Investigation of the Influence of Surface Roughness on Reflective THz Measurements

When using terahertz time-domain spectroscopy in reflective configuration, the effect of surface roughness on the reflected signal should be considered to ensure reliable material classification. We investigate the effect of surface roughness by fabricating samples from different materials with defined roughness parameters. These samples are measured in a reflective goniometer setup under varying angles of incidence and reflection. The effect of surface parameters on the THz transient is investigated for a range of materials.