| On the base of the development of thick film pastes technology, Ru-based thick film resistor pastes have been studied due to select conductive phase and inorganic binder. State-of-the-art techniques such as rolling, screen printing and sintering were used for sample preparation. Effects of ingredients, printing parameters and sintering parameters, microstructure on the properties of thick film resistor (TRF) have been analyzed with XRD, SEM, DSC and electrical tests.Bismuth ruthenate and silver were selected as conductor phases and the mixture of calcium oxide-alumina-silicon dioxide (CaO-Al2O3-SiO2) glass and lead oxide-boron oxide-silicon dioxide (PbO-B2O3-SiO2) glass was selected as inorganic binder phases. It was found that, with the increasing of volume fraction of silver and conductor phase, sheet resistivities descend and there are critical thresholds.The average partical size of bismuth ruthenate and PbO-B2O3-SiO2 glass was researched. The smaller bismuth ruthenate partical is, sheet resistivity is lower and temperature coefficient of resistance (TCR) is more positive and the refiring change ratio is nearer to zero. The limit size of bismuth ruthenate partical is 0.56μm. PbO-B2O3-SiO2 glass partical has an extremum which is 1.51μm. At this point, sheet resistivity is minimal. Meanwhile, TCR and the refiring change ratio is near to zero.Compound inorganic binder was put forward firstly. The controllable regulation on refiring change ratio can be acquired by linear principle. When the volume ratio is 1:1, the best sintering temperature is 865℃. PbO-B2O3-SiO2 glass reacts with bismuth ruthenate and lead ruthenate is produced as transition layer. The transition layer can make the interface gradually change and the properties of resistors are improved at the same time. Based on the study above, the way to get series of pastes was developed. Firstly, desired sheet resistivity and TCR can be achieved by the changement of volume fraction of silver and conductor phases. Secondly, appropriate refiring change ratio is gained by designing compound inorganic binder.Effects of additional inorganic constituents on properties of TRF were studied. It shows that CuO and MnO2 make sheet resistivity lower. Other semiconducting oxides such as Nb-2O5,Bi2O3 and V2O5 also broaden sheet resistivity range and make pastes cost lower. The properties of the Bi2Ru2O7/Ag based resistor pastes developed in this paper are as followed: (1) the resistivity ranges from 30Ω/□to 1MΩ/□; (2) the TCR ranges from -100×10-6/oC to 100×10-6/oC; (3) the value of the change rate of resistivity after refiring is lower than 5%.
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