(19)
(11)EP 2 063 321 A3

(12)EUROPEAN PATENT APPLICATION

(88)Date of publication A3:
12.07.2017 Bulletin 2017/28

(43)Date of publication A2:
27.05.2009 Bulletin 2009/22

(21)Application number: 08169443.2

(22)Date of filing:  19.11.2008
(51)Int. Cl.: 
G03F 7/20  (2006.01)
(84)Designated Contracting States:
AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MT NL NO PL PT RO SE SI SK TR
Designated Extension States:
AL BA MK RS

(30)Priority: 20.11.2007 US 996506 P

(71)Applicant: ASML Netherlands BV
5504 DR Veldhoven (NL)

(72)Inventors:
  • Hofmans, Gerardus Carolus Johannus
    5628 AH, Eindhoven (NL)
  • Geraets, Hubertus Antonius
    BE-2370, Arendonk (BE)
  • Zellenrath, Mark
    5508 TD, Veldhoven (NL)
  • Magnusson, Sven Gunnar Krister
    5503 HG, Veldhoven (NL)

(74)Representative: van Os, Lodewijk Hubertus et al
ASML Netherlands B.V. Corporate Intellectual Property P.O. Box 324
5500 AH Veldhoven
5500 AH Veldhoven (NL)

  


(54)Method of measuring focus of a lithographic projection apparatus


(57) A method of measuring focus of a lithographie projection apparatus includes exposure of a photoresist covered test substrate with a plurality of verification fields. Each of the verification fields includes a plurality of verification markers, and the verification fields are exposed using a predetermined focus offset FO. After developing, an alignment offset for each of the verification markers is measured and translated into defocus data using a transposed focal curve. The method according to the invention results in a focus-versus alignment shift sensitivity some 50 times higher (typically dX,Y/dZ = 20) than the present LVT.