Ivan Ohlídal, Daniel Franta, Jaroslav Hora, Karel Navrátil, Jan Weber, Pavel Janda

Analysis of thin films with slightly rough boundaries

Mikrochimica Acta 15 (1998) 177–180

Technological procedures often produce thin films with rough boundaries as for example, semiconductor films prepared by various chemical methods. If roughness of the boundaries of the films is very small, i.e. if the rms values of the heights of boundary irregularities are equal to several nanometers, it is very difficult to carry out a detailed analysis of the films. Spectroscopic ellipsometry and atomic force microscopy represent two experimental techniques enabling us to determine some important parameters of these films (e.g. thickness) together with the main statistical quantities characterizing slight (nanometric) roughness of their boundaries. In this paper a method will be presented based on a combination of variable angle spectroscopic ellipsometry, spectroscopic reflectometry and atomic force microscopy enabling us to determine the optical parameters and the most significant statistical parameters of the rough boundaries characterizing the slightly rough single layers. Within the method the generalized Rayleigh–Rice theory published elsewhere will be used for interpreting experimental data obtained from both the optical techniques, i.e. variable angle spectroscopic ellipsometry and spectroscopic reflectometry. The method will be illustrated by presenting experimental results achieved by applying the method to slightly rough surfaces of single crystals of GaAs covered by very thin surface layers (i.e. by native oxide layers).

Download PDF (6008 kB)

You can also contact one of the authors: ohlidal@physics.muni.cz, franta@physics.muni.cz

Citing Articles

1. Franta D., Nečas D., Zajíčková L., Buršíková V., Cobet C.,
   Combination of synchrotron ellipsometry and table-top optical measurements for determination of band structure of DLC films,
   Thin Solid Films 519 (2011) 2694-2697

Cited Articles

1. Ohlídal I., Vižďa F., Ohlídal M.,
   Optical analysis by means of spectroscopic reflectometry of single and double layers with correlated randomly rough boundaries,
   Optical Engineering 34 (1995) 1761–1768
2. Navrátil K., Ohlídal I., Lukeš F.,
   The physical structure of the interface between single-crystal GaAs and its oxide film,
   Thin Solid Films 56 (1979) 163–171