Inventors:
Daxesh K. Patel - Hatfield PA
Jay D. Baker - Detroit MI
Assignee:
Ford Motor Company - Dearborn MI
International Classification:
C23C 2600
Abstract:
A method is provided for forming a thick-film circuit having at least one thick-film resistor element upon a substrate and laser scribing the substrate to remove the circuit from the remaining portion of the substrate. A thick-film circuit comprising conductor lines and at least one resistor element is first printed upon a substrate. Thereafter, the resistor element may be laser trimmed to increase the resistance value thereof. After laser trimming, a protective material such as ethyl cellulose is coated onto the outer surface of the resistor element to protect it from hot-slag ceramic material generated during a laser scribing operation. The substrate is then topside laser scribed to separate the thick-film circuit from the remaining portion of the substrate. Following laser scribing, the protective material is removed by washing the resistor element with a solvent.