Intrinsic stress, island coalescence, and surface roughness during the growth of polycrystalline films

Sheldon, B. W. and Lau, K. H. A. and Rajamani, A. (2001) Intrinsic stress, island coalescence, and surface roughness during the growth of polycrystalline films. Journal of Applied Physics, 90. pp. 5097-5103. ISSN 0021-8979

[img] PDF
1.1412577.pdf
Final Published Version

Download (350kB)

    Abstract

    During film growth by a variety of techniques, intrinsic tensile stresses can be created by the coalescence of neighboring islands. Experimental results with diamond films produced by chemical vapor deposition are compared with a relatively simple model to demonstrate that a realistic interpretation of these coalescence stresses must account for effects that are associated with surface roughness. First, the interpretation of curvature measurements during the early stages of film growth must account for this surface roughness. Also, the experiments show that tensile stresses are induced by grain boundary formation during continuing growth after the initial island coalescence event. This understanding differs from the traditional interpretation that continuing intrinsic stress is produced by "templated" growth onto an already strained crystalline lattice. A kinetic model of stress evolution during postcoalescence growth is also presented. (C) 2001 American Institute of Physics.