Semiconductor structure and forming method thereof

The invention discloses a semiconductor structure and a forming method thereof. The gate dielectric layer is positioned on the substrate; the barrier layer is positioned on the gate dielectric layer; the work function layer is located on the barrier layer, and the oxidation rate of the barrier layer is smaller than that of the work function layer. The performance of the semiconductor structure is improved. 一种半导体结构及其形成方法，结构包括：衬底；位于衬底上的栅介质层；位于栅介质层上的阻挡层；位于阻挡层上的功函数层，所述阻挡层的氧化速率小于所述功函数层的氧化速率。所述半导体结构的性能得到提升。