Provided are touch screen panels with improved transmittance and methods of fabricating the same. the method may include preparing a substrate including a cell region and an interconnection region provided around the cell region, sequentially forming a first buffer layer and a second buffer layer on the substrate, the second buffer layer having a refractive index less than that of the first buffer layer, and forming a transparent electrode on the second buffer layer. The second buffer layer is formed of a SiOC material.