Thickness-deconvolved structural properties of thermally grown silicon dioxide films

We have studied structural and optical properties of thermally grown silico n dioxide films. These properties were examined by incrementally etching ba ck the oxide films and performing infrared reflection absorption spectrosco py measurement at each thickness. We have divided the oxide into incrementa l layers and calculated the dielectric function of each of the layers. This study shows that the incremental layer, whose structure differs from that of bulk oxide, with thickness below 1 nm exists at the silicon and silicon dioxide interface. In addition, farther from the interface, the transverse optical mode frequency shifts slightly in wave number to a higher value. (C ) 1999 American Institute of Physics. [S0021-8979(99)00118-8].