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 1, Issue 3 - Oct 1992
Volume 1, Issue 2 - Jun 1992
Volume 1, Issue 1 - Feb 1992
Selecting the target year
Effect of Chemical Cleaning on Vacuum Properties of a Stainless Steel Surface
Journal of the Korean Vacuum Society, volume 1, issue 1, 1992, Pages 1~10
Three chemical precleaning methods-degreasing, electropolishing and acidic etching-suitable for stainless steel vacuum chamber have been studied and compared. The techniques used in evaluating and comparing the three treatments include Auger analysis and the measurement of the outgassing rate. The obtained outgassing rates (N2 equivalent) are 1.1
10-10torr l/s cm2 and 3.9
10-11torr l/s cm2 for degreasing electropolishing, and etching method, respectively, after 48 hours from the initial pumpdown at room temperature. A simple model is introduced to analyze the pumpdown curve. Some surface parameters, such as surface coverage, mean residence time, and desorption energy, are calculated from corresponding equations derived from this model.
The Conductances of Porous Plugs Made of Tungsten Wires
Journal of the Korean Vacuum Society, volume 1, issue 1, 1992, Pages 11~15
The conductances of the porous plugs, which are made by inserting tungsten wires into small holes, are calculated and compared with values measured by experiment. For the porous plug with no wire, the ratio K of Cexp and Ctheo is in the range 0.91-1.00, and in the range 0.77-0.78 and 0.85-0.88 for plugs with three and four wires, respectively. The variations in conductances as a function of exposure time to the air were measured and in no case have variations of more than +0.4 percent been observed.
Effect of Gas Beaming in the Calculation of Tube Conductance
Journal of the Korean Vacuum Society, volume 1, issue 1, 1992, Pages 16~23
Conductance calculation is essential in designing a vacuum system. Since mathematical solution is nearly impossible except for a few simple cases, it has been so usual to calculate the conductance for a series connection of components using an approximate formula by Oatley. However, Oatley's formula has a fundamental flaw of totally neglecting the effect of gas beaming. In this study, a new technique is suggested for calculating the conductance with the same accuracy as the Monte Carlo method but with much less computing time, and applied to a system of tube connections in series. The effects of gas beaming in the calculation of conductance is analyzed quantitatively by comparing the conductance calculated by this method with those from Oatley's formula.
Vacuum Chamber Design for the PLS Storage Ring
Journal of the Korean Vacuum Society, volume 1, issue 1, 1992, Pages 24~27
The Pohang Accelerator Lab is constructing a 2 GeV synchrotron radiation source. In order to achieve a beam lifetime of 5 hours or more, the average pressure in the vacuum chamber will be kept in the nano Torr range. Each chamber consists of a top and a bottom piece, which are machined separately and welded together. The chamber material is A1 5083-H321. The pumping system has nine sets of lumped NEGs in tandem with ion pumps installed beneath photon stops, and six ion pumps per superperiod. A prototype chamber will be machined by February 1992. After various tests with the prototype chamber, the vacuum chamber design will be refined.
Achievement of a
Torr Ultrahigh Vacuum System
Journal of the Korean Vacuum Society, volume 1, issue 1, 1992, Pages 28~31
Construction of an Electron Cyclotron Resonance Plasma Apparatus
Journal of the Korean Vacuum Society, volume 1, issue 1, 1992, Pages 32~36
An ECR plasma apparatus is designed and constructed. The gradient of magnetic field in microwave cavity was adjusted to provide an ECR plasma stream by electro magnetic lenz system. Employing a yoke arround the electro magnets, the magnetic field intensity was increased by 50% with the same electric current. Characteristics of the ECR plasma discharged in the apparatus were investigated by Langmuir probe method. The variations of electron temperature and electron density along chamber axis were analysed.
A Study on the Characteristics of Poly-Si Etching Process Parameter Using ECR Plasma
Journal of the Korean Vacuum Society, volume 1, issue 1, 1992, Pages 37~42
Abstract-The ECR(E1ectron Cyclotron Resonance) plasma etcher was developed for process of manufacturing 16M164' DRAM and applied to poly-Si etching process. The etching rate and selectivity of poly-Si were investigated by changing the process factor of pressure gas and microwave power. The increasing power of microwave will have the trend of increasing the etching rate and selectivity of Oxide, and have suitable value process pressure at 6 mTorr. The increasing value of process gas SFdSF6+ Clz will cause the decrease of etching rate and selectivity, this is because the best process factor is not found.
Construction of RHEED Apparatus and Study on K, Cs/Si)(111) System
Journal of the Korean Vacuum Society, volume 1, issue 1, 1992, Pages 43~49
RHEED apparatus which is one of the systems of surface structure analysis has been constructed.Electron beam is focused by means of magnetic lens, and the beam divergence is about 1 X rad. The Accelerationvoltage of this RHEED apparatus is continuously variable from 0 to 20 kV. K and Cs-adsorbed structureson Si(111)7X7 surface at room and high temperatures(200X700"C) have been investigated by RHEED. It isobserved that the K and Cs-adsorbed Si(ll1)surface structures at saturation coverage are Si(111)7X7-K andSi(1ll)lX 1-Cs at room temperature, respectively. When the specimen temperature was elevated during evaporation,the 3 x 1 structure appears in the range of temperature between 300"cnd 550"c, and the 1x1 structureappears above 550"cn WSi(ll1)system. Also, in Cs/Si(lll) system the f i ~ f l s t r u c t u r e appears at 300"C,and the flx\/5+3~ 1 structure appears between 350
C and 400
C.1 . 4 # %@%! 014 %'||'&'||' 97%}$C. 1 . 4 # %@%! 014 %& 97%
The Initial Stages of the Oxidation of the CdTe surfaces
Journal of the Korean Vacuum Society, volume 1, issue 1, 1992, Pages 50~59
By means of X-ray photoelectron spectroscopy(XPS), the initial stages of the oxidation of the cleaved CdTe (110) surface and the sputtered CdTe surface with oxygen exposure are invetigated. From the analyses of the spectra of Te 3dsn, Cd 3d5/2, 0 ls and Cd MNN Auger lines, it is shown that two oxygen atoms bond to one Te atom at the initial stages.
The Subband Energy and The Envelope Wave Function of The Semiconductor Superlattice
Journal of the Korean Vacuum Society, volume 1, issue 1, 1992, Pages 60~66
The electronic subband structure and the envelope wave function for three types of superlattices are calculated with a new method. Comparison of the results of this method with those of other methods has proved the validity of this method. In particullas, the results of saw-toothed superlattices show that the change of the effective mass with position must be considered. Therefore this method can be easily applied to arbitrily shaped superlattices and multiple quantum well structures.
Growth of Ti on Si(111)-)-
Surface and the Formation of Epitaxial C54
on Si(111) Substrate
Kun Ho Kim ; In Ho Kim ; Jeoung Ju Lee ; Dong Ju Seo ; Chi Kyu Choi ; Sung Rak Hong ; Soo Jeong Yang ; Hyung Ho Park ; Joong Hwan Lee ;
Journal of the Korean Vacuum Society, volume 1, issue 1, 1992, Pages 67~72
The growth of Ti on Si(ll1)-7x7 and the formation of epitaxial C54 TiSip were investigated by usingreflection high energy electron diffraction(RHEED) and high resolution transmission electron microscopy(HRTEM).Polycrystalline Ti layer is grown on the amorphous Ti-Si interlayer which is formed at the Ti/Si interface byTi deposition on Si(ll1)-7X 7 at room temperature (RT). HRTEM lattice image and transmission electron diffraction(TED) showed that epitaxial C54 TiSiz grown on Si substrate with 160 ML of Ti on Si(ll1)-7x7 surface at RT, followed by annealing at 750"Cor 10 min in UHV. Thin single crystal Si overlayer with [Ill] direction is grownon TiSiz surface when TiSi2/Si(lll) is annealed at -9002 in UHV, which was confirmed by Si(ll1)-7x7superstructure7x7 superstructure
Thickness Measurement of Overlayer Deposited on Single Crystal
Journal of the Korean Vacuum Society, volume 1, issue 1, 1992, Pages 73~77
It is not easy to determine the coverage of deposited overlayers on a single crystal. There are several techniques determining the overlayer thickness. We propose, in this study, a new simple method by using Auger spectra only without any sophisticated thickness monitor. An example of iron overlayers on copper single crystals is also showed.
Work Function Change of W(123) Plane Due to Hydrogen and Deuterium Adsorption at 78K
Journal of the Korean Vacuum Society, volume 1, issue 1, 1992, Pages 78~82
The changes in work function due to hydrogen and deuterium adsorption on W(123) plane are measured by means of Field Emission Method. In the case of hydrogen or deuterium adsorption, work function of W(123) plane at 78 K increase and after a maxium value, it decrease and saturated as increasing coverage. After annealing the tungsten emission tip at 200 K, the coverage corresponding to maximum change in work function was shifted toward low coverage and the effect of work function by terraces or steps of which orientation is [ O l l ] was observed.
Surface Reconstruction on Hydrogen Covered W(011)
Journal of the Korean Vacuum Society, volume 1, issue 1, 1992, Pages 83~87
Rencently, angle-resolved ultraviolet photoemission measurements of the Fermi surface contours for Mo(Ol1) and W(Ol1) are reported. The electron contour of W(Ol1) is expanded upon hydrogen adsorption, which implies that the surface states consisting of electron pockets are shifted to higher binding energy. This phenomena can be explained by the band flattening. We explained here the reconstruction of W(Ol1) surface induced by adsorption of hydrogen in terms of band flattening of surface states with a combination of S. E. Trullinger long range dipole-dipole interaction force and Kohn anomaly.
Exponent Study of the p(
) Phase on an O/W(110) Surface
Journal of the Korean Vacuum Society, volume 1, issue 1, 1992, Pages 88~95
Abstract-Using a high resolution low energy electron diffraction(HRLEED), we report an exponent study of 2d continuous phase transition from an ordered ~ ( 2 x 1 )ox ygen overlayer on a W(110) surface. Temperature dependence of a (% 0) superlattice diffraction spot, characteristic of the p(2X 1) structure, shows power-law like divergence of the susceptibility and the fluctuation correlation length at T,=708.765 K. By fitting the intensities as well as the line-shapes, we obtained exponents P=0.19* 0.05, y=1.48+ 0.34, v= 1.23i 0.27 and q=0.38+ 0.12. The non-universal character of the exponents are understood in terms of a 2d XY model with cubic anisotropy as suggested previously.
Oxygen Coverage Measurment on Tungsten Surface by Neclear Microanalysis
Journal of the Korean Vacuum Society, volume 1, issue 1, 1992, Pages 96~99
The microanalysics by the direct observation of 180 (P, a)'" nuclear reactions on tungsten (110) surfaceare investigated using a 2MeV Van de Graaff accelerator. This method allows the determination of very smallquantities of nuclei near the surface of samples. The yields increase with oxygen exposure. The oxygen coverage, 0, is 0.5 at 5 Langmuir and 1.0 at 15 Langmuir.5 Langmuir.
Characterization of Surface Oxides in Gold Thin Films with V- and Ti- underlays by AES and XPS
Kim, Jin -Young ;
Journal of the Korean Vacuum Society, volume 1, issue 1, 1992, Pages 100~105
Auger electron spectroscopy (AES) and X-ray photoelectron spectroscopy (XPS) analyses have been performed on double-structured Au/V and Au/Ti thin films after heat treatment at 500
C in air. V- and Tiunderlays sandwiched between gold thin films and SiOz substrates form oxides on the free surface of gold films during the heat treatment. The chemical compositions of the oxides were identified as V205 and TiOz in Au/V and Au/Ti thin films, respectively.
Quantitative Surface Analysis of Co-Ni and Au-Cu alloys by XPS and SIMS
Journal of the Korean Vacuum Society, volume 1, issue 1, 1992, Pages 106~114
Abstract-Quantitative surface analysis of Co-Ni and Au-Cu alloys by XPS and SIMS was studied. For Co-Ni alloy, quantitative XPS analysis could be done within 1-2% relative error with pure element standards without any correction. For Au-Cu, quantitative XPS analysis was not possible without any correction. But it could be done with standard alloys of various composition within 1-2% relative error. Without standard alloys, Au-Cu alloys could be analyzed by XPS within 10% relative error with pure element standards. For SIMS analysis of Co-Ni alloys, the relative secondary ion yields of Co+/Nit has linear relation with ratio of each composition so that quantitative SIMS analysis was possible for Co-Ni alloys. Preliminary results of XPS round robin test of VAMAS-SCA Japan Project are given.
Research of Matrix Effect Reduction of
Journal of the Korean Vacuum Society, volume 1, issue 1, 1992, Pages 115~120
SIMS is an indispensable surface analysis instrument in trace element depth profiling because of high detection sensitivity and excellent depth resolution, however, it requires a standard sample to do quantitative analysis due to matrix effect depending on the species of impurities and sample matricies and on the sputtering rates. Among the SNMS technology developed to supply the deficiency, we researched into CsX+ SNMS which improved the result quantitatively without any extra epuipments. So basic SNMS functions were confirmed through matrix element composition rate analysis using Siq layer etc., and adaptability to trace element concentration alaysis was tried. For that purpose we compared SIMS depth profile data for Boron which presented strong matrix effect on account of Fluorin existence after BF2 ion implantation on silicon substrate with SNMS data. Also detection limit and dynamic range were investigated. After these experements we concluded that CsX+ SNMS reduced matrix effect and we could apply it to profile impurity elements.
The Detection of Molecular Ion
(X=Al, Ga, As) for Quantitative SIMS Analysis
Journal of the Korean Vacuum Society, volume 1, issue 1, 1992, Pages 121~125
Secondary Ion Mass Spectrometry (SIMS) is widely known as highly sensitive a surface analysis technique. Efforts for quantification have been hindered, however, by the presence of matrix effects. Here we describe a new technique for the quantitative analysis of AlxGa1-xAs. Instead of Al+, Ga+, As+ ions, CsX+ ions (X=Al, Ga, As) have been detected. Intensity of these molecular ions appears to be much less affected by matrix effects. We have successfully accomplished the compositional analysis with standard deviation better than 2 percent.
Crystal Growth Sensor Development of II-VI Compound Semiconductor : CdS
D.I. Yang ; Y.J. Shin ; S.Y. Lim ; Y.D. Choi ;
Journal of the Korean Vacuum Society, volume 1, issue 1, 1992, Pages 126~133
This study deals with the crystal growth and the optical characteristics of CdS thin films activatedby silver. CdS:Ag thin films were deposited by using an electron beam evaporation(EBE) technique in vacuumof 1.5X 10-'torr, voltage of 4 kV, current of 2.5 mA and substrate temperature of 250
C CdS:Ag photoconductivefilms prepared by EBE method show high photoconductivity after annealing at about 550"c for 0.5 h in air andAr gas.The grain size of CdS:Ag thin films annealed in Ar atmosphere (1 atm) was grown over 1 ym and the thicknessof the films is 4-5 pm. The analysis of X-ray diffraction patterns shows that the crystal structures are hexagonal.The diffraction line by (00.2) plane can only be observed, indicating that c-axis of hexagonal grows preferentiallyperpendicular to the substrate. The profiles of photoluminescence spectra of CdS:Ag films show Gaussian typecurves at room temperature, the maximum peak spectral sensitivity of CdS:Ag is located at the wavelength of520 nm.We annealed CdS:Ag thin films in air and Ar vapor in order to make the CdS photoconductors having theintensive photocurrent, the broad distribution of the photocurrent spectrum and the large value of the ratioof the photocurrent (pc) to the dark current(dc). We found that CdS:Ag thin films annealed in air atmospherewas the best one.air atmosphere was the best one.
Growth and Characterization of the Multi Quantum Wells by MBE(The Growth and Electrical Properties of Resonant Tunneling Structures)
Journal of the Korean Vacuum Society, volume 1, issue 1, 1992, Pages 134~138
The GaAs/AlAs double barrier structures was grown by MBE(Mo1ecular Beam Epitaxy). Mesa diode was fabricated and I-V characteristics of the diode were measured by semiconductor parameter analyser at room temperature. TEM pictures show the double barrier structure with abrupt interface. PVCR(Peak to Valley Current Ratio) proves to be independent of barrier thickness. These results show that increase in barrier thickness leads to larger valley current by non-resonant tunneling.
Chemical and Crystalline Properties of Polyimide Film Deposited by Ionized Cluster Beam
K.W. Kim ; S.C. Choi ; S.S. Kim ; S.J. Cho ; S.Y. Hong ; K.H. Jeong ; J.N. Whang ;
Journal of the Korean Vacuum Society, volume 1, issue 1, 1992, Pages 139~144
Abstract-Polyimide (PI) thin films were deposited by the ionized cluster beam deposition (ICBD) technique. Imidization and crystallization of PI films were investigated using transmission electron microscopy (TEM) and Fourier transform infrared spectroscopy (FT-IR). PI films deposited under optimum conditions showed a maximum imidization and good crystal structure, which are superior to those of the films fabricated by other techniques.
The Characteristics of Residual Films on Silicon Surface
Reactive Ion Etching
Journal of the Korean Vacuum Society, volume 1, issue 1, 1992, Pages 145~152
Si surfaces exposed to CHF3/C2F6 gas plasmas ih reactive ion etching (RIE) have been characterized by X-ray photoelectron spectroscopy (XPS). CHF3/C2F6 gas plasma exposure of Si surface leads to the deposition of residual film containing carbon and fluorine. The narrow scan spectra of C 1s show various bonding states of carbon as C-Si, C-F/H, C-CFx(x
3), C-F, C-F2, and C-F3. The chemical bonding states of fluorine are described with F-Si, F-C and F-O. And the oxygen and silicon are also detected. The effects of parameters for reactive ion etching as CHF3/C2F6 gas ratio, RF power, and pressure are investigated.
PECVD of Blanket
on Oxide Patterned Wafers
Lee, Jaegab ;
Journal of the Korean Vacuum Society, volume 1, issue 1, 1992, Pages 153~161
A plasma has been used in a high vaccum, cold wall reactor for low temperature deposition of C54 TiSi2 and for in-situ surface cleaning prior to silicide deposition. SiH4 and TiCl4 were used as the silicon and titanium sources, respectively. The deposited films had low resistivities in the range of 15~25 uohm-cm. The investigation of the experimental variables' effects on the growth of silicide and its concomitant silicon consumption revealed that and were the dominant species for silicide formation and the primary factors in silicon consumption were gas composition ratio and temperature. Increasing silane flow rate from 6 to 9 sccm decreased silicon consumption from 1500 A/min to less than 30 A/min. Furthermore, decreasing the temperature from 650 to
achieved blanket silicide deposition with no silicon consumption. A kinetic model of silicon consumption is proposed to understand the fundamental mechanism responsible for the dependence of silicon consumption on SiH4 flow rate.
Annealing Effects on TiC and TiN Thin Films
Journal of the Korean Vacuum Society, volume 1, issue 1, 1992, Pages 162~167
Tic and TiN layers were deposited on the stainless steel substrate by the reactive RF sputtering. Ar was used for sputtering gas and CzHz and Nz were used for reaction gas. Deposition rate increased linearly to the applied RF power, and decreased as the partial pressure ratio of sputter gas to reactive gas increased. The thin layers were stoichiometric at the partial pressure ratio of 0.03 for Tic and at partial pressure ratio of 0.05 for TiN. The morphologies and structures of the thin layers were investigated by AES, SEM and TEM. In addition, N+ ion was implanted to Tic and the resulting influence on the film and annealing effects were also examined.
Study on the Improvement of
film for Ti-SALICIDE Process Using Ion Beam Mixing and Rapid Thermal Annealing
Journal of the Korean Vacuum Society, volume 1, issue 1, 1992, Pages 168~175
The surface and interface morphology as well as the sheet resistance, and uniformity of TiSiz film are significantly improved and the lateral titanium silicide growth over the oxide spacer is minimized by the use of ion beam mixing and rapid thermal annealing in nitrogen ambient. In addition, TiSiz film formations on TiISi and TiISiOz system were also studied.
Stress and Junction Leakage Current Characteristics of CVD-Tungsten
Journal of the Korean Vacuum Society, volume 1, issue 1, 1992, Pages 176~182
t-Stress and junction leakage current characteristics of CVD-tungsten have been investigated. Stressversus continuous annealing temperature plot. shows hysteresis curve where the stress level of the cooling curveis higher than that of the heating curve. It is found that the thermal and intrinsic stress of tungsten film depositedby SiH4 reduction is higher than that by Hz reduction.The tungsten film deposited by SiHl reduction is in the tensile stress state below 700"Cnd the stress ofthe film decreses with increasing annealing temperature. The stress state changes into compressive stress atabout 700"Cnd the compressive stress increases rapidly with increasing temperature.Leakage current of the n+/p diode increases rapidly especially in the range of 400-450
C with increasingdeposition temperature of the CVD-W by SiH4 reduction, which is due to the Si consumption by W encroachment.On the other hand leakage current of the n+/p diode slightly increases with increasing SiH4/WF6 ratio.h increasing SiH4/WF6 ratio.
Characterization of Thin
Journal of the Korean Vacuum Society, volume 1, issue 1, 1992, Pages 183~189
The characteristics of N/O(SiOz/SisN4) film on WSi2 are compared with storage node Poly-Si. Leakage current and breakdown voltage are improved and storage capacitance is decreased. The oxidation rate of WSiz is more rapid than polycrystalline silicon. Thus the thick bottom oxide on the WSiz causes to the decrease of capacitance. The out diffusion of dopant impurity in polycrystalline silicon through the silicide leads to the formation of a depletion region in the polycrystalline silicon and the decrease of depletion capacitance. That results in the decrease of the overall storage capacitance.
Characteristics of High Temperature Oxide Thin Film Using Dichlorosilane Gas
Journal of the Korean Vacuum Society, volume 1, issue 1, 1992, Pages 190~197
In this study we have investigated physical and electrical properties of high temperature oxide (HTO) thin film using dichlorosilane (DCS) gas. This film had low etch rate and excellent step coverage, and its characteristics of Si-O bond were similar to those of thermal oxide. I-V curves also showed similar electrical properties to those of thermally grown oxide (SiO2) while time dependent dielectric breakdown (TDDB) results revealed 1/4 value of thermal oxide. However, defect density was measured to be much lower value than that of thermal oxide.
Optimization of Spin-On-Glass Planarization Process Using Statistical Design of Experiments
Journal of the Korean Vacuum Society, volume 1, issue 1, 1992, Pages 198~205
Abstract-Planarieation technology, which is essential to VLSI, has been developed using non-etch back Spin- On-Glass (SOG). Process factors for 1.5 micron double metal technology are optimized by the statistical design of experiments. Optimum conditions are found to be a process with twice SOG coating, sufficiently long hot plate baking at 300t, and furnace curing for 40 minutes below 400
Behavior of Oxygen Precipitates during SIMOX SOI Fabrication and Their Influences to the Electrical Property
Bae, Young-Ho ; Chung, Woo-Jin ; Kim, Kwang-Il ; Kwon, Young-Kyu ; Kim, Bum-Man ; Cho, Chan-Sub ; Lee, Jong-Hyun ;
Journal of the Korean Vacuum Society, volume 1, issue 1, 1992, Pages 206~211
SIMOX SOI structures were formed by oxygen ion implantation with a dose of 2 1018 ions/cm2 at 180kev and post-implantation annealing at
for 6 hours in nitrogen ambient. The oxygen redistribution process during post-implantation annealing was examined by AES and TEM. The electrical property of the structure was investigated by SRP method. We could find oxygen precipitates in SOI layer was discussed. And the limiting factor to the decrease of the precipitates during post-implantation annealing was discussed also.
Polycrystalline Silicon Thin Film Transistor Fabrication Technology
Journal of the Korean Vacuum Society, volume 1, issue 1, 1992, Pages 212~222
To use polycrystalline Si Thin Film Transistor (poly-Si TFT) in high density SRAM instead of High Load Resistor (HLR), TFT is needed to show good electrical characteristics such as large carrier mobility, low leakage current, high driver current and low subthreshold swing. To satisfy these electrical characteristics, the trap state density must be reduced in the channel poly. Technological issues pertinent to the channel poly fabrication process are investigated and discussed. They are solid phase growth (SPG), Si-ion implantation, laser annealing and hydrogenation. The electrical properties of several CVD oxides used as the gate oxide of TFT are compared. The dependence of the electrical characteristics of TFT on source-drain ion-implantation dose, drain offset length and dopant lateral diffusion are also described.