Process for fabricating electronic circuits with anodically oxidized ...

United States Patent [w]

Zhang et al.

US005830786A [ii] Patent Number: [45] Date of Patent:

5,830,786 Nov. 3, 1998

[54] PROCESS FOR FABRICATING
ELECTRONIC CIRCUITS WITH
ANODICALLY OXIDIZED SCANDIUM
DOPED ALUMINUM WIRING

[75] Inventors: Hongyong Zhang; Hideki Uochi, both of Kanagawa; Shunpei Yamazaki, Tokyo; Yasuhiko Takemura, Kanagawa; Minoru Miyazaki, Kanagawa; Akane Murakami, Kanagawa; Toshimitsu Konuma, Kanagawa; Akira Sugawara, Kanagawa; Yukiko Uehara, Kanagawa, all of Japan

[73] Assignee: Semiconductor Energy Laboratory Co., Ltd., Kanagawa, Japan

[21] Appl. No.: 654,030

[22] Filed: May 28, 1996

Related U.S. Application Data

[63] Continuation of Ser. No. 199,956, Feb. 22,1994, abandoned.

[30] Foreign Application Priority Data

Feb. 22, 1993 [JP] Japan 5-056455

Sep. 27, 1993 [JP] Japan 5-263024

[51] Int. CI.6 H01L 21/3215

[52] U.S. CI 438/163; 438/595; 438/635;

438/688; 438/768

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205/324, 332; 437/71, 236, 237, 101, 21, 40, 41; 438/151, 158, 163, 165, 166, 308, 595, 635, 688, 765, 784, 768

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(List continued on next page.)

Primary Examiner—Charles L. Bowers, Jr.

Assistant Examiner—Leon Radomsky

Attorney, Agent, or Firm—Sixbey, Friedman, Leedom &

Ferguson, PC; Gerald J. Ferguson, Jr.; Jeffrey L. Costellia

[57] ABSTRACT

A process for fabricating an electronic circuit by oxidizing the surroundings of a metallic interconnection such as of aluminum, tantalum, and titanium, wherein anodic oxidation is effected at a temperature not higher than room temperature, preferably, at 10° C. or lower, and more preferably, at 0° C. or lower. The surface oxidation rate of a metallic interconnection can be maintained constant to provide a surface free of irregularities.

8 Claims, 5 Drawing Sheets

Page 2

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