Method for manufacturing semiconductor structure

A method for manufacturing a semiconductor structure, comprising:

• forming a masking layer over a substrate;
• forming a photoresist pattern over the masking layer;
• patterning the masking layer through the photoresist pattern;
• treating the photoresist pattern to diminish a width of the photoresist pattern;
• patterning the masking layer through the photoresist pattern;
• removing the photoresist pattern;
• etching the semiconductor substrate through the masking layer to form a fin structure;
• forming an isolation structure around the fin structure;
• and
• forming a gate structure across the fin structure.

A method for manufacturing a semiconductor structure, comprising:

• forming a first oxide layer over a substrate;
• forming a first masking layer over the first oxide layer;
• forming a second masking layer over the first masking layer;
• forming a photoresist pattern over the second masking layer;
• patterning the second masking layer through the photoresist pattern;
• performing a trimming process to the photoresist pattern so that a width of the photoresist pattern before the trimming process is greater than a width of the photoresist pattern after the trimming process;
• patterning the second masking layer, the first masking layer, and the first oxide layer through the photoresist pattern after performing the trimming process;
• patterning the semiconductor substrate through the second masking layer and the first masking layer to form a fin structure;
• and
• forming a gate structure over the fin structure.