Go to the main menu
Skip to content
Go to bottom
REFERENCE LINKING PLATFORM OF KOREA S&T JOURNALS
> Journal Vol & Issue
Journal of the Korean Vacuum Society
Journal Basic Information
Journal DOI :
The Korean Vacuum Society
Editor in Chief :
Volume & Issues
Volume 14, Issue 4 - Dec 2005
Volume 14, Issue 3 - Sep 2005
Volume 14, Issue 2 - Jun 2005
Volume 14, Issue 1 - Mar 2005
Selecting the target year
Study on the measurement of activation temperature of Non-Evaporable Getter
Lee D. J. ; Kim K. B. ; In S. R. ; Lim J. Y, ; Kim W. B. ;
Journal of the Korean Vacuum Society, volume 14, issue 1, 2005, Pages 1~6
Getters are invariably covered with thin layers of oxides even in air. For the getter to function properly it is necessary to activate them by heating in vacuum during which the oxide layer is removed exposing clean surface. The so-called activation temperature is an important parameter along with gas sorption capacity since it determines the maximum temperature of a device in which a getter can be installed. Nevertheless, no standard method to measure activation temperature has been documented yet. In this study, a relatively simple method to measure the activation temperature based on the ultimate pressure measurement was suggested. The activation temperature of TiZrV alloy measured by the method was between 100℃～200℃.
Investigation of new in the Oil-Hydraulic Pump Consisting of Swing Twin-Cylinder
Sim Woo Gun ; Kim Gi Son ;
Journal of the Korean Vacuum Society, volume 14, issue 1, 2005, Pages 7~16
Oil-Hydraulic pump consisting of swing twin-cylinder becomes to be used as a next generation of low vacuum pump. However, there is no enough flow-analysis for design improvement. It is essential to develope a numerical method for flow-analysis before manufacturing, in economic sense. Using a commercial code (Fluent), developed for flow-analysis, useful informations for design of pump were provided. Two-dimensional analysis has been performed to investigate the flow parameters such as pressure and velocity distributions between the swing twin-cylinder and the fixed cylinder. This numerical method will be used to design a better performance of pump consisting of swing twin-cylinder.
Trace impurity analysis of Cu films using GDMS: concentration change of impurities by applying negative substrate bias voltage
Lim Jae-Won ; Isshiki Minoru ;
Journal of the Korean Vacuum Society, volume 14, issue 1, 2005, Pages 17~23
Glow discharge mass spectrometry(GDMS) was used to determine the impurity concentrations of the deposited Cu films and the 6N Cu target. Cu films were deposited on Si (100) substrates at zero substrate bias voltage and a substrate bias voltage of -50 V using a non-mass separated ion beam deposition method. Since do GDMS has a little difficulty to apply to thin films because of the accompanying non-conducting substrate, we have used an aluminum foil to cover the edge of the Cu film in order to make an electrical contact of the Cu film deposited on the non-conducting substrate. As a result, the Cu film deposited at the substrate bias voltage of -50 V showed lower impurity contents than the Cu film deposited without the substrate bias voltage although both the Cu films were contaminated during the deposition. It was found that the concentration change of each impurity in the Cu films by applying the negative substrate bias voltage is related to the difference in their ionization potentials. The purification effect by applying the negative substrate bias voltage might result from the following reasons: 1) Penning ionization and an ionization mechanism proposed in the present study, 2) difference in the kinetic energy of accelerated Cu+ ions toward the substrate with/without the negative substrate bias voltage.
Crystallization characteristics of the amorphous Si thin films in the AMFC system
Kang Ku Hyun ; Lee Seung Jae ; Kim Sun Ho ; Lee Sue Kyeong ; Nam Seung Eui ; Kim Hyoung June ;
Journal of the Korean Vacuum Society, volume 14, issue 1, 2005, Pages 24~28
A typical method for obtaining poly-Si films is the solid phase crystallization(SPC) of amorphous Si. Advantages of SPC are uniformity, process quality and low cost of production. However, high process temperature and long process time prevent the employment of SPC process on thermally susceptible glass substrate. In this parer, we propose a new method that applies an alternating magnetic field during crystallization annealing in an alternating magnetic field crystallization(AMFC) system for lowering process temperature and shorter process time of SPC. When we crystallized, in the case of SPC, annealing time is 24 hours at 570℃. But in the case of AMFC, annealing time is only 20 minutes at the same temperature.
Degradation of the SiGe hetero-junction bipolar transistor in SiGe BiCMOS process
Kim Sang-Hoon ; Lee Seung-Yun ; Park Chan-Woo ; Kang Jin-Young ;
Journal of the Korean Vacuum Society, volume 14, issue 1, 2005, Pages 29~34
The degradation of the SiGe hetero-junction bipolar transistor(HBT) properties in SiGe BiCMOS process was investigated in this paper. The SiGe HBT prepaired by SiGe BiCMOS process, unlike the conventional one, showed the degraded DC characteristics such as the decreased Early voltage, the decreased collector-emitter breakdown voltage, and the highly increased base leakage current. Also, the cutoff frequency(f/sub T/) and the maximum oscillation frequency(f/sub max/) representing the AC characteristics are reduced to below 50%. These deteriorations are originated from the change of the locations of emitter-base and collector-base junctions, which is induced by the variation of the doping profile of boron in the SiGe base due to the high-temperature source-drain annealing. In the result, the junctions pushed out of SiGe region caused the parastic barrier formation and the current gain decrease on the SiGe HBT device.
The effect of wafer deformation on UV-nanoimprint lithography using an EPS(elementwise patterned stamp)
Sim Young-suk ; Jeong Jun-ho ; Sohn Hyonkee ; Lee Eung-sug ; Fang Lingmei ; Lee Sang-chan ;
Journal of the Korean Vacuum Society, volume 14, issue 1, 2005, Pages 35~39
In the UV-NIL process using an elementwise patterned stamp (EPS), which includes channels formed to separate each element with patterns, low-viscosity resin droplets with a nano-liter volume are dispensed on all elements of the EPS. Following pressing of the EPS, the EPS is illuminated with UV-light to cure the resin; and then the EPS is separated from several thin patterned elements on a wafer. Experiments on UV-NIL were performed on an EVG620-NIL. 50 - 100nm features of the EPS with 3m channels were successfully transferred to 4 in. wafers. Especially, the wafer deformation during imprint was analyzed using the finite element method (FEM) in order to study the effect of the wafer deformation on the UV-NIL using EPS.
Molecular Shuttle Memory System Based on Boron-Nitride Nanopeapod
Byun Ki Ryang ; Kang Jeong Won ; Choi Won Young ; Hwang Ho Jung ;
Journal of the Korean Vacuum Society, volume 14, issue 1, 2005, Pages 40~48
Bucky shuttle memory systems were investigated by the classical molecular dynamics(MD) simulations. Energetics and operating response of the shuttle-memory-elements u?ere examined by MD simulations of the C/sub 60/ shuttle in the nanomemory systems under various external force fields. Single-nanopeapod type was consisting of three fullerenes encapsulated in (10, 10) boron-nitride nanotube and filled Cu electrode. Studied systems could be applied to nonvolatile memory. MD simulation results showed that the stable bit flops could be achieved from the external force fields of 0.1 eV/Å for single-nanopeapod type.
Discharge Characteristics of the Cold Cathode and External Electrode Fluorescent Lamps
Cho Guangsup ; Lee Dae H. ; Lee Joo Y. ; Song Hyuck S. ; Gill Doh H. ; Koo Je H. ; Choi Eun H. ; Kim Sang B. ; Kim Bong S. ; Kang June G. ; Cho Mee R. ; Hwang Myung G. ; Kim Young Y. ;
Journal of the Korean Vacuum Society, volume 14, issue 1, 2005, Pages 49~57
The characteristics of current and voltage in a basic discharge experiment are investigated for a cold cathode fluorescent lamp with ballast capacitors attached at both ends of lamp and for a capacitive coupled external electrode fluorescent lamp. In the current-voltage characteristics for a cold cathode fluorescent lamp except ballast capacitors, it is shown that the typical glow discharge with the cathode fall follows after the dark current and Townsend firing discharge. However, in the characteristics for a cold cathode fluorescent lamp including ballast capacitors, the current increases as the voltage increases in the glow discharge region without representing a cathode fall since the most voltage is loaded at two capacitors. The characteristics for the external electrode fluorescent lamp shows the same as that of the cold cathode fluorescent lamp in the respect of glow discharge characters, and the external electrode itself roles the ballast capacitor.