Characterization of groove density variation of VLS gratings with ALS XROL LTP-II in different operation modes
- Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)
The long trace profiler, LTP-II, available at the Advanced Light Source (ALS) X-ray Optics Laboratory (XROL), was recently upgraded by replacing a multimode diode laser light source with a single-mode, wavelength-stabilized, fibercoupled diode laser system. The upgrade enables us to reliably characterize the lateral variation of groove density of variable-line-spacing (VLS) x-ray diffraction gratings. Here, we discuss the LTP-II performance with an example of measurements with a VLS grating with the groove density at the grating center of 300 lines/mm. For the measurements, we use the LTP-II in two different operation arrangements, the single Gaussian beam and the pencil beam interferometer arrangements. For each operation arrangement, we apply two data processing algorithms: with calculating the centroid position and with determining the position of a characteristic features of the detected beam intensity distributions. Additionally, we discuss the observed strong correlation between the LTP-II modes of operation and the resulted (extracted) groove density variations. We also speculate on possible origin of the correlation.
- Research Organization:
- Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States)
- Sponsoring Organization:
- USDOE Office of Science (SC), Basic Energy Sciences (BES). Materials Sciences & Engineering Division
- Grant/Contract Number:
- AC02-05CH11231
- OSTI ID:
- 1887192
- Journal Information:
- Proceedings of SPIE (Online), Vol. 11492; Conference: SPIE Optical Engineering + Applications, Held Virtually, 2020; Related Information: Advances in Metrology for X-Ray and EUV Optics IX; ISSN 1996-756X
- Publisher:
- SPIECopyright Statement
- Country of Publication:
- United States
- Language:
- English
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