GaSb(001) Surface Reconstructions Measured at the Growth Front by Surface X-ray Diffraction

• Published in: Journal of electronic materials Vol. 37; no. 12; pp. 1793 - 1798
• Main Authors: Tinkham, B.P., Romanyuk, O., Braun, W., Ploog, K.H., Grosse, F., Takahasi, M., Kaizu, T., Mizuki, J.
• Format: Journal Article
• Language: English
• Published: Boston Springer US 01.12.2008; Springer Nature B.V
• Subjects: Characterization and Evaluation of Materials; Chemistry and Materials Science; Diffraction; Electronics and Microelectronics; Instrumentation; Materials Science; Molecular beam epitaxy; Optical and Electronic Materials; Solid State Physics; Surface roughness; X-rays; molecular beam epitaxy (MBE); x-ray diffraction; GaSb surface
• ISSN: 0361-5235; 1543-186X
• DOI: 10.1007/s11664-008-0557-6

Surface x-ray diffraction was employed, in situ , to measure the GaSb(001)-(1 × 5) and (1 × 3) surface phases under technologically relevant growth conditions. We measured a large set of fractional-order in-plane diffraction peaks arising from the superstructure of the surface reconstruction. From the data we calculated two-dimensional (2D) Patterson functions, the peaks of which represent inter-atomic distances weighted by the number of electrons in the individual atoms. For the (1 × 3) phase we obtained good agreement between our data and the β (4 × 3) model proposed in recent experimental and theoretical work. Our measurements on the Sb-rich (1× 5) phase provide evidence that the structure under growth conditions is, in fact, different from that of the models previously suggested on the basis of scanning tunneling microscopy (STM). We discuss reasons for this discrepancy as well as the identified structural elements for these reconstructions, which include surface relaxations and subsurface rearrangement.