Self-limiting nature of atomic layer epitaxy of wurtzite thin films obtained from sequentially pressurized Zn(CH2CH3) 2 and H2O vapor pulses on sapphire (001) substrates

Abstract

The atomic layer epitaxy of wurtzite thin films on sapphire (001) substrates was studied in the controlled growth of zinc oxide films by sequential surface chemical reactions using a vapor combination of diethylzinc (Zn(CH2CH3)2) and water (H2O). The optical constant and thickness of these wurtzite films were investigated in terms of the Zn(CH2CH3)2 and H2O vapor pressures using a variable-angle spectroscopic ellipsometer. As a result, the self-limiting nature of the atomic layer epitaxy of wurtzite thin films was demonstrated successfully under various conditions of the dosing reactant vapors, whereby the growth rate was almost constant at approximately 0.26 nm/cycle (2.6 nm/min) and the index of refraction was also constant at 1.94. © Published under licence by IOP Publishing Ltd.