A Comprehensive Study of Total Ionizing Dose Effect on the Electrical Performance of the GaN MIS-HEMT

In this work, the effect of Total Ionizing Dose (TID) on the performance of GaN on Si MIS-HEMT power devices with in-situ SiN cap layer is investigated. 13 samples were exposed to different accumulated dose (100 krad and 400 krad) of Co
$^{60}~\gamma $
-ray irradiation with two bias conditions (grounded and stressed). The characteristics of the devices after irradiation experiment were evaluated by measuring V
_TH
shift, on-resistance (R
_ON
), and dynamic R
_ON
. A comprehensive study of TID effects are demonstrated in this article to verify different mechanisms and their interactions. Simulations using PHITs were also carried out to further confirm the damages in the epitaxial structure by the accumulated dose.