A novel method to suppress transient enhanced diffusion of low energy implanted boron based on reactive plasma etching

The effect of plasma processing on the transient enhanced diffusion of implanted boron in silicon is presented. Thermally oxidised silicon wafers were first etched by plasma and subsequently implanted with boron, with energies ranging from 3 to 20 keV and a dose of 1/spl times/10/sup 13//cm/sup 2/. Secondary ion mass spectrometry measurements of the boron profiles in plasma processed samples reveal a strong reduction of the transient diffusion after rapid thermal annealing, with respect to the corresponding not etched samples. The suppression of the transient enhanced diffusion is explained in terms of trapping effects, occurring between the dislocations induced by plasma bombardment and the point defects generated during the implant.