Reactivation of Acceptors and Trapping of Hydrogen in GaN/InGaN Double Heterostructures

ABSTRACTThe apparent thermal stability of hydrogen passivated Mg acceptors in GaN is a function of the annealing ambient employed, with H2 leading to a reactivation temperature approximately 150°C higher than N2. The dissociation of Mg-H complexes and the loss of hydrogen from GaN are sequential processes, with reactivation occurring at ≤700°C for annealing under N2, while significant concentrations of hydrogen remain in the crystal even at 900°C in implanted samples. The hydrogen is gettered to regions of highest defect density such as the InGaN layer in a GaN/InGaN double heterostructure. The addition of an accelerating potential for 2H+ ions in the plasma did not greatly affect the deuterium profiles.

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Thermal Stability of Si/Si0.85Ge0.15/Si Modulation Doped Double Heterostructures

MRS Proceedings ◽

10.1557/proc-160-89 ◽

1989 ◽

Vol 160 ◽

Author(s):

P.J. Wang ◽

B.S. Meyerson ◽

P.M. Fahey ◽

F. LeGoues ◽

G.J. Scilla ◽

...

Keyword(s):

Thermal Stability ◽

High Vacuum ◽

Chemical Vapor ◽

Ultra High Vacuum ◽

Misfit Dislocations ◽

Two Dimensional ◽

Double Heterostructures ◽

Vapor Deposition Technique ◽

P Type ◽

Thermal Stability Of

AbstractThe thermal stability of Si/Si0.85Ge0.15/Si p-type modulation doped double heterostructures grown by the Ultra High Vacuum/ Chemical Vapor Deposition technique has been examined by Hall measurement, transmission electron microscopy, secondary ion mass spectroscopy, and Raman spectroscopy. As deposited heterostructures showed two-dimensional hole gas formation at the abrupt Si/SiGe and SiGe/Si interfaces. Annealing at 800 °C. for 1 hr. caused the diffusion of boron acceptors to the heterointerfaces, degrading the hole mobilities observed in the two dimensional hole gas. Rapid redistribution of boron, causing a loss of the 2 dimensional carrier behavior, was observed after a 900 °C, 0.5 hr. anneal. Neither Ge interdiffusion nor the generation of misfit dislocations were observed in the annealed heterostructures, evincing the defect-free crystal quality of these as-grown strained heteroepitaxial layers. The superior stability of these heterostructures have strong positive implications for Si:Ge heterojunction devices.

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Thermal stability of ZnO/ZnCdO/ZnO double heterostructures grown by pulsed laser deposition

Journal of Crystal Growth ◽

10.1016/j.jcrysgro.2011.06.030 ◽

2011 ◽

Vol 328 (1) ◽

pp. 13-17 ◽

Cited By ~ 4

Author(s):

M. Lange ◽

C.P. Dietrich ◽

G. Benndorf ◽

M. Lorenz ◽

J. Zúñiga-Pérez ◽

...

Keyword(s):

Thermal Stability ◽

Pulsed Laser Deposition ◽

Pulsed Laser ◽

Laser Deposition ◽

Double Heterostructures ◽

Thermal Stability Of

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Influence of Bath Additives on the Thermal Stability of the Nanostructure and Hardness of Ni Films Processed by Electrodeposition

Coatings ◽

10.3390/coatings9100644 ◽

2019 ◽

Vol 9 (10) ◽

pp. 644 ◽

Cited By ~ 5

Author(s):

Tamás Kolonits ◽

Zsolt Czigány ◽

László Péter ◽

Imre Bakonyi ◽

Jeno Gubicza

Keyword(s):

Thermal Stability ◽

Driving Force ◽

Defect Density ◽

Trisodium Citrate ◽

Free Sample ◽

Three Samples ◽

Different Temperatures ◽

Thermodynamic Driving Force ◽

Thermal Stability Of ◽

Bath Additives

The effect of bath additives on the thermal stability of the microstructure and hardness of nanocrystalline Ni foils processed by electrodeposition was studied. Three samples with a thickness of 20 μ m were prepared: one without any additive and two others with saccharin or trisodium citrate additives. Then, the specimens were heat-treated at different temperatures up to 1000 K. It was found that for the additive-free sample the recovery of the microstructure and the reduction of the hardness started only at temperatures higher than 500 K. At the same time, a decrease of the defect density and hardness was observed even at 400 K for the additive-containing films. This was explained by the higher defect density, which increased the thermodynamic driving force for recovery during annealing. At the highest applied temperature (1000 K), this larger thermodynamic driving force resulted in a recrystallization in the sulfur-containing sample, leading to a very low hardness of about 1000 MPa as compared to the additive-free sample (1300 MPa). On the other hand, the sample deposited with trisodium citrate additive showed a better thermal stability at 1000 K than the additive-free sample: the hardness remained as high as 2000 MPa even at 1000 K.

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The Influence of Random Defect Density on the Thermal Stability of Kaolinites

Journal of the American Ceramic Society ◽

10.1111/j.1551-2916.2005.00194.x ◽

2005 ◽

Vol 88 (4) ◽

pp. 1017-1019 ◽

Cited By ~ 8

Author(s):

Hongping He ◽

Peng Yuan ◽

Jiugao Guo ◽

Jianxi Zhu ◽

Cheng Hu

Keyword(s):

Thermal Stability ◽

Defect Density ◽

Thermal Stability Of ◽

Random Defect

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The Ordered Phase Formation in Ti-Al-Ga Alloys

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100069193 ◽

1970 ◽

Vol 28 ◽

pp. 440-441

Author(s):

Shiro Fujishiro ◽

Harold L. Gegel

Keyword(s):

Thermal Stability ◽

High Temperature ◽

Titanium Alloys ◽

Growth Kinetics ◽

Stoichiometric Composition ◽

Good Potential ◽

Alpha Titanium ◽

Cold Rolled ◽

Kinetics Of ◽

Thermal Stability Of

Ordered-alpha titanium alloys having a DO19 type structure have good potential for high temperature (600°C) applications, due to the thermal stability of the ordered phase and the inherent resistance to recrystallization of these alloys. Five different Ti-Al-Ga alloys consisting of equal atomic percents of aluminum and gallium solute additions up to the stoichiometric composition, Ti3(Al, Ga), were used to study the growth kinetics of the ordered phase and the nature of its interface.The alloys were homogenized in the beta region in a vacuum of about 5×10-7 torr, furnace cooled; reheated in air to 50°C below the alpha transus for hot working. The alloys were subsequently acid cleaned, annealed in vacuo, and cold rolled to about. 050 inch prior to additional homogenization

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Microstructure studies of tungsten silicide schottky contacts on Gaas

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100126445 ◽

1987 ◽

Vol 45 ◽

pp. 328-329

Author(s):

Yih-Cheng Shih ◽

E. L. Wilkie

Keyword(s):

Thermal Stability ◽

Field Effect Transistors ◽

Schottky Contact ◽

Schottky Contacts ◽

Excellent Thermal Stability ◽

Barrier Heights ◽

Gaas Substrates ◽

Film Adhesion ◽

Threshold Voltages ◽

Thermal Stability Of

Tungsten silicides (WSix) have been successfully used as the gate materials in self-aligned GaAs metal-semiconductor-field- effect transistors (MESFET). Thermal stability of the WSix/GaAs Schottky contact is of major concern since the n+ implanted source/drain regions must be annealed at high temperatures (∼ 800°C). WSi0.6 was considered the best composition to achieve good device performance due to its low stress and excellent thermal stability of the WSix/GaAs interface. The film adhesion and the uniformity in barrier heights and ideality factors of the WSi0.6 films have been improved by depositing a thin layer of pure W as the first layer on GaAs prior to WSi0.6 deposition. Recently WSi0.1 has been used successfully as the gate material in 1x10 μm GaAs FET's on the GaAs substrates which were sputter-cleaned prior to deposition. These GaAs FET's exhibited uniform threshold voltages across a 51 mm wafer with good film adhesion after annealing at 800°C for 10 min.

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