Features of the Initial Stage of GaN Growth on Si(111) Substrates by Nitrogen-Plasma-Assisted Molecular-Beam Epitaxy

The results of investigations of the effect of the initial conditions (nitridation of the Si(111) substrate, the GaN growth temperature, and the stoichiometry of GaN growth) on the growth kinetics and the GaN/Si(111)-layer polarity under nitrogen-plasma-assisted molecular-beam epitaxy are presented. It is experimentally established that the optimal initial condition for GaN epitaxy on Si(111) substrates is high-temperature nitridation of the Si(111) substrate carried out immediately before GaN growth. It is shown that it is possible to control the polarity of GaN by means of appropriate choice of the growth under conditions with N or Ga enrichment at the initial stage of GaN/Si(111) epitaxy.