N2O oxidation of strained-Si/relaxed-SiGe heterostructure grown by UHVCVD

Oxidation of strained-Si/relaxed-SiGe heterostructure grown by UHVCVD metho d using a rapid thermal processing technique in N2O ambient is investigated . The electrical properties of the grown oxide have been characterized usin g a MOS structure. Hole confinement in the SiGe layer at low field is obser ved from the capacitance-voltage curve and this suggests that the strain in the initially strained Si epilayer is retained after oxidation. The experi mental results are compared with simulation results obtained from a I D Poi sson solver. D-it and Q(f)/q values are estimated to be 3 x 10(11) cm(-2) e V(-1) and -1.2 x 10(11) cm(-2), respectively. These high values of D-it and negative Q(f)/q could possibly be due to Ge out diffusion and pile up at t he SiO2/strained-Si interface. The oxide exhibits an excellent breakdown fi eld of 15 MV cm(-1). (C) 2001 Elsevier Science Ltd. All rights reserved.