The construction of a normal-incidence imaging spectrophotometer for mapping of thin film properties is described. It is based on an on-axis reflective imaging system, utilising a telescope-like arrangement. A charge-coupled device camera is used as the detector, permitting measurements in the spectral range of 275–1100 nm with resolution of 37 µm. The performance of the instrument is demonstrated by optical characterisation of highly non-uniform thin films deposited from hexamethyldisiloxane on silicon substrates by a single capillary plasma jet at atmospheric pressure. The imaging spectrophotometry is used as a self-sufficient technique for the determination of both the film optical constants and maps of local thickness. The thickness maps are compared with the results of conventional thickness profile characterisation methods, profilometry and atomic force microscopy and the differences and errors are discussed.

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Epitaxial ZnSe thin films exhibiting two important defects, i.e., boundary roughness and thickness nonuniformity, prepared on GaAs substrates, are optically characterized using a combination of variable-angle spectroscopic ellipsometry, spectroscopic near-normal reflectometry, and imaging spectroscopic reflectometry (ISR). The influence of boundary roughness is incorporated into optical quantity formulas by the Rayleigh-Rice theory. Thickness nonuniformity is included using averaging of the unnormalized Mueller matrices. The dispersion model of the optical constants of the ZnSe films is based on parametrization of the joint density of electronic states. Very thin overlayers represented by thin films with identically rough boundaries are taken into account on the upper boundaries of the ZnSe films. Standard optical techniques are used to determine the spectral dependencies of the optical constants of the ZnSe films, together with the parameters of roughness and thickness nonuniformity. ISR is then used to find the maps of the local thickness and local rms value of height irregularities. The values of roughness parameters, determined using the standard techniques and ISR, are verified by a comparison with results obtained by atomic force microscopy.

a b s t r a c t a r t i c l e i n f oPlasma enhanced chemical vapor deposition (PECVD) from tetrakis(trimethylsilyloxy)silane (TTMS) has been studied at atmospheric pressure. TTMS has been chosen because of its unique 3D structure with potential to form nano-structured organosilicon polymers. Despite the widespread surveying of various silicon-organic molecules for PECVD, the use of TTMS in AP-PECVD has not been investigated deeper yet. PECVDs have been performed with two different plasma jets. While they are alike regarding the geometry and injection of TTMS, they differ in input power and excitation frequency. The radiofrequency plasma jet operates at lower power densities as compared to the microwave plasma jet. Despite this all the deposited films exhibit similar chemical properties resembling that of silicon dioxide (Si:O = 1:2) with carbon content below 5%. The films demonstrate a broad variety of morphologies from compact smooth films to nano-dendritic 3D structures depending on the particular process.

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