Dynamic thermo-magnetic writing in tunnel junction cells incorporating two GeSbTe thermal barriers

Reducing the writing power is a key issue for downsizing MRAM cells < 100 nm. Writing schemes based on thermally assisted magnetization switching (TAS) have been developed for improved power consumption, and thermal barriers was also proposed to minimize thermal losses. Recently, writing power densities of ~2 mW/mum² were achieved (static, micron-sized junctions) with a GeSbTe TB. Here, TAS in micron-sized junction cells incorporating two TB is demonstrated and the heating power density measured for current pulses down to 10 ns.