Preparation And Properties Of CuAlO₂Target And Thin Film

CuAlO2is a ternary compound semiconductor with high transmittance in visible light range, direct optical band gap is3.45eV, and indirect band gap is1.8eV, CuAlO2is the first delafossite strcuture compound which shows un-doped p-type semiconductor properties. Now, p-type transparent conductive oxides can not compared with the widely used n-type semiconductor oxides in practical application, and CuAlO2is a p-type promissing material which shows a very broad prospect in photoelectric field, and can be applied to ozone sensor, thin film solar cell, etc. If CuAlO2see dramatic breakthroughs, then transparent oxide p-n junction optoelectronic devices can be fabricated, and also can promote the development of oxide semiconductors.This thesis used analytical pure Al2O3and Cu2O as the raw materials, and prepared the CuAlO2ceramic targets by high temperature solid state method, though the XRD, density and electrical properties analysis, we found the optimum sintering temperature for CuAlO2is1200℃, and the density and resistivity of target are92%and103Ω·cm, then we also prepared3%Zn-doped CuAlO2ceramic target by this method.Based on the targets that we preapred before, we deposited Cu-Al-O thin film by pulsed laser deposition technology, through the annealing treatment we get the CuAlO2thin film successfully. And using XRD, SEM, UV, and other methods to analysis the influence of substrate, temperature, growth pressure, deposition time factors on the structure and properties to CuAlO2thin film, and got the best processing parameters to deposite CuAlO2thin film by PLD method:c-surface sapphire substrate,500℃,1.0Pa and60min or30min.Then we analysed the photo luminescence properties of CuAlO2thin film which deposited on optimum parameters. We found the band edge emission peak is around360nm which corresponding to the3.44eV bang gap, and also we found a defect peak near465nm which caused by Cu vacancy. Compared with our previous research we consider that the origin of CuAlO2p-type property is Cu vacancy. Then we analysed the influence of Zn doped for CuAlO2thin film, found that it has little effect to the Raman vibration of Cu-O, and the conductivity has a little increased, but it can also increased the surface roughness for CuAlO2thin film.Finally, we used sol-gel method to prepare the CuAlO2and Zn doped CuAlO2 powders, by the photocatalysis test, we found CuAlO2have a19%catalytic efficiency to0.01mmol/L of Rhodamine B, and Zn doping can increase the catalytic efficiency.