| Summary: | 碩士 === 國立中山大學 === 物理學系 === 87 === High temperature superconductor have been discovered. In order to make the application of superconductor to be more widespread, we combine the technique of semi-conductor. We deposited superconductor thin films on silicon surface and expected it has good application. Because the lattice matches the(001) orientation of YBa2Cu3O7~5 and silicon, it is possible to choose silicon as substrate. But Ba and Si attend to interact as chemical compound, Ba-Si-O. So it can't becomed normal superconductor structure. This disadvantage will be overcome by growing a buffer-layer between silicon substrate and YBCO crystal. We use the RF-sputter to deposit the buffer layer.
When we grow YSZ by use of RF-sputter, O2 moves to silicon wafer in the electric field , and silicon interacts with O2 to form the chemical compound, SiO2. YSZ it's difficult to epi-deposit.
We try to deposit the YSZ at 700℃, because YSZ will not deliver O2 to silicon at low temperate. We change the distance between the e-gun and heater、oxygen pressure、the ratio of O2 pressure to Ar pressure、and deposition temperature.
From now on, we have deposited the more pure film of YSZ, however we still could not control the orientation of deposition very well, because there are more complex variables in it, which keeps us on researching in this field.
|
|---|
