L

Abstract:
1. A semiconductor structure comprising: a first photosensitive diode located in a first semiconductor layer and comprising a first charge collection well and a first semiconductor portion, wherein said first semiconductor portion abuts a bottom surface of said first charge collection well, includes a first semiconductor material, and has a doping of a first conductivity type, wherein said first charge collection well comprises said first semiconductor material and has a doping of a second conductivity type, wherein said second conductivity type is the opposite of said first conductivity type; and a second photosensitive diode located in a second semiconductor layer which is bonded to said first semiconductor layer and comprising a second charge collection well and a second semiconductor portion, wherein said second semiconductor portion abuts a bottom surface of said second charge collection well, includes a second semiconductor material, and has a doping of said first conductivity type, wherein said second charge collection well comprises said second semiconductor material and has a doping of said second conductivity type, wherein said second semiconductor material is different from said first semiconductor material, and wherein said second photosensitive diode overlies said first photosensitive diode.