IN-SITU SEMICONDUCTOR-MATERIALS CHARACTERIZATION BY EMISSION FOURIER-TRANSFORM INFRARED-SPECTROSCOPY

The results of a novel emission fourier transform infrared (E/FT-IR) s pectrometer for in-situ characterization of semiconductor materials is presented. For the experiments, the wafers were heated and the infrar ed emission profiles from the substrates were collected by a standard FT-IR spectrometer. Differences in the emission spectra from different substrates are explained through correlation to the optical propertie s of the corresponding substrates. The in-situ infrared emission spect rum of a lightly doped (10-20 OMEGA.cm) silicon wafer at 200-degrees-C is very similar to its ex-situ transmission spectrum at room temperat ure, although the spectrum is inverted. This similarity makes possible the analysis of E/FT-IR spectra by using existing spectral libraries. Finally, it is shown that the E/FT-IR technique can be used for nonco ntact and noninvasive real-time identification and possibly quantifica tion of impurities during silicon oxidation and for real-time epi-film thickness monitoring during silicon epitaxy.