Depositing copper patterns on Teflon

Abstract

Printed circuit boards composed of patterned cooper features on poly(tetrafluorethylene), better known by the E.I. du Pont de Nemours and Company trade name Teflon, are currently used for high-frequency applications. The choice of these materials is based on the high conductivity of copper and the facts that Teflon has One of the lowest reported dielectric constants ({approximately}2.0). Low dissipation factors. High thermal stability. High chemical resistance. This paper reports that the high conductivity of copper, coupled with the low dielectric constant of Teflon, allows high-frequency operation and/or extensive miniaturization. However, one of Teflon's most important properties is chemical and physical inertness. While this property is extremely attractive in numerous applications involving hostile environments, it presents major problems in metallization for electronic applications. To address this condition, researchers at Sandia National Laboratories and the University of New Mexico have developed a three-step, additive method for the patterned deposition of copper on Teflon. Still, while the example of deposition work examined in this article is recent, it is nonetheless supported by considerable prior work on the patterned etching of Teflon and copper chemical vapor deposition (CVD).