Phase transformation behaviors of Si O2 doped Ge2 Sb2 Te5 films for application in phase change random access memory

The improvement in the phase change characteristics of Ge2 Sb2 Te5 (GST) films for phase change random access memory applications was investigated by doping the GST films with Si O2 using cosputtering at room temperature. As the sputtering power of Si O2 increased from 0 to 150 W, the activation energy for crystallization increased from 2.1±0.2 to 3.1±0.15 eV. Si O2 inhibited the crystallization of the amorphous GST films, which improved the long term stability of the metastable amorphous phase. The melting point decreased with increasing concentration of Si O2, which reduced the power consumption as well as the reset current.