Gamma Radiation Effects on HfO 2 -based RRAM Devices

In this work, the effect of 60Co gamma radiation on the electrical properties of TiN/Ti/HfO 2 /W RRAM devices is investigated through systematic and extensive measurements of biased and unbiased devices during irradiation. For this purpose, first an experiment has been carried out in fresh devices in order to verify that gamma radiation did not permanently damage the HfO 2 after several cumulative radiation doses. Then, the resistive switching behavior of the RRAMs has been assessed by comparing the performance of the devices prior and after irradiation up to a total dose of 22 Mrad(Si). Furthermore, data retention experiments have been carried out by in-situ measuring the device resistance under radiation exposure, for both the low and the high resistance states up to a dose of 7.9 Mrad(Si). The results clearly show that the electrical response of HfO 2 -based RRAM devices prior and after the formation of an oxygen deficient conductive filament is not significantly affected by ionizing radiation and its corresponding damage. The observed radiation hardness of the devices against gamma radiation in the studied doses is a promising result to extend the application of the HfO 2 -based RRAM technology to the space industry and other harsh environments.