High-power subnanosecond silicon avalanche shaper

The ultrafast (subnanosecond) switching of a high-voltage silicon avalanche shaper (SAS) diode from a blocking to conducting state is performed by applying an overvoltage pulse with a wavefront rise-rate of $\sim$10$^{12}$ V/s in the reverse direction. The forming under this condition impact ionization front fills in the diode base layer with electron-hole plasma and switches the diode to the conducting state. Besides, it is important to prevent the possible breakdown over the diode structure surface while the overvoltage pulse is applied. The first results of the investigation of principally new SAS diode design is presented. New diode construction completely excludes edge contour degradation by the overvoltage pulse. Our experiments show the usefulness of the suggested diode construction and the importance of further investigations to determine its operation limits.