Patent ID: 7719036

Claim:
A method of operating a charge coupled device (CCD), comprising: applying a first voltage to a first control gate to create a first well underneath the first control gate and accumulate charge into the first well; applying a second voltage to a second control gate to create a first barrier underneath the second control gate; applying a third voltage to the second control gate to create a second well underneath the second control gate, wherein the first and second wells form a first combined well, and accumulate the charge into the first combined well underneath the first and second control gates; applying a fourth voltage to the first control gate to create a second barrier underneath the first control gate and transfer the charge from the first well underneath the first control gate into the second well underneath the second control gate; and applying a fifth voltage to the second control gate to create a third barrier underneath the second control gate to transfer the charge across a decreasing potential region underneath a first window region, wherein the decreasing potential region comprises a plurality of increasing doping concentrations.