ZnO nanoparticles were produced by flame spray pyrolysis (FSP) using zinc naphthenate as a precursor dissolved in toluene/acetonitrile (80/20 vol%). The particle properties were analyzed by XRD, BET, and HR-TEM. The sensing films were produced by mixing the particles into an organic paste composed of terpineol and ethyl cellulose as a vehicle binder and were fabricated by doctor-blade technique...

Analyte sensitivity for gas sensors based on semiconducting metal oxides should be highly dependent on the film thickness, particularly when that thickness is on the order of the Debye length. This thickness dependence has previously been demonstrated for SnO₂ and inferred for TiO₂. In this paper, TiO₂ thin films have been prepared by Atomic Layer Deposition (ALD) using titanium isopropoxide an...

We have investigated electron energy relaxation in copper wires with several film thicknesses (t=14-90 nm) evaporated on (a) 30 nm thick suspended silicon nitride membranes, and (b) bulk nitridized substrates. The experiment was performed at sub-Kelvin temperatures by heating the electron gas by current, and measuring the resulting temperature rise using sensitive normal metal-insulator-superco...

In this work, a PdNi thin film hydrogen gas sensor with integrated Pt thin film temperature sensor was designed and fabricated using the micro-electro-mechanical system (MEMS) process. The integrated sensors consist of two resistors: the former, based on Pt film, is used as a temperature sensor, while the latter had the function of hydrogen sensing and is based on PdNi alloy film. The temperatu...

Doctor of Philosophy ALGORITHMS FOR SENSOR VALIDATION AND MULTISENSOR FUSION by Sean James Wellington Existing techniques for sensor validation and sensor fusion are often based on analytical sensor models. Such models can be arbitrarily complex and consequently Gaussian distributions are often assumed, generally with a detrimental effect on overall system performance. A holistic approach has t...

This paper presents the experimental results of utilizing a flexible thin-film membrane as a passive barrier to radon gas diffusion. Nine commercially available membranes of various compositions and thicknesses were evaluated as retardant to radon gas diffusion. The radon gas concentration ratios across the thin-film membranes alone and in combination with an adjacent concrete sample (effective...

In this work we have fabricated hydrogen gas sensors based on undoped and 1 wt% multi-walled carbon nanotube (MWCNT)-doped tungsten oxide (WO(3)) thin films by means of the powder mixing and electron beam (E-beam) evaporation technique. Hydrogen sensing properties of the thin films have been investigated at different operating temperatures and gas concentrations ranging from 100 ppm to 50,000 p...

10 The influence of structure, phase composition, system dispersity and particle morphology of Fe2O3and In2O3-based thin film layers on the electrical parameters of the corresponding gas sensors was studied in this paper. High selectivity and sensitivity of heterostructural -Fe2O3/In2O3 thin film sensors in the detection of alcohols has been here established. As it was found, the above mentione...

This work presents the fabrication of thermopiles with high output voltage. A series of mixed thick/thin-film thermopiles were performed – one of the arms of the thermocouples was screen-printed (PdAgor Ag-based thick-film layers), the second was made of magnetron sputtered semiconductor (compositions based on Ge). The output parameters (thermoelectric force ET [V], internal resistance Ri [Ω], ...