Dual-wavelength exposure for reduction of implant shadowing

US6913872B1 · kind B1 · utility

Assignee

• Integrated Device Technology, Inc. · US

Inventors

• John L. Sturtevant · Portland, US
• Yiming Gu · Hillsboro, US
• Dyiann Chou · Portland, US
• Chantha Lom · Beaverton, US

Key dates

• Filing date: Sep 30, 2002
• Grant date: Jul 5, 2005
• Expiry date: Apr 3, 2023

Classification

• Technology area (CPC H): Electricity
• CPC primary: H01L21/26586
• WIPO field: Optics
• WIPO sector: Instruments

Abstract

A method for generating a photoresist structure is disclosed in which a layer of photoresist is deposited over a semiconductor substrate. In a first exposure, the layer of photoresist is exposed to deep ultraviolet light. A second exposure is then performed using a different wavelength of light to pattern the layer of photoresist. The photoresist is then developed so as to form a photoresist structure having reduced thickness and rounded corners. This gives a photoresist structure having a reduced shadow area. An angled ion implant can then be performed using the photoresist structure as a mask.