• Proceedings of the Korean Vacuum Society Conference
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• 2012.02a
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• pp.371-372
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• 2012

We have studied lead-based gapless semiconductors, $PbPdO_2$, which is very sensitive to external parameters such as temperature, pressure, electric field, etc[1]. We have fabricated pure $PbPdO_2$, Co- and Mn-doped $PbPdO_2$ thin films using the pulsed laser deposition. Because of the volatile element of Pb, it is very difficult to grow the films. Note that in case of $MgB_2$, Mg is also volatile element. So in order to enhance the quality of $MgB_2$, some experiments are carried out in annealing with Mg-rich atmosphere [2]. This annealing process with volatile element plays an important role in making smooth surface. Thus, we applied such process to our studies of $PbPdO_2$ thin films. As a result, we found the optimal condition of ex-situ annealing temperature ${\sim}650^{\circ}C$ and time ~12 hrs. The ex-situ annealing brought the extreme change of surface morphology of thin films. After ex-situ annealing with PbO-rich atmosphere, the grain size of thin film was almost 100 times enlarged for all the thin films and also the PbO impurity phase was smeared out. And from X-ray diffraction measurements, we determined highly crystallized phases after annealing. So, we measured electrical and magnetic properties. Because of reduced grain boundary, the resistivity of ex-situ annealed samples changed smaller than no ex-situ sample. And the carrier densities of thin films were decreased with ex-situ annealing time. In this case, oxygen vacancies were removed by ex-situ annealing. Furthermore, we will discuss the transport and magnetic properties in pure $PbPdO_2$, Co- and Mn-doped $PbPdO_2$ thin films in detail.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2005.11a
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• pp.61-62
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• 2005

The present article deals with in situ post annealing of ZnO in sputtering system. The ZnO thin films were grown at low temperature of $100^{\circ}C$ and at working pressure of 15 mTorr with RF magnetron sputtering. Having been gown, ZnO thin films were annealed in situ at different temperatures, at annealing ambient pressure of 15 mTorr and in ambients of oxygen and argon respectively. Through analyses of XRDs, it is can be concluded that the crystallinity of annealed ZnO thin films becomes much better than that of as-grown ZnO thin film.

• Progress in Superconductivity
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• v.5 no.2
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• pp.105-108
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• 2004

We have studied effects of in-situ annealing on the fabrication of superconducting MgB$_2$ thin films prepared by rf magnetron co-sputtering. The Films were deposited on A1$_2$O$_3$ (1102) substrates at room temperature by using Mg and B targets. To trap remnant $O_2$ gas in the chamber, we used 20 mtorr Af sputter-gas balanced with 5 mol % of H$_2$ gas. To enhance adhesion to the substrate a thin layer of B was deposited prior to the codeposition of Mg and B. After completion of the film deposition, an additional Mg layer was deposited on top to compensate for Mg loss during the subsequent in-situ annealing. We have investigated the effects of two most important annealing parameters that are the Mg-to-B composition ratio and the annealing temperature. The range of the Mg-to-B composition ratio was from 0.42 to 0.85, and that of the annealing temperature was 500 $^{\circ}C$∼750 $^{\circ}C$. The Best result was obtained for the composition ratio of about 10% Mg excess from the stoichiometry and the annealing temperature of 700 $^{\circ}C$. Based on these results, we obtained films with T$_{c}$ : 36.5 K by further refining the fabrication process.s.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.19 no.8
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• pp.769-774
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• 2006

In this paper the ZnO thin films, which has used spotlight of next generation short wavelength LEDs and semiconductor laser were deposited based on RF magnetron sputtering is described. The temperature at substrate and work pressure, which has implemented in sputtering process of ZnO thin films were settle down at $100^{\circ}C$ and 15 mTorr respectively. The ZnO 5N has used target. The thickness of ZnO thin films was about $1.6{\mu}m$ which was measured by SEM analysis after the sputtering process. Structural properties of ZnO thin films by in-situ and atmosphere annealing were analyzed by XRD. Transformation of grain size and surface roughness were observed by AFM. XPS spectra showed that ZnO thin film had a peak positions corresponding to the $Zn_{2p}$ and the $O_{1s}$. As form above XPS, we confirmed that post-annealing condition changed the atom ratio of Zn/O and microstructure in ZnO thin films.

• Proceedings of the KIEE Conference
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• 2000.07c
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• pp.1483-1484
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• 2000

Dielectric thin films of PLT(Pb(La.Ti)O3) for the application of highly integrated memory devices have been deposited on Pt/Ti/SiO2/Si substrates in situ by pulsed laser deposition(PLD). We have systematically investigated the variation of grain sizes depending on the condition of post-annealing and the variation of deposition rate. Both in-situ annealing and ex-situ annealing have been compared depending on the annealing time. C-V measurement, ferroelectric properties, leakage current and SEM were performed to investigate the electrical properties and the microstructural properties of Pb(La,Ti)$O_3$ films.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.13 no.10
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• pp.871-875
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• 2000

Effects of liquid crystal (LC) alignment using a in-situ photoalignment method by polarized UV exposure on a polyimide (PI) surface with medium side chain were studied. The generated pretilt angle in nematic(N) LC using a in-situ photoalignment method was smaller than that of a conventional photoalignment method for short UV exposure time. Also, the pretilt angle of NLC using a in-situ photoalignment method increases with increasing UV exposure time on the PI surfaces. Finally, the pretilt angle of NLC can be improved by annealing treatment.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2000.07a
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• pp.336-339
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• 2000

Effects of liquid crystal (LC) alignment using an in-situ photo-alignment method by linearly polarized UV exposure during imidization of polyirnide (PI) on the two kinds of PI surfaces with side chain were investigated. The generated pretilt angle in nematic (N) LC using an in-situ photo-alignment method was smaller than that of a conventional photo-alignment method for short UV exposure time. Also, the pretilt angle of the NLC using an in-situ photo-alignment method increases with increasing UV exposure time on the two kinds of the PI surfaces. Finally, the pretilt angle of NLC can be improved by annealing treatment.

• Korean Journal of Optics and Photonics
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• v.20 no.1
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• pp.34-40
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• 2009

In-situ pulse laser (Nd-YAG, 2nd harmonics 532 nm) annealing used in physical vapor deposition of $MgF_2$, $SiO_2$ and ZnS thin films was shown to be effective in improving their surface roughness properties. Total integrated scattering (TIS) measurements of $MgF_2$ and $SiO_2$ samples deposited on glass substrates revealed that the laser irradiation of films at an energy of approximately $140\;mJ/cm^2$ at 532 nm with a repetition frequency of 10 Hz and pulse duration of 5 ns during the deposition resulted in total scatterings that were minimum. But in case of the ZnS samples, measurements revealed minimum total scattering at a laser energy of approximately $62\;mJ/cm^2$. Atomic Force Microscopy (AFM) has been used to evaluate the effect of pulse laser annealing on the surface roughness for thin film samples. The results were similar to the TIS measurements, indicating that surface roughness was decreased when the irradiated annealing pulse laser energy increased. But it also increased when the irradiated annealing pulse laser energy was over some limit that depended on the materials.

• Proceedings of the KIEE Conference
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• 2000.11c
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• pp.416-418
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• 2000

Thin films of phase-pure perovskite $(Pb_{0.72}La_{0.28})Ti_{0.93}O_3$ (PLT) were deposited in-situ onto Pt/Ti/$SiO_2$/Si substrates by pulsed laser deposition. We have systematically investigated the variation of grain sizes depending on the process condition. Both in-situ annealing and ex-situ annealing treatments have been compared depending on the annealing time. The grain sizes of PLT thin films were successfully controlled 260 to 350 nm by changing process parameters. Microstructural and electrical properties of the film were investigated by C-V measurement, leakage current measurement and SEM. Two-step process to grow $(Pb_{0.72}La_{0.28})Ti_{0.93}O_3$ (PLT) films was adopted and verified to be useful to enlarge the grain size of the film and to enhance the leakage current characteristics.

• Journal of Information Display
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• v.1 no.1
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• pp.25-28
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• 2000

We propose a new in-situ fluorine passivation of poly-Si TFTs using excimer laser annealing to reduce the trap state density and improve reliability significantly. To investigate the effect of an in-situ fluorine passivation, we have fabricated fluorine-passivated p-channel poly-Si TFTs and examined their electrical characteristics and stability. A new in-situ fluorine passivation brought about an improvement in electrical characteristic. Such improvement is due to the formation of stronger Si-F bonds than Si-H bonds in poly-Si channel and $SiO_2$/Poly-Si interface.