Vapor deposited thin film circuits on ceramic substrates
Abstract
Ceramic substrates from different manufacturers show considerable differences in those properties that make them suitable for the production of thin-film circuits. A sufficiently long pre-aging period improves the stability of NiCr resistors evaporated onto ceramic substrates: 0.3 % change of resistivity after 1000 hrs at 175 C can be obtained. Experiments to minimize the temperature coefficient of resistivity (TCR) resulted in layers having TCR values in range of plus or minus 25 ppm/C; however, a disadvantage of optimum TCR values is reduced resistor stability. A high yield of resistors having tolerances within plus or minus 5% can be obtained only on high quality substrates and by using an improved geometry during evaporation. The optimum geometry was evaluated.
- Publication:
-
Final Report Rohde and Schwartz
- Pub Date:
- July 1976
- Bibcode:
- 1976rsmg.rept.....S
- Keywords:
-
- Ceramics;
- Integrated Circuits;
- Resistors;
- Thin Films;
- Vapor Deposition;
- Chromium;
- Evaporation;
- Nickel Compounds;
- Substrates;
- Temperature Effects;
- Electronics and Electrical Engineering