Sensor element array having overlapping detection zones

• US 5,629,517 A
• Filed: 04/17/1995
• Issued: 05/13/1997
• Est. Priority Date: 04/17/1995
• Status: Expired due to Term

• Current Assignee: Xerox Corporation (Xerox Holdings Corp.)
• Original Assignee: Xerox Corporation (Xerox Holdings Corp.)
• Inventors: Street, Robert A., Biegelsen, David K., Jackson, Warren B., Weisfield, Richard L.
• Primary Examiner(s): ALLEN, STEPHONE B
• Application Number:
  US08/423,906
• Time in Patent Office: 757 Days
• Field of Search: 250/208.1, 257/59, 257/72, 257/448
• US Class Current: 250/208.1
• CPC Class Codes: H01L 27/1446 in a repetitive configuration

Abstract

An image sensor array has overlapping responsive zones for detecting incident radiation. The sensor array includes a plurality of collection electrodes for sensing charge and a charge distribution layer in contact with the collection electrodes. The charge distribution layer is configured to distribute charge generated from incident radiation to more than one collection electrode, effectively providing overlapping responsive zones that reduce adverse aliasing effects.

Claims

1. An image sensor array having overlapping responsive zones for detecting incident radiation, the image sensor array comprising

a plurality of collection electrodes, each collection electrode having a termination impedance selected to define overlapping responsive zones,

a charge distribution layer in contact with the collection electrodes for distributing charge generated from incident radiation to more than one collection electrode, and

a radiation sensor for creating charge in response to incident radiation in electrical contact with the charge distribution layer, the radiation sensor having an n-type layer and a p-type layer.

2. The image sensor array of claim 1, wherein the radiation sensor further comprises an intrinsic amorphous silicon layer positioned between the n-type layer and the p-type layer to form a p-i-n photodiode.

3. The image sensor array of claim 1, further comprising an auxiliary radiation sensor separated from the radiation sensor by a dielectric layer, with collection electrodes in contact with the second radiation sensor.

4. An image sensor array having overlapping responsive zones for detecting incident radiation, the image sensor array comprising

a plurality of collection electrodes, each collection electrode having a termination impedance selected to define overlapping responsive zones,

a charge distribution layer in contact with the collection electrodes for distributing charge generated from incident radiation to more than one collection electrode in response to said selected termination impedance,

a radiation sensor for creating charge in response to incident radiation in electrical contact with the charge distribution layer, the radiation sensor having an n-type layer and a p-type layer, and

a plurality of pass transistors connected to transfer charge from each of the plurality of collection electrodes.

5. The image sensor array of claim 4, wherein each pass transistor has a drain connected to one of the collection electrodes, a source separated from the drain, and a pass transistor gate electrode controllable to promote transfer of charge from the drain to the source.

6. The image sensor array of claim 4, wherein each of the collection electrodes is a pass transistor in electrical contact with the radiation sensor, the pass transistor being responsive to charge from the radiation sensor to control current passing between a drain and a source.

7. An image sensor array for reducing aliasing artifacts, the image sensor array comprising a plurality of detection zones for producing generated charge, with each detection zone having a charge collection element for holding charge, with local detection response in each detection zone smoothly decreasing with distance from each charge collection element, and wherein neighboring detection zones overlap.