RESUMEN
Transparent conductive oxide (TCO) thin films represent a large class of wide-bandgap semiconductors applied in all fields of micro- and optoelectronics. The most widespread material applied for the creation of TCO coatings is indium-tin oxide (ITO). At the same time, there are plurality trends to change the high-cost ITO on other materials, for example, on the ZnO doped by different elements such as Al, Mn, and Sb. These films require mobile and low-cost evaluation methods. The dynamic hot-probe measurement system is one of such techniques that can supplement and sometimes replace existing heavy systems such as the Hall effect measurements or the Haynes-Shockley experiments. The theoretical basis and the method of analysis of the recorded dynamic hot-probe characteristics measured at different temperatures were presented in this work. This method makes it possible to extract the main parameters of thin films. Commercial thin ITO films and new transparent conducting ZnO:Al layers prepared by magnetron co-sputtering were studied by the proposed method. The measured parameters of commercial ITO films are in agreement with the presented and reference data. In addition, the parameters of ZnO:Al thin films such as the majority charge carriers type, concentration, and mobility were extracted from dynamic hot-probe characteristics. This method may be applied also to other wide-bandgap semiconductors.
RESUMEN
Localized surface plasmons-polaritons represent collective behavior of free electrons confined to metal particles. This effect may be used for enhancing efficiency of solar cells and for other opto-electronic applications. Plasmon resonance strongly affects optical properties of ultra-thin, island-like, metal films. In the present work, the Finite Difference Time Domain (FDTD) method is used to model transmittance spectra of thin gold island films grown on a glass substrate. The FDTD calculations were performed for island structure, corresponding to the Volmer-Weber model of thin film growth. The proposed simulation model is based on fitting of experimental data on nanostructure of ultra-thin gold films, reported in several independent studies, to the FDTD simulation setup. The results of FDTD modeling are then compared to the experimentally measured transmittance spectra of prepared thin gold films and found to be in a good agreement with experimental data.