scholarly journals Effect of the Sputtering Deposition Conditions on the Crystallinity of High-Temperature Annealed AlN Films

Coatings ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 956
Author(s):  
Kenjiro Uesugi ◽  
Kanako Shojiki ◽  
Shiyu Xiao ◽  
Shigeyuki Kuboya ◽  
Hideto Miyake
Keyword(s):  
High Temperature ◽  
Chamber Pressure ◽  
Threading Dislocation ◽  
High Temperature Annealing ◽  
Oriented Growth ◽  
Sputtering Deposition ◽  
Face To Face ◽  
Aln Film ◽  
Before And After ◽  
Sputter Deposited

Face-to-face annealed sputter-deposited aluminum nitride (AlN) templates (FFA Sp-AlN) are a promising material for application in deep-ultraviolet light-emitting diodes (DUV-LEDs), whose performance is directly related to the crystallinity of the AlN film. However, the influence of the sputtering conditions and annealing on the crystallinity of AlN films have not yet been comprehensively studied. Accordingly, in this study, we fabricate AlN films on sapphire substrates through sputtering deposition followed by face-to-face high-temperature annealing, and investigate the influence of the sputtering conditions, such as the sputtering gas species and chamber pressure, on the crystallinity of the AlN films before and after annealing. The results revealed that reducing the amount of Ar in the sputtering gas significantly enhances the c-axis oriented growth during the initial stages of sputtering deposition and mitigates the tilt disorder of the layer deposited on the initial layer, resulting in low threading dislocation densities (TDDs) in the annealed AlN films. Decreasing the chamber pressure also effectively improves the crystallinity of the annealed AlN films. Thus, although high-temperature annealing can reduce the TDDs in AlN films, the properties of the as-sputtered AlN films have a significant effect on the crystallinity of FFA Sp-AlN films.

High Temperature Annealing SP-AlN Ameliorates the Crystal Quality ofAl0.5Ga0.5N Regrowth

2020 ◽  
Vol 1014 ◽  
pp. 14-21
Author(s):  
Wen Kai Yue ◽  
Zhi Min Li ◽  
Xiao Wei Zhou ◽  
Jin Xing Wu ◽  
Pei Xian Li
Keyword(s):  
Raman Spectroscopy ◽  
High Temperature ◽  
Annealing Process ◽  
High Temperature Annealing ◽  
High Quality ◽  
Rocking Curve ◽  
Stress Mode ◽  
Aln Film ◽  
Before And After ◽  
Screw Dislocation Density

In this study, the effect of a high-temperature annealing process on AlN is investigated. The high-temperature annealing process reduces the screw dislocation density of the AlN film to 2.1x107 cm-2. The AlN surface is highly flat. Through HRXRD and Raman spectroscopy, the stress mode changes in the sputtered AlN film before and after high-temperature annealing were studied in depth. Based on the HTA-AlN template, a high-quality, high-Al composition AlGaN epitaxial wafer, with a (0002) plane rocking curve FWHM of 246 arcsec , was prepared at 1080°C The growth mode of AlGaN grown directly on the AlN template at low temperature is summarized.

Suppression of SiC surface roughening during high-temperature annealing by atmospheric control using purified Ar gas

2010 ◽  
Vol 25 (4) ◽  
pp. 708-710 ◽  
Author(s):  
Atsushi Ogura ◽  
Daisuke Kosemura ◽  
Shingo Kinoshita
Keyword(s):  
Surface Roughness ◽  
High Temperature ◽  
Surface Roughening ◽  
Annealing Atmosphere ◽  
High Temperature Annealing ◽  
Force Microscopy ◽  
Atomic Force ◽  
Before And After ◽  
Furnace Tube ◽  
Ar Gas

4H-silicon carbide (SiC) wafers were annealed at 1300 and 1600 °C for 30 min and 60 min in a conventional and purified Ar atmosphere. The surface roughness before and after annealing was evaluated by atomic force microscopy. The surface roughness before annealing was approximately 2.37 nm in root mean square. The roughness, after annealing for 30 min at 1300 and 1600 °C in a conventional Ar furnace, was increased to 4.53 and 14.9 nm, respectively. The roughness, after annealing for 60 min, was 5.01 and 19.1 nm, respectively. In this study, the G3 grade Ar gas (99.999%) was supplied in the conventional furnace tube. When the Ar gas was purified to an impurity concentration of less than 1 ppb, and it was supplied in the leak-tight furnace tube, the roughness after 30-min annealing improved 4.27 and 6.93 nm at 1300 and 1600 °C, respectively. The roughness after 60-min annealing was also reduced to 3.54 and 9.28 nm, respectively. We assume that a significant reduction of H2O concentration in the annealing atmosphere might play an important role in suppressing surface roughening of SiC during high-temperature annealing.

Observation of Shrinking and Reformation of Shockley Stacking Faults by PL Mapping

2006 ◽  
Vol 527-529 ◽  
pp. 375-378 ◽  
Author(s):  
Toshiyuki Miyanagi ◽  
Hidekazu Tsuchida ◽  
Isaho Kamata ◽  
Tomonori Nakamura ◽  
R. Ishii ◽  
...  
Keyword(s):  
High Temperature ◽  
Laser Irradiation ◽  
High Power ◽  
Stacking Faults ◽  
High Temperature Annealing ◽  
High Power Laser ◽  
Power Laser ◽  
Before And After ◽  
Basal Plane Dislocation ◽  
Pl Mapping

We provide evidence of shrinking of Shockley-type stacking faults (SSFs) in the SiC epitaxial layer by high temperature annealing. Photoluminescence (PL) mapping in combination with high-power laser irradiation makes it possible to investigate the formation of SSFs, which lie between a pair of partial dislocations formed by dissociation of a basal plane dislocation (BPD), without fabrication of pin diodes. Using this technique, we investigated the annealing effect on SSFs. Comparing before and after annealing at 600°C for 10 min, it became obvious that high-temperature annealing results in shrinking of the faulted area of the SSFs. The SSFs form into the same features as those before annealing when high-power laser irradiation is performed again on the same area. This result shows that the faulted area of SSFs shrinks by 600°C annealing but the nuclei of SSFs (BPDs) do not disappear.

Crystallization kinetics of sputter-deposited LaNiO3 thin films on Si substrate

1998 ◽  
Vol 13 (8) ◽  
pp. 2291-2296 ◽  
Author(s):  
Hsin-Yi Lee ◽  
Tai-Bor Wu
Keyword(s):  
Thin Films ◽  
High Temperature ◽  
Crystallization Kinetics ◽  
Crystallization Rate ◽  
Diffraction Method ◽  
Sputtering Deposition ◽  
Diffusion Controlled ◽  
Activation Energy Of Crystallization ◽  
Sputter Deposited ◽  
Kinetics Of

The kinetics of in situ crystallization of LaNiO3 thin films in sputtering deposition at temperatures ranging from 250 to 450 °C and isothermal crystallization of room-temperature (RT) sputtered LaNiO3 thin films in annealing at 350–500 °C were investigated by the x-ray diffraction method. The crystallization in both cases basically followed the Johnson–Mehl–Avrami (JMA) relation. However, different crystallization kinetics were observed. The transformation index and activation energy of crystallization in high temperature sputtering were about 1.5 and 33 kJ/mole, respectively, while in the annealing of RT-sputtered films, 1.0 and 63 kJ/mole were found. From the determined transformation index, it is suggested that the crystallization rate in high temperature sputtering was determined by a diffusion-controlled process of lateral growth with a decreasing nucleation rate of crystallites in the adsorption layer. However, the annealed films crystallized by an interface-controlled and one-dimensional growth of existing nuclei.

Influence of High Temperature Annealing in Nitrogen on Upconversion Luminescence of β-NaYF4: Yb3+, Er3+ Hexagonal Sub-Microplates

2012 ◽  
Vol 496 ◽  
pp. 79-83
Author(s):  
Jun Wei Zhao ◽  
Tie Kun Jia ◽  
Xiang Gui Kong
Keyword(s):  
High Temperature ◽  
Sodium Citrate ◽  
Hexagonal Phase ◽  
Upconversion Luminescence ◽  
Annealing Treatment ◽  
Annealing Process ◽  
High Temperature Annealing ◽  
Nonradiative Relaxation ◽  
Before And After ◽  
Hydrothermal Methods

The pure β-NaYF4: Yb3+, Er3+ hexagonal sub-microplates were successfully prepared by the combination of coprecipitation and hydrothermal methods using sodium citrate as chelator. The size of them is about 600 nm × 400 nm (side length × thickness). The obtained sample was divided into two parts and one of them was annealed in nitrogen at 300 °C for 2 hours. The crystal structure of the β-NaYF4: Yb3+, Er3+ hexagonal sub-microplates before and after annealing treatment is hexagonal phase. Under the excitation of 980 nm diode laser, the upconversion luminescence intensity the sample after annealing is much stronger than that of the sample without annealing treatment. High temperature annealing process improved the crystallization of the sample, resulting in the decrease of the nonradiative relaxation and the enhancement of the upconversion luminescence.

scholarly journals Исследование состава и фазового состояния тонких пленок цирконата-титаната свинца, полученных высокочастотным магнетронным осаждением, при изменении давления рабочего газа

2019 ◽  
Vol 45 (6) ◽  
pp. 3
Author(s):  
Д.М. Долгинцев ◽  
В.П. Пронин ◽  
Е.Ю. Каптелов ◽  
С.В. Сенкевич ◽  
И.П. Пронин
Keyword(s):  
High Temperature ◽  
Lead Zirconate Titanate ◽  
Pyrochlore Structure ◽  
Rf Magnetron Sputtering ◽  
Lead Zirconate ◽  
Lead Content ◽  
High Temperature Annealing ◽  
Two Phase ◽  
Sputtering Deposition ◽  
Pzt Films

AbstractVariation of the working gas pressure (from 8 to 2 Pa) during RF magnetron sputtering deposition of thin perovskite lead zirconate titanate (PZT) films revealed strong changes in their lead content, which decreased below the stoichiometric level and led to the formation of a two-phase (perovskite–pyrochlore) structure upon subsequent high-temperature annealing. Measurements of the composition of perovskite islands in the two-phase films showed that the lead content in these islands was equal to or greater than stoichiometric. These results lead to the conclusion that the obtained PZT films are free of lead vacancies.

Conversion of Basal Plane Dislocations to Threading Edge Dislocations by High Temperature Annealing of 4H-SiC Epilayers

2012 ◽  
Vol 1433 ◽  
Author(s):  
Xuan Zhang ◽  
Hidekazu Tsuchida
Keyword(s):  
High Temperature ◽  
Basal Plane ◽  
Image Force ◽  
Line Tension ◽  
Grazing Incidence ◽  
High Temperature Annealing ◽  
X Ray ◽  
Before And After ◽  
Edge Dislocations ◽  
Epilayer Surface

ABSTRACTConversion of basal plane dislocations (BPDs) to threading edge dislocations (TEDs) has been observed in 4H-SiC epilayers by simple high temperature annealing. Grazing incidence reflection synchrotron X-ray topography was used to image the dislocations in the epilayers. By comparing the X-ray topographs before and after annealing, some of the BPDs were confirmed to convert to TEDs from the epilayer surface. The dislocation behaviors during annealing are explained and the mechanism of BPD conversion is discussed. It is argued that the conversion process is realized by constricted BPD segments cross-slipping to the prismatic plane driven by the image force and TED glide on its slip plane driven by the line tension. Certain kinetic processes may assist the formation of constrictions on the BPDs.

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