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REFERENCE LINKING PLATFORM OF KOREA S&T JOURNALS
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Journal of the Korean Vacuum Society
Journal Basic Information
Journal DOI :
The Korean Vacuum Society
Editor in Chief :
Volume & Issues
Volume 11, Issue 4 - Dec 2002
Volume 11, Issue 3 - Sep 2002
Volume 11, Issue 2 - Jun 2002
Volume 11, Issue 1 - Apr 2002
Selecting the target year
Sealing Test of the Helicoflex Gasket
Journal of the Korean Vacuum Society, volume 11, issue 2, 2002, Pages 81~86
With a specific model for the Helicoflex type metal gasket expected to be used in large ports of the KSTAR vacuum vessel, a sealing curve was obtained by measuring the flange tightening properties such as the correlations of the tightening torque(or linear load), displacement to the leak rate. From the experiment results it was found that the leak rate of the Helicoflex seal in the room temperature was bellow
with a tightening torque of 2500kgf . cm using Ml8 bolts.
A Study on the contamination measurement of spacecraft components under High Vacuum Environment
Journal of the Korean Vacuum Society, volume 11, issue 2, 2002, Pages 87~96
Outgassing from such sources as paints, coatings, adhesives and other non-metallic surfaces can contaminate satellites, especially second surface mirror and optical lens, it cause satellite to fail in own missions. The vacuum bake-out test using high temperature(more than
)and high vacuum(less than
Pa) certify that the components of satellite work properly and can survive and operate in space environment like high vacuum. In the bake-out chamber installed at SITC of KARI, Rotary vacuum pump and Booster pump produce low vacuum of 5.0 Pa, and then two cryopumps produce high vacuum of below
Pa. Also 48 ceramic heaters were provided to simulate high temperature. During the vacuum bake-out test, we detected contaminants using RGA(Residual Gas Analyzer) and measure the outgassing rate of the contaminant using the TQCM(Thermoelectric Quartz Crystal Microbalance). Also, IR/UV Spectrometer and witness plate be used to certify that the components were suitable for the spacecraft. This paper includes the preparation and procedures of the bake-out test for SAR(Solar Array Regulator) and MLI(Multi Layer Insulator), which were the components of the spacecraft. Especially, we discussed the methods and results of the contamination measurement. In the bake-out for SAR, the contamination was measured continuously although it was on the decrease from TQCM results. And RCA established that it is a highly polymerized compound. In the MLI bake-out using RGA and witness plate, we didn't detect any contamination materials.
Growth and structural characterization of ZnO thin film on silicon substrate by MOCVD method
Journal of the Korean Vacuum Society, volume 11, issue 2, 2002, Pages 97~102
Highly-oriented ZnO thin films has been successfully deposited on Si(100) by metal organic chemical vapor deposition(MOCVD) at
We report on the structural properties of ZnO thin film at various temperatures and at various ratios of the he and
gas flow rates. The crystallinity of the thin films was improved and the surface smoothness decreased with the increase of the growth temperature. In x-ray diffraction analysis with respect to ZnO(0002) peak, the full width at half maximum (FWHM) of
was achieved at
Properties of MFSEET′s with various gate electrodes using
ferroelectric thin film
Journal of the Korean Vacuum Society, volume 11, issue 2, 2002, Pages 103~107
Metal/ferroelectric/semiconductor field effect transistors(MFSFET′s) with various gate electrodes, that are aluminum, platinum and poly-Si, using rapid thermal annealed
/Si(100) structures were fabricated and the properties of the FET′s have been discussed. The drain current of the "on" state of FET with Pt electrode was more than 3 orders of magnitude larger than the "off" state current at the same "read" gate voltage of 1.5 V, which means the memory operation of the MFSFET. A write voltage as low as about
4 V, which is applicable to low power integrated circuits, was used for polarization reversal. The retention properties of the FET using Al electrode were quite good up to about
s and using Pt electrode remained almost the same value of its initial value over 2 days at room temperature.
Study of the characteristics of Secondary Electron Emission from MgO Layer for Low-Energy Noble Ions
Journal of the Korean Vacuum Society, volume 11, issue 2, 2002, Pages 108~112
We investigated the secondary electron emission characteristics of MgO layer used as the protecting material in a.c. plasma display panel(a.c.-PDPs) using a pulsed ion beam technique, where the surface charging can be effectively suppressed during the measurement. The measurement of the secondary electron emission coefficients (
) on the surface of
was carried out and then, it was found that the yields were dependent on incident ion energies. In addition, it was clearly demonstrated that the sputtering on MgO surface leads to lower yields, which suggests that the surface plays a key role on the operating conditions, such as life time, fast response, and etc.
Effect of Gas now Modulation on Etch Depth Uniformity for Plasma Etching of 150 mm GaAs Wafers
Journal of the Korean Vacuum Society, volume 11, issue 2, 2002, Pages 113~118
We developed engineering methods to control gas flow in a plasma reactor in order to achieve good etch depth uniformity for large area GaAs etching. Finite difference numerical method was found quite useful for simulation of gas flow distribution in the reactor for dry etching of GaAs. The experimental results in
ICP plasmas confirmed that the simulated data fitted very well with real data. It is noticed that a focus ring could help improve both gas flow and etch uniformity for 150 mm diameter GaAs plasma etch processing. The simulation results showed that optimization of clamp configuration could decrease gas flow uniformity as low as
1.5% on an 100 mm(4 inch) GaAs wafer and
3% for a 150 m(6 inch) wafer with the fixed reactor and electrode, respectively. Comparison between simulated gas flow uniformity and real etch depth distribution data concluded that control of gas flow distribution in the chamber would be significantly important in order or achieve excellent dry etch uniformity of large area GaAs wafers.
Measurement of Optogalvanic Signal in Hollow Cathode Discharge Tube
Journal of the Korean Vacuum Society, volume 11, issue 2, 2002, Pages 119~126
The optogalvanic signals were measured using hollow cathode discharge tube with argon as buffer gas at change of discharge currents. A change of ionization rate due to electron collision causes an increase or decrease of the electric conductivity, This change in electric conductivity generates the optogalvanic signal. We conclude that optogalvanic signal has close relation with change of the lowest metastable atoms density at low current.
A Study on the Discharge Characteristics with New Penning Gas Mixture for AC plasma display panel
Journal of the Korean Vacuum Society, volume 11, issue 2, 2002, Pages 127~134
Recently, Plasma display panel(PDP) has been in the spotlight as one of the next generation flat-panel-display device. The luminance and luminous efficiency improvement is the hot issues for making a plasma display into a large flat panel device. In this paper, We suggest a new penning gas mixture, in order to find the optimum mixture gas in plasma display panel. The optimum gas composition has been found by the partial pressure of inert gases(such as Af and Kr added to matrix of He(70%)-Ne(27%)Xe(3%) and Ne(96%)-Xe(4%)). The influences of Ar or Kr addition to Ne(96%)-Xe(4%) and He(70%)-Ne(27%)-Xe(3%) mixture gases are experimentally investigated for AC Plasma Display Panel. When rare As(0.01%-0.03%) or Kr(0.01%-0.03%) is added Ne-Xe and He-Ne-Xe mixture gases, the luminance increases over 10%-20% and luminous efficiency increases over 10%-20% at 200 Torr. It is sure that luminance and efficiency are improved by Penning effect. Also, This influence of Penning effect is shown by increased wall charge(10%-25%). In addition to the result, firing voltage and minimum sustain voltage was approximately decreased by 2V-3V.