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Research is presented concerning the use of Fourier transform infrared spectroscopy to investigate the characteristics of ultrathin silicon oxide films. The films were thermally grown on Si (100).

Rapid thermal oxidation of Si in ozone gas is studied by using in situ mirror enhanced reflection Fourier transform infrared (IR) spectroscopy at temperatures between 200 and 550 degreeC. The oxidation rate in ozone is found to be comparable to the one in pure oxygen at approximately 200 degree C higher temperature.

A new study aims to understand the effect of temperature on low temperature ozone oxidation of silicon germanium alloys.

Research was conducted to examine the various processing sequences to derive a bimodal N concentration profile with one peak close to the dielectric/Si interface and the other near the top surface of the dielectric. Suggestions on how to optimize the amount and concentration profile of the incorporated N by the use of process-property relationships are presented. An investigation of the N incorporation was also performed.

Thin films of hafnium oxide are deposited on Si(100) substrates by means of atomic layer deposition using tetrakis(diethylamino)hafnium and water on Si(100) at 300 °C. Detailed studies of temperature induced annealing effects on the HfO2/Si interface are done using angle resolved x-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectroscopy, and time of flight secondary ion mass spectroscopy (ToF-SIMS). As-deposited films show mostly native silicon oxide at the interface. Crystallization of HfO2 film initiates at about 600 °C. As the annealing temperature is increased, the hafnium silicate content in the film is found to increase and the mostly silicon oxide interlayer is found to grow thicker under Ar atmosphere. Also, the formation of hafnium silicide is found to take place at temperatures >=800 °C. The XPS data shows decomposition of the interfacial hafnium silicate layer into hafnium oxide and silicon oxide at 1000 °C along with increasing formation of hafnium silicide. The ToF-SIMS data suggest interdiffusion of the hafnium oxide film and the interfacial silicon oxide during the annealing process. [ABSTRACT FROM AUTHOR]

Low temperature, nitric oxide (NO)/nitrous oxide (N[sub 2]O) aided, sub-35 Å Si[sub 0.85]Ge[sub 0.15] oxynitrides have been grown at 550 and 650 °C, while the oxynitridation feed gases have been preheated to 900 and 1000 °C, respectively, before entering the reaction zone. X-ray photoelectron spectroscopy and secondary ion mass spectroscopy (SIMS) data suggest that NO-assisted oxynitridation incorporates more nitrogen than the N[sub 2]O-assisted one, while there is minimal Ge segregation towards the dielectric/substrate interface in both oxynitridation processes. Moreover, SIMS results suggest that nitrogen is distributed throughout the film in contrast to high temperature Si oxynitridation, where nitrogen incorporation takes place near the dielectric/substrate interface. Z-contrast imaging with scanning transmission electron microscopy shows that the oxynitride grown in NO at 650 °C has a sharp interface with the bulk Si[sub 0.85]Ge[sub 0.15], while the roughness of the dielectric/Si[sub 0.85]Ge[sub 0.15] substrate interface is less than 2 Å. These results are discussed in the context of an overall mechanism of SiGe oxynitridation. [ABSTRACT FROM AUTHOR]

The chemical kinetics and process-structure relationships of silicon oxynitride films grown in nitric oxide (NO) ambient at 900-1000 °C are studied in flow reactor systems. Residual gas analyses at the reactor exit suggest that no detectable gas phase decomposition of NO takes place at these conditions. Two regions, one nitrogen-depleted (near the top dielectric surface) and one nitrogen-rich (near the dielectric/substrate interface), are considered within the dielectric film, based on reported secondary ion mass spectrometric and angled resolved x-ray photoelectron spectroscopic data. Nitrogen removal reactions are accounted for in the nitrogen-rich layer, while nitrogen incorporation reactions are considered at the dielectric/substrate interface. The diffusion-reaction growth rate model makes use of literature values for the solid-state diffusivities, reaction rate constants, and fraction of the nitrogen-rich layer. The model predictions are found to be in good agreement with all trends of the experimental data at the conditions investigated. [ABSTRACT FROM AUTHOR]

Ultrathin silicon oxide films thermally grown on Si (100) are characterized with mirror-enhanced polarized reflectance Fourier transform infrared spectroscopy (MEPR-FTIR). MEPR-FTIR is proposed to effectively probe properties of ultrathin films. Using a mirror and a polarizer, MEPR-FTIR overcomes the difficulty of weak IR intensities normally encountered in ultrathin gate dielectrics such as SiO[sub 2]; the intensity of the silicon oxide longitudinal optical (LO) mode is found to increase by a factor of about 20. Therefore, FTIR spectrometers with sensitivity down to 0.01% may allow even submonolayer probing of silicon oxide on Si substrates. The relationship between film thickness and IR intensity of the LO mode at 1252 cm-1 is presented for silicon oxide films as thin as a few Å thick. Independent measurements with ellipsometry, cross-sectional transmission electron microscopy, and x-ray photoelectron spectroscopy as well as theoretical predictions using the general Fresnel function are utilized. Although nonlinear overall, the theoretically predicted relationship between the MEPR-FTIR intensity and film thickness is almost linear within the range 0-50 Å. Experimental data are shown to agree very well with the theoretical calculations for two different kinds of oxides: thermal oxides grown at 1050 °C and native oxides. Such results suggest that the MEPR-FTIR can be useful as an ex situ or in situ technique for thickness measurements and, in fact, for other properties of ultrathin gate dielectrics. © 2001 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Presents a mathematical model of transport phenomena and epitaxial silicon growth in a pancake chemical vapor deposition reactor for SiH[sub2]Cl[sub2]-H[sub2]HCl system. Equations for cylindrical coordinates; Chemical formulas for gas-phase reactions, adsorption, desorption and surface reactions; Description of gas flow patterns.