Influence of phosphine flow rate on Si growth rate in gas source molecularbeam epitaxy

As reported by other authors, we have also observed that the Si growth rate decreases with increasing phosphine (PH3) flow rate in gas source-Si molec ular beam epitaxy using phosphorous (P) as a n-type dopant. Why small quant ity PH3 can affect Si growth rate? Up to now, the quantitative characteriza tion of PH3 flow influence on Si growth rate is little known. In this lette r, the PH, influence will be analyzed in detail and a model considering str ong P surface segregation and its absorption of hydrogen will be proposed t o characterize the effect. (C) 2000 Elsevier Science B.V. All rights reserv ed.