Effect of Temperature Ramp Rate on the Morphology, Phase and Adhesion Strength of Ag-Ta2O5 Thin Film

In the present work we have reported the effect of temperature on the gas sensing properties of pure Polyaniline (PANI) and Multiwall carbon nanotube (MWNT) doped PANI composite thin film based chemiresistor type gas sensors for hydrogen gas sensing application. PANI and MWNT doped PANI composite were synthesized by in situ chemical oxidative polymerization of aniline using ammonium persulfate in an acidic medium. The thin sensing film of chemically synthesized PANI and MWNT doped PANI composite were deposited onto finger type Cu-interdigited electrodes using spin cast technique to prepared chemiresistor type gas sensor. The electrical properties of these composite thin films were characterized by I-V measurements as function of temperature. The I-V measurement revealed that conductivity of composite thin films increased as the temperature increased. The changes in resistance of the composite thin film sensor were utilized for detection of hydrogen gas. It was observed that at room temperature, MWNT doped PANI composite sensor shows higher response value and sensitivity with good repeatability in comparison to pure PANI thin film sensor. It was also observed that both PANI and MWNT doped PANI composite thin film based sensors showed unstable behavior as the temperature increased. The surface morphology of these composite thin films has also been characterized by scanning electron microscopy (SEM) measurement.

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New method to improve the adhesion strength of tungsten thin film on silicon by W2N glue layer

Applied Physics Letters ◽

10.1063/1.107880 ◽

1992 ◽

Vol 61 (5) ◽

pp. 537-539 ◽

Cited By ~ 24

Author(s):

Yong Tae Kim ◽

Chang Woo Lee ◽

Suk‐Ki Min

Keyword(s):

Thin Film ◽

Adhesion Strength ◽

New Method

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A Study of Non-Infrared-Active Hydrogen Bonding in a-Si:H Thin Film using combined Calibrated Temperature Desorption Spectroscopy and FTIR

MRS Proceedings ◽

10.1557/proc-609-a26.3 ◽

2000 ◽

Vol 609 ◽

Author(s):

DJ. Santjojo ◽

J.C.L. Cornish ◽

M.O.G. Talukder

Keyword(s):

Thin Film ◽

Thin Films ◽

Hydrogen Bonding ◽

Hydrogenated Amorphous Silicon ◽

Active Hydrogen ◽

Linear Temperature ◽

Silicon Thin Films ◽

Temperature Ramp ◽

Hydrogenated Amorphous ◽

Hydrogen Effusion

ABSTRACTNon-infrared-active hydrogen bonding species were investigated by analyzing the infrared spectra and the calibrated temperature desorption spectroscopy (CTDS) spectra of hydrogen released during degassing of hydrogenated amorphous silicon thin films. Samples were degassed gradually using a linear temperature ramp (0.5°C/s). Each stage corresponds to a temperature at which the hydrogen effusion peaks can be found (~ 340°C, ~ 500°C and ~ 610°C). Differences in the amounts of hydrogen obtained from the FTIR spectra and the CTDS measurement correspond to the non-infrared-active, occluded hydrogen.

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Impact of process conditions on chemical solution deposited BNKT thin film electromechanical properties

SN Applied Sciences ◽

10.1007/s42452-021-04692-4 ◽

2021 ◽

Vol 3 (10) ◽

Author(s):

Kyle M. Grove ◽

Austin Fox ◽

David P. Cann ◽

Song Won Ko ◽

Peter Mardilovich ◽

...

Keyword(s):

Thin Film ◽

Thin Films ◽

Dielectric Constant ◽

Dielectric Loss ◽

Pyrolysis Temperature ◽

Piezoelectric Response ◽

Excess Properties ◽

Process Conditions ◽

Chemical Solution ◽

Ramp Rate

Abstract Phase pure perovskite (1-x)Bi1/2Na1/2TiO3 – xBi1/2K1/2TiO3 (BNKT) thin films were successfully prepared via an inverse mixing order chemical solution deposition method and the impact of process conditions on film properties were observed. Process conditions evaluated included crystallization temperature and time, ramp rate, pyrolysis temperature, and cation excess. Properties measured included crystal structure, dielectric constant, dielectric loss, piezoelectric response, and ferroelectric response. A few notable trends were observed. A subtle impact on piezoelectric response was observed in films prepared using different ramp rates: 100 C per second films (d33,f = 60 ± 5 pm/V at 1 kHz), 75 °C per second films (d33,f = 55 ± 5 pm/V) and 150 C per second films (d33,f = 50 ± 5 pm/V). Films prepared using a 75 °C per second ramp rate displayed slightly higher dielectric loss (tan δ = 0.09 at 1 kHz) than films prepared using a 100 °C per second ramp rate (tan δ = 0.07 at 1 kHz) or 150 °C per second ramp rate (tan δ = 0.05 at 1 kHz). Pyrolysis temperatures greater than 350 °C are necessary to burn off organics and maximize film dielectric constant. Dielectric constant increased from 450 ± 50 at 1 kHz to 600 ± 50 at 1 kHz by increasing pyrolysis temperature from 300 to 400 °C. Excess cation amounts (for compositional control) were also evaluated and it was found films with higher amounts of Na and K excess compared to bismuth excess displayed an increase in d33,f of about 10 pm/V compared to films prepared with equivalent Bi and Na and K excess amounts. Article highlights Impact of processing conditions on inverse mixing order chemical solution deposited bismuth based thin films. Dielectric, piezoelectric, and ferroelectric properties of thin film bismuth sodium titanate-bismuth potassium titanate thin films. Developing lead-free piezoelectric actuator materials.

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Stresses in a Multilayer Thin Film/Substrate System Subjected to Nonuniform Temperature

Journal of Applied Mechanics ◽

10.1115/1.2755178 ◽

2008 ◽

Vol 75 (2) ◽

Cited By ~ 33

Author(s):

X. Feng ◽

Y. Huang ◽

A. J. Rosakis

Keyword(s):

Thin Film ◽

Field Measurements ◽

Film Stress ◽

Effect Of Temperature ◽

Multilayer Thin Film ◽

Nonuniform Temperature ◽

Curvature Invariant ◽

Full Field ◽

Curvature Measurements ◽

Film Substrate

Current methodologies used for the inference of thin film stress through curvature measurements are strictly restricted to uniform film stress and system curvature states over the entire system of a single thin film on a substrate. By considering a circular multilayer thin film/substrate system subjected to nonuniform temperature distributions, we derive relations between the stresses in each film and temperature, and between the system curvatures and temperature. These relations featured a “local” part that involves a direct dependence of the stress or curvature components on the temperature at the same point, and a “nonlocal” part, which reflects the effect of temperature of other points on the location of scrutiny. We also derive relations between the film stresses in each film and the system curvatures, which allow for the experimental inference of such stresses from full-field curvature measurements in the presence of arbitrary nonuniformities. These relations also feature a “nonlocal” dependence on curvatures making full-field measurements of curvature a necessity for the correct inference of stress. The interfacial shear tractions between the films and between the film and substrate are proportional to the gradient of the first curvature invariant, and can also be inferred experimentally.

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