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:
Sep. 13, 2005
Filed:
Oct. 24, 2001
Yushin Takasawa, Tokyo, JP;
Hajime Karasawa, Tokyo, JP;
Yushin Takasawa, Tokyo, JP;
Hajime Karasawa, Tokyo, JP;
Kokusai Electric Co., Ltd., Tokyo, JP;
Abstract
A hemispherical grain (HSG) formation process for enlarging the surface area of a capacitor electrode, wherein stable, defect-free HSG, having outstanding selectivity, is formed. An amorphous silicon layer, which constitutes a capacitor electrode, is formed on an Si wafer, on which is formed a silicon-based dielectric layer, which constitutes an interlevel dielectric layer. An HSG layer, in which there exists practically no defects, is formed on the amorphous silicon layer at a crystal nuclei formation temperature of under 620° C. Further, in accordance with properly controlling the crystal nuclei formation temperature, and the flow rate of monosilane (SiH), which is supplied for crystal nuclei formation, it is possible to furnish selectivity such that HSG nuclei are formed solely on the amorphous silicon layer, without being formed on a silicon-based dielectric layer.