• Title/Summary/Keyword: static charge

Search Result 117, Processing Time 0.025 seconds

Properties of Anti-static Material Using Carbon Nanotube (탄소나노튜브를 이용한 폴리우레탄 코팅소재의 대전방지성)

  • Kim, Jong-Won;Song, Sun-Hye;Yoon, Seok-Han;Song, Byung-Kab;Chu, Gyo-Jin;An, Hun-Ju
    • Textile Coloration and Finishing
    • /
    • v.19 no.4
    • /
    • pp.26-31
    • /
    • 2007
  • Nanocomposite resin(PUD-CNT) composed of Carbon nanotube(CNT) and Polyurethane Dispersion (PUD) was prepared by different contents of CNT($0{\sim}5%$). PUD-CNT was coated on samples, and their electrical conductivity was investigated. With increasing CNT content, static change, half life and surface resistance decreased. Composites having 5% CNT showed $10^9{\Omega}/cm$(surface resistance), and 40V (stactic charge). Respectively, From this results, PUD-CNT can be used as a antistatic material.

Field Control Type Electrostatic Charge Neutralizer (전계 제어형 정전하 중화장치)

  • Jeong, Seok-Hwan;Lee, Dae-Hui;Mun, Jae-Deok
    • The Transactions of the Korean Institute of Electrical Engineers C
    • /
    • v.48 no.6
    • /
    • pp.469-474
    • /
    • 1999
  • Methods and systems to remove static electricity are requested in the field of industry because the static electricity causes a flammable gas explosion or fire and a reduction of production rate in manufacturing semiconductor devices and so on. This paper is a basic study about a new structure of electrode system to control the quantities of generated ions and to solve the problem of dust attachment to needle electrode. In addition, a new type field controlled electrostatic charge neutralizer was proposed, and it could control the electric field in the end of the needle electrode by controlling the voltage of the third electrode around the tip of the needle electrode. As aresult, it was possible to control the quantities of generated ion by controlling the electric field in the needle electrode with the third electrode, which shows the possibilities to solve the nonequilibrium of generated ions in ac power source and the problem of the dust in the needle electrode.

  • PDF

Analysis of Accelerated Soft Error Rate for Characteristic Parameters on Static RAM (정적 RAM 특성 요소에 의한 소프트 에러율의 해석)

  • Gong, Myeong-Kook;Wang, Jin-Suk;Kim, Do-Woo
    • The Transactions of the Korean Institute of Electrical Engineers C
    • /
    • v.55 no.4
    • /
    • pp.199-203
    • /
    • 2006
  • This paper presents an ASER (Accelerated Soft Error Rate) integral model. The model is based on the facts that the generated EHP/s(electron hole pairs) are diminished after some residual range of the incident alpha particle, where residual range is a function of the incident angle and the capping layer thickness over the semiconductor junction. The ASER is influenced by the flux of the alpha particles, the junction area ratio, the alpha particle incident angle when the critical charge is same as the collected charge, and the sizes of the alpha source and the chip. The model was examined with 8M static RAM samples. The measured ASER data showed good agreement with the calculated values using the model. The ASER decreased exponentially with respect to the operational voltage. As the capping layer thickness increases up to $16{\mu}m$, the ASER increases, and after that thickness, the ASER decreases. The ASER increased as the depth of BNW increased from $0{\mu}m\;to\;4{\mu}m$. and then saturated. The ASER decreased as the node capacitance increased from 2fF to 5fF.

The Effect of Needle Electrode in the Static Charge Elimination Methodes for Streaming-Electrification Insulating Oil (유동대전된 절연유의 제전방식중 침전극 삽입의 영향 (IV))

  • Chung, K.H.;Lim, H.C.;Kim, Y.W.;Hwang, M.W.;Paek, Y.C.;Lee, D.C.
    • Proceedings of the KIEE Conference
    • /
    • 1995.07c
    • /
    • pp.1202-1204
    • /
    • 1995
  • In this paper, We investigated a charge elimination by using a needle electrode in order to prevent the electrification phenomena of insulating oil flowing by force at the internal transformer. In our experiment, We used Acryle and Teflon as the material of charge reducer and measured each of their streaming current and needle electrode current. As a result of experiment, We can explain that the current of needle electrode increase in proportion to insulation of charge reducer.

  • PDF

Damage and Failure Characteristics of Semiconductor Devices by ESD (ESD에 의한 반도체소자의 손상특성)

  • 김두현;김상렬
    • Journal of the Korean Society of Safety
    • /
    • v.15 no.4
    • /
    • pp.62-68
    • /
    • 2000
  • Static electricity in electronics manufacturing plants causes the economic loss, yet it is one of the least understood and least recognized effects haunting the industry today. Today's challenge in semiconductor devices is to achieve greater functional density pattern and to miniaturize electronic systems of being more fragile by electrostatic discharges(ESD) phenomena. As the use of automatic handling equipment for static-sensitive semiconductor components is rapidly increased, most manufacturers need to be more alert to the problem of ESD. One of the most common causes of electrostatic damage is the direct transfer of electrostatic charge from the human body or a charged material to the static-sensitive devices. To evaluate the ESD hazards by charged human body and devices, in this paper, characteristics of electrostatic attenuation in domestic semiconductor devices is investigated and the voltage to cause electronic component failures is investigated by field-induced charged device model(FCDM) tester. The FCDM simulator provides a fast and inexpensive test that faithfully represents ESD hazards in plants. Also the results obtained in this paper can be used for the prevention of semiconductor failure from ESD hazards.

  • PDF

Electrostatic Discharge Energy Estimation of the Charged Human Body by the Rompe-Weisel Model (Rompe-Weisel Model에 의한 대전 인체의 정전기 방전 에너지 평가)

  • 이종호;김두현;강동규
    • Journal of the Korean Society of Safety
    • /
    • v.18 no.3
    • /
    • pp.54-59
    • /
    • 2003
  • The discharge energy by electrostatic discharge of the charged human body is calculated under the assumption that the stored charge is dissipated completely. However, it is well-known that the charge is slightly remained after electrostatic discharge. Therefore, The Rompe-Weisel model of the discharge analysis, which has somewhat more of a physical justification than the conventional energy equation, is proposed. It is proposed that the electrical conductivity of the arc should be proportional to the energy density transferred to it by Ohmic dissipation. For the electrostatic discharge energy analysis, the Rompe-Weisel model was compared by quasi static analysis. As a consequence, a study on a reliable energy evaluation based on simulation models during electrostatic discharge is carried out in this paper and is adopted to estimate the explosion hazards of flammable gases.

A Review of SiC Static Induction Transistor (SIT) Development for High-Frequency Power Amplifiers

  • Sung, Y.M.;Casady, J.B.;Dufrene, J.B.
    • KIEE International Transactions on Electrophysics and Applications
    • /
    • v.11C no.4
    • /
    • pp.99-106
    • /
    • 2001
  • An overview of Silicon Carbide (SiC) Static Induction Transistor (SIT) development is presented. Basic conduction mechanisms are introduced and discussed, including ohmic, exponential, and space charge limited conduction (SCLC) mechanisms. Additionally, the impact of velocity saturation and temperature effects on SCLC are reviewed. The small-signal model, breakdown voltage, power density, and different gate structures are also discussed, before a final review of published SiC SIT results. Published S-band (3-4 GHz) results include 9.5 dB of gain and output power of 120 W, and L-band (1.3 GHz) results include 400 W output power, 7.7 dB of gain, and power density of 16.7 W/cm.

  • PDF

Electrostatic Electrification Relaxation Properties of Polyester Rayon Non-woven Fabric due to Weight Variation (중량변화에 의한 폴리에스터 레이온 부직포의 정전기 대전 완화특성)

  • Lee, Sung-Ill;Park, Yong-Soon
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
    • /
    • v.24 no.12
    • /
    • pp.977-981
    • /
    • 2011
  • Non-wovens polyester rayon samples were manufactured, and the electrification properties of electrostatics were measured for three different samples (15 g/$m^2$, 25 g/$m^2$, and 40 g/$m^2$) with the environmental settings of temperature (20~40$^{\circ}C$) and humidity (40~90%). The conclusions are as follows. Heavy sample generated more static electricity when the temperature was constant. The static electricity decreased slowly when the humidity is less than 70%, while it sharply decreased over 70% humidity condition. For non-woven polyester rayon, static charge decreased as temperature and humidity increased. As the weight increased, less time were taken for the electrification voltage to drop to the half.

The Study on the Design of Static Flip-Flop Circuits for the Driving of Matrix Type Electrodes (매트릭스형 전극 구동용 스태틱 플립플롭 회로의 설계기법에관한 연구)

  • 최선정;정기현;김종득
    • Journal of the Korean Institute of Telematics and Electronics A
    • /
    • v.30A no.7
    • /
    • pp.75-81
    • /
    • 1993
  • In this paper, New type of Static Edge Triggered D Flip-Flop Circuits which are effective for the sequencial selecting and addressing of Matrix type Electrodes being applied to Flat Display Devices is proposed by the Design Technique using the Transmission Characteristics of Feedback Transistors and Charge Back Up Function. These Circuits composed of 2-4 less transistors in number than Conventional Static D Flip Flop's have some advantages that the Maximum Transition Time of Clock Signals allowed is increased by 100-450 times more than that of the Conventional circuit at 100KHz Clock Frequence and Circuit Safety is much increased by making the wider ranges, 1-4V, of Clock Levelas a Non-operating periods than 3-3.2V ranges in case of the Conventional Circuit at 10MHz clock frequence. By these advantages, These circuits can be very effectively used in case that clock signal has long transition time, especially on the low frequency operation.

  • PDF

Selectivity and structural integrity of a nanofiltration membrane for treatment of liquid waste containing uranium

  • Oliveira, Elizabeth E.M.;Barbosa, Celina C.R.;Afonso, Julio C.
    • Membrane and Water Treatment
    • /
    • v.3 no.4
    • /
    • pp.231-242
    • /
    • 2012
  • The performance of a nanofiltration membrane for treatment of a low-level radioactive liquid waste was investigated through static and dynamic tests. The liquid waste ("carbonated water") was obtained during conversion of $UF_6$ to $UO_2$. In the static tests membrane samples were immersed in the waste for 24, 48 or 72 h. The transport properties of the samples (hydraulic permeability, permeate flow, selectivity) were evaluated before and after immersion in the waste. In the dynamic tests the waste was permeated in a permeation flow front system under 0.5 MPa, to determine the selectivity of NF membranes to uranium. The surface layer of the membrane was characterized by zeta potential, field emission microscopy, atomic force spectroscopy and infrared spectroscopy. The static test showed that the pore size distribution of the selective layer was altered, but the membrane surface charge was not significantly changed. 99% of uranium was rejected after the dynamic tests.