• 한국정보디스플레이학회:학술대회논문집
• /
• 한국정보디스플레이학회 2007년도 7th International Meeting on Information Display 제7권2호
• /
• pp.1253-1256
• /
• 2007

A display device combining plasma display panel (PDP) and field emission display (FED) is proposed to achieve high luminous efficiency. The device can avoid the main energy loss channels of both PDP (ion loss) and FED (low CL efficiency). $2{\sim}6$”-diagonal test panels with carbon nano-tube (CNT) electron emitter and Xenon ambient gas showed the luminous efficiency of 4.14lm/W and brightness of $263cd/m^2$ at 35V (1kHz, 1% duty), indicating that it is a good candidate for the low voltage driven, highly efficient next generation display.

• 전기학회논문지
• /
• 제56권8호
• /
• pp.1445-1449
• /
• 2007

This paper presents the DOD (Drop-On-Demand) characteristic using the electrostatic field induced inkjet printing system. In order to achieve the DOD characteristic of electrostatic field induced inkjet printing, applied the bias voltage of 1.4 kV and the pulse voltage of $2.0\;kV\;{\sim}\;2.7\;kV$ using high voltage pulse generator. Electrostatic field induced droplet ejection is directly observed using a high-speed camera and for investigated DOD characteristic, CNT ink used. The electrostatic field induced inkjet head system has DOD characteristic using pulse generator which can be applied pulse voltage. The bias voltage has a good condition which form meniscus and has micro dripping mode for small size micro droplet. Also, the droplet size decreases with increasing the applied pulse voltage. This paper shows DOD characteristic at electrostatic field induced inkjet head system, Therefore. electrostatic DOD inkjet head system will be applied industrial area comparing conventional electrostatic inkjet head system.

• 한국전기전자재료학회논문지
• /
• 제26권4호
• /
• pp.325-329
• /
• 2013

Carbon nanotubes(CNT) have excellent electrical, chemical stability and mechanical properties. These can be used in a variety of fields. MWCNT are extremely sensitive for minute changes in the ambient gas, namely, their sensing properties varies greatly with the absorption of gas such as NOx and $H_2$. We investigate the electrical properties of CNTs and make a NOx gas sensor based on Multi-walled carbon nanotubes (MWCNT) materials. We obtained the NOx gas sensor of MWCNT based on P-type Si wafer that has the resistivity of $1.667{\times}10^{-1}[{\Omega}{\cdot}cm]$. We knew that the sensitivity of sensor decreased with increasing of NOx gas concentration. And the sensitivity of sensor shows the largest value at $20^{\circ}C$. The sensitivity of sensor decrease with increasing the temperature. Also absorption energy of NOx gas molecule on the MWCNT surface decreases with increasing concentration of NOx gas.

• Steel and Composite Structures
• /
• 제30권6호
• /
• pp.493-516
• /
• 2019

This paper is dedicated to nonlinear static and free vibration analysis of Uniform Distributed Carbon Nanotube Reinforced Composite (UD-CNTRC) structures under in-plane loading. The authors have suggested an efficient six-node triangular element. Mixed Interpolation of Tensorial Components (MITC) approach is employed to alleviate the membrane locking phenomena. Moreover, the behavior of the well-known LST element is considerably improved by applying an additional linear interpolation on the strain fields. Based on the rule of mixture, the properties of CNTRC are obtained. In this study, only the uniform distributed CNTs are employed through the thickness direction of element. To achieve the natural frequencies and shape modes, the eigenvalue problem is also solved. Using Total Lagrangian Principles, large amplitude free vibration is considered based on the first normalized mode shape of structure. Different well-known plane problem benchmarks and some proposed ones are studied to validate the accuracy and capability of authors' formulations. In addition, the effects of length to the height ratio of beam, CNT's characteristics, support conditions and normalized amplitude parameter on the linear and nonlinear vibration parameters are investigated.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 2015년도 제46회 하계학술대회
• /
• pp.1515-1516
• /
• 2015

Touch panel 및 Touch screen 등의 투명전극으로 많이 사용되고 있는 ITO(Indium Tin Oxide)나 CNT(Carbon Nano Tube) 등 전도성 박막의 면저항을 쉽고 빠르게 측정하기 위하여 van der Pauw method를 이용한 면저항 측정기를 개발하였다. 이 면저항 측정기는 대면적 시료의 면저항을 측정 할 수 있어 매우 편리하다. 면저항 측정은 주로 Four Point Probe method로 측정하는 것이 일반적이나 본 연구에서는 van der Pauw method를 이용한 측정값과 Four Point Probe method로 측정한 결과를 비교한 결과 1 % 이내에서 일치하였다. 개발된 측정기의 측정 정확도는 지시값의 1.0 % 이하이고, 측정범위는 $2{\Omega}/{\square}{\sim} 5k{\Omega}/{\square}$이다.

• Composites Research
• /
• 제26권5호
• /
• pp.289-294
• /
• 2013

고분자 기지에 희석제의 첨가로 CNT 및 CB 입자의 분산성 향상 및 연질의 전극을 만들고자하였다. 희석제, CNT 및 CB 함유량에 따른 연질 전극재료의 전기적 및 기계적 특성을 평가하였다. 전극재료로서 최적의 혼합조건은 기지 (KE-12)를 기본으로 희석제 80, CNT 3.5 그리고 CB 18 (phr)이었다. 이때의 비저항 값은 73 (${\Omega}{\cdot}cm$)이었고, 인장강도와 인장탄성율 그리고 신장율은 각각 0.45 MPa, 0.21 MPa, 184%였다. 또한 최적화된 전극과 탄성체를 이용하여 간단한 구조의 구동기를 제작하여 그 특성을 평가하였다. 작동 전압 25 kV에서 탄성체 KE-12는 2.24 mm의 변위가 발생되었고, 희석제가 50 (phr) 혼합된 KE-12는 4.05mm의 변위가 발생되었다. 희석제 50 (phr) 혼합된 KE-12는 3M의 4910과 같은 탄성계수를 나타내지만, 더 높은 변위를 보였다. 동일한 재료 (KE-12)의 전극과 탄성체로 제작된 구동기는 피로수명 및 응용에 많은 장점이 있을 것으로 보인다.

• 마이크로전자및패키징학회지
• /
• 제28권1호
• /
• pp.21-29
• /
• 2021

Recently, semiconductor chips and electronic components are increasingly being used in IT devices such as wearable watches, autonomous vehicles, and smart phones. As a result, there is a growing concern about device malfunctions that may occur due to electromagnetic interference being entangled with each other. In particular, electromagnetic wave emissions from wearable or flexible smart devices have detrimental effects on human health. Therefore, flexible and transparent electromagnetic interference (EMI) shielding materials and films with high optical transmittance and outstanding shielding effectiveness have been gaining more attention. The EMI shielding films for flexible and transparent electronic devices must exhibit high shielding effectiveness, high optical transmittance, high flexibility, ultrathin and excellent durability. Meanwhile, in order to prepare this EMI shielding films, many materials have been developed, and results regarding excellent EMI shielding performance of a new materials such as carbon nano tube (CNT), graphene, Ag nano wire and MXene have recently been reported. Thus, in this paper, we review the latest research results to EMI shielding films for flexible and transparent device using the new materials.

• Advances in nano research
• /
• 제8권4호
• /
• pp.307-322
• /
• 2020

In this article, free vibration of double-walled carbon nanotubes (DWNT) based on nonlocal Kelvin's model have been investigated. For this purpose, a nonlocal Kelvin's model is established to observe the small scale effect. The wave propagation is employed to frame the governing equations as eigenvalue system. The influence of nonlocal parameter subjected to different end supports has been overtly examined. The new set of inner and outer tubes radii investigated in detail against aspect ratio. The influence of boundary conditions via nonlocal parameter is shown graphically. Due to small scale effect fundamental frequency ratio decreases as length to diameter ratio increases. Small scale effect becomes negligible on all end supports for the higher values of aspect ratio. With the smaller inner tube radius double-walled CNT behaves more sensitive towards nonlocal parameter. The results generated furnish the evidence regarding applicability of nonlocal model and also verified by earlier published literature.

• 한국산학기술학회논문지
• /
• 제16권5호
• /
• pp.3627-3632
• /
• 2015

고분자 전해질 막 연료전지의 분리판 용 흑연/폴리프로필렌(PP)/액정고분자 (LCP) 복합소재의 기계적, 유변학 특성 및 전기전도도에 관하여 연구하였다. 저분자량 PP를 바인더로 사용하는 경우 다른 열가소성 고분자와 비교하여 상당히 높은 전기 전도도를 보임을 확인하였는데 이는 점도가 낮은 PP에 의해 흑연 입자의 분산이 향상되어 나타난 결과임을 확인할 수 있었다. 또한 탄소나노튜브를 소량 첨가하면 복합재료의 전기전도도가 크게 증가하였고 산처리를 하여 산소 관능기를 포함한 탄소나노튜브를 첨가했을 때에는 전기전도도의 증가가 거의 없었다. 이로부터 탄소나노튜브는 비극성 고분자와 친화도가 높음을 알 수 있었다. 저분자량 PP를 바인더로 사용하였을 때는 복합재료의 점도가 사출성형이 가능할 정도로 낮은 것을 관찰할 수 있었다. 그러나 기계적인 강도는 다른 고분자에 비해 현저히 낮았다. 이를 보강하기 위하여 LCP를 혼합하여 복합재료를 제조한 결과 전반적인 물성 밸런스가 잘 맞는 복합재료를 얻을 수 있었다.

• 한국전기전자재료학회논문지
• /
• 제26권9호
• /
• pp.707-711
• /
• 2013

Carbon nanotubes(CNT) has strength and chemical stability, greatly conductivity characteristics. In particular, MWCNT (multi-walled carbon nanotubes) show rapidly resistance sensitive for changes in the ambient gas, and therefore they are ideal materials to gas sensor. So, we fabricated NOx gas sensors structured MOS-FET using MWCNT (multi-walled carbon nanotubes) material. We investigate the change resistance of NOx gas sensors based on MOS-FET with ultra lean NOx gas concentrations absorption. And NOx gas sensors show sensitivity on the change of gate-source voltage ($V_{gs}=0[V]$ or $V_{gs}=3.5[V]$). The gas sensors show the increase of sensitivity with increasing the temperature (largest value at $40^{\circ}C$). On the other hand, the sensitivity of sensors decreased with increasing of NOx gas concentration. In addition, We obtained the adsorption energy($U_a$), $U_a$ = 0.06714[eV] at the NOx gas concentration of 8[ppm], $U_a$ = 0.06769[eV] at 16[ppm], $U_a$ = 0.06847[eV] at 24[ppm] and $U_a$ = 0.06842[eV] at 32[ppm], of NOx gas molecules concentration on the MWCNT gas sensors surface with using the Arrhenius plots. As a result, the saturation phenomena is occurred by NOx gas injection of concentration for 32[ppm].