[16a-P4-1~29] 13.8 Compound and power electron devices and process technology

[16a-P4-20] Electrical properties of GaN vertical pn-diode structure with Mg ion implantation

〇Shinya Takashima¹, Katsunori Ueno¹, Takuro Inamoto¹, Masaharu Edo¹, Tokio Takahashi², Mitsuaki Shimizu² (1.Fuji Electric, 2.AIST)

Keywords:GaN, ion implantation, pn junction

We have investigated the electrical properties of GaN p+/p/n structures with Mg ion implantation. A rectifying property has been observed, but the threshold voltage of forward current increase was high, thus it was different from a normal pn-junction behavior. In the EL spectrum, strong luminescence from deep trap levels was seen, suggesting the existence of many defects inside of the implanted region.
In the high voltage pn-diode structure, the reverse blocking voltages could be changed by the thickness of the n-type epi layers, but lower than the expected values from the structure and doping concentrations. The capacitance measurements give anomalous behavior. The Mg ion implanted layer may be depleted. It is necessary to improve the implanted layer, especially from viewpoints of defects.