The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Mar. 16, 1999
Filed:
May. 17, 1995
Young Jin Song, Chungcheongbuk-do, KR;
LG Semicon Co., Ltd., Chungcheongbuk-Do, KR;
Abstract
A multistage phase shift mask includes a light transmissive substrate having light shielding regions and light transmissive regions. A shielding layer is disposed on the shielding regions of the substrate and a phase shifter layer extends over the light transmissive regions between a pair of the shielding regions. A first etched portion on the substrate is adjacent to the phase shifter layer that contacts with the substrate and a second etched portion on the substrate is between the phase shifter layer and the first etched portion of the substrate. The second etched portion consists of a gradual concave slope allowing a phase shift from approximately 0 to 180 degrees.