Hu-Jie Jin

Analysis of Photoluminescence for N-doped and undoped p-type ZnO Thin Films Fabricated by RF Magnetron Sputtering Method

N-doped ZnO thin films were deposited on n-type Si(100) and homo-buffer layer, and undoped ZnO thin film was also deposited on homo-buffer layer by RF magnetron sputtering method. After deposition, all films were in-situ annealed at for 5 minutes in ambient of with pressure of 10Torr. X -ray diffraction shows that the homo-buffer layer is beneficial to the crystalline of N-doped ZnO thin films and all films have preferable c-axis orientation. Atomic force microscopy shows that undoped ZnO thin film grown on homo-buffer layer has an evident improvement of smoothness compared with N-dope ZnO thin films. Hall-effect measurements show that all ZnO films annealed at possess p-type conductivities. The undoped ZnO film has the highest carrier concentration of . The photoluminescence spectra show the emissions related to FE, DAP and many defects such as , , and . The p-type defects (, , and ) are dominant. The undoped ZnO thin film has a better p-type conductivity compared with N-doped ZnO thin film.

Implementation of High Carrier Mobility in Al-N Codoped p-Type ZnO Thin Films Fabricated by Direct Current Magnetron Sputtering with ZnO:Al 2 O 3 Ceramic Target

In this study, Al-N codoped p-type zinc oxide (ZnO) thin films were deposited on Si and homo-buffer layer templates in a mixture of and gas with ceramic ZnO:(2 wt% ) as a sputtering target using DC- magnetron sputtering. X-ray diffraction spectra of two-theta diffraction showed that all films have a predominant (002) peak of ZnO Wurtzite structure. As the fraction in the mixed and gases increased, field emission secondary electron microscopy revealed that the surface appearance of codoped films on Si varied from smooth to textured structure. The p-type ZnO thin films showed carrier concentration in the range of , resistivity in the range of 131.2-2.864 , and mobility in the range of respectively.

PL Property of Al-N Codoped p-type ZnO Thin Films Fabricated by DC Magnetron Sputtering

High-quality Al-N doped p-type ZnO thin films were deposited on Si and buffer layer/Si by DC magnetron sputtering in a mixture of and gas. The target was ceramic ZnO mixed with (2 wt%). The p-type ZnO thin films showed a carrier concentration in the range of , resistivity in the range of 131.22.864 , mobility in the range of 3.9931.6 , respectively. It was easier to dope p-type ZnO films on Si substrates than on buffer layer/Si. The film grown on Si showed the highest quality of photoluminescence (PL) characteristics. The Al donor energy level depth of Al-N codoped ZnO films was reduced to about 50 meV, and the N acceptor energy level depth was reduced to 63 meV.

Analysis of Electrical Property of Room Temperature-grown ZnO:Al Thin films Annealed in Hydrogen Ambient

In this paper, to establish growth technology of ZnO:Al thin films at low temperature applied to photoelectronic devices, ZnO:Al were prepared by RF magnetron sputtering on glass substrate at room temperature using different RF power with subsequent annealing process at different temperature in ambient. The resistivity of hydrogen-annealed ZnO:Al thin film at temperature of was reduced to from which was optimal value for as-grown films. X-ray photoelectron spectroscopy(XPS) revealed that improved electrical properties are ascribed to desorption of the negatively charged oxygen species from the grain boundary surfaces by the hydrogen annealing process.

Analysis of microstructure and electrical properties of Al-doped p-type ZnO thin films

We present the Al-doped p-type ZnO thin films fabricated by RF magnetron sputtering on n-Si (100) and homo-buffer layers in pure oxygen ambient. Al₂O₃ 2wt%-mixed ZnO ceramic was selected as a sputtering target. XRD spectra show that the Al-doped ZnO thin films have ZnO crystal structure. Hall Effect experiments show that p-type carrier concentrations are arranged from 1.66times10¹⁶ to 4.04times10¹⁸ cm^-3, mobility from 0.194 to 198 cm² V^-1 s^-1 and resistivity from 0.0963 to 18.4 Omegacm. FESEM cross-sectional images show compact structure of a p- type ZnO:Al thin film annealed at 800degC with mass density of 5.40 g/cm³ which is smaller than that of theoretical value of 5.67 g/cm³.I-V curve of p-n junction shows rectifying feature with turn-on voltage of 1.8 V.

Realization and Analysis of p-Type ZnO:Al Thin Film by RF Magnetron Sputtering

Al-doped p-type ZnO thin films were fabricated by RF magnetron sputtering on n-Si (100) and homo-buffer layers in pure oxygen ambient. ZnO ceramic mixed with 2 wt% was selected as a sputtering target. XRD spectra show that the Al-doped ZnO thin films have ZnO crystal structure. Hall Effect experiments with Van der Pauw configuration show that p-type carrier concentrations are arranged from to , mobilities from 0.194 to and resistivities from 0.0963 to . FESEM cross section images of different parts of a p-type ZnO:Al thin film annealed at show a compact structure. Measurement for same sample shows that density is which is smaller than theoretically calculated value of . Photoluminescence (PL) spectra at 10 K show a shoulder peak of p-type ZnO film at about 3.117 eV which is ascribed to electron transition from donor level to acceptor level (DAP).

Defect Analysis via Photoluminescence of p-type ZnO:N Thin Film fabricated by RF Magnetron Sputtering

ZnO is a promising material to make high efficient ultraviolet(UV) or blue light emitting diodes(LEDs) because of its large binding energy and energy bandgap. In this study, we prepared ZnO thin films with p-type conductivity on silicon(100) substrates by RF magnetron sputtering in the mixture of and . The process was accompanied by low pressure in-situ annealing in at and respectively. Hall effect in Van der Pauw configuration showed that the N-doped ZnO film annealed at has p-type conductivity. Photoluminescence(PL) spectrum of the film annealed at showed UV emission related to exciton and bound to donor-acceptor pair(DAP) as well as visible emission related to many intrinsic defects.

The Increase of Photodiode Efficiency by using Transparent Conductive Aluminium-doped Zinc Oxide Thin Film

In this paper, to increase the light current efficiency of photodiode, we fabricated aluminum-doped zinc oxide(AZO) thin films by RF magnetron sputtering. AZO thin films were deposited at low temperature of 100 and different RF powers of 50, 100, 150 and 200 W due to selective process technology. Then the AZO thin films were annealed at 400 for 1 hr in vacuum ambient to increase crystalline. The lowest resistivity of 1.35 and a high transmittance over 90 % were obtained under the conditions of 3 mTorr, 100 `c and 150 W. The optimized AZO thin films were deposited as anti-reflection coating on PN junction of silicon photodiode. It was confirmed by the result of curve that the efficiency of photodiode with AZO thin film was enhanced 17 % more than commercial photodiode.

V-I Curves of p-ZnO:Al/n-ZnO:Al Junction Fabricated by RF Magnetron Sputtering

Al-doped p-type ZnO films were fabricated on n-Si (100) and homo-buffer layers in pure oxygen at of by RF magnetron sputtering. Target was ZnO ceramic mixed with 2 wt% . XRD spectra show that the Al-doped ZnO thin films have ZnO crystal structure and homo-buffer layers are beneficial to Al-doped ZnO films to grow along c-axis. Hall Effect experiments with Van der Pauw configuration show that p-type carrier concentrations are ranged from to , mobilities from 0.194 to and resistivities from 7.97 to . p-type sample has density of which is smaller than theoretically calculated value of . XPS spectra show that Ols has O-O and Zn-O structures and Al2p has only Al-O structure. P-ZnO:Al/n-ZnO:Al junctions were fabricated by magnetron sputtering. V-I curves show that the p-n junctions have rectifying characteristics.

Defect analysis of N-doped p-type ZnO film fabricated by magnetron sputtering via photoluminescence spectra

ZnO is a promising material to make high efficient ultraviolet (UV) or blue light emitting diodes (LEDs) due to its large binding energy and energy bandgap. In present study, we prepared an N-doped p-type ZnO thin film on (100) silicon substrate by RF magnetron sputtering in the mixture ambient of N2 and O2. accompanying with in-situ annealing at low pressure of 10Torr in O2 at 800degC. Photoluminescence (PL) analysis of the film showed UV emission related to exciton and donor-acceptor pair transition (DAP) and visible emission related to various kinds of defects. Via PL spectra analysis the reason of p-type conversion of ZnO thin film can be explained, which is in favor of getting high quality p-type ZnO films.