Stripe structures and fabrication method thereof

A method for fabricating stripe structures, comprising:

• providing a substrate;
• forming a to-be-etched layer on the substrate;
• forming a first stripe made of a hard mask pattern on the to-be-etched layer and exposing the to-be-etched layer;
• forming a photoresist pattern on the exposed to-be-etched layer and on the first stripe made of the hard mask pattern, the photoresist pattern including a stripe opening formed on the first stripe and perpendicular to a length direction of the first stripe;
• forming a polymer layer on a top surface and side surfaces of the photoresist pattern to reduce a width of the stripe opening;
• etching through the first stripe made of the hard mask pattern using the photoresist pattern having the polymer layer as an etching mask to form second stripes made of the hard mask pattern;
• and
• forming the stripe structures by etching the to-be-etched layer using the second stripes made of the hard mask pattern as an etching mask to remove a portion of the to-be-etched layer to expose a surface portion of the substrate.