Temperature and Polarization Performance of EUV Silicon Photodiodes

The performance characteristics of a silicon photodiode (type AXUV100) were determined using the beamline X24C at the National Synchrotron Light Source. The diode sensitivity was measured in the temperature range of −92° C to +41° C and in the wavelength region of 3.0 nm to 88.2 nm. This work is important for understanding variations of the diode sensitivity in environments that are colder or hotter than ambient room temperature, such as on a spacecraft or under intense synchrotron or laser irradiation. In addition, the sensitivity of a AVUV100 diode with a multilayer interference coating was measured as a function of the polarization of the incident radiation and the angle of incidence. The Mo/Si multilayer coating, when operating at an angle of incidence of 45°, was designed to selectively transmit the P polarized radiation for detection by the underlying diode and to efficiently reflect the S polarization. The results demonstrate the ability to accurately measure the polarization of radiation within the reflectance profile of the multilayer centered at 13.5 nm. By optimizing the transmittance and reflectance profiles of the multilayer coating for the desired wavelength range and angle of incidence, this new multilayer‐coated photodiode technique can be used to measure the polarization of incident radiation from solar, astrophysical, synchrotron, or other laboratory sources over a wide range of extreme ultraviolet and soft x‐ray wavelengths.