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:
May. 16, 2023
Filed:
Sep. 15, 2020
Method of forming a three-gate non-volatile flash memory cell using two polysilicon deposition steps
Silicon Storage Technology, Inc., San Jose, CA (US);
Feng Zhou, Fremont, CA (US);
Xian Liu, Sunnyvale, CA (US);
Chien-Sheng Su, Saratoga, CA (US);
Nhan Do, Saratoga, CA (US);
Chunming Wang, Shanghai, CN;
Silicon Storage Technology, Inc., San Jose, CA (US);
Abstract
A simplified method for forming a non-volatile memory cell using two polysilicon depositions. A first polysilicon layer is formed on and insulated from the semiconductor substrate in a first polysilicon deposition process. An insulation block is formed on the first polysilicon layer. Spacers are formed adjacent first and second sides of the insulation block, and with the spacer adjacent the first side is reduced. Exposed portions of the first poly silicon layer are removed while maintaining a polysilicon block of the first polysilicon layer disposed under the insulation block. A second polysilicon layer is formed over the substrate and the insulation block in a second polysilicon deposition process. Portions of the second polysilicon layer are removed while maintaining a first polysilicon block (disposed adjacent the first side of the insulation block), and a second polysilicon block (disposed adjacent the second side of the insulation block).