Abstract: By incorporating an ITO electrode which is more transparent than polysilicon, and designing the pixel such that it has asymmetric gates with as much as possible of its light sensitive region covered by an ITO electrode, light sensitivity is increased. To solve the problem of impurity diffusion from the ITO electrode into the silicon below, the conventional Silicon Dioxide gate dielectric was replaced with an Oxide/Nitride/Oxide stack. Employing at least some polysilicon electrodes with ITO electrodes is desirable to allow entrance passages through which hydrogen passivation can be accomplished. The pixel architecture can be designed to increase sensitivity further by other design choices. The first of these choices is to incorporate a lenslet on each pixel such that as much as possible of the light falling on the pixel is made to pass through the portion of the pixel covered with ITO.

Abstract: By incorporating an ITO electrode which is more transparent than polysilicon, and designing the pixel such that it has asymmetric gates with as much as possible of its light sensitive region covered by an ITO electrode, light sensitivity is increased. To solve the problem of impurity diffusion from the ITO electrode into the silicon below, the conventional Silicon Dioxide gate dielectric was replaced with an Oxide/Nitride/Oxide stack. Employing at least some polysilicon electrodes with ITO electrodes is desirable to allow entrance passages through which hydrogen passivation can be accomplished. The pixel architecture can be designed to increase sensitivity further by other design choices. The first of these choices is to incorporate a lenslet on each pixel such that as much as possible of the light falling on the pixel is made to pass through the portion of the pixel covered with ITO.

Abstract: By designing pixels with highly transparent ITO electrodes and asymmetric gates such that as much light as possible falls upon a region covered by an ITO electrode, light sensitivity is increased. Impurity diffusion from the ITO electrode into the silicon below is prevented by employing an Oxide/Nitride/Oxide stack as a dielectric. Employing at least some polysilicon electrodes with ITO electrodes is desirable to allow entrance passages through which hydrogen passivation can be accomplished. The pixel architecture can be designed to increase sensitivity further by other design choices. The first of these choices is to incorporate a lenslet on each pixel such that as much as possible of the light falling on the pixel is made to pass through the portion of the pixel covered with ITO.