Method of making an insulated gate semiconductor device having a shield electrode structure

US9029215B2 · kind B2 · utility

Assignee

• SEMICONDUCTOR COMPONENTS INDUSTRIES, LLC · US

Inventors

• Zia Hossain · Tempe, US
• Gordon M. Grivna · Mesa, US
• Duane B. Barber · Portland, US
• Peter McGrath · Portland, US
• Balaji Padmanabhan · Chandler, US
• Prasad Venkatraman · Gilbert, US

Key dates

• Filing date: May 14, 2012
• Grant date: May 12, 2015
• Expiry date: Jan 24, 2033

Classification

• Technology area (CPC H): Electricity
• CPC primary: H10D64/663

Abstract

In one embodiment, a method for forming a semiconductor device includes forming trench and a dielectric layer along surfaces of the trench. A shield electrode is formed in a lower portion of the trench and the dielectric layer is removed from upper sidewall surfaces of the trench. A gate dielectric layer is formed along the upper surfaces of the trench. Oxidation-resistant spacers are formed along the gate dielectric layer. Thereafter, an interpoly dielectric layer is formed above the shield electrode using localized oxidation. The oxidation step increases the thickness of lower portions of the gate dielectric layer. The oxidation-resistant spacers are removed before forming a gate electrode adjacent the gate dielectric layer.