AVS2001 Session SS3-MoP: Clusters and Aerosols Poster Session
Monday, October 29, 2001 5:30 PM in Room 134/135
Monday Afternoon
Time Period MoP Sessions | Topic SS Sessions | Time Periods | Topics | AVS2001 Schedule
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SS3-MoP-3 A Study on the High Rate Deposition of MgO Films Synthesized by Pulsed DC Magnetron Sputtering Process
Y.M. Chung (Sungkyunkwan University, South Korea) Magnesium Oxide (MgO) with a NaCl structure is known to exhibit high secondary electron emission, excellent high temperature chemical stability, high thermal conductance and electrical insulating properties. MgO films are very useful as a buffer layer for the deposition of high Tc superconducting and perovskite-type ferroelectric films, and as a protective layer for AC-plasma display panels to improve discharge characteristics and panel lifetime. For these purposes, the deposition and characteristics of the MgO films have been intensively studied by means of E-beam evaporation, Molecular Beam Epitaxy (MBE) and Metalorganic Chemical Vapor Deposition (MOCVD). However, there have been some limitations such as low deposition rate, micro-cracks during deposition process, and high erosion rate caused by ion bombardment in the glow discharge of AC-PDP. To improve these drawbacks MgO films were deposited on the dielectric substrates by pulsed DC magnetron sputtering with Mg and MgO targets. We have investigated the plasma states with various pulsed DC conditions, partial oxygen pressure and the deposition temperatures by Langmuir probe and Optical Emission Spectroscopy (OES). In order to confirm the relationships between plasma states and film properties deposition rate, microstructure, surface morphology, and composition were analyzed by α-step profilometer, XRD, TEM, AFM, and XPS. |
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SS3-MoP-4 The Surface Modification of PZT by Ion Bombardment
J.M. Choi (Samsung Advanced Institute of Technology, Korea); H.I. Lee (Korea Research Institute of Standards and Science (KRISS)); J.C. Lee (Samsung Advanced Institute of Technology, Korea); D.W. Moon (Korea Research Institute of Standards and Science (KRISS)) The surface of PZT (Pb1.0Zr0.4Ti0.6O3.0) film is modified by ion bombardment or reactive ion etching (RIE) process.1,2,3 In this work, Auger electron spectroscopy (AES),X-ray photoelectron spectroscopy (XPS), medium energy ion scattering spectroscopy (MEIS) and transmission electron microscope (TEM) were adapted to quantitatively analyze the modified surface layer. The AES and XPS depth profiles always show a rapid decrease of Pb intensity in the initial stage of sputter depth profiling, which has been known as the results of surface segregation of Pb3. But MEIS and TEM clearly showed that it is due to the formation of Pb depleted layer due to Pb preferential sputtering. The reduction of Pb concentration in the modified surface layer was about 30% and the thickness of Pb depleted layer was about 13nm by MEIS, in agreement with a 13.2nm thick amorphic layer observed by TEM. XPS spectra showed that Pb 4f shifted to the metallic phase, whereas Zr 3d and Ti 2p shifted to the ZrO2 and TiO2 phase. Preliminary results on recovery of the Pb depletion by electron beam bombardment and thermal treatment will be reported. |
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SS3-MoP-5 Formation of Boron-carbon Binary Clusters by Reactive Molecular Ion Irradiation
H. Yamamoto, T. Saito, H. Asaoka (Japan Atomic Energy Research Institute) We have observed boron-carbon clusters (BnCm) emitted from a boron surface under irradiation of reactive molecular ions, such as C6F5+, at 2-8 keV, 1µmA/cm2. In our previous work, enhanced silicon (Sin+, n≤8) and carbon (Cn-, n≤12) cluster formation have been observed emitted from an Si(100) and graphite surface under irradiation of molecular SF5+ ions at 4 keV, 1µmA/cm2.1 In both clusters, the intensities of n=4 and 6 are relatively higher than those of the neighboring clusters. Silicon-carbon binary cluster was also observed by the irradiation of C6F5+ to Si(100) surface. However, SinCm binary clusters which contain more than two carbon atoms (m≥2) were scarcely observed.2 In the present study, BnCm binary clusters are formed through the reaction between the irradiated ion and target atoms. The observed clusters show a yield alternation between odd and even number of constituent atoms. The intensities of n+m=4 and 6 clusters are relatively higher than those of the neighboring clusters even at the present condition. The intensities of the BnCm clusters (m≥2) are also higher than those of SinCm (m≥2). It can be considered that the BnCm (m≥2) clusters are more stable than SinCm (m≥2) since the diameter of the boron and carbon atoms are not so different.. |
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SS3-MoP-8 Controlled Surface Charging in XPS as a Tool for Fine Structural Analysis
H. Cohen (The Weizmann Institute of Science, Israel) Surface charging in XPS can seriously smear chemical information. On the other hand, it frequently provides valuable structural and electrical information. Can the controlled surface charging (CSC)1 become a quantitative tool? What are the limits of this probe in terms of spatial resolution, reliability and applicability? These questions and others are discussed in view of supporting experimental results. Enhanced capabilities for structural analysis, down to nm resolution, are demonstrated. |