Investigations on the Cosputtered Transparent Electrode Ohmic Contacts to N-GaN and Its Applications to P-ZnO/N-GaN Heterojunction Diode

• Main Authors: Nan-Jay Wu, 吳南傑
• Other Authors: 劉代山
• Format: Others
• Language: zh-TW
• Published: 2012
• Online Access: http://ndltd.ncl.edu.tw/handle/8v57t9

碩士 === 國立虎尾科技大學 === 光電與材料科技研究所 === 100 === In this study, the transmission line model produced in the GaN epitaxial layer at room temperature was usingt the RF magnetron sputtering system, the zinc oxide and the indium tin oxide were slected for the sputtering targets to deposite the indium tin oxide-zinc oxide conductive film a theoretical value of the zinc atoms doping concentration for 33% as the ohmic contact electrodes., Auger electron spectroscopy of the depth distribution of visible light - ultraviolet spectrometer measured ohmic contact characteristics change mechanism. The results show that indium tin oxide - zinc oxide and n-type GaN can not be the ohmic contact, while the titanium / aluminum titanium / indium-tin oxide - zinc oxide and n-type GaN before the rapid thermal annealing excellent ohmic contact, characterized by resistance values were 5.09 × 10-4 Ωcm2 4.82 × 10-5 Ωcm2; penetration aspects of the indium tin oxide - zinc oxide between the n-type GaN thin titanium metal, although the average the transmittance of visible light on a downward trend, but the material parameter φ is significantly improved. Finally, the production p-ZnO/n-GaN with the heterostructures p-ZnO/i-ZnO/n-GaN the diode, Ti / Al and Ti / indium-tin oxide - zinc oxide transparent electrode as n type GaN ohmic contact electrode, a nickel / indium-tin oxide transparent electrode as the electrode contact with the p-type ZnO ohm, the measured light-emitting diode semiconductor parameter analyzer and fluorescence, the amount of current - voltage characteristics and electrical excitation radiation spectrum, the results show that the heterojunction diode (p-ZnO / n-of GaN p-ZnO/i-ZnO/n-GaN) structure has a pn-contact rectifier diode characteristics, but from electrical excitation emission spectrum informed that no significant electrical excitation light emission peak infer possible causes of the p-ZnO / n-GaN and p-ZnO/i-ZnO/n-GaN heterojunction diodes after thermal annealing process, due to interface diffusion mechanism, and thus deterioration of the aluminum nitride - zinc oxide sputtered thin films of conductive patterns affect the interface contacts and features, and thus there is no obvious electrical excitation light-emitting radiation.