共查询到20条相似文献,搜索用时 31 毫秒
1.
E. Sillero F. Calle M. A. Sánchez-García 《Journal of Materials Science: Materials in Electronics》2005,16(7):409-413
Reactive ion etching with SiCl4:Ar:SF6 mixtures of gallium nitride epitaxial layers grown by metal organic chemical vapour deposition (MOCVD) has been studied. The effects of several factors such as gas mixture, chamber pressure, and drive power on the etch rate and etched profile have been investigated. A strong dependence of both properties with the amount of SF6 present in the mixture has been found. High etch rates (> 50 nm/min) and controllable sidewall angles and smoothness have been achieved. 相似文献
2.
The plasma assisted etching of SiO2 in a commercial RF reactor with a variety of C4F8/Ar/O2 chemistries has been studied by XPS, SIMS and FTIR. A simple model of surface reactions is proposed. In particular, the role of oxygen in the etch process has been investigated. According to our experiments, oxygen inhibits the formation of CFH based polymeric films on the surface. As the etching process is due to an exchange reaction between the oxygen in the SiO2 and the gaseous fluorine species in the plasma, the presence of oxygen in the etch hinders this process by occupying adsorption sites on the surface. The results would confirm that argon does not participate in chemical reactions with the SiO2 substrate but provides energy for reactions in which F, C and O are involved. The results also indicate that a thick fluorocarbon layer only forms on the surface in the absence of oxygen, regardless of the oxygen source. Consequently, only when the SiO2 layer has been substantially removed does this film form. 相似文献
3.
Qian Jiang Weiyan Wang Yuheng Zeng Wei Xu Jinhua Huang Ti Zhou Weijie Song 《Journal of Materials Science: Materials in Electronics》2014,25(12):5356-5361
In this work, aluminum-doped zinc oxide (AZO)/p-Si heterojunction solar cells were prepared by sputtering of ~120 nm AZO thin films in Ar or Ar–H2 atmosphere on textured p-Si wafers, and the effects of hydrogen incorporation on the solar cell performance were investigated. Results showed that the performance of AZO/p-Si heterojunction solar cells was improved with the increase of hydrogen volume concentration from 0 to 23 %. The AZO:H/p-Si heterojunction solar cells prepared in Ar–23 % H2 exhibited a short-circuit current density of 29 mA/cm2 and a conversion efficiency of 2.84 %. The reflectance measurement indicated that the reflectance of p-Si surface in the range of 400–1,100 nm decreased from 13 to 4 % after AZO:H films coating; and the capacitance–voltage measurement indicated that the density of defect states at AZO/p-Si interface was decreased after hydrogen incorporation. Passivation and antireflection functions can be realized in AZO:H films deposited in Ar–H2, which opens a novel route to prepare cost-effective AZO/p-Si heterojunction solar cells. 相似文献
4.
Arti Gupta Shankar Dutta R. P. Tandon 《Journal of Materials Science: Materials in Electronics》2018,29(4):2764-2770
This paper reports growth of Co0.6Zn0.4Mn0.3Fe1.7O4 (CZFMO) ultrathin films (thickness: 23–30 nm) by spin coating technique on silicon (100), (110) and (111) substrates. The deposited films were annealed at 700 °C for 1 h in the oxygen environment. All the films were found to be polycrystalline in nature. The CZFMO films were found to have minimal residual stress (13–50 MPa), which could be an encouraging feature for novel microwave miniaturized device applications. Room temperature magnetic measurements demonstrated completely saturated hysteresis loop with the highest squareness ratio (M R /M S )?~?60% for the film grown on Si (110) substrate. On the other hand CZFMO films on Si (100) and Si (111) substrates showed unsaturated hysteresis loops with M R /M S ~ 10 and 5%, respectively. The reason for the better magnetic properties of the ultrathin CZFMO film on Si (110) substrate seems to be its better crystalline quality and larger grain size compared to those of other films. 相似文献
5.
C. R. Foschini R. Tararam A. Z. Simões L. S. Rocha C. O. P. Santos E. Longo J. A. Varela 《Journal of Materials Science: Materials in Electronics》2016,27(3):2175-2182
Calcium copper titanate, CaCu3Ti4O12, CCTO, thin films with polycrystalline nature have been deposited by RF sputtering on Pt/Ti/SiO2/Si (100) substrates at a room temperature followed by annealing at 600 °C for 2 h in a conventional furnace. The crystalline structure and the surface morphology of the films were markedly affected by the growth conditions. Rietveld analysis reveal a CCTO film with 100 % pure perovskite belonging to a space group Im3 and pseudo-cubic structure. The XPS spectroscopy reveal that the in a reducing N2 atmosphere a lower Cu/Ca and Ti/Ca ratio were detected, while the O2 treatment led to an excess of Cu, due to Cu segregation of the surface forming copper oxide crystals. The film present frequency -independent dielectric properties in the temperature range evaluated, which is similar to those properties obtained in single-crystal or epitaxial thin films. The room temperature dielectric constant of the 600-nm-thick CCTO films annealed at 600 °C at 1 kHz was found to be 70. The leakage current of the MFS capacitor structure was governed by the Schottky barrier conduction mechanism and the leakage current density was lower than 10?7 A/cm2 at a 1.0 V. The current–voltage measurements on MFS capacitors established good switching characteristics. 相似文献
6.
Feng Chen Jinrong Cheng Shenwen Yu Zhongyan Meng 《Journal of Materials Science: Materials in Electronics》2010,21(5):514-518
Pb(Zr0.53Ti0.47)O3 (PZT) thin films were prepared on La0.5Sr0.5CoO3 (LSCO) coated Si substrates by a sol–gel route. The thickness of LSCO electrode was found to modify the preferential orientation
of PZT thin films, which consequently affected the dielectric and ferroelectric properties. (100) textured PZT films with
dense columnar structure could be obtained on the top of (110) textured LSCO with thickness of 230 nm. PZT thin films prepared
on the optimized LSCO films exhibit the enhanced dielectric constant and remnant polarization of 980 and 20 μC/cm2, respectively. 相似文献
7.
Yaguang Wang Jianmin Li Cong Xue Yan Zhang Guoshun Jiang Weifeng Liu Changfei Zhu 《Journal of Materials Science》2017,52(11):6225-6234
In this paper, Cu2SnS3 (CTS) thin film is fabricated through sulfurization of oxide precursor which is deposited by pulsed laser deposition with a mixed CuO/SnO2 target. XRD and Raman analyses indicate a pure monoclinic Cu2SnS3 phase has been obtained by sulfurization at temperature from 500 to 600 °C. A compact and smooth film with polycrystalline structure is observed through SEM result. In addition, the CTS films show excellent absorbance with the band gap around 0.91 eV estimated by UV–Vis, which is suitable for the absorption layer of solar cells. Final devices were fabricated with a SLG/Mo/CTS/CdS/i-ZnO/AZO/Al structure. Device performance is improved with the temperature increasing. The best efficiency of CTS-based solar cells is 0.69% with an open-circuit voltage of 144 mV and a short-circuit current density of 18.30 mA/cm?2. 相似文献
8.
N. Usha R. Sivakumar C. Sanjeeviraja R. Balasubramaniam Y. Kuroki 《Journal of Materials Science: Materials in Electronics》2016,27(8):7809-7821
Nb2O5:MoO3 (95:5 and 85:15) thin films were deposited onto glass and fluorine doped tin oxide coated glass substrates at 100 and 300 °C by RF magnetron sputtering technique. The physical and electrochromic properties of the films were studied. XRD result reveals that deposited films were amorphous. The XPS study confirms the compositional purity and the presence of Nb5+ and Mo6+ in the deposited film. Surface morphological study shows platelet like features of deposited film. The average transmittance of the film is varied between 91 and 85 %. Photoluminescence study exhibits three characteristic emission peaks and confirms the better optical quality of deposited film. Raman spectra show the LO–TO splitting of Nb–O stretching of the deposited film. Electrochromic behavior of the deposited films characterized by cyclic voltammetry using 0.5 M LiClO4·PC and 0.5 M H2SO4 electrolyte solutions show all the films are having better reversibility and reproducibility in their electrochemical analysis. 相似文献
9.
M. Kraini N. Bouguila N. Moutia J. El Ghoul K. Khirouni C. Vázquez-Vázquez 《Journal of Materials Science: Materials in Electronics》2018,29(3):1888-1906
In this work, nickel (Ni) doped indium sulfide (In2S3) films have been prepared by the spray pyrolysis (CSP) technique on glass substrates at 350 °C. The Ni doping level was changed with Ni:In (0, 2 and 4% in solution). The structural studies reveal that the deposited films are polycrystalline in nature exhibiting cubic structure. The crystallite size decreases from 27.5 to 23 nm and the root mean square roughness values increase from 13 to 18 nm. The transmission coefficient is about 70–55% in the visible region and 85–75% in near-infrared region. The band gap energy increases with nickel content from 2.74 to 2.82 eV for direct transitions. The refractive index values of In2S3:Ni thin films decrease from 2.43 to 2.40 and the extinction coefficient values are in the range 0.01–0.20. Besides, the AC conductivity contribution is interpreted using the universal Jonscher’s power law and it is found thermally activated and it can be described by the correlated barrier-hopping models. These studies help to form significant correlation between temperature and activation energy. Nyquist plots show that the electrical response is accurately fitted by the Cole–Cole model and represented by an equivalent electrical circuit which consists of a parallel combination of a resistance and a constant phase element. From this analysis, the evidence of grain boundary conduction has been observed. 相似文献
10.
R. S. Ingole S. B. Kondawar B. J. Lokhande 《Journal of Materials Science: Materials in Electronics》2017,28(3):2385-2391
A scheme of substrate dependent self-organization of vanadium oxide has been used to create unique supercapacitor electrodes. In present work, thin films of V2O5 were prepared on different substrates by using well known spray pyrolysis technique.The sample depositions were carried out at 673 K, by spraying 0.05 M, 40 ml solution of ammonium metavanadate at the spray rate 10 ml/min. V2O5 thin films grown on aluminum (Al), copper (Cu) and stainless steel (SS) substrates shows porous valley and mountains, rough and dense morphology with overgrown agglomeration of nano grains. In electrochemical characterizations, by using standard electrode configurations, specific capacitance values were evaluated from cyclic voltammetry in 1 M KCl, these are 18.43, 1500.0, 439.60 and 250.58 F/g at 5 mV/s for the electrodes deposited on Al, Cu, SS substrates and two electrode cell respectively. Charge discharge behavior of the SS electrode and two electrode cell was observed using chronopotentiometry. This exhibits specific energy, specific power, and coulombic efficiency (η) 84.91 Wh/kg, 120.00 kW/kg and 89.51 % for SS electrode and 19.92 Wh/kg, 65.00 kW/kg and 99.90 % for two electrode cell respectively. Impedance study was carried out in the frequency range 1 mHz–1 MHz depicts less internal resistance of SS electrode ~2.69 Ω and two electrode cell ~3.04 Ω. 相似文献
11.
Do Young Lee 《Thin solid films》2009,517(14):4047-4051
Inductively coupled plasma reactive ion etching of indium zinc oxide (IZO) thin films masked with a photoresist was performed using a Cl2/Ar gas. The etch rate of the IZO thin films increased as Cl2 gas was added to Ar gas, reaching a maximum at 60% Cl2 and decreasing thereafter. The degree of anisotropy in the etch profile improved with increasing coil rf power and dc-bias voltage. Changes in pressure had little effect on the etch profile. X-ray photoelectron spectroscopy confirmed the formation of InCl3 and ZnCl2 on the etched surface. The surface morphology of the films etched at high Cl2 concentrations was smoother than that of the films etched at low Cl2 concentrations. These results suggest that the dry etching of IZO thin films in a Cl2/Ar gas occurs according to a reactive ion etching mechanism involving ion sputtering and a surface reaction. 相似文献
12.
Wanlin Zhu Wei Luo Betul Akkopru-Akgun Michael Lanagan Clive A. Randall Susan Trolier-McKinstry 《Journal of Materials Science》2018,53(10):7180-7186
This paper discusses the advantages of a room-temperature poling procedure during exposure to ultraviolet light for Pb(Zr0.52Ti0.48)O3 (PZT) films. The results of these experiments include the following: for 1.7-µm-thick chemical solution-deposited PZT films, the saturation photocurrent density after a 10 min white light exposure (190–1900 nm) (no DC bias field applied) increased up to 0.066 µA/cm2 with increasing Cr thickness of top electrode in Cr/Pt bilayer electrodes. Furthermore, the d33,f piezoelectric coefficients for UV-poled samples were 40 and 20% higher than those achieved from field-only poling at either room temperature or 150 °C. Additionally, the development of an internal bias field and pinching were investigated in major and minor polarization–electric field loops. It was found that ultraviolet illumination during the poling process produced photoinduced charge carriers that became trapped by local defects and/or grain boundaries in the films. 相似文献
13.
The plasma produced by the mixture of fluoride and argon (SF6/Ar) was applied for the dry etching of AlN films. Very high etching rate up to 140 nm/min have been observed. The effects of the bias voltage and the plasma component on the etching results were investigated. It shows that AlN can be effectively etched by the plasma with the moderate SF6 concentration and the etching rate varies linearly with the bias voltage. The FTIR spectra confirm that AlF3 is formed due to the chemical reaction of Al and F atoms. The mechanism of AlN etching in F-based plasma is probably a combination between physical sputtering and chemical etching and can be briefly outlined: (i) F− ions reacts with Al atoms to form low volatile product AlF3 and passivate the surface, and (ii) at the same time the Ar+ ions sputter the reaction product from the surface and keep it fluoride free to initiate further reaction. AlF3 formed on the patterned sidewall play a passivation role during the etching process. The etching process is highly anisotropic with quite smooth surface and vertical sidewalls. 相似文献
14.
A. I. Stognij N. N. Novitskii O. L. Golikova A. V. Bespalov R. Gieniusz A. Maziewski A. Stupakiewicz M. N. Smirnova V. A. Ketsko 《Inorganic Materials》2017,53(10):1069-1074
Amorphous yttrium iron garnet films ranging in thickness from 100 to 600 nm have been produced on single-crystal silicon substrates by sputtering a polycrystalline target with the composition Y3Fe5O12 (yttrium iron garnet) by a mixture of argon and oxygen ions. Before film growth, AlO x or SiO2 buffer layers up to 0.8 μm in thickness were grown on the Si surface. The heterostructures were crystallized by annealing in air at a temperature of 950°C for 30 min. The properties of the films were studied by magneto-optical techniques, using Kerr effect and ferromagnetic resonance measurements. The Gilbert damping parameter reached 2.8 × 10–3 and the effective planar magnetic anisotropy field was independent of the nature of the buffer layer. This suggests that the thin-film heterostructures obtained in this study are potentially attractive for use in spin-wave semiconductor devices. 相似文献
15.
Zhonghua Deng Changgang Huang Jiquan Huang Meili Wang Hong He Hai Wang Yongge Cao 《Journal of Materials Science: Materials in Electronics》2010,21(10):1030-1035
Aluminum doped zinc oxide (AZO) films were deposited on quartz substrates by radio-frequency magnetron co-sputtering method
with ZnO and Al2O3 ceramic targets. The structural, optical and electrical properties of these films as a function of the Al content were investigated.
XRD results reveal that the AZO films are wurtzite structure with (002) preferred orientation. The average transmittance of
all the films is higher than 80% in a wide wavelength range from 400 to 1,500 nm. The band gap energy, calculated from their
optical absorption spectra, is in the range of 3.50–3.66 eV depending on the Al content. Doping of Al3+ in the ZnO makes the film surface roughness decrease. The dopant Al3+ acts as electron donor by which the electrical conductivity and carrier concentration of the films are obviously increased
until the Al3+ reaches its saturation content of about 4.50 at.%. 相似文献
16.
Zhenxun Ming Chao Ding Bing Li Lianghuan Feng Judy Wu 《Journal of Materials Science: Materials in Electronics》2014,25(4):1901-1907
Cadmium telluride (CdTe) thin films deposited by pulsed laser deposition (PLD) on fluorine–tin–oxide substrates under different pressures of argon (Ar) + oxygen (O2) at high substrate temperature (Ts = 500 °C) was reported in this paper. In our work, the CdTe thin films were prepared successfully at high Ts by inputting Ar + O2. As reported, PLD-CdTe thin films were almost prepared at low substrate temperatures (<300 °C) under vacuum conditions. The deposition of CdTe thin films at high Ts by PLD is rarely reported. The influence of the Ar + O2 gas pressure on thickness, structural performance, surface morphology, optical property and band gap (Eg) had been investigated respectively by Ambios probe level meter, X-ray diffraction (XRD), scanning electron microscopy (SEM) and UV–Vis spectrometer. Strong dependence of properties on the deposition pressures was revealed. In the range of Ar + O2 gas pressure from 5 to 12 Torr, the deposition rate and the Eg of CdTe films vary in the range of 41.9–57.66 nm/min then to 35.26 nm/min and 1.51–1.54 eV then to 1.47 eV, respectively. The XRD diagrams showed that the as-deposited films were polycrystalline, and the main phase was cubic phase. However, the preferred orientation peak disappeared when the deposition pressure was higher. SEM images indicated that the CdTe film deposited at a higher deposition pressure was more uniform and had a higher compactness and a lower pinhole density. Furthermore, based on this thorough study, FTO/PLD-CdS (100 nm)/PLD-CdTe (~1.5 μm)/HgTe:Cu/Ag solar cells with an efficiency of 6.68 % and an area of 0.64 mm2 were prepared successfully. 相似文献
17.
M. C. Cordero-Cabrera T. Mouganie B. A. Glowacki M. Bäcker M. Falter B. Holzapfel J. Engell 《Journal of Materials Science》2007,42(17):7129-7134
The objective of this paper is to prove the possibility to produce single side buffered substrates for coated conductors.
We report for the first time the production of highly textured NiW/La2Zr2O7/CeO2 system by all-chemical solution deposition means using an in-house built drop-on-demand ink-jet printer. Lanthanum zirconate
precursor ink was produced using lanthanum acetate and zirconium n-propoxide modified with propionic and acetic acid, respectively,
and diluted with methanol. Cerium oxide precursor ink was prepared using cerium acetylacetonate dissolved in acetylacetone
and diluted in methanol. Optimized ink jet control parameters (inter-droplet distance, nozzle opening time and pressure in
the chamber) allowed the deposition of homogeneous highly textured films with a thickness of approximately 150–200 nm at speeds
as high as 27 cm/min. La2Zr2O7 film showed in plane and out of plane misalignment of 6.6° and 7.4°, respectively, whereas values obtained for CeO2 were 7.8° and 8.1°, respectively. This study represents a step forward in the production of reel-to-reel coated conductors
in an efficient and economic way. 相似文献
18.
Mohammed K. Al-hashimi Burak Y. Kadem Aseel K. Hassan 《Journal of Materials Science: Materials in Electronics》2018,29(9):7152-7160
Titanium dioxide (TiO2) thin films were prepared by sol–gel spin coating method and deposited on ITO-coated glass substrates. The effects of different heat treatment annealing temperatures on the phase composition of TiO2 films and its effect on the optical band gap, morphological, structural as well as using these layers in P3HT:PCBM-based organic solar cell were examined. The results show the presence of rutile phases in the TiO2 films which were heat-treated for 2 h at different temperatures (200, 300, 400, 500 and 600 °C). The optical properties of the TiO2 films have altered by temperature with a slight decrease in the transmittance intensity in the visible region with increasing the temperature. The optical band gap values were found to be in the range of 3.28–3.59 eV for the forbidden direct electronic transition and 3.40–3.79 eV for the allowed direct transition. TiO2 layers were used as electron transport layer in inverted organic solar cells and resulted in a power conversion efficiency of 1.59% with short circuit current density of 6.64 mA cm?2 for TiO2 layer heat-treated at 600 °C. 相似文献
19.
Heavily doped metal oxide semiconductors are being developed as thin film transparent electrodes for many applications and their deposition at low substrate temperature can extend the use on heat sensitive devices. The structural and electro-optical characteristics of such metal oxide coatings are tightly related and depend on the specific deposition parameters apart from the material composition. In this work, SnO2:Sb (ATO) and ZnO:Al (AZO) thin films have been prepared by sputtering at room temperature on glass substrates, changing the deposition time to obtain various layer thicknesses from 0.2 to 0.9 μm; and they have been analyzed by X-ray diffraction, spectrophotometry, and Hall-effect measurements. ATO samples crystallize in the tetragonal structure with mean crystallite size increasing from 8 to 20 nm when the film thickness grows. The comparison of Hall mobility and optical mobility values indicates a significant contribution of grain boundary scattering for these ATO layers. Otherwise, AZO films show larger crystallites (21–27 nm) and a strong preferential orientation for analogous thickness increment, resulting in a lower contribution of the grain boundary scattering to the overall Hall mobility. The in-grain mobility for each sample is also related to the respective crystallite size and carrier concentration values. 相似文献
20.
Nb2O5 films have been deposited on variety of substrates using the sol-gel dip coating technique. As-deposited films on all substrates are amorphous. Films were annealed under controlled ambience at 300, 400 and 600°C for 5 h. As-deposited films on glass substrate show uniform surface structure. The crystal structure and surface topography are found to depend strongly on the annealing temperature and nature of the substrates. The average grain size of 40 nm is observed in films annealed at 300°C. On annealing at 400°C increasing grain size and resulting fusing of them, enhanced surface roughness. Films deposited on NaCl substrates crystallized into a stable monoclinic phase and those deposited on single crystal Si substrates crystallized into hexagonal phase after annealing at 600°C. The as-deposited films show very high transmittance (>90%) in the visible region. The optical band gap is observed to increase from 4.35 eV when the films are in amorphous state to 4.87 eV on crystallization. 相似文献