Self-limiting transformation of monodisperse Ga droplets into GaAs nanocrystals

GaAs nanocrystals, of approximate diameter 10 nm, have been produced and deposited on various substrates. The fabrication route allows the production of nanocrystals with a very narrow size distribution. It utilizes the formation of ultrafine Ga particles and their self-limiting reaction with arsine at elevated temperatures. The kinetics of the reaction of Ga to produce GaAs depends on the temperature and the arsine flow. The temperature at which the reaction began was found to be as low as 200 degrees C. Our approach opens the possibility to produce size-selected nanocrystals of compound semiconductors in a simple, reliable, and efficient way. (C) 1996 American Institute of Physics.