Excimer lamp-induced decomposition of platinum acetylacetonate films for electroless copper plating

Photo-induced decomposition of platinum acetylacetonate films using an exci mer VUV source of 172 nm radiation is reported. VUV irradiation of a substr ate coated with platinum acetylacetonate film results in the formation of p latinum, which acts as an activator for copper plating by means of a subseq uent electroless bath process. Selective copper patterns can thus be formed by employing patterned VUV irradiation through a quartz contact mask to di mensions approaching the submicron level. The platinum films formed and the platinum acetylacetonate layers used were characterised using ultraviolet spectrophotometry (UV) and Fourier transform infrared (FTIR) spectrometry. The photo-decomposition of the platinum compounds was found to be a functio n of both the UV dose and chamber pressure during irradiation. The morpholo gy of the copper layers was investigated with a scanning electron microscop e (SEM). (C) 1999 Elsevier Science Ltd. All rights reserved.