An ion beam deposition system has been used to deposit thin films of carbon with many diamondlike properties [S. Aisenberg and R. Chabot, J. Appl. Phys. 42, 2953 (1971)] which were subsequently confirmed by others [E.G. Spencer, P. H. Schmidt, P. C. Joy, and F. J. Sansalone, Appl. Phys. Lett. 29, 118 (1976)]. Included among properties are transparency, chemical inertness, strong substrate adhesion, high index of refraction, low optical loss over a wide spectra range (visible up to 40 mμ), and with resistivities ranging from 109 to 1016 Ω cm. The films have been observed by SEM to be much smoother than the substrates. An explanation of this effect is that the free surface energy of the mobile surface atoms is much higher (over an order of magnitude) than of liquid metals. The higher free surface energy (erg/cm2 or surface tension in dyne/cm) of the nonequilibrium surface atoms provides a stronger driving force towards minimum surface energy and minimum area and very smooth surface. One interesting application of this diamondlike carbon deposition process is hermetic barrier coatings on optical fibers (to reduce loss of strength with time normally due to water vapor and stress corrosion) and on suboptical memory disks, to give longer archive lifetimes.