Ion implantation to form trench-bottom oxide of MOSFET

US11695060B2 · kind B2 · utility

Assignee

• Applied Materials, Inc. · US

Inventors

• Qintao Zhang · Mount Kisco, US
• Samphy Hong · Saratoga Springs, US
• Wei Zou · Shanghai, CN
• Lei Zhong · Lo Wu, CN
• David J. Lee · Poughkeepsie, US
• Felix Levitov · Ballston Lake, US

Key dates

• Filing date: Dec 18, 2020
• Grant date: Jul 4, 2023
• Expiry date: Oct 8, 2041

Classification

• Technology area (CPC H): Electricity
• CPC primary: H10D62/8325
• WIPO field: Semiconductors
• WIPO sector: Electrical engineering

Abstract

Disclosed herein are methods for forming MOSFETs. In some embodiments, a method may include providing a device structure including a plurality of trenches, and forming a mask over the device structure including within each of the plurality of trenches and over a top surface of the device structure. The method may further include removing the mask from within the trenches, wherein the mask remains along the top surface of the device structure, and implanting the device structure to form a treated layer along a bottom of the trenches. In some embodiments, the method may further include forming a gate oxide layer along a sidewall of each of the trenches and along the bottom of the trenches, wherein a thickness of the oxide along the bottom of the trenches is greater than a thickness of the oxide along the sidewall of each of the trenches.