Effect of target modification on deposition rates of hexaphenyldisilane bylaser ablation

The effects of target modification on film deposition rates of hexaphenyldi silane (HPDS) due to ablution by a 248-nm KrF excimer laser at different fl uences and repetition rates were studied. When the repetition rate was less than 20 Hz and the laser fluence was below 100 mJ/cm(2), some interlocked cones were generated on the surface of the HPDS targets, which caused the l aser ablative process to grind to a halt after a given number of laser puls es. However, when the repetition rates exceeded 20 Hz, it was possible to p revent the cones from being interlocked, so that the laser ablative process or film deposition process could continue, even though a similar laser flu ence was used. The doping of other Si-based organic materials into HPDS aff ected the critical laser fluences and repetition rates below which the inte rlocked cones were generated. Finally, a general physical model of the targ et modification for laser ablation of Si-based organic materials was sugges ted based on the laser processing parameters. (C) 1999 Elsevier Science B.V . All rights reserved.