OPTICAL NEAR-FIELD CHARACTERIZATION OF SUBMICRON STRUCTURED SILICON FILMS

Optical near-field microscopy provides a variety of contrast mechanism s with possible nanometre resolution. For the first time we used optic al absorption contrast in order to analyze ion-irradiated silicon film s. A finely focused 17 keV Ne+ beam produces local amorphous areas wit h an enhanced optical extinction coefficient in a crystalline Si matri x. The photon scanning tunnelling microscope, a variant of the optical near-field microscopes, is very suitable to image the damaged areas w ith sufficient spatial resolution. The mechanism of the contrast origi n is discussed.