Phase change and optical band gap behavior of Ge-Te-Ga thin films prepared by thermal evaporation

► Ge11.4Te86.4Ga2.2 thin film has good thermal stability. ► Ge11.4Te86.4Ga2.2 thin film has high crystalline resistance. ► Ge11.4Te86.4Ga2.2 thin film has wide optical band gap. ► Ge11.4Te86.4Ga2.2 has a high amorphous/crystalline resistance ratio of about 105.