SEM/EDS study of metal-assisted oxide desorption

Strongly-enhanced desorption of a thick (100 nm) silicon oxide layer by the pre-sputtering of a thin germanium surface film was observed under high-temperature vacuum annealing conditions. High-resolution SEM imaging reveals that germanium nanoislands are first formed on the sample surface, and that these then act as nucleation centres for the formation of voids in the oxide, leading to a rapid desorption of the silicon oxide layer. EDS analysis of the silicon surface after oxide decomposition shows that the introduced germanium impurities are fully consumed in this desorption process.