Deposition of Aluminum--Copper Alloy on Laminated Polyimide Substrates from a RF Induction Source

摘要

A physical vapor deposition process with a rf induction vapor source has been developed to deposit 11.2- mu m Al--Cu alloy on polyimide laminate substrates. The average thickness uniformity (standard deviation/average thickness) of the deposit acquired by a beta backscatter technique was approximately 1% for these deposits. The Al-0.3 wt % Cu vapor charge results in a Cu content in the deposit of 0.12 wt %. The Cu shows no preferential deposition pattern, as related to the surface of the laminate and its dispersion throughout the deposit. The resistivity of the Al--Cu deposits is 3.0 mu omega -cm and is stable from one deposition run to another. Also, the resistivity was not related to the geometry of the domed substrate. The density of the 11.2- mu m-thick Al--Cu film was within 1% of theoretical, and its adhesion to the polyimide exceeds that required for post-deposition operations and handling. The deposited films exhibited a specular reflectance above 90% with a 632.8 nm wave length source and a grain size of 0.6 mu m throughout the deposit. (ERA citation 04:039331)