Radiation-induced effects on the RIGEL ASIC

This paper describes the radiation tests performed on the RIGEL, the Application-Specific Integrated Circuit (ASIC) designed within the scope of the PixDD project, whose goal is the production of a multi-pixel silicon based detector system to be placed at the focal plane of X-ray optics on board space astronomy missions. Carried out at the RADiation Effects Facility of the University of Jyvaskyla (Finland), the campaign aimed at studying the response of the ASIC to radiation damage, in the form of both Total Ionising Dose and Single Event Effects, especially latch-ups and bit upsets. Experimental results were then combined with simulations of the space environment for a low-inclination equatorial orbit and for a Sun-synchronous orbit. The analysis shows that the device under study may be safely operated on an equatorial orbit without any circuitry to protect it from transient radiation phenomena, whereas the need of such a precaution is necessary in the case of a Sun-synchronous orbit. According to the experimental results, the degradation due to Total Ionising Dose, measured in terms of Equivalent Noise Charge, stays below 10% up to 34 krad, implying that it can be managed or neglected altogether for the simulated orbits.