Abstracts Category : Other

The effects of ion-assisted deposition on the surfaceroughness of evaporated thin films

by Michael S Jin

The effects of ion-assisted deposition (IAD) on thesurface roughness of electron-beam evaporated films were studied.The experimental study was conducted with an 8 cm Kaufman type ionsource in a 28 inch coating chamber. The investigated filmmaterials were TaO, ZrO, and TiO. </br>In orderto investigate the effects of the IAD process on the surfacequality of the films, the surface statistics of the resulting filmsamples were examined. The rms roughness of the film surfaces wasassessed with a Talystep mechanical profilometer and a totalintegrated scattering (TIS) apparatus. The profilometric data fromthe Talystep measurements were used to calculate the characteristicfunctions of the film surfaces. The height distribution, theautocovariance, and the power spectral density of the surfaceprofile functions were evaluated numerically. The thin filmnucleation and growth phenomena was reviewed in order to identifythe physical interactions between the ions and the depositingmolecules which lead to the changes in the physical and opticalproperties of the IAD processed films. </br> Theion-assisted film samples were prepared at ion energies and arrivalrates which led to the observed changes in other IAD study reports.The changes induced in the films were initially verified with awideband optical transmission monitor which gave information on thetransmission characteristics and the environmental stability of thedeposited films. </br>The changes in themicrostructure of the film samples were examined by transmissionelectron microscopy and by x-ray and electron diffraction methods. </br>The results of the analyses were compared todetermine the effects of each set of IAD parameters on the overallquality of the resulting films.