Abstract
The thesis is divided into two parts. First, we investigate the fabrication and characterization of different mesa structure and observe the trend of leakage whether it is dominated by the perimeter or not for LEDs. Moreover, we change the finger number of interdigitated LEDs to proof that the leakage increases exponentially again. On the other hand, we would like to observe if ICP do different damages to different finger spacing of interdigitated LEDs and leads to different trend of leakage. In the end, we use different passivation such as Al2O3 by ALD, SiO2 and SiN by PECVD to improve the leakage. Second, we attempt to apply the above research results on the metal- semiconductor-metal (MSM) photodetector by asymmetric electrode structures. As far as known, the surface leakage is the dominant mechanism for dark current for MSM PDs. With the higher density of trap states on the surface, the higher leakage current is obtained. Therefore, we would like to reduce the leakage current by depositing passivation layer, which is based on the previous research. Moreover, we also induce the theorem of Anti-reflection (AR) coating. We hope that the passivation can reduce the leakage current without blocking the light. On the other hand, we also change the finger spacing of MSM PDs to see what their difference in characteristics is.