We have manufactured and characterized low thermal budget gate oxides on Si/Si1-xGex/Si substrates. We study the status of the SiGe buried layers after the thermal budget for gate oxide formation with high-resolution X-ray diffraction analysis and the electrical measurements. We observe this type of characterization to be a candidate for future fast turnaround methodology for SiGe buried layer analysis under post-gate oxide conditions. (C) 2002 Elsevier Science Ltd. All rights reserved.