Transparent asymmetric electrode structure for charge coupled device image sensor

Abstract

A charge coupled device (CCD) image sensor comprises a semiconductor substrate having a transparent insulating layer formed on a light receiving surface thereof, a first set of transfer electrodes disposed in groups of one or more electrodes, said groups being disposed in spaced-apart relation on the insulating layer, and a second set of transfer electrodes disposed on the insulating layer, the electrodes of the second set being disposed in the spaces between the groups of electrodes of the first set and being substantially wider and more uniformly transparent in the visible region of the spectrum than the electrodes of the first set. In the preferred embodiment of the invention, the CCD is a three-phase, three-level device, comprising two levels of slightly overlapping polysilicon electrodes which constitute the first set of transfer electrodes and a third level of substantially unpatterned conductive transparent metal oxide which constitutes the second set of transfer electrodes.

Dependencies are inferred from the claim text.