The defects at abrupt and ultra-thin thermal silicon dioxide mediated Si(100)/a-Al2O3 interfaces were studied by X-band electron paramagnetic resonance spectroscopy. Amorphous Al2O3 films of 4nm thickness were deposited by atomic layer deposition at 300C. Different deposition conditions and post-deposition annealing were investigated. In all cases the main interface defects were found to be the two Pb centers (Pb0, Pb1) known from previous Si/SiO2 interface studies. The Pb0 center was dominating in concentration with Pb0/Pb1 ratios higher than 5. The concentrations were in the 1012 to 1013/cm3 range. Forming gas annealing at 450C did reduce the Pb center concentrations only by 50%.

An Electron Paramagnetic Resonance Study of the Si(100)/Al2O3 Interface Defects. J.L.Cantin, H.J.von Bardeleben: Journal of Non-Crystalline Solids, 2002, 303[1], 175-8