Patent ID: 6622374
Filing Date: 2003-09-23
Classification: H01C,H05K,Y10S,Y10T

Abstract:
A method of forming a discrete resistive element of a printed circuit board, comprising the steps of:a) adhering a resistor foil to a dielectric substrate of the printed circuit board, said resistor foil comprised of: a copper layer having a first side and a second side; a tiecoat metal layer having a thickness of between 5 Ã¥ and 70  formed on said first side of said copper layer. a first layer of a first resistor metal formed directly on said tiecoat metal layer; and a second layer of a second resistor metal formed on said first layer of said first resistor metal, said first resistor metal having a resistance different from said second resistor metal, said resistor foil adhered to said substrate with said second layer of said second resistor metal facing said dielectric substrate; b) forming a circuit trace line of the printed circuit board on a surface of said dielectric substrate by etching away unwanted areas of said resistor foil leaving a section of said resistive foil consisting solely of at least one of (a1) said first layer of said first resistor metal and (b1) said second layer of said second resistor metal, thereby forming the discrete resistive element of the printed circuit board.