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:
Apr. 18, 2023
Filed:
May. 28, 2021
Yangtze Memory Technologies Co., Ltd., Hubei, CN;
Yu Qi Wang, Wuhan, CN;
Wenjie Zhang, Wuhan, CN;
Hong Guang Song, Wuhan, CN;
Lipeng Liu, Wuhan, CN;
Lianjuan Ren, Wuhan, CN;
Yangtze Memory Technologies Co., Ltd., Wuhan, CN;
Abstract
In a method, a mask is formed on a microstructure over a substrate. The mask includes a first pattern over a first region of the microstructure and a second pattern over a second region of the microstructure. A first etching process is performed to etch the microstructure by providing an etching gas and applying a first bias voltage to the substrate according to the first and second patterns of the mask. A protective layer is subsequently formed by providing a deposition gas and applying a second bias voltage to the substrate to cover the first pattern of the mask. A second etching process is performed to transfer the second pattern of the mask further into the second region of the microstructure. The deposition gas has a higher carbon to fluorine ratio than the etching gas, and the second bias voltage is smaller than the first bias voltage.