Phase transition characteristics and device performance of Si-doped Ge₂Sb₂Te₅

The phase transition characteristics and device performance of Si-doped Ge2Sb2Te5 thin films were studied for PRAM application. Si-doped Ge2Sb2Te5 thin films were deposited by the RF-magnetron cosputtering system and phase transition characteristics were analyzed by x-ray diffractometer (XRD), 4-point probe measurement and x-ray photoelectron spectroscopy (XPS). The difference in sheet resistance between amorphous and crystalline states was higher than 104 Ω/□. In the XPS spectrum, Si–Te binding was confirmed. In addition, the positional change of Si was observed. The activation energy for transformation decreased with increasing amount of Si in Si-doped Ge2Sb2Te5. In the aspect of phase change memory device application, the RESET current decreased with increasing amount of Si.