Evidence for the precursors of nitrided silicon in the early stages of silicon oxynitridation in N2:N2O atmosphere

Abstract

Nitridation of hydrogen-terminated silicon with N2:N2O has been studied by x-ray photoemission spectroscopy. Our analysis has given evidence that the broad N(1s) peak at 398–399 eV, usually reported in the literature, is preceded by the formation of a narrow peak at 397.5 eV, attributed to the moiety Si3N in which silicon is only marginally oxidized, and two other peaks at 400.0 eV and 401.5 eV, attributed to the moieties Si2NOSi and SiNO, respectively.

On the scaling issues and high-κ replacement of ultrathin gate dielectrics for nanoscale MOS transistors

“…It was further found with X-ray photoelectron spectroscopy (XPS) that the total nitrogen surface concentration of the prepared ''oxynitride'' is about (3 ± 1) · 10 14 cm À2 . This amount is close to the surface density of a half monolayer of solid and is close to the values of other reports [108][109][110][111][112]. The distribution of nitrogen atoms are mainly found at the Si/dielectric interface and it was believed that the nitrogen incorporation is made mainly via the chemical reaction with the interface Si-Si bonds [105,111], i.e.…”

Si 2p XPS spectrum of the hydrogen‐terminated (100) surface of device‐quality silicon

“…Operated with a monochromatized beam (photon energy D 1486.6 eV) and a pass energy of 2.95 eV, the spectrometer had an energy resolution of ¾0.2 eV. 7,8 This value was attributed by assuming that the experimental width of the Si 2p 3/2 peak (0.35 eV) results from the quadratic composition of the physical width (0.28 eV) 9 with the instrumental resolution of our apparatus. Actually the results of this work (reported in the following) attributing an experimental width of 0.30 eV to elemental silicon show that this estimate must be corrected slightly to a lower value.…”

“…7,8 We decided thus to attack the problem of determining the in-depth distribution of silicon bonded to hydrogen in device-quality (100) surfaces, prepared via HF aq etching and subsequent exposure to H 2 at high temperature, by measurements at different take-off angles of the Si 2p spectrum.…”

Accounting for anomalous oxidation states of silicon at the Si/SiO2 interface

“…Evolution of the spectra is discussed elsewhere. 9 Nitridation by N 2 alone was observed, prolonging the purge phase: an exposure to N 2 at 850°C for 50 s produced the growth of an N 1s peak of intensity <10% of that produced by exposure to N 2 O for 10 s. The N 1s peak resulting after exposure to pure N 2 was centred on an energy of 397-398 eV, corresponding to nitrogen in Si 3 N configuration.…”