Corner layout for superjunction device

• US 8,975,720 B2
• Filed: 06/20/2013
• Issued: 03/10/2015
• Est. Priority Date: 02/19/2010
• Status: Active Grant

• Current Assignee: Alpha & Omega Semiconductor, Ltd.
• Original Assignee: Alpha & Omega Semiconductor, Ltd.
• Inventors: Guan, Lingpeng, Bhalla, Anup, Zhu, Tinggang, Bobde, Madhur
• Primary Examiner(s): WOJCIECHOWICZ, EDWARD JOSEPH
• Application Number:
  US13/923,065
• Publication Number:
  US 20130277740A1
• Time in Patent Office: 628 Days
• Field of Search: 257/342, 257/401, 257/483, 257/484
• US Class Current: 257/483
• CPC Class Codes: H01L 29/0634 Multiple reduced surface field (multi-RESURF) structures, e.g. double RESURF, charge compensation, cool, superjunction (SJ), 3D-RESURF, composite buffer (CB) structures
• CPC Class Codes: H01L 29/0638 for preventing surface leakage due to surface inversion layer, e.g. with channel stopper channel stoppers in combination with isolation region for integrated circuits H01L21/762
• CPC Class Codes: H01L 29/0696 of cellular field-effect devices, e.g. multicellular DMOS transistors or IGBTs
• CPC Class Codes: H01L 29/1095 Body region, i.e. base region, of DMOS transistors or IGBTs cell layout H01L29/0696
• CPC Class Codes: H01L 29/402 Field plates
• CPC Class Codes: H01L 29/404 Multiple field plate structures
• CPC Class Codes: H01L 29/47 Schottky barrier electrodes H01L29/435 takes precedence
• CPC Class Codes: H01L 29/7811 with an edge termination structure guard regions per se H01L29/0619; field plates per se H01L29/402
• CPC Class Codes: H01L 29/7823 with an edge termination structure guard regions per se H01L29/0619; field plates per se H01L29/402

Abstract

A superjunction device and methods for layout design and fabrication of a superjunction device are disclosed. A layout of active cell column structures can be configured so that a charge due to first conductivity type dopants balances out charge due to second conductivity type dopants in a doped layer in an active cell region. A layout of end portions of the active cell column structures proximate termination column structures can be configured so that a charge due to the first conductivity type dopants in the end portions and a charge due to the first conductivity type dopants in the termination column structures balances out charge due to the second conductivity type dopants in a portion of the doped layer between the termination column structures and the end portions.

Claims

1. A termination structure for a semiconductor device, comprising:

a channel stop field plate on a surface of a semiconductor material proximate an edge of the semiconductor material, wherein the channel stop field plate includes a metal portion and an isolation portion, wherein the metal portion of the channel stop field plate contacts the semiconductor material without a heavily doped implant region or a body region and thereby forming a Schottky style channel stop, and wherein the channel stop field plate is electrically isolated by the isolation portion from areas of the semiconductor device other than where the Schottky style channel stop is formed.

2. The termination structure of the claim 1 wherein the metal portion of the channel stop field plate contacts a lowly doped portion of the semiconductor material.

3. The termination structure of claim 1 wherein the termination structure is formed on a die containing a semiconductor device, wherein the semiconductor device is a MOSFET.

4. The termination structure of claim 1 wherein the termination structure is formed on a die containing a semiconductor device, wherein the semiconductor device is a superjunction device that includes alternating charge balanced first doped columns of first conductivity type and second doped columns of second conductivity type in an active cell region.