• Korean Journal of Heritage: History & Science
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• v.50 no.3
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• pp.4-29
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• 2017

The purpose of this study is to grasp the commencement date of Korean-type bronze dagger through the chronology of Chinese data. It focuses on the fact that the same section polishing technique appears both in Korean type bronze dagger and Dongzhou type bronze dagger. Dongzhou type bronze dagger in Anqiu Shandong, in which A1 type section polishing technique is observed, was said to have been collected remains in 1958, but the clear excavation cannot be identified. Therefore, this study presents Tomb No.1 Zuojiawa Jinan, Dongzhou type bronze dagger, and associated products. As associated products, bronze weapon and bronze ware were excavated, whose periods are estimated to be in the Spring and Autumn period, the transition period of Warring States, and the former part of the China's Warring States. Accordingly, the Korean bronze dagger, excavated in the remains of the Han Peninsula appears to have run parallel with the Dongzhou type bronze dagger of the A1 type section polishing technique, excavated in China for a fixed period. In addition, the chronology of Tomb No. 61MI grave in Wanrongmiaoqian, Shanxi is estimated to range from the former part to the middle part of the China's Warring States, which is identified to be connected to the A1 type section polishing technique. Examining the data of the relative date, we can find out that the Commencement Period of the Korean type bronze dagger Culture is seen to be the transition period and the former part of the China's Warring States, which is estimated to be the 5th and 4th centuries BC. This chronology is followed by Tomb No.6512 Zhengjiawazi Shenyang, recorded as the 6th century B.C. which reveals that Liaoning type bronze dagger culture and Korean-typed Bronze Dagger Culture are naturally connected. Furthermore, the A1 type section polishing technique was distributed in the southwestern area of the Korean peninsula and Shandong, China, while the A2 type section polishing technique was distributed in the southern area of the Korean peninsula, Shanxi-Province in China, and Northern Kyushu region in Japan. Seen from the weapon-shaped bronze ware of the section polishing technique, Shanxi area(Central Plains area), China. the southwestern area of the Korean peninsula (northwest area), and Northern Kyushu region in Japan are set up as one traffic road(spreading route). This demonstrates that the section polishing technique emerged around the Han Peninsular, spreading the technique regionally.

• Applied Microscopy
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• v.47 no.2
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• pp.77-83
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• 2017

Drastic development of ubiquitous devices requires more advanced batteries with high specific capacitance and high rate capability. Large-area microstructure characterization across the stacks of cathode, electrolyte and anode might reveal the origin of the instability or degradation of batteries upon cycling charge. In this study, sample preparation methods to observe the cross-section view of the electrodes for battery in SEM and several imaging tips are reviewed. For an accurate evaluation of the microstructure, ion milling which flats the surface uniformly is recommended. Pros and cons of cross-section polishing (CP) with Ar ion and focused ion beam (FIB) with Ga ion were compared. Additionally, a modified but new cross-section milling technique utilizing precision ion polishing system (PIPS) which can be an alternative method of CP is developed. This simple approach will make the researchers have more chances to prepare decent large-area cross-section electrode for batteries.

• Progress in Superconductivity and Cryogenics
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• v.8 no.1
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• pp.9-14
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• 2006

Sample preparation plays a critical role in microstructure analysis using TEM. Although TEM specimen has been usually prepared by jet-polishing or Ar-ion beam milling technique. these methods could not be applied to YBCO CC which is composed of IBAD or RABiTS substrates, several buffet layers, and YBCO superconducting layer because of big difference in mechanical strengths between the metallic phase and oxide phases. To obtain useful cross-sectional information such as interface between the phases or second phases in YBCO CC, it is prerequisite to secure the large area of thin section in the cross-sectional direction. The superconducting layer or the buffer layers are relatively weak and fragile compared to the metallic substrate such as Ni-5wt%W RABiTS of Hastelloy-based IBAD, and preferential removal of weak ceramic phases during polishing steps makes specimen preparation almost impossible. Tripod polisher and small jig were home-made and employed to sample preparation. The polishing angle was maintained <$1^{\circ}$ throughout the polishing steps using 2 micrometers attached to the tripod plate. TEM specimens with large and thin area could be secured and used for RABiTS/IBAD substrate analyses. In some cases, additional Ar-beam ion milling with low beam current and impinging angle was used for less than 30 sec. to remove debris or polishing media attacked to the specimens.

• The Journal of the Korean dental association
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• v.49 no.1
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• pp.22-32
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• 2011

This paper reviewed the following subheadings and a few selected references in each section were discussed: ${\cdot}$ Sealant placed over caries; is it possible? Initial caries which is not sticky during proving is possible to be placed with sealants. ${\cdot}$ Prophylaxis of fissure; which method is most effective? Mechanical preparation with fissurotomy or resin polishing bur is one of the most effective method to clean the pit and fissure. ${\cdot}$ Glassionomer cement as a sealant; GIC, wheather it released fluoride or not, cannot be as cost-effective as resin-based sealants. ${\cdot}$ Sealant products; Color(white vs opaque), fluoride(containing vs not), filler component(filled vs non-filled) do not influenced the quality and retention of sealants. ${\cdot}$ Use of intermediate bonding agent to improve retention; Intermediate bonding may increase the retention rate of sealants ${\cdot}$ Penetration method of sealants; Several methods including waiting before light curing are recommended.

• Applied Microscopy
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• v.39 no.3
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• pp.277-281
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• 2009

Practical difficulties for preparing a good crosssectional specimen of GaN-based materials for transmission electron microscopy have arisen due to large difference of mechanical properties between hard ceramic substrate and soft GaN-layered materials. Uneven polishing, sudden cracking, delamination, and selective sputtering during the conventional wedge polishing technique are often encountered as experimental hindrances. The preparation technique based on Strecker's method can be applied to overcome these difficulties, which eventually leads to mechanically stable TEM samples independent of the mechanical properties of materials. The basic idea is to use hard ceramic dummy filler for embedding the sample of interest into the dummy frame. In this study, we applied this technique into preparing cross-sectional TEM specimen of the GaN-based materials with mechanical instability and demonstrated usefulness of this hard dummy filler method in which the possible modifications of the sample of interest during the preparation must be avoidable. In addition, practical precautions during the preparation were discussed.

• Journal of the Korean Society for Precision Engineering
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• v.18 no.12
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• pp.192-199
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• 2001

Chemical mechanical planarization (CMP) has emerged as the planarization technique of choice in both front-end and back-end integrated circuit manufacturing. Conventional CMP process utilize a polyurethane polishing pad and liquid chemical slurry containing abrasive particles. There hale been serious problems in CMP in terms of repeatability and deflects in patterned wafers. Especial1y, dishing and erosion defects increase the resistance because they decrease the interconnection section area, and ultimately reduce the lifetime of the semiconductor. Methods to reduce dishing & erosion have recently been interface hardness of the pad, optimization of the pattern structure as dummy patterns. Dishing & erosion are initially generated an uneven pressure distribution in the materials. These defects are accelerated by free abrasives and chemical etching. Therefore, it is known that dishing & erosion can be reduced by minimizing the abrasive concentration. Minimizing the abrasive concentration by using CeO$_2$is the best solution for reducing dishing & erosion and for removal rate. This paper introduce dishing & erosion generating mechanism and a method fur developing a semi-rigid abrasive pad to minimize dishing & erosion during CMP.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.44 no.4
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• pp.16-24
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• 2012

To characterize the coating structure, diverse methods such as mercury intrusion, nitrogen adsorption and oil absorption methods have been developed and widely employed. These indirect techniques, however, have some limitation to explain the actual coating structure. Recently microscopic observation methods have been tried for analyzing structural characteristics of coating layers. Preparation of the undamaged cross section of a coating layer is essential for obtaining high quality image for analysis. In this study, distortion-free cross-section of the coating layer was prepared using a grinding and polishing technique. The coated paper was embedded in epoxy resin and cured. After curing the resin block it was ground with abrasive papers and then polished with diamond particle suspension and nylon cloth. Polished coating layer was sufficient enough to obtain undamaged cross sectional images with scanning electron microscope under backscattered electron image mode. In addition, the SEM images allowed distinction of the coating layer components. Also S/B latex film formed between pigment particles was visualized by osmium tetroxide staining. Pore size distribution and pore orientation were evaluated by image analysis from SEM cross-sectional images.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2001.04a
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• pp.1117-1120
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• 2001

Chemical mechanical planarization(CMP) has emerged as the planarization technique of choice in both front-end and back-end integrated circuit manufacturing. Conventional CMP process utilize a polyurethane polishing pad and liquid chemical slurry containing abrasive particles. There have been serious problems in CMP in terms of repeatability and defects in patterned wafers. Since IBM's official announcement on Copper Dual Damascene(Cu2D) technology, the semiconductor world has been engaged in a Cu2D race. Today, even after~3years of extensive R&D work, the End-of-Line(EOL) yields are still too low to allow the transition of technology to manufacturing. One of the reasons behind this is the myriad of defects associated with Cu technology. Especially, dishing and erosion defects increase the resistance because they decrease the interconnection section area, and ultimately reduce the lifetime of the semiconductor. Methods to reduce dishing & erosion have recently been interface hardness of the pad, optimization of the pattern structure as dummy patterns. Dishing & erosion are initially generated an uneven pressure distribution in the materials. These defects are accelerated by free abrasive and chemical etching. Therefore, it is known that dishing & erosion can be reduced by minimizing the abrasive concentration. Minimizing the abrasive concentration by using Ce$O_2$ is the best solution for reducing dishing & erosion and for removal rate. This paper introduce dishing & erosion generating mechanism and a method for developing a semi-rigid abrasive pad to minimize dishing & erosion during CMP.

• Korean Journal of Heritage: History & Science
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• v.53 no.4
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• pp.170-187
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• 2020

Dolmens bearing the burial layout and stone coffin tombs of the late Bronze Age were excavated from Samdeok-ri, Goseong, Gyeonsangnsamdo, and grave items such as red-burnished pottery, arrowheads, and stone swords were also discovered. In the case of the red-burnished pottery that was found, it retains a pigment layer with a thickness of about 50 to 160㎛, but with most of the other items, exfoliation and peeling-off of pigment layers can be observed on the surface. The raw materials of the red-burnished pottery contained moderately sorted minerals such as quartz, feldspar, and hornblende, and partly opaque iron oxide minerals were also identified. In particular, the raw materials of the red-burnished pottery from stone coffin tomb #6 were different from those of the other pottery, containing large amounts of hornblende and feldspar. The pottery's red pigment was identified as hematite and showed similar mineral content of raw materials such as fine grained quartz, feldspar, and hornblende. The firing temperature is estimated to have been approximately 900℃, based on their mineral phase. The possibility exists that the raw materials had been collected from the Samdeok-ri area, because diorite and granite diorite with dominant feldspar and hornblende have been identified within 3km of that area. During the pottery manufacturing process, it is estimated that the pigment was painted on the entire surface of the red-burnished pottery after it had been molded and then finished using the abrasion technique. In other words, the red-burnished pottery was made by the process of vessel forming - semi drying - coloring - polishing. The surface and cross-section of the pottery appears differently depending on the concentration of the pigment and the coloring method used after vessels were formed. Most of the excavated pottery features a distinct boundary between pigment and body fabric. However, in the case of pottery in which fine-grained pigments penetrate the body fabric so that layers cannot be distinguished, there is the possibility that the fine-grained pigment layer was applied at a low concentration or immediately after vessel forming. Many cracks can be seen on the surface pigments in thickly painted pottery items, and in many cases, only a small portion of the pigment layers remain due to surface exfoliation and abrasion in the burial environment. It is reported that pottery items may be more easily damaged by abrasion if coated with pigment and polished, so it is believed that the red-burnished pottery of the Samdeok-ri site suffered from weathering in the burial environment. This damage was more extensive in the potsherds that were scattered outside the tomb.