Surface and Electrical Properties of Inductively-coupled\\Plasma-etched N-face n-GaN and a Method of Reducing the Ohmic\\Contact Resistance of Plasma-damaged N-face n-GaN

An investigation of the surface and the electrical properties of inductively-coupled plasma (ICP)-etched N-face n-GaN is reported. Furthermore, a method for reducing the Ohmic contact resistance on plasma-damaged N-face n-GaN is proposed. The I - V characteristics show that the Cl-2 flow rate used for the ICP etching has a strong influence on the Ohmic behavior of the etched N-face n-GaN. We also found that the surfaces of the ICP-etched N-face n-GaN were damaged by increasing the Cl-2 flow rate, resulting in deteriorating Ohmic behavior. However, the plasma damage caused by the ICP etching could be removed by using a KOH etching process, which resulted in a decreased contact resistance.