Abstract

The buried Si:SiO₂ intcrface, a basic constituent of MOS devices, is one of the most attractive objects for application of second harmonic generation (SHG). The SHG sources are attributed mostly to the broken invasion symmetry of the Si:SiO₂ interface. The main goal of the present work was to study experimentally and theoretically the oxide-thickness dependencc of thee SHG in this system. The following peculiarities of the experiment should be stressed: (i) the oxide thicknesses cover the range between the typical intcrfacc thickness and the SHG wavelength (ii) the sample preparation technique keeps the buried interfacc the same for different oxide thicknesses; (iii) the SHG is measured for the p-in, p-out geomctry at Brewster angle of incidence on the SiO₂air interface to avoid multiple-reflections; (iv) the measurements in air are complemented by those for the samples immerscd in water as a refractive-index- matching liquid.

© 1996 IEEE