ArF excimer laser doping of boron into silicon

Abstract

Boron doping into silicon has been investigated using an ArF excimer laser. Dopant atoms are obtained by pyrolysis of BF3. Two kinds of doping, the doping in BF3 ambients and the doping using adsorbed layers, have been performed. In both cases, the sheet resistance decreases with increasing the number of pulses. The surface concentration and the junction depth increase with the number of pulses. From these results, it is found that dopant atoms are supplied from only adsorbed layers of BF3 formed on the silicon surface. Moreover, the supply of dopant atoms from adsorbed layers limits the doping process.