Objective At present, vacuum ultraviolet space detection technology is widely used in a number of scientific and technological projects in China, such as extreme ultraviolet lithography machine, Fengyun satellite, Mars exploration plan, Kuafu plan, etc. The national demand for calibration technology for related vacuum ultraviolet detection systems is also becoming more and more urgent. As one of the six international key comparisons in the field of optical metrology, spectral responsivity reflects the response ability of detectors to different wavelengths of light, and the research on vacuum ultraviolet spectral responsivity calibration technology plays a vital role in the development of vacuum ultraviolet detection technology. The domestic spectral responsivity calibration technology cannot fully cover the 10-200 nm band. Therefore, in this paper, we will carry out the research on the vacuum ultraviolet spectral responsivity calibration device based on synchrotron radiation source to realize the spectral responsivity calibration of the vacuum ultraviolet 10-200 nm band, and control the spectral responsivity calibration uncertainty within 10%.

Methods  A vacuum ultraviolet spectral responsivity calibration device based on synchrotron radiation was constructed. The light source is a synchrotron radiation source located in the National Synchrotron Radiation Laboratory in Hefei, and the detector uses a silicon photodiode with a model of AXUV100G, and the calibration process uses the comparison method to calibrate the calibration of the calibrated detector. The wavelength is calibrated using a gas ionization chamber prior to calibration, and the Gaussian harmonics are filtered using a gas filter cell during calibration.

Results and Discussions The uncertainty of the synchrotron radiation-based spectral responsivity calibration device was analyzed and verified. The uncertainty component introduced by the measurement repeatability, the uncertainty component introduced by the vacuum ultraviolet beamline instability of the synchrotron radiation source, the uncertainty component introduced by the standard detector, and the uncertainty component introduced by the data acquisition equipment were introduced respectively, and the relative extended uncertainty of the calibration device was calculated to meet the requirements of 10-35 nm: U=2.0% (k=2), 35-130 nm: U=10% (k=2), 130-200 nm:U=3.0%(k=2).

Conclusions A set of vacuum ultraviolet spectral responsivity calibration device based on synchrotron radiation source was established, and the calibration wavelength range covered 10-200 nm, which effectively made up for the gap of relevant calibration bands in China. The gas ionization chamber is used to self-calibrate its own wavelength before calibration, and the Gaussian harmonics are suppressed using a gas filter cell during the test. It has a wide range of application and promotion value in the field of space exploration. In the future, it is planned to use the self-developed cryogenic radiometer to realize the traceability of relevant bands, laying the foundation for getting rid of foreign monopoly.