A phase change random access memory includes a semiconductor substrate having a bottom electrode formed over the semiconductor substrate; and a phase change layer formed over the bottom electrode. The phase change layer a first phase change layer formed over the bottom electrode and including at least one of a first element, a second element, and a third element; and a second phase change layer formed over a surface of the first phase change layer and formed of the first element to prevent an area of the first phase change layer from increasing through diffusion.