Ion Beam Induced Epitaxial Crystallization of Single Crystalline 6H-SiC

1993 ◽  
Vol 321 ◽  
Author(s):  
V. Heera ◽  
R. Kögler ◽  
W. Skorupa ◽  
E. Glaser
Keyword(s):  
Surface Layer ◽  
Ion Irradiation ◽  
Ion Beam ◽  
Amorphous Layer ◽  
Single Crystalline ◽  
Epitaxial Crystallization ◽  
Amorphous Surface ◽  
20 Nm ◽  
First Time

ABSTRACTFor the first time, ion beam induced epitaxial crystallization (IBIEC) has been found in SiC. The effect of 300 keV Si+ irradiation through an amorphous surface layer in single crystalline 6H-SiC at 477+5°C has been investigated by RBS/C and XTEM. A shrinkage of the amorphous layer was found after ion irradiation at this temperature which is caused by both an ion dose independent thermal regrowth of about 20 nm and an additional ion beam induced epitaxial crystallization with a rate of about 1.5 nm/ 1016 cm−2.

Ion Beam Induced Epitaxial Crystallization of Single Crystalline 6H-SiC

1993 ◽  
Vol 316 ◽  
Author(s):  
V. Heera ◽  
R. Kögler ◽  
W. Skorupa ◽  
E. Glaser
Keyword(s):  
Surface Layer ◽  
Ion Irradiation ◽  
Ion Beam ◽  
Amorphous Layer ◽  
Single Crystalline ◽  
Epitaxial Crystallization ◽  
Amorphous Surface ◽  
20 Nm ◽  
First Time

ABSTRACTFor the first time, ion beam induced epitaxial crystallization (IBIEC) has been found in SiC. The effect of 300 keV Si+ irradiation through an amorphous surface layer in single crystalline 6H-SiC at 477±5°C has been investigated by RBS/C and XTEM. A shrinkage of the amorphous layer was found after ion irradiation at this temperature which is caused by both an ion dose independent thermal regrowth of about 20 nm and an additional ion beam induced epitaxial crystallization with a rate of about 1.5 nm/ 1016 cm-2.

Ion-Beam Induced Epitaxial Crystallization of NiSi2 And CoSi2

1989 ◽  
Vol 157 ◽  
Author(s):  
M.C. Ridgway ◽  
R.G. Elliman ◽  
J.S. Williams
Keyword(s):  
Ion Irradiation ◽  
Ion Beam ◽  
Activation Energies ◽  
Layer By Layer ◽  
Surface Layers ◽  
Epitaxial Crystallization ◽  
Si Substrates ◽  
Amorphous Surface

ABSTRACTIon—beam induced epitaxial crystallization (IBIEC) of amorphous N1Si2 and CoSi2 layers is demonstrated. Epitaxial metal suicide layers on (111) Si substrates were implanted with 40 keV Si ions to form amorphous surface layers. IBIEC of amorphous NiSi2 and CoSi2 layers was induced at 13—74°C with 1.5 MeV Ne ion irradiation and proceeded in a layer—by—layer manner from the original amorphous/crystalline interface with activation energies of 0.26 ± 0.07 and 0.21 ± 0.06 eV for N1Si2 and CoSi2, respectively.

Ion Beam Induced Amorphization and Crystallization Processes in Silicon and GaAs

1986 ◽  
Vol 74 ◽  
Author(s):  
R. G. Elliman ◽  
J. S. Williams ◽  
S. T. Johnson ◽  
E. Nygren
Keyword(s):  
Crystal Growth ◽  
Ion Irradiation ◽  
Ion Beam ◽  
Amorphous Layer ◽  
Poor Quality ◽  
Layer By Layer ◽  
Epitaxial Crystallization ◽  
Non Linear ◽  
Thickness Layer

AbstractThin amorphous layers in crystalline Si and GaAs substates have been irradiated at selected temperatures with 1.5 MeV Ne+ ions to induce either epitaxial crystallization or amorphization. In Si, such irradiation can induce complete epitaxial crystallization of a 1000 A surface amorphous layer for temperatures typically >200°C whereas, at significantly lower temperatures, layer-by-layer amorphization results. Although epitaxial crystallization can also be stimulated in GaAs by ion irradiation at temperatures >65°C, the process is non-linear with ion dose and results in poor quality crystal growth for amorphous layers greater than a few hundred Angstroms in thickness. Layer-by-layer amorphization has not been observed in GaAs.

Ion-Irradiation Study of the “Exotic” Mineral Neptunite: LiNa2K(Fe,Mg,Mn)2Ti2Si8O24

1990 ◽  
Vol 201 ◽  
Author(s):  
Ray K. Eby ◽  
L. M. Wang ◽  
G. W. Arnold ◽  
R. C. Ewing
Keyword(s):  
Surface Layer ◽  
Room Temperature ◽  
Ion Irradiation ◽  
Amorphous Layer ◽  
Narrow Region ◽  
Transmission Electron ◽  
Room Temperature Aging ◽  
Transparent Region ◽  
Amorphous Surface ◽  
Temperature Aging

AbstractSingle crystals of the silicate neptunite were irradiated with 600 keV Ar2+ and 1.5 MeV Kr+ and analysed by transmission electron microscopy. Amorphization was observed in a surface layer several hundred angstroms thick following Ar2+ irradiations up to 5.0×l013 Ar/cm2, yet the Ar2+ ions travelled an average of 1/2 μm in depth. The microstructure of the amorphous surface layer depends on the ion fluence, but the amorphous layer thickness remained constant. At the highest fluence, a narrow region below the amorphous layer shows a brittle-to-ductile strain transition, due to tensional volume-expansion of the adjacent ductile amorphous layer. With 1.5 MeV Kr1+, amorphization of the electron transparent region was completed after a fluence of 1.7×l014 Kr+/cm2, and no further damage was observed up to 5.1×1015 Kr+/cm2. However, following a low fluence of 2.0×1011 Kr+/cm2, a single crystal of neptunite became a polycrystalline aggregate (grain size 10 nm) within 7 days of room temperature aging.

Amortization and Recrystallization of 6H-SiC by ion Beam Irradiation

1994 ◽  
Vol 339 ◽  
Author(s):  
V. Heera ◽  
R. Kögler ◽  
W. Skorupa ◽  
J. Stoemenos
Keyword(s):  
Ion Irradiation ◽  
Ion Beam ◽  
Surface Region ◽  
Ion Beam Irradiation ◽  
Surface Layers ◽  
Near Surface ◽  
Transmission Electron ◽  
Amorphous Surface ◽  
Amorphous Sic

ABSTRACTThe evolution of the damage in the near surface region of single crystalline 6H-SiC generated by 200 keV Ge+ ion implantation at room temperature (RT) was investigated by Rutherford backscattering spectroscopy/chanelling (RBS/C). The threshold dose for amorphization was found to be about 3 · 1014 cm-2, Amorphous surface layers produced with Ge+ ion doses above the threshold were partly annealed by 300 keV Si+ ion beam induced epitaxial crystallization (IBIEC) at a relatively low temperature of 480°C For comparison, temperatures of at least 1450°C are necessary to recrystallize amorphous SiC layers without assisting ion irradiation. The structure and quality of both the amorphous and recrystallized layers were characterized by cross-section transmission electron microscopy (XTEM). Density changes of SiC due to amorphization were measured by step height measurements.

Epitaxial Crystallization of Amorphous Silicon Layers under Ion Irradiation: Orientation Dependence

1987 ◽  
Vol 93 ◽  
Author(s):  
D. M. Maher ◽  
R. G. Elliman ◽  
J. Linnros ◽  
J. S. Williams ◽  
R. V. Knoell ◽  
...  
Keyword(s):  
Amorphous Silicon ◽  
Solid Phase ◽  
Ion Irradiation ◽  
Ion Beam ◽  
Orientation Dependence ◽  
Epitaxial Crystallization ◽  
Beam Experiment ◽  
Interfacial Defects ◽  
Behavior Supports ◽  
Orientation Dependency

ABSTRACTIon-beam induced epitaxial crystallization of thin amorphous silicon layers at {100} and {110} crystalline/amorphous interfaces exhibits no orientation dependencies, whereas at a {111} crystalline/amorphous interface a weak orientation dependency relative to thermal-induced epitaxial crystallization is observed. This behavior supports an interpretation in which the thermal crystallization process is dominated by the need to form interfacial defects and/or growth sites and in the ion-beam experiment this formation process ocurrs athermally. It is thought that the observed orientation dependent regrowth on a {111} substrate relative to a {100} (or {110}) substrate is associated with the special correlated atomic sequencing which is believed to control solid-phase epitaxial crystallization at a {111) crystalline/amorphous interface.

Microstructures of Stainless Steels Exhibiting Reduced Friction and Wear After Implantation with Ti and C

1983 ◽  
Vol 27 ◽  
Author(s):  
D. M. Follstaedt ◽  
F. G. Yost ◽  
L.E. Pope
Keyword(s):  
Mechanical Properties ◽  
Stainless Steel ◽  
Surface Layer ◽  
Stainless Steels ◽  
Friction And Wear ◽  
Amorphous Layer ◽  
The Other ◽  
Pin On Disc ◽  
Amorphous Surface ◽  
Type 304

ABSTRACTImplantation of Ti and C into stainless steel discs of Types 304, 15–5 PH, Nitronic 60 and 440C has previously been reported to reduce wear depths by up to ∼ 85% and friction by ∼ 50% in unlubricated pin-on-disc tests. Our earlier studies relating microstructure to friction and wear results in Type 304 are first summarized; these indicate that the improvements in the surface mechanical properties are due to an amorphous surface layer, similar to the amorphous layer observed in pure Fe implanted with Ti and C. We have now examined the other three implanted steels and found similar amorphous layers. These results strongly suggest that the amorphous surface alloy is responsible for reduced friction and wear in all the steels.

The Competition between Ion Beam Induced Epitaxial Crystallization and Amorphization in Silicon: The Role of the Divacancy

1986 ◽  
Vol 74 ◽  
Author(s):  
J. Linnros ◽  
R. G. Elliman ◽  
W. L. Brown
Keyword(s):  
Activation Energy ◽  
Dose Rate ◽  
Dynamic Equilibrium ◽  
Ion Beam ◽  
Amorphous Layer ◽  
Linear Displacement ◽  
Epitaxial Crystallization ◽  
Critical Dose ◽  
Ion Species

AbstractThe transition from ion induced epitaxial crystallization to planar amorphization of a preexisting amorphous layer in silicon has been investigated. The conditions for dynamic equilibrium at the transition were determined for different ion species as a function of dose rate and temperature. The critical dose rate for equilibrium varies exponentially with 1/T, exhibiting an activation energy of ∼1.2 eV. Furthermore, for different ions, the critical dose rate is inversely proportional to the square of the linear displacement density created by individual ions. This second order defect production process and the activation energy, which is characteristic of divacancy dissociation, suggest that the accumulation of divacancies at the amorphous/crystalline interface controls the balance between crystallization and amorphization.

Improved Focused Ion Beam Target Preparation of (S)TEM Specimen—A Method for Obtaining Ultrathin Lamellae

2012 ◽  
Vol 18 (2) ◽  
pp. 379-384 ◽  
Author(s):  
Lorenz Lechner ◽  
Johannes Biskupek ◽  
Ute Kaiser
Keyword(s):  
High Resolution ◽  
Focused Ion Beam ◽  
Ion Beam ◽  
Amorphous Layer ◽  
Large Area ◽  
Preparation Methods ◽  
Target Preparation ◽  
Scanning Transmission ◽  
High Resolution Tem ◽  
20 Nm

AbstractSpecimen quality is vital to (scanning) transmission electron microscopy (TEM) investigations. In particular, thin specimens are required to obtain excellent high-resolution TEM images. Conventional focused ion beam (FIB) preparation methods cannot be employed to reliably create high quality specimens much thinner than 20 nm. We have developed a method forin situtarget preparation of ultrathin TEM lamellae by FIB milling. With this method we are able to routinely obtain large area lamellae with coplanar faces, thinner than 10 nm. The resulting specimens are suitable for low kV TEM as well as scanning TEM. We have demonstrated atomic resolution byCs-corrected high-resolution TEM at 20 kV on a FIB milled Si specimen only 4 nm thick; its amorphous layer measuring less than 1 nm in total.

Evolution of Semiconductor Thin Film and Surface Microstructure During Ion Bombardment

1990 ◽  
Vol 202 ◽  
Author(s):  
H. A. Atwater
Keyword(s):  
Thin Films ◽  
Ion Irradiation ◽  
Ion Beam ◽  
Amorphous Layer ◽  
Misfit Strain ◽  
Crystal Nucleation ◽  
Microstructural Development ◽  
Complete Suppression ◽  
Semiconductor Films ◽  
Interface Motion

ABSTRACTDefects created by ion irradiation can enable new modes of microstructural development at interfaces and surfaces in semiconductor thin films. Two examples are described. First, novel kinetic paths for microstructural evolution via MeV ion beam modification of amorphous-crystal interface motion in Si are discussed. At intermediate temperatures, amorphous layer formation is initiated at interfaces such as surfaces and grain boundaries in polycrystalline Si. Irradiation at higher temperatures during the early stages of Si crystallization leads to a significant enhancement of the crystal nucleation rate, while nearly complete suppression of crystal nucleation during crystal growth can be achieved by a cyclic irradiation-induced amorphization and thermal growth process. Second, a new development in misfit strain accommodation in epitaxial semiconductor films is described in which ion-induced injection of point defect complexes can produce coherent, uniformly strained epitaxial thin films. Measurement of strain in epitaxial films can be used to distinguish between surface and sub-surface atomic displacements generated by a low energy ion beam.

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