AVS 45th International Symposium
    Electronic Materials and Processing Division Thursday Sessions
       Session EM-ThM

Paper EM-ThM9
Field Emission Studies of BN Overlayers on Various Substrates

Thursday, November 5, 1998, 11:00 am, Room 316

Session: Compound Semiconductor Surface Chemistry
Presenter: N. Badi, University of Houston
Authors: N. Badi, University of Houston
A. Tempez, University of Houston
D. Starikov, University of Houston
A. Bensaoula, University of Houston
V.P. Ageev, General Physics Institute, Russia
S.V. Garnov, General Physics Institute, Russia
M.V. Ugarov, General Physics Institute, Russia
S.M. Klimentov, General Physics Institute, Russia
E. Loubnin, General Physics Institute, Russia
V.N. Tokarev, General Physics Institute, Russia
K.L. Waters, Ionwerks
A. Shultz, Ionwerks
Correspondent: Click to Email
We have studied electron field emission from BN films deposited on various substrates (flat and tip shaped) by End Hall ion source and electron cyclotron resonance plasma source-assisted physical vapor deposition. The chemical bonding states of B, C, N and the valence band structures were investigated by x-ray photoelectron spectroscopy XPS. Post-growth annealing, thermal processing and surface laser modification effects on the field emission properties were investigated. Thin carbon doped BN films exhibited a turn-on voltage as low as 30 V and a maximum current density of 1A/cm@super 2@. The ield emission nature was verified using Fowler-Nordheim plot studies. A significant difference between the initial I (E)-behavior and that measured during subsequent cycles, with a noticeable stepwise jump of the emission current by orders of magnitude, was observed. Similarly, features in the peak current variation with applied voltage were measured and are probably due to a resonance tunneling emission effect. To that end, the valence band distribution of both the acceptor and donor's energy levels in these BN thin films were investigated under a variety of excitations. In addition, the field emission and conductivity properties of the BN surfaces have been performed using scanning tunneling emission microscopy (STFEM). The total spatial resolution of this technique was as high as a few nm. The experiments were conducted in the emission mode under negative and positive bias. The 3-D surface topography mapping and its correlation to the field emission properties were investigated and the results will be presented and discussed. This work was supported by funds from a NASA cooperative agreement #NCC8-127 to SVEC, a Texas Advanced Research Program Grant # 1-1-27764, and a Texas Advanced Technology Program Grant # 1-1-32061. This material is also based upon work supported by the U.S. Civilian Research and Development Foundation under Award No. REI-247