Patent ID: 7888715

Claim:
A complementary metal-oxide semiconductor (CMOS) active pixel sensor comprising: a photodiode disposed to generate electric charges in response to an incident light; a transfer transistor disposed to transfer the electric charges integrated in the photodiode to a floating diffusion node, wherein the transfer transistor has a first transfer gate and a second transfer gate, and the first and second transfer gates have a coupled gate structure; a reset transistor disposed to reset a potential level of the floating diffusion node by a given voltage level; and a signal transfer circuit disposed to transfer the potential level of the floating diffusion node to an internal circuit in response to a selection signal, wherein the transfer transistor is disposed to bootstrap a voltage of the second transfer gate by using a voltage coupling effect between the first transfer gate and the second transfer gate before it transfers the electric charges integrated in the photodiode to the floating diffusion node, wherein the first transfer gate is disposed over an entire channel region, and wherein the second transfer gate is disposed over at least a portion of the first transfer gate and at least a portion of the floating diffusion node.