Study on opto-electronic properties of nano-scale carbon material and metal-doped zinc-oxide composite thin films

• Main Authors: Jing-Tien Jou, 周敬添
• Other Authors: Fang-Hsing Wang
• Format: Others
• Language: zh-TW
• Published: 2018
• Online Access: http://ndltd.ncl.edu.tw/handle/4c58c3

博士 === 國立中興大學 === 電機工程學系所 === 106 === In this study, first of all, we made a composite thin film with multi wall carbon nanotubes and AZO. The ratio of the MWCNT in sol–gel solution ranges from 0.01 to 1.0 wt.%. This study investigates the effects of MWCNT ratio on structural, electrical, and optical properties of AZO:MWCNT thin films. The XRD analysis showed a strong (0 0 2) peak along the c axis at 2θ ~ 34.4o indicating a hexagonal wurtzite structure for the AZO:MWCNT thin films. The intensity of (0 0 2) peak decreased with the increasing MWCNT ratio, revealing that AZO were bounding with the MWCNTs. The sheet resistance of AZO:MWCNT thin films significantly decreased from 1.38 × 104 to 10.5 Ω/□ with increasing the MWCNT ratio from 0.01 to 1.0 wt.%; meanwhile, the optical transmittance in the visible wavelength region decreased from 87.9% to 12.1%, respectively.Second, a reduced graphene oxide and AZO thin film had been made. The sheet resistance of the films was reduced when the rGO ratio increased from 0 to 3.0 wt%. The optical transmittance of the composite film decreasedwith increasing the rGO ratio from 0 to 3.0 wt%. The average optical transmittance (400–700 nm) of the AZO/rGO composite thin film within 1.0 wt% rGO was above 81% and the sheet resistance was 430Ω/□. Finally, .a highly stable, transparent, and flexible composite electrode was developed using reduced graphene oxide (rGO)/AgNWs/Ga–doped zinc oxide (GZO) composite thin films. TherGOfilm was first spin　coated on flexible substrates and used as an adhesion enhancement layer.　The AgNWs, which were used as a primary conductor, formed a random percolating network embedded between the rGO and GZO films. TheGZO film was sputtered on the surface of the AgNWsand was used as a protective layer to prevent the oxidation of　the AgNWs. The rGO/AgNWs/GZO composite thin film exhibited excellentelectrical conductivity and superior stability to a monolayer or a bilayer TCF. The sheet resistance of the composite film was 5.5±0.5 Ω/□ when exposed to the atmosphere for 60 days. The rGO/AgNWs/GZO composite film exhibited an optical transmittance of approximately 84% at a wavelength of 550 nm. A bending test was conducted for 600 cycles with a curvature radius of 1 cm, and the test results revealed that sheet resistance of the composite film varied by less than 10%. The developed rGO/AgNW/GZO transparent conducting thin films have potential for use in future flexible optoelectronic devices.