An electron paramagnetic resonance study of the Si(100)/Al2O3 interface defects

The defects at abrupt and ultrathin thermal silicon dioxide mediated Si(100)/a-Al2O3 interfaces have been studied by X-band electron paramagnetic resonance spectroscopy. Amorphous Al2O3 films of 40 Angstrom thickness were deposited by atomic layer deposition at 300 C. Different deposition conditions and post deposition annealing have been investigated. In all cases the main interface defects are found to be the two Pb centers (P-b0, P-bl) known from previous Si/SiO2 interface studies. The R-b0 center is dominating in concentration with P-b0/P-bl ratios higher than 5. The concentrations are in the 10(12)-10(13) cm(-1) range. Forming gas annealing at 450 degreesC did reduce the Pb center concentrations only by 50%. (C) 2002 Elsevier Science B.V. All rights reserved.