Note: Effect of photodiode aluminum cathode frame on spectral sensitivity in the soft x-ray energy band
- Department of Physics, University of Wisconsin–Madison, Madison, Wisconsin 53706 (United States)
- Consorzio RFX, Associazione Euratom-ENEA per la Fusione, Padova (Italy)
Silicon photodiodes used for soft x-ray detection typically have a thin metal electrode partially covering the active area of the photodiode, which subtly alters the spectral sensitivity of the photodiode. As a specific example, AXUV4BST photodiodes from International Radiation Detectors have a 1.0 μm thick aluminum frame covering 19% of the active area of the photodiode, which attenuates the measured x-ray signal below ∼6 keV. This effect has a small systematic impact on the electron temperature calculated from measurements of soft x-ray bremsstrahlung emission from a high-temperature plasma. Although the systematic error introduced by the aluminum frame is only a few percent in typical experimental conditions on the Madison Symmetric Torus, it may be more significant for other instruments that use similar detectors.
- OSTI ID:
- 22314465
- Journal Information:
- Review of Scientific Instruments, Vol. 85, Issue 9; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA); ISSN 0034-6748
- Country of Publication:
- United States
- Language:
- English
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