Infrared analysis of the precipitated oxide phase in silicon and germanium

Oxygen-doped germanium samples have been subjected to a prolonged precipitation treatment in the 560–620 °C temperature range. Broad infrared absorption bands with maxima at 865 and 884 cm−1 which develop proportionally with the loss of interstitial oxygen are observed and are attributed to germanium oxide precipitates. Secondary peaks appear at 675 and 958 cm−1. The broad absorption bands are analyzed using a procedure which was previously applied to SiOx precipitates in silicon. Similarly as in silicon, the absorption in germanium may be fitted assuming the presence of polyhedral and platelet GeOx precipitates, with relative occurrence depending on the details of the thermal treatment.