Characterization of nanoporous alumina using terahertz reflectometry and scattering imaging

The structure and morphology of nanoporous alumina (NP Al
2
O
3
) films on Al substrates are investigated by terahertz (THz) reflectometry and scattering imaging. One inhomogeneous area is identified in THz C-scan results off specular conditions at various angles. The thickness of NP Al
2
O
3
films calculated based on THz results is in excellent agreement with destructive cross-sectional field emission scanning electron microscopy (FE-SEM) measurements.