Studies On The Preparation And Related Properties Of High Temperature Superconductor Films

This study mainly divided into two parts: the first part is the growing conditions and the characters of the YBCO thin film, the preparation and characters of Tl2212 thin film is on the second part.The first part, the substrate lattice of LaAlO3 and YBCO match well and it is relatively easy to grow YBCO thin film on LaAlO3 substrate, so this article study the directly growth of YBCO thin film on LaAlO3 substrate by the method of pulsed laser deposition (PLD). It is systems explored that the impact on YBCO thin film of different technical parameters, such as the substrate temperature, the distance between the target and the substrate, laser pulse frequency, laser energy, deposition pressure, and the film thickness, etc. and the best film of the deposition process is found.However, the thin film made by the method of PLD will inevitably cause some problem, for example the surface of small particles and sediment thickness of the film are also uneven. These shortcomings will seriously affect the characters of film, such as Jc, Rs, and so on. In order to improve the process of stability and yield and further lay the foundation for the application of superconductor, this paper explore the improvement of the uniformity of the film and the consistency of the double thin film. The second part introduced Tl2212 thin film by two-step Preparation. First of all, we study the growth conditions of Tl source and find the best experimental temperature. Then Films is prepared in the atmospheric pressure at the different temperature to explore the best experimental conditions.It is analysed that the success of the film samples by XRD, SEM, etc. The result shows that the film has good C-axis oriented, good surface characteristics, the specific characters of indicators such as: Rs less than 0.5 m ?, the uniformity of the critical current density, the number of all the 106 level and above, the highest superconductor transition temperature of 108.1 k. The specific experimental results show that we can prepared the uniform double film for the measurement of microwave by the method of single temperature.As the market potential of the microelectronics devices gradually increase, so the application of superconductor are also made new demands. In order to make Josephson junction using the method of ion implantation, and further prepared SQUID devices by the corresponding method, first we implant the film by H2+ in order to find the most appropriate dose to make a basis for the behind work.