2016 CAP Congress / Congrès de l'ACP 2016

The Effect of Electrolyte Additives on Crystallite Orientation in Galvanic Cu Deposits on ⟨111⟩, ⟨100⟩ and ⟨110⟩ Cu Surfaces

14 Jun 2016, 19:08

2m

SITE Atrium (University of Ottawa)

Poster (Non-Student) / affiche (non-étudiant) Surface Science / Science des surfaces (DSS) DAMOPC Poster Session with beer / Session d'affiches avec bière DPAMPC

Speaker

Ralf Bruening (Mount Allison University)

Description

Copper films for applications in printed circuit boards usually have to be fine-grained to achieve even filling of microvias. When galvanically plating Cu films on roll-annealed Cu substrates, unacceptably large epitaxial crystals were found for certain conditions. Here galvanic Cu films were plated on oriented single-crystal Cu substrates from an additive-free electrolyte and from a commercial electrolyte designed for DC plating. The crystallite distribution in the films was mapped with XRD. For the additive-free bath, the transition to a polycrystalline film occurs more readily on ⟨111⟩ and ⟨100⟩ oriented surfaces, whereas films on ⟨110⟩ substrates are persistently epitaxial. A sequence of recursive twinning steps is the main mechanism for the transition to polycrystalline texture. The bath additives promote fine-grained films and they deliver, for the same plating conditions, remarkably improved results.