Application of Modified Rapid Thermal Annealing to Doped Polycrystalline Si Thin Films Towards Low Temperature Si Transistors.

Abstract

Modified thermal annealing was applied to the activation of the polycrystalline silicon films doped as p-type through implantation of <TEX>$B_2H_6$</TEX>. The statistical design of experiments was successfully employed to investigate the effect of rapid thermal annealing on activation of polycrystalline Si doped as p-type. In this design, the input variables are furnace temperature, power of halogen lamps, and alternating magnetic field. The degree of ion activation was evaluated as a function of processing variables, using Hall effect measurements and Raman spectroscopy. The main effects were estimated to be furnace temperature and RTA power in increasing conductivity, explained by recrystallization of doped ions and change of an amorphous Si into a crystalline Si lattice. The ion activation using rapid thermal annealing is proven to be a highly efficient process in low temperature polycrystalline Si technology.