Hydrogen redistribution and gettering in AlCu/Ti thin films

Abstract

Redistribution and uptake of hydrogen was found to occur during anneals in forming gas (90% N2+10% H2) of thin-film AlCu/Ti/AlCu sandwich layers deposited on a thin layer of SiO2. Annealing at 350 or 400 °C for 30 min caused the Ti-containing layer to getter hydrogen, which came from both the upper and lower interfaces of the SiO2 and from the gas. The uptake kinetics from the gas were surface limited. The hydrogen distribution was influenced by the formation of TiAl3, in which the solubility of hydrogen was found to be negligible. Hydrogen in partly reacted layers was found to be associated with unreacted titanium.