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:
Jun. 21, 2016
Filed:
Jan. 24, 2014
International Business Machines Corporation, Armonk, NY (US);
Toppan Printing Co., Ltd., Tokyo, JP;
Brian N. Caldwell, Meridian, ID (US);
Yuki Fujita, Tokyo, JP;
Raymond W. Jeffer, South Burlington, VT (US);
James P. Levin, South Burlington, VT (US);
Joseph L. Malenfant, Jr., Colchester, VT (US);
Steven C. Nash, Essex Junction, VT (US);
International Business Machines Corporation, Armonk, NY (US);
Toppan Printing CO., LTD., Tokyo, JP;
Abstract
Aspects of the present invention relate to a test photomask and a method for evaluating critical dimension changes in the test photomask. Various embodiments include a test photomask. The test photomask includes a plurality of cells having a varied density pattern. The plurality of cells include a first group of cells arranged along a first line, the first group of cells having a first combined density ratio. The plurality of cells also include a second group of cells arranged along a second line, the second group of cells having a second combined density ratio. In the plurality of cells, the second combined density ratio for the second group of cells is equal to the first combined density ratio of the first group of cells. The varied density pattern is configured to substantially neutralize fogging effects.