Formation and characterization of (553)B In0.15Ga0.85As/GaAs quantum wire structure

Strained In0.15Ga0.85As/GaAs quantum wires (QWRs) are naturally formed on a (553)B-oriented GaAs substrate by molecular beam epitaxy. The QWR structur e with a corrugated upper interface and a flat lower interface is directly confirmed by atomic force microscopy. The average lateral period and step h eight of (553)B QWRs are revealed to be about 25 and 1.6 nm, respectively. Accordingly the density of (553)B QWRs is as high as 4.0x10(5) cm(-1), whic h is several times larger than that of QWR arrays fabricated by the finest lithography. Moreover, the (553)B QWRs are intensively studied by photolumi nescence (PL). In comparison with the reference (100) In0.15Ga0.85As/GaAs q uantum wells, the PL peaks of the (553)B QWRs show slight redshifts and str ong polarization dependence at 12 K, indicating a two-dimensional carrier c onfinement effect due to the corrugated structure. The narrow full width at half maximum of the PL peak at lambda =861 nm is as small as 9.2 meV, whic h indicates the high uniformity and good optical quality of the (553)B QWRs . (C) 2001 American Institute of Physics.