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High temperature treatment is the key process in formation of thick resistive films. When these complex structures are in question, materials selection, screen-printing process and high temperature treatment are directly responsible for resistor performances. High temperature treatment regulates the space distribution of conducting and glass phase in the resistor. Strict control of conveyor furnace operation, optimum firing profile, adequate peak temperature and dwelling time spent at the peak temperature determine microstructure of the film. Conduction mechanisms present in the film are directly related to resistor performances. In this paper standard resources for tracking micro and macrostructural changes, resistance and noise index measurements, are used in investigation of effects of thermal processing on properties of thick resistive films.

Temperature sensors are being widely used in various aspects of our lives. One of the most important areas of their application is environmental monitoring. In air velocity measurements resistive temperature detectors are often used. For this reason, as an initial step in development of novel thermo-anemometer that will allow 3D wind speed measurements, a series of Pt resistive film sensors that combine custom made thin-film material and thick-film technology was realized. In this paper these sensors will be presented from design and manufacturing stage to evaluation of sensor performances.

High voltage pulse trimming is the most suitable resistance adjustment method for contemporary thick-film applications that impose stricter requirements on thick-film resistors. In this paper the influence of trimming by energy of high voltage pulses on two thick-film resistor quality indicators that are based on noise index measurements is being examined. Since standard characterization of trimmed thick resistive films is based on the resistance drift with little respect to the nature of observed changes, this paper aims to discuss in more detail how values of both quality indicators, that formally incorporate both transport and low-frequency noise characteristics of the resistor, change with high voltage pulse trimming and whether they can enable evaluation of resistor behavior before and after performed trimming process.

In order to determine possible causes of resistance and noise index changes in thick-film resistors during high- voltage pulse stressing, deterministic model was used. Irreversible micro- and macro-structural changes observed during high- voltage pulse stressing of thick film resistors based on 1, 10 and 100 kOmega/sq compositions were analyzed and performed analysis resulted in determination of primary technological, geometrical and physical parameters responsible for observed changes.

In this paper statistical approach to analysis of mechanically and electrically strained TFRs will be presented using parameters from deterministic model. Noise performances of stained resistors will be explained using redistribution of numbers of contacts and MIM cells as well as adequate contributions of noise due to metallic conduction and noise due to fluctuations in MIM cells to total noise of strained resistor.

In this paper the results from a study of multiple high-voltage pulse stressing effects on resistance and low-frequency noise of thick-film resistors based on resistor composition with sheet resistance of 10kOmega/sq are presented. For the experimental purposes a series of thick-film test resistors with identical geometries were realized and exhibited to two types of tests: multiple series of 10 pulses with amplitude from the 0.5-4.0kV range and multiple series of 10 pulses with 3kV amplitude. Obtained experimental results were analyzed and correlation between resistance and low-frequency noise changes with resistor degradation due to multiple high-voltage pulse stressing is observed. It is shown that low-frequency noise parameters are more sensitive to this kind of resistor stressing than resistance

In this paper the results from a study of simultaneous mechanical and electrical straining effects on performances of conventional thick-film resistors based on resistor composition with sheet resistance of 1kOmega/sq are presented. For experimental purposes a series of thick-film test resistors with different geometries were realized and subjected to simultaneous electrical and mechanical straining using 1.2/50mus pulses in combination with mechanical substrate deflection of 300mum. Obtained experimental results were analyzed and correlation between resistance, noise index and gauge factor changes with resistor degradation due to simultaneous impact of these two types of straining were observed

In this paper a 3D planar random resistor network model as a thick-film resistor model based on percolation theory combined with deterministic model is presented. Thick-film resistors are described as random resistor networks where parameters from deterministic model introduce micro structural characteristics. The percolation site model with double percolation introduces macrostructural characteristics of thick-film resistors into newly developed combined model. The model is illustrated by a computer simulation of thick-film resistor degradation caused by high-voltage pulse stressing. Obtained results are compared with experimental results for thick-film resistors with 10 kOmega/sq and 100 kOmega/sq sheet resistances