Semiconductor structure and forming method thereof

A method for forming a semiconductor structure comprises the steps that a substrate and a plurality of initial fin structures which are located on the substrate and are separated from one another are formed, and each initial fin structure comprises a second fin, a first fin located on the second fin and an initial middle layer located between the first fin and the second fin; performing oxidation treatment on the initial intermediate layer until the initial intermediate layer is partially or completely oxidized, and forming a blocking structure between the first fin and the second fin to form a fin structure; and after the blocking structure is formed, forming a plurality of gate structures across the surface of the first fin on the substrate. Therefore, the performance of the semiconductor structure is improved. 一种半导体结构的形成方法，包括：形成衬底、以及若干位于所述衬底上且相互分立的初始鳍部结构，每个所述初始鳍部结构包括第二鳍、位于第二鳍上的第一鳍、以及位于所述第一鳍和第二鳍之间的初始中间层；对所述初始中间层进行氧化处理，直至所述初始中间层部分或全部被氧化，在所述第一鳍和第二鳍之间形成阻挡结构，以形成鳍部结构；在形成所述阻挡结构之后，在所述衬底上形成若干横跨所述第一鳍表面的栅极结构。从而，提高了半导