In this work, we evaluated the structural, electrical and optical properties of carbon-doped Ge8Sb2Te11 thin films. In a previous work, GeSbTe alloys were doped with different materials in an attempt to improve the thermal stability. Ge8Sb2Te11 and carbon-doped Ge8Sb2Te11 films of 250 nm in thickness were deposited on p-type Si (100) and glass substrates by using a RF magnetron reactive co-sputtering system at room temperature. The fabricated films were annealed in a furnance in the 0 ~ 400°C temperature range. The structural properties were analyzed by using X-ray diffraction (XRD), and the result showed that the carbon-doped Ge8Sb2Te11 had a face-centeredcubic (fcc) crystalline structure and an increased crystallization temperature (Tc). An increase in the Tc leads to thermal stability in the amorphous state. The optical properties were analyzed by using an UV-Vis-IR spectrophotometer, and the result showed an increase in the optical-energy band gap (Eop) in the crystalline materials and an increase in the Eop difference (ΔEop), which is a good effect for reducing the noise in the memory device. The electrical properties were analyzed by using a 4-point probe, which showed an increase in the sheet resistance (Rs) in the amorphous state and the crystalline state, which means a reduced programming current in the memory device.