Abstract
Some embodiments of the present disclosure provide a semiconductor device and a manufacturing method thereof. The semiconductor device includes: a semiconductor heterostructure layer and a conductivestructure. A semiconductor heterostructure (herterostructure) layer, which includes alternating first and second semiconductor material layers, wherein a two-dimensional electron gas can be generatedbetween each adjacent first and second semiconductor material layers (2DEG). The conductive structure includes a plurality of conductive fingers extending from the surface of the semiconductor heterostructure layer into the semiconductor heterostructure layer, wherein the plurality of conductive fingers are arranged along a first direction substantially parallel to the surface, and the length of the plurality of conductive fingers increases along the first direction, so that the ends of each conductive finger are respectively located in the first semiconductor material layer of different depths and contact the 2DEG.