| 摘要 |
PROBLEM TO BE SOLVED: To obtain desired electrical characteristics by preventing dishing and making the thickness of copper films in a groove wiring equal to each other by forming another planarizing pattern in a wiring pattern section. SOLUTION: After a Cu film 106 is electroplated, a positive photoresist having a film thickness of 1μm is applied to the surface of the film 106 as a photosensitive material 107. A KrF excimer laser beam 110 is irradiated upon the upper part of groove wiring, and the photosensitive material is developed with an alkaline solution. Only in the groove wiring section, a Cu film 111, having a thickness of 0.4μm corresponding to a step 109, is deposited by performing a second plating process for about 50 seconds under the condition of 20 mA/cm2. Through this plating process, a pattern formed of the Cu film 111 is grown on the groove pattern, having a width which is broader than a prescribed value. When the second electroplating is performed, a flat Cu film is no longer able to be formed, because Cu films grow from the side walls of the groove wiring and thick Cu films of the sidewalls. After the second electroplating, the photoresist is removed. Consequently, a flat Cu film having no step is formed before chemical and mechanical polishing.
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