Integral plated resistor and method for the manufacture of printed circuit boards comprising the same
OwnerPeter Kukanskis, Steven Castaldiinventors
Life of this patent
Estimating the term…
Abstract
An integral plated resistor having an improved range of resistance is produced by uniformly dispersing an effective amount of various particles in an electroless nickel phosphorus plating composition so that the particles are codeposited with the electroless nickel phosphorus plating composition. Preferred particles include, polytetrafluoroethylene, silicon carbide, tungsten carbide, and other particles that fully sinter at a temperature of less than about 170° C. The improved nickel phosphorus plated resistors of the invention demonstrate increased stability during manufacturing press cycles and a greater range of resistance values than have previously been achieved.
Claims9
A method of manufacturing a printed circuit board with integral plated resistors, comprising the steps of:
- a) forming a circuit pattern on a surface of a metal clad laminate, which laminate comprises a polymer-based core, and leaving openings in said circuit pattern onto which a resistive material can be plated;
- b) coating said circuit with a resist and exposing said circuit so that the openings in the desired pattern and a portion of the metal cladding are exposed;
- c) conditioning and selectively activating the exposed areas of the laminate to accept plating thereon;
- d) stripping the resist;
- and
- e) plating the activated area with said resistive material to create an integral plated resistor,
- wherein the resistive material comprises an electroless nickel-phosphorus plated composition and about 10 to about 20% by weight of particles, said particles being selected from the group consisting of polytetrafluoroethylene, silicon carbide, tungsten carbide, particles that fully sinter below 170° C., and combinations of the foregoing uniformly dispersed therein, and wherein the electroless nickel-phosphorous plated composition comprises at least 9% by weight phosphorous.
Dependencies are inferred from the claim text.