Femtosecond laser ablation dynamics of amorphous film of a substituted Cu-phthalocyanine

Femtosecond laser ablation dynamics of an amorphous thin film of a substituted Cu-phthalocyanine was studied using time-resolved absorption spectroscopic and scattering imaging methods. Above the ablation threshold of 45 mJ/cm(2), the etch-depth is about 400 nm and almost constant up to a laser fluence of 300 mJ/cm(2). Transient absorption spectra confirmed that the electronic excitation energy is converted to heat through exciton-exciton annihilation within 100 ps after excitation. The etching profile and ablation threshold are discussed in connection with the heating rate. (C) 2000 Elsevier Science B.V. All rights reserved.