• Journal of the Korean Magnetics Society
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• v.26 no.1
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• pp.7-12
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• 2016

Effects of annealing of the gas-atomized Fe-9%Si-2%Cr powder which is suitable for high frequency application in mobile devices because of its high electrical resistivity were studied with an emphasis on the order-disorder phase transition. The formation of B2 ordered phase could not be suppressed during atomization process. When the powder was annealed at a temperature higher than $550^{\circ}C$ the peak diffracted from $DO_3$ phase could be detected. With increasing annealing temperature lattice parameter and coercivity decreased. An interesting phenomenon was an abrupt increment of coercivity in the powder annealed at $450^{\circ}C$. Highest permeability could be shown in the powder annealed at a relative low temperature of $150^{\circ}C$ and then the permeability decreased with annealing temperature. The above-mentioned results could be successfully explained by both the formation of $DO_3$ ordered phases and the change of electrical resistivity of the Fe-Si-Cr powder which was also originated from the phase transition.

• The Korean Journal of Ceramics
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• v.3 no.4
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• pp.274-278
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• 1997

(Ba, Sr) TiO$_3$(BST) thin films were prepared on RuO$_2$/Si substrates by rf magnetron sputtering and annealing was followed at temperatures ranging from 550 to 80$0^{\circ}C$ in $N_2$or $O_2$atmosphere. The effects of annealing conditions on the properties of BST film deposited on RuO$_2$bottom electrodes were investigated. It was found that the crystallinity. surface roughness, and grain size of BST films vary with the annealing temperature but they are not dependent upon the annealing atmosphere. The flat region in the current-voltage (I-V) curves of BST capacitors shortened with increasing annealing temperature under both atmospheres. This is believed to be due to the lowering of potential barrier caused by unstable interface and the increase of charge The shortening of the flat region by $O_2$annealing was more severe than that by $N_2$-annealing. As a result, there was no flat region when the films were annealed at 700 and 80$0^{\circ}C$ in $O_2$atmosphere. The dielectric properties of BST films were improved by annealing in either atmosphere. however, a degradation with frequency was observed when the films were annealed at relatively high temperature under $O_2$atmosphere.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.17 no.4
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• pp.130-136
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• 2018

In this paper, the effects of different 3D printing parameters including laminated angle and annealing temperature, were observed for their effects on tensile testing. In 3D printing, a filament is heated quickly, extruded, and then cooled rapidly. Because plastic is a poor heat conductor, it heats and cools unevenly causing the rapid heating and cooling to create internal stress within the printed part. Therefore, internal stress can be removed using annealing and to increase tensile strength and strain. During air cooling at annealing temperature $140^{\circ}C$, the strain of laminated angle $45^{\circ}$ specimens tended to increase by 46% while the tensile stress tended to increase by 7.4%. During oven cooling at annealing temperature $140^{\circ}C$, the strain of laminated angle $45^{\circ}$ specimens tended to increase by 34% while the tensile stress tended to increase by 22.2%. In this study, we found "3D printing with annealing" eliminates internal stress and increases the strength and stiffness of a printed piece. On the microstructural level, annealing reforms the crystalline structures to even out the areas of high and low stress, which created fewer weak areas. These results are very useful for making 3D printed products with a mechanical strength that is suitable for applications.

• Journal of the Korean Society for Heat Treatment
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• v.21 no.6
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• pp.293-299
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• 2008

In order to provide with fundamental data of the wrought Mg alloy for press forging, the effect of annealing temperature on the microstructure, texture development and tensile properties is studied in a commercial AZ31B Mg alloy sheet. Basal texture i.e. $(0001){\pm}5^{\circ}$[21$\bar{3}$0] is developed in a commercial AZ31B Mg sheet, and the texture is not changed considerably by annealing over $400^{\circ}C{\times}30min$, while (10$\bar{3}$0) component with high intensity can be observed due to abnormal grain growth. When the sheet is tensile-deformed with RD, $45^{\circ}$ and TD directions at room temperature, fracture strains are given by 25.8, 21.4 and 11.9% in the order of RD, $45^{\circ}$ and TD directions, respectively. With increasing annealing temperature up to $450^{\circ}C{\times}30min$, little change in mean grain size can be revealed by annealing below $300^{\circ}C{\times}30min$ but an abnormal grain growth, where some grains become significantly coarser than the rest, occurs by annealing above $400^{\circ}C{\times}30min$. The maximum tensile strain of around 25% is obtained by annealing below $300^{\circ}C{\times}30min$, but it is abruptly decreased to 16% by annealing above $400^{\circ}C{\times}30min$ owing to intergranular fracture of abnormal grown grains.

• Journal of the Korean Magnetics Society
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• v.2 no.2
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• pp.91-98
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• 1992

In a $Co_{67}Fe_{4.5}Nb_{2}Si_{10}B_{15}$ amorphous alloy ribbon the effect to two-step annealing on the soft magnetic properties has been studied. By two-step annealing method which the second annealing at low temperature of $310^{\circ}C$ for 2 hours is undertaken after the primary annealing at high temperature above $480^{\circ}C$ for 20 minutes at the vacuum state, the coercive force and the squareness are not changed nearly but the initial permeability at d.c. and the effective permeability at a.c. are remark-ably increased compared with the one-step annealing. The maxima of the initial permeability and the effective permeability at 1 kHz after the two-step annealing are 290,000 and 41,000, respectively, which are 30% higher than those of the one-step annealing. The change of magnetic properties with annealing temperature is discussed in terms of the residual stress, the domain size, the cluster and the crystalline phase.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.11b
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• pp.346-349
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• 2001

We studied the nematic liquid crystal (NLC) aligning capabilities using the new alignment material of diamond like carbon (DLC) thin film. A high pretilt angle of about $4^{\circ}$ was measured by ion beam(IB) exposure on the DLC thin film surface. A good LC alignment was observed by the IB alignment method on the DLC thin film surface at annealing temperature of $200^{\circ}C$, and the alignment defect of the NLC was observed above annealing temperature of $220^{\circ}C$. Consequently, the high NLC pretilt angle and the good thermal stability of LC alignment can be achieved by the IB alignment method on the DLC thin film surface.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.11a
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• pp.346-349
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• 2001

We studied the nematic liquid crystal (NLC) aligning capabilities using the new alignment material of diamond like carbon (DLC) thin film. A high pretilt angle of about 4$^{\circ}$ was measured by ion beam(IB) exposure on the DLC thin film surface. A good LC alignment was observed by the IB alignment method on the DLC thin film surface at annealing temperature of 200$^{\circ}C$, and the alignment defect of the NLC was observed above annealing temperature of 220$^{\circ}C$ . Consequently, the high NLC pretilt angle and the good thermal stability of LC alignment can be achieved by the IB alignment method on the DLC thin film surface.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.15 no.5
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• pp.419-422
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• 2002

We studied the nematic liquid crystal (NLC) aligning capabilities using the new alignment material of a diamond like carbon (DLC) thin film. A high pretilt angle of about $3.5^{\circ}$ by ion beam(IB) exposure on the DLC thin film surface was measured. A good LC alignment by the IB alignment method on the DLC thin film surface was observed at annealing temperature of $200^{\circ}C$, and the alignment defect of the NLC was observed above annealing temperature of $220^{\circ}C$. Consequently, the high NLC pretilt angle and the good thermal stability of LC alignment by the IB alignment method on the DLC thin film surface can be achieved.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.16 no.7
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• pp.584-592
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• 2003

6H-SiC MOSFETs and digital ICs have been fabricated and characterized. PMOS devices are fabricated on an n-type epilayer while the NMOS devices are fabricated on implanted p-wells. NMOS and PMOS devices use a thermally grown gate oxide. SiC MOSFETs are fabricated using different impurity activation methods such as high temperature and newly proposed laser annealing methods. Several digital circuits, such as resistive road NMOS inverters, CMOS inverters, resistive road NMOS NANDs and NORs are fabricated and characterized.

• Journal of the Korean Institute of Telematics and Electronics A
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• v.31A no.9
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• pp.78-88
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• 1994

The electrical properties of TiM/TiSi$_{2}$ bilayer formed by rapid thermal anneal in NH$_{3}$ ambient after the Ti film is deposited on silicon cubstrate are investigated. N$^{+}$ contact resistance slightly increases with increasing annealing temperature with P$^{+}$ contact resistance decreases. The contact resistance of N$^{+}$ contance was less than 24[.OMEGA.] but P$^{+}$ thatn that of N$^{+}$ contact but the leakage current indicates degradation of the contact at high annealing temperature for both N$^{+}$ and contacts. The leakage current of N$^{+}$ Junction was less than 0.06[fA/${\mu}m^{2}$] but P$^{+}$ contact was 0.11-0.15[fA/${\mu}m^{2}$]. The junction breakdown voltage for N$^{+}$ junction remains contant with increasing annealing temperature while P$^{+}$ junction slightly decreases. The Electrical properties of a two step annealing are better than that of one step annealing. The Tin/TiSi$_{2}$ bilayer formed by RTA in NH$_{3}$ ambient reveals good electrical properties to be applicable at ULSI contact.