We have deposited thin films of SiO2 by remote plasma-enhanced chemical vapor deposition and have identified similar infrared (IR) spectroscopic signatures of Si–OH groups incorporated during either film growth, or the cooling down process in the deposition chamber. These films can also be hygroscopic and, on postdeposition exposure to atmospheric water vapor, they show changes in the IR spectra associated with the incorporation of additional Si–OH groups. These changes are (i) the development of a new symmetric feature, centered at about 3350 cm−1, within the asymmetric O–H stretching band generated during growth and/or cooling down; (ii) the development of a new spectral feature at 925 cm−1; and (iii) a shift in the Si–O bond-stretching band to higher wavenumber. We show that the first two changes in the IR spectra are due to near-neighbor Si–OH bonding groups that result from the reaction between water vapor and the Si–O–Si bonds of the SiO2 host network. These spatially correlated Si–OH groups have different spectral features, due to relatively strong hydrogen bonding interactions, from the randomly distributed Si–OH groups that are incorporated initially during film growth and/or cooling down. The shift in the frequency of the Si–O stretching band derives from a preferential reaction of water with strained and highly reactive Si–O–Si bonding groups, i.e., those with the smallest Si–O–Si bond angles which are attacked by water vapor, resulting in the formation of near–neighbor pairs of Si–OH bonding groups.

Amorphous carbon films grown with fluorohydrocarbons can be grown to have dielectric constant values around 2.0. The behavior of these films when subjected to thermal excursion is studied. We have investigated material deposited in an ECR plasma, and find that the F:H ratio of the gas mixture is a good guide to material properties. Films deposited at 5°C were placed in a vacuum chamber at 400°C as long as 60 minutes. The film thickness, dielectric constant, and infrared absorption spectrum change with the F:H ratio of the incoming gas and thermal cycling. It was found that the dielectric constant and loss tangent decrease upon heating and that there is an apparent increase in C=C groups. As expected, as the F:H ratio increases, the dielectric constant and thermal stability decrease. Good thermal stability is shown for F:H ratios of 1.5, which result in films with a dielectric constant of ∼2.4 after heating.

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Silicon nanocrystals have been fabricated by annealing amorphous hydrogenated silicon-rich oxynitride (SRON) films in vacuum for 4 h over the temperature range 850–1150 °C. X-ray photoelectron spectroscopy confirmed the composition of the film to be SiO0.17N0.07. Glancing angle x-ray diffraction results revealed consistent silicon crystallite sizes of  nm for films annealed at temperatures , increasing to  nm for films annealed at 1150 °C. The room temperature photoluminescence spectra of the samples annealed at 850 and 950 °C comprised luminescent peaks from silicon nanocrystals and luminescence from the defects in Si–O system. However, only peaks from defects in Si–O system were present in the luminescence spectra from samples annealed at temperatures greater than 950 °C. For the samples annealed at 850 and 950 °C, the presence of strong Si–N bonds prevented the coalescence of smaller silicon crystallites into larger crystallites. Larger, non-luminescent silicon crystallites were only formed in films annealed at temperatures greater than 950 °C, where the energetics of coalescing particles overcame the strong Si–N bonding in SRON films. High-resolution transmission electron microscopy analysis confirmed the presence of silicon nanocrystallites. A proposed growth mechanism of silicon nanocrystals is discussed.

The need to substitute SiO2 with low dielectric constant (κ) materials increases with each complementary metal–oxide–semiconductor process generation as interconnect RC delay, crosstalk, and power dissipation play an ever larger role in high-performance integrated circuits. Fluorinated amorphous carbon films (a-C:F,H) with low-κ properties (κ∼2.0–2.4) deposited by plasma-assisted chemical vapor deposition (CVD) techniques provide several advantages including low temperature processing, good gap fill capabilities, minimal moisture absorption, and simple implementation. Several deposition techniques have been examined, including high-density plasma and parallel-plate plasma-assisted CVD. In each case, it is possible to deposit a-C:F,H films with widely varying properties, such as κ and thermal stability. This has led to a good deal of confusion as to what is required to produce useful material. Results from many different sources are examined to develop a coherent picture of the relationships between deposition techniques, microstructural features, and macroscopic properties, and to summarize the scientific and technical challenges that remain for a-C:F,H implementation. The relationships between film deposition parameters such as applied substrate bias and film properties are presented in the discussion. In addition, x-ray photoelectron spectroscopy and network constraint theory are used to develop connections between microstructural and macroscopic properties, as well as to show how deposition parameters can be used to create a predictive model. This will demonstrate what process parameters are important in film formation. Finally, efforts to incorporate this material into integrated circuits, as well as measurements of the reliability and performance will be reviewed.