Terahertz detector based on GaN MIS-HEMT structure and preparation method thereof

The invention discloses a terahertz detector based on a GaN MIS-HEMT structure and a preparation method of the terahertz detector. The terahertz detector comprises a substrate layer; the composite buffer layer is arranged on the substrate layer; the channel layer is arranged on the composite buffer layer; the barrier layer is arranged on the channel layer; a source electrode, a drain electrode and a gate electrode, the source electrode, the drain electrode and the gate electrode are all arranged on the barrier layer, and the gate electrode is located between the source electrode and the drain electrode; and the insulating medium layer is arranged between the barrier layer and the gate electrode. The GaN MIS-HEMT structure based on the semiconductor field is introduced into the terahertz detector, the insulating medium layer is introduced below the gate electrode of the GaN HEMT terahertz detector, and the GaN MIS-HEMT structure is utilized to reduce the gate current and the gate flicker noise, so that the per