The influence of Ti dopant in the titanium-doped Ge₂Sb₂Te₅ film upon its optical and structural characteristics has been investigated by spectroscopic ellipsometry and x-ray diffraction. Temperature-dependent resistance tests have further revealed that Ti-doped Ge₂Sb₂Te₅ films have better thermal stability than undoped one. Based on the Arrhenius extrapolation results from data retention tests, the endurance temperature corresponding to 10-year data retention of a Ti-doped Ge₂Sb₂Te₅ cell is higher than that of a common Ge₂Sb₂Te₅ cell without dopant. All these experimental results have confirmed that the Ti-doped Ge₂Sb₂Te₅ films are more suitable for the application in phase-change random access memory.