Andy Hooper

Nitrogen-doped plasma enhanced chemical vapor deposited (PECVD) amorphous carbon: processes and properties

In this work we discuss thin film amorphous carbon, which is deposited in a dual frequency, plasma enhanced chemical vapor deposition (PECVD) system in such a manner that it contains a small amount of nitrogen. Unlike most carbon films deposited using PECVD, the films in this study were deposited on the grounded electrode and therefore, subject to little energetic bombardment during growth. Methane was used as the carbon-containing precursor. We illustrate some potential applications for this type of film and discuss the effect of various process parameters on resultant film properties such as optical constants, resistivity, stoichiometry, and chemical bonding and structure.

Measuring the thickness of organic/polymer/biological films on glass substrates using spectroscopic ellipsometry

In this work we discuss a method of determining film thickness for film/substrate combination where the index of refraction of the film and substrate in the transparent spectral regions is almost identical. Common examples of this situation are organic/polymer/biological films on glass substrates. Infrared ellipsometry is used and we use weight gain to provide some necessary additional information for determining the optical functions for the film material. The spectral regions of strong molecular vibrations are then used for determining film thickness.

Nucleation and Growth of Vapor-Deposited Metal Films on Self-Assembled Monolayers Studied by Multiple Characterization Probes

The underlying chemistry of the interaction of metal atoms with organic thin films and polymer surfaces has important implications in many areas of science and technology but uncovering critical details of the mechanisms has been difficult, primarily because of the lack of well-defined organic surfaces. Self-assembled monolayers (SAMs)1–3 can now provide an approach to overcoming this problem.4–15 However, in order to fully utilize these precision surfaces it is also necessary to utilize combinations of surface science techniques that can reveal information about both the nature of the metal atoms and the organic surface chemistry and structure.

Effect of annealing temperature on physical properties of thin epitaxial PZT films on STO/Si substrates

In this work, we report the effect of annealing temperature on the properties of epitaxial PbZr0.52Ti0.48O3 (PZT) films deposited using sol-gel techniques on (001) Si substrates with a thin, epitaxial SrTiO3 (STO) interlayer. The STO is grown on silicon using molecular beam epitaxy (MBE) and acts as the template for PZT growth. We report the values for stress, density, thickness, and refractive index vs. anneal temperatures for a thin PZT film. AFM surface roughness values of less than 0.4 nm are typical for this film. XRD patterns show the film to be c-axis orientated, with PHI scans demonstrating that the [100] PZT is orientated along the [110] Si direction. SEM cross-sections show the film morphology is free of gain boundaries and are clear of interfacial layers from the multiple spin/bake/anneal deposition technique, thereby making this material an excellent candidate for electro-optic applications.

Nitrogen-doped plasma-enhanced CVD amorphous carbon: processes and properties

In this work we discuss thin film amorphous carbon which is deposited in a dual frequency plasma enhanced CVD system with a nitrogen-containing ambient. Unlike most carbon films deposited using PECVD, the films in this study were deposited on the grounded electrode and therefore subject to little energetic bombardment during growth. Methane was used as the carbon-containing precursor. We illustrate some potential applications for this type of film and discuss the effect of various process parameters on resulting film properties, such as optical constants, stoichiometry, and chemical bonding and structure.