Abstract

AbstractEpitaxial growth techniques for ZnSxSe1 − x/ZnSe heterostructures have already achieved a high degree of development. Further improvements strongly require characterisation techniques with high compositional sensitivity and high spatial resolution. Therefore in this work high‐resolution Z‐contrast, which provides compositional information down to the atomic scale, has been used for the first time to characterise ZnSxSe1 − x/ZnSe quantum well structures. The influence of structural defects on Z‐contrast is demonstrated by comparison of scanning transmission electron microscopy (STEM) bright field images and STEM Z‐contrast micrographs of planar defects and dislocations. The compositional abruptness of ZnSxSe1 − x/ZnSe interfaces in MOVPE‐grown quantum well (QW) structures is judged from high‐resolution Z‐contrast micrographs. Electron energy loss spectroscopy (EELS) measurements were performed for the first time in ZnSxSe1 − x/ZnSe QW structures in order to obtain quantitative compositional information with nanometre spatial resolution. From EELS line scans, which monitor the selenium concentration across ZnSe QWs, the obtainable spatial resolution is estimated to be about 1–2 nm. The problems that have prevented quantitative analysis of the selenium concentration up to now are discussed.

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

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.