1,721,046 research outputs found
Sensori e trasduttori a film spesso
No full textE' riportata una rassegna riguardante sensori a film spesso e tecnologia a film spesso. Essa intende illustrare conoscenze e processi sviluppati in attività che coprono un arco di tempo poco più che decennale ma in rapida, crescente espansione
Thick-film sensors: an overview
No full textSensors form a vital part of any measurement and control system,. Demand for sensors generally are increasing, but particularly for rugged, reliable, integrated sensors for computer control systems.Among the various sensor technologies, thick-film technology (TFT) does not really offer conceptually new sophisticated solutions, but does offer several appreciale capabilities, e. g., flexibility in chice of materials and design, easy integration with electronic circuits and packaging.This paer illustrates some specific features of TFT for sensor manufacture and overviews most of the types of devices used or developed at present. Moreover, some new sensors, which might be conceived and developed in the near future, are suggested
Sensori termoresistivi:un po' di fisica e tanta fantasia
No full textViene descritto l'effetto termoresistivo e considerato il suo impiego nell'area dei sensori. Sono descritti inoltre i materiali e le tecniche di realizzazione di realizzaione di sensori insieme con esempi di dispositivi per la misura di temperatura, flusso e controllo di grandezze elettriche e fisiche
Evolution of microstructure and performance of Pd/Ag-based thick-film conductors
No full textPd/Ag based inks are probably the most commonly used conductors in thick-film hybrid technology. The evolution of microsctructure of these films was studied on samples fired with isochronal cycles at a peak temperature in the range from 300 C to 850 C. The samples were investigated by means of X-ray diffraction, SEM amd EDAX analysis techiques; the results of these analises as well as those of thermogravimetry (TG, DTG) and differential thermal analysis (DTA), enable one to obtain a clear picture of the complex evolution of microstructure of these conductors, which correlates quite strictly with the performance of the films in terms of the resistivity and adhesion. The relevance and limitations of each analytical technique for the examination of thick-film conductors are emphasized
Strain sensitivity in film and cermet resistors: measured and physical quantities
No full textThe strain coefficient of resistivity of resistors deposited on a substrate is analysed, and an expression for its correlation to the measurable longitudinal and transverse gauge factors is given for isotropic (metal, amorphous semiconductor and cermet) resistors. The use of this expression for the evaluation of other physical quantities is exemplified by the calculation of the temperature coefficients of resistivity for resistors on substrates of different thermal expansivity
Reverse photolitographic technique for thicl-film circuits
No full textThe paper deals with reverse photolitographic technique, applied for the first time for the processing of thick-film components on alumina substrates. The SEm phographs of the delineated patterns have revealed excellent edge line definition which is always saw-tooth shaped in the conventional process. various VLSI applicationpotentials have also been pointed out
The state of the art in thick-film sensors
No full textThe speed of evolution of thick-film tchnology as an advanced technique for silid state sensors is illustrated. Recent innovations are mentioned with regard to modern techniques for the design, realization and test of hybrid circuits for signal processing, use of new materials both for substrates and transducing elements, new concept designs and processing techniques. Current research activies and programmes, which promise new interesting materials for, and emerging applications of, thick-film sensors, are described. However, several problems remain unsolved; some topics which should improve our understanting and performance of thick-film sensors are mentioned
SEM-EDAX analysis of interaction of photoresist with thick-films
No full textThe SEM-EDAX anslysis of the interaction of shypley's positive photoresist AZ-1350J with thick-film pastes DP9596 and DP1441 is reported. The interaction is found to make the resistor surface smoother and conductor surface denser than those of processed conventionally. The golf from DP 9596 (pt-Au) paste is also observed to pass through the photoresist during firing and settle underneath on alumina substrate in tje form of 0.5 mircometers sizd grains. The interaction is found useful for fabricating microlines and cantilevered structures for sensor developmet
Technique for lifting off thick film printed on alumina
No full textA technique for lifting off thick film DP 9596 print fired on alumina substrate is reported. The positive phoresist is used as a relif mask. Various applications of the technique are also pointed out
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