scholarly journals Recent Developments on Silicon Carbide Thin Films for Piezoresistive Sensors Applications

10.5772/20332 ◽  
2011 ◽  
Author(s):  
Mariana Amorim ◽  
Rodrigo Savio ◽  
Homero Santiago ◽  
Marcos Massi
Keyword(s):  
Thin Films ◽  
Silicon Carbide ◽  
Piezoresistive Sensors ◽  
Recent Developments

Ambulatory Activity Monitoring

2009 ◽  
Vol 14 (2) ◽  
pp. 142-152 ◽  
Author(s):  
Johannes B.J. Bussmann ◽  
Ulrich W. Ebner-Priemer ◽  
Jochen Fahrenberg
Keyword(s):  
Physical Activity ◽  
Activity Monitoring ◽  
Main Stream ◽  
Computer Algorithms ◽  
Ambulatory Activity ◽  
Physiological Variables ◽  
Piezoresistive Sensors ◽  
Self Reports ◽  
Recent Developments ◽  
Objectively Measured

Behavior is central to psychology in almost any definition. Although observable activity is a core aspect of behavior, assessment strategies have tended to focus on emotional, cognitive, or physiological responses. When physical activity is assessed, it is done so mostly with questionnaires. Converging evidence of only a moderate association between self-reports of physical activity and objectively measured physical activity does raise questions about the validity of these self-reports. Ambulatory activity monitoring, defined as the measurement strategy to assess physical activity, posture, and movement patterns continuously in everyday life, has made major advances over the last decade and has considerable potential for further application in the assessment of observable activity, a core aspect of behavior. With new piezoresistive sensors and advanced computer algorithms, the objective measurement of physical activity, posture, and movement is much more easily achieved and measurement precision has improved tremendously. With this overview, we introduce to the reader some recent developments in ambulatory activity monitoring. We will elucidate the discrepancies between objective and subjective reports of activity, outline recent methodological developments, and offer the reader a framework for developing insight into the state of the art in ambulatory activity-monitoring technology, discuss methodological aspects of time-based design and psychometric properties, and demonstrate recent applications. Although not yet main stream, ambulatory activity monitoring – especially in combination with the simultaneous assessment of emotions, mood, or physiological variables – provides a comprehensive methodology for psychology because of its suitability for explaining behavior in context.

Thermodynamics and Microstructure Development in the Thin Film Reaction of Aluminum on Silicon Carbide

1995 ◽  
Vol 403 ◽  
Author(s):  
T. S. Hayes ◽  
F. T. Ray ◽  
K. P. Trumble ◽  
E. P. Kvam
Keyword(s):  
Thin Film ◽  
Thin Films ◽  
Silicon Carbide ◽  
Ohmic Contacts ◽  
Microstructure Development ◽  
P Type ◽  
Microstructural Studies

AbstractA refined thernodynamic analysis of the reaction between molen Al and SiC is presented. The calculations indicate much higher Si concentrations for saturation with respect to AkC 3 formation than previously reported. Preliminary microstructural studies confirm the formation of interfacial A14C3 for pure Al thin films on SiC reacted at 9000C. The implications of the calculations and experimental observations for the production of ohmic contacts to p-type SiC are discussed.

scholarly journals The Growth of Semiconductor Thin Films Studied by RHEED

1990 ◽  
Vol 43 (5) ◽  
pp. 583
Author(s):  
GL Price
Keyword(s):  
Thin Films ◽  
Surface Science ◽  
High Vacuum ◽  
High Energy ◽  
Ultra High Vacuum ◽  
Large Area ◽  
Growth Modes ◽  
Semiconductor Thin Films ◽  
Wide Range ◽  
Recent Developments

Recent developments in the growth of semiconductor thin films are reviewed. The emphasis is on growth by molecular beam epitaxy (MBE). Results obtained by reflection high energy electron diffraction (RHEED) are employed to describe the different kinds of growth processes and the types of materials which can be constructed. MBE is routinely capable of heterostructure growth to atomic precision with a wide range of materials including III-V, IV, II-VI semiconductors, metals, ceramics such as high Tc materials and organics. As the growth proceeds in ultra high vacuum, MBE can take advantage of surface science techniques such as Auger, RHEED and SIMS. RHEED is the essential in-situ probe since the final crystal quality is strongly dependent on the surface reconstruction during growth. RHEED can also be used to calibrate the growth rate, monitor growth kinetics, and distinguish between various growth modes. A major new area is lattice mismatched growth where attempts are being made to construct heterostructures between materials of different lattice constants such as GaAs on Si. Also described are the new techniques of migration enhanced epitaxy and tilted superlattice growth. Finally some comments are given On the means of preparing large area, thin samples for analysis by other techniques from MBE grown films using capping, etching and liftoff.

Structural relaxation of amorphous silicon carbide thin films in thermal annealing

2008 ◽  
Vol 516 (12) ◽  
pp. 3855-3861 ◽  
Author(s):  
Kun Xue ◽  
Li-Sha Niu ◽  
Hui-Ji Shi ◽  
Jiwen Liu
Keyword(s):  
Thin Films ◽  
Silicon Carbide ◽  
Amorphous Silicon ◽  
Thermal Annealing ◽  
Structural Relaxation ◽  
Amorphous Silicon Carbide

Effects of the Substrate on Piezoresistive Properties of Silicon Carbide Thin Films

2019 ◽  
Vol 44 (1) ◽  
pp. 1375-1380 ◽  
Author(s):  
Mariana A. Fraga ◽  
Humber Furlan ◽  
Luiz A. Rasia ◽  
Leandro L. Koberstein
Keyword(s):  
Thin Films ◽  
Silicon Carbide

DEPOSITION-AND-SUBSTRATE TUNABLE PHOTONIC BANDGAP IN OPTICAL RESPONSES OF HYDROGENATED AMORPHOUS SILICON CARBIDE THIN FILMS

2003 ◽  
Vol 17 (09) ◽  
pp. 387-392 ◽  
Author(s):  
NIKIFOR RAKOV ◽  
ARSHAD MAHMOOD ◽  
MUFEI XIAO
Keyword(s):  
Thin Films ◽  
Silicon Carbide ◽  
Photonic Bandgap ◽  
Visible Spectrum ◽  
Incoherent Light ◽  
Hydrogenated Silicon ◽  
Optical Responses ◽  
Amorphous Hydrogenated Silicon ◽  
The Status ◽  
Two Parameters

Amorphous hydrogenated silicon carbide (a-SiC:H) thin films have been prepared by the RF reactive magnetron sputtering technique. The optical properties of the films have been studied by optical spectroscopy with an incoherent light source. The material is commonly regarded as a dielectric. We have discovered however that some films that were prepared under certain deposition conditions and on certain substrates may respond to external light as a metallic thin film, i.e. there are strongly enhanced reflection peaks in the optical spectrum. We have further discovered that some films may have a strong and broadened absorption peak at about 590 nm, which is an apparent photonic bandgap in the visible spectrum. The appearance of the photonic bandgap is very sensitive to two parameters: the substrate and the deposition gas. By changing the two parameters, one shifts the status of the film from with and without the photonic bandgap.

scholarly journals The Study of Optical and Electrical Properties of Nanostructured Silicon Carbide Thin Films Grown by Pulsed-Laser Deposition

2021 ◽  
Vol 9 (2) ◽  
pp. 46-50
Author(s):  
Muhanad A. Ahmed ◽  
Mohammed F. Mohammed Sabri ◽  
Wathiq R. Abed
Keyword(s):  
Thin Film ◽  
Thin Films ◽  
Silicon Carbide ◽  
Absorption Coefficient ◽  
Pulsed Laser Deposition ◽  
Extinction Coefficient ◽  
Pulsed Laser ◽  
Laser Deposition ◽  
Cutoff Wavelength ◽  
Nanostructured Silicon

In this paper, nanostructured silicon carbide (SiC) thin films are deposited onto glass substrate using pulsed laser deposition technique. Electrical and optical characterizations such as conductivity, resistivity, transmission, Seeback effect, absorption, absorption coefficient, energy band gap, and extinction coefficient as a function of photon energy, and the effect of thin films thickness on transmission are carried out to characterize the prepared samples. Results showed that the prepared SiC thin film is an n-type semiconductor with an indirect bandgap of ~3 eV, 448 nm cutoff wavelength, 3.4395 × 104 cm−1 absorption coefficient and 0.154 extinction coefficient. The surface morphology of the SiC thin films is studied using scanning electron microscope at a substrate temperature of 400 °C and it is found that the grain size of the prepared SiC thin film is about 30 nm. As such, the nano thin films optical and structural characteristics enable the films to be used as gases sensors in many optoelectronic devices such as the environment and ultraviolet photodiode.

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