DETERMINATION OF INTERFACE ROUGHNESS BY USING A SPECTROSCOPIC TOTAL-INTEGRATED-SCATTER INSTRUMENT

A spectroscopic total-integrated-scatter instrument has been construct ed. It uses a Coblentz sphere for the collection of the scattered ligh t and a lamp with a monochromator as a light source. It can be used to measure diffuse reflectance as well as transmittance. The instrument has been used to measure diffuse reflectance of thermally and chemical -vapor-deposition oxidized silicon wafers. Comparisons are made with m easurements by using a spectrophotometer with an integrating sphere. T he data have been interpreted with a parameterized model for light sca ttering from a double layer, to obtain rms surface roughness values fo r the two interfaces of the oxide film.