Patent Number: 8,715,891

Title: Mask and pattern forming method

Abstract: According to one embodiment, a mask used with an exposure apparatus is disclosed. The mask includes a main pattern, and a sub-pattern having a dimension smaller than a resolution limit of the exposure apparatus. The sub-pattern is arranged next to the main pattern. The sub-pattern includes a first sub-pattern arranged next to the main pattern, and second sub-patterns contacting the first sub-pattern and arranged along a longitudinal direction of the first sub-pattern. The sub-patterns satisfy a condition of P.ltoreq..lamda./(NA(1+.sigma.0)). Where P is a pitch of the second sub-patterns, NA is a numerical aperture of the exposure apparatus, .lamda. and .sigma.0 are respectively exposure wave length and maximum .sigma. when the main pattern by using the exposure apparatus.

Inventors: Higaki; Tomotaka (Yokohama, JP)

Assignee: Kabushiki Kaisha Toshiba

International Classification: G03F 1/44 (20120101); G03F 1/36 (20120101)

Expiration Date: 5/06/12018