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A microplasma printer is employed to deposit thin film patterns of TiO2 by titanium tetra‐isopropoxide and N2/O2 plasma at atmospheric pressure. The setup is adopted to carry out deposition in two configurations, namely under chemical vapor deposition (CVD) and atomic layer deposition (ALD) modes. The properties of TiO2, as well as the patterning resolution, are investigated. The amorphous TiO2 deposited in the CVD mode contains a relatively high level of impurities (residual carbon content of 5–10 at.%) and is characterized by a low refractive index of 1.8. With the ALD mode on the other hand, TiO2 is obtained with a low level of impurities (<1 at.% C and <2 at.% N), a refractive index of 1.98, and a growth per cycle of 0.15 nm. Furthermore, the spatial resolution for a 8‐nm‐thick film is determined by X‐ray photoelectron spectroscopy line scan and found to be equal to 2,000 and 900 µm for the CVD and ALD modes, respectively. This study can be regarded as the first step toward area‐selective CVD and ALD of TiO2 by a microplasma printer, which can be further explored and extended to other material systems. [ABSTRACT FROM AUTHOR]

This paper reports on the experimental study of the dynamic evolution of a dielectric barrier discharge in an atmospheric-pressure plasma enhanced chemical vapor deposition reactor using a gated intensified charge coupled detector. It is observed that a diffuse atmospheric pressure glow is formed via transition from Townsend-like discharge or, alternatively, can be initiated by a filamentary discharge. The formation of the glow current spot is followed by the lateral expansion of the discharge. [ABSTRACT FROM AUTHOR]

Organosilicon layers have been deposited from 1,3,5-trivinyl-1,3,5-trimethylcyclotrisiloxane (V3D3) by means of the initiated-chemical vapor deposition (i-CVD) technique in a deposition setup, ad hoc designed for the engineering of multilayer moisture permeation barriers. The application of Fourier transform infrared (FTIR) spectroscopy shows that the polymerization proceeds through the scission of the vinyl bond and allows quantifying the degree of conversion of vinyl groups, which is found to be larger than 80% for all the deposited layers. In situ real-time spectroscopic ellipsometry (SE) allows following all the i-CVD growth stages, i.e., from the initial monomer adsorption to the layer bulk growth. Finally, the combination of SE and FTIR has allowed defining the process window for the deposition of stable and highly cross-linked poly(V3D3) layers by tuning a key process parameter, i.e. the surface monomer adsorption. [ABSTRACT FROM AUTHOR]

Abstract: Although very promising results in terms of moisture and oxygen barrier properties have been achieved by alternating organic and inorganic layers composing a multilayer structure, the impact of the organic interlayer on the global barrier performance is still unraveled. Three main hypotheses have been reported in literature so far, although consistently applied to the case of a liquid-phase polymerization process of the organic layer: smoothening of the polymeric substrate surface by the organic layer; decoupling, by means of a tortuous path, of the defects present in two adjacent inorganic barrier layers; filling of the nano-defects present in the barrier layer during the (liquid phase) polymerization of the organic layer. Within this framework, this contribution reports on the adsorption/desorption study of an initiated-CVD (i-CVD) monomer (trimethyl-trivinyl-cyclotrisiloxane), V3D3, performed on plasma deposited SiO2-like layers by means of in situ spectroscopic ellipsometry measurements. The SiO2-like layers are used as moisture permeation barriers followed by an organic interlayer deposited by means of the i-CVD technique. The experimental evidence for the V3D3 molecule infiltration and filling in the open micro/meso porosity present in the inorganic layer underneath, confirms the hypothesis on the filling of nano-defects in the barrier layer upon organic layer deposition and shows that the defect filling occurs also in the case of a CVD-based approach. [Copyright &y& Elsevier]