An investigation of the effects of iron in p/sup +/n silicon diodes for simulated plasma source ion implantation studies

This work examines the effect of iron as a contaminate implant impurity on the characteristics of boron p/sup +/n silicon diodes. Plasma-based doping processes [e.g., plasma source ion implantation (PSII)] are subject to concerns about the introduction of contaminant impurities. Here, a relevant database on iron contaminant effects was acquired through a controlled study using conventional ion-beam implantation. Uncontaminated control diodes had leakage current densities of 6-9 nA-cm/sup -2/ at -5 volts and ideality factors <1.05. Iron contaminated diodes had increasing leakage current densities of 8-60 nA-cm/sup -2/ with increasing iron implant doses of 4/spl times/10/sup 7/ to 4/spl times/10/sup 14/ cm/sup -2/ and ideality factors <1.07 over six decades of current, regardless of dose.