. ▁In ▁the ▁mass - transport - limited ▁growth ▁regime ▁in ▁which ▁MO C VD ▁react ors ▁typically ▁operate , ▁growth ▁is ▁driven ▁by ▁su pers atur ation ▁of ▁chemical ▁species ▁in ▁the ▁v apor ▁phase . ▁MO C VD ▁can ▁grow ▁films ▁containing ▁combinations ▁of ▁group ▁III ▁and ▁group ▁V , ▁group ▁II ▁and ▁group ▁VI , ▁group ▁IV . ▁ ▁Re quired ▁py ro ly s is ▁temperature ▁increases ▁with ▁increasing ▁chemical ▁bond ▁strength ▁of ▁the ▁prec ursor . ▁ ▁The ▁more ▁carbon ▁atoms ▁are ▁attached ▁to ▁the ▁central ▁metal ▁atom , ▁the ▁we aker ▁the ▁bond . ▁The ▁diffusion ▁of ▁atoms ▁on ▁the ▁substr ate ▁surface ▁is ▁affected ▁by ▁atomic ▁steps ▁on ▁the ▁surface . ▁ ▁The ▁v apor ▁pressure ▁of ▁the ▁group ▁III ▁metal ▁organ ic ▁source ▁is ▁an ▁important ▁control ▁parameter ▁for ▁MO C VD ▁growth , ▁since ▁it ▁determ ines ▁the ▁growth ▁rate ▁in ▁the ▁mass - transport - limited ▁regime . ▁ ▁Re actor ▁components ▁ ▁In ▁the ▁metal ▁organ ic ▁chemical ▁v apor ▁de position ▁( MO C VD ) ▁technique , ▁react ant ▁g ases ▁are ▁combined ▁at ▁elev ated ▁temper atures ▁in ▁the ▁re actor ▁to ▁cause ▁a ▁chemical ▁interaction , ▁resulting ▁in ▁the ▁de position ▁of ▁materials ▁on ▁the ▁substr ate . ▁ ▁A ▁re actor ▁is ▁a ▁chamber ▁made ▁of ▁a ▁material ▁that ▁does ▁not ▁react ▁with ▁the ▁chemical s ▁being ▁used . ▁It ▁must ▁also ▁with stand ▁high ▁temper atures . ▁This ▁chamber ▁is ▁composed ▁by ▁re actor ▁walls ,