Reverse annealing, clustering, and electron mobility in arsenic doped silicon

The reverse annealing phenomena and the nature of the As clusters were studied on silicon on insulator samples uniformly doped with As at concentrations up to 7.6 x 10(20) cm(-3). Carrier concentration and electron mobility were determined by Hall and resistivity measurements after annealing at temperatures in the range 550-800 degrees C. The amplitude of transient reactivation, which can involve up to 20% of the clustered As, depends on dopant concentration and on the annealing temperatures and times. The results of a detailed study of the influence of these parameters are reported. The occurrence of reverse annealing confirms the existence of different types of As clusters, whose distribution and features depend on the experimental conditions. The effect of clustered As on the electron mobility was measured and a quantitative relationship for this phenomenon is reported. The amplitude of this effect is in agreement with the view that at room temperature As clusters are electrically neutral. (C) 2000 American Institute of Physics. [S0021-8979(00)03202-3].