A free-space method for S-parameter measurement of semiconductor materials at microwave frequencies

Four silicon dioxide samples with different oxide layer thicknesses have been prepared in the lab. These samples were measured using spot-focusing free-space measurement system employing metal-backed method where S
₁₁
is measured. The result shows that the measurement system could differentiate the epitaxial layer thicknesses of the oxides. Further analysis shows that this measurement technique is sensitive to the properties of the epitaxial layer only. Results are reported in the frequency range of 18-26 GHz.