Extra-Low Temperature Growth of ZnO by Atomic Layer Deposition with Diethylzinc Precursor

ZnO thin films were grown on silicon substrate by atomic layer deposition method. We explored double-exchange chemical reaction and used very volatile and reactive diethylzinc as a zinc precursor. These enables us to obtain zinc oxide thin films of high quality at extremely low growth temperature (90-200ºC). The films are polycrystalline as was determined by X-ray diffraction and show flat surfaces with roughness of 1-4 nm as derived from atomic force microscopy measurements. Photoluminescence studies show that an edge emission of excitonic origin is observed even at room temperature for all investigated ZnO layers deposited with the diethylzinc precursor.