VASE: Instrument to Study Biaxial Organic Molecular thin Films

Abstract

Spectroscopic ellipsometry was employed to determine the complex refractive index and dielectric function of a N,N'-dimethylperylene- 3,4,9,10-dicarboximide (DiMe-PTCDI) film grown on S-GaAs(100). The optically biaxial film shows strong anisotropy. From the investigations, we can conclude that the DiMe-PTCDI molecules in the organic layer are predominantly oriented with their long axis parallel to the [011] direction of the GaAs substrate and tilted with their molecular plane with respect to the substrate plane.