Optical determination of oxygen outdiffusion in epitaxial silicon grown on n-type Czochralski substrates

Oxygen solid-state outdiffusion from the substrate to the epitaxial layer was investigated by using micro-Fourier transform infrared measurements in a transversal wafer cross-section configuration. Interstitial oxygen concentration, obtained by analyzing the 1107 cm−1absorption band, indicated that an oxygen content, clearly detectable by the infrared technique, is present in the epitaxial layer near the interface. To our knowledge this is the first evidence of oxygen outdiffusion from the substrate into the epitaxial layer.