Cobalt silicide schottky diode on isolated well

US7485941B2 · kind B2 · utility

Assignee

• TOWER PARTNERS SEMICONDUCTOR CO., LTD. · IL

Inventors

• Sharon Levin · Haifa, IL
• Shye Shapira · Allentown, US
• Ira Naot · Jerusalem, IL
• Robert J. Strain · San Jose, US
• Yossi Netzer · Hadera, IL

Key dates

• Filing date: Oct 21, 2005
• Grant date: Feb 3, 2009
• Expiry date: Feb 13, 2027

Classification

• Technology area (CPC H): Electricity
• CPC primary: H10D84/86

Abstract

A Schottky diode is formed on an isolated well (e.g., a P-well formed in a buried N-well), and utilizes cobalt silicide (CoSi2) structures respectively formed on heavily doped and lightly doped regions of the isolated well to provide the Schottky barrier and backside (ohmic) contact structures of the Schottky diode. The surrounding buried N-well is coupled to a bias voltage. The Schottky barrier and backside contact structures are separated by isolation structures formed using polycrystalline silicon, which is used to form the gate structure of CMOS FETs, in order to minimize forward resistance. Heavily doped drain (HDD) diffusions and lightly doped drain (LDD) diffusions, which are used to form source and drain diffusions of the FET, are utilized to form a suitable contact diffusion under the backside contact silicide.