Undoped Silicon Layers Grown by Gas Source Molecular Beam Epitaxy Using Si2H6

Undoped Si layers were homoepitaxially grown on Si(001) substrates by gas source molecular beam epitaxy using pure disilane (Si2H6) at various substrate temperatures ranging from 533°C to 1000°C. Single-crystalline epilayers were obtained throughout the whole temperature range. Growth rates, crystallinity of the epilayers, and redistribution of impurities during crystal growth were investigated. Undoped layers grown at 700°C exhibited n-type conduction, with the carrier concentration in the 1014 cm-3 range and the electron mobility of 1500 cm2/V·s at room temperature.