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Room-temperature electrically pumped near-infrared random lasing from high-quality m-plane ZnO-based metal-insulator-semiconductor devices.

Chen C, Wang T, Wu H, Zheng H, Wang J, Xu Y, Liu C - Nanoscale Res Lett (2015)

Bottom Line: Epitaxial m-plane ZnO thin films have been deposited on m-plane sapphire substrates at a low temperature of 200°C by atomic layer deposition.Moreover, the residual strain along the ZnO [-12-10] direction is released.It is interesting to observe the near-infrared random lasing from the metal-insulator-semiconductor devices.

View Article: PubMed Central - PubMed

Affiliation: Key Laboratory of Artificial Micro- and Nano-structures of Ministry of Education, School of Physics and Technology, Wuhan University, Wuhan, 430072 People's Republic of China.

ABSTRACT
Epitaxial m-plane ZnO thin films have been deposited on m-plane sapphire substrates at a low temperature of 200°C by atomic layer deposition. A 90° in-plane rotation is observed between the m-plane ZnO thin films and the sapphire substrates. Moreover, the residual strain along the ZnO [-12-10] direction is released. To fabricate metal-insulator-semiconductor devices, a 50-nm Al2O3 thin film is deposited on the m-plane ZnO thin films. It is interesting to observe the near-infrared random lasing from the metal-insulator-semiconductor devices.

No MeSH data available.


Related in: MedlinePlus

O 1 sXPS spectra and PL spectra of the ZnO thin films. (a) O 1 s XPS spectra of the ZnO thin films. Dots are the experimental data and lines are the fitting results. (b) The PL spectra of the ZnO thin films before and after depositing a 50-nm Al2O3 cap layer. The inset of (b) is the magnified area of the PL spectra from 450 to 600 nm.
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Fig4: O 1 sXPS spectra and PL spectra of the ZnO thin films. (a) O 1 s XPS spectra of the ZnO thin films. Dots are the experimental data and lines are the fitting results. (b) The PL spectra of the ZnO thin films before and after depositing a 50-nm Al2O3 cap layer. The inset of (b) is the magnified area of the PL spectra from 450 to 600 nm.

Mentions: In order to analyze the chemical compositions and the defect states of the ZnO thin films, XPS measurement was performed. From the statistical results of XPS, the atom ratio of Zn:O is about 1.06:1, in which it can be observed that the ZnO thin films are a little Zn-rich. Figure 4a shows the O 1 s XPS spectra of the ZnO films. The binding energies of the XPS spectra have been calibrated by taking the carbon C 1 s peak (284.5 eV) as a reference. The O 1 s peak is deconvoluted into three peaks at 529.8, 530.9, and 531.9 eV by using Gaussian fitting. The peaks centered at 529.8 and 530.9 eV are assigned to oxygen atoms in the oxide lattice without and with oxygen vacancies, respectively. The peak at 531.9 eV is usually attributed to chemisorbed oxygen on the surface of ZnO thin films, such as carbonyl and hydroxyl groups. The relative integrated intensity percentages of the different oxygen species calculated from fitting peaks are used to analyze the quantities of the oxygen lattice, oxygen vacancy, and hydroxyl group [22,23]. The percentages of peaks centered at 529.8, 530.9, and 531.9 eV are 69.53%, 16.68%, and 13.8%, respectively. Compared with the XPS results from other works [23,24], our ZnO films have a high percentage of the oxygen lattice-related peak and a small ratio of the oxygen vacancy-related peak. Therefore, from the XPS results, it can be concluded that there are only a few oxygen vacancies in the ZnO thin films deposited at 200°C by ALD.Figure 4


Room-temperature electrically pumped near-infrared random lasing from high-quality m-plane ZnO-based metal-insulator-semiconductor devices.

Chen C, Wang T, Wu H, Zheng H, Wang J, Xu Y, Liu C - Nanoscale Res Lett (2015)

O 1 sXPS spectra and PL spectra of the ZnO thin films. (a) O 1 s XPS spectra of the ZnO thin films. Dots are the experimental data and lines are the fitting results. (b) The PL spectra of the ZnO thin films before and after depositing a 50-nm Al2O3 cap layer. The inset of (b) is the magnified area of the PL spectra from 450 to 600 nm.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
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getmorefigures.php?uid=PMC4385150&req=5

Fig4: O 1 sXPS spectra and PL spectra of the ZnO thin films. (a) O 1 s XPS spectra of the ZnO thin films. Dots are the experimental data and lines are the fitting results. (b) The PL spectra of the ZnO thin films before and after depositing a 50-nm Al2O3 cap layer. The inset of (b) is the magnified area of the PL spectra from 450 to 600 nm.
Mentions: In order to analyze the chemical compositions and the defect states of the ZnO thin films, XPS measurement was performed. From the statistical results of XPS, the atom ratio of Zn:O is about 1.06:1, in which it can be observed that the ZnO thin films are a little Zn-rich. Figure 4a shows the O 1 s XPS spectra of the ZnO films. The binding energies of the XPS spectra have been calibrated by taking the carbon C 1 s peak (284.5 eV) as a reference. The O 1 s peak is deconvoluted into three peaks at 529.8, 530.9, and 531.9 eV by using Gaussian fitting. The peaks centered at 529.8 and 530.9 eV are assigned to oxygen atoms in the oxide lattice without and with oxygen vacancies, respectively. The peak at 531.9 eV is usually attributed to chemisorbed oxygen on the surface of ZnO thin films, such as carbonyl and hydroxyl groups. The relative integrated intensity percentages of the different oxygen species calculated from fitting peaks are used to analyze the quantities of the oxygen lattice, oxygen vacancy, and hydroxyl group [22,23]. The percentages of peaks centered at 529.8, 530.9, and 531.9 eV are 69.53%, 16.68%, and 13.8%, respectively. Compared with the XPS results from other works [23,24], our ZnO films have a high percentage of the oxygen lattice-related peak and a small ratio of the oxygen vacancy-related peak. Therefore, from the XPS results, it can be concluded that there are only a few oxygen vacancies in the ZnO thin films deposited at 200°C by ALD.Figure 4

Bottom Line: Epitaxial m-plane ZnO thin films have been deposited on m-plane sapphire substrates at a low temperature of 200°C by atomic layer deposition.Moreover, the residual strain along the ZnO [-12-10] direction is released.It is interesting to observe the near-infrared random lasing from the metal-insulator-semiconductor devices.

View Article: PubMed Central - PubMed

Affiliation: Key Laboratory of Artificial Micro- and Nano-structures of Ministry of Education, School of Physics and Technology, Wuhan University, Wuhan, 430072 People's Republic of China.

ABSTRACT
Epitaxial m-plane ZnO thin films have been deposited on m-plane sapphire substrates at a low temperature of 200°C by atomic layer deposition. A 90° in-plane rotation is observed between the m-plane ZnO thin films and the sapphire substrates. Moreover, the residual strain along the ZnO [-12-10] direction is released. To fabricate metal-insulator-semiconductor devices, a 50-nm Al2O3 thin film is deposited on the m-plane ZnO thin films. It is interesting to observe the near-infrared random lasing from the metal-insulator-semiconductor devices.

No MeSH data available.


Related in: MedlinePlus