共查询到20条相似文献,搜索用时 31 毫秒
1.
Emma Cárdenas E. Perez-Tijerina T.K. Das Roy B. Krishnan 《Solar Energy Materials & Solar Cells》2009,93(1):33-36
We report the modification of electrical properties of chemical-bath-deposited antimony sulphide (Sb2S3) thin films by thermal diffusion of carbon. Sb2S3 thin films were obtained from a chemical bath containing SbCl3 and Na2S2O3 salts at room temperature (27 °C) on glass substrates. A carbon thin film was deposited on Sb2S3 film by arc vacuum evaporation and the Sb2S3-C layer was subjected to heating at 300 °C in nitrogen atmosphere or in low vacuum for 30 min. The value of resistivity of Sb2S3 thin films was substantially reduced from 108 Ω cm for undoped condition to 102 Ω cm for doped thin films. The doped films, Sb2S3:C, retained the orthogonal stibnite structure and the optical band gap energy in comparison with that of undoped Sb2S3 thin films. By varying the carbon content (wt%) the electrical resistivity of Sb2S3 can be controlled in order to make it suitable for various opto-electronic applications. 相似文献
2.
Sin Kyu Kim 《Solar Energy Materials & Solar Cells》2008,92(11):1311-1314
Copper gallium disulfide (CuGaS2; CGS) films were deposited on glass or ITO glass by two-stage metal-organic chemical vapor deposition (MOCVD) method, using Cu- and Ga/S-containing precursors without toxic H2S gas. First, pure Cu thin films were prepared on glass substrates by using a single-source precursor, bis(ethylbutyrylacetato)copper(II) or bis(ethylisobutyrylacetato)copper(II). Second, the resulting Cu films were processed using tris(N,N-ethylbutyldithiocarbamato)gallium(III) at 410-470 °C to produce CuGaS2 films. The optical band gap of the CGS film grown at 440 °C was about 2.53 eV. In addition, it was found that the elemental ratio of Cu and Ga elements of the CGS films can be elaborately adjusted by controlling deposition conditions on demand. 相似文献
3.
Studies on Cu2ZnSnS4 (CZTS) absorber layer using different stacking orders in precursor thin films 总被引:1,自引:0,他引:1
Seung Wook ShinS.M. Pawar Chan Young ParkJae Ho Yun Jong-Ha MoonJin Hyeok Kim Jeong Yong Lee 《Solar Energy Materials & Solar Cells》2011,95(12):3202-3206
Cu2ZnSnS4 (CZTS) thin films were deposited by sputtering on glass substrates using stacked precursors. The stacked precursor thin films were prepared from Cu, SnS2 and ZnS targets at room temperature with different stacking orders of Cu/SnS2/ZnS/glass (A), ZnS/Cu/SnS2/glass (B) and SnS2/ZnS/Cu/glass (C). The stacked precursor thin films were sulfurized using a tubular rapid thermal annealing system in a mixed N2 (95%)+H2S (5%) atmosphere at 550 °C for 10 min. The effects of the stacking order in the precursor thin films on the structural, morphological, chemical, electrical and optical properties of the CZTS thin films were investigated. X-ray diffraction, Raman spectroscopy and X-ray photoelectron spectroscopy studies showed that the annealed CZTS thin film using a stacking order A had a single kesterite crystal structure without secondary phases, whereas stacking orders B and C have a kesterite phase with secondary phases, such as Cu2−xS, SnS2 and SnS. The annealed CZTS thin film using stacking order A showed a very dense morphology without voids. On the other hand, the annealed CZTS thin films using stacking orders B and C contained the volcano shape voids (B) and Sn-based secondary phases (C) on the surface of the annealed thin films. The direct band gap energies of the CZTS thin films were approximately 1.45 eV (A), 1.35 eV (B) and 1.1 eV (C). 相似文献
4.
Lin Sun Jun HeHui Kong Fangyu YuePingxiong Yang Junhao Chu 《Solar Energy Materials & Solar Cells》2011,95(10):2907-2913
Polycrystalline Cu2ZnSnS4 (CZTS) thin films have been directly deposited on heating Mo-coated glass substrates by Pulsed Laser Deposition (PLD) method. The results of energy dispersive X-ray spectroscopy (EDX) indicate that these CZTS thin films are Cu-rich and S-poor. The combination of X-ray diffraction (XRD) results and Raman spectroscopy reveals that these thin films exhibit strong preferential orientation of grains along [1 1 2] direction and small Cu2−xS phase easily exists in CZTS thin films. The lattice parameters and grain sizes have been examined based on XRD patterns and Atom Force Microscopy (AFM). The band gap (Eg) of CZTS thin films, which are determined by reflection spectroscopy varies from 1.53 to 1.98 eV, depending on substrate temperature (Tsub). The optical absorption coefficient of CZTS thin film (Tsub=450 °C) measured by spectroscopic ellipsometry (SE) is above 104 cm−1. 相似文献
5.
Yanfeng CuiShaohua Zuo Jinchun Jiang Shengzhao YuanJunhao Chu 《Solar Energy Materials & Solar Cells》2011,95(8):2136-2140
Cu2ZnSnS4 thin films have been successfully prepared by a novel synthesis process that involves a single step deposition of Cu2ZnSnS4 followed by a post-annealing treatment at 550 °C for 60 min in the atmosphere of N2+H2S (5%). The microstructure, morphology, composition and optical property of the film have been investigated in detail. It is found that the Na2S2O35H2O concentration in the solution has a significant effect on the Cu2ZnSnS4 thin films. X-ray diffraction data indicates that the annealed Cu2ZnSnS4 thin films have a kesterite structure with preferred orientation along the (1 1 2) plane. Uniform and compact topographies are observed in some annealed films. From the energy dispersive X-ray spectroscopy analysis, it can be seen that Cu-poor and Zn-rich Cu2ZnSnS4 thin films have been obtained. The direct band gap energy of the film is about 1.5 eV. 相似文献
6.
Zainovia Lockman Loh Poh Lin Cheong Kuan Yew Sabar Derita Hutagalung 《Solar Energy Materials & Solar Cells》2009,93(8):1383-1387
An 850-nm-thick CuAlO2 film was formed by solid state reaction of evaporated thin film Cu on c-cut Al2O3 (sapphire) at 1200 °C for reaction times as short as 10 min. X-ray diffractogram confirms the formation of (0 0 l) CuAlO2, indicating oriented growth of CuAlO2 on c-cut Al2O3. Fourier transformation infra-red (FTIR) spectra showed peaks corresponding to Cu-O, Al-O and O-Cu-O bonds, confirming further the CuAlO2 phase formation. UV-visible spectrum measurement showed high transparency of the film in the visible region with a direct band gap of 3.25 eV. The mechanism of the formation of the film is discussed. 相似文献
7.
CuInSe2 thin films were prepared using sequential vacuum evaporation of In, Se and Cu at moderately low substrate temperatures, avoiding any treatment using toxic H2Se gas. The samples were annealed at 400 °C at a pressure of 10−5 mbar to form CuInSe2. Structural, optical, electrical, compositional and morphological characterizations were carried out on these films. We could obtain highly stoichiometric film, using this simple method, without opting for co-evaporation or high substrate temperature for deposition. 相似文献
8.
R.B.V. ChalapathyGwang Sun Jung Byung Tae Ahn 《Solar Energy Materials & Solar Cells》2011,95(12):3216-3221
Cu2ZnSnS4 (CZTS) absorbers were grown by sulfurization of Cu/ZnSn/Cu precursors in sulfur atmosphere. The reaction mechanism of CZTS formation from the precursor was analyzed using XRD and Raman spectroscopy. The films with a single phase CZTS were formed at 560 and 580 °C by sulfurization for 30 min. The film grown at 560 °C showed bi-layer morphology with grooved large grains on the top and dense small grains near the bottom of the film. On the other hand, the film grown at 580 °C showed large grains with grooves that are extended from surface top to bottom of the film. The solar cell fabricated with the CZTS film grown at 560 °C showed the best conversion efficiency of 4.59% for 0.44 cm2 with Voc=0.545 V, Jsc=15.44 mA/cm2, and FF=54.6. We found that further improvement of the microstructure of CZTS films can increase the efficiency of CZTS solar cells. 相似文献
9.
K. Rajasekar A. Subbarayan R. Sathyamoorthy 《Solar Energy Materials & Solar Cells》2006,90(15):2515-2522
Thin films of (Sb2Te3)70 (Bi2Te3)30 were prepared by thermal evaporation. The composition of the film was confirmed by energy dispersive analysis (EDAX). X-ray diffraction studies showed that the film was polycrystalline with grain size of 4.39 Å and with a preferred orientation in the (0 1 5) directions. Al/((Sb2Te3)70 (Bi2Te3)30)/Al (MSM) thin film capacitors are formed and its AC and dielectric studies were carried out using a digital LCR metre at various frequencies (12 Hz–100 kHz) and temperatures (303–483 K). The dielectric constant for a film of thickness 3000 Å was found to be 86 for 1 kHz at room temperature. The temperature coefficient of capacitance (TCC) and temperature coefficient of permittivity (TCP) were estimated as 684 and 1409 ppm/K for 10 kHz at 303 K, respectively. The activation energy was estimated as 1.190 eV for frequency of 100 kHz at 303 K. The AC conductivity of the films was found to be a hopping mechanism. 相似文献
10.
X.H. Xu F. Wang J.J. Liu K.C. ParkM. Fujishige 《Solar Energy Materials & Solar Cells》2011,95(2):791-796
Copper indium disulfide (CuInS2) thin films have been successfully prepared on Ni substrates using a novel one-step potentiostatic electrodeposition combined with a potassium hydrogen phthalate (C8H5KO4) complexing agent, accompanied by annealing at 350 °C. Electrodeposition in the solution of Cu and In salts and sodium thiosulfate (Na2S2O3) containing an adequate concentration of C8H5KO4 (e.g., [C8H5KO4]=23 mM) provides thin films comprised of a CuInS2 single phase as the bulk composition, without forming CuxS secondary phases. In addition to the effect on bulk-phase compositions, the adjustment of [C8H5KO4] causes variation in morphology and atomic composition of the film surface. The surface states of the films change from the Cu-rich rough surface at low [C8H5KO4] (15 mM) to the In-rich smooth surface at high [C8H5KO4] (23 mM). The higher [C8H5KO4] induces the grains constructing the film to interconnect and form a densely packed CuInS2 film without voids and pinholes. The single-phase and void-free CuInS2 film shows a band gap of 1.54 eV, satisfying the requirement of the absorber layers in solar cells. The electrical properties tests denote its n-type conductivity with a resistivity of 9.6×10−5 Ω cm, a carrier concentration of 2.9×1021 cm−3 and a carrier mobility of 22.2 cm2 V−1 s−1. 相似文献
11.
Electrical and optical properties of Cu2ZnSnS4 thin films prepared by rf magnetron sputtering process 总被引:2,自引:0,他引:2
Jae-Seung Seol Sang-Yul Lee Jae-Choon Lee Hyo-Duk Nam Kyoo-Ho Kim 《Solar Energy Materials & Solar Cells》2003,75(1-2):155-162
Cu2ZnSnS4 thin films were deposited on corning 7059 glass substrates without substrates heating by rf magnetron sputtering. The Cu/(Zn+Sn) ratio of the thin film sputtered at 75 W was close to the stoichiometry of Cu2ZnSnS4. However, the S/(Cu+Zn+Sn) ratio was less than the stoichiometry. The as-deposited films were amorphous and annealed in the atmosphere of Ar+S2 (g). The annealed (1 1 2), (2 0 0), (2 2 0), (3 1 2) planes were conformed to all the reflection of a kesterite structure. A preferred (1 1 2) orientation was observed with the increase of the annealing temperature. The optical absorption coefficient of the thin film was about 1.0×104 cm−1. The optical band energy was derived to be 1.51 eV. The optical absorption coefficient of the sputtered Cu2ZnSnS4 thin films was less than that of CuInS2 thin film, however, the band gap energy was more appropriate for photovoltaic materials. 相似文献
12.
Kazuya MaedaKunihiko Tanaka Yuki FukuiHisao Uchiki 《Solar Energy Materials & Solar Cells》2011,95(10):2855-2860
Cu2ZnSnS4 (CZTS) thin films prepared by a non-vacuum process based on the sulfurization of precursor coatings, consisting of a sol-gel solution of Cu, Zn, and Sn, under H2S+N2 atmosphere were investigated. The structure, microstructure, and electronic properties of the CZTS thin films as well as solar cell parameters were studied in dependence on the H2S concentration. The sulfurization process was carried out at 500 °C for 1 h in an H2S+N2 mixed-gas atmosphere with H2S concentrations of 3%, 5%, 10%, and 20%. As the H2S concentration decreased from 20% to 5%, the S content of the CZTS thin films decreased. However, when the H2S concentration was decreased below 3%, the S content of the films began to increase. A CZTS thin film prepared with an H2S concentration of 3% had grains in the order of 1 μm in size, which were larger than those of films prepared at other H2S concentrations. Furthermore, the most efficient solar cell, with a conversion efficiency of 2.23%, was obtained from a sample sulfurized at an H2S concentration of 3%. 相似文献
13.
K. Bindu C. Sudha Kartha K. P. Vijayakumar T. Abe Y. Kashiwaba 《Solar Energy Materials & Solar Cells》2003,79(1):3107
Copper indium selenide thin films were prepared through a novel and an eco-friendly selenisation process. In this method, selenium film required for selenisation was prepared using chemical bath deposition technique, at room temperature. Thus, totally avoided usage of highly toxic H2Se or selenium vapour. Here, the process involved annealing the Stacked layer, Se/In/Cu in which Cu and In were deposited using vacuum evaporation technique. Investigations on the solid-state reaction between the layers were done by analysing structural and optical properties of films formed at different annealing temperatures. Optimum annealing condition for the formation of copper indium selenide thin film was found to be 673 K for 1 h in high vacuum. Compositional dependence of the growth process was also studied using various Cu/In ratios. Optical band gap was decreased with increase in Cu/In ratio. Carrier concentration and hence conductivity were found to be increased with increase in Cu/In ratio. The films obtained were p-type and highly Cu-rich films were degenerate. 相似文献
14.
β-In2S3 films were grown on glass as well as on quartz substrates by rapid heating of metallic indium films in H2S atmosphere. The effect of sulfurization temperature and time on the growth, structural, electrical and photoelectrical properties of β-In2S3 films has been investigated. Highly oriented single-phase β-In2S3 films were grown by the sulfurization technique. The morphology and composition of films have been characterized. The optical band gap of β-In2S3 is found to vary from 1.9 to 2.5 eV when the sulfurization temperature is varied from 300 to 600 °C or by increasing the sulfurization time. The electrical properties of the thin films have also been studied; they have n-type electrical conductivity. The photoelectrical properties of the β-In2S3 films are also found to depend on the sulfurizing temperature. A high photoresponse is obtained for films prepared at a sulfurizing temperature of 600 °C. β-In2S3 can be used as an alternative to toxic CdS as a window layer in photovoltaic technology. 相似文献
15.
Optimization of substrate temperature of spray pyrolysed CuInS2 absorber is discussed along with its effect on the photoactivity of junction fabricated. For CuInS2 thin films, properties like crystallinity, thickness and composition showed progressive behavior with substrate temperature. X-ray photoelectron spectroscopic depth profile of all the samples showed that the concentration of copper on the surface of the films is significantly lesser than that in the bulk thus avoiding need for toxic cyanide etching. Interestingly, samples prepared at 623 K had higher conductivity compared to those prepared above and below this temperature. Also, the low energy transition, in addition to the direct band gap which was observed in other samples were absent in films prepared at 623 K. From thermally stimulated conductivity studies it was seen that shallow levels present in this sample contribute to its improved conductivity. Also, CuInS2/In2S3 bilayer prepared at this substrate temperature showed higher photoactivity than those prepared at other temperatures. 相似文献
16.
Porous Co3O4 nanostructured thin films are electrodeposited by controlling the concentration of Co(NO3)2 aqueous solution on nickel sheets, and then sintered at 300 °C for 3 h. The as-prepared thin films are characterized by thermogravimetric analysis (TGA), X-ray diffraction (XRD), and scanning electron microscopy (SEM). The electrochemical measurements show that the highly porous Co3O4 thin film with the highest electrochemically active specific surface area (68.64 m2 g−1) yields the best electrochemical performance compared with another, less-porous film and with a non-porous film. The highest specific capacity (513 mAh g−1 after 50 cycles) is obtained from the thinnest film with Co3O4 loaded at rate of 0.05 mg cm−2. The present research demonstrates that electrode morphology is one of the crucial factors that affect the electrochemical properties of electrodes. 相似文献
17.
Nanostructured TiO2 thin films were deposited on glass substrates by sol-gel dip coating technique. The structural, morphological and optical characterizations of the as deposited and annealed films were carried out using X-ray diffraction (XRD), Raman spectroscopy, atomic force microscopy (AFM), and UV-vis transmittance spectroscopy. As-deposited films were amorphous, and the XRD studies showed that the formation of anatase phase was initiated at annealing temperature close to 400 °C. The grain size of the film annealed at 600 °C was about 20 nm. The lattice parameters for the films annealed at 600 °C were a = 3.7862 ? and c = 9.5172 ?, which is close to the reported values of anatase phase. Band gap of the as deposited film was estimated as 3.42 eV and was found to decrease with the annealing temperature. At 550 nm the refractive index of the films annealed at 600 °C was 2.11, which is low compared to a pore free anatase TiO2. The room temperature electrical resistivity in the dark was of the order of 4.45 × 106 ohm-cm. Photocatalytic activity of the TiO2 films were studied by monitoring the degradation of aqueous methylene blue under UV light irradiation and was observed that films annealed above 400 °C had good photocatalytic activity which is explained as due to the structural and morphological properties of the films. 相似文献
18.
The CuInTe2 thin films were prepared by thermal vacuum evaporation from a single source. The effects of heat treatment on both structural an optical properties of CuInTe2 films were studied. X-ray diffraction studies reveal that the films prepared by the present method showed formation of single phase CuInTe2 at heating treatment temperature higher than 300°C. The calculated lattice constants for CuInTe2 films annealed at 300°C were found to be and . The value of the grain size obtained in these films was of the order of 50 nm. The value of optical energy gap (0.97 eV) and the dispersive refractive index n(λ) for CuInTe2 film annealed at 300°C were evaluated by optical absorption measurement. 相似文献
19.
Y.B. Kishore Kumar 《Solar Energy Materials & Solar Cells》2009,93(8):1230-1237
Thin films of Cu2ZnSnS4 (CZTS), a potential candidate for absorber layer in thin film heterojunction solar cell, have been successfully deposited by spray pyrolysis technique on soda-lime glass substrates. The effect of substrate temperature on the growth of CZTS films is investigated. X-ray diffraction studies reveal that polycrystalline CZTS films with better crystallinity could be obtained for substrate temperatures in the range 643-683 K. The lattice parameters are found to be a=0.542 and c=1.085 nm. The optical band gap of films deposited at various substrate temperatures is found to lie between 1.40 and 1.45 eV. The average optical absorption coefficient is found to be >104 cm−1. 相似文献
20.
Toshiyuki Yamaguchi Yasutaka AsaiNaoyuki Oku Shigetoshi NiiyamaToshito Imanishi Shigeyuki Nakamura 《Solar Energy Materials & Solar Cells》2011,95(1):274-276
Cu(In,Ga)(S,Se)2 thin films with high Ga/III ratio (around 0.8) were prepared by sequential evaporation from CuGaSe2, CuInSe2, In2Se3 and Ga2Se3 compounds and then annealing in H2S gas atmosphere. The annealing temperature was varied from 400 to 500 °C. These samples were characterized by means of XRF, EPMA, XRD and SEM. The S/(S+Se) mole ratio in the thin films increased with increase in the annealing temperature, keeping the Cu, In and Ga contents nearly constant. The open circuit voltage increased and the short circuit current density decreased with increase in the annealing temperature. The best solar cell using Cu(In,Ga)(S,Se)2 thin film with Ga/(In+Ga)=0.79 and S/(S+Se)=0.11 annealed at 400 °C demonstrated Voc=535 mV, Isc=13.3 mA/cm2, FF=0.61 and efficiency=4.34% without AR-coating. 相似文献