Noise properties of thick-film resistors in extended temperature range

Results of thorough experimental studies on electrical properties of thick-film resistors (TFRs) have been overviewed and summarized. Experiments covered resistance and noise measurements in wide temperature range. Low-frequency noise spectroscopy has been used for the investigations of fluctuating phenomena. Sample resistors were prepared of various combinations of commercial and laboratory-made conducting and resistive pastes and printed on alumina substrates. Resistive pastes were made of materials: (i) Pb-containing RuO2and Bi2Ru2O7-based, (ii) Pb/Cd-free RuO2-, CaRuO3-, and RuO2/CaRuO3based. Conducting pastes included Ag, Ag–Pd and Ag–AgPt–Pd, Au, PtAu as a main ingredients. Electrical properties of various TFRs made of different materials were compared. Cross-correlation technique of noise spectra measurements in conjunction with the multiterminal configuration of TFRs was used in investigations of noise vs. resistor volume, resulting in extraction of noise components originated in different parts of the resistor. Furthermore, noise of the resistor was split up into bulk and interface noise. Resistance noise, observed in all studied TFRs, has been found to consist of background 1/f noise and Lorentzian noise induced by thermally activated noise sources (TANSs). Properties of TANSs have been described and their relation to TFRs performance parameters have been pointed out. Noise properties of various Pb-containing and Pb/Cd-free resistive materials have been compared with the use of bulk noise intensity parameter, Cbulk. Conclusions concerning compatibility of resistive and conductive pastes have been formulated. They might be useful in further improvement of materials systems for thick-film technology in order to fabricate low-noise and stable passives. 2011 Elsevier Ltd. All rights reserved.