Patent ID: 7617591
Filing Date: 2009-11-17
Classification: H01C,H05K,Y10T

Abstract:
1. A method for fabricating embedded thin film resistors of a printed circuit board comprising the steps of: (a) forming conductive wires with resistor wells according to layout requirement of circuitry on a substrate made of an insulating polymer by a method selected from the group consisting of subtractive, additive, and semi-additive, said resistor wells being formed on top of said substrate and having said conductive wires as side walls and said substrate as bottom; (b) coating an activated layer based on locations, dimensions, and contact points of resistors required by said printed circuit board on said contact points and said side walls of said conductive wires with said activated layer covering said bottom of said resistor wells; and (c) immersing said printed circuit board in an electroless plating solution so that a resistor layer having a first volume resistivity is plated on said activated layer until said resistor layer is deposited to a first thickness.