Effects of amine fluoride cleaning chemistry on metallic aluminum integrated circuit films - I. Experimental measurements and chemical Modeling

Amine fluoride cleaning chemistry was developed to clean postplasma ash residues from integrated circuits and their metallic interconnects during manufacturing. Thin aluminum films on silicon wafers have been investigated using electrochemical and spectroscopic techniques to illuminate variables of the cleaning process and to determine the molecular mechanism of aluminum surface dissolution and repassivation. A process model was established and a molecular mechanism proposed consisting of a series of sequential chemical reactions describing multisloped open circuit electrochemical potentials. These measurements have led to a detailed understanding of the amine fluoride cleaning process, the aluminum surface cleaning chemistry, and nearly a fivefold reduction in aluminum surface dissolution rate. (C) 2003 The Electrochemical Society.