AVS 52nd International Symposium
    Plasma Science and Technology Thursday Sessions
       Session PS+TF-ThA

Paper PS+TF-ThA4
PECVD of SiO@sub 2@ Thin Film from Electron-Beam Generated Plasmas

Thursday, November 3, 2005, 3:00 pm, Room 302

Session: Emerging Plasma Applications
Presenter: D. Leonhardt, US Naval Research Laboratory
Authors: D. Leonhardt, US Naval Research Laboratory
S.G. Walton, US Naval Research Laboratory
Correspondent: Click to Email
The deposition of thin films of SiO@sub 2@ is an integral part of flexible displays/electronics, medical implant bio-functionalization, as well as a robust barrier layer ideal for space applications. In all of these applications, the SiO@sub 2@ layer must be uniform and defect free over large areas. Typical plasma-based deposition technologies that are presently used have limitations in both the quality of material being deposited and the uniformity over large (square meter) areas. NRL has used electron beam-generated plasmas to produce a variety of SiO@sub x@ films, with the focus on PECVD processes for temperature sensitive substrates that are scalable to large areas. Mixtures of TEOS or HMDSO with Ar/O@sub 2@ based plasmas were used to grow films in modulated electron beam generated plasmas. The inherent low electron temperature of these plasmas results in low plasma fields and potentials, which in turn provide low energy (< 3 eV) ions to the substrate. The resultant film electrical, optical and chemical properties with respect to gas mixtures, substrate temperature and ion energy will be presented. The low ion energies were critical in producing films with lower defect densities than typical SiO@sub 2@ deposition processes. Using the ion energy as an additional process control ‘knob’ the film composition ranged from stoichiometric SiO@sub 2@ to heavily hydrolyzed. Fluxes to the substrate determined by mass spectrometry measurements will be correlated to these process variables and final film composition. Along with a highly tunable PECVD process, these plasmas offer tremendous scaling and uniformity capabilities that will also be discussed.