Microstructure and optical properties of ZnO:Al films prepared by radio frequency reactive magnetron sputtering

Concentration-dependent behavior of hydrogen in Al-doped ZnO thin films

“…The Al 3+ substitute is an accepter. Therefore, Zn i might decrease with the decrease in Al 3+ substitute, because ZnO is a self-assembled oxide compound [14,15]. Thus, this observation also confirms our speculation that the introducing of H reduced the solubility of substitutional Al.…”

“…3, the Stokes shift increases and no change of band gap energy can be observed in Fig. 4, indicating the gradual decrease in carrier concentration as the continually introducing of H. A reasonable explanation for this is that the introducing of H reduced the solubility of the substitutional Al, even though all the films were deposited from the precursor solutions with constant Al:Zn atomic ratio of up to 4:100 [14,15]. Therefore, the influence of introduced H on Al concentration should be directly responsible for the decrease in carrier concentration.…”

The evolution behavior of structures and photoluminescence of K-doped ZnO thin films under different annealing temperatures

“…There are three main viewpoints as follows. (1) The electron transition from Zn interstitial levels to the top of valence band leads to the blue emission [31][32][33][34]; (2) the electron transition from V O to valence band leads to the blue emission [35]; (3) the electron transition from the bottom of conduction band to Zn vacancy levels leads to the blue emission [29,36]. It is worthy to be mentioned that Zeng et al [32] recently prepared ZnO nanoparticles based on non-equilibrium process and found that these ZnO nanoparticles have very strong blue emissions.…”

Microstructure and blueshift in optical band gap of nanocrystalline AlxZn1−xO thin films

“…Fig. 10 shows the room temperature PL spectra of undoped and Al Zn interstitial levels to the top of valence band [41][42][43][44]; (b) the electron transition from V 0 to valence band [45]; (c) the electron transition from the bottom of conduction band to Zn vacancy levels [39,46]. The sharp UV emission peak around 3.29 eV presumably results from excitons.…”