Development of at-wavelength metrology for x-ray optics at the ALS

Conference · Fri Jul 09 04:00:00 EDT 2010

OSTI ID:985914

Yashchuk, Valeriy V; Goldberg, Kenneth A; Yuan, Sheng; Celestre, Richard; McKinney, Wayne R; Morrison, Gregory; Warwick, Tony; Padmore, Howard A

The comprehensive realization of the exciting advantages of new third- and forth-generation synchrotron radiation light sources requires concomitant development of reflecting and diffractive x-ray optics capable of micro- and nano-focusing, brightness preservation, and super high resolution. The fabrication, tuning, and alignment of the optics are impossible without adequate metrology instrumentation, methods, and techniques. While the accuracy of ex situ optical metrology at the Advanced Light Source (ALS) has reached a state-of-the-art level, wavefront control on beamlines is often limited by environmental and systematic alignment factors, and inadequate in situ feedback. At ALS beamline 5.3.1, we are developing broadly applicable, high-accuracy, in situ, at-wavelength wavefront measurement techniques to surpass 100-nrad slope measurement accuracy for Kirkpatrick-Baez (KB) mirrors. The at-wavelength methodology we are developing relies on a series of tests with increasing accuracy and sensitivity. Geometric Hartmann tests, performed with a scanning illuminated sub-aperture determine the wavefront slope across the full mirror aperture. Shearing interferometry techniques use coherent illumination and provide higher sensitivity wavefront measurements. Combining these techniques with high precision optical metrology and experimental methods will enable us to provide in situ setting and alignment of bendable x-ray optics to realize diffraction-limited, sub 50 nm focusing at beamlines. We describe here details of the metrology beamline endstation, the x-ray beam diagnostic system, and original experimental techniques that have already allowed us to precisely set a bendable KB mirror to achieve a focused spot size of 150 nm.

• Research Organization: Ernest Orlando Lawrence Berkeley National Laboratory, Berkeley, CA (US)
• Sponsoring Organization: Advanced Light Source Division; Engineering Division; Materials Sciences Division
• DOE Contract Number: AC02-05CH11231
• OSTI ID: 985914
• Report Number(s): LBNL-3726E-Ext-Abs
• Country of Publication: United States
• Language: English

Related Subjects

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY
47 OTHER INSTRUMENTATION
ACCURACY
ADVANCED LIGHT SOURCE
ALIGNMENT
ANL
BRIGHTNESS
FABRICATION
FEEDBACK
FOCUSING
ILLUMINANCE
INTERFEROMETRY
LIGHT SOURCES
MIRRORS
OPTICS
PRESERVATION
RESOLUTION
SENSITIVITY
SYNCHROTRON RADIATION
TUNING
at-wavelength metrology
x-ray optics
bendable mirror
x-ray interferometry