Method of making memory cell capacitor
US5342800A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Nov 12, 1992 |
| Grant date | Aug 30, 1994 |
| Priority date | — |
| Expiry date | Nov 12, 2012 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S438/964
Abstract
A method for making a memory cell capacitor is disclosed. Steps in accordance with present invention are: (1) forming a capacitor node contact hole after making necessary elements in a semiconductor substrate by depositing an insulation layer and etching a predetermined portion of the insulating layer by a photolithographic process; (2) depositing a doped polysilicon layer, thereby making a contact for connecting the capacitor electrode and a source/drain region in the semiconductor substrate; (3) depositing a silicon nitride layer and a first silicon oxide layer, and opening a window by a photolithographic process in the first silicon nitride layer and the silicon oxide layer at a position where the capacitor storage electrode is to be formed; (4) depositing a hemispherical polysilicon layer having peaks and valleys on the exposed surfaces of the polysilicon layer, the silicon nitride layer, and the first silicon oxide layer; (5) depositing a second oxide layer and etching back the second silicon oxide layer so that it selectively remains in the valleys of the hemispherical polysilicon layer; (6) forming a plurality of polysilicon projections by dry etching the hemispherical polys…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.