Conduction Mechanisms in Thick Film Microcircuits
Abstract
This report describes a wide range of experimental studies which led to the development of models relating the sheet resistance and temperature coefficient of resistance (TCR) of thick film resistors to physical properties of the ingredient materials. The system studied was ruthenium dioxide conductive (RuO2), lead-borosilicate glass (63% PbO-25% B2O3-12% SiO2) and alumina substrate (96% Al2O3-AlSiMag 614). The pertinent physical properties of these ingredient materials were measured when these data were not available from previous work. The resistor properties and materials properties were related through studies of microstructure development. The processes involved in microstructure development include: glass sintering, glass spreading, microrearrangement, glass densification, conductive sintering, and conductive ripening. The kinetics of these processes depend on surface tension of the glass, viscosity of the glass, density of the glass, particle size of the glass, particle size of the conductive, surface energy of the conductive, interfacial energy between the conductive and the glass, and solubility of the conductive in the glass. The sheet resistance and TCR depend on all these materials properties in addition to resistivity and TCR of the conductive. A model is developed which reproduces the experimental blending curve over six orders of magnitude in sheet resistance, and can account for any observed TCR in thick film resistors. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Dec 01, 1975
- Accession Number
- ADA024825
Entities
People
- R. W. Vest
Organizations
- Purdue Research Foundation