Using microelectromechanical system (MEMS) technologies including magnetron sputtering, ultraviolet lithography and chemical vapor deposition, two kinds of high-voltage switches based on Schottky diode and p-n diode were designed and fabricated. Electrical characterizations were performed to investigate their performances under no-load condition, which showed that the current peaks of the two switches reached up to about 2000 A at 0.22 μF/1500 V and 0.22 μF/1200 V, respectively. The influence of trigger capacitor, trigger voltage, main voltage, dielectric film thickness and bi-diode structure on the conduction performance of single shot switch was studied. It is revealed that the minimum trigger voltage decreased gradually with the increase of capacitance. Reducing the thickness of dielectric film, increasing the trigger voltage and main voltage are all beneficial to improve the current peak. Besides, bi-diode structure can also improve the current peak. Finally, according to the electrical curves of single shot switch, its action process can be divided into three stages, namely the electro-explosion of diode, the breakdown of dielectric film and the rise of pulse current. The conduction mechanism and resistance model of single shot switch were also established. The results indicate that the resistance of single shot switch is very low, almost negligible.