A NOVEL METHOD OF CREATING RESISTORS IN PRINTED WIRING BOARDS
Original Publication Date: 1998-Sep-01
Included in the Prior Art Database: 2002-Jul-16
A method of creating resistors in primed wiring boards was developed. The method consists of creat- ing a suitable size hole in the substrate and filling the aperture with an appropriate resistive ink. The sub- strate may be organic or ceramic and the ink used a common polymer thick film version or a fireable ver- sion depending on the substrate type. Excess ink is removed from the top and bottom surface of the sub- strate by a suitable method such as abrading. It is preferable to remove the polymer thick film inks after the curing step. However, it is preferable to remove the ceramic resistive material prior to firing. Metal ter- minals to the resistor are applied subsequent to the for- mation of the final resistor by any commonly used methods of applying metal in printed wire board con- structions The cross section area of the hole, substrate thickness, and ink resistivity are used to control the final value of the resistor.