Various planar technologies are employed for developing solid-state sensors having low cost, small size and high reproducibility; thinand thick-film technologies are most suitable for such productions. Screen-printing is especially suitable due to its simplicity, low-cost, high reproducibility and efficiency in large-scale production. This technology enables the deposition of a thick layer and ...

Highly sensitive H2 gas sensors were prepared using pure and Pt-loaded SnO2 nanoparticles. Thick film sensors (~35 μm) were fabricated that showed a highly porous interconnected structure made of high density small grained nanoparticles. Using Pt as catalyst improved sensor response and reduced the operating temperature for achieving high sensitivity because of the negative temperature coeffici...

Amorphous titanium dioxide-coated carbon nanotubes (CNTs) were prepared by atomic layer deposition (ALD) and investigated as sensing layers for resistive NO2 and O2 gas sensors. By varying ALD process conditions and CNT structure, heterostructures with different metal oxide grain size, morphology and coating thickness were synthesized. Higher responses were observed with homogeneous and continu...

Thick films of AR Grade nano Fe2O3 material with n-type semiconducting properties were prepared and tested for their gas sensing performances. Thick films of the materials were prepared by screen printing technique. The gas sensing performance was studied using static gas sensing system. The material was tested for various gases such as CO, CO2, NH3, Cl2, H2, LPG, ethanol and H2S. The nano Fe2O...

Traditional methods of synthesis of metal-oxide gas sensing materials for semiconductor sensors are based on wet sol-gel processes. However, these processes lead to the formation of hydroxyl groups on the surface of oxide particles being responsible for the strong response of a sensing material to humidity. In this work, we investigated the possibility to synthesize metal-oxide materials with r...

Porous nano and micro crystalline tin oxide films were deposited by RF Magnetron Sputtering and doctor blade techniques, respectively. Electrical resistance and impedance spectroscopy measurements, as a function of temperature and atmosphere, were performed in order to determine the influence of the microstructure and working conditions over the electrical response of the sensors. The conductiv...

Macroporous SnO2 (mp-SnO2(P-n); P means polymethylmethacrylate (PMMA) and n = diameter of PMMA microsphere) thick film gas sensors were fabricated by a modified sol-gel method by employing PMMA microspheres (n = 800, 400, 250 and 150 nm) as a template and SnCl2 as a tin source. Morphology of mp-SnO2 films was markedly dependent on the SnCl2 concentration and the diameter of PMMA microspheres. E...

We are developing large-area, thick, structured CsI(Tl) imaging sensors for a wide variety of X-ray imaging applications. Recently we have fabricated structured CsI(Tl) scintillators ranging from 30 μm (16 mg/cm) to 2000 μm (900 mg/cm) in thickness and up to 15 x 15 cm in area. Even 2000-μm-thick film showed well-controlled columnar growth throughout the film. Material characterization confirme...