Abstract: A semiconductor structure and a fabrication method thereof. The semiconductor structure, includes a substrate; and a work function layer on the substrate, that the work function layer contains aluminum and oxygen elements, the work function layer includes a first surface and a second surface opposite to the first surface, a distance between the first surface and a surface of the substrate is less than a distance between the second surface and the surface of the substrate, and along a direction from the first surface to the second surface, a molar percentage concentration of aluminum atoms in the work function layer decreases, and a molar percentage concentration of oxygen atoms in the work function layer decreases. The semiconductor structure can improve the ability to adjust the threshold voltage of a device, thereby improving the performance of the formed semiconductor structure.

Abstract: A semiconductor structure and a fabrication method thereof. The semiconductor structure, includes a substrate; and a work function layer on the substrate, that the work function layer contains aluminum and oxygen elements, the work function layer includes a first surface and a second surface opposite to the first surface, a distance between the first surface and a surface of the substrate is less than a distance between the second surface and the surface of the substrate, and along a direction from the first surface to the second surface, a molar percentage concentration of aluminum atoms in the work function layer decreases, and a molar percentage concentration of oxygen atoms in the work function layer decreases. The semiconductor structure can improve the ability to adjust the threshold voltage of a device, thereby improving the performance of the formed semiconductor structure.