Metal-insulator-semiconductor photocell and imager

US6534808B2 · kind B2 · utility

Assignee

• TEXAS INSTRUMENTS INCORPORATED · US

Inventors

• Akitoshi Nishimura · Tsuchiura, JP
• Ichiro Fujii · Gose, JP

Key dates

• Filing date: Jan 11, 2001
• Grant date: Mar 18, 2003
• Expiry date: Jan 11, 2021

Classification

• Technology area (CPC H): Electricity
• CPC primary: H10F30/2823

Abstract

A photocell for detecting light includes at least two tiers or structures, one disposed over the other, each tier having a metal-insulator-semiconductor (M-I-S) or a semiconductor-insulator-metal (S-I-M) structure. Each M-I-S structure includes a semiconductor diffusion layer capable of developing a depletion region, a thin insulator layer disposed on the diffusion layer, and a contact layer disposed on the thin insulator layer. Each S-I-M structure includes a contact layer, a thin insulator layer disposed on the contact layer, and a semiconductor diffusion layer disposed on the thin insulator layer, the semiconductor layer capable of developing a depletion region. When light is incident on each depletion region, a current indicative of the light detected in each depletion region flows through the respective contact layer. Also provided is a semiconductor-insulator-metal (S-I-M) structure that detects light. Two- and three-tiered photocells made of M-I-S and/or S-I-M structures are also provided. Three-tiered photocells are able to detect blue, green, and red components of incident light. These photocells may be arranged in an array to form a photo-imager.