DEGRADATION AND RECOVERY OF IN0.53GA0.47AS PHOTODIODES BY 1-MEV FAST-NEUTRONS

Irradiation damage in In0.53Ga0.47As p-i-n photodiodes by 1-MeV fast n eutrons is studied as a function of fluence for the first time. The de gradation of the electrical and optical performance of diodes increase s with increasing fluence. The induced lattice defects in the In0.53Ga 0.47As epitaxial layers and the InP substrate are studied by DLTS meth ods. In the In0.53Ga0.47As epitaxial layers, hole and electron capture levels are induced by irradiation. The influence of radiation source on device degradation is then discussed by comparison to 1-MeV electro ns with respect to the numbers of knock-on atoms and the nonionizing e nergy loss (NIEL). In order to examine the recovery behavior, isochron al thermal annealing is carried out for temperatures ranging from 75 t o 300 degrees C. After 300 degrees C thermal annealing, the light curr ent only recovers to 20% of preirradiation for a fluence of 1 x 10(13) n/cm(2), while it recovers to 53% for a fluence of 1 x 10(15) e/cm(2) . The different of recovery behavior is thought to be due a different type of radiation damage.