- 专利标题: Evaluation method of defect size of photomask blank, selection method, and manufacturing method
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申请号: US14921076申请日: 2015-10-23
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公开(公告)号: US09772551B2公开(公告)日: 2017-09-26
- 发明人: Tsuneo Terasawa , Takahiro Kishita , Daisuke Iwai , Hiroshi Fukuda , Atsushi Yokohata
- 申请人: SHIN-ETSU CHEMICAL CO., LTD.
- 申请人地址: JP Tokyo
- 专利权人: SHIN-ETSU CHEMICAL CO., LTD.
- 当前专利权人: SHIN-ETSU CHEMICAL CO., LTD.
- 当前专利权人地址: JP Tokyo
- 代理机构: Birch, Stewart, Kolasch & Birch, LLP
- 优先权: JP2014-217386 20141024
- 主分类号: G03F1/84
- IPC分类号: G03F1/84 ; G03F1/50 ; G01N21/88 ; G01N21/956 ; G01N21/95
摘要:
The defect size of a photomask blank is evaluated. An inspection-target photomask blank is irradiated with inspection light and reflected light of the region of the inspection-target photomask blank irradiated with the inspection light is collected through an objective lens of an inspection optical system as a magnified image of the region. Then, an intensity change part in the light intensity distribution profile of the magnified image is identified. Next, a difference in the light intensity of the intensity change part is obtained and the width of the intensity change part is obtained as the apparent width of the defect. Then, the width of the defect is calculated on the basis of a predetermined conversion expression showing the relationship among the difference in the light intensity, the apparent width of the defect, and the actual width of the defect, and the width of the defect is estimated.