Boron δ-doping in Si using atmospheric pressure CVD

Boron δ-doping was carried out by atmospheric chemical vapor deposition. The process consists of removal of native oxide, boron adsorption at 500°C, cap-layer deposition, and solid phase epitaxy at 600°C. From SIMS results with various primary ion energies, it was found that the boron profile has a peak at the interface between the substrate and the epitaxial layer and its full width at half maximum was a few nanometer. By evaluating the crystalline quality of the cap layer, it was found that the amount of adsorbed boron atoms has to be less than a few monolayer to obtain a solid phase epitaxial layer.