• The Transactions of the Korean Institute of Electrical Engineers C
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• v.50 no.9
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• pp.438-443
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• 2001

In the shallow trench isolation(STI)-chemical mechanical polishing(CMP) process, the key issues are the optimized thickness control, within-wafer-non-uniformity, and the possible defects such as pad oxide damage and nitride residue. The defect like nitride residue and silicon (or pad oxide) damage after STI-CMP process were discussed to accomplish its optimum process condition. To understand its optimum process condition, overall STI related processes including reverse moat etch, trench etch, STI fill and STI-CMP were discussed. Consequently, we could conclude that law trench depth and high CMP thickness can cause nitride residue, and high trench depth and over-polishing can cause silicon damage.

• Proceedings of the KWS Conference
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• 2006.10a
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• pp.181-183
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• 2006

This paper studies the mechanical behaviors of Sn-3.5Ag solder joint against substrate(such as Au/Ni/Cu, Au/cu, Ni/Cu and Cu pad) after induction heating, a new soldering method. It was found that the solder bump formation depends on the time and current of the induction heating system. Also the heating value of the solder bump were found to vary with respect to the thermal conductivity of the pads on the substrate. In case of Au/Ni/Cu pad and Au/Cu pad, solder bump's shear strength were high for the heating time of $1.5{\sim}2sec$. For Ni/Cu pad, solder bump's shear strength were found to increase with time increment.

• Journal of the Earthquake Engineering Society of Korea
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• v.3 no.3
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• pp.1-8
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• 1999

The bridges for Korea High-Speed Railway(KHSR) under construction are supported with pot bearings on the middle pier and with pad bearings on the side piers, respectively. The dynamic analysis on these bridges due to trains with high speed, however, has been performed neglecting the effects of bearings. The objective of this study is investigation on the dynamic behavior of bridge supported by pad bearings. The effects of pad bearings with various flexibilities on the dynamic responses of bridges are studied. From the results of this study, the effects of elastomeric bearing on the dynamic responses of bridge(especially vertical accelerations) may cause undesirable behaviors.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 1999.04a
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• pp.226-233
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• 1999

When we numerically model the bridge under seismic condition, the full model combining the super-structure and the sub-structure is considered for the more accurate results than the separate model. In this case, the super-structure is connected with the sub-structure by the elastic pad shoe that is difficult to model, because it has the three translational elastic stiffness and the three rotational elastic stiffness. The two-node General Link element is derived in finite element equation representing such a pad shoe, and it is verified by comparing the one General Link element model with the corresponding three legacy spring element model. It is easy to model the pad shoe, if the General Link finite element is used. And the seismic analysis result of the bridge full model structure, which is modeled with the General Link element, has been compared with the one of the separate model structure. The present study gives. more conservative result than that of the separate model, which does not consider the dynamic behaviour of the sub-structure.

• Proceedings of the Korea Concrete Institute Conference
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• 2000.10a
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• pp.161-166
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• 2000

To save efforts for capping in the compressive strength tests of concrete, unbonded capping system has been standardized by ASTM C 1231 and AS 1012.9, respectively. These standards, however, do not sufficiently give a full detail of accessories such as steel retaining cap and rubber pad, especially hardness of rubber. Hence, without testing for sizes of steel retaining cap and rubber pad, tests for the quality control of rubber pads were conducted in detail according to Japanese studies. Based on tests, the range of hardness for rubber pad by the compressive strength(200~ 400kgf/$\textrm{cm}^2$) of concrete has been proposed and the guideline of reuses of a rubber pad is described.

• Journal of Korean Academy of Nursing
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• v.41 no.2
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• pp.236-244
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• 2011

Purpose: In this study the impact of pro-environmental behavior, well-being oriented behavior, and use of cloth menstrual pads on dysmenorrhea in Korean female adults was examined according to the theory of reasoned action. Methods: A cross-sectional study was conducted with 195 Korean female adults. Data were collected from June to August, 2010 using self-report questionnaires. Data were analyzed using t-test, one-way ANOVA, Pearson correlation coefficients, multiple regression, and logit regression with STATA 10.0. Results: Pro-environmental behavior explained 48% of well-being oriented behavior. Well-being oriented behavior explained 10% of cloth pad use. Use of cloth pad explained 4% of dysmenorrhea and 5% of menstrual pain. The path through well-being oriented behavior had a significant effect from pro-environmental behavior to cloth pad use. Conclusion: Use of cloth pad was significantly related with well-being oriented behavior, pro-environmental behavior, social influence, dysmenorrhea, and menstrual pain. The results of this study suggest that pro-environmental strategies can help health care providers diminish clients' menstrual symptoms. Nursing intervention can support pro-environmental behavioral strategies.

• Journal of the Korea Institute of Military Science and Technology
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• v.11 no.5
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• pp.107-115
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• 2008

In this paper, we have proposed a wear growth prediction method on the surface of rubber pad of track assembly installed in high-speed battle tank i.e. the automatic model updating code interfacing with commercial finite element simulation software. Also, simple and resonable geometrical, material finite element model was established to be easily updated based on the empirical threshold value of contact pressure on the contact surface. From the iterative model update and analysis results, we discovered a weak point on rubber pad surface and suggested a new design concept for improving the wear performance of track assembly.

• KIEE International Transactions on Electrophysics and Applications
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• v.2C no.5
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• pp.262-267
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• 2002

In this paper, we first studied the factors affecting the motor current (MC) signal, which was strongly affected by the systematic hardware noises depending on polishing such as pad conditioning and arm oscillation of platen and recipe, head motor. Next, we studied the end point detection (EPD) for the chemical mechanical polishing (CMP) process of shallow trench isolation (STI) with reverse moat structure. The MC signal showed a high amplitude peak in the fore part caused by the reverse meal. pattern. We also found that the EP could not be detected properly and reproducibly due to the pad conditioning effect, especially when conventional low selectivity slurry was used. Even when there was no pad conditioning effect, the EPD method could not be applied, since the measured end points were always the same due to the characteristics of the reverse moat structure with an open nitride layer.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2004.11a
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• pp.715-718
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• 2004

In this paper, we studied the characteristics of new polishing pad, which can apply W-CMP process for global planarization of multi-level interconnection structure. The hardness and density were measured as a function of groove pattern. Also, we compared the pore size through the SEM photograph. Finally, we investigated the CMP characteristics with five different kind of groove pattern sample. Through the above results, we can select optimum groove pattern, so we can expect to begin home product of polishing pad.

• 한국가시화정보학회:학술대회논문집
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• 2004.11a
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• pp.48-51
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• 2004

Chemical Mechanical Polishing(CMP) is popularly used in production of semiconductor because of large area polishing ability probability of improvement for more integrated circuit. However, present CMP processing causes some non-uniformity errors which can be critical for highly integrated circuit. Previous studies predict that flow-field of slurry during CMP can create non-uniformity, but no quantitative measurement has conducted. In this study, using PIV, slurry velocity flow-field during CMP is measured by changing the ratio of RPM of pad and carrier with tuned PIV system adequate for small room in CMP machine and Cabot's non-groove pad Epad-A100. The result show that velocity of slurry is majorly determined by pad-rpm and the ratio of between carrier and pad rpm make some changes in streamlines.