No abstract

No abstract

Access to the full text of the published version may require a subscription. An experimental examination of the properties of the Si͑100͒-SiO 2 interface measured following rapid thermal processing ͑RTP͒ is presented. The interface properties have been examined using high frequency and quasi-static capacitance-voltage ͑CV͒ analysis of metal-oxide-silicon ͑MOS͒ capacitor structures immediately following either rapid thermal oxidation ͑RTO͒ or rapid thermal annealing ͑RTA͒. The experimental results reveal a characteristic peak in the CV response measured following dry RTO and RTA (TϾ800°C), as the Fermi level at the Si͑100͒-SiO 2 interface approaches the conduction band edge. Analysis of the QSCV responses reveals a high interface state density across the energy gap following dry RTO and RTA processing, with a characteristic peak density in the range 5.5ϫ10 12 to 1.7ϫ10 13 cm Ϫ2 eV Ϫ1 located at approximately 0.85-0.88 eV above the valence band edge. When the background density of states for a hydrogen-passivated interface is subtracted, another peak of lower density (3ϫ10 12 to 7ϫ10 12 cm Ϫ2 eV Ϫ1 ͒ is observed at approximately 0.25-0.33 eV above the valence band edge. The experimental results point to a common interface state defect present after processes involving rapid cooling (10 1 -10 2°C /s) from a temperature of 800°C or above, in a hydrogen free ambient. This work demonstrates that the interface states measured following RTP (TϾ800°C) are the net contribution of the P b0 / P b1 silicon dangling bond defects for the oxidized Si͑100͒ orientation. An important conclusion arising from this work is that the primary effect of an RTA in nitrogen ͑600-1050°C͒ is to cause hydrogen desorption from pre-existing P b0 / P b1 silicon dangling bond defects. The implications of this work to the study of the Si-SiO 2 interface, and the technological implications for silicon based MOS processes, are briefly discussed. The significance of these new results to thin oxide growth and optimization by RTO are also considered. Rights

This work examines the electrical activity of defects at the interface with Si͑100͒ for HfO 2 thin films ͑10-20 nm͒ deposited by injection metal oxide chemical vapor deposition. Based on an analysis of the capacitance-voltage response of gold/HfO 2 /Si(100) structures, two clear peaks are detected in the interface state density profiles, at specific energies in the lower (E v ϩ 0.22-0.28 eV͒ and upper (E v ϩ 0.93-0.97 eV͒ bandgap. The densities of defects responsible for these peaks have been calculated as 1.8-2.4 ϫ 10 12 and 7.3-9.1 ϫ 10 12 cm Ϫ2 , respectively. These defects are present when the HfO 2 films were deposited at sufficiently low temperatures (T р 350°C) to prevent hydrogen passivation. The density of interface defects was not significantly different for HfO 2 films deposited on native oxide or hydrogen-terminated silicon surfaces. The position of these defects in the silicon bandgap corresponds to the location of P b0 (/P b1 ) dangling bond defects in the thermally oxidized Si(100)/SiO 2 system. HfO 2 films deposited at 450°C did not exhibit the prominent interface defects observed on films deposited at T р 350°C, indicating hydrogen passivation during deposition.