Type conversion in irradiated silicon diodes

Abstract

We have observed conversion from p- to n-type of the base layer of n+\p\p+ silicon diodes irradiated with more than roughly 5×1016 cm−2 1 MeV electrons. Annealing for 15 min at 200 °C results in a recovery of p-type conduction in diodes in which type conversion had been induced. Solar cells which employ the same diode structure are severely degraded by irradiation with more than 1016 cm−2 1 MeV electrons and show only a weak infrared response after irradiation with 1017 cm−2 1 MeV electrons, consistent with the creation of an n+\n\p structure due to type conversion.