| 摘要 |
<p>A semiconductor device comprises: a substrate; a middle layer over the substrate; a first nitride semiconductor layer over the middle layer; and a second nitride semiconductor layer disposed over the first nitride semiconductor layer, and contacting the first nitride semiconductor layer to form a heterogeneous junction interface, wherein the middle layer comprises: a plurality of superlattice unit layer groups; and GaN, and comprises insertion layers disposed between the superlattice unit layer groups, wherein each of the superlattice unit layer groups comprises a plurality of double layers, and each of the double layers comprises: a first superlattice layer including Al_xGa_1-xN (where 0 <= x <= 1); and a second superlattice layer disposed on the first superlattice layer, and including Al_yGa_1-yN (where 0 <= y <= 1, x≠y).</p> |
