High-temperature annealing of electron-irradiated high-voltage diode structures on neutron transmutation-doped Si

High-voltage diode structures were fabricated in high-resistance neutron transmutation-doped (NTD) silicon and irradiated with 6 MeV electrons. A non-equilibrium minority charge carrier (NMCC) lifetime was measured in the high-resistance region of p+-n structures and deep-level transient spectroscopy (DLTS) was used to determine the concentration and energy level positions of radiation-induced defects as a function of annealing temperature in the range 300--800 °C. The results suggest that in structures of the type investigated here, defects are formed with high thermal stability up to 800 °C and with a high formation efficiency when exposed to radiation. These defects' properties as recombination centers can be used for the fabrication of fast power diodes; their incorporation into device structures should be made at the fabrication stage preceding the formation of ohmic contacts.