X-Ray Diffraction and Conductivity Studies in Polycrystalline Thin Films of CuInTe2 with Excess Copper Content

AbstractThe use of conventional θ/2θ diffraction methods for the characterization of polycrystalline thin films is not in general a satisfactory technique due to the relatively deep penetration of x-ray photons in most materials. Glancing incidence diffraction (GID) can compensate for the penetration problems inherent in the θ/2θ geometry. Parallel beam geometry has been developed in conjunction with GID to eliminate the focusing aberrations encountered when performing these types of measurements. During the past yearwe developed a parallel beam attachment which we have successfully configured to a number of systems.

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A Novel Technique to Determine Elastic Constants of Thin Films

MRS Proceedings ◽

10.1557/proc-1139-gg03-31 ◽

2008 ◽

Vol 1139 ◽

Author(s):

Klaus Martinschitz ◽

Rostislav Daniel ◽

Christian Mitterer ◽

Keckes Jozef

Keyword(s):

Thin Film ◽

Thin Films ◽

Elastic Moduli ◽

Elastic Anisotropy ◽

Interaction Model ◽

X Ray Diffraction ◽

X Ray ◽

Anisotropic Factor ◽

Polycrystalline Thin Films ◽

Cu Thin Film

AbstractA new X-ray diffraction technique to determine elastic moduli of polycrystalline thin films deposited on monocrystalline substrates is demonstrated. The technique is based on the combination of sin2ψ and X-ray diffraction wafer curvature techniques which are used to characterize X-ray elastic strains and macroscopic stress in thin film. The strain measurements must be performed for various hkl reflections. The stresses are determined from the substrate curvature applying the Stoney's equation. The stress and strain values are used to calculate hkl reflection dependent X-ray elastic moduli. The mechanical elastic moduli can be then extrapolated from X-ray elastic moduli considering film macroscopic elastic anisotropy. The derived approach shows for which reflection and corresponding value of the X-ray anisotropic factor Γ the X-ray elastic moduli are equal to their mechanical counterparts in the case of fibre textured cubic polycrystalline aggregates. The approach is independent of the crystal elastic anisotropy and depends on the fibre texture type, the texture sharpness, the amount of randomly oriented crystallites and on the supposed grain interaction model. The new method is demonstrated on a fiber textured Cu thin film deposited on monocrystalline Si(100) substrate. The advantage of the new technique remains in the fact that moduli are determined non-destructively, using a static diffraction experiment and represent volume averaged quantities.

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Characterization of Physical Properties of Thermally Evaporated Doped CdS Thin Films for Photovoltaics

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.510-511.156 ◽

2012 ◽

Vol 510-511 ◽

pp. 156-162 ◽

Cited By ~ 3

Author(s):

G.H. Tariq ◽

M. Anis-ur-Rehman

Keyword(s):

Thin Films ◽

Solar Cells ◽

Window Layer ◽

Bandgap Energy ◽

X Ray Diffraction ◽

X Ray ◽

Polycrystalline Thin Films ◽

Cds Thin Film ◽

Cds Thin Films ◽

Evaporation Technique

Polycrystalline thin films of Cadmium Sulfide (CdS) have been extensively studied for application as a window layer in CdTe/CdS and CIGS/CdS thin film solar cells. Higher efficiency of solar cells is possible by a better conductivity of a window layer, which can be achieved by doping these films with suitable elements. CdS thin films were deposited on properly cleaned glass substrate by thermal evaporation technique under vacuum2×10-5mbar. Films were structurally characterized by using X-ray diffraction. The X-ray diffraction spectra showed that the thin films were polycrystalline in nature. Aluminum was doped chemically in as deposited and annealed thin films by immersing films in AlNO33.9H2O solutions respectively. Comparison between the effects of different doping ratios on the structural and optical properties of the films was investigated. Higher doping ratios have improved the electrical properties by decreasing the resistivity of the films and slightly changed the bandgap energy Eg. The grain size, strain, and dislocation density were calculated for as-deposited and annealed films.

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TEM identification of secondary phases in non-stoichiometric polycrystalline CuInSe2 thin films

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100176150 ◽

1990 ◽

Vol 48 (4) ◽

pp. 604-605

Author(s):

J.P. Goral ◽

M.M. Al-Jassim ◽

D. Albin ◽

J.R. Tuttle ◽

R. Noufi

Keyword(s):

Thin Films ◽

Low Cost ◽

Growth Conditions ◽

Chalcopyrite Structure ◽

Secondary Phases ◽

X Ray Diffraction ◽

Cationic Sublattice ◽

X Ray ◽

Polycrystalline Thin Films ◽

Deposition Parameters

Polycrystalline thin films of CuInSe2 and CuGaSe2 are currently being developed as low-cost photovoltaic devices. These films are vacuum-deposited onto molybdenum metallized alumina substrates. The film composition may be varied by manipulation of the deposition parameters. For photovoltaic applications, the desired phase has a stoichiometry close to CuInSe2. This compound is a zincblende variant, the cations and anions occupying separate fcc sublattices. Under certain growth conditions, the Cu and In atoms adopt an ordered configuration within the cationic sublattice resulting in the tetragonal chalcopyrite structure. Even when the deposition parameters are manipulated to produce nominally stoichiometric films, powder x-ray traces often exhibit anomalous peaks indicative of the presence of impurity phases. The identification of these minority phases by x-ray diffraction alone is not possible in this materials system due to low peak intensity and overlap considerations. The formation of the secondary phases has a detrimental effect on the electrical and optical properties of the thin film device.

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Electrical Resistivity Improvement by Precipitation and Strain in Al-Cu Thin Films

Defect and Diffusion Forum ◽

10.4028/www.scientific.net/ddf.305-306.33 ◽

2010 ◽

Vol 305-306 ◽

pp. 33-37 ◽

Cited By ~ 1

Author(s):

S. Lallouche ◽

M.Y. Debili

Keyword(s):

Thin Films ◽

Copper Content ◽

Room Temperature ◽

Structural Features ◽

X Ray Diffraction ◽

X Ray ◽

Glass Substrates ◽

Transmission Electron ◽

Hall Method

This work deals with Al-Cu thin films, deposited onto glass substrates by RF (13.56MHz) magnetron sputtering, and annealed at 773K. The film thickness was approximately the same 3-4µm. They are characterized with respect to microstructure, grain size, microstrain, dislocation density and resistivity versus copper content. Al (Cu) deposits containing 1.8, 7.21, 86.17 and 92.5at%Cu have been investigated. The use of X-ray diffraction analysis and transmission electron microscopy lead to the characterization of different structural features of films deposited at room temperature (< 400K) and after annealing (773K). The resistivity of the films was measured using the four-point probe method. The microstrain profile obtained from XRD thanks to the Williamson-Hall method shows an increase with increasing copper content.

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High‐resolution x‐ray diffraction measurements of residual stresses in polycrystalline thin films deposited on single crystalline substrates

Applied Physics Letters ◽

10.1063/1.116958 ◽

1996 ◽

Vol 69 (27) ◽

pp. 4242-4244 ◽

Cited By ~ 7

Author(s):

M. Levit ◽

E. Zolotoyabko ◽

B.‐Z. Weiss

Keyword(s):

Thin Films ◽

High Resolution ◽

Residual Stresses ◽

X Ray Diffraction ◽

Single Crystalline ◽

X Ray ◽

Polycrystalline Thin Films

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One-Step Electrodeposition of CIGS Thin Films from Alcohol Solution on Flexible Substrate

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.368-372.472 ◽

2008 ◽

Vol 368-372 ◽

pp. 472-475 ◽

Cited By ~ 2

Author(s):

F. Long ◽

Wei Min Wang ◽

Jian Jun Li ◽

Zheng Guang Zou

Keyword(s):

Electron Microscopy ◽

Thin Films ◽

Flexible Substrate ◽

Alcohol Solution ◽

X Ray Diffraction ◽

X Ray ◽

Polycrystalline Thin Films ◽

One Step ◽

Potential Curves ◽

Scanning Electron

CuIn1-xGaxSe2 (CIGS) precursor films were fabricated on Mo foils by one-step electrodeposition in water and alcohol solutions. The precursor films were annealed in Ar atmosphere at 450°C to synthesize the polycrystalline thin films. The current density vs. potential curves of Cu2+, In3+, Ga3+ and Se4+ was studied by cyclic voltammetry. The compositions of CIGS, were analyzed by energy dispersive X-ray spectrum. The morphology and phase structure of films was characterized by scanning electron microscopy and X-ray diffraction, respectively.

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Elastic Properties of Supported Polycrystalline Thin Films and Multilayers: an X-Ray Diffraction Study

Materials Science Forum ◽

10.4028/www.scientific.net/msf.426-432.3409 ◽

2003 ◽

Vol 426-432 ◽

pp. 3409-3414

Author(s):

Philippe Goudeau ◽

Pascale Villain ◽

Nobumichi Tamura ◽

Pierre Olivier Renault ◽

K.F. Badawi ◽

...

Keyword(s):

Thin Films ◽

Diffraction Study ◽

Elastic Properties ◽

X Ray Diffraction ◽

X Ray ◽

Polycrystalline Thin Films

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Glancing Incidence X-Ray Diffraction of Polycrystalline Thin Films

MRS Proceedings ◽

10.1557/proc-865-f4.1 ◽

2005 ◽

Vol 865 ◽

Cited By ~ 28

Author(s):

Brian E. McCandless

Keyword(s):

Thin Films ◽

Critical Incident ◽

Inorganic Compounds ◽

Incident Beam ◽

Refraction Index ◽

X Ray Diffraction ◽

X Ray ◽

Chemical Surface ◽

Native Oxides ◽

Polycrystalline Thin Films

AbstractGlancing incidence x-ray diffraction (GIXRD) is a powerful diagnostic tool for nondestructive analysis of thin film materials and structures. GIXRD fundamentals and experimental techniques and results are presented with respect to polycrystalline thin-films. The refraction index and critical incident beam angle are calculated for selected elemental and inorganic compounds. Quantitative GIXRD analysis with Cu Kα radiation is applied to several problems: recrystallization of ultra-thin chemical surface deposited CdS films; compositional grading in CuIn1-xGaxSe2 films; formation of native oxides on CdTe films; interdiffusion between CdTe and CdS; Te film thickness determination on etched CdTe; and correlation of inplane residual stress with deposition conditions for sputtered Mo films.

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