Measurement of optical properties of highly doped silicon by terahertz time domain reflection spectroscopy

Optical properties of doped silicon wafers have been measured by means of terahertz time domain reflection spectroscopy. A method is proposed to obtain the relative phase by reflection accurately. By using this method, the relative phase is obtained within an error of less than 10 mrad at 1 THz. The experimentally obtained complex conductivity of relatively high-doped silicon $\text{(ρ=0.136\hspace{0.05em}Ω\hspace{0.05em}}\mathrm{cm})$ in the terahertz region agrees with the simple Drude model.