Embodiments of the present disclosure describe apparatuses, methods, and systems of an integrated circuit (IC) device. The IC device may include a buffer layer disposed on a substrate, the buffer layer including gallium (Ga) and nitrogen (N), a barrier layer disposed on the buffer layer, the barrier layer including aluminum (Al) and nitrogen (N), a regrown structure disposed in and epitaxially coupled with the barrier layer, the regrown structure including nitrogen (N) and at least one of aluminum (Al) or gallium (Ga) and being epitaxially deposited at a temperature less than or equal to 600° C., and a gate terminal disposed in the barrier layer, wherein the regrown structure is disposed between the gate terminal and the buffer layer. Other embodiments may be described and/or claimed.