X-ray photoelectron spectroscopy study on SiO2/Si interface structures formed by three kinds of atomic oxygen at 300 °C

Abstract

Using the high-brilliant synchrotron radiation at SPring-8 we have studied the SiO2/Si interface structures, the interface state densities, and the uniformities of ∼1-nm-thick oxide films formed by three kinds of atomic oxygen at 300 °C by measuring Si 2p photoelectron spectra at the photon energy of 1050 eV and the energy loss spectra of O 1s photoelectrons at the photon energy of 714 eV. Among silicon oxide films studied here the abrupt compositional transition at SiO2/Si interface, the smallest deviation in interface state density, the interface state density comparable to that for thermal oxide formed in dry oxygen at 950 °C, and the highest uniformity was obtained with oxide film formed in krypton-mixed oxygen (Kr:O2=97:3) plasma.

Detection of defect states in low-k dielectrics using reflection electron energy loss spectroscopy

“…Linear extrapolation of the leading edge of the loss spectrum for the as-loaded film, indicates a surface band gap of 8.8 eV. This value is consistent with both other REELS [43][44][45][46][47][48][49] and optical 50,51 bandgap measurements for a variety of a-SiO 2 surfaces and thin film/bulk materials. However after Ar þ sputtering, the apparent band gap of the a-SiO 2 surface decreases slightly and two distinct peaks appear in the loss spectrum at 5.0 and 7.2 eV, respectively.…”

“…-49 These defects have been attributed to surface oxygen vacancies (SOV) analogous to the oxygen deficient centers (ODC)/silicon dangling bond (E') centers observed in bulk SiO 2 [44][45][46][47][48][49]. This assignment by previous authors was based on several observations.…”

Characterization of oxide films on 4H-SiC epitaxial (0001¯) faces by high-energy-resolution photoemission spectroscopy: Comparison between wet and dry oxidation

“…The areal density of the compositional transition states, N n , can be estimated from the Si 2p photoelectron spectra at a photoelectron take-off angle of 55°, where the effect of elastic scattering can be effectively neglected, 32 by using the following relation: 33,34 …”

“…However, it has been reported that in the case wherein SiO 2 -Si structures are exposed to atomic hydrogen, the interface states detected electrically are not reduced well by hydrogen termination of silicon dangling bonds 38 and the interface states relate closely to the compositional transition structure. 34 Therefore, the reduction in the areal density of the compositional transition states for wet oxidation is a promising candidate as the cause for the reduction in the interface states.…”

Electric characteristics of Si3N4 films formed by directly radical nitridation on Si (110) and Si (100) surfaces.

“…(110) surface. It has been reported that the interface states density in MOS device has been related to the quantities of interface transition region [7]. We consider that the Si 3 N 4 gate insulator formed on Si (110) have the high quality interface characteristics for low intermediate nitridation states density.…”