Method for manufacturing micro structure
AssigneeFujitsu Semiconductor Limited
InventorHiroshi Morioka
Life of this patent
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Abstract
A method for forming a pattern includes the steps of: (a) preparing a lower hard mask layer and an upper hard mask layer stacked on an etching target film; (b) forming a resist pattern above the upper hard mask layer; (c) etching the upper hard mask film by using the resist pattern as an etching mask to form an upper hard mask; (d) after the step (c), removing the resist pattern; (e) after the step (d), thinning the upper hard mask by etching; (f) etching the lower hard mask film by using the thinned upper hard mask as an etching mask to form a lower hard mask; and (g) etching the etching target film by using the upper hard mask and the lower hard mask as an etching mask. The method for forming a pattern can etch a fine pattern with good yield.
Claims20
A method for forming a pattern comprising the steps of:
- (a) forming a lower hard mask layer and an upper hard mask layer stacked on an etching object including an etching target film at an uppermost level;
- (b) forming a resist pattern above said upper hard mask layer;
- (c) etching said upper hard mask layer by using said resist pattern as an etching mask to form an upper hard mask;
- (d) after said step (c), removing said resist pattern;
- (e) after said step (d), thinning said upper hard mask by etching;
- (f) etching said lower hard mask layer by using said thinned upper hard mask as an etching mask to form a lower hard mask;
- and
- (g) etching said etching target film by using both said upper hard mask and said lower hard mask as an etching mask.
Dependencies are inferred from the claim text.