Investigation of Electrical Properties of Thermally Annealed SiGe Metal–Oxide–Semiconductor Capacitors Prepared by Liquid-Phase Deposition of Silicon Dioxide

Abstract

Room-temperature (30 C) silicon dioxide (SiO 2 ) has been grown on strained SiGe layers by liquid-phase deposition (LPD). Metal-oxidesemiconductor (MOS) capacitors have also been fabricated by annealing at various temperatures (200 -400 C) in nitrogen. A very low leakage current density of 3:25 Â 10 À8 A/cm 2 was obtained at an electric field of 10 MV/cm for as-grown LPD-SiO 2 films. After annealing, the leakage current density decreased by one order of magnitude and the fixed oxide charge density also significantly decreased to 4:7 Â 10 9 cm À2 in the capacitor annealed at 400 C. The mechanism by which this occurred is explained.