The use of the reverse current, of an implantation-damaged diode, for the monitoring of low-dose ion implantation was presented. A linear dose-dependence of the reverse current was found after implanting 200keV 1H+, 200keV 4He+, 40keV 11B+ and 28Si+ ions to doses ranging from 5 x 109 to 1012/cm2. The temperature and temporal stability of the current, and the effect of the implantation conditions upon its magnitude, were studied experimentally and were analyzed by means of numerical simulations. The results showed that the reverse current could change considerably with time and temperature; due mainly to the dissociation of unstable VP pairs. It was shown that the method might be useful for the very low-dose uniformity mapping of ultra-deep implantation.

P.Hazdra, V.Haslar, J.Vobecky: Nuclear Instruments and Methods in Physics Research B, 1995, 96[1-2], 104-8