Effective Oxygen-Defect Passivation in ZnO Thin Films Prepared by Atomic Layer Deposition Using Hydrogen Peroxide

Abstract

The intrinsic oxygen-vacancy defects in ZnO have prevented the preparation of p-type ZnO with high carrier concentration. Therefore, in this work, the effect of the concentration of H 2 O 2 (used as an oxygen source) on the oxygen-vacancy concentration in ZnO prepared by atomic layer deposition was investigated. The results indicated that the oxygen-vacancy concentration in the ZnO film decreased by the oxygen-rich growth conditions when using H 2 O 2 as the oxygen precursor instead of a conventional oxygen source such as H 2 O. The suppression of oxygen vacancies decreased the carrier concentration and increased the resistivity. Moreover, the growth orientation changed to the (002) plane, from the combined (100) and (002) planes, with the increase in H 2 O 2 concentration. The passivation of oxygen-vacancy defects in ZnO can contribute to the preparation of p-type ZnO.

Tuning intrinsic defects in ZnO films by controlling the vacuum annealing temperature: an experimental and theoretical approach

“…As can be seen, the I (100)/ I (002) ratio shows a slight trend to decrease as the annealing temperature increases, suggesting the increase in the (002) preferential orientation of the ZnO films with the annealing temperature. According to the literature the latter trend results from the increase of anionic vacancies (oxygen vacancies) due to the poor-oxygen condition [36]. It seems to be consistent with that reported by Abdallah et al, who showed that an oxygen-rich environment promotes the non-polar (100) preferred orientation at the expense of the polar (002) orientation [37].…”

Subthreshold Conduction of Disordered ZnO-Based Thin-Film Transistors

“…Please note that the ZnO films exhibit the typical polycrystalline structure, which was mainly oriented to the (002) direction (34.50°) as in Figure S1a . For the wurtzite-structure ZnO, the c-axis (002) plane has been known as the most densely packed and thermodynamically stable orientation [ 29 , 30 ]. We conducted the XRD analysis of the ZnO film using the stacked structure as in the inset of Figure S1 , because of the penetration depth.…”