| Popis: |
Ultra-high purity silicon with high concentrations of interstitial oxygen has been prepared using the float-zone (FZ) technique. In this material, interstitial oxygen concentrations [O]∼ 9×1017 cm-3 have been achieved while maintaining good crystalline structure and a ratio of oxygen to shallow impurities greater than 105. This FZ method provides efficient oxygen “doping” by exposing only the melted zone during boule growth. Results of characterization using IR absorption, photoluminescence spectroscopy, transport and crystal quality measurements are presented. This material is of fundamental importance in the investigation of thermal donors (TDs) in silicon, where contamination from group-III and group-V impurities, and carbon, complicates the role of oxygen in the formation of TDs. |
