Semiconductor device and forming method thereof

A semiconductor device and a method of forming the same are provided. The method includes forming a first fin and a second fin over a substrate. The method includes forming a first dummy gate structure across the first fin and the second fin, wherein the first dummy gate structure includes a first dummy gate dielectric and a first dummy gate disposed over the first dummy gate dielectric. The method includes replacing a portion of the first dummy gate with a gate isolation structure, wherein the portion of the first dummy gate is disposed over the second fin. The method includes removing the first dummy gate. The method includes removing a first portion of the first dummy gate dielectric around the first fin while maintaining a second portion of the first dummy gate dielectric around the second fin intact. The method includes forming a gate feature across the first fin and the second fin, wherein the gate isolation structure intersects the gate feature. 提供一种半导体装置及其形成方法。方法包含在基底上方形成第一鳍状物以及第二鳍状物。方法包含形成横跨第一鳍状物以及第二