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. 30, 2004
Filed:
Mar. 17, 2003
Shuo Gu, Fremont, CA (US);
Matrix Semiconductor, Inc., Santa Clara, CA (US);
Abstract
A method to enhance grain size in polysilicon films while avoiding formation of hemispherical grains (HSG) is disclosed. The method begins by depositing a first amorphous silicon film, then depositing silicon nuclei, which will act as nucleation sites, on the amorphous film. After deposition of silicon nuclei, crystallization, and specifically HSG, is prevented by lowering temperature and/or raising pressure. Next a second amorphous silicon layer is deposited over the first layer and the nuclei. Finally an anneal is performed to induce crystallization from the embedded nuclei. Thus grains are formed from the silicon bulk, rather than from the surface, HSG is avoided, and a smooth polysilicon film with enhanced grain size is produced.