Modeling high temperature anneal hardening in Au submicron pillar by developing coupled dislocation glide-climb model

AbstractIt is well known that hydrogen plays a key role in p-type doping of GaN. It is believed that H passivates substitutional Mg during growth by forming a Mgs-N-Hi complex; in subsequent annealing, H is removed, resulting in p-type doping. Several open questions have remained, however, such as experimental evidence for other complexes involving Mg and H and difficulties in accounting for the relatively high-temperature anneal needed to remove H. We present first principles calculations in terms of which we show that the doping process is in fact significantly more complex. In particular, interstitial Mg plays a major role in limiting p-type doping. Overall, several substitutional/interstitial complexes form and can bind H, with vibrational frequencies that account for hitherto unidentified observed lines. We predict that these defects, which limit doping efficiency, can be eliminated by annealing in an atmosphere of H and N prior to the final anneal that removes H.

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Oxygen Precipitation in Conventional and Nitrogen Co-Doped Heavily Arsenic-Doped Czochralski Silicon Crystals: Oswald Ripening

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.156-158.275 ◽

2009 ◽

Vol 156-158 ◽

pp. 275-278

Author(s):

Xiang Yang Ma ◽

Yan Feng ◽

Yu Heng Zeng ◽

De Ren Yang

Keyword(s):

High Temperature ◽

Low Temperature ◽

Czochralski Silicon ◽

Silicon Crystals ◽

Oxygen Precipitation ◽

High Temperature Anneal ◽

Oxygen Precipitates ◽

Co Doped ◽

Oswald Ripening

Oxygen precipitation (OP) behaviors in conventional and nitrogen co-doped heavily arsenic-doped Czocharalski silicon crystals subjected to low-high two-step anneals of 650 oC/8 h + 1000 oC/4-256 h have been comparatively investigated. Due to the nitrogen enhanced nucleation of OP during the low temperature anneal, much higher density of oxygen precipitates generated in the nitrogen co-doped specimens. With the extension of high temperature anneal, Oswald ripening of OP in the nitrogen co-doped specimens preceded that in the conventional ones. Moreover, due to the Oswald ripening effect, the oxygen precipitates in the conventional specimens became larger with a wider range of sizes. While, the sizes of oxygen precipitates in the nitrogen co-doped specimens distributed in a much narrower range with respect to the conventional ones.

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Improvement of Minority Carrier Lifetime in Thick 4H-SiC Epi-layers by Multiple Thermal Oxidations and Anneals

MRS Proceedings ◽

10.1557/opl.2013.574 ◽

2013 ◽

Vol 1538 ◽

pp. 329-333 ◽

Cited By ~ 2

Author(s):

Lin Cheng ◽

Michael J. O’Loughlin ◽

Alexander V. Suvorov ◽

Edward R. Van Brunt ◽

Albert A. Burk ◽

...

Keyword(s):

High Temperature ◽

Carrier Lifetime ◽

Minority Carrier ◽

Minority Carrier Lifetime ◽

Power Devices ◽

Oxidation Treatment ◽

Temperature Oxidation ◽

Oxidation Step ◽

High Temperature Anneal ◽

Lifetime Enhancement

ABSTRACTThis paper details the development of a technique to improve the minority carrier lifetime of 4H-SiC thick (≥ 100 μm) n-type epitaxial layers through multiple thermal oxidations. A steady improvement in lifetime is seen with each oxidation step, improving from a starting ambipolar carrier lifetime of 1.09 µs to 11.2 µs after 4 oxidation steps and a high-temperature anneal. This multiple-oxidation lifetime enhancement technique is compared to a single high-temperature oxidation step, and a carbon implantation followed by a high-temperature anneal, which are traditional ways to achieve high ambipolar lifetime in 4H-SiC n-type epilayers. The multiple oxidation treatment resulted in a high minimum carrier lifetime of 6 µs, compared to < 2 µs for other treatments. The implications of lifetime enhancement to high-voltage/high-current 4H-SiC power devices are also discussed.

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Characterization of extrusion formation during high temperature anneal

2000 IEEE International Integrated Reliability Workshop Final Report (Cat. No.00TH8515) ◽

10.1109/irws.2000.911929 ◽

2002 ◽

Cited By ~ 1

Author(s):

J. Kelsey-Wynne ◽

F. Chen ◽

J. Furukawa ◽

T. Sullivan

Keyword(s):

High Temperature ◽

High Temperature Anneal

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Dynamic Behaviour of Dislocations in HF-Doped Ice Ih

Journal of Glaciology ◽

10.1017/s0022143000010352 ◽

1980 ◽

Vol 25 (91) ◽

pp. 133-150 ◽

Cited By ~ 7

Author(s):

J. Perez ◽

C. Maï ◽

J. Tatibouët ◽

R. Vassoille

Keyword(s):

Experimental Data ◽

Shear Stress ◽

High Temperature ◽

Internal Friction ◽

Dynamic Behaviour ◽

Dislocation Glide ◽

Linear Defects ◽

Doping Effects ◽

Crystalline Core ◽

Accumulation Effect

AbstractA model of dislocation glide in ice Ih was recently proposed. This model was developed on certain assumptions, namely that transitions occur through cooperative movements of H2O molecules in the non-crystalline core of dislocations. A relation between the velocityvdof linear defects and shear stressτor temperatureTis obtained. This relation shows thatvdvaries linearly withτat low values ofτand (or)Tbut varies more rapidly at higher stresses; this non-linearity is more pronounced the higher the temperature. Such an analysis is extended in order to take into account doping effects. The case of HF-doped ice is considered: it is shown that there is a strong accumulation effect of HF molecules in the dislocation cores, which induces an increase of the rate of transitions. The results are in agreement with experimental data concerning both the velocity of dislocations and high-temperature internal friction in HF-doped ice.

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High-temperature Deformation Kinetics of Gold at 473K to 773K

MRS Proceedings ◽

10.1557/proc-1137-ee04-10 ◽

2008 ◽

Vol 1137 ◽

Author(s):

Vineet Bhakhri ◽

Robert J. Klassen

Keyword(s):

High Temperature ◽

Cell Structure ◽

Dislocation Cell ◽

High Temperature Deformation ◽

Temperature Deformation ◽

Indentation Creep ◽

Creep Tests ◽

Dislocation Glide ◽

Deformation Kinetics ◽

Temperature Constant

AbstractHigh-temperature constant-force indentation creep tests of 200 seconds duration were performed on an annealed gold specimen at 473K to 773K, to investigate the dependence of the micro-/nano-indentation deformation kinetics upon indentation stress, temperature and time. The indent stress displayed a clear indentation size effect at 473 K. An analysis of the measured indentation creep rate, and its dependence upon temperature and stress, indicate that the strength of the deformation rate limiting obstacles increases with temperature. This is consistent with the expected temperature dependent evolution of the dislocation cell structure whose boundaries become the primary obstacles to dislocation glide.

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Non Destructive Determination of the Threading Dislocation Density of Smooth Simox Substrates using Atomic Force Microscopy

Microscopy and Microanalysis ◽

10.1017/s1431927600037934 ◽

2000 ◽

Vol 6 (S2) ◽

pp. 1088-1089

Author(s):

A. Domenicucci ◽

R. Murphy ◽

D. Sadanna ◽

S. Klepeis

Keyword(s):

Atomic Force Microscopy ◽

High Temperature ◽

Single Crystal Silicon ◽

Silicon Layer ◽

High Dose ◽

Threading Dislocation ◽

Crystal Silicon ◽

Force Microscopy ◽

Atomic Force ◽

High Temperature Anneal

Atomic force microscopy (AFM) has been used extensively in recent years to study the topographic nature of surfaces in the nanometer range. Its high resolution and ability to be automated have made it an indispensable tool in semiconductor fabrication. Traditionally, AFM has been used to monitor the surface roughness of substrates fabricated by separation by implanted oxygen (SIMOX) processes. It was during such monitoring that a novel use of AFM was uncovered.A SIMOX process requires two basic steps - a high dose oxygen ion implantation (1017 to 1018 cm-3) followed by a high temperature anneal (>1200°C). The result of these processes is to form a buried oxide layer which isolates a top single crystal silicon layer from the underlying substrate. Pairs of threading dislocations can form in the top silicon layer during the high temperature anneal as a result of damage caused during the high dose oxygen implant.

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Effect of high‐temperature anneal on interface states generation in stressed metal‐oxide‐semiconductor devices

Applied Physics Letters ◽

10.1063/1.104598 ◽

1991 ◽

Vol 58 (6) ◽

pp. 598-600 ◽

Cited By ~ 7

Author(s):

M. Berger ◽

E. Avni ◽

J. Shappir

Keyword(s):

High Temperature ◽

Metal Oxide ◽

Semiconductor Devices ◽

Interface States ◽

Metal Oxide Semiconductor ◽

Oxide Semiconductor ◽

High Temperature Anneal

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Analysis of Intragranular Misorientation Related to Deformation in an Al-Mg-Mn Alloy

Materials Science Forum ◽

10.4028/www.scientific.net/msf.495-497.1049 ◽

2005 ◽

Vol 495-497 ◽

pp. 1049-1054 ◽

Cited By ~ 22

Author(s):

Yoshimasa Takayama ◽

Jerzy A. Szpunar ◽

Hajime Kato

Keyword(s):

Electron Microscope ◽

High Temperature ◽

Room Temperature ◽

Electron Back Scatter Diffraction ◽

High Temperature Deformation ◽

Temperature Deformation ◽

Stored Energy ◽

Kernel Average Misorientation ◽

Dislocation Glide ◽

Scanning Electron

Intragranular misorientation reflects strain generated during deformation with dislocation glide. The SEM/EBSP (scanning electron microscope/ electron back scatter diffraction pattern) technique provides is “kernel average misorientation (KAM)” as the most appropriate quantity to evaluate the strain or the stored energy for a given point. The KAM is defined for a given point as the average misorientation of that point with all of its neighbors. In the present paper two analyses of the intragranular misorientation using the SEM/EBSP technique for a cyclic deformation at room temperature and a high temperature deformation in an Al-Mg-Mn alloy are reviewed.

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