Performance report of a substrate-removed InGaAs sensor for the JASMINE mission

We conducted the evaluation testing of the InGaAs image sensor for the future JASMINE mission. The InGaAs image sensor, which is manufactured by Hamamatsu Photonics K.K., has been updated with substrate removal to avoid fluorescence caused by cosmic rays. We introduce preliminary performance reports of the 128×128 arrayed small prototype at 170K, assuming space use, including dark current and relative quantum efficiency in the near-infrared. Notably, we confirmed that fluorescence is significantly mitigated with an exposure of about 10 minutes. Furthermore, the relative quantum efficiency in the visible wavelength is enhanced compared to previous evaluations in the literature. These results provide a good configuration for the test of the sensor for deployment and play an important role in the future development of infrared astronomical instruments.