Oxynitride films grown on preoxidized (100) silicon surfaces in a nitric oxide (NO) ambient at 950 °C have been investigated using x-ray photoelectron spectroscopy (XPS), secondary ion mass spectrometry (SIMS), atomic force microscopy (AFM), and cross-sectional transmission electron microscopy (XTEM). Compared to N2O oxynitride, NO oxynitride exhibits very different surface chemistry, interface properties, and growth mechanisms. The etch back of NO and N2O oxynitride films allows control of sample thickness for the XPS measurements. NO oxynitride has the interfacial nitrogen (Nint) sharply peaked on the Si substrate side of the interface, while it is broad and on the dielectric side of the interface for the N2O oxynitride. The N(1s) XPS results reveal a clear distinction between N2O oxynitride and NO oxynitride. Near the Si/dielectric interface the NO oxynitride shows primarily Si≡N bonds, while the N2O films showed a N(1s) binding energy peak that is in-between that of Si≡N bonds and Si2=N—O bonds. Furthermore, the NO oxynitride surface roughness as determined by AFM is lower than that of the Si/SiO2 interface.

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Nitrogen profile effects on the growth rate of gate oxides grown on nitrogen-implanted silicon

A dual-gun reactive ion beam sputtering technique has been used to reproducibly fabricate Al2O3 dielectrics with low electrical loss for controlled thickness ranging from approximately 10 to 360 Å. The linear dependence of the reciprocal capacitance on dielectric thickness of Al-Al2O3-Al trilayer structures incorporating this dielectric reveals a significant contribution from an interfacial capacitance in series with the geometric capacitance. Room-temperature measurements of both the dc resistance and the frequency-dependent complex impedance demonstrate that, with respect to bulk, there is an enhanced frequency-dependent dielectric loss associated with this interfacial capacitance.

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