Study of Photo-Response of Cu2O and Cu2O+MoS2 Layers

• Main Authors: HONG YI, 洪毅
• Other Authors: WU,YOU-LIN
• Format: Others
• Language: zh-TW
• Published: 2017
• Online Access: http://ndltd.ncl.edu.tw/handle/7qe2bw

碩士 === 國立暨南國際大學 === 電機工程學系 === 105 === The main theme of this thesis is to comapre the photoresponse of Cu2O thin film and the film of Cu2O mixed with MoS2 powder with various mixed rates. The current-voltage (I-V) characteristics subjected to illumination were studied for the films prepared with different MoS2 doping concentrations, subjecting to various post-metalliation annealing (PMA) temperatures, and under different annealing environment. In this work, fluorinated tin oxide (FTO) glass was used as the subsrate. A metal layer was deposited on to the FTO glass as the bottom electrode, followed by spin-coating respectively the Cu2O and Cu2O+MoS2 layers with different concentrations. In order to get different thicknesses of the active layer, the number of spin coating was varied. The samples were cured at 70℃ for 5 min after each spin coating. The samples were completed by thermal evaporated an Al top gate onto the active layer. A 6500k incandescent lamp was used to illuminate our samples with a fixed distance of 30 cm from the sample surface, and the I-V characteristics were measured using the semiconductor parameter analyzer Agilent 4156B. For samples without subjecting to PMA, It is found that the more MoS2 concentration mixed in Cu2O, the more negative resistance behavior observed in the I-V curves and the more discrepancies between pre- and post-illuminated I-V characteristics. We also observed that, when performing PMA under nitrogen ambient, the samples either with lower MoS2 concentration and higher annealing temperature or higher MoS2 concentration and lower annealing temperature can exhibit larger difference between pre- and post-illuminated I-V characteristics. It is also found that the negative resistance behavior in the I-V characteristics becomes less apparent when the annealing temperature at 200℃ and 300℃. For the samples subjected to PMA under oxygen environment, the difference between pre- and post-illuminated I-V characteristics of the pure Cu2O samples is larger than that of the samples mixed with MoS2. For samples mixed with MoS2, it is observed that the higher the mixed ratio the larger the difference between pre- and post-illuminated I-V characteristics.