• 제목/요약/키워드: Carbon ion beam

검색결과 140건 처리시간 0.021초

Carbon Ion Therapy: A Review of an Advanced Technology

  • Kim, Jung-in;Park, Jong Min;Wu, Hong-Gyun
    • 한국의학물리학회지:의학물리
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    • 제31권3호
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    • pp.71-80
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    • 2020
  • This paper provides a brief review of the advanced technologies for carbon ion radiotherapy (CIRT), with a focus on current developments. Compared to photon beam therapy, treatment using heavy ions, especially a carbon beam, has potential advantages due to its physical and biological properties. Carbon ion beams with high linear energy transfer demonstrate high relative biological effectiveness in cell killing, particularly at the Bragg peak. With these unique properties, CIRT allows for accurate targeting and dose escalation for tumors with better sparing of adjacent normal tissues. Recently, the available CIRT technologies included fast pencil beam scanning, superconducting rotating gantry, respiratory motion management, and accurate beam modeling for the treatment planning system. These techniques provide precise treatment, operational efficiency, and patient comfort. Currently, there are 12 CIRT facilities worldwide; with technological improvements, they continue to grow in number. Ongoing technological developments include the use of multiple ion beams, effective beam delivery, accurate biological modeling, and downsizing the facility.

Alignment Effects for Nematic Liquid Crystal on a New Diamond-like Carbon Layer

  • Seo, Dae-Shik;Jo, Yong-Min;Hwang, Jeoung-Yeon;Lee, Sang-Keuk
    • Transactions on Electrical and Electronic Materials
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    • 제3권2호
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    • pp.1-5
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    • 2002
  • Alignment effects for nematic liquid crystal (NLC) and electro-optical (EO) characteristics of the ion beam (IB) aligned twisted nematic (TN)-liquid crystal display (LCD) with oblique ion beam exposure on the diamond-like carbon (DLC) thin film surface were studied. A high pretilt angle of 3.5$^{\circ}$ in NLC by ion beam exposure on the DLC thin film layer can be measured. An excellent voltage-transmittance (V-T) curve of the ion beam aligned TN-LCD was observed with oblique ion beam exposure on the DLC thin film surface for 1 min. Also, a faster response time for the ion beam aligned TN-LCD with oblique ion beam exposure on the DLC thin film surface for 1 min can be achieved.

DLC 박막을 이용한 Ion Beam 배향 TN 셀의 전기광학특성에 관한 연구 (A Study on Electro-Optical Characteristics of the Ion Beam Aligned TN Cell on the DLC Thin Film)

  • 황정연;조용민;노순준;이대규;백홍구;서대식
    • 한국전기전자재료학회논문지
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    • 제15권8호
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    • pp.726-730
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    • 2002
  • Electro-optical (EO) performances of the ion beam (IB) aligned twisted-nematic (TN)-liquid crystal display (LCD) with ion beam exposure on the new diamond-like carbon (DLC) thin film surface were investigated. A good voltage-transmittance (V-T) curve of the ion beam aligned TN-LCD with oblique ion beam exposure on the DLC thin film surface for 1 min was observed. Also, the fast response time of the ion beam aligned TN-LCD with oblique ion beam exposure on the DLC thin film surface for 1 min can be achieved. Finally, the residual DC voltage of the ion beam aligned TN-LCD on the DLC thin film surface is almost the same as that of the rubbing aligned TN-LCD on a polyimide (Pl) surface.

EO Performances of the Ion Beam Aligned TN-LCD on a Carbon Nitride Thin Film Surface

  • Park, Chang-Joon;Hwang, Jeoung-Yeon;Kang, Hyung-Ku;Seo, Dae-Shik;Ahn, Han-Jin;Kim, Jong-Bok;Kim, Kyung-Chan;Baik, Hong-Koo
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2004년도 Asia Display / IMID 04
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    • pp.1121-1124
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    • 2004
  • Carbon Nitride exhibits high electrical resistivity and thermal conductivity that are similar to the properties shown by diamond-like carbon (DLC) films. These diamond-like transport properties in Carbon Nitride come in a material consisting of $sp^2$-bonded carbon versus the $sp^3$-carbon of DLC. The diamond-like properties and nondiamond-like bonding make NDLC an attractive candidate for applications. Liquid crystal (LC) alignment capabilities with ion beam exposure on carbon nitride thin films and Electro-Optical (EO) performances of the ion-beam aligned twisted nematic liquid crystal display (TN-LCD) with oblique ion beam exposure on the Carbon Nitride thin film surface were studied. An excellent uniform alignment of the nematic liquid crystal (NLC) alignment with the ion beam exposure on the Carbon Nitride thin films was observed. In addition, the good EO properties of the ion-beam-aligned TN-LCD were achieved. Finally, we achieved the residual DC property of the ion-beam- aligned TN-LCD on the Carbon Nitride thin film.

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The Effects of Negative Carbon Ion Beam Energy on the Properties of DLC Film

  • Choi, Bi-Kong;Choi, Dae-Han;Kim, Yu-Sung;Jang, Ho-Sung;Lee, Jin-Hee;Yoon, Ki-Sung;Chun, Hui-Gon;You, Young-Zoo;Kim, Dae-Il
    • 한국표면공학회지
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    • 제39권3호
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    • pp.105-109
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    • 2006
  • The effects of negative carbon ion beam energy on the bonding configuration, hardness and surface roughness of DLC film prepared by a direct metal ion beam deposition system were investigated. As the negative carbon ion beam energy increased from 25 to 150 eV, the $sp^3$ fraction of DLC films was increased from 32 to 67%, while the surface roughness was decreased. The films prepared at 150 eV showed the more flat surface morphology of the film than that of the film prepared under another ion beam energy conditions. Surface roughness of DLC film varied from 0.62 to 0.22 nm with depositing carbon ion beam energy. Surface nano-hardness increased from 12 to 57 Gpa when increasing the negative carbon ion beam energy from 25 to 150 eV, and then decreased when increasing the ion beam energy from 150 to 200 eV.

EO Performances for Ion-beam Aligned TN-LCD on a DLC Thin Film Layer

  • Jo, Yong-Min;Hwang, Jeoung-Yeon;Seo, Dae-Shik;Lee, Sang-Keuk
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2002년도 춘계학술대회 논문집 디스플레이 광소자 분야
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    • pp.118-120
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    • 2002
  • Electro-optical (EO) characteristics of the ion beam (IB) aligned twisted nematic (TN)-liquid crystal display (LCD) with oblique ion beam exposure on the diamond-like carbon (DLC) thin film surface were studied. An excellent voltage-transmittance (V-T) curve of the ion beam aligned IN-LCD was observed with oblique ion beam exposure on the DLC thin film surface for I min. Also, a faster response time for the ion beam aligned TN-LCD with oblique ion beam exposure on the DLC thin film surface for 1 min can be achieved.

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Preparation of photoresist-derived carbon micropatterns by proton ion beam lithography and pyrolysis

  • Nam, Hui-Gyun;Jung, Jin-Mook;Hwang, In-Tae;Shin, Junhwa;Jung, Chang-Hee;Choi, Jae-Hak
    • Carbon letters
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    • 제24권
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    • pp.55-61
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    • 2017
  • Carbon micropatterns (CMs) were fabricated from a negative-type SU-8 photoresist by proton ion beam lithography and pyrolysis. Well-defined negative-type SU-8 micropatterns were formed by proton ion beam lithography at the optimized fluence of $1{\times}10^{15}ions\;cm^{-2}$ and then pyrolyzed to form CMs. The crosslinked network structures formed by proton irradiation were converted to pseudo-graphitic structures by pyrolysis. The fabricated CMs showed a good electrical conductivity of $1.58{\times}10^2S\;cm^{-1}$ and a very low surface roughness.

집속이온빔을 이용한 탄소나노튜브 팁의 조작 (Manipulation of Carbon Nanotube Tip Using Focused Ion Beam)

  • 윤여환;박준기;한창수
    • 한국정밀공학회지
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    • 제23권12호
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    • pp.122-127
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    • 2006
  • This paper reports on the development of carbon nanotube tip modified with focused ion beam(FIB). We used an electric field which causes dielectrophoresis, to align and deposit CNTs on a metal-coated canning Probe Microscope (SPM) tip. Using the CNT attached SPM tip, we have obtained an enhanced resolution and wear property compared to that from the bare silicon tip through the scanning of the surface of the bio materials. The carbon nanotube tip was aligned toward the source of the ion beam allowing their orientation to be changed at precise angles. By this technique, metal coated carbon nanotube tips that are several micrometer in length are prepared for SPM.

NDLC 박막 위에 Ion Beam 배향한 TN-LCD의 전기광학특성 (EO Characteristics of the ion Beam Aligned TN-LCD on the NDLC Thin Film Surface)

  • 박창준;황정연;강형구;안한진;김경찬;김종복;백홍구;서대식
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2004년도 하계학술대회 논문집 Vol.5 No.2
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    • pp.1054-1057
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    • 2004
  • The nitrogenated diamond-like carbon (NDLC) exhibits high electrical resistivity and thermal conductivity that are similar to the properties shown by diamond-like carbon (DLC) films. These diamond-like transparent properties in NDLC come in a material consisting of $sp^2$-bonded carbon versus the $sp^3$-carbon of DLC. The diamond-like properties and nondiamond-like bonding make NDLC an attractive candidate for applications. Liquid crystal (LC) alignment capabilities with ion beam exposure on NDLC thin films and electro-optical (EO) performances of the ion-beam-aligned twisted nematic liquid crystal display (TN-LCD) with oblique ion beam exposure on the NDLC thin film surface were studied. An excellent uniform alignment of the nematic liquid crystal (NLC) alignment with the ion beam exposure on the NDLC thin films was observed. In addition, it can be achieved that the good EO properties of the ion-beam-aligned TN-LCD. Finally, we will present the residual DC property of the ion-beam-aligned TN-LCD on the NDLC thin film surface.

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a-C:H 박막의 물성 변화에 따른 액정 배향 특성에 관한 연구 (A study on liquid crystal alignment characteristics by the properties of hydrogenated amorphous carbon thin films)

  • 이대규;노순준;백홍구;황정연;조용민;서대식
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2002년도 하계학술대회 논문집 Vol.3 No.2
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    • pp.839-844
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    • 2002
  • This letter focuses on the liquid crystal alignment characteristics according to the properties of hydrogenated amorphous carbon(a-C:H) thin film deposited by RPECVD(Remote Plasma Enhanced Chemical Vapor Deposition) method using $C_2H_2$ and He gases. The properties of the deposited thin films were controlled by the ion beam irradiation time and ion beam energy. The results show that not ion beam energy but ion beam irradiation time plays an important role in the properties of a-G:H thin films. As the ion beam irradiation time increases, not only the sp2 concentration in a-G:H thin films but also liquid crystal pretilt angle was varied.

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