Heteroepitaxial Si/Si1-xGex/Si structures produced using pulsed UV-laser processing

High quality heteroepitaxial regrowth of arsenic-implanted a-Si on Si1-xGex layers with Ge fractions between 0 and 0.2 is accomplished using pulsed laser induced epitaxy (PLIE). The structures of boron-doped Si1-xGex on Si(100) are created beforehand using a combination of (PLIE) and gas immersion laser doping. A small amount of Ge and B backdiffusion from the Si1-xGex film into the top Si layer is observed. During the laser pulse, the implanted arsenic diffuses up to the maximum melt depth so that melt depth and junction depth coincide. The a-Si is sputter deposited to a thickness of 900 A, and the As is implanted to a dose of 5x1014 cm-2 at 40 keV. A single XeCl excimer laser pulse with an energy fluence to be selected between 0.6 and 0.8 J/cm2 is sufficient to heteroepitaxially regrow the a-Si and activate the implanted arsenic