Material design for Ge₂Sb₂Te₅ phase-change material with thermal stability and lattice distortion

To overcome the reliability issue of phase-change memory, the development of stable phase-change materials is extremely important. In this study, we analyze 13 dopants for Ge₂Sb₂Te₅ (GST)based on two criteria: i)the change in thermal stability by doping and ii)a lattice distortion. After doping the elements, 11 elements showed a negative doping formation energy compared with pure GST. The angular distortion of the Zn dopant is the largest. The hole carrier decreases, and the electrical resistance increases through Zn-doping in GST. The increased resistance of the material can lead to low power consumption with a high energy effectiveness.