Femtosecond-laser-induced delamination and blister formation in thermal oxide films on silicon (100)

Silicon (100) substrates with thermal oxide films of varying thickness were irradiated with single and multiple 150 fs laser pulses at normal and non-normal incidences. A range of laser fluence was found in which a blister or domelike feature was produced where the oxide film was delaminated from the substrate. At normal and non-normal incidences blister features were observed for samples with 54, 147, and 1200 nm of thermal oxide. The blister features were analyzed with optical and atomic force microscopy. In addition, the time frame for blister growth was obtained using pump-probe imaging techniques.