Patent ID: 7829246

Claim:
A method of forming a pattern, in which an interconnect pattern including a plurality of straight lines that are arranged in parallel is formed in a photoresist film on or over a wafer by exposing thereof to light through a phase shifting mask, said phase shifting mask having interconnect apertures that extend toward a predetermined direction and are arranged in parallel, and said phase shifting mask also being configured that transmitted lights of two different phases are alternately assigned in the interconnect apertures, said method comprising: providing a different phase aperture in a longitudinal external side of each corresponding one of said interconnect apertures in said phase shifting mask, said different phase aperture providing a phase of transmitted light that is different from a phase of light through the corresponding one of said interconnect apertures; transferring a basic pattern in a photoresist film via an exposure by using said phase shifting mask, said basic pattern containing said interconnect pattern and a temporary pattern formed from an end of said interconnect pattern toward a longitudinal external side thereof; and transferring a temporary pattern in a photoresist film for removing said temporary pattern from said basic pattern via an exposure by using a trim mask.