Terahertz integrated device using a transferred thin-film GaAs layer on silicon substrates

We developed thin-film GaAs transfer technique for integrated terahertz (THz) generating and detecting devices. Photoconductive switch elements on Si substrate are important for avoiding GaAs absorption to measure in wide frequency range. THz emission amplitude and Fourier transform spectrum band range become larger by replacing GaAs substrate with Si substrate. Transmission line device with the transferred GaAs layer on Si substrate is also fabricated for high sensitive sensors. It was found that peak shift of THz pulse was proportional to apply volume of samples and the sensitivity strongly depended upon the width of the transmission line.