This paper reports the design and preparation of ultra-fast photoconductive (PC) switch made from a 500 nm thick low
temperature grown GaAs (LT-GaAs) on a transparent quartz glass substrate. After the procedures of photolithography,
etching, evaporation etc., coplanar strip (CPS) transmission lines of Au/Pt with width and spacing of 10 μm and
thickness of 600 nm are evaporated on the substrate of LT-GaAs. The photoconductive switch has ideal dark resistance,
good I-V performance and photoelectric linearity under an exposure of weak light. The dark current is about 0.1 pA at a
bias voltage of 10 V. The typical risetime of the photoconductive switch is 1.3 ps measured by pump-probe technique
with a mode-locked Ti: sapphire laser with pulse width of 100 fs, wavelength of 800 nm, and frequency of 100 MHz.
Monte Carlo simulation method has been used to study the linear mode of photoconductive semiconductor switches
(PCSS). Its triggered source is a femtosecond laser pulse. The simulation results are well in agreement with experiment
data, so the model is accurate. Based on the model, some important factors which influence the response time of PCSS
have been analyzed by computer simulation. Then the sizes of these parameters that make an important contribution to
get better response time have been deduced. From this simulation analysis, it is sure that some experiment conditions can
be used more enough. In other words, the response time can be further shortened under the same experiment condition.
Moreover, the transition from linear mode to non-linear mode has been analyzed using this model.