Summary: | 碩士 === 國立臺灣大學 === 光電工程學研究所 === 95 === In this research, we fabricate the current diverting structure by using ion implantation technology. With this structure, we can change the current flowing path to improve current spreading of the device and reduce current crowding effect. By reducing the light absorption and reflection by metal electrodes, we can increase the light extraction efficiency and light output power. Ion implantation technology has the property of changing the doping concentration of the material. Therefore we add a step of implantation in the conventional process steps to reduce the doping concentration of the p-type GaN where we want to fabricate the current diverting structure. By this, we have an area with lower concentration compared with the surrounding area and as a result, the higher resistance. As we know that the current tends to flow through a path with lower resistance, we can increase the current density of the area outside of the metal electrode. The experimental results show that at 20mA current injection, the maximum of output power enhancement is 30.3%.
|