Patent ID: 7786543

Claim:
A MOS or CMOS based active pixel sensor comprising: A) a substrate; B) an array of pixels fabricated in or on said substrate, each pixel comprising a plurality of integrated circuits defining: 1) a charge collection node on which charges generated inside the photodiode are collected, 2) a charge integration node, at which charges generated in said each pixel are integrated to produce pixel signals, 3) a charge sensing node from which reset signals and the pixel signals are sensed; C) an electromagnetic radiation detection structure located above said pixel circuits for converting electromagnetic radiation into charges during charge integration cycles, said electromagnetic detection structure defining a photodiode region for each of said pixels, comprising: 1) a pixel electrode for each pixel, 2) at least one layer of charge generating material to generate charges upon the absorption of electromagnetic radiation, and 3) a surface electrode in the form of a thin transparent layer or grid located above said layer of charge generating material; wherein said plurality of integrated circuits of each of said pixels comprises: 1) integrated circuit elements adapted to maintain voltage potentials of said charge collection nodes substantially constant during charge integration cycles, 2) integrated circuit elements having electrical capacitance adapted to store charges providing an electrical potential at said charge integration node, 3) integrated circuit elements adapted to control the transfer of charges from the charge integration node to the charge sensing node, 4) integrated circuit elements having electrical capacitance adapted to store charges providing an electrical potential at said charge sensing node, 5) integrated circuit elements adapted to reset said charge sensing node, 6) integrated circuit elements adapted to convert the charges on the charge sensing node into electrical signal, and 7) integrated circuit elements adapted to readout electrical signals generated in said pixels.