Mask for photolithography, method for fabricating the same and method for manufacturing semiconductor device using the mask

A method of manufacturing a semiconductor device comprising:

• providing a wafer comprising an object layer;
• coating a photoresist layer on the object layer;
• exposing the photoresist layer to a light source through a photo mask;
• developing the photoresist layer to form a photoresist pattern;
• and
• etching the object layer to form an object layer pattern using the photoresist pattern as an etch mask,
• wherein the photo mask comprises,
• a substrate;
• and
• a main pattern and a sub pattern formed on the substrate,
• wherein the main pattern comprises a partially transparent phase shift material and the sub pattern comprises an opaque material, and the sub pattern has small enough dimensions so that it is insufficient to fully block light at any location on the photoresist layer under the sub pattern.

A method of manufacturing a semiconductor device comprising:

• coating a photoresist layer on a wafer substrate;
• exposing the photoresist layer to a light source through a photo mask;
• developing the photoresist layer to form a photoresist pattern;
• and
• performing an etch corresponding to the photoresist pattern,
• wherein the photo mask comprises,
• a photo mask substrate;
• a partially transparent pattern formed on the photo mask substrate;
• and
• a sub resolution assist feature formed on the photo mask substrate,
• wherein the partially transparent pattern comprises a phase shift material and the sub resolution assist feature comprises an opaque material,
• wherein the sub resolution assist feature has small enough dimensions so that the exposing light bends around the sub resolution assist feature and exposes the photoresist layer under the sub resolution assist feature from a first location directly under a first edge of the sub resolution assist feature to a second location directly under a second edge of the resolution assist feature that is opposite to the first edge.