X-Ray Rocking Curve Characterization of SiC Substrates

2008 ◽  
Vol 600-603 ◽  
pp. 361-364
Author(s):  
Murugesu Yoganathan ◽  
Ping Wu ◽  
Ilya Zwieback
Keyword(s):  
Growth Process ◽  
Crystal Quality ◽  
Nondestructive Technique ◽  
Lattice Curvature ◽  
Rocking Curve ◽  
X Ray ◽  
Typical Variation

X-ray rocking curve characterization is a relatively fast and nondestructive technique that can be utilized to evaluate the crystal quality of SiC substrates. The contribution of lattice curvature to rocking curve broadening is estimated, and shown to be the major contribution to the measured broadening (FWHM). The feedback on lattice quality is used to optimize our SiC growth process. In the optimized growth runs, the typical variation in rocking curve sample angle Ω across the entire 3” diameter wafer is about 0.2 degrees. Possible mechanisms leading to changes in the lattice curvature are discussed.

X-Ray Interference Measurements of Ultrathin Semiconductor Layers

1989 ◽  
Vol 145 ◽  
Author(s):  
C.R. Wie
Keyword(s):  
X Ray Diffraction ◽  
Nondestructive Technique ◽  
Interference Structure ◽  
Rocking Curve ◽  
X Ray ◽  
Double Heterojunction ◽  
Strained Quantum Well ◽  
Interference Measurements ◽  
Strained Layer Superlattices

AbstractWe present various x-ray diffraction phenomena from semiconductor hetero-epitaxial layers. Each of these phenomena gives useful information on the layers. Knowing what to look for in the x-ray rocking curve (XRC) can make this nondestructive technique a very powerful tool for characterization of a few A-several g.tm thick layers We discuss the use of individual Bragg peak, diffraction fringe, and interference structure to obtain layer information. We particularly emphasize the use of x-ray interference in studying buried strained quantum well or quantum barrier layers. We present experimental rocking curves of an AlGaAs/GaAs double heterojunction laser structure and GaInAs/GaAs strained layer superlattices in both <001> and <111> orientations.

Characterization of SiC Substrates Using X-Ray Rocking Curve Mapping

2006 ◽  
Vol 527-529 ◽  
pp. 729-732 ◽  
Author(s):  
Murugesu Yoganathan ◽  
Ejiro Emorhokpor ◽  
Thomas Kerr ◽  
A. Gupta ◽  
C.D. Tanner ◽  
...  
Keyword(s):  
Plastic Deformation ◽  
Lattice Distortion ◽  
Lattice Strain ◽  
Bragg Reflection ◽  
Sharp Change ◽  
Lattice Curvature ◽  
Rocking Curve ◽  
X Ray ◽  
Grain Misorientation

SiC substrates produced at II-VI, Inc. have been characterized using x-ray rocking curve mapping (topography). The rocking curves have been measured in the -scan mode for the (0006) Bragg reflection of 6H and the (0004) reflection of 4H SiC substrates. The maps contain information extracted from the rocking curves, such as the peak angle () and the rocking curve broadening (FWHM). In the case when lattice distortion is present due to the elastic or plastic deformation, the peak angle () changes gradually upon scanning, with the d/dx gradient proportional to the lattice curvature in the plane of diffraction. Multi-peak reflections and/or sharp change in the value of indicate the presence of misoriented grains. X-ray rocking curve mapping of SiC substrates yields excellent measures of crystalline quality that contain important information on the lattice strain and sub-grain misorientation.

Growth and Characterization of Large Diameter 6H and 4H SiC Single Crystals

2006 ◽  
Vol 527-529 ◽  
pp. 43-46 ◽  
Author(s):  
A. Gupta ◽  
E. Semenas ◽  
Ejiro Emorhokpor ◽  
J. Chen ◽  
Ilya Zwieback ◽  
...  
Keyword(s):  
Single Crystals ◽  
Growth Process ◽  
Large Diameter ◽  
Growth Technique ◽  
Rocking Curve ◽  
X Ray ◽  
The Past ◽  
Type 3 ◽  
Insulating Properties

Over the past year, II-VI has transitioned from 2” to 3” commercial SiC substrates. Large-diameter semi-insulating 6H-SiC and n-type 4H-SiC single crystals are grown using the Advanced PVT growth process. Expansion of boule diameter from 2 to 3 and up to 4.25 inches has been carried out using a specially designed growth technique. Stable semi-insulating properties in 6H-SiC are achieved by precise vanadium compensation. The technique of compensation is optimized to produce a controlled and spatially uniform distribution of vanadium and high and spatially uniform electrical resistivity reaching 10 10 – 1011 ·cm. N-type 3-inch 4H-SiC crystals are grown using doping with nitrogen, and 3-inch 4H-SiC substrates show uniform resistivity of about 0.018 ·cm. The best quality semiinsulating (SI) 3” 6H-SiC substrates demonstrate micropipe density of 3 cm-2, and n-type 3” 4H-SiC substrates - about 1 cm-2. X-ray rocking curve topography of the produced 3” SiC substrates is used for evaluation of their crystal quality.

Characterization of CdTe:Zn:V crystals grown under microgravity conditions

2002 ◽  
Vol 17 (12) ◽  
pp. 3037-3041 ◽  
Author(s):  
V. Corregidor ◽  
V. Babentsov ◽  
J. L. Castaño ◽  
M. Fiederle ◽  
T. Feltgen ◽  
...  
Keyword(s):  
Growth Process ◽  
Structural Quality ◽  
Seed Region ◽  
Photoluminescence Spectra ◽  
Positive Role ◽  
X Ray ◽  
Microgravity Conditions

CdTe:Zn:V crystals grown by the seeded Bridgman method in microgravity conditions during the STS95-Spacelab-AGHF-1 mission and in the ground laboratory (l-g) were analyzed and compared. The results obtained clearly show that the structural quality of the space crystal is better. Density of inclusions, concentration of dislocations, and presence of stresses are lower in the microgravity-grown (μ-g) crystal. The l-g crystal contains twins and grains from the beginning of the growth process, that is, from the near-seed region. In general, the concentration of inclusions and amount of segregated impurities on the l-g crystal are larger than in the μ-g crystal. X-ray rocking curves and low-temperature photoluminescence spectra demonstrate the relatively high quality of both crystals on a microscale at the beginning of the growth and show that the l-g conditions were worse at the end. The results of this investigation demonstrate a positive role of contactless growth and μ-g conditions in the melt in suppressing the creation of inclusions and dislocations.

Modified Hot-Zone Design of Growth Cell for Reducing the Warpage of 6”-SiC Wafer

2020 ◽  
Vol 1004 ◽  
pp. 32-36
Author(s):  
Byung Kyu Jang ◽  
Jong Hwi Park ◽  
Jung Woo Choi ◽  
Eunsu Yang ◽  
Jung Gyu Kim ◽  
...  
Keyword(s):  
Growth Process ◽  
New Materials ◽  
Rocking Curve ◽  
X Ray ◽  
Maximum Value ◽  
Sic Wafer ◽  
Reducing Stress ◽  
Hot Zone ◽  
Better Than

The modified hot-zone design, consisting of a new design and new materials for the backside of SiC seed holder was adopted for reducing stress in grown SiC crystal ingot and for reducing the warpage of 6-inch SiC wafer. Crucible lid on the backside of SiC seed holder was designed to be movable during the growth process. Based on the warp value and mapping measurement of FWHM (Full width at half maximum) value in X-ray rocking curve, the crystal quality of SiC crystals grown with new hot-zone design was observed to be better than conventional design.

High Epitaxial Growth Rate of 4H-SiC Using Horizontal Hot-Wall CVD

2006 ◽  
Vol 527-529 ◽  
pp. 187-190 ◽  
Author(s):  
Rachael L. Myers-Ward ◽  
Y. Shishkin ◽  
Olof Kordina ◽  
I. Haselbarth ◽  
Stephen E. Saddow
Keyword(s):  
Growth Rate ◽  
Epitaxial Growth ◽  
Growth Process ◽  
Structural Quality ◽  
Growth Time ◽  
Film Morphology ◽  
X Ray Diffraction ◽  
Rocking Curve ◽  
X Ray

A 4H-SiC epitaxial growth process has been developed in a horizontal hot-wall CVD reactor using a standard chemistry of silane-propane-hydrogen, producing repeatable growth rates up to 32 μm/h. The growth rate was studied as a function of pressure, silane flow rate, and growth time. The structural quality of the films was determined by X-ray diffraction. A 65 μm thick epitaxial layer was grown at the 32 μm/h rate, resulting in a smooth, specular film morphology with occasional carrot-like and triangular defects. The film proved to be of high structural quality with an X-ray rocking curve FWHM value of the (0004) peak of 11 arcseconds.

scholarly journals Characterization of a 4-inch GaN wafer by X-ray diffraction topography

CrystEngComm ◽  
2018 ◽  
Vol 20 (48) ◽  
pp. 7761-7765 ◽  
Author(s):  
Jaemyung Kim ◽  
Okkyun Seo ◽  
Chulho Song ◽  
Yanna Chen ◽  
Satoshi Hiroi ◽  
...  
Keyword(s):  
Crystal Quality ◽  
X Ray Diffraction ◽  
X Ray

We have investigated the crystal quality of a 4-inch GaN wafer by X-ray diffraction topography.

Growth and Characterization of LaFeO3 Crystals

2014 ◽  
Vol 602-603 ◽  
pp. 27-31 ◽  
Author(s):  
Wei Liang Liu ◽  
Xiao Jun Zeng ◽  
Shuo Qi Liu ◽  
Yan Feng Zhu ◽  
An Hua Wu
Keyword(s):  
Thermal Conductivity ◽  
Polished Surface ◽  
Floating Zone ◽  
Zone Method ◽  
Rocking Curve ◽  
Floating Zone Method ◽  
X Ray ◽  
Variation Range

The LaFeO3 polycrystalline feed rod was prepared by sintering La2O3 and Fe2O3 powder at 1400 °C for 24 h. The LaFeO3 crystal was grown by the floating zone method. The crystal preferred to crystallize along <100> direction. The X-ray rocking curve of the (100) crystal plane has a FWHM of 26 arcsec, confirming the high crystal quality of the sample. Some voids were observed on the polished surface. The thermal properties of LaFeO3 crystal during 298~773 K were tested. The specific heat of LaFeO3 crystal variation range was 0.58~0.76 J/(g·K), The thermal diffusivity of LaFeO3 crystal variation range was 3.47~0.85 mm2/s, The thermal conductivity of LaFeO3 crystal variation range was 13.10~4.21 W/(m·K).

Characterization of Natural and Synthesized FeTiO3 Crystals With RBS/PIXE/XRD

1997 ◽  
Vol 07 (03n04) ◽  
pp. 265-275
Author(s):  
R. Q. Zhang ◽  
S. Yamamoto ◽  
Z. N. Dai ◽  
K. Narumi ◽  
A. Miyashita ◽  
...  
Keyword(s):  
Single Crystals ◽  
Ion Beam ◽  
Pressure Control ◽  
Floating Zone ◽  
X Ray Diffraction ◽  
X Ray ◽  
Beam Analysis ◽  
Ppm Level

Natural FeTiO 3 (illuminate) and synthesized FeTiO 3, single crystals were characterized by Rutherford backscattering spectroscopy combined with channeling technique and particle-induced x-ray emission (RBS-C and PIXE). The results obtained by the ion beam analysis were supplemented by the x-ray diffraction analysis to identify the crystallographic phase. Oriented single crystals of synthesized FeTiO 3 were grown under the pressure control of CO 2 and H 2 mixture gas using a single-crystal floating zone technique. The crystal quality of synthesized FeTiO 3 single crystals could be improved by the thermal treatment but the exact pressure control is needed to avoid the precipitation of Fe 2 O 3 even during the annealing procedure. Natural FeTiO 3 contains several kinds of impurities such as Mn , Mg , Na and Si . The synthesized samples contain Al , Si and Na which are around 100 ppm level as impurities. The PBS-C results of the natural sample imply that Mn impurities occupy the Fe sublattice in FeTiO 3 or in mixed phase between ilmenite and hematite.

Characterization of WC-Co Coatings Using HP/HVOF Process

1996 ◽  
Author(s):  
S.Y. Hwang ◽  
B.G. Seong ◽  
M.C. Kim
Keyword(s):  
Wear Resistance ◽  
X Ray Diffraction ◽  
High Carbon ◽  
Properties Of Coatings ◽  
X Ray ◽  
Hvof Process ◽  
Number Of Passes ◽  
Oxygen Fuel

Abstract To maintain surface roughness of process rolls in cold rolling steel plants, WC-Co coatings have been known to be effective ones. In this study, a high pressure/high velocity oxygen fuel (HP/HVOF) process was used to obtain WC-Co coatings. To get the best quality of coatings, WC-Co coatings are sprayed with numerous powders made by various processes. These powders include agglomerated sintered powders, fused-crushed powders, extra high carbon WC-Co powders and (W2C, WC)-Co powders. After spraying, properties of coatings such as hardness, wear resistance. X-ray diffraction, and microstructures were analyzed. For coatings produced by agglomerated-sintered powders, hardness of the coating increased as power levels and the number of passes were increased. In case of the coatings produced by fused-crushed powders, a very low deposition rate was obtained due to a low flowablity of the powders. In addition, the WC-Co coatings sprayed with extra carbon content of WC-Co did not show improved hardness and wear resistance. Also, some decomposition of WC was observed in the coating. Finally, the coatings produced by (W2C, WC)-Co powders produced higher hardness and lower wear resistance coating.

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