A method for manufacturing a semiconductor structure is provided. The method may include several operations. A substrate is provided, received or formed, wherein the substrate includes an epitaxial structure in a fin structure of the substrate and a metal gate structure over the fin structure. An insulating layer covering the metal gate structure is formed. A semiconductive material layer is formed over the epitaxial structure and the insulating layer, wherein a first portion of the semiconductive material layer over the epitaxial structure comprises crystalline semiconductive material, and a second portion of the semiconductive material layer over the insulating layer comprises amorphous semiconductive material. The second portion of the semiconductive material layer is removed. A semiconductor structure thereof is also provided.