Exposure mask and method of manufacture thereof

U.S. Patent Number: 5391441

Abstract: Disclosed are phase-shifting masks wherein restriction of light transmission at edges of phase-shifting patterns (e.g., at an edge where a 180.degree. phase-shifting pattern ends on a light transmission region) is avoided, and methods of making such masks. The region of the transparent pattern of the mask, under the edge of the phase-shifting pattern, is made wider than that of the transparent pattern in other regions; moreover, an additional phase-shifting layer is provided at the edge of the phase-shifting pattern, the additional phase-shifting layer having a phase-shift preferably of less than 90.degree., to avoid a 180.degree. phase shift at the edge. Also disclosed is a phase-shifting mask having repaired defects, and a method for repairing defects in phase-shifting masks, using an additional phase-shifting layer.

Inventors: Imai; Akira (Hachioji, JP), Hasegawa; Norio (Hinodemachi, JP)

Assignee: Hitachi, Ltd. (Tokyo, JP)

Application Number: 08/019,889

Issued: 1995-02-21

Expired: 2007-02-21

Classes: 430/5 ; 430/323; 430/324

Field of search: 430/5,323,324

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