Bulk characterization of niobium-doped silicon diodes

Abstract

Rutherford backscattering spectrometry and elastic recoil detection analysis measurements were used to characterize silicon material in order to establish the amount and the depth profile of niobium implanted in the bulk of silicon. Current-voltage and capacitance-voltage measurements were carried out on the diodes fabricated on undoped and niobium-doped n-silicon. The amount of niobium implanted in n-silicon was found to have considerable effects on the electrical properties of the fabricated diodes. In I-V measurements the diodes changed from typical exponential to ohmic behaviour while in C-V measurements capacitance peaks and a negative capacitance at low frequencies were observed. In general the results indicated that niobium in silicon was responsible for change in electrical properties of the diodes. The diodes showed that they were been fabricated on relaxation material after doping with niobium. A change in diode behaviour showed that in silicon niobium was responsible for relaxation behaviour of the material. Relaxation material is radiation-hard since the effects of radiation on the material based devices are suppressed.