Surface Behavior and Lattice Relaxation of SiGe/Si Strained Epitaxial Heterostructures

1992 ◽  
Vol 280 ◽  
Author(s):  
Kevin H. Chang ◽  
H. Ming Liaw
Keyword(s):  
Surface Morphology ◽  
Epitaxial Growth ◽  
Lattice Relaxation ◽  
Dislocation Motion ◽  
Surface Behavior ◽  
Dopant Level ◽  
Epitaxial Heterostructures ◽  
Glissile Dislocation ◽  
Boron Dopant ◽  
Strained Sige

ABSTRACTThe correlation between the surface morphology and the lattice relaxation in strained SiGe/Si heteroepitaxy has been studied. It is found that the surface crosshateched pattern develops as the strained epilayer thickness increases. The effect of thermal annealing and boron dopant level has also been studied. The result suggests that the crosshatched morphology on the surface is constituted by surface slip steps of glissile dislocation motion in the strained epitaxial growth processing.

Control of the Surface Morphology on Low Off Angled 4H-SiC Homoepitaxal Growth

2009 ◽  
Vol 615-617 ◽  
pp. 113-116 ◽  
Author(s):  
Kazutoshi Kojima ◽  
Hajime Okumura ◽  
Kazuo Arai
Keyword(s):  
Surface Morphology ◽  
Epitaxial Growth ◽  
Epitaxial Layer ◽  
Flow Rate ◽  
Growth Conditions ◽  
Layer Surface ◽  
Specular Surface ◽  
Homoepitaxial Growth ◽  
Angle Difference ◽  
The Face

We have carried out detailed investigations on the influence of the growth conditions and the wafer off angle on the surface morphology of low off angle homoepitaxial growth. We found triangular features to be also serious problems on a 4 degree off 4H-SiC Si-face epitaxial layer surface. The control of the C/Si ratio by controlling the SiH4 flow rate is effective in suppressing the triangular features on 4 degree off Si-face homoepitaxial layer. As regards epitaxial growth on a vicinal off-axis substrate, the small off angle difference of a tenth part of a degree has an influence on the surface morphology of the epitaxial layer. This tendency depends on the face polarity and a C-face can be obtained that has a specular surface with a lower vicinal off angle than a Si-face. By controlling this off angle, a specular surface morphology without a bunched step structure could be obtained on a vicinal off angle 4H-SiC Si-face.

Nuclear Spin Relaxation Investigations on the Influence of Impurities and Temperature on the Mean Free Path of Mobile Dislocations in Nacl

1980 ◽  
Vol 3 ◽  
Author(s):  
W. H. M. Alsem ◽  
J. Th. ◽  
M. De Hosson ◽  
H. Tamler ◽  
H. J. HackelÖEr ◽  
...  
Keyword(s):  
Free Path ◽  
Lattice Relaxation ◽  
Mean Free Path ◽  
Dislocation Motion ◽  
Spin Lattice Relaxation ◽  
Spin Lattice ◽  
Activation Rate ◽  
The Mean ◽  
Influence Of Impurities

ABSTRACTDislocation motion in alkali halide single crystals is strongly impeded by the presence of impurities, apart from obstacles built by the forest dislocations. The mean free path L of stepwise moving dislocations is measured by determination of the spin-lattice relaxation rate 1/T1ρ as a function of the strain rate έ, varying the content of impurities and the temperature. The latter influences the distribution of the point defects and the activation rate of dislocations before obstacles, while the former merely shorten L, thereby raising 1/T1ρ.

4H-SiC Homoepitaxial Growth on Vicinal-Off Angled Si-Face Substrate

2010 ◽  
Vol 645-648 ◽  
pp. 99-102 ◽  
Author(s):  
Kazutoshi Kojima ◽  
Sachiko Ito ◽  
Junji Senzaki ◽  
Hajime Okumura
Keyword(s):  
Surface Morphology ◽  
Epitaxial Growth ◽  
Growth Temperature ◽  
Growth Conditions ◽  
Step Bunching ◽  
Homoepitaxial Growth ◽  
Blocking Voltage ◽  
Basal Plane Dislocation ◽  
Epilayer Surface

We have carried out detailed investigations of 4H-SiC homoepitaxial growth on vicinal off-angled Si-face substrates. We found that the surface morphology of the substrate just after in-situ H2 etching was also affected by the value of the vicinal-off angle. Growth conditions consisting of a low C/Si ratio and a low growth temperature were effective in suppressing macro step bunching at the grown epilayer surface. We also demonstrated epitaxial growth without step bunching on a 2-inch 4H-SiC Si-face substrate with a vicinal off angle of 0.79o. Ni Schottky barrier diodes fabricated on an as-grown epilayer had a blocking voltage above 1000V and a leakage current of less than 5x10-7A/cm2. We also investigated the propagation of basal plane dislocation from the vicinal off angled substrate into the epitaxial layer.

Homoepitaxial Growth on Si-Face (0001) On-Axis 4H-SiC Substrates

2019 ◽  
Vol 954 ◽  
pp. 31-34
Author(s):  
Guo Guo Yan ◽  
Xing Fang Liu ◽  
Feng Zhang ◽  
Zhan Wei Shen ◽  
Wan Shun Zhao ◽  
...  
Keyword(s):  
Growth Rate ◽  
Surface Morphology ◽  
Epitaxial Growth ◽  
Growth Temperature ◽  
Epitaxial Layers ◽  
Homoepitaxial Growth ◽  
Influence Mechanism

Homoepitaxial growths of 4H-SiC were performed on Si-face (0001) on-axis substrates in a SiH4-C2H4-H2-HCl system by using our home-made vertical hot wall CVD reactor. The influence mechanism of the growth temperature and C/Si ratio on the morphology and growth rate was studied. It is found that the steps in the epilayer become more clear with the increasing temperatures. The result indicates that the C/Si ratio window of on-axis epitaxial growth is very narrow. Only when the C/Si ratio was 1.2, a slightly improved surface morphology can be achieved. The results indicate that 4H-SiC epitaxial layers were obtained on on-axis substrates and the films were highly-oriented 4H-SiC.

Interdiffusion in strained Si/strained SiGe epitaxial heterostructures

2006 ◽  
Vol 22 (1) ◽  
pp. S55-S58 ◽  
Author(s):  
Guangrui (Maggie) Xia ◽  
Michael Canonico ◽  
Judy L Hoyt
Keyword(s):  
Strained Si ◽  
Epitaxial Heterostructures ◽  
Strained Sige

Improved Meltback Procedures for Liquid-Phase-Epitaxial Growth of Planar and Buried Heterostructures

1982 ◽  
Vol 14 ◽  
Author(s):  
B. H. Chin ◽  
A. K. Chin ◽  
M. A. Digiuseppe ◽  
I. A. Lourenco ◽  
I. Camlibel
Keyword(s):  
Liquid Phase ◽  
Surface Morphology ◽  
Indium Phosphide ◽  
Epitaxial Growth ◽  
Flat Surface ◽  
Device Performance ◽  
Buried Heterostructure ◽  
Liquid Phase Epitaxial Growth ◽  
Scattering Light ◽  
Heterostructure Devices

ABSTRACTIn the liquid phase epitaxy on indium phosphide, the substrate,just prior to the growth of the first epitaxial layer, is commonly etched back with an indium melt to remove any thermallydegraded surface and to ensure uniform and consistent wetting.This procedure, however, often produces defects which degrade both planar and buried heterostructure devices. For planar edgeemitters and lasers, the resulting rippled surface morphology degrades device performance by scattering light. For buried heterostructures, the meltback in the regrowth step leads to indium-rich inclusions. The effects of meltback on material quality are presented, and a new multiple meltback procedure which maintains flat surface morphology and eliminates inclusions is described.

Epitaxial TaC Films for the Selective Area Growth of SiC

2008 ◽  
Vol 600-603 ◽  
pp. 183-186 ◽  
Author(s):  
Kenneth A. Jones ◽  
T.S. Zheleva ◽  
R.D. Vispute ◽  
Shiva S. Hullavarad ◽  
M. Ervin ◽  
...  
Keyword(s):  
High Temperature ◽  
Surface Morphology ◽  
Epitaxial Growth ◽  
Lattice Parameter ◽  
Selective Area Growth ◽  
Recrystallization Process ◽  
High Temperature Annealing ◽  
Selective Area ◽  
Area Growth ◽  
Lattice Matched

At sufficiently high temperatures PLD deposited TaC films can be grown epitaxially on 4H-SiC (0001) substrates; at lower temperatures the films recrystallize and ball up forming a large number of pinholes. The growth temperature for epitaxy was found to be 1000°C, and it was facilitated by the epitaxial growth of a thin (2 nm) transition layer of hexagonal Ta2C. High temperature annealing produced changes in the surface morphology, caused grain growth, and created pin holes through a recrystallization process in the films deposited at the lower temperatures, while the films deposited at the higher temperatures remained virtually unchanged. Using TEM it is shown that the (0001) basal planes of the hexagonal 4H-SiC and Ta2C phases are aligned, and they were also parallel to the (111) plane in the cubic TaC with the [101] cubic direction being parallel to the hexagonal [2110] hexagonal direction. The Ta2C interlayer most likely is formed because its lattice parameter in the basel plane (3.103 Ǻ) is intermediate between that of the 4H-SiC (3.08 Ǻ) and the TaC (3.150 Ǻ). Given that Al.5Ga.5N is lattice matched to TaC, it could be an excellent substrate for the growth of GaN/AlGaN heterostructures.

Investigation of Epitaxially Grown PbO, TiO2 and ZrO2 as Bridge Layers for Integration of PZT on GaN by MBE

2006 ◽  
Vol 966 ◽  
Author(s):  
Xing Gu ◽  
Natalia Izyumskaya ◽  
Vataliy Avrutin ◽  
Hadis Morkoç
Keyword(s):  
Surface Morphology ◽  
Epitaxial Growth ◽  
Xrd Pattern ◽  
Growth Orientation

ABSTRACTEpitaxial growth of PbO, TiO2 and ZrO2 has been achieved on MOCVD grown GaN template using oxides MBE with a reactive H2O2 oxygen source. In situ RHEED was used to monitor the growth in-situ. AFM was used to characterize the surface morphology of the thin PbO and ZrO2, which show streaky, 2-D RHEED patterns. XRD pattern indicates that the growth orientation of these oxides are PbO [111]//GaN [0002], ZrO2[100]//GaN [0002] and TiO2[200]//GaN[0002].

Variations in Magnetic Hyperfine fields for Thin Epitaxial Heterostructures Of (110)Fe ON (111)Ag

1989 ◽  
Vol 151 ◽  
Author(s):  
C. J. Gutierrez ◽  
S. H. Mayer ◽  
Z. Q. Qiu ◽  
H. Tang ◽  
J. C. Walker
Keyword(s):  
Electron Diffraction ◽  
Epitaxial Growth ◽  
Growth Process ◽  
High Energy ◽  
Thin Layers ◽  
High Energy Electron ◽  
Hyperfine Fields ◽  
Iron Films ◽  
Magnetic Heterostructures ◽  
Epitaxial Heterostructures

ABSTRACTWe have made a study of magnetic heterostructures involving the epitaxial growth of (110)Fe on (111)Ag. The flatness and continuity of the films was verified by Reflection High Energy Electron Diffraction during the growth process. A series of structures were made with very thin intervening silver layers with thicker iron layers. The doping of appropriate layers by enriched Fe57 made it possible to examine the magnetic structure of the iron films as a function of depth. Preliminary results indicate that thin layers of silver sandwiched between two very thin Fe layers are able to transmit conduction electron polarization, resulting in iron behavior which resembles that of bulk iron. Implications of these results for understanding the nature of the magnetization of iron will be addressed in the following.

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