“…The growth of GaAs by HVPE involves gaseous chloride GaCl molecules synthesized inside the reactor by the use of an HCl flow reacting with a Ga metallic source, and arsine gas (AsH 3 ) which is completely decomposed into (As 2 , As 4 ) gaseous molecules when entering the hot wall reactor [20,21]. The global growth reaction for GaAs in an H 2 atmosphere is…”