Electrical bistability studies on Ge1Sb2Te4 thin film devices

Thin amorphous films of Ge₁Sb₂Te₄ (GST) with excess tellurium of 500 nm thickness were studied for Non Volatile Random Access Memory (NVRAM) applications. Thin film devices based on GST were prepared from their respective polycrystalline bulk on ITO coated glass substrates by a thermal evaporation technique. Using voltage-resistance (VR) measurements on Al/GST/ITO/Glass device using voltage sweep mode, confirmed the electrical switching of the material between the amorphous and crystalline states, with a resistance difference of 3 orders and threshold voltage of 2.5 V. Device shows the threshold switching, with current-voltage (IV) measurements.