Adsorbate induced electrical instabilities in large surface area-to-volume ratio materials

In high surface area-to-volume raito materials, p-type or n-type semiconductors, the atmospheric adsorbates such as O2 and H2O in ambient air lead to electrical instabilities in time. It is important that in order to make develop nano-electronic or nano-optoelectronic devices based on these materials, they must be electrically stable. In this thesis work, to overcome this problem, we have suggested that the surface of these materials should be encapsulated with proper dielectric material (for this purpose, SiO2 thin film as a dielectric material used in this work). Adsorbate induced electrical instabilites in high surface area-to-volume ratio materials have been investigated. For this purpose, the obtained results of graphene samples (CVD-graphene as a p-type, epitaxial graphene for n-type) have been compared as the same material but different type of conductivity. On the other hand, for different material but same type of conductivity, we have evaluated the results of epitaxial graphene and ZnO thin film samples. The obtained experimental results have been used to develop a model which describes the interactions between surface and atmospheric adsorbates in high surface area-to-volume ratio materials.