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:
Oct. 02, 2001
Filed:
Jan. 10, 2000
Kun-Chi Lin, Hsin-Chu, TW;
United Microelectronics Corp., Hsin-Chu, TW;
Abstract
The present invention provides a method of forming a contact hole of a DRAM on a semiconductor wafer. The semiconductor wafer comprises a substrate, a conductive layer positioned in a predetermined area of the substrate and a dielectric layer positioned on the surface of the substrate and covering the conductive layer. The method comprises forming an amorphous silicon ( &agr;-Si) layer with an opening on the surface of the dielectric layer wherein the opening is positioned directly above the conductive layer and penetrates to the surface of the dielectric layer, forming a polysilicon layer uniformly on the surface of the amorphous silicon layer and performing a dry etching process to form a contact hole in the dielectric layer, the amorphous silicon layer and the polysilicon layer being used as a hard mask, the contact hole penetrating through the dielectric layer down to the surface of the conductive layer. The polysilicon layer is formed by performing a hemi-spherical grain (HSG) process to improve the resolution limit of the optical exposure tool of the lithographic process.