Creation of pure non-crystalline diamond nanostructures via room temperature ion irradiation and subsequent thermal annealing

AbstractThe influence of the irradiation temperature Tirr on the development of disordered zones produced at displacement cascades in Ni3A1 by heavy-ion irradiation with 50 keV Ta+ and 300 keV Ni+ ions has been investigated. The normalised number density (yield) of disordered zones for 300 keV Ni+ irradiation showed a sharp fall between Tirr= 373 K and 573 K. For 50 keV Ni+ irradiation there was a similar fall between 573 K and 673 K. The mean diameters of the disordered zones produced by 300 keV Ni+ ions decreased by about 2 nm between room temperature and 573 K, and there was a tendency for larger zones to become more regular in shape. For 50 keV Ta+ ions, a similar trend was observed between 573 K and 873 K. An annealing experiment confirmed that disordered zones produced at lower temperatures were stable up to a temperature of about 673 K, showing that these trends cannot be due to thermal annealing of disordered zones. The experimental results are consistent with an increased tendency for reordering at the peripheries of disordered zones, due to the increased lifetimes of thermal spikes at higher irradiation temperatures.

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Structural Variation of Transition Metal - Fullerene Thin Films Modified by Thermal Annealing and Ion or Laser Beam Bombardment

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.463-464.1387 ◽

2012 ◽

Vol 463-464 ◽

pp. 1387-1391 ◽

Cited By ~ 1

Author(s):

Jiri Vacik ◽

Vasyl Lavrentev ◽

Pavel Horak ◽

R. Fajgar

Keyword(s):

Thin Films ◽

Transition Metal ◽

Thermal Annealing ◽

Large Scale ◽

Room Temperature ◽

Structural Variation ◽

Ion Irradiation ◽

Strong Impact ◽

Hybrid Films ◽

Structural Morphology

In this paper, we have inspected the structural morphology of novel composite materials - transition metal (TM) (Ni, Ti) / fullerene (C60) thin films, prepared at room temperature (RT) or 500°C, and modified by ion-irradiation and/or thermal annealing. The hybrid films were synthesized by alternative or simultaneous deposition of the immiscible TM and C60 phases. As deposited (at RT) the hybrid systems were thermodynamically unstable and the internal stress induced lengthy phase separation. Co-deposition at 500°C resulted in the formation of a large-scale pattern structure. By high temperature annealing of the multilayer’s a new morphology could be synthesized. In addition, high-fluence ion-irradiation induces C60 fragmentation that has a strong impact on the final shaping of the resulted morphology.

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Rapid Thermal Annealing of InP Implanted with Group IV Eleients

MRS Proceedings ◽

10.1557/proc-300-351 ◽

1993 ◽

Vol 300 ◽

Author(s):

M.C. Ridgway ◽

P Kringhoj

Keyword(s):

Thermal Annealing ◽

Rapid Thermal Annealing ◽

Carrier Mobility ◽

Annealing Temperature ◽

Group Iv ◽

Electrical Activation ◽

Temperature Range ◽

Group Iv Elements

ABSTRACTElectrical activation and carrier mobility have been studied as a function of ion dose and annealing temperature for InP implanted with Group IV elements (Si, Ge and Sn). In general, electrical activation increases with decreasing ion dose and/or increasing annealing temperature. Si and Sn exhibit comparable activation and mobility, superior to that of Ge, over the ion dose and temperature range examined. The relative influences of implantation-induced non-stoichiometry and the amphoteric behaviour of the group IV elements have been investigated. For the latter, the amphoteric behavior of Ge > Si > Sn.

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Diamond-Based Field-Emission Displays

MRS Bulletin ◽

10.1557/s0883769400036149 ◽

1996 ◽

Vol 21 (3) ◽

pp. 59-64 ◽

Cited By ~ 118

Author(s):

James E. Jaskie

Keyword(s):

Lattice Structure ◽

Group Iv ◽

Film Deposition ◽

Crystalline Lattice ◽

Natural State ◽

Synthetic Diamonds ◽

Thermally Conductive ◽

The 1950S ◽

Group Iv Elements ◽

Silicon And Germanium

Diamond has existed in the natural state for thousands of years. It was mainly used as a jewel for its optical brilliance and for its hardness. In the 1950s methods were developed to fabricate synthetic diamonds commercially. This greatly increased diamond's industrial use, mostly for grinding and lapping applications. Diamond is a crystalline form of carbon, a group-IV element in the periodic table. Silicon and germanium are also Group-IV elements and also have the same crystalline lattice structure as diamond. Hence there has been theoretical interest in diamond's electronic properties since the beginning of the semiconductor age. However the cost and poor crystalline quality of both natural and synthetic diamond have precluded any real industrial interest in diamond as an electronic material. Methods of low-temperature and low-pressure diamond-film deposition, developed initially by the Russians in the 1950s and 1960s (and thence by the Japanese, and eventually by others) has made it possible to use this exotic material as an electronic substrate.Diamond, in single-crystalline, polycrystalline, and diamondlike carbon (DLC) forms, is a material with many unusual properties. It is the hardest naturally occurring material, the most thermally conductive, and the most transparent. It also has the slickness of Teflon. In regard to many physical properties, it is at the extreme end of the scale. One of the more unusual and important properties that it possesses is its presentation of a rather small barrier to the emission of electrons into a vacuum.

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Thermal Annealing of Solid Kr Precipitates in Ni

MRS Proceedings ◽

10.1557/proc-157-277 ◽

1989 ◽

Vol 157 ◽

Cited By ~ 1

Author(s):

R. C. Birtcher ◽

J. Rest ◽

D. S. Bergstrom

Keyword(s):

Size Distribution ◽

Thermal Annealing ◽

Room Temperature ◽

Precipitate Size ◽

Rate Theory ◽

Bimodal Size Distribution ◽

Transmission Electron ◽

Precipitate Size Distribution ◽

Subsequent Thermal Annealing ◽

Annealing Experiments

ABSTRACTAfter implantation into Ni at room temperature, Kr condenses under high pressure as an fee solid aligned with the Ni lattice. Evolution of these precipitates during subsequent thermal annealing to a temperature of 650 C has been followed with transmission electron microscopy and modeled with rate theory.Room temperature implantation results in a monomodal size distribution of small solid Kr precipitates. When Kr is implanted into Ni at 500 C, some precipitates grow to larger sizes, and the precipitate size distribution becomes bimodal. Annealing to temperatures below 600 C after room temperature implantation produces a bimodal size distribution consisting of small solid Kr precipitates and large Kr bubbles. Annealing above 600 C leads to more complete precipitate motion and coalescence that eliminates all small precipitates and results in a monomodal size distribution of large faceted bubbles.Rate-theory modelling of Kr implantation into Ni at 500 C suggests that small solid Kr precipitates are immobile and that Kr melting is required for precipitate mobility. Similar calculations for thermal annealing experiments show that the bubble size distribution becomes bimodal when only a small fraction of the small precipitates melt and become mobile during annealing, while the size distribution remains monomodal when all precipitates become mobile after Kr melting at higher temperatures.

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The Effect Of Ion-Implantation Induced Defects On Strain Relaxation In GexSi1−x/Si Heterostuctures

MRS Proceedings ◽

10.1557/proc-442-367 ◽

1996 ◽

Vol 442 ◽

Cited By ~ 3

Author(s):

J. M. Glasko ◽

J. Zou ◽

D. J. H. Cockayne ◽

J. Fitz Gerald ◽

P. KringhøJ ◽

...

Keyword(s):

Thermal Annealing ◽

Ion Irradiation ◽

Strain Relaxation ◽

High Energy ◽

Alloy Layer ◽

Misfit Dislocations ◽

Thermally Induced ◽

Energy Irradiation ◽

Induced Defects ◽

Subsequent Thermal Annealing

AbstractThis study examined the effect of ion irradiation and subsequent thermal annealing on GeSi/Si strained-layer heterostructures. Comparison between samples irradiated at 253°C with low energy (23 keV) and high energy (1.0 MeV) Si ions showed that damage within the alloy layer increases the strain whereas irradiation through the layer/substrate interface decreases the strain. Loop-like defects formed at the GeSi/Si interface during high energy irradiation and interacting segments of these defects were shown to have edge character with Burgers vector a/2<110>. These defects are believed responsible for the observed strain relief. Irradiation was also shown to affect strain relaxation kinetics and defect morphologies during subsequent thermal annealing. For example, after annealing to 900°C, un-irradiated material contained thermally-induced misfit dislocations, while ion-irradiated samples showed no such dislocations.

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Investigation of irradiation-induced nucleation processes in silicon and germanium

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100137495 ◽

1995 ◽

Vol 53 ◽

pp. 224-225

Author(s):

Harry A. Atwater ◽

C.M. Yang ◽

K.V. Shcheglov

Keyword(s):

Room Temperature ◽

Crystal Size ◽

Initial Distribution ◽

Engineering Control ◽

Size Evolution ◽

Silicon And Germanium ◽

Ge Quantum Dot ◽

And Control ◽

Germanium Quantum Dots ◽

Kinetics Of

Studies of the initial stages of nucleation of silicon and germanium have yielded insights that point the way to achievement of engineering control over crystal size evolution at the nanometer scale. In addition to their importance in understanding fundamental issues in nucleation, these studies are relevant to efforts to (i) control the size distributions of silicon and germanium “quantum dots𠇍, which will in turn enable control of the optical properties of these materials, (ii) and control the kinetics of crystallization of amorphous silicon and germanium films on amorphous insulating substrates so as to, e.g., produce crystalline grains of essentially arbitrary size.Ge quantum dot nanocrystals with average sizes between 2 nm and 9 nm were formed by room temperature ion implantation into SiO2, followed by precipitation during thermal anneals at temperatures between 30°C and 1200°C[1]. Surprisingly, it was found that Ge nanocrystal nucleation occurs at room temperature as shown in Fig. 1, and that subsequent microstructural evolution occurred via coarsening of the initial distribution.

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