Tesis
Electrical Characterization of Al Doped ZnO Sol-gel Films
Autor
Pérez, Carlos R.
Fonseca, Luis F. (Consejero)
Institución
Resumen
Thin films of transparent conductive oxides (TCO) are of interest as components in different applications such as transparent electrodes, solar panels as well as gas sensors. Interest in Aluminum doped zinc oxide thin films has dramatically increased due to the availability and relative low cost of the components, when compared to other promising TCO materials such as indium tin oxide (ITO). Previous research on Al doped ZnO sol-gel thin films deposited by spin coating has shown excellent hexagonal wurtzite c-axis orientation suggesting the possibility of easy control of the chemical components and low cost of the process.
In this work an electrical characterization platform has been developed and implemented on Al doped ZnO sol-gel thin films deposited by spin coating on glass substrates. For the development of the platform a sample holder was designed and built. In addition, multiple LabVIEW™ routines that enable the automation of the electrical characterization process were created. The platform developed enables electrical characterization in terms of resistivity and Hall Effect measurements employing the van der Pauw technique. Ultimately, due to the degradation of an already existing set of films with which the platform was tested, a new set of thin films was prepared following the same procedure used for the already existing set. The resistivity of the first and new set of samples was measured as a function of temperature, and for the new set it was modeled following several conduction mechanisms used by other research teams for ZnO thin films. To complement the electrical characterization of the new set of films, EDS, AFM, XRD, and UV-VIS measurements were also performed.