• Title/Summary/Keyword: Stripping process

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Shield Wire Stripping of Micro Coaxial Cable for Medical Device Using Laser (레이저를 이용한 의료기기용 미세 동축케이블의 실드선 탈피)

  • Lee, Jeong-Wan;Kim, Jung-Hoon
    • Journal of the Korean Society for Precision Engineering
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    • v.26 no.9
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    • pp.64-71
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    • 2009
  • Recently as ultrasonic medical devices are gradually developed, many of those require smaller and more precision coaxial cables in the probe. So, the use of micro coaxial cable becomes an efficient solution for ultrasonic machine. However, there are many difficulties in stripping micro coaxial cable by traditional mechanical process. In this paper we use the Nd:YAG laser for the efficient striping of conduct wire of cable. Through some experiments, we found that there is a new possibility in the proposed method. Also, we propose a pre-process of the cable before stripping in order to enhance the performance.

Characteristics of the Oxygen Plasma and Its Application to Photoresist Stripping (산소 플라즈마의 특성과 포토레지스트 제거에의 응용)

  • Whang, Ki Woong;Lee, Jong Duk;Kim, Joung Ho
    • Journal of the Korean Institute of Telematics and Electronics
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    • v.24 no.1
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    • pp.73-78
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    • 1987
  • The physical mechanism of a RF discharge used in photoresist stripping and etching process are not well understood and, plasma reactor design and the determination of optimum operating coditions are done largely on empirical basis. We analyzed the discharge process through the measurement of plasma characteristics and applied out results tothe analysis of the photoresist stripping. We investigated the effects of plasma electron density, neutral oxygen gas pressure and electrode temperature on the stripping rates and related their effects with the characteristics of plasma.

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Vacuum Stripping of $CO_2$ from Aqueous MEA Solutions Using PDMS-PE Composite Membrane Contactor (MEA 수용액으로부터 PDMS-PE 복합막 접촉기를 이용한 이산화탄소 감압탈거)

  • Kim, Jeong-Hoon;Ahn, Hyo-Seong;Kim, Jeong-Hoon
    • Membrane Journal
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    • v.22 no.1
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    • pp.46-53
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    • 2012
  • Low-temperature carbon dioxide stripping by a vacuum membrane stripping technology was studied as a substitute for the stripping process in a conventional aqueous amine process. Composite membranes with $5{\mu}m$ thickness of PDMS (polydimethylsiloxane) dense layer on a PE (polyethylene) support layer were prepared by a casting method and used as a membrane contactor for $CO_2$ stripping. Aqueous amine solutions of 30 wt% MEA (monoethanolamine) were used as absorbents. $CO_2$ flux was examined under various operating conditions by varying the vacuum pressure (60~360 mmHg (abs.)), stripping temperature ($25{\sim}80^{\circ}C$), $CO_2$ loading (0.5~0.7). $CO_2$ stripping flux increased with increasing temperature and $CO_2$ loading as well as decreasing vacuum pressure. PDMS-PE composite membrane has stability for vacuum stripping process compared with PTFE porous membrane.

A Study on the Characteristics and Cleanliness of Fluidic Strip Process of Environment-Friendly Aqueous Stripper (친환경 수계 박리액의 유동박리 공정 특성 및 청정성 연구)

  • Lee, Ki-Seong;Lee, Jaeone;Kim, Young Sung
    • Clean Technology
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    • v.24 no.3
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    • pp.175-182
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    • 2018
  • In this research, we investigated the cleanliness by optimizing the water content of the aqueous stripper in fluidic strip process. The stripping properties of the photoresist with optimized aqueous stripper were compared with the commercial organic stripper. The stripping performance was evaluated by electrical and optical characteristics on the surface of the transparent electrode that compare with stripped the transparent electrode surface and the rare surface before patterning by the photoresist. As a result of the photoresist stripping process of the organic stripper and the aqueous stripper optimized for water content, the aqueous stripper exhibited better electrical and optical characteristics than the organic stripper. In the case of the fluidic strip process with organic stripper, the photoresist dissolves in the stripper solution during stripping which can cause re-adsorption by contamination. Whereas that the aqueous stripper under development seems to decrease the photoresist dissolution in the stripper solution. Because the cyclodextrin contained in the stripper captures organic photoresist into hall of cyclodextrin which stripped through swelling and tearing. The photoresist residue captured by the cyclodextrin can be filtered. After the fluidic stripping process by different chemical stripping mechanism, the cleanliness of the organic stripper and aqueous stripper was compared and analyzed.

Hydrogen Plasma Characteristics for Photoresist Stripping Process in a Cylindrical Inductively Coupled Plasma

  • Yang, Seung-Kook;Cho, Jung Hee;Lee, Seong-Wook;Lee, Chang-Won;Park, Sang-Jong;Chae, Hee-Sun
    • JSTS:Journal of Semiconductor Technology and Science
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    • v.13 no.4
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    • pp.387-394
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    • 2013
  • As the feature size of integrated circuits continues to decrease, the challenge of achieving an oxidation-free exposed layer after photoresist (PR) stripping is becoming a critical issue for semiconductor device fabrication. In this article, the hydrogen plasma characteristics in direct plasma and the PR stripping rate in remote plasma were studied using a $120{\Phi}$ cylindrical inductively coupled plasma source. E mode, H mode and E-H mode transitions were observed, which were defined by matching the $V_{rms}$ and total impedance. In addition, the dependence of the E-H mode transition on pressure was examined and the corresponding plasma instability regions were identified. The plasma density and electron temperature increased gradually under the same process conditions. In contrast, the PR stripping rate decreased with increasing proportion of $H_2$ gas in mixed $H_2/N_2$ plasma. The decrease in concentration of reactive radicals for the removal of PR with increasing $H_2$ gas flow rate suggests that NH radicals have a dominant effect as the main volatile product.

ISM truncation due to ram pressure stripping: Comparisons of Theoretical Predictions and Observations

  • Lee, Seona;Sheen, Yun-Kyeong;Yoon, Hyein;Chung, Aeree;Jaffe, Yara
    • The Bulletin of The Korean Astronomical Society
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    • v.44 no.1
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    • pp.77.1-77.1
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    • 2019
  • It has been proposed by Gunn & Gott (1972) that galaxies may lose their interstellar gas by ram pressure due to the dense intra-cluster medium while falling to the cluster potential. The observational evidence for this process, which is known as ram pressure stripping, is increasing, and it is believed to be one of the key environmental effects that can dramatically change the star formation activity of galaxies and hence their evolution. Intriguingly however, some cases with clear signs of ram pressure stripping are found in the environment which betrays our expectations (e.g. large clustercentric distances), and our understandings to the detailed working principle behind ram pressure stripping seem to be still lacking. As one of the ways to gain more theoretical insights into the conditions for ram pressure stripping process, we have been comparing the gas truncation radius which is predicted based on the simple Gunn & Gott's prescription with what is actually observed in a sample of carefully selected Virgo galaxies. In this work, we present the results of our comparisons between the theoretically predicted truncation radius and the observationally measured truncation radius for individual galaxies in the sample and discuss which additional conditions are needed in order to fully understand the observations.

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A Study on Shield Wire Stripping of Micro Coaxial Cable for Medical Device Using Nd:YAG Laser (Nd:YAG 레이저를 이용한 의료기기용 마이크로 동축케이블의 실드선 탈피에 관한 연구)

  • Lee, Jeong-Wan;Kim, Jung-Hoon
    • Journal of Industrial Technology
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    • v.26 no.B
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    • pp.35-41
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    • 2006
  • Recently, as ultrasonic medical devices are gradually developed, many of those requires smaller and more precision coaxial cables in probe. So, the use of micro coaxial cable becomes an efficient solution for ultrasonic machine. However, there are many difficulties in stripping micro coaxial cable by traditional mechanical process. In this paper, we use the Nd-YAG laser for the efficient stripping of conduct wire of cable. We propose a new method to strip the shield wire of micro coaxial cable. Through some experiments, we found that there is a new possibility in the proposed method. Also, in order to enhance the performance, we propose a preprocess of the cable before stripping.

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Ram pressure stripping conditions : Theory vs. Observation

  • Lee, Seona;Sheen, Yun-Kyeong;Yoon, Hyein;Jaffe, Yara;Chung, Aeree
    • The Bulletin of The Korean Astronomical Society
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    • v.45 no.1
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    • pp.33.1-33.1
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    • 2020
  • Ram pressure stripping (RPS) which is known to be one of the key effects that can remove the interstellar gas in the dense environment, can be described as a simple momentum transfer relation (Gunn & Gott 1972). However, it has been suggested that the actual gas stripping process is likely more complicated than Gunn & Gott's prescription due to the complexity of gas physics such as compression, cooling and heating. By comparing the gas truncation radius predicted by theory with the stripping radius measured from the HI observation of Virgo cluster galaxies, we attempt to verify how well the RPS process can be understood by momentum transfer alone. Among the sample of galaxies undergoing active RPS, we generally find a good agreement between what is predicted and what is observed within the measurement uncertainties. However, those galaxies with the signs of other environmental effects than RPS such as tidal interaction, and/or the ones likely at relatively early or later stages of RPS show some offsets between the theory and the observation. These results imply that Gunn & Gott's formula works reasonably well in a broad sense when the RPS is a dominant process and the surrounding environment at the current location of the sample can be well defined. Otherwise, the impact of the second mechanism, as well as the (current and past) environment of the sample, should be more carefully reviewed to assess the impact of RPS on galaxy evolution.

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A study on the dither-stripping with dither motion sensor of a ring laser gyroscope (링레이저 자이로의 몸체진동 검출센서를 이용한 dither-stripping 연구)

  • Sim, Gyu Min;Im, Hu Jang
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.31 no.5
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    • pp.63-71
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    • 2003
  • In this paper we dicuss the dither-stripping methods by V-F(voltage to frequency) conversion of the output of angular velocity sensor which is for detecting the dither motion of the ring laser cavity. In this case, it is very important to evaluate the pulse-to-pulse scale factor between the ring lase output pulse and V-F output pulse, and also to compensate the zero offset of the V-F output pulse. In the case of the dither-stripping by the V-F conversion of angular velocity sensor output, there is a big angle uncertainty in the process of compensating the zero offset due to the dither noise for compensating the V-F output. By differential, the phase of the V-F output is changed. So, to compensate it, we change 90deg of the phase of angular velocity sensor output and delay half sampling time of the phase of ring laser output in advance. In this case the pulse-to-pulse scale factor can be evaluated by the standard deviation of each pulse. We can get the good result of the dither-stripping output by this angle differential method.

A Study on the Decompressed Ammonia Stripping from Ammonia Contained Wastewater (폐수의 감압 암모니아 탈기에 관한 연구)

  • 신대윤;오유경
    • Journal of Environmental Health Sciences
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    • v.27 no.1
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    • pp.93-99
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    • 2001
  • This study aims at finding out pertinent reaction conditions for treating high concentration ammonia contained in N-chemical factory wastewater with decompressed ammonia stripping method that was designed. And it also tries to investigate adsorption capability of removed ammonia to soil. The results from experiments are as follows ; 1. The removal rate of N $H_3$-N of synthetic wastewater was under 85% at pH 10 with decompressed ammonia stripping method. The reaction time in pressure 360 mmHg at pH 11 and 12 was shorter than in 460 mmHg, and the removal rate of N $H_3$-N with decompressed ammonia stripping method at 9$0^{\circ}C$ was 11~15% higher than air stripping 2. The optimum conditions for decompressed ammonia stripping with synthetic sample were shown as pH 12, temperature 9$0^{\circ}C$, internal reaction pressure 460 mmHg and reaction time 50 minutes. These conditions were applied to treat the wastewater containing organic-N 290.5mg/$\ell$, N $H_3$-N 168.9mg/$\ell$, N $O_2$-N 23.2mg/$\ell$, N $O_3$-N 252.4mg/$\ell$, T-N 735mg/$\ell$. Organic-N turned out to be removed 60%, the removal rate of N $H_3$-N IS 94%, T-N is 50%. But N $O_2$-N and N $O_3$-N were increased with 7.8% and 14.9% respectively. 3. The CO $D_{Sr}$ removal rate in decompressed ammonia stripping reaction was 42% and S $O_4$$^{2-}$ was removed 8.2%. It was turned out caused with higher pH and thermolysis. 4. In soil adsorption of ammonia desorbed from the decompressed stripping process of wastewater, the recovery rate was 76% in wet soil.

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