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:
Oct. 08, 1996
Filed:
Dec. 07, 1994
James E Nulty, San Jose, CA (US);
Cypress Semiconductor Corporation, San Jose, CA (US);
Abstract
A method of etching an oxide layer is disclosed. First, a resist layer is formed on an oxide layer on a substrate. Next, a photosensitive layer is formed on the oxide layer and patterned to expose regions of the oxide layer to be removed. The exposed regions may overlie a nitride layer, and may overlie a structure such as a polysilicon gate. The etch is performed such that polymer deposits on the photosensitive layer, thus eliminating interactions between the photosensitive layer and the plasma. In this way, a simple etch process allows for good control of the etch, resulting in reduced aspect ratio dependent etch effects, high oxide:nitride selectivity, and good wall angle profile control.