Epitaxial Growth and Structure of Highly Mismatched Oxide Films with Rock-salt Structure on MgO

1996 ◽  
Vol 441 ◽  
Author(s):  
P. A. Langjahr ◽  
T. Wagner ◽  
F. F. Lange ◽  
M. Ruole
Keyword(s):  
Single Crystal ◽  
Epitaxial Growth ◽  
Lattice Mismatch ◽  
Coincidence Site Lattice ◽  
Chemical Solution Deposition Method ◽  
Orientation Relations ◽  
Heat Treated ◽  
Out Of Plane ◽  
Salt Structure ◽  
Good Lattice

AbstractCaO thin films were grown on (001) MgO single crystal substrates by a chemical solution deposition method to study the influence of a relatively high lattice mismatch (14%) on the epitaxial growth. In order to minimize an influence of a different crystal structure and chemistry between film and substrate, film and substrate were chosen to have the same structure (NaCl) and a similar chemistry. The films were heat treated until they broke up into single crystal islands on the MgO substrate. X-ray pole figure analysis and TEM observations of the CaO-films showed that most of the grains had a single out-of-plane orientation (111)CaO || (001)MgO, corresponding to two non-redundant, symmetry related in-plane variants [1 10](111)CaO || [110](001)MgO and [110](111)CaO || [110](001)MgO. A near coincidence site lattice (NCSL) model could be constructed for the interface, suggesting good lattice and charge matching for the observed orientation relations. The mechanisms and energetics leading to the experimentally observed orientation relations are discussed.

scholarly journals Solution-Processed Epitaxial Growth of MAPbI3 Single-Crystal Films for Highly Stable Photodetectors

2021 ◽  
Vol 8 ◽  
Author(s):  
Yubing Xu ◽  
Xin Wang ◽  
Jingda Zhao ◽  
Yuzhu Pan ◽  
Yuwei Li ◽  
...  
Keyword(s):  
Single Crystal ◽  
Light Emission ◽  
Lattice Mismatch ◽  
Precursor Solution ◽  
Fast Response ◽  
Solution Processed ◽  
Surface And Interface ◽  
Single Crystal Films ◽  
Crystal Films ◽  
Good Lattice

Recent years, organic-inorganic hybrid perovskites (OIHPs) have been widely used in applications, such as solar cells, lasers, light-emission diodes, and photodetectors due to their outstanding optoelectronic properties. Nowadays photodetectors based on perovskite films (PFs) suffer from surface and interface traps, which result from low crystalline quality of perovskite films and lattice mismatch between perovskite films and substrates. Herein, we fabricate MAPbI3 -(MA = CH3NH3) single-crystal films (SCFs) on MAPbBr3 single crystal substrates in MAPbI3 precursor solution during crystallization process via solution-processed epitaxy. Benefit from the good lattice matching, epitaxial MAPbI3 SCFs with high crystallinity and smooth morphology are of comparable quality to MAPbI3 PSCs and are of better quality than MAPbI3 polycrystalline films. Here we report that epitaxial MAPbI3 SCFs have a low trap density of 5.64×1011 cm–3 and a long carrier lifetime of 11.86 μs. In this work, photodetector based on epitaxial MAPbI3 single-crystal film (SCF) exhibits an excellent stability of a long-term stable response after 120 days, a fast response time of 2.21 μs, a high responsivity of 1.2 A W–1 and a high detectivity of 3.07 ×1012 jones.

Interface Reaction Enhanced Epitaxial Growth of Barium Ferrite Magnetic Thin Films

1994 ◽  
Vol 357 ◽  
Author(s):  
Jinshan Li ◽  
Robert Sinclair ◽  
Stephen S. Rosenblum ◽  
Hidetaka Hayashi
Keyword(s):  
Thin Films ◽  
Epitaxial Growth ◽  
Transition Layer ◽  
Barium Ferrite ◽  
Lattice Mismatch ◽  
Interface Reaction ◽  
Magnetic Thin Films ◽  
Point Of View ◽  
Si Substrates ◽  
Out Of Plane

AbstractUsing facing target sputtering, crystalline magnetoplumbite-type barium ferrite (BaFe12O19 or BaM) thin films have been prepared in-situ at a substrate temperature of 640°C without postdeposition annealing. BaM thin films grow randomly if they are directly deposited onto Si or thermally oxidized Si substrates. However, deposited onto a sputtered ZnO layer (∼230Å) on Si substrates, BaM thin films show excellent c-axis out-of-plane texture with a 0.2° c-axis dispersion angle, as indicated by X-ray diffraction (XRD) study. Cross section transmission electron microscopy (TEM) reveals that the textured films epitaxially grow on a transition layer, which is formed between BaM and ZnO. No direct epitaxial relation between BaM and ZnO was observed. This transition layer is identified by TEM and XRD as ZnFe2O4, which, from a structure point of view, reduces the lattice mismatch between BaM and ZnO, and also enhances the c-axis out-of-plane epitaxial growth.

Epitaxial growth of β–SiC thin films on a 6H–SiC substrate using the chemical solution deposition method

1997 ◽  
Vol 12 (11) ◽  
pp. 3099-3101 ◽  
Author(s):  
D. Heimann ◽  
T. Wagner ◽  
J. Bill ◽  
F. Aldinger ◽  
F. F. Lange
Keyword(s):  
Thin Films ◽  
Single Crystal ◽  
Epitaxial Growth ◽  
Thermal Treatments ◽  
Solution Deposition ◽  
Chemical Solution Deposition Method ◽  
Precursor Polymer ◽  
Transmission Electron ◽  
Different Temperatures ◽  
Sic Film

A polyvinylmethylsilane precursor has been used for the epitaxial growth of SiC thin films on 6H–SiC single crystal substrates. The films were prepared by dipping the single crystal 6H–SiC substrates into the precursor polymer solution with subsequent thermal treatments at different temperatures. Transmission electron microscopy (TEM) was used to characterize the microstructure and chemistry of the different SiC films. At 1100 °C, the film was amorphous and contained substantial oxygen. At 1600 °C, an epitaxial, single crystalline β–SiC film was observed.

Structural analysis of a Σ5 grain boundary in YBa2Cu3O7δ

1993 ◽  
Vol 51 ◽  
pp. 942-943
Author(s):  
J.-Y. Wang ◽  
Y. Zhu ◽  
A.H. King ◽  
M. Suenaga
Keyword(s):  
Grain Boundary ◽  
Lattice Mismatch ◽  
Weak Link ◽  
Coincidence Site Lattice ◽  
Large Angle ◽  
Dislocation Core ◽  
Superconducting Order Parameter ◽  
Outstanding Problem ◽  
Transmission Electron

One outstanding problem in YBa2Cu3O7−δ superconductors is the weak link behavior of grain boundaries, especially boundaries with a large-angle misorientation. Increasing evidence shows that lattice mismatch at the boundaries contributes to variations in oxygen and cation concentrations at the boundaries, while the strain field surrounding a dislocation core at the boundary suppresses the superconducting order parameter. Thus, understanding the structure of the grain boundary and the grain boundary dislocations (which describe the topology of the boundary) is essential in elucidating the superconducting characteristics of boundaries. Here, we discuss our study of the structure of a Σ5 grain boundary by transmission electron microscopy. The characterization of the structure of the boundary was based on the coincidence site lattice (CSL) model.Fig.l shows two-beam images of the grain boundary near the projection. An array of grain boundary dislocations, with spacings of about 30nm, is clearly visible in Fig. 1(a), but invisible in Fig. 1(b).

scholarly journals Experimental signatures of nodeless multiband superconductivity in a $$\hbox {2H-Pd}_{0.08} \hbox {TaSe}_2$$ single crystal

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Chanhee Kim ◽  
Dilip Bhoi ◽  
Yeahan Sur ◽  
Byung-Gu Jeon ◽  
Dirk Wulferding ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Single Crystal ◽  
Zero Magnetic Field ◽  
Anisotropy Ratio ◽  
Strong Temperature Dependence ◽  
Critical Fields ◽  
Band Theory ◽  
Plane Field ◽  
Low Field ◽  
Out Of Plane

AbstractIn order to understand the superconducting gap nature of a $$\hbox {2H-Pd}_{0.08} \hbox {TaSe}_2$$ 2H-Pd 0.08 TaSe 2 single crystal with $$T_{c} = 3.13 \text { K}$$ T c = 3.13 K , in-plane thermal conductivity $$\kappa $$ κ , in-plane London penetration depth $$\lambda _{\text {L}}$$ λ L , and the upper critical fields $$H_{c2}$$ H c 2 have been investigated. At zero magnetic field, it is found that no residual linear term $$\kappa _{0}/T$$ κ 0 / T exists and $$\lambda _{\text {L}}$$ λ L follows a power-law $$T^n$$ T n (T: temperature) with n = 2.66 at $$T \le \frac{1}{3}T_c$$ T ≤ 1 3 T c , supporting nodeless superconductivity. Moreover, the magnetic-field dependence of $$\kappa _{0}$$ κ 0 /T clearly shows a shoulder-like feature at a low field region. The temperature dependent $$H_{c2}$$ H c 2 curves for both in-plane and out-of-plane field directions exhibit clear upward curvatures near $$T_c$$ T c , consistent with the shape predicted by the two-band theory and the anisotropy ratio between the $$H_{c2}$$ H c 2 (T) curves exhibits strong temperature-dependence. All these results coherently suggest that $$\hbox {2H-Pd}_{0.08} \hbox {TaSe}_2$$ 2H-Pd 0.08 TaSe 2 is a nodeless, multiband superconductor.

Time Dependence of γ/γ' Lattice Mismatch in Creep-Deformed Single Crystal Superalloy SC16 at 1173 K

2007 ◽  
Vol 539-543 ◽  
pp. 3059-3063 ◽  
Author(s):  
G. Schumacher ◽  
N. Darowski ◽  
I. Zizak ◽  
Hellmuth Klingelhöffer ◽  
W. Chen ◽  
...  
Keyword(s):  
Single Crystal ◽  
Lattice Mismatch ◽  
Lattice Misfit ◽  
Peak Position ◽  
Single Crystal Superalloy ◽  
Tensile Creep ◽  
Full Width ◽  
X Ray Diffraction ◽  
X Ray ◽  
Time Period

The profiles of 001 and 002 reflections have been measured at 1173 K as a function of time by means of X-ray diffraction (XRD) on tensile-creep deformed specimens of single crystal superalloy SC16. Decrease in line width (full width at half maximum: FWHM) by about 7 % and increase in peak position by about 3x10-4 degrees was detected after 8.5x104 s. Broadening of the 002 peak profile indicated a more negative value of the lattice misfit after the same time period. The results are discussed in the context of the anisotropic arrangement of dislocations at the γ/γ’ interfaces during creep and their rearrangement during the thermal treatment at 1173 K.

Oxide Mediated Epitaxial Growth of CoSi2 in a Single Deposition Step

1999 ◽  
Vol 564 ◽  
Author(s):  
S. Ohmi ◽  
R. T. Tung
Keyword(s):  
Single Crystal ◽  
Epitaxial Growth ◽  
Diffusion Barrier ◽  
Blocking Layer ◽  
Deposition Step

AbstractA number of modifications of the oxide-mediated epitaxy (OME) technique are presented which have enabled the growth of thick (∼25–40nm) epitaxial CoSi2 layers in a single deposition sequence. The uses of (a) a thin Ti cap, (b) a thin Ti blocking layer, (c) the codeposition of Co-rich CoSix, and (d) the co-deposition of Col−xTix. have all been shown to lead to improved epitaxial quality over the pure Co OME process, for Co thickness greater than 6nm. Essentially uniform, single crystal silicide layers of over 25nm have been grown in a single deposition step. These results are supportive of the proposed role of a diffusion barrier/kinetics retarder on the part of the interlayer in the OME and the Ti-interlayer mediated epitaxy processes.

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