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JPH03156458A Expired / Lapsed JP ⏱️ 0.0 years remaining

Photomask

Assignee: Fujitsu Ltd
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Filing: 1989-11-14
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Granted: —
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Expires: 2009-11-14
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Abstract

Abstract PURPOSE:To obtain a flaw-free photomask having no lacking on a pattern by superposing a pair of glass substrates having respective patterns which are mutually inversely symmetrical so that respective pattern faces coincide with each other. CONSTITUTION:Chrome film patterns 2a, 2b on a pair of glass substrates 1a, 1b are formed so as to be inversely symmetrical and are stuck to each other so that respective patterns 2a, 2b are superposed to each other. In this case, the positions of pin holes 3a, 3b do not generally coincide with each other and the pin hole 3a of one glass substrate 1a is covered with the chrome film pattern 2b of the other glass substrate 1b. Consequently, a photomask having no lacking on the pattern can be obtained.

Inventors

  • 👤 Atsushi Takizawa
  • 👤 滝沢 厚嗣
  • 👤 Masashi Miura
  • 👤 三浦 昌司

Bibliographic Details

Application Number —
Jurisdiction JP
Data Source google_patents
Last Synchronized 2026-10-30 16:56
CPC Classifications
—

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