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:
Mar. 23, 1999
Filed:
Mar. 07, 1997
Rohm Co., Ltd., Kyoto, JP;
Abstract
An ONO layer 18 located vicinity of a transistor TR1 for programming is removed. A floating gate FG1 of the transistor TR1 is formed by carrying out etching of a polysilicon layer 16. Then, an inter-layer film SM1 of the transistor TR1 is formed by carrying out oxidation process. The inter-layer film SM1 is formed so as to cover the floating gate FG1. Arsenic is implanted ionically into a semiconductor-substrate 12 using the floating gate FG1 and the inter-layer film SM1 as a mask. Ions of the arsenic thus implanted do not pass through the inter-layer film SM1 and are stopped at the surface. Because the inter-layer film SM1 is made of a silicon oxidation layer formed relatively thick. So that, the inter-layer film SM1 maintains its charge-storage characteristic originally owns even when the ion implantation is carried out.
Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile