title: High precision tilt stage as a key element to a universal test mirror for characterization and calibration of slope measuring instruments.
abstract: The ultimate performance of surface slope metrology instrumentation, such as long trace profilers and auto-collimator based deflectometers, is limited by systematic errors that are increased when the entire angular range is used for metrology of significantly curved optics. At the ALS X-Ray Optics Laboratory, in collaboration with the HZB/BESSY-II and PTB (Germany) metrology teams, we are working on a calibration method for deflectometers, based on a concept of a universal test mirror (UTM) [V. V. Yashchuk et al., Proc. SPIE 6704, 67040A (2007)]. Potentially, the UTM method provides high performance calibration and accounts for peculiarities of the optics under test (e.g., slope distribution) and the experimental arrangement (e.g., the distance between the sensor and the optic under test). At the same time, the UTM calibration method is inherently universal, applicable to a variety of optics and experimental arrangements. In this work, we present the results of tests with a key component of the UTM system, a custom high precision tilt stage, which has been recently developed in collaboration with Physik Instrumente, GmbH. The tests have demonstrated high performance of the stage and its capability (after additional calibration) to provide angular calibration of surface slope measuring profilers over the entire instrumental dynamic range with absolute accuracy better than 30 nrad. The details of the stage design and tests are presented. We also discuss the foundation of the UTM method and calibration algorithm, as well as the possible design of a full scale UTM system.
authors.affiliation: Lawerence Berkeley National Laboratory, Advanced Light Source, One Cyclotron Road, Berkeley, California 94720, USA.
authors.forename: Valeriy V
authors.initials: VV
authors.lastname: Yashchuk
authors.affiliation: KLA-Tencor Corp., 1 Technology Drive, Milpitas, California 95035, USA.
authors.forename: Nikolay A
authors.initials: NA
authors.lastname: Artemiev
authors.affiliation: Lawerence Berkeley National Laboratory, Advanced Light Source, One Cyclotron Road, Berkeley, California 94720, USA.
authors.forename: Gary
authors.initials: G
authors.lastname: Centers
authors.affiliation: The École nationale supérieure d'ingénieurs de Caen & Centre de Recherche, 6 Boulevard Maréchal Juin, Caen 14000, France.
authors.forename: Arthur
authors.initials: A
authors.lastname: Chaubard
authors.affiliation: Physikalisch-Technische Bundesanstalt, Bundesallee 100, Braunschweig 38116, Germany.
authors.forename: Ralf D
authors.initials: RD
authors.lastname: Geckeler
authors.affiliation: Lawerence Berkeley National Laboratory, Advanced Light Source, One Cyclotron Road, Berkeley, California 94720, USA.
authors.forename: Ian
authors.initials: I
authors.lastname: Lacey
authors.affiliation: Physik Instrumente (PI) GmbH & Co.KG, Auf der Roemerstrasse 1, Karlsruhe 76228, Germany.
authors.forename: Harry
authors.initials: H
authors.lastname: Marth
authors.affiliation: Diablo Valley College, 321 Golf Club Rd, Pleasant Hill, California 94523, USA.
authors.forename: Wayne R
authors.initials: WR
authors.lastname: McKinney
authors.affiliation: Helmholtz Zentrum Berlin, BESSY-II, Institute for Nanometre Optics and Technology, Albert-Einstein-Str. 15, Berlin 12489, Germany.
authors.forename: Tino
authors.initials: T
authors.lastname: Noll
authors.affiliation: Helmholtz Zentrum Berlin, BESSY-II, Institute for Nanometre Optics and Technology, Albert-Einstein-Str. 15, Berlin 12489, Germany.
authors.forename: Frank
authors.initials: F
authors.lastname: Siewert
authors.affiliation: Physik Instrumente (PI) GmbH & Co.KG, Auf der Roemerstrasse 1, Karlsruhe 76228, Germany.
authors.forename: Mathias
authors.initials: M
authors.lastname: Winter
authors.affiliation: Helmholtz Zentrum Berlin, BESSY-II, Institute for Nanometre Optics and Technology, Albert-Einstein-Str. 15, Berlin 12489, Germany.
authors.forename: Thomas
authors.initials: T
authors.lastname: Zeschke