In-Situ investigation of Structure and Magnetic Properties of the Epitaxial System Pd(111)/Fe(110) on W(110) by Means of Brillouin Spectroscopy

The in-situ observation of magnetostatic spin waves by Brillouin spectroscopy offers a versatile dynamical probe for the investigation of magnetic properties of thin films. The measured spin wave spectra of thin films contain a variety of information about their magnetic as well as structural properties. The frequency of a spin wave allows to determine, e.g., the g-factor, the magnetic anisotropy constants and also the saturation magnetization. The spectral line shape allows conclusions about the film quality, i.e., steps or islands. Furthermore, the unidirectional propagation of the surface spin wave with respect to the magnetization allows to measure the coercitivity field of a film. The latter can be used as an additional characterization parameter of a magnetic film.

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In-Situ Investigation of Cu-In-Se Reactions by Thin Film Calorimetry

MRS Proceedings ◽

10.1557/proc-485-173 ◽

1997 ◽

Vol 485 ◽

Cited By ~ 7

Author(s):

D. Wolf ◽

G. Müller

Keyword(s):

Thin Film ◽

Thin Films ◽

Equilibrium Phase ◽

Reaction Times ◽

Practical Interest ◽

Ex Situ ◽

In Situ Observation ◽

Flux Agent ◽

In Situ Investigation

AbstractStudies of the reaction path during annealing of Cu-In-Se thin films for solar cell absorbers have been limited up to now to ex-situ analyses of the phase composition by X-Ray Diffraction (XRD) after processing by a specific temperature-time program. As an indirect method, the application of ex-situ XRD is not sufficient for the determination of reaction temperatures and reaction times for setting up a general model of CIS-formation.We show in this paper that the use of a calorimetric method (Thin Film Calorimetry, TFC) offers the advantage of a direct (in-situ) observation of thin film reactions. Special care is taken to use film thicknesses of practical interest for industrial application (1.5 – 3 μm). In a first step we show results of binary reactions in the Cu-In, In-Se and Cu-Se systems. Their knowledge is necessary for understanding the processes involved in the ternary CIS-layers. It turned out that thin Cu-In and Cu-Se films react already at room temperature and behave as predicted by the bulk equilibrium phase diagrams during heating. In-Se thin films show prominent exothermic reactions starting with the melting of In. The first phase to be formed is generally In2Se which is then converted to more Se-rich compounds. In ternary Cu-In-Se films (Cu/In = 1.00) we observe transitions of the Cu-Se-system which can be attributed to the decomposition of CuSe2 and CuSe. Consequences for the model of improved CIS-growth by a Cu-Se flux agent are discussed.

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Thin film bi-epitaxy and transition characteristics of TiO2/TiN buffered VO2 on Si(100) substrates

MRS Advances ◽

10.1557/adv.2016.544 ◽

2016 ◽

Vol 1 (37) ◽

pp. 2635-2640 ◽

Cited By ~ 5

Author(s):

Adele Moatti ◽

Reza Bayati ◽

Srinivasa Rao Singamaneni ◽

Jagdish Narayan

Keyword(s):

Thin Film ◽

Thin Films ◽

Magnetic Properties ◽

Frequency Factor ◽

Misfit Strain ◽

Buffer Layers ◽

Intrinsic Defects ◽

Domain Matching Epitaxy ◽

Out Of Plane

ABSTRACTBi-epitaxial VO2 thin films with [011] out-of-plane orientation were integrated with Si(100) substrates through TiO2/TiN buffer layers. At the first step, TiN is grown epitaxially on Si(100), where a cube-on-cube epitaxy is achieved. Then, TiN was oxidized in-situ ending up having epitaxial r-TiO2. Finally, VO2 was deposited on top of TiO2. The alignment across the interfaces was stablished as VO2(011)║TiO2(110)║TiN(100)║Si(100) and VO2(110) /VO2(010)║TiO2(011)║TiN(112)║Si(112). The inter-planar spacing of VO2(010) and TiO2(011) equal to 2.26 and 2.50 Å, respectively. This results in a 9.78% tensile misfit strain in VO2(010) lattice which relaxes through 9/10 alteration domains with a frequency factor of 0.5, according to the domain matching epitaxy paradigm. Also, the inter-planar spacing of VO2(011) and TiO2(011) equals to 3.19 and 2.50 Å, respectively. This results in a 27.6% compressive misfit strain in VO2(011) lattice which relaxes through 3/4 alteration domains with a frequency factor of 0.57. We studied semiconductor to metal transition characteristics of VO2/TiO2/TiN/Si heterostructures and established a correlation between intrinsic defects and magnetic properties.

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Fabrication of Polycrystalline Silicon on Glass from Fluorinated Precursors with the Aid of Atomic Hydrogen

MRS Proceedings ◽

10.1557/proc-403-391 ◽

1995 ◽

Vol 403 ◽

Cited By ~ 1

Author(s):

T. Akasaka ◽

D. He ◽

I. Shimizu

Keyword(s):

Thin Films ◽

Atomic Hydrogen ◽

Polycrystalline Silicon ◽

In Situ Observation ◽

Layer By Layer ◽

High Quality ◽

Deposition Parameters ◽

Columnar Grains ◽

Step Growth

AbstractHigh quality polycrystalline silicon was made on glass from fluorinated precursors by two step growth, i.e., (1) formation of seed crystals on glass by layer-by-layer(LL) technique and (2) grain-growth on the seeds. In LL technique, deposition of ultra-thin films and treatment with atomic hydrogen was repeated alternately. Columnar grains with 200 nm dia were grown epitaxy-like on the seeds by optimizing the deposition parameters under in situ observation with spectroscopic ellipsometry.

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