Optimization of InP microchannel epitaxy on Si substrate achieved by addition of upper source

In InP microchannel epitaxy (MCE) by liquid-phase epitaxy (LPE), a Sn + In solution is used to grow a layer with n-type doping. The high solubility of P in Sn gives high interface supersaturation (sigma(i)), which results in a low MCE width to thickness ratio (W/T ratio). To decrease sigma(i) and to obtain a wide MCE layer, an InP upper source was employed. By changing the size of the upper source, the growth condition was optimized and wide disl ocation-free n-type TnP MCE layers, whose widths were as large as 250 mu m, have been obtained on Si substrates. An InP-based MQW structure was grown on an MCE layer on an Si substrate by MOCVD. Photoluminescence measurements of the structure revealed that the optical quality was as excellent as tha t of the structures grown directly on InP substrates. (C) 2000 Elsevier Sci ence B.V. All rights reserved.