Strain dependence of electronic transport in semiconducting oxide thin films

该项目旨在揭示透明导电氧化物多晶薄膜中电子输运的应变依赖性。这将研究使用薄ZnO和SnO 2薄膜制备的磁控溅射在柔性硅和玻璃基板上。将通过电导率和霍尔效应测量，根据应变进行电气表征。将特别注意晶界的影响。如何修改应变的晶界势垒的电子结构，限制电子传输，将阐明使用温度依赖性霍尔效应测量的样品与可变载流子浓度。压电贡献的晶界势垒将通过比较不同纹理的ZnO薄膜，并通过比较ZnO和SnO 2薄膜。ZnO肖特基势垒的压电改性也将使用电气技术和光电子能谱研究。该项目与K. Albe，其中ZnO晶界的电子结构将被计算，这是J. Rödel和H. J. Kleebe的论文中，研究了ZnO双晶和多晶中晶界的机械调制。乔纳吉和B。- X. Xu的项目中研究了机械场和电场的耦合及其对多晶ZnO中电荷输运的影响，以及J. J. Schneider的项目中研究了极化织构ZnO陶瓷的合成和性能。

The project aims at unravelling the strain dependence of electron transport in polycrystalline thin films of transparent conductive oxides. This will be studied using thin ZnO and SnO2 films prepared by magnetron sputtering on flexible silicon and glass substrates. The electrical characterisation will be performed as a function of strain by conductivity and Hall effect measurements. Particular attention will be paid to the influence of grain boundaries. How the electronic structure of the grain boundary barrier, which limits electron transport, is modified by strain will be elucidated using temperature dependent Hall effect measurements of samples with variable carrier concentration. The piezoelectric contributions to the grain boundary barriers will be identified by comparing differently textured ZnO films and by comparing ZnO and SnO2 films. Piezoelectric modifications of ZnO Schottky barriers will also be studied using electrical techniques and photoelectron spectroscopy. The project is closely linked to a project of K. Albe in which the electronic structure of ZnO grain boundaries will be calculated, a project of J. Rödel and H.-J. Kleebe in which the mechanical modulation of grain boundaries in ZnO bi- and polycrystals is studied, a project of E. Gjonaj and B.-X. Xu in which the coupling of mechanical and electric fields and their influence on charge transport in polycrystalline ZnO is investigated and a project of J.J. Schneider in which the synthesis and the properties of polarization textured ZnO ceramics are studied.