Claims
- 1. A method of manufacturing a DRAM having a memory mat portion and a peripheral circuit portion, comprising the steps of:forming a thermal oxide film on a semiconductor substrate surface; depositing a silicon nitride film on said thermal oxide film; patterning said silicon nitride film in accordance with an active region; etching said thermal oxide film and said silicon substrate with the patterned silicon nitride film used as a mask to form grooves in a field region; depositing an insulating film; partly etching said insulating film in such a manner that a plurality of pillars of said insulating film are left for said memory mat portion; exposing said patterned silicon nitride film by chemical mechanical polishing; and removing said exposed silicon nitride film; wherein one of said pillars left by said step of partly etching said insulating film has a surface area in plan view that is larger than a surface area in plan view of an active region formed beneath said one of said pillars, and said one of said pillars is over a plurality of active regions formed for said memory mat portion.
- 2. A method according to claim 1, wherein said step of partly etching said insulating film is performed so that a volume of said insulating film for said peripheral circuit portion remaining after said step of partly etching and to be removed by said chemical mechanical polishing, and a volume of said insulating film for said memory mat portion remaining after said step of partly etching, are equal to each other.
Priority Claims (2)
Number |
Date |
Country |
Kind |
10-083236 |
Mar 1998 |
JP |
|
11-074999 |
Mar 1999 |
JP |
|
Parent Case Info
This is a continuation application of U.S. Ser. No. 09/276,969, which was filed on Mar. 26, 1999 now U.S. Pat. No. 6,204,184.
US Referenced Citations (7)
Foreign Referenced Citations (8)
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6-295908 |
Oct 1991 |
JP |
07-235537 |
Sep 1995 |
JP |
7-263537 |
Oct 1995 |
JP |
8-008216 |
Jan 1996 |
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May 1998 |
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10-321625 |
Dec 1998 |
JP |
10-321628 |
Dec 1998 |
JP |
83102442 |
Sep 1995 |
TW |
Continuations (1)
|
Number |
Date |
Country |
Parent |
09/276969 |
Mar 1999 |
US |
Child |
09/750061 |
|
US |