ZnO Doping and Defect Engineering—A Review

Optical and Structural Characterization of Cd-Free Buffer Layers Fabricated by Chemical Bath Deposition

“…Mursal et al [76], reported the optical band gap of ZnO thin films varying between 3.82 and 3.69 eV deposited by the sol-gel spin-coating method after changed the sintering temperature. The difference in the experimental and theorical band gap is attributed to the intrinsic defects in ZnO (e.g., O vacancy (V O ), Zn vacancy (V Zn ), Zn interstitial (Zn i ), O interstitial (O i ) and anti-site Zn (Zn O )) [77][78][79]. Table 1 shows that the coating's band gap changes between 3.…”

Defects in complex oxide thin films for electronics and energy applications: challenges and opportunities

“…305,306 Despite its intrinsic advantages, the lack of control over dopants and defects hindered its further application to practical devices, thus stimulated a boom over investigating the defect chemistry in ZnO. 302,[307][308][309][310] The as-grown ZnO crystals normally exhibit n-type conductivity, which was initially attributed to the native defects such as Zn interstitials, Zn vacancies or V O (Fig. 12a).…”

Modulating the growth of chemically deposited ZnO nanowires and the formation of nitrogen- and hydrogen-related defects using pH adjustment

“…a Zn-rich or O-rich environment, would lead to the formation of oxygen or zinc 𝜇 𝑂 vacancies, respectively. 25,26 Simultaneously, regarding the growth of ZnO via solution methods, the pH also has a relationship with 27,28 which consequently affects the formation energy of intrinsic and 𝜇 𝑂 , extrinsic point defects. 29 Through the paramount contribution of Van de Walle, 30 it was revealed from DFT calculations that interstitial hydrogen (H i ) systematically acts as a shallow donor over the expected range of the Fermi level, which is different from the typical amphoteric behavior that hydrogen impurities exhibit in other semiconductors.…”