Abstract
We present direct evidence for the dependence of critical thickness on growth temperature in a lattice-mismatched epitaxial system. Ge0.5Si0.5/Si strained-layer superlattices have been grown by molecular beam epitaxy on (100) Si substrates at temperatures between 330 and 530 °C. The extent to which lattice mismatch is accommodated by elastic strain has been determined through x-ray diffraction, channeled Rutherford backscattering spectroscopy, and transmission electron microscopy. Lattice mismatch is found to be accommodated purely elastically in a structure grown at 365 °C. Samples grown at higher temperatures are seen to display increasingly high densities of misfit-accommodating dislocations. This growth-temperature dependence may account for apparent inconsistencies in critical thickness data reported in the literature. Our results clearly demonstrate the need to account adequately for the kinetics of defect formation in the prediction of critical thicknesses.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.