Improved uniformity of self-organized In0.53Ga0.47As/In0.52Al0.48As quantum wires grown on (775)B-oriented InP substrate by molecular beam epitaxy

Uniformity of self-organized In0.53Ga0.47As/In0.52Al0.48As quantum wire (QWR) structures grown on (7 7 5)B-oriented InP substrate by molecular beam epitaxy was improved by changing substrate temperature. Both surfaces of In0.53Ga0.47As and In0.52Al0.48As layers grown at 580degreesC on the (7 7 5)B InP substrates were corrugated with different periods and amplitudes, which leads to rather poor uniformity of the (7 7 5)B In0.53Ga0.47As/In0.52Al0.48As QWRs. Surface of an In0.52Al0.48As barrier layer grown at 540degreesC was found to become almost flat. An improved In0.53Ga0.47As/ In0.52Al0.48As QWR structure was fabricated by growing an In0.53Ga0.47As QWR layer at 580degreesC and In0.52Al0.48As barrier layers at 540degreesC. Their full-width at half-maximum (FWHM) values of photoluminescence (PL) observed in the QWRs at 12K became as small as 19meV, which is about 40% smaller than that (31meV) of the previous In0.53Ga0.47As/In0.52Al0.48As QWRs grown at 580degreesC. In addition, more improved uniformity (17 meV at 12 K) was realized by using (In0.53Ga0.47As)(2)(ln(0.52)Al(0.48)As)(2) short period superlattice barriers grown at 540degreesC. These reduced PL-FWHM values are smaller than those of any InGaAs QWRs emitting 1.1-1.35 mum PL reported so far. (C) 2003 Elsevier Science B.V. All rights reserved.