The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Sep. 21, 2021
Filed:
Jul. 03, 2018
Csmc Technologies Fab2 Co., Ltd., Jiangsu, CN;
Shukun Qi, Jiangsu, CN;
Guipeng Sun, Jiangsu, CN;
CSMC TECHNOLOGIES FAB2 CO., LTD., Jiangsu, CN;
Abstract
Disclosed is a method for manufacturing an isolation structure for LDMOS, the method comprising: forming a first groove on the surface of a wafer; filling the first groove with silicon oxide; removing part of the surface of the silicon oxide within the first groove by means of etching; forming a silicon oxide corner structure at the corner of the top of the first groove by means of thermal oxidation; depositing a nitrogen-containing compound on the surface of the wafer to cover the surface of the silicon oxide within the first groove and the surface of the silicon oxide corner structure; dry-etching the nitrogen-containing compound to remove the nitrogen-containing compound from the surface of the silicon oxide within the first groove, and thereby forming a nitrogen-containing compound side wall residue; with the nitrogen-containing compound side wall residue as a mask, continuing to etch downwards to form a second groove; forming a silicon oxide layer on the side wall and the bottom of the second groove; removing the nitrogen-containing compound side wall residue; and filling the first groove and the second groove with silicon oxide.