Tem Study of GaSb/InAs Strained Layer Supeplattices

Cross-sectional TEM of GaSb/InAs superlattices grown by MBE on (100) GaAs and (100) GaSb substrates shows an unusual defect structure within the strained layers. Dislocations are present within the layers and at the interface. High-resolution TEM analysis of the structure of the InAs layers suggests that these layers grow by an island mechanism. A crystal structure different from the zinc blende, is found to be present within the GaSb layers.

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Formation of Large, Orientation-Controlled, Nearly Single Crystalline Si Thin Films on SiO2 Using Contact Printing of Rolled and Annealed Nickel Tapes

MRS Proceedings ◽

10.1557/proc-762-a17.13 ◽

2003 ◽

Vol 762 ◽

Author(s):

Hwang Huh ◽

Jung H. Shin

Keyword(s):

Electron Microscopy ◽

Thin Films ◽

High Resolution ◽

Amorphous Silicon ◽

Tem Analysis ◽

Contact Printing ◽

Single Crystalline ◽

High Resolution Tem ◽

Lateral Crystallization ◽

Si Films

AbstractAmorphous silicon (a-Si) films prepared on oxidized silicon wafer were crystallized to a highly textured form using contact printing of rolled and annealed nickel tapes. Crystallization was achieved by first annealing the a-Si film in contact with patterned Ni tape at 600°C for 20 min in a flowing forming gas (90 % N2, 10 % H2) environment, then removing the Ni tape and further annealing the a-Si film in vacuum for2hrsat600°C. An array of crystalline regions with diameters of up to 20 μm could be formed. Electron microscopy indicates that the regions are essentially single-crystalline except for the presence of twins and/or type A-B formations, and that all regions have the same orientation in all 3 directions even when separated by more than hundreds of microns. High resolution TEM analysis shows that formation of such orientation-controlled, nearly single crystalline regions is due to formation of nearly single crystalline NiSi2 under the point of contact, which then acts as the template for silicide-induced lateral crystallization. Furthermore, the orientation relationship between Si grains and Ni tape is observed to be Si (110) || Ni (001)

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Perovskite Solar Cells: Crystal Structure and Interface Architecture with High Resolution TEM Observations

10.29363/nanoge.ap-hopv.2018.028 ◽

2017 ◽

Author(s):

Satoshi Uchida ◽

Tae Woong Kim ◽

Ludmila Cojocaru ◽

Takashi Kondo ◽

Hiroshi Segawa

Keyword(s):

Crystal Structure ◽

Solar Cells ◽

High Resolution ◽

Perovskite Solar Cells ◽

High Resolution Tem

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High-Resolution TEM Analysis of Supported Metal Nanoparticles Combining with Image Simulation

Microscopy and Microanalysis ◽

10.1017/s143192761300977x ◽

2013 ◽

Vol 19 (S2) ◽

pp. 1556-1557 ◽

Cited By ~ 2

Author(s):

B. Zhang ◽

W. Zhang ◽

L. Shao ◽

D.S. Su

Keyword(s):

High Resolution ◽

Metal Nanoparticles ◽

Image Simulation ◽

Tem Analysis ◽

High Resolution Tem ◽

Supported Metal Nanoparticles ◽

Supported Metal

Extended abstract of a paper presented at Microscopy and Microanalysis 2013 in Indianapolis, Indiana, USA, August 4 – August 8, 2013.

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Epitaxial Growth of TiN on GaAs(100) by Pulsed Laser Deposition

MRS Proceedings ◽

10.1557/proc-285-343 ◽

1992 ◽

Vol 285 ◽

Cited By ~ 1

Author(s):

Tsvetanka S. Zheleva ◽

K. Jagannadham ◽

A. Kumar ◽

J. Narayan

Keyword(s):

High Resolution ◽

Pulsed Laser Deposition ◽

Epitaxial Growth ◽

Film Growth ◽

Pulsed Laser ◽

Laser Deposition ◽

Epitaxial Relationship ◽

Cross Sectional ◽

Tin Films ◽

High Resolution Tem

ABSTRACTEpitaxial growth of TiN films on GaAs(100) by pulsed laser deposition has been studied. Excimer KrF laser (λ=248 nm, τ=30 ns) has been used for deposition of TiN films in a chamber maintained at vacuum of ≤ 10−6 torr. The microstructure of TiN films has been characterized by x-ray diffraction and transmission electron microscopy (TEM). Cross-sectional high resolution TEM showed a smooth unreacted interface between the single crystalline TiN film and GaAs. The predominant epitaxial relationship was found to be [110]TiN//[010]GaAs, (220)TiN//(040)GaAs at a substrate temperature of 350°C. Modelling of epitaxial growth showed that the interfacial energy is an important term responsible for 45° rotation of the TiN unit cell with respect to that of GaAs. The high strain energy associated with the coherent epilayer is reduced by domain epitaxial growth. These films were characterized using high-resolution TEM techniques, and experimental results were rationalized by thin film growth modeling.

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Stresses experienced by AlN films grown on sapphire

MRS Proceedings ◽

10.1557/proc-0892-ff26-01 ◽

2005 ◽

Vol 892 ◽

Author(s):

Jie Bai ◽

J. Bai ◽

V.L. Tassev ◽

M. Lal Nakarmi ◽

W. Sun ◽

...

Keyword(s):

High Temperature ◽

High Resolution ◽

Lattice Mismatch ◽

Tem Analysis ◽

Mocvd Growth ◽

Compressive Stresses ◽

Show Evidence ◽

High Resolution Tem ◽

Final Stress ◽

Lower Temperature

AbstractThe evolution of stress during the MOCVD growth of AlN thin films on sapphire substrates under both low and high temperature conditions has been evaluated. The final stress state of the films is assumed to consist of the summation of stresses from three different sources: (1) the stress which arises from residual lattice mismatch between film and substrate i.e. that which persists after partial relaxation by misfit dislocation formation. The extent of relaxation is determined from High Resolution TEM analysis of the substrate/film interface; (2) the stress arising from the coalescence of the 3D islands nucleated in this high mismatch epitaxy process. This requires knowledge of the island sizes just prior to coalescence and this was provided by AFM studies of samples grown under the conditions of interest; and (3) the stress generated during post-growth cooling which arises from the differences in thermal expansion coefficient between AlN and sapphire. The final resultant stress, comprising the summation of stresses arising from these three sources, is found to be tensile in the sample grown at lower temperature and compressive in the sample grown at higher temperature. These results are in general qualitative agreement with results of TEM and High resolution X-ray diffraction (HRXRD) studies, which show evidence for tensile and compressive stresses in the low temperature and high temperature cases, respectively.

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High-resolution TEM and energy filtering TEM study of interfacial structure and reaction of diamond/Si in chemical vapor deposition

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100137732 ◽

1995 ◽

Vol 53 ◽

pp. 272-273

Author(s):

Fu-Rong Chen ◽

L. Chang ◽

C. J. Chen ◽

T. S. Lin

Keyword(s):

High Resolution ◽

Microwave Plasma ◽

Chemical Vapor ◽

Amorphous Layer ◽

Interfacial Structure ◽

Cross Sectional ◽

Energy Filtering ◽

Processing Step ◽

Microwave Plasma Cvd ◽

High Resolution Tem

Diamond film was grown using microwave plasma CVD technique which consists of three steps: carburization, bias and growth . The high resolution TEM (HRTEM) in cross-sectional view has been used to observe the evolution of interfacial structure in each processing step [1]. The chemistry near the interface was characterized with elemental mapping using energy-filtered imaging technique with Gatan imaging Filter (GIF) [2]. At the carburization stage, β-SiC, diamond particles and graphite plates have been observed in an amorphous layer. This amorphous layer was analysized to be carbon by energy filtering technique.As shown in the Fig. 1, β-SiC can form in epitaxial orientation with Si in the following stage of biasing. Graphite was not observed after the bias was applied. At the bias stage there is an interlayer of 6 nm thick between diamond and silicon substrate . From the high resoultion image in Fig. 2 (a), most of the regions of the interlayer are of amorphous characteristics which presents a barrier to identify the elemental compositions.

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Growth And High Resolution Tem Characterization of GexSi1−x/Si Hetero-Structures by Remote Plasma-Enhanced Chemical Vapor Deposition

MRS Proceedings ◽

10.1557/proc-235-811 ◽

1991 ◽

Vol 235 ◽

Author(s):

R. Qian ◽

I. Chung ◽

D. Kinosky ◽

T. Hsu ◽

J. Irby ◽

...

Keyword(s):

Chemical Vapor Deposition ◽

High Resolution ◽

Vapor Deposition ◽

Chemical Vapor ◽

Misfit Dislocations ◽

Remote Plasma ◽

Tem Analysis ◽

Plan View ◽

Lattice Constants ◽

High Resolution Tem

ABSTRACTRemote Plasma-enhanced Chemical Vapor Deposition (RPCVD) has been used to grow GexSi1−x/Si heteroepitaxial thin films at low temperatures (∼450°C). In situ RHEED has been used to confirm that smooth, single crystal heteroepitaxial films can be grown by RPCVD. Plan-view and cross-sectional TEM have been employed to study the microstructure of the heteroepitaxial films. Lattice imaging high resolution TEM (HRTEM) has shown perfect epitaxial lattice alignment at the heterojunction interfaces. GexSi1−x/Si films which exceed their CLT's appreciably show dense Moiré fringes under plan-view TEM. The spacings between the fringes have been used to estimate the relaxed lattice constants. In addition to the inhomogeneous strain observed in-XTEM, Selected Area electron Diffraction (SAD) analysis of the interfaces displays two split patterns. The spacings between the diffraction spots have been used to calculate the lattice constants in the epitaxial films in different crystal directions, which agree very well with the prediction by Vegard's law as well as the estimate from plan-view TEM analysis. HRTEM analysis also reveals the crystallographic nature of the interfacial misfit dislocations in the relaxed films.

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Imaging of III-V Compound Superlattices by Hrem and Rem

MRS Proceedings ◽

10.1557/proc-77-187 ◽

1986 ◽

Vol 77 ◽

Cited By ~ 2

Author(s):

B. C. De Cooman ◽

J. R. Conner ◽

S. R. Summerfelt ◽

S. McKernan ◽

C. B. Carter ◽

...

Keyword(s):

Electron Microscopy ◽

High Resolution ◽

Dark Field ◽

Contrast Effects ◽

Cross Sectional ◽

Dark Field Imaging ◽

Thin Foils ◽

High Resolution Tem ◽

Reflection Electron Microscopy ◽

Field Imaging

ABSTRACTTwo techniques for the analysis of III-V compound superlattices are examined. It has been proposed that high-resolution TEM of [100]-oriented thin foils would give an improvement in layer contrast compared with [110]-oriented thin foils; it is shown here that the contrast of [100]-oriented superlattices is not necessarily better. Moreover, both high resolution and conventional dark-field imaging may be subject to significant diffraction contrast effects resulting from the bending of the reflecting planes near the surface of the sample. Reflection electron microscopy (REM) of cross-sectional (110) cleavage planes can also yield dark-field superlattice images and selected area RHEED patterns can in principle be used to determine reliably the superlattice strain as surface effects are minimized.

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