×

Low lag transfer gate device

  • US 8,227,844 B2
  • Filed: 01/14/2008
  • Issued: 07/24/2012
  • Est. Priority Date: 01/14/2008
  • Status: Active Grant
First Claim
Patent Images

1. An active pixel sensor (APS) cell structure comprising:

  • a substrate of a first conductivity type material;

    a gate dielectric layer formed on the substrate;

    a gate conductor structure formed on the gate dielectric layer, said gate conductor structure comprising a first doped region of first conductivity type material including an associated first transfer gate electrode and a second doped region of a second conductivity type material including an associated second transfer gate electrode, wherein the first doped region is in direct contact with the second doped region;

    a photosensing device formed at or below a substrate surface adjacent said first doped region of said gate conductor structure for collecting charge carriers in response to light incident thereto;

    a diffusion region of a second conductivity type material formed at or below said substrate surface adjacent said second doped region of said gate conductor structure , said gate conductor structure defining a channel region in said substrate enabling charge transfer between said photosensing device and said diffusion region, andcircuit device including separate conductors entirely physically and electrically isolated from one another to each of said first and second transfer gate electrodes to apply separate voltage signals to each said first and second transfer gate electrodes by direct electrical contact to each of the first and second doped regions, said voltage signals timed for transferring collected charge carriers from said photosensing device to said diffusion region while preventing spillback of charges to said photosensing device.

View all claims
  • 7 Assignments
Timeline View
Assignment View
    ×
    ×