Study of Gas-Phase Parasitic Reaction Pathways for ZnO Thin Film Grown by MOCVD
This study utilized density functional theory(DFT)in quantum chemistry to investigate the gas-phase parasitic reaction mechanism between diethylzinc(DEZn)and tert-butanol(t-BuOH)during the metal-organic chemical vapor deposition(MOCVD)growth process of ZnO thin films.By calculating the Gibbs free energy changes along various reaction pathways at different temperatures,a comprehensive thermodynamic evaluation of key intermediates(HOZnOBut,H(ZnO)2But,HZnOH),as well as the formation of dimers(Zn2O2H4,Zn2O4H4,Zn4O4H4),and trimers(Zn3O6H6)was performed.The main objective was to identify potential pathways and products that could lead to the formation of nanoparticles,which might impede ZnO thin film growth.Research has shown that under high-temperature deposition conditions(673.15 K＜T＜713.15 K),the intermediate product H(ZnO)2 But resulting from the thermal decomposition of DEZn readily reacts with H2O to form(ZnOH)2,supporting ZnO thin film growth.However,these intermediates can also undergo polymerization elimination reactions to generate dimers and trimers,serving as crucial precursors for nanoparticle formation.Notably,the most favorable pathway involved the formation of Zn2 O4 H4 through the polymerization of(HOZnOBut)2 followed by the elimination of C4 H8.Therefore,the dimer Zn2O4H4 emerged as a crucial precursor for nanoparticle formation.
ZnOmetal organic chemical vapor depositiondensity functional theoryparasitic reactionthin filmdimer
万方数据
维普
