Electroplating of poly(tetrafluoroethylene) using plasma enhanced chemical vapor deposited titanium nitride as an interlayer

Abstract

A low-temperature process for titanium nitride (TiN) deposition by means of an electron cyclotron resonance (ECR) plasma enhanced chemical vapor deposition process was applied to poly(tetrafluoroethylene) (PTFE). Tetrakis(dimethylamido)titanium introduced into the downstream region of a nitrogen ECR plasma was used as a precursor for TiN deposition at 100 °C. The thin TiN films (thickness 15–30 nm) act as interlayers to activate the electroless deposition of copper followed by an electroplating process. Prior to the deposition of the interlayer, the samples were treated on a biased susceptor with argon ions to enhance the adhesion of the TiN interlayer. This metallization procedure avoids the use of toxic and pollutive etching agents and yields adherent copper layers on PTFE. Films were characterized by four-point probe resistivity measurements, atomic force microscopy, and secondary ion mass spectrometry.