Epitaxial GeSi strained layer on SIMOX for confinement of threading dislocations

Improvement of the crystalline quality of epitaxial silicon grown on separation by implantation of oxygen (SIMOX) material was investigated by confining the threading dislocations in the silicon top layer with a GeSi strained layer. The standard SIMOX used was produced by implantation of 1.6×10¹⁸ O+/cm² at 160 keV, followed by annealing for 6 h at 1300°C in N₂. Thin Si/GeSi/Si epitaxial structures were grown on the SIMOX and on Si substrates by chemical vapor deposition (CVD). The material was evaluated using a variety of methods, including cross-sectional transmission electron microscopy (XTEM), plane view TEM, and Rutherford backscattering spectroscopy (RBS)/channeling. The GeSi strained layer grown by CVD appears to be high quality, and no misfit dislocations were observed for Si/GeSi/Si structures grown at the same time on bulk silicon. CVD may also be a simple and economical method for growing Si/GeSi/Si structures for device applications such as heterojunction bipolar transistors