IN-SITU ELLIPSOMETRIC OBSERVATIONS OF THE GROWTH OF SILICON THIN-FILMS FROM FLUORINATED PRECURSORS, SIFNHM (N+M-LESS-THAN-OR-EQUAL-TO-3)

The growth of silicon thin films fabricated from fluorinated precursors SiF(n)H(m) (m+n less-than-or-equal-to 3), was investigated for the first time by in situ ellipsometric observation. Specific dependencies were recognized of the ellipsometric trajectories in the (psi, DELTA) plane on chemical species used as the precursors. Under certain film preparation condition wherein the structures formed depend greatly on parameters such as the substrate temperature and the substrate material, the film structure was altered from amorphous to polycrystalline or epitaxial. The ordering of the structure was gradually improved with an increase in the thickness. Under the other condition, mu-crystalline films with columnar texture were fabricated independently of substrate temperature or material.