Device and method for performing an optical hall test

The device and method for performing an optical Hall test provide means for non-destructive measurement of free carrier concentration or effective mass in semiconductor materials using Faraday rotation spectra. A beam emitted by a Fourier transform infrared (FTIR) spectrometer is transmitted through the sample that is mounted between a polarizer and analyzer and the opposite poles of a magnet before finally being incident on a detector. The ratio of the samples's transmission spectrum with the magnetic field on to that with the magnetic field off is converted, through a suitable mathematical formula, to Faraday rotation. The rotation is, then, plotted versus the square of the wavelength. The slope of the graph at longer wavelengths is directly proportional to the carrier concentration and the effective mass. With one known, the other can be easily determined.