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US0O5374578A
United States Patent [19] [li] Patent Number: 5,374,578
Pateletal. [45] Date of Patent: Dec. 20,1994
[54] OZONE GAS PROCESSING FOR
FERROELECTRIC MEMORY CIRCUITS
[75] Inventors: Divyesh N. Patel; Douglas Sheldon, both of Colorado Springs, Colo.
[73] Assignee: Ramtron International Corporation,
Colorado Springs, Colo.
[21] Appl. No.-. 64,746
[22] Filed: May 19,1993
Related U.S. Application Data
[63] Continuation of Ser. No. 841,370, Feb. 25, 1992, abandoned.
[51] Int.C1.5 H01L 21/70
[52] U.S. Q 437/52; 437/47;
437/60; 437/247; 148/DIG. 3
[58] Field of Search 437/47, 48, 52, 60,
437/247,919; 365/145,149; 148/DIG. 3, DIG.
4, DIG. 14, DIG. 43; 257/295
[56] References Cited
U.S. PATENT DOCUMENTS
5,043,049 8/1991 Takenaka 204/192.15
5,075,246 12/1991 Re et al 437/47
5,138,520 8/1992 McMillan et al 361/311
5.142.437 8/1992 Kammerdiner et al 437/313
5.142.438 8/1992 Reinberg et al 437/52
FOREIGN PATENT DOCUMENTS
0380326 8/1990 European Pat. Off. .
0448151 9/1991 European Pat. Off. .
0000163 1/1983 Japan .
0213148 9/1987 Japan .
0187061 7/1990 Japan .
2120849 12/1983 United Kingdom .
Primary Examiner—Tom Thomas
Attorney, Agent, or Firm—Mark J. Murphy; Edward D.
Manzo
[57] ABSTRACT
A method for forming a ferroelectric capacitor for use an integrated circuit establishing one layer over another and then annealing the structure, using an oxygen or ozone anneal, after each layer is established. In particular, an ozone anneal is used after the establishment of a layer of ferroelectric material.
4,589,056 5/1986 Stimmell
25 Claims, 4 Drawing Sheets
