The effects of substrate composition on thick film circuit reliability
Abstract
During this quarter studies of the rate of the dissolution of 96% Al2O3 substrates (AlSiMag 614) in the model glass (63%PbO, 25% B2O3, 12% SiO2) were conducted as a function of temperature from 750 to 1000 C. The rate limiting steps were found to be phase boundary reaction rate control at short times and diffusion through a boundary layer under natural convection at longer times. The rate equations developed from the experimental data allow the prediction of the total quantity of substrate dissolved in the resistor glass under any processing conditions. Standard processing (800 C, 10 minutes) for the model system will result in a fired resistor volume containing 17% of ingredients derived from the substrate. Studies of the distribution of substrate ingredients throughout the resistor glass and the influence of substrate constituents dissolved in the glass on electrical properties were initiated during this quarter. Certain information concerning characterization of the substrates was obtained from the supplier and plans for obtaining the additional characterization data needed were formulated.
- Publication:
-
Quarterly Technical Report
- Pub Date:
- August 1976
- Bibcode:
- 1976puwl.reptS....V
- Keywords:
-
- Circuits;
- Substrates;
- Thick Films;
- Electrical Properties;
- Glass;
- Microstructure;
- Reaction Kinetics;
- Electronics and Electrical Engineering