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. 26, 2000
Filed:
Dec. 01, 1998
United Microelectronics Corp., Hsinchu, TW;
Abstract
A method for forming a hemispherical silicon grain (HSG) layer on a polysilicon electrode is provided. The method is suitable for a substrate, which has a dielectric layer over the substrate with an opening to expose the substrate, and a polysilicon layer is formed over the substrate. A portion of the polysilicon layer is removed above dielectric layer other than the opening region. Each sidewall of the polysilicon layer is slanted so that a trapezoidal polysilicon base is formed. A buffer layer is formed over the trapezoidal polysilicon base. An ion implantation process is performed to form an amorphous silicon layer with sufficient depth on a top surface region of the trapezoidal polysilicon base. The buffer layer includes silicon oxide or silicon nitride. During ion implantation, oxygen or nitrogen elements can also be bombarded into the amorphous silicon layer so as to buffer the amorphous silicon layer to be re-crystallized. A selective HSG layer is formed on the trapezoidal polysilicon electrode base.