Lifetime and material characteristics of multicrystalline silicon measured with high spatial resolution

Modulated free-carrier absorption is used as a new lifetime mapping technique. Differences to other techniques are explained and examples for lifetime maps are given. The method is used to compare lifetime maps with other material characteristics, as crystal structure and interstitial oxygen concentration. For this investigation highly resolved O/sub i/ maps have been measured with a fourier-transform spectrometer, extended with an infrared microscope. The evolution of the interstitial oxygen concentration after different heat treatments was measured using the fourier- transform spectrometer and compared with the minority carrier lifetime, in order to investigate the electrical activity of interstitial and precipitated oxygen.