Published online by Cambridge University Press: 31 January 2011
An alternative bottom-up Cu electro-less deposition (ELD) method without other catalyst material activation tested on blanket wafers, is the focus of this paper. The process consists in reducing the Cu ions via standard reducing agents, such as dimethylamine borane (DMAB). A wide range of experimental conditions such as pH, temperature, Cu ion concentration and time are investigated and the Cu layer nucleation and growth mechanism is evaluated on clean SiO2 and after functionalization with 3-aminopropyltrimethoxysilane (APTS) self-assembled monolayer (SAM) used as copper diffusion barrier. The barrier properties of the APTS layer after Cu ELD are also assessed by copper resistivity measurements and visual inspections as a function of the annealing temperature.