Epitaxial Order Driven by Surface Corrugation: Quinquephenyl Crystals on a Cu(110)-(2×1)O Surface

A 30 nm thick quinquephenyl (5P) film was grown by molecular beam deposition on a Cu(110)(2×1)O single crystal surface. The thin film morphology was studied by light microscopy and atomic force microscopy and the crystallographic structure of the thin film was investigated by X-ray diffraction methods. The 5P molecules crystallise epitaxially with (201)5P parallel to the substrate surface (110)Cu and with their long molecular axes parallel to [001]Cu. The observed epitaxial alignment cannot be explained by lattice matching calculations. Although a clear minimum in the lattice misfit exists, it is not adapted by the epitaxial growth of 5P crystals. Instead the formation of epitaxially oriented crystallites is determined by atomic corrugations of the substrate surface, such that the initially adsorbed 5P molecules fill with its rod-like shape the periodic grooves of the substrate. Subsequent crystal growth follows the orientation and alignment of the molecules taken within the initial growth stage.

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Effect of the substrate surface condition on the Ni(thin film)/SiC(0001) interfacial reaction

Journal of Materials Research ◽

10.1557/jmr.2007.0312 ◽

2007 ◽

Vol 22 (9) ◽

pp. 2522-2530 ◽

Cited By ~ 3

Author(s):

Cory R. Dean ◽

Kevin Robbie ◽

Lynnette D. Madsen

Keyword(s):

Thin Film ◽

Substrate Surface ◽

Surface Condition ◽

Intercalation Compound ◽

X Ray Diffraction ◽

Graphite Phase ◽

X Ray ◽

Force Microscopy ◽

Atomic Force ◽

Graphite Intercalation

The effect of the substrate surface, structure, and chemistry on the interfacial interaction in Ni(thin film)/SiC was examined, with a focus on the recently discovered formation of a nickel intercalated graphite phase. Very thin Ni films (∼7 nm) were deposited onto heated 6H–SiC(0001) substrates prepared with: (i) an oxide layer, (ii) a surface reconstruction, and (iii) a pristine surface (no oxide and no reconstruction), followed by further annealing. Characterization using x-ray diffraction and atomic force microscopy revealed remarkable differences between the samples in terms of both surface morphology and crystallography. Nickel silicides were present in all samples; however, the phase composition differed depending on sample preparation. Furthermore, the pristine surface was the only one that clearly promoted the growth of the nickel graphite intercalation compound (Ni-GIC).

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Effect of ultra-thin Cu underlayer on the magnetic properties of Ni80Fe50 / Fe50Mn50 films

MRS Proceedings ◽

10.1557/proc-562-69 ◽

1999 ◽

Vol 562 ◽

Author(s):

C. Liu ◽

L. Shen ◽

H. Jiang ◽

D. Yang ◽

G. Wu ◽

...

Keyword(s):

Thin Film ◽

Atomic Force Microscopy ◽

Exchange Bias ◽

Film Material ◽

X Ray Diffraction ◽

X Ray ◽

Force Microscopy ◽

Atomic Force ◽

Maximum Value ◽

Film Roughness

ABSTRACTThe Ni80Fe20/Fe50Mn50,thin film system exhibits exchange bias behavior. Here a systematic study of the effect of atomic-scale thin film roughness on coercivity and exchange bias is presented. Cu (t) / Ta (100 Å) / Ni80Fe20 (100 Å) / Fe50Mno50 (200 Å) / Ta (200 Å) with variable thickness, t, of the Cu underlayer were DC sputtered on Si (100) substrates. The Cu underlayer defines the initial roughness that is transferred to the film material since the film grows conformal to the initial morphology. Atomic Force Microscopy and X-ray diffraction were used to study the morphology and texture of the films. Morphological characterization is then correlated with magnetometer measurements. Atomic Force Microscopy shows that the root mean square value of the film roughness exhibits a maximum of 2.5 Å at t = 2.4 Å. X-ray diffraction spectra show the films are polycrystalline with fcc (111) texture and the Fe50Mn50 (111) peak intensity decreases monotonically with increasing Cu thickness, t. Without a Cu underlayer, the values of the coercivity and loop shift are, Hc = 12 Oe and Hp = 56 Oe, respectively. Both the coercivity and loop shift change with Cu underlayer thickness. The coercivity reaches a maximum value of Hc= 36 Oe at t = 4 Å. The loop shift exhibits an initial increase with t, reaches a maximum value of HP = 107 Oe at t = 2.4 Å, followed by a decrease with greater Cu thickness. These results show that a tiny increase in the film roughness has a huge effect on the exchange bias magnitude.

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Optical Functions of Thin-Film Polycrystalline Chalcopyrite CuIn1-xGaxSe2

MRS Proceedings ◽

10.1557/proc-763-b1.8 ◽

2003 ◽

Vol 763 ◽

Cited By ~ 1

Author(s):

Sung-Ho Han ◽

Dean H. Levi ◽

Hamda A. Althani ◽

Falah S. Hasoon ◽

Raghu N. Bhattacharya ◽

...

Keyword(s):

Thin Film ◽

Dielectric Function ◽

Layer Structure ◽

X Ray Diffraction ◽

Force Microscopy ◽

Optical Functions ◽

Atomic Force ◽

Polycrystalline Thin Films ◽

Cigs Solar Cells ◽

Compare And Contrast

AbstractThe highest efficiency CuIn1-xGaxSe2 (CIGS) solar cells use thin-film polycrystalline CIGS absorber layers. We have applied variable angle spectroscopic ellipsometry (VASE) to characterize the dielectric functions of polycrystalline thin films of CIGS with Ga: (In + Ga) ratios ranging from 0.18 to 1.0. The Cu: (In + Ga) ratios in these films are approximately 0.90, which is the ratio that yields the highest efficiency CIGS devices. Spectra were measured over the energy range 0.7 to 5.0 eV at room temperatures. Models used to analyze the ellipsometry data include the full multi-layer structure of the sample, which enables us to report the actual dielectric function rather than the pseudo-dielectric function. We present data on how the critical points change with composition, and compare and contrast our results with measurements of single-crystal and bulk polycrystalline samples reported in the literature. Auger electron spectroscopy, atomic force microscopy, and X-ray diffraction have been used to verify the homogeneity, surface roughness, and phase purity, respectively.

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Facile synthesis of TiO2 film on glass for the photocatalytic removal of rhodamine B and tetracycline hydrochloride

Materials Express ◽

10.1166/mex.2019.1522 ◽

2019 ◽

Vol 9 (5) ◽

pp. 437-443 ◽

Cited By ~ 3

Author(s):

Jiaxin Li ◽

Zhi Chen ◽

Jianfei Fang ◽

Qian Yang ◽

Xiuru Yang ◽

...

Keyword(s):

Thin Film ◽

Organic Pollutants ◽

Reaction System ◽

Practical Application ◽

X Ray Diffraction ◽

Force Microscopy ◽

Atomic Force ◽

Photocatalytic Removal ◽

Coating Method ◽

Potential Applications

Photocatalysis is one of the efficient approaches for pollution control in water. However, the traditional photocatalysts used for the removal of organic pollutants are in powder form, which makes it difficult to recover them from the suspended reaction system. On the contrary, thin film photocatalyst is easy to be retrieved and possesses unique feature for practical application. In present work, stable TiO2 sol suspension was prepared and amorphous TiO2 thin film was then immobilized upon glass substrate through facile spin coating method. The thickness of film could be simply controlled by changing the number of coatings, and anatase TiO2 film could be formed after calcination. The prepared thin films were characterized with X-ray diffraction (XRD), ultravioletvisible spectrophotometry (UV-vis), scanning electron microscopy (SEM) and atomic force microscopy (AFM). The photodegradations of organic pollutants including colored dye and colorless antibiotic were tested and found to be thickness-dependent. Additionally, the prepared film photocatalst has good stability and may have potential applications in wastewater treatment.

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Self-Assembled Growth of Highly Oriented Para- Sexiphenyl Thin Films Controlled by Elastic Strain

MRS Proceedings ◽

10.1557/proc-665-c5.24 ◽

2001 ◽

Vol 665 ◽

Cited By ~ 1

Author(s):

Andrei Yu. Andreev ◽

Helmut Sitter ◽

Christoph J. Brabec ◽

Peter Hinterdorfer ◽

Günter Springholz ◽

...

Keyword(s):

Thin Films ◽

Substrate Surface ◽

Growth Time ◽

Crystallographic Structure ◽

Force Microscopy ◽

Atomic Force ◽

Transmission Electron ◽

Degree Of Anisotropy ◽

Figure Technique ◽

Crystallographic Planes

ABSTRACTWe have studied the structure and growth regularities of highly ordered para-sexiphenyl (C36H26) thin films deposited by Hot Wall Epitaxy on mica. In particular, atomic force microscopy (AFM) was used to investigate the early growth stage of these films, in order to find the process controlling parameters. It was shown that the substrate temperature and the growth time are important parameters for control of the film morphology, in terms of the degree of anisotropy and long range order. X-ray diffraction pole figure technique and transmission electron microscopy were also used to characterize the crystallographic structure of the thicker films. We have shown that the highly ordered crystallites of para-sexiphenyl (showing needle-like morphology by AFM) are oriented with their (11 1 ) or (11 2 ) crystallographic planes parallel to the substrate surface. For each of these two orientations there are two opposite directions for growth of crystallites reflecting the two-fold symmetry of the mica surface.

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Stability and Structural Characterization of Epitaxial NdNiO3 Films Grown by Pulsed Laser Deposition

MRS Proceedings ◽

10.1557/proc-658-gg3.27 ◽

2000 ◽

Vol 658 ◽

Cited By ~ 2

Author(s):

Trong-Duc Doan ◽

Cobey Abramowski ◽

Paul A. Salvador

Keyword(s):

Thin Films ◽

Pulsed Laser Deposition ◽

Substrate Surface ◽

Pulsed Laser ◽

Laser Deposition ◽

X Ray Diffraction ◽

Force Microscopy ◽

Atomic Force ◽

Monoclinic Distortion

ABSTRACTThin films of NdNiO3 were grown using pulsed laser deposition on single crystal substrates of [100]-oriented LaAlO3 and SrTiO3. X-ray diffraction and reflectivity, scanning electron microscopy, and atomic force microscopy were used to characterize the chemical, morphological and structural traits of the thin films. Single-phase epitaxial films are grown on LaAlO3 and SrTiO3 at 625°C in an oxygen pressure of 200 mTorr. At higher temperatures, the films partially decompose to Nd2NiO4 and NiO. The films are epitaxial with the (101) planes (orthorhombic Pnma notation) parallel to the substrate surface. Four in-plane orientational variants exist that correspond to the four 90° degenerate orientations of the film's [010] with respect to the in-plane substrate directions. Films are observed to be strained in accordance with the structural mismatch to the underlying substrate, and this leads, in the thinnest films on LaAlO3, to an apparent monoclinic distortion to the unit cell.

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Assembly of thin Film Dielectrics by Sequential Adsorption Reactions of Unilamellar Inorganic Colloids

MRS Proceedings ◽

10.1557/proc-446-377 ◽

1996 ◽

Vol 446 ◽

Cited By ~ 1

Author(s):

Mingming Fang ◽

Chy Hyung Kim ◽

Anthony C. Sutorik ◽

David M. Kaschak ◽

Thomas E. Mallouk

Keyword(s):

Thin Film ◽

Inorganic Materials ◽

Silicon Surfaces ◽

X Ray Diffraction ◽

Alkali Cations ◽

Force Microscopy ◽

Atomic Force ◽

Sequential Adsorption ◽

Thin Film Dielectrics ◽

Layered Perovskites

AbstractSeveral layered inorganic materials (e.g. KCa2Nb3O10, KTiNbO5, and CsPb2Nb3O10) were prepared and their alkali cations exchanged by in aqueous acid. A fraction of the interlayer protons of HCa2Nb3O10 and HTiNbO5 can be replaced by tetra-n-butylammonium (TBA+), by reaction with TBA+OH. Intercalation of a sufficient amount of TBA+ causes complete exfoliation, and single, nanometer-thick sheets of these materials are thus obtained. By sequential adsorption of these two-dimensional colloidal polyanions and polymeric cations, monolayer sheets of layered perovskites can be stacked on silicon surfaces to give thin films of any desired thickness. The layered materials, the exfoliated colloids, and the thin film multilayers on silicon were studied by X-ray diffraction, transmission electronic microscopy (TEM), ellipsometry, and atomic force microscopy (AFM). The dielectric properties of the related bulk materials were measured, and are also discussed.

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Atomic force microscopy and x-ray diffraction studies of aluminum-induced crystallization of amorphous silicon in Al/α-Si:H, α-Si:H/Al, and Al/α-Si:H/Al thin film structures

Journal of Vacuum Science & Technology B Microelectronics Processing and Phenomena ◽

10.1116/1.1570847 ◽

2003 ◽

Vol 21 (3) ◽

pp. 1037 ◽

Cited By ~ 13

Author(s):

Ram Kishore ◽

Arshad Shaik ◽

H. A. Naseem ◽

W. D. Brown

Keyword(s):

Thin Film ◽

Atomic Force Microscopy ◽

Amorphous Silicon ◽

X Ray Diffraction ◽

X Ray ◽

Force Microscopy ◽

Atomic Force ◽

Al Thin Film ◽

Induced Crystallization ◽

Aluminum Induced Crystallization

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Electrochemical Behavior of LiFePO4 Thin Film Prepared by RF Magnetron Sputtering in Li2SO4 Aqueous Electrolyte

International Journal of Nanoscience ◽

10.1142/s0219581x14600278 ◽

2015 ◽

Vol 14 (01n02) ◽

pp. 1460027 ◽

Cited By ~ 2

Author(s):

Jiaxiong Wu ◽

Wei Cai ◽

Guangyi Shang

Keyword(s):

Thin Film ◽

Magnetron Sputtering ◽

Rf Magnetron Sputtering ◽

Ion Diffusion ◽

X Ray Diffraction ◽

Electrochemical Tests ◽

Force Microscopy ◽

Atomic Force ◽

Li Ion ◽

Deposited Film

LiFePO 4 films were deposited on Au / Si substrate by radio-frequency magnetron sputtering. The effect of annealing on the crystallization and morphology of LiFePO 4 thin film has been investigated. X-ray diffraction revealed that the films through annealing were well crystallized compared with as-deposited films. The surface morphology of the thin film was also observed by scanning electron microscopy (SEM) and atomic force microscopy (AFM). Electrochemical tests in 1M Li 2 SO 4 showed that the annealed thin film in 500°C exhibits larger Li -ion diffusion coefficient (3.46 × 10-7 cm2s-1) than as-deposited film and powder. Furthermore, cyclic voltammetry demonstrate a well-defined lithium intercalation/deintercalation reaction at around 0.45 V versus SCE (i.e., 3.6 V versus Li +/ Li ), suggesting that the annealed LiFePO 4 thin film is a promising candidate cathode film for lithium microbatteries.

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Development and Characterization for Solar Photovoltaic Cell Based on Cu2ZnSn(S0.2Se0.8)4 Thin Film

Nanoscience and Nanotechnology Letters ◽

10.1166/nnl.2020.3119 ◽

2020 ◽

Vol 12 (3) ◽

pp. 306-316

Author(s):

Sadanand ◽

Pravin Kumar Singh ◽

Pooja Lohia ◽

D. K. Dwivedi ◽

Fahad A. Alharthi ◽

...

Keyword(s):

Thin Film ◽

Solar Cells ◽

Photovoltaic Cell ◽

Maximum Efficiency ◽

Solar Photovoltaic ◽

X Ray Diffraction ◽

Force Microscopy ◽

Atomic Force ◽

Photovoltaic Solar Cells ◽

Efficient Solar Cell

CZTSSe materials have been studied for a highly efficient solar cell. In this paper, Cu2ZnSn(S0.2Se0.8)4 (CZTSSe) thin film was prepared and its application to photovoltaic solar cells was studied. The CZTSSe thin film was deposited using facile thermal evaporation process and examined by various techniques including X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), atomic force microscopy (AFM), Raman-scattering and Fourier transform infrared (FTIR) spectroscopy. Interestingly, the synthesized CZTSSe thin are exhibiting broad-spectrum absorption. The I–V characteristics were performed to study the photoresponse of CZTSSe nanofilm. By the numerical simulation, the observed maximum efficiency of the fabricated device was ∼16.5%. Therefore, the present study reveals that Cu2ZnSn(S0.2Se0.8)4 thin films could be used as an effective absorber layer for efficient solar cells applications.

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