重离子辐照调控p型透明氧化物半导体CuAlO2薄膜缺陷及其热电性能研究

p型透明氧化物半导体（TOS）CuAlO2薄膜具有优异的理论热电性能，是实现透明热电器件的重要候选材料，但实验结果与理论计算相差甚远，主要源于载流子浓度和声子散射无法被同时有效调控。重离子辐照技术可解决上述难题，通过增大缺陷浓度、降低薄膜密度，共同改进p型TOS-CuAlO2薄膜热电性能。本项目提出采用重离子辐照CuAlO2透明薄膜可控构造缺陷，显著提升CuAlO2薄膜的功率因子和热电优值ZT值。通过改变辐照参数，包括离子种类、离子能量、流强大小、辐照剂量等，深入系统研究CuAlO2薄膜缺陷浓度、薄膜密度对样品形貌、结构、透明性、导电性，特别是热电性能的调控规律。通过比较辐照前后CuAlO2薄膜热电性能变化，构建微观缺陷、薄膜密度与宏观热电性能间的物理关联性，澄清内在物理机制。为p型TOS薄膜的热电应用提供可靠的理论依据和技术支持，开展本项目研究具有非常重要的科学意义和应用价值。

P-type transparent oxide semiconductors (TOS) CuAlO2 film is a promising candidate for transparent thermoelectric devices due to its transparency and excellent thermoelectric properties in theory. However, its thermoelectric performance is far from the theoretical prediction since the charge carrier concentration and phonon scattering in CuAlO2 films could not be modulated simultaneously. Heavy ion irradiation is believed to be an effective strategy to address this issue. The thermoelectric performance of CuAlO2 films will be significantly improved by increasing defect concentration and decreasing film density. In this project, heavy ions are proposed to irradiate CuAlO2 transparent films for creating defects. We aim to enhance the power factor and ZT value of the CuAlO2 films. A series of investigations will be performed on the irradiation effects by varying experimental parameters, including ion species, ion energy, intensity and dose. The comprehensive study is accomplished on the changes of defect concentration, film density, morphology, structure, transparency and electrical conductivity, especially the thermoelectric properties of the CuAlO2 films. The irradiation effect of heavy ions on CuAlO2 films will be concluded through a comparative study on the irradiated and unirradiated samples. The connections between defect concentration, film density and thermoelectric properties will be built. The intrinsic physical mechanisms are clarified in the connections. It will provide a reliable technical and theoretical support for the thermoelectric improvement of p-type TOS films. Moreover, the proposed project will also generate a design guideline of transparent thermoelectric devices.