A phase change material, a PRAM including the same, and methods of manufacturing and operating the same are provided. Insulating impurities may be uniformly distributed over an entire or partial region of the phase change material. The PRAM may include a phase change layer including the phase change material. The insulating impurity content of the phase change material may be 0.1 to 10% (inclusive) the volume of the phase change material. The insulating impurity content of the phase change material may be adjusted by controlling the power applied to a target including the insulating impurities.