ANALYSIS THE EFFECT OF ANNEALING ON OPTICAL PROPERTIES OF Ti:ZnO USING SPECTROSCOPY ELLIPSOMETRY

• Main Author: EVA YOHANA (NIM : 10213044), M.
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/28875
• Institution: Institut Teknologi Bandung

<p align="justify">ZnO with three different consentration of Ti doping was deposited above quartz substrate using sputtering. Furthermore, post thermal annealing in atmosphere pressure was given in order to get the optimum optical and structural property of Ti:ZnO. To study the effect of annealing, sample was characterized using x-ray diffraction (XRD), fourrier transform infrared (FTIR), spectroscopic ellipsometry (SE) and UV-Vis. The result of XRD and FTIR shows an enhance crystalinity of Ti:ZnO followed by strain lattice effect caused from the difference of themal expansion coefficient between substrate and thin film. From SE characterization, we found that thickness increase as the effect of oxygen binding from the unvacuum evironment during cooling down process of annealing. This oxygen binding will reduce defect by filling the oxygen vacancy that play important role for the contribution of free carrier electron. Reduction of oxygen vacancy will decrease carrier concentration and cause the increasing of exciton binding energy. Furthermore, oxygen binding also cause the increase of trasmittance by reducing the center of photon scattering. However, in another sample, the decrease of carrier concentration also caused and dominated by thickness reduction from etching effect of annealing. In this case, the shift of bandgap is not followed by the increase of transmittance, but rather by the decrease of transmittance caused by the rough surface from the act of etching.<p align="justify">