Two-Step Doping Using Excimer Laser in Boron Doping of Silicon

Abstract

A two-step doping method consisting of the deposition of dopant films and the incorporation of dopant atoms using excimer laser has been studied in boron doping of silicon. These processes are carried out in the same chamber successively. Sheet resistance can be varied widely by changing both the number and the energy density of the depositing laser pulses. In this method, dopants diffuse in the melted silicon from a fixed total dopant source with a simple Gaussian distribution when the number of melting pulses is small. The diffusion coefficient of B in liquid Si is determined experimentally.