Surface morphology and residual stress of electroplated and electroless copper deposits

Abstract

In thls bark, surface n~orphology characterisation and residual stress measurements have been carried out on electroplated and elecnoless copper deposits The surfaces of the solution and substrate sides of the freestandmg electroplated copper deposits from stainless steel substrates ha\e been studied at as-deposited cond~t~on and after heat tieatment at 140°C for 1 hour Electroless copper depos~ts with different substrates (copper cladded and larmnated polymers. and screenprinted dielectr~c substrate) ha~e also been studied at the tuo cond~tions The surface morphology has been characterised using optical rmcroscopy and scanning electron niicroscopy (SEhl) Residual suiface stress measurements \>ere perfom~ed using the techn~que of X-raq d~ffraction method The morphology of the as-deposited electroplated copper film on the substrate side includes numerous small roids scattering across the surface of the deposit. nith relatively large cracks at some portlons ho ~oids uere obsened in the deposit on the solution side These features lemained after heat treatment In the electroless copper deposits, the granular partxles de~elopsd on the heat-treated deposit nere the most intensne. folloned by the deposits on the larmnated and on the copper cladded substrates. iespectn ely ho significant amount of residual surface stress has been detscted in the as-deposited slectroless copper deposlts