ELECTRICAL CHARACTERIZATION OF DEFECTS INTRODUCED IN N-GAAS BY ALPHA-IRRADIATION AND BETA-IRRADIATION FROM RADIONUCLIDES

We investigated defect production in n-type GaAs with two different fr ee-carrier densities (4 x 10(14) and 1 X 10(16)/cm3) by using particle s liberated from radionuclides. Sr-90 and Am-24 were employed as beta and alpha sources, respectively. The results obtained for electron irr adiation showed that the same set of primary defects can be produced b y beta irradiation from the Sr source as by electrons produced in an a ccelerator. Similarly, the defects produced by alpha irradiation from the Am source closely resemble those introduced by alpha irradiation i n a Van de Graaff accelerator. It was found that the relative concentr ations of the primary defects in electron-irradiated GaAs are differen t to those in alpha-particle irradiated GaAs. Further, for the first t ime, an alpha irradiation induced defect which seems to be related to the doping concentration was observed in the 10(16)/CM3 Si doped GaAs. It is concluded that the use of radionuclides is an inexpensive and c onvenient method to introduce and to study radiation induced defects i n semiconductors.