“…However, the present study, as well as other recent works (9,12,14), suggests that the growth rate is related to the partial pressure of the individual reactants, GaC1 and AsH3 or As4, rather than to the Ga/As gas ratio. Since increasing AsH8 flow rates increase the growth rate, in accord with thermodynamic expectations, and increasing HCI flow rates decrease the growth rate, contrary to equilibrium thermodynamics (17), it appears that GaC1 is the chemical species limiting the growth rate. This could arise at high HC1 flow rates by nearly complete filling of adsorption sites with GaC1 on the crystal surface, to the exclusion of the As-species.…”