Semiconductor epitaxial structure

The invention provides a semiconductor epitaxial structure. The semiconductor epitaxial structure comprises a silicon carbide substrate, a nucleating layer, a gallium nitride buffer layer and a stacking structure, the nucleating layer is formed on the silicon carbide substrate, the gallium nitride buffer layer is arranged on the nucleating layer, and the stacking structure is formed between the nucleating layer and the gallium nitride buffer layer. The stacking structure comprises a plurality of silicon nitride (SiNx) layers and a plurality of aluminum gallium nitride (Al < x > Ga < 1-x > N) layers which are alternately stacked, and a first layer in the plurality of silicon nitride layers is in direct contact with the nucleating layer. 本发明提供一种半导体外延结构，包括碳化硅基板、成核层、氮化镓缓冲层与堆叠结构。成核层形成于所述碳化硅基板上，氮化镓缓冲层设置于所述成核层上，堆叠结构则形成于所述成核层与所述氮化镓缓冲层之间。所述堆叠结构包括：交替堆叠的多层氮化硅(SiNx)层与多层氮化铝镓(AlxGa1-xN)层，其中所述多层氮化硅层中的第一层与所述成核层直接接触。