Semiconductor structure and manufacturing method thereof
A semiconductor structure includes a silicon carbide substrate, a silicon carbide buffer layer, and an epitaxial layer. The silicon carbide buffer layer is disposed on the silicon carbide substrate. The epitaxial layer is disposed on the silicon carbide buffer layer, in which a molar ratio of carbon to silicon atoms in the silicon carbide buffer layer gradually increases along a direction from the silicon carbide substrate to the epitaxial layer.
1 . A semiconductor structure, comprising:
a silicon carbide substrate;
a silicon carbide buffer layer disposed on the silicon carbide substrate; and
an epitaxial layer disposed on the silicon carbide buffer layer, wherein a molar ratio of carbon to silicon atoms in the silicon carbide buffer layer gradually increases along a direction from the silicon carbide substrate to the epitaxial layer.
2 . The semiconductor structure of claim 1 , wherein a doping concentration of the silicon carbide buffer layer gradually decreases along a direction from the silicon carbide substrate to the epitaxial layer.
3 . The semiconductor structure of claim 1 , wherein a centerline average roughness of the silicon carbide buffer layer gradually decreases along a direction from the silicon carbide substrate to the epitaxial layer.
4 . The semiconductor structure of claim 1 , wherein a thickness of the silicon carbide buffer layer is 0.5 μm to 3.0 μm.