Semiconductor structure and method for forming same

Abstract

A semiconductor structure and a method for forming same are provided, the forming method including: providing a base including a plurality of adjacent device unit regions, an initial device gate structure spanning a plurality of device unit regions being formed on the base; etching a portion of the initial device gate structure in thickness at a junction between the adjacent device unit regions to form a top opening; forming a spacer layer on a side wall of the top opening; etching a remainder of the initial device gate structure exposed from the spacer layer, and forming a bottom opening exposed from the base within the remainder of the initial device gate structure, the remainder of the initial device gate structure being used as a device gate structure; and forming an isolation structure within the top opening and the bottom opening. The spacer layer is configured to adjust a width of the bottom opening, so that the width of the bottom opening is less than a width of the top opening. Therefore, the width of the top opening can be increased properly to enlarge a process window in which the top opening is formed, thereby better implementing isolation between the adjacent device unit regions and improving integrity of the device gate structure, further helping improve performance of a transistor.