IUVSTA 15th International Vacuum Congress (IVC-15), AVS 48th International Symposium (AVS-48), 11th International Conference on Solid Surfaces (ICSS-11)
    Photonics Materials Topical Conference Thursday Sessions
       Session PH-ThM

Paper PH-ThM9
Two-stage Growth of Patterned Epitaxial Lithium Niobate for Photonic Application

Thursday, November 1, 2001, 11:00 am, Room 120

Session: Photonic Materials: Studies on the Nano Scale
Presenter: L. McCaughan, University of Wisconsin-Madison
Authors: V. Joshkin, University of Wisconsin-Madison
K. Dovidenko, NYS Center for Advanced Thin Film Technoogy
S. Oktyabrsky, NYS Center for Advanced Thin Film Technoogy
D. Saulys, University of Wisconsin-Madison
T.F. Kuech, University of Wisconsin-Madison
L. McCaughan, University of Wisconsin-Madison
Correspondent: Click to Email
LiNbO3 is an ideal material for linear and nonlinear photonic crystals. Potential commercial applications have long been frustrated by the chemical stability of this material. We present a new two-stage growth method for fabricating patterned crystalline LiNbO3 structures for photonic applications. The method is based on physical and chemical properties of amorphous and polycrystal LiNbO3 films grown by high pressure chemical vapor deposition (CVD) from metal alkoxide precursors. In the first stage, the CVD technique is used to deposit amorphous or polycrystalline LiNbO3 films on a crystalline substrate at high deposition rates (~2micron/hr). Patterned structure can now be formed after this first stage using a rapid wet or dry etching of amorphous LiNbO3 (up to 6micron/min depending on etching regimes). In the second stage, a post-growth anneal at high temperature(900°C- 1100°C) converts the film to single crystal LiNbO3. Under the proper annealing conditions, the LiNbO3 bulk self-diffusivity dominates the surface mobility, allowing epitaxial films that maintain the shape of micron-size pattern. These patterned structures are characterized by AES, SEM, HRTEM and DXRD. The effect of substrate on film quality is investigated. Lift-off processing on films grown by two-stage growth technique is demonstrated. Comparison of high vacuum chemical beam epitaxy with high pressure CVD from alkoxides is performed.