Transport mechanisms in Co-doped ZnO (ZCO) and H-irradiated ZCO polycrystalline thin films

2021 ◽  
Vol 23 (3) ◽  
pp. 2368-2376
Author(s):  
A. Di Trolio ◽  
A. Amore Bonapasta ◽  
C. Barone ◽  
A. Leo ◽  
G. Carapella ◽  
...  
Keyword(s):  
Thin Films ◽  
Opposite Effect ◽  
Transport Mechanisms ◽  
Co Doping ◽  
Polycrystalline Thin Films ◽  
Doped Zno ◽  
Co Doped

Co doping increases the ZnO resistivity (ρ) at high T (HT), whereas it has an opposite effect at low T (LT). H balances the Co effects by neutralizing the ρ increase at HT and strengthening its decrease at LT.

Raman spectroscopy of V and Co doped ZnO ceramics and thin films

2004 ◽  
Vol 829 ◽  
Author(s):  
K. Samanta ◽  
N. Awasthi ◽  
B. Sundarakannan ◽  
P. Bhattacharya ◽  
R. S. Katiyar
Keyword(s):  
Thin Films ◽  
Raman Spectra ◽  
Processing Route ◽  
Secondary Phases ◽  
Axis Orientation ◽  
Co Doping ◽  
Electronic Raman Scattering ◽  
Doped Zno ◽  
Integrated Intensities ◽  
Co Doped

ABSTRACTLattice dynamical and electronic transition changes due to V and Co doped ZnO have been investigated using optical techniques. Vanadium and Co doped ZnO pellets were prepared using conventional ceramic processing route and thin films were fabricated by pulsed laser deposition. Raman spectra of Zn1-xVxO targets showed many additional peaks in the range of 230 to 350 cm-1 and 750 to 900 cm-1. Integrated intensities of these additional modes decreased with increase of temperature as similar to the host ZnO modes, which precludes electronic Raman scattering to be the origin. Raman peaks for stoichiometric Zn3(VO4)2 and Zn2V2O7 compounds also had additional peaks that can be attributed to the secondary phases formed in the compositions of Zn1-xVxO. Raman spectra of Zn1-xCoxO showed no additional modes besides ZnO modes, however, the intensity of the second order peak at 540 cm-1 was increased due to Co doping. Thin films of Zn1-xCoxO exhibited highly c-axis orientation deposited on (001)Al2O3 substrates. The optical absorption of the films showed that the band gap decreased with increase of Co concentrations at room temperature along with the sub bandgap absorptions due to d-d transitions of Co2+.

Ga-Sn Co-Doped ZnO Films via Sol-Gel Route

2018 ◽  
Vol 280 ◽  
pp. 43-49
Author(s):  
Zi Neng Ng ◽  
Kah Yoong Chan
Keyword(s):  
Thin Films ◽  
Electrical Properties ◽  
Band Gap ◽  
Doping Concentration ◽  
Sol Gel ◽  
Zno Films ◽  
Axis Orientation ◽  
Co Doping ◽  
Doped Zno ◽  
Co Doped

Zinc oxide (ZnO) has gained worldwide attention due to its direct wide band gap and large exciton binding energy, which are important properties in the application of emerging optoelectronic devices. By doping ZnO with donor elements, a combination of good n-type conductivity and good transparency in the visible and near UV range can be achieved. Co-doping ZnO with several types of dopants is also beneficial in improving the electronic properties of ZnO films. To the best of our knowledge, the fundamental properties of gallium-tin (Ga-Sn) co-doped ZnO (GSZO) films were rarely explored. In this work, we attempt to coat GSZO films on glass substrates via sol-gel spin-coating method. The Ga-Sn co-doping ratio was fixed at 1:1 and the concentration of the dopants was varied at 0.5, 1.0, 1.5, and 2 at.% with respect to the precursor. The AFM image show granular features on the morphology of all GSZO films. All samples also exhibit a preferential c-axis orientation as detected by XRD. The XRD indicates higher crystal quality and larger crystallite size on GSZO thin films at 2.0 at.% and agrees well with the AFM results. However, the transparency and optical band-gap of the GSZO thin films degrade with higher co-doping concentration. The best electrical properties were achieved at co-doping concentration of 1 at.% with conductivity and carrier density of 7.50 × 10-2S/cm and 1.37 × 1016cm-3, respectively. At 1.0 at.% co-doping concentration, optimal optical transmittance and electrical properties were achieved, making it promising in the application of optoelectronics.

scholarly journals Enhanced Electrical Properties and Stability of P-Type Conduction in ZnO Transparent Semiconductor Thin Films by Co-Doping Ga and N

Coatings ◽  
2020 ◽  
Vol 10 (11) ◽  
pp. 1069
Author(s):  
Chien-Yie Tsay ◽  
Wan-Yu Chiu
Keyword(s):  
Thin Films ◽  
Hole Concentration ◽  
Sol Gel ◽  
Co Doping ◽  
Semiconductor Thin Films ◽  
Doped Zno ◽  
Transparent Semiconductor ◽  
P Type ◽  
Type Conduction ◽  
Co Doped

P-type ZnO transparent semiconductor thin films were prepared on glass substrates by the sol-gel spin-coating process with N doping and Ga–N co-doping. Comparative studies of the microstructural features, optical properties, and electrical characteristics of ZnO, N-doped ZnO (ZnO:N), and Ga–N co-doped ZnO (ZnO:Ga–N) thin films are reported in this paper. Each as-coated sol-gel film was preheated at 300 °C for 10 min in air and then annealed at 500 °C for 1 h in oxygen ambient. X-ray diffraction (XRD) examination confirmed that these ZnO-based thin films had a polycrystalline nature and an entirely wurtzite structure. The incorporation of N and Ga–N into ZnO thin films obviously refined the microstructures, reduced surface roughness, and enhanced the transparency in the visible range. X-ray photoelectron spectroscopy (XPS) analysis confirmed the incorporation of N and Ga–N into the ZnO:N and ZnO:Ga–N thin films, respectively. The room temperature PL spectra exhibited a prominent peak and a broad band, which corresponded to the near-band edge emission and deep-level emission. Hall measurement revealed that the ZnO semiconductor thin films were converted from n-type to p-type after incorporation of N into ZnO nanocrystals, and they had a mean hole concentration of 1.83 × 1015 cm−3 and a mean resistivity of 385.4 Ω·cm. In addition, the Ga–N co-doped ZnO thin film showed good p-type conductivity with a hole concentration approaching 4.0 × 1017 cm−3 and a low resistivity of 5.09 Ω·cm. The Ga–N co-doped thin films showed relatively stable p-type conduction (>three weeks) compared with the N-doped thin films.

Influence of N Dopant on the Electric and Magnetic Properties of Co Doped ZnO Thin Films

2010 ◽  
Vol 25 (7) ◽  
pp. 711-716 ◽  
Author(s):  
Xue-Tao WANG ◽  
Li-Ping ZHU ◽  
Zhi-Gao YE ◽  
Zhi-Zhen YE ◽  
Bing-Hui ZHAO
Keyword(s):  
Thin Films ◽  
Magnetic Properties ◽  
Zno Thin Films ◽  
Doped Zno ◽  
Co Doped

scholarly journals Photo-activity and low resistivity in N/Nb Co-doped TiO2 thin films by combinatorial AACVD

2016 ◽  
Vol 4 (2) ◽  
pp. 407-415 ◽  
Author(s):  
Nicholas P. Chadwick ◽  
Emily N. K. Glover ◽  
Sanjayan Sathasivam ◽  
Sulaiman N. Basahel ◽  
Shaeel A. Althabaiti ◽  
...  
Keyword(s):  
Thin Films ◽  
Functional Properties ◽  
Tio2 Thin Films ◽  
Doped Tio2 ◽  
Low Resistivity ◽  
Co Doping ◽  
Co Doped

Combinatorial AACVD has achieved the production of various niobium/nitrogen co-doped TiO2 materials in a single film. The co-doping concentrations have been correlated with functional properties.

Magnetic anisotropy in nanocrystalline Co-doped ZnO thin films

2010 ◽  
Vol 487 (1-3) ◽  
pp. 97-100 ◽  
Author(s):  
M. Subramanian ◽  
M. Tanemura ◽  
T. Hihara ◽  
V. Ganesan ◽  
T. Soga ◽  
...  
Keyword(s):  
Thin Films ◽  
Magnetic Anisotropy ◽  
Zno Thin Films ◽  
Doped Zno ◽  
Co Doped

Enhancement of Nonlinear Absorption in Defect Controlled ZnO Polycrystalline Thin Films by Means of Co‐Doping

2021 ◽  
pp. 2000539
Author(s):  
Bekir Asilcan Ünlü ◽  
Deniz Sener ◽  
Sezen Tekin ◽  
Elif Akhuseyin Yildiz ◽  
Ahmet Karatay ◽  
...  
Keyword(s):  
Thin Films ◽  
Nonlinear Absorption ◽  
Co Doping ◽  
Polycrystalline Thin Films

Structural and Magnetic Properties of Mn/Fe co-Doped ZnO Thin Films Prepared by Sol–Gel Technique

2014 ◽  
Vol 50 (8) ◽  
pp. 1-4 ◽  
Author(s):  
Robina Ashraf ◽  
Saira Riaz ◽  
Mahwish Bashir ◽  
Usman Khan ◽  
Shahzad Naseem
Keyword(s):  
Thin Films ◽  
Magnetic Properties ◽  
Sol Gel ◽  
Zno Thin Films ◽  
Gel Technique ◽  
Structural And Magnetic Properties ◽  
Doped Zno ◽  
Co Doped

Effect of cobalt doping on microstructures and dielectric properties of ZnO

2019 ◽  
Vol 97 (3) ◽  
pp. 227-232 ◽  
Author(s):  
Ye Zhao ◽  
Fan Tong ◽  
Mao Hua Wang
Keyword(s):  
Zno Nanoparticles ◽  
Sol Gel ◽  
Hexagonal Wurtzite Structure ◽  
Sem Analysis ◽  
Co Doping ◽  
In Doping ◽  
Zno Powders ◽  
Doped Zno ◽  
Zno Crystal ◽  
Co Doped

Pure and cobalt-doped ZnO nanoparticles (2.5, 5, 7.5, and 10 atom % Co) are synthesized by sol–gel method. The as-synthesized nanoparticles are characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and field emission scanning electron microscopy (FE-SEM) analysis. The nanoparticles of 0, 2.5, and 5 atom % Co-doped ZnO exhibited hexagonal wurtzite structure and have no other phases. Moreover, the (101) diffraction peaks position of Co-doped ZnO shift toward a smaller value of diffraction angle compared with pure ZnO powders. The results confirm that Co ions were well incorporated into ZnO crystal lattice. Simultaneously, Co doping also inhibited the growth of particles, and the crystallite size decreased from 43.11 nm to 36.63 nm with the increase in doping concentration from 0 to 10 atom %. The values of the optical band gap of all Co-doped ZnO nanoparticles gradually decreased from 3.09 eV to 2.66 eV with increasing Co content. Particular, the dielectric constant of all Co-doped ZnO ceramics gradually increased from 1.62 × 103 to 20.52 × 103, and the dielectric loss decreased from 2.36 to 1.28 when Co content increased from 0 to 10 atom %.

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