Size distributions of Ge islands on Si(100) were monitored for coverages of between 3.5 and 14 monolayers and growth temperatures ranging from 450 to 600C. The features of these distributions were correlated with characteristic island morphologies. The mean dome cluster size increased, and the onset of island dislocation was delayed, as the growth temperature was increased. At 600C, very large hut clusters were formed. This behavior was attributed to strain-assisted alloying of the Ge clusters. Energy-dispersive X-ray analysis confirmed the diffusion of Si into the Ge clusters at 600C. An atomistic elastic model supported the interpretation that alloying was driven by strain-energy enhancement near to the island perimeters.

Strain-Driven Alloying in Ge/Si(100) Coherent Islands S.A.Chaparro, J.Drucker, Y.Zhang, D.Chandrasekhar, M.R.McCartney, D.J.Smith: Physical Review Letters, 1999, 83[6], 1199-202