Synchrotron X-ray topography study of defects in epitaxial GaAs on high-quality Ge

✍ Scribed by A. Lankinen; L. Knuuttila; T. Tuomi; P. Kostamo; A. Säynätjoki; J. Riikonen; H. Lipsanen; P.J. McNally; X. Lu; H. Sipilä; S. Vaijärvi; D. Lumb

• Publisher: Elsevier Science
• Year: 2006
• Tongue: English
• Weight: 237 KB
• Volume: 563
• Category: Article
• ISSN: 0168-9002
• DOI: 10.1016/j.nima.2006.01.066

✦ Synopsis

Crystal defects of GaAs thin films deposited by metalorganic vapour phase epitaxy on high-quality Ge substrates are studied by synchrotron X-ray topography. The GaAs thin films were measured to have % 500 dislocations cm À2 , which is a similar number to what plain Ge substrates show. The dislocation densities measured are also smaller than, for instance, those of high-quality vapour pressure controlled Czochralski grown GaAs wafers, which typically have dislocation densities of % 1500 cm À2 . The GaAs films grown on both sides of two-sided substrates display very good crystal quality throughout the sample.