Scattering parameters of semiconductor microstrip line under laser spot illumination

Scattering parameters of an optically controlled microstrip gap fabricated on the semiconductor substrate have been analyzed theoretically using the frequency-dependent finite-difference time-domain method. The transmission characteristics of interest have been shown as a function of arbitrary position of laser spot around an air gap. The results have been demonstrated experimentally using microstrip line with silicon substrate and semiconductor laser. And, it is also reported that the high-powered illumination of laser spot develops non-dispersive characteristics of S/sub 21/ for the wide frequency range.