Patent ID: 7671315

Claim:
An image sensor comprising: a photodiode comprising an n-doped region and a p-doped region; and a transfer transistor comprising: a gate; a gate oxide layer underneath the gate; a channel underneath the gate oxide layer, the channel comprising a portion of a p-substrate; a source comprising the n-doped region of the photodiode wherein the p-doped region of the photodiode is between the gate oxide layer and the n-doped region of the photodiode; and a drain comprising a floating diffusion node composed of an n+-doped region, wherein the transfer transistor for transferring photon-induced charges created by the photodiode to the floating diffusion node, wherein the channel of the transfer transistor having a depletion region when the transfer transistor is turned on, so that the transfer transistor operates in a pseudo pinch-off mode.