direct contact to shallow junctions in integrated circuits and interconnection between these contacts is achievable by utilizing a specific aluminum cvd process . in this process the aluminum is deposited utilizing a triisobutyl aluminum precursor onto a substrate having a nucleation layer , e . g . a titanium nitride layer . by appropriate choice of this nucleation layer to control the nucleation of the depositing aluminum , suitable contact is made while avoiding void defects present in the absence of such layer .