High electron mobility transistor

A high electron mobility transistor includes a substrate, a compound semiconductor stacking layer, a cap layer, a gate electrode, a source electrode, a drain electrode, and a buried through electrode and/or a conductive structure. The substrate has an active area. The semiconductor layer includes a buffer layer, a high resistance layer, a channel layer and a barrier layer disposed on the substrate in sequence. The cap layer is disposed on the compound semiconductor stacking layer. The gate electrode is disposed on the cap layer and extends along a first direction. The source electrode and the drain electrode are disposed on the compound semiconductor stacking layer, on two sides of the gate electrode, respectively, and arranged along a second direction, where the first direction is perpendicular to the second direction. The conductive structure and/or the buried through electrode passes through the compound semiconductor stacking layer and surrounds or lies in the active area, where the conductive structure a