Preparation of CuCrO2 thin films using atmospheric pressure plasma annealing

• Main Authors: Chi-Huang, 黃麒
• Other Authors: Hong-Ying Chen
• Format: Others
• Language: zh-TW
• Published: 2015
• Online Access: http://ndltd.ncl.edu.tw/handle/qhb34h

碩士 === 國立高雄應用科技大學 === 化學工程與材料工程系博碩士班 === 103 === This study used the atmospheric pressure plasma annealing to prepare the CuCrO2 thin films with and without Mg-dopants. The thin films were coated on quartz substrates using the sol-gel process followed the atmospheric pressure plasma annealing with N2-(0-20%)O2 for 20 min for Mg-doped CuCrO2 thin films. The CuO and Cr2O3 phase appeared in N2-0%O2 ; however, a pure delafossite-CuCrO2 phase was detected at the N2-(3%-10%)O2.CuCrO2 and CuO phase appeared at N2-20%O2. The dense CuCrO2:Mg thin films was observed at the formation of the CuCrO2 phase. The CuCrO2:Mg thin films had a optical bandgap of 3.05 eV at N2-5%O2 and N2-10%O2. The electrical conductivity of the thin films was 6.00×10-2 S/cm with the carrier concentration of (9.7±3)×1014 cm-3 at N2-5%O2 and 4.72×10-1 S/cm with the carrier concentration of (4.8±2)×1016 cm-3 at N2-10%O2. For the CuCrO2 thin films prepared in this study, CuO and CuCr2O4 phase first appeared in N2-21%O2 and then transformed into a pure delafossite-CuCrO2 phase in N2-(5 and 10%) O2. The XPS indicated that the binding energies of Cu-2p1/2, Cu-2p3/2, Cr-2p1/2, Cr-2p3/2, and O-1s were 951.8 eV, 932.0 eV, 585.6 eV, 576.0 eV, and 530.0 eV, respectively, as the formation of CuCrO2 phase. According to the XPS results, Cu and Cr in CuCrO2 thin films were Cu+1 and Cr+3. The CuCrO2 thin film annealed in N2-10%O2 contained more pores than that annealed in N2-5%O2. The average transmittance and the optical bandgap of the CuCrO2 thin films was 52~45% in visible region and 2.93~2.91 eV, respectively. The electrical conductivities of the CuCrO2 thin films were (2.03±0.09)×10-3 S/cm and (2.40±0.154)×10-3 S/cm when annealed at N2-5%O2 and N2-10%O2, respectively. The corresponding carrier concentrations of the CuCrO2 thin films were (1.82±0.69) ×1015 cm-3 and (6.53±6)×1014 cm-3 at N2-5%O2 and N2-10%O2, respectively. The CuCrO2 thin film was P-type confirmed by Seebeck coefficients. This study develops a quick method to prepare CuCrO2 films and can be applied to preparation of other thin-films.