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:
Nov. 24, 1998
Filed:
Nov. 25, 1997
Claymens Lee, Fengshan, TW;
United Semiconductor Corp., Hsinchu, TW;
Abstract
A method for manufacturing a comb-shaped lower electrode for a DRAM capacitor including the steps of providing a substrate having a transistor and an insulating layer formed thereon, wherein the insulating layer contains a contact window opening exposing a source/drain region of the transistor; then, forming a polysilicon layer over the insulating layer, the contact window opening and the exposed source/drain region; next, forming a hemispherical grain silicon over the polysilicon layer. Thereafter, an oxide layer is formed over the hemispherical grain silicon, and then a silicon nitride layer is formed over the gaps between the hemispherical grain silicon exposing portions of the oxide layer. In the subsequent step, a plurality of hard mask layers are formed over the oxide layer not covered by the silicon nitride layer, and finally the silicon nitride layer, the oxide layer and portions of the polysilicon layer are removed using the hard mask layers to form a plurality of trenches.