Jian Zhao, Cameron S. Jorgensen, K. Mahalingam, Cynthia Bowers, Wataru Sugimoto, Kai Ito, Seung Ju Kim, Ruoyu Zhao, Y.-H Xu, Han-Ting Liao, Rajiv K. Kalia, Aiichiro Nakano, Kohei Shimamura, Fuyuki Shimojo, Priya Vashishta, Ajit K. Roy, Ning Ge, Miao Hu, R. Stanley Williams, Qiangfei Xia, Sabyasachi Ganguli, J. Joshua Yang
Nonvolatile memories (NVMs) that operate reliably at high temperatures are essential for electronics in extreme environments. Here, we report graphene (Gra)/HfO x /tungsten (W) memristors that operated reliably up to 700°C, with an ON/OFF current ratio of >10 3 , data retention >50 hours, and endurance >10 9 switching cycles. Transmission electron microscopy revealed substantial W diffusion into the inert platinum (Pt) electrode in conventional Pt/HfO x /W memristors after high-temperature annealing, which was responsible for the thermal failure in conventional devices but not observed in Gra/HfO x /W devices. First-principles calculations attributed the enhanced thermal stability to weaker W adsorption and higher surface diffusion barriers on Gra compared with metals such as Pt. These results underscore the critical role of interfacial engineering and the potential of two-dimensional materials for enabling reliable high-temperature NVM technologies.