Growth of high-quality InSb films on Si(111) substrates without buffer layers

Molecular beam epitaxial growth of InSb on Si(1 1 1)7 x 7 surface is perfor med in the temperature range, 170-400 degreesC. Epitaxial growth is achieve d by suitably adjusting the growth rate, In/Sb flux ratio and substrate tem perature. For growth temperatures up to 300 degreesC surface morphology and the epitaxial quality of the film improve with temperature, whereas above 300 degreesC, an increase in growth temperature deteriorates the epitaxial growth. Hall measurements reveals that the electron mobility of the film in creases with growth temperature and for the film grown at 300 degreesC it i s about 2200 cm(2)V(-1)s(-1) at RT. Significant improvement in the electric al properties of the film is achieved using a two-step growth procedure, co nsists of 300 Angstrom thick interface layer growth at 300 degreesC followe d by growth at 400 degreesC. The electron mobility of a 1.8 mum thick two-s tep grown film at RT is 23 000cm(2)V(-1) s(-1). Surface morphology, crystal quality and electrical properties of the grown films are discussed with re spect to growth parameters. (C) 2001 Elsevier Science B.V. All rights reser ved.