The Effects of Electron Irradiation on the Current-Voltage and Capacitance-Voltage Measurements of Sn/P-GaAs Diodes

Abstract

In this study 11 (eleven) Sn/p-GaAs/Au diodes were identically fabricated. Au and Sn metals were used in order to fabricate the ohmic and rectifier contacts, respectively. The effect of electron irradiation of high electron energy of 6, 12, 15 and 18 MeV and low electron fluence of 1 x 10(12) electrons/cm(2) on the various parameters such as barrier height (BH), ideality factor (IF), series resistance (R-s), and rectification ratio (RR), acceptor concentration (N-a), diffusion potential (V-d) obtained from current-voltage (I-V) and capacitance-voltage (C-V) characteristics of Sn/p-GaAs/Au diodes was evaluated. The BH value of one (D2) of the unirradiated 11 Sn/p-GaAs/Au diodes was calculated as 0.82 eV, 0.86 eV and 0.94 eV from ln(I)-V characteristics according to the thermionic emission (TE) theory, modified Norde's functions, and C-V characteristics, respectively. The BH values calculated ln(I)-V and Norde's functions were found to be very close to each other. The values of RR, IF, and BH of D2 diode calculated from ln(I)-V according to TE theory were calculated as 1 x 10(6), 1.09 and 0.82 eV, 1 x 10(6), 1.06 and 0.81 eV, 1 x 10(6), 1.09 and 0.82 eV, 1 x 10(6), 1.12 and 0.83 eV, 1 x 10(6), 1.13 and 0.82 eV for before and after 6, 12, 15 and 18 MeV electron irradiation, respectively. The R-s value of unirradiated and 6, 12, 15 and 18 MeV electron irradiated D2 diode was calculated from Norde's function was calculated 29, 30, 30, 27, and 26 omega, respectively. Since these parameters remain nearly unchanged after electron irradiation, it can be said that electron radiation has no significiant effect on ln (I)-V characteristics and the Sn/p-GaAs/Au diodes are insensitive to high-energy electron-irradiation.