Red/green pixel with simultaneous exposure and improved MTF

US7176544B2 · kind B2 · utility

Assignee

• Dialog Imaging Systems Inc. · DE

Inventors

• Taner Dosluoglu · New York, US
• Michael H. Brill · Levittown, US

Key dates

• Filing date: Mar 31, 2004
• Grant date: Feb 13, 2007
• Expiry date: Aug 31, 2025

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y02E10/548

Abstract

A pixel for detecting red and green light is a single pixel is described. The pixel comprises a deep N well formed in a P type epitaxial substrate. The pixel comprises a deep N well formed in a P type epitaxial substrate. A number of P wells, which are used as the sensor nodes, are formed in the deep N well. The use of these P wells as the sensor nodes improves the modulation transfer function. The depth of the deep N well is about equal to the depth of hole electron pairs generated by red light in silicon. The depth of the P wells is about equal to the depth of hole electron pairs generated by green light in silicon. A red/green signal is determined at each P well by determining the potentials between each of the P wells and the deep N well after a charge integration cycle with the P wells and the deep N well isolated. A green signal is determined at each P well by determining the potentials between each of the P wells and the deep N well after a charge integration cycle with the P wells isolated and the deep N well held at a fixed positive voltage. A red signal at each P well is determined by subtracting the green signal at that P well from the red/green signal at that P well. Th…