Prebaking and silicon epitaxial growth enhanced by UV radiation

UV light irradiation effects on prebaking and silicon epitaxial growth is studied. An ArF excimer laser, a KrF excimer laser, and a Hg-Xe lamp are used as light sources. The epitaxial growth is carried out using a SiH ₂Cl₂/H₂ system under reduced pressure. ArF radiation and Hg-Xe radiation are found to be effective for volatilizing native SiO₂ on silicon-substrate surfaces even at low temperatures. When a substrate surface is irradiated with these UV radiations during prebaking and epitaxial growth, epilayer surface morphology and crystalline quality are much improved. Furthermore, the epitaxial growth rate seems to be enhanced photothermally by excimer laser radiations, and photochemically by Hg-Xe radiation.