An epitaxial growth method for forming a high-quality epitaxial growth semiconductor wafer is provided. The method includes forming a single crystalline layer on a single crystalline wafer; forming a mask layer having nano-sized dots on the single crystalline layer; forming a porous buffer layer having nano-sized pores by etching the mask layer and the surface of the single crystalline layer; annealing the porous buffer layer; and forming an epitaxial material layer on the porous buffer layer using an epitaxial growth process.