Pulse Power Generation in Nano- and Subnanosecond Range by Means of Ionizing Fronts in Semiconductors: The State of the Art and Future Prospects

Ionization front propagation in a high-voltage reversely biased silicon p-n diode is the fastest nonoptical process of electron-hole plasma generation in semiconductors. It is capable of switching a high-voltage semiconductor structure from the blocking to the conducting state within several hundreds of picoseconds. Double-donor electron traps with ionization energies of 0.28 and 0.54 eV are the main source of carriers which initiate formation and propagation of these fronts. Dinistor n(+)-p-n-p(+) structures with such a switching mechanism are capable of generating electric pulses with several kiloamperes of amplitude and nanosecond and even subnanosecond pulse rise time. High-power pulse generators based on these devices have been developed and found applications in many modern technologies. Our numerical simulations indicate a possibility to excite new types of impact ionization fronts which are capable of switching high-voltage devices within dozens of picoseconds.