Schottky barrier photodetector on n-type freestanding GaN substrates.

• Main Authors: Kao, Yu-ting, 高郁婷
• Other Authors: 李威儀
• Format: Others
• Language: zh-TW
• Published: 2011
• Online Access: http://ndltd.ncl.edu.tw/handle/45785282586673986553

碩士 === 國立交通大學 === 電子物理系所 === 99 === In this thesis, the high quality thick GaN substrates had been grown and characterized by Hydride Vapor Phase Epitaxy (HVPE). Then, the Schottky barrier photodetectors with freestanding GaN substrates were fabricated. This thesis is made up of two parts. In the first part, we focused on the difference between the schottky diodes prepared on the 2μm-thick GaN substrates by MOCVD and 300μm-thick GaN substrates by HVPE. It was found that leakage current of the PDs prepared on freestanding GaN substrate was significantly smaller due to the improved crystal quality. In the second part, we reported the fabrication of verticle photodetectors (PDs) on freestanding GaN substrate. Compared with the lateral PD prepared on the same substrate, We found the vertical PDs had smaller leakage current. It was also found that we can reduce the photoconductive gain and enhance ultraviolet-to-visible rejection ratio by using the vertical PDs with freestanding GaN substrates.