Effect of swift heavy ion irradiation on the electrical characteristics ofAg/n-Si Schottky diode

The modifications in capacitance-voltage (C-V) and current-voltage (I-V) ch aracteristics of Ag/n-Si Schottky diode induced by 180 MeV Ag-107(14+) ion irradiation at low temperature (80 K) have been studied. The C-V and I-V ch aracteristics were recorded in situ at various irradiation fluences (from 5 x10(10) to 1x10(13) ions cm(-2)). The capacitance of the unirradiated diode at zero bias was 778 pF and after irradiation with a fluence of 5x10(10) i ons cm(-2), its value sharply decreased to 286 pF. After this fluence, ther e was a relatively slow decrease in capacitance. Similarly, the modificatio ns in I-V characteristics induced by swift heavy ion irradiation have also been studied. Thermionic field emission theory of current transport has bee n applied to explain the observed modifications in I-V characteristics. The variations in characteristic energy parameter Eo, reverse saturation curre nt I-S and ideality factor n with fluence have been investigated. The nucle ar energy deposition near the metal-semiconductor (MS) interface causes the production of defects which alter the C-V and I-V behaviour of the diode. On the other hand, the electronic energy loss, which is very large in compa rison to the nuclear energy loss at the MS interface, may induce partial an nealing of the defects.