The present invention provides a phase change memory cell comprising (Ge.sub.ASb.sub.BTe.sub.C).sub.1-X(R.sub.aS.sub.bTe.sub.C).sub.X solid solution, the solid solution being formed from a Ge--Sb--Te based alloy and a ternary metal alloy R--S--Te sharing same crystal structure as the Ge--Sb--Te based alloy. A nonvolatile phase change memory cell in accordance with the present invention provides many advantages such as high speed, high data retention, and multi-bit operation.