• Journal of the Korean Society for Heat Treatment
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• v.18 no.4
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• pp.223-228
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• 2005

Tube hydroforming provides a number of advantages over conventional stamping process, including fewer secondary operation, weight reduction, assembly simplification, adaptability to forming of complex structural components and improved structural strength and stiffness. It can produce wide range of products such as subframe, engine cradle, and exhaust manifold. In this study, the effect of the heat treatment conditions such as post seam annealing (PSA) and bright annealing (BA) on the ovality and hydro-formability of steel tubes has been investigated. Hydroformabilities have been estimated by the bulging heights obtained at various processing parameters such as internal pressure, axial feeding and heat treatment conditions. The ovality and forming height are strongly influenced by material properties after heat treatments.

• Transactions on Electrical and Electronic Materials
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• v.15 no.1
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• pp.16-19
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• 2014

Charge trapping nonvolatile memory capacitors with $ZrO_2$ as charge trapping layer were fabricated, and the effects of post annealing atmosphere ($NH_3$ and $N_2$) on their memory storage characteristics were investigated. It was found that the memory windows were improved, after annealing treatment. The memory capacitor after $NH_3$ annealing treatment exhibited the best electrical characteristics, with a 6.8 V memory window, a lower charge loss ~22.3% up to ten years, even at $150^{\circ}C$, and excellent endurance (1.5% memory window degradation). The results are attributed to deep level bulk charge traps, induced by using $NH_3$ annealing.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2009.06a
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• pp.460-461
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• 2009

We studied the effects of post-annealing treatment on poly(3-hexylthiophene)(P3HT, donor):[6,6]-phenyl $C_{61}$ butyric acid methyl ester(PCBM, acceptor) blend film as an active layer in the organic solar cells(OSCs). For the formation of the active layer, 3 wt.% P3HT:PCBM solution in chlorobenzene were deposited by spin-coating method. In order to optimize the performance of OSCs, the P3HT crystallization and the redistribution of PCBM cluster at P3HT:PCBM composition as a function of post-annealing condition from room temperature to $200^{\circ}C$ were measured by the Hall effect and the UV-vis Spectrophotometer. We thought that the improved efficiency in the OSCs with post-annealing treatment at $150^{\circ}C$ can be explained by the efficient separation or collection of the photogenerated excitons at donor-acceptor interface by P3HT crystallization.

• Proceedings of the KIEE Conference
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• 2015.07a
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• pp.1151-1152
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• 2015

Silicon zinc oxide (SZO) thin films were deposited via co-sputtering. Two kinds of post-treatment, furnace annealing and hot pressing, were carried out on the deposited SZO films. The effects of the post-treatment on the chemical bond and surface roughness of the deposited SZO films were analyzed as functions of the post-treatment conditions that were used. It was observed from the X-ray photoelectron spectroscopy (XPS) results that the amount of Si-O bonds in the SZO film drastically increased after the low-temperature furnace annealing. The experiment results showed that the hot pressing method would be favorable as it could improve the electrical characteristics of the SZO-TFTs.

• Journal of the Korean Ceramic Society
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• v.37 no.8
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• pp.731-738
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• 2000

KLN(K3Li2Nb5O15) has attracted a great deal of attention for their potential usefulness in piezoelectric, electro-optic, nonlinear optic, and pyroelectirc devices. Especially, the KLN single crystal has been studied in the field of optics and electronics. However it is hard to produce good quality single crystals due to the crack propagation during crystal growing. One of the solutions of this problem is prepartion of thin film. But the intensive study has not been conducted so far. In this study, after the KLN thin film were prepared by R.F. magnetron Sputtering method on SiO2/Si substrate, the post-annealing methods of RTA(rapid thermal annealin) and IPA(insitu post annealing) were employed. The deposition condition of KLN thin film was RF power(100 W), Working pressure(100 mtorr). The commonness of both RAT and IPA was that the higher were deposition and post annealing temperature, the higher was the intensity of XRD but the less surface roughness. The difference of post-annealing methods affected XRD phase and surface condition very much. And in IPA process, the influence of O2 had much effect on the formation of KLN phase.

• Transactions on Electrical and Electronic Materials
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• v.2 no.1
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• pp.22-26
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• 2001

ITO (Indium-tin-oxide) thin films were deposited on glass substrates by a dc magnetron sputtering system using ITO powder target. The methods of heat treatment are important factor to obtain high quality ITO films with low electrical resistivity and good optical transmittance. Therefore, both methods of the substrate temperature and post-deposition annealing temperature have been compared on the film structural, electrical and optical properties. A preferred orientations shifts from (411) to (222) peak at annealing temperature of 200$\^{C}$. Minimum resistivity of ITO film is approximately 8.7$\times$10$\^$-4/ Ωcm at substrate temperature of 450$\^{C}$. Optical transmittances at post annealing temperature above 200$\^{C}$ are 90%. As a result, the minimum value of annealing temperature that is required for the recrystallization of as-deposited ITo thin films is 200$\^{C}$.

• Journal of the Korean Society for Heat Treatment
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• v.37 no.1
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• pp.9-15
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• 2024

Nd-Fe-B permanent magnets have been utilized on various industrial fields such as electric vehicles, generator, robots with actuator, etc, due to their outstanding magnetic properties even 10 times better than conventional magnets. Recently, there are many researches that report magnetic properties improved by controlling microstructure through adjusting alloying elements or conducting various processing. Especially, post-sintering annealing (PSA) can significantly improve the coercivity by modifying the distribution and morphology of Nd-rich phase which formed at grain boundaries. In this study, Nd-Fe-B sintered magnets were subjected to primary heat treatment followed by secondary heat treatment at 460℃, 500℃, and 540℃ to investigate the changes in microstructure and magnetic properties with the secondary heat treatment temperature. EBSD analysis was conducted to compare anisotropic characteristics. Through the SEM and TEM observation for analyzing the morphology and distribution of Nd-rich phase, we investigated the relationship between microstructure and magnetic properties of sintered Nd-Fe-B magnets.

• Transactions of Materials Processing
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• v.31 no.4
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• pp.179-185
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• 2022

The influence of post-roll bonding heat treatment conditions such as temperature and time on the variation in the diffusion layer, generated at the bonding interface and the subsequent mechanical properties of the roll-bonded Ti grade 1/Al1050/Ti grade 1 sheets, was systematically investigated. The intermetallic compound (IMC) phase generated by post heat treatment conditions adopted in this study was obviously indexed as monolithic TiAl₃. Whereas the thickness of IMC layer generated by annealing at 500 ℃ was approximately 100 nm scale, it drastically increased above 1.5 ㎛ when annealed at 600 ℃. Uniaxial tensile and peel tests were then performed to compare mechanical properties. As a result, the bonding strength drastically increased above 7.9 N/mm by annealing at 600 ℃, which implies that proper annealing condition was a prerequisite, to improving interface bonding strength as well as global elongation properties for Ti/Al/Ti 3-ply sheet.

• New & Renewable Energy
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• v.17 no.4
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• pp.36-45
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• 2021

To remove the Cu secondary phase remaining on the surface of a CIGSSe absorber layer manufactured by the two-step process, KCN etching was applied before depositing the CdS buffer layer. In addition, it was possible to increase the conversion efficiency by air annealing after forming the CdS buffer layer. In this study, various pre-treatment/post-treatment conditions wereapplied to the S-containing CIGSSe absorber layerbefore and after formation of the CdS buffer layer to experimentally confirm whether similareffects as those of Se-terminated CIGSe were exhibited. Contrary to expectations, it was noted that CdS air annealing had negative effects.

• Transactions on Electrical and Electronic Materials
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• v.16 no.2
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• pp.99-102
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• 2015

Thin film transistors (TFTs) with amorphous 2 wt% silicon-doped zinc tin oxide (a-2SZTO) channel layer were fabricated using an RF magnetron sputtering system, and the effect of post-annealing treatment time on the structural and electrical properties of a-2SZTO systems was investigated. It is well known that Si can effectively reduce the generation of oxygen vacancies. However, it is interesting to note that prolonged annealing could have a bad effect on the roughness of a-2SZTO systems, since the roughness of a-2SZTO thin films increases in proportion to the thermal annealing treatment time. Thermal annealing can control the electrical characteristics of amorphous oxide semiconductor (AOS) TFTs. It was observed herein that prolonged annealing treatment can cause bumpy roughness, which led to increase of the contact resistance between the electrode and channel. Thus, it was confirmed that deterioration of the electrical characteristics could occur due to prolonged annealing. The longer annealing time also decreased the field effect mobility. The a-2SZTO TFTs annealed at 500℃ for 2 hours displayed the mobility of 2.17 cm²/Vs. As the electrical characteristics of a-2SZTO annealed at a fixed temperature for long periods were deteriorated, careful optimization of the annealing conditions for a-2SZTO, in terms of time, should be carried out to achieve better performance.