Application of Infrared Spectra of UV Irradiated Acetylacetone Photoproducts to a Novel Actinometer for UV Laser Nanoprocessing

Abstract

Chemical actinometer for UV laser nanoprocessing has been developed using infrared spectroscopy for the photoproduct of UV irradiated acetylacetone. Sample was hexafluoroacetylacetone, HFA, in which the H atoms of two methyl groups of acetylacetone are replaced by F atoms. It was irradiated by a KrF excimer laser with the oscillation wavelength of 248 nm during 100 seconds and the photoproducts were analyzed by transmittance measurement of FT-IR in the spectral region between 3500 cm^-1 and 1300 cm^-1. One of the photoproducts was CO and its formation efficiency was estimated to be approximately 0.6. The photodissociation reaction of HFA is expected to be useful for the actinometer by IR spectroscopy of the photoproduct.