• Title/Summary/Keyword: micromachining

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Fabrication of multi-layered electrostatic lens by mixed micromachining technology (혼합 마이크로머시닝기술을 이용한 다층전극구조의 정전렌즈 제작)

  • 이영재;전국진
    • Journal of the Korean Institute of Telematics and Electronics D
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    • v.35D no.9
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    • pp.48-53
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    • 1998
  • We have fabricated electrostatic lens with novel structure by mixing surface- and bulk-micromachining technology. Polysilicon was used for both the structure and sacrificial layer, and the structure layer was passivated with thermal oxide in order not to be attacked during the silicon wet etching. Compared with conventional electrostatic lens used in microcolumn, this device has the advantages in ; 1) hole alignment, throughput, reliability, damage of lens, 2) the possibility of arrayed lithography through the integration of microcolumn.

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A micromachined cantilever for chemically sensitive scanning force microscope applications (화학적 성분 분석능력을 가진 원자 현미경의 제작)

  • Lee, Dong-Weon
    • Journal of Sensor Science and Technology
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    • v.14 no.1
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    • pp.1-6
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    • 2005
  • This paper describes a novel concept of a chemically sensitive scanning force microscope (CS-SFM). It consists of the conventional SFM and the time-of-flight mass spectrometer (TOF-MS). A switchable cantilever (SC) fabricated by the micromachining technology combines each advantage of two completely different systems, SFM and TOF-MS. The CS-SFM offers to produce both images of topography and chemical information simultaneously. First we employed a rotatable tip holder based on 4 piezotube actuators for demonstration of the possibility of the CS-SFM concept. Second the CS-SFM concept is optimized with the micromachining technology. The micromachined SC with an integrated bimorph actuator and a piezoresistive strain sensor provides a reasonable switching speed of ${\sim}10$ ms which is very attractive for the CS-SFM application. The SC is currently being integrated in an ultra-high-vacuum system to perform various experiments.

High-impulse, Low-Power Microthruster using Liquid Propellant with High-Viscosity Fluid Plug (저온 비등 팽창유체와 고점성 유체마개를 이용한 고출력 저전력형 마이크로 분사기)

  • Kim, Sang-Wook;Kang, Tae-Goo;Cho, Young-Ho
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.26 no.6
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    • pp.868-874
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    • 2002
  • A high-impulse, low-power, digital microthruster has been developed using low-boiling-temperature liquid propellant with high-viscosity fluid plug. The viscous fiction force of the fluid plug increases the blast pressure and the low-boiling-temperature liquid propellant is intended to reduce input power consumption. The three-layer microthruster has been fabricated by surface micromachining as well as bulk micromachining in the size of 7$\times$13$\times$1.5㎣. A digital output impulse bit of 6.4$\times$10$^{-8}$ Nsec has been obtained from the fabricated microthruster using perfluoro normal hexane (FC72) propellant and oil plug, resulting in about ten times increase of the impulse bit using one hundredth electrical input energy compared to the conventional multiple-shot microthruster.

Design, Fabrication and Performance Testing of a High-impulse, Low-Power Microthruster using Liquid Propellant with High Viscous Fluid Plug (저전력소비, 고출력, 연발형 마이크로 분사기의 설계, 제작 및 성능 시험)

  • Kim, Sang-Wook;Kang, Tae-Goo;Cho, Young-Ho
    • Proceedings of the KSME Conference
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    • 2001.06c
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    • pp.59-63
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    • 2001
  • A high-impulse, low-power, continuous-shot microthruster has been developed using low boiling temperature liquid-propellant with high viscous fluid-plug. The viscous friction force of the fluid-plug increases the blast pressure and the low boiling temperature liquid-propellant is intended to reduce input power consumption. The three-layer microthruster has been fabricated by surface micromachining as well as bulk micromachining in the size of $7{\times}13{\times}1.5mm^{3}$. A continuous output impulse bit of $6.4{\times}10^{-8}N{\cdot}sec$ has been obtained from the fabricated microthruster using perfluoro normal hexane (FC72) propellant and oil plug, resulting in about ten times increase of the impulse bit using one hundredth electrical input energy compared to the conventional continuous microthruster.

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Airbag Accelerometers Using Silicon Epitaxial Layers (실리콘 에피층을 이용한 자동차 에어백용 가속도계)

  • 고종수;김규현;이창렬;조영호;이귀로;곽병만
    • Transactions of the Korean Society of Automotive Engineers
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    • v.4 no.5
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    • pp.9-15
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    • 1996
  • A silicon microaccelerometer is designed and fabricated using silicon epitaxial layers for automotive electronic airbag applications. A cantilever structure is chosen for high sensitivity and piezoresistive detection method is adopted for circuit simplicity and low cost. An optimum design is used to find optimum microstructure sizes for maximum sensitivity subject to performance requirements and design constraints on natural frequency, damping ratio, maximum allowable stress and microfabrication limitations. The microaccelerometer is fabricated by micromachining processing steps, composed of material-selective and orientation-dependent chemical etching techniques. Fabricated prototype shows a sensitivity of 88.6$\mu\textrm{V}$/g within a resonant frequency of 1.75KHz. Estimated performance of the microaccelerometer is compared with measured one. Discrepancy between the theoretical values and the experimental values is discussed together with possible sources of the errors.

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Design and fabrication of micro force sensor using MEMS fabrication technology (MEMS 제작기술을 이용한 미세 힘센서 설계 및 제작)

  • 김종호;조운기;박연규;강대임
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 2002.05a
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    • pp.497-502
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    • 2002
  • This paper describes a design methodology of a tri-axial silicon-based farce sensor with square membrane by using micromachining technology (MEMS). The sensor has a maximum farce range of 5 N and a minimum force range of 0.1N in the three-axis directions. A simple beam theory was adopted to design the shape of the micro-force sensor. Also the optimal positions of piezoresistors were determined by the strain distribution obtained from the commercial finite element analysis program, ANSYS. The Wheatstone bridge circuits were designed to consider the sensitivity of the force sensor and its temperature compensation. Finally the process for microfabrication was designed using micromachining technology.

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Laser Microfabrication of Micro Actuator (레이저 미세 가공기술을 이용한 마이크로 엑츄에이터의 개발)

  • 김광열;고상철;박현기
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 2002.05a
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    • pp.932-937
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    • 2002
  • The polyimide nozzle and silicon restrictor inside a thermal micro actuator have been fabricated using state of the art laser micromachining methods. Numerical models of fluid dynamics inside the actuator chamber and nozzle are presented. The models include fluid flow from reservoir, bubble formation and growth, ejection through the nozzle, and dynamics of refill through restrictor. Since high tapered nozzle and restrictor are very important parameters for overall actuator performance design, a special setup for the beam delivery system has been developed. The effects of variations of nozzle thickness, diameter, taper angles, and restrictor shapes are simulated and some results are compared with the experimental results. It is fecund that the fluid ejection through the thinner and high tapered nozzle is more steady, fast, and robust and the tapered restrictor shows more satisfying refill than the zero taper one.

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Micromachining Thin Film Using Femtosecond Laser Photo Patterning Of Organic Self-Assembled Monolayers. (유기 자기조립 단분자막의 레이저 포토 패터닝을 이용한 박막 미세 형상 가공 기술)

  • Choi Moojin;Chang Wonseok;Kim Jaegu;Cho Sunghak;Whang Kyunghyun
    • Journal of the Korean Society for Precision Engineering
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    • v.21 no.12
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    • pp.160-166
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    • 2004
  • Self-Assembled Monolayers(SAMs) by alkanethiol adsorption to thin metal film are widely being investigated fer applications as coating layer for anti-stiction or friction reduction and in fabrication of micro structure of molecule and bio molecule. Recently, there have been many researches on micro patterning using the advantages of very thin thickness and etching resistance of Self-Assembled Monolayers in selective etching of thin metal film. In this report, we present the several machining method to form the nanoscale structure by Mask-Less laser patterning using alknanethiolate Self-Assembled Monolayers such as thin metal film etching and heterogeneous SAMs structure formation.

Glass Drilling using Laser-induced Backside Wet Etching with Ultrasonic Vibration (초음파 진동과 레이저 후면 에칭을 통한 유리 구멍 가공)

  • Kim, Hye Mi;Park, Min Soo
    • Journal of the Korean Society for Precision Engineering
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    • v.31 no.1
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    • pp.75-81
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    • 2014
  • Laser beam machining has been known as efficient for glass micromachining. It is usually used the ultra-short pulsed laser which is time-consuming and uneconomic process. In order to use economic and powerful long pulsed laser, indirect processing called laser-induced backside wet etching (LIBWE) is good alternative method. In this paper, micromachining of glass using Nd:YAG laser with nanosecond pulsed beam has been attempted. In order to improve shape accuracy, combined processing with magnetic stirrer has been widely used. Magnetic stirrer acts to circulate the solution and remove the bubble but it is not suitable for deep hole machining. To get better effect, ultrasonic vibration was applied for improving shape accuracy.

Fabrication of Carbon Nanotube Field Emitters

  • Yoon, Hyeun-Joong;Jeong, Dae-Jung;Jun, Do-Han;Yang, Sang-Sik
    • Journal of Electrical Engineering and Technology
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    • v.3 no.1
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    • pp.121-124
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    • 2008
  • This paper presents the fabrication and field emission of carbon nanotube field emitters for a micro mass spectrometer. The carbon nanotube is an adequate material as a field emitter since it has good characteristics. We have successfully fabricated a diode field emitter and a triode field emitter. Each field emitter has been constructed using several micromachining processes and a thermal CVD process. In the case of the diode field emitter, to increase the electric field, the carbon nanotubes are selectively grown on the patterned nickel catalyst layer. The electron current of the diode field emitter is 73.2 ${\mu}A$ when the anode voltage is 1100V. That of the triode field emitter is 3.4 pA when the anode voltage is 1000V.