AlGaN/GaN enhanced MOSFET device of trench gate structure and preparation method for AlGaN/GaN enhanced MOSFET device

The invention discloses a preparation method for an AlGaN/GaN enhanced MOSFET device of a trench gate structure based on an I-V trench depth and trench surface damage. The I-V characteristics betweena source electrode and a drain electrode are measured during the etching of the gate trench; when the I-V characteristics show that a high resistance state exists between the source electrode and thedrain electrode, the etching is stopped. The invention further discloses a manufactured device and the application of the I-V test between the source electrode and the drain electrode in representingthe gate trench depth and the surface damage of the AlGaN/GaN enhanced MOSFET device of the trench gate structure. The I-V test between the source electrode and the drain electrode is applied to determine the gate trench depth and reduce the surface damage through combining a low-power cyclic etching method. Meanwhile, the I-V test can represent whether the surface treatment process can reduce thesurface damage of the gate