• Proceedings of the IEEK Conference
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• 2002.07b
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• pp.1125-1128
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• 2002

Tantalum pentoxide (Ta$_2$O$\sub$5/) is a candidate for use in metal-insulator-metal diode in switching devices for active-matrix liquid-crystal displays. The MIM diode with very low threshold voltage and perfect symmetry was fabricated. High quality Ta$_2$O$\sub$5/ thin films were obtained by using an anodizing method. Rutherford backscattering spectroscopy, transmission electron microscope observations, auger electron spectroscopy, ellipsometry measurements, and electrical measurements, such as current - voltage(I-V) measurements were performed to investigate Ta$_2$O$\sub$5/ films and their reliability and indicated that the obtained TaOx thin films were reliable Ta$_2$O$\sub$5/ films for the applications. Furthermore, in this paper, we discuss the effects of top-electrode metals and annealing conditions. The conduction mechanism of the leakage current and the symmetry characteristics related to the Schottky emission and Poole-Frankel effect are also discussed using the results of electrical measurements and conduction barrier theory.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1996.11a
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• pp.75-78
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• 1996

The deposition condition Gf TiN films as electrode was studied by sheet resistance, TiN depositon Thickness X-ray diffraction. TiN was made by reactively DC magnetron sputtering with varying $N_2$/Ar mixture gas and substrate temperature. After finding The deposition condition of TiN films, The samples with the structure of Cu/Ta$_2$O$_{5}$, TiN/Ta$_2$O$_{5}$Si, Cu/TiN/Ta$_2$O$_{5}$ Si were prepared and were measured I-V, C-V. As a results, it was found that when TiN was deposited in an $N_2$a results, it was found that when TiN was deposited in an $N_2$atmosphere its Sheet resistance is lower n than n V$_2$Ar mixtureixture

• The Korean Journal of Ceramics
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• v.6 no.1
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• pp.74-77
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• 2000

Ta-doped PZT thin films prepared by reactive co-sputtering method could be transformed into single grained perovskite structure utilizing physical etching of Pt bottom electrode. It is found that PZT perovskite phase on damaged (111) Pt electrode by IMD was more easily crystallized than random oriented Pt electrode and less crystallized than (111) Pt electrode. This shows that amorphized Pt electrode surface by IMD process has an effect on crystallization of PZT perovskite phase. 40$\mu\textrm{m}\times40\mu\textrm{m}$ square shape single grain PZT array could be obtained utilizing the difference of incubation time for nucleation of rosettes between ion damaged Pt and (111) oriented Pt electrode. Single grained PZT thin films show low leakage current density of $1\times10^{-7}$ A/$\textrm{cm}^2$ and high break down field of 440kV/cm. The loss of remanent polarization after $10^{11}$ cycles was less than 15% of initial value.

• Journal of the Korean Applied Science and Technology
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• v.35 no.4
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• pp.1338-1347
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• 2018

In this study, Ti-mesh based electrodes were fabricated for the application of anode to the electrolysis process for wastewater treatment using Pd electroless plating method. The removal performance of the prepared Pd / Ti-mesh electrode was evaluated as representative dye RO16, and the durability and performance were maximized by varying the electrode manufacturing conditions. As a result, it was confirmed that the coating condition had no significant effect on the performance, and that the heat treatment process greatly affected the performance and the durability was improved. In addition, we tried to maximize performance and durability by complexing Ir, Ru, and Ta. However, as the thickness of the layer increased due to the limitation of the coating method, the resistance increased and the performance decreased accordingly.

• Journal of the Korean Vacuum Society
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• v.12 no.1
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• pp.40-45
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• 2003

High quality $Ta_2O_5$ thin films have been obtained from the anodization of deposited tantalum (Ta). The as-deposited amorphous films of 750 $\AA$ thickness have excellent electrical properties. These properties include refractive indices 2.1~2.2 dielectric constants ~25, and leakage currents $10^{-8}$ /A$\textrm{cm}^{-2}$ at 1 MV$\textrm{cm}^{-1}$. We fabricated a MIM element with the $Ta_2O_5$ films. They have perfect current-voltage symmetry characteristics. A high performance MIM device was formed by newly developed processes based on our unique anodization and annealing treatment. The effects of various processing conditions (top-electrode metals, annealing conditions) on the MIM device performances will be extensively discussed throughout this work.

• Journal of Sensor Science and Technology
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• v.4 no.3
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• pp.80-88
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• 1995

This paper presents the fabrication of a metal-insulator-metal(MIM) antifuse structure consisting of insulators sandwiched between top electrode, Al, and bottom electrode, TiW and additionally studies on antifuse properties depending on the condition of insulator. The intermetallic insulators, prepared by means of sputter, comprised of silicon oxide and tantalum oxide. In such an antifuse structure, silicon oxide layer is utilized to decrease the leakage current and tantalum oxide layer, of which the dielectric strength is lower than that of silicon oxide, is also utilized to lower the breakdown voltage near 10V. Finally sufficient low leakage current, below 1nA, and low programming voltage, about 9V, could be obtained in antifuse device comprising $Al/Ta_{2}O_{5}(10nm)/SiO_{2}(10nm)/TiW$ structure and OFF resistance of 3$3.65M{\Omega}$ and ON resistance of $7.26{\Omega}$ could be also obtained. This $Ta_{2}O_{5}/SiO_{2}$ based antifuse structures will be promising for highly reliable programmable device.

• Proceedings of the Korean Vacuum Society Conference
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• 2014.02a
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• pp.276-276
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• 2014

High-performance, fully-transparent, and top-gated oxide thin-film transistor (TFT) was successfully fabricated with Ta2O5 high-k gate dielectric on a glass substrate. Through a self-passivation with the gate dielectric and top electrode, the top-gated oxide TFT was not affected from H2O and O2 causing the electrical instability. Heat-treated InSnO (ITO) was used as the top and source/drain electrode with a low resistance and a transparent property in visible region. A InGaZnO (IGZO) thin-film was used as a active channel with a broad optical bandgap of 3.72 eV and transparent property. In addition, using a X-ray diffraction, amorphous phase of IGZO thin-film was observed until it was heat-treated at 500 oC. The fabricated device was demonstrated that an applied electric field efficiently controlled electron transfer in the IGZO active channel using the Ta2O5 gate dielectric. With the transparent ITO electrodes and IGZO active channel, the fabricated oxide TFT on a glass substrate showed optical transparency and high carrier mobility. These results expected that the top-gated oxide TFT with the high-k gate dielectric accelerates the realization of presence of fully-transparent electronics.

• Journal of the Korean Society of Laryngology, Phoniatrics and Logopedics
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• v.11 no.2
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• pp.178-184
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• 2000

Laryngeal evoked EMG is the objective and quantitative method to measure the innervation of laryngeal muscle. If there is a mobility disorder of vocal cords, the cause and location of neural lesion co be understood by the laryngeal evoked EMG and if there is a vocal cord paralysis, the degree of recovery and the policy of treatment can be determined by it. Recently, the studies of reinnervation after recurrent laryngeal nerve injury have been actively carried out. Laryngeal evoked EMC is useful to these studies. The aim of study is to know whether noninvasive methods for stimulating the recurrent laryngeal nerve and for recording of compound action potential(CAP) using surface electrode are as useful as the invasive method using needle electrode. We obtained EMG of laryngeal muscle by various stimulating and recording methods : 1) Direct nerve stimulation by placing nerve cuff electrode made out of silastic tube and platinum wire and recording by insertion of hook wire electrode into posterior cricoarytenoid(PCA) and thyroarytenoid(TA) muscles, respectively. 2) Recording of compound action potential by surface electrode after stimulation of recurrent laryngeal nerve by the insertion of 27 gauge of needle electrode. 3) Recording of compound action potential by surface electrode after stimulating the recurrent laryngeal nerve by transcutaneous blunt rod electrode at tracheoesophageal groove. The amplitude, duration and latency of the CAP evoked by recurrent laryngeal nerve stimulation were compared among the three groups. The amplitude of CAP was smallest in the group recorded from posterior cricoarytenoid and hyroarytenoid muscle, and that recorded by surface electrode after stimulation by needle electrode was largest. The difference in amplitude between the group by hook wire recording and the two groups by surface electrode recording was significant statistically. There is no significant difference in duration and latency among three groups. Since the waveform of CAP from all three methods has similar duration, latency, we concluded that noninvasive method is a useful as invasive methods.

• JSTS:Journal of Semiconductor Technology and Science
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• v.1 no.4
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• pp.202-208
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• 2001

In Recent results suggested that doping $Ta_2O_5$ with a small amount of $TiO_2$ using standard ceramic processing techniques can increase the dielectric constant of $Ta_2O_5$ significantly. In this paper, this concept is studied using RTCVD (Rapid Thermal Chemical Vapor Deposition). Ti-doped $Ta_2O_5$ films are deposited using $TaC_{12}H_{30}O_5N$, $C_8H_{24}N_4Ti$, and $O_2$ on both Si and $NH_3$-nitrided Si substrates. An $NH_3$-based interface layer at the Si surface is used to prevent interfacial oxidation during the CVD process and post deposition annealing is performed in $H_2/O_2$ ambient to improve film quality and reduce leakage current. A sputtered TiN layer is used as a diffusion barrier between the Al gate electrode and the $TaTi_xO_y$ dielectric. XPS analyses confirm the formation of a ($Ta_2O_5)_{1-x}(TiO_2)_x$ composite oxide. A high quality $TaTi_xO_y$ gate stack with EOT (Equivalent Oxide Thickness) of $7{\AA}$ and leakage current $Jg=O.5A/textrm{cm}^2$ @ Vg=-1.0V has been achieved. We have also succeeded in forming a $TaTi_x/O_y$ composite oxide by rapid thermal oxidation of the as-deposited CVD TaTi films. The electrical properties and Jg-EOT characteristics of these composite oxides are remarkably similar to that of RTCVD $Ta_2O_5, suggesting that the dielectric constant of $Ta_2O_5$ is not affected by the addition of $TiO_2$.

• Journal of Korean Society of Environmental Engineers
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• v.38 no.6
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• pp.291-298
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• 2016

Electrochemical water treatment process as a useful treatment method for the removal of non-degradable matter has been consistently studied for several decades. Key process of electrochemical water treatment are oxidation reaction from an anode and reduction from a cathode. In this study, the effect of pre-treatment methods in the insoluble electrode manufacturing process for the water treatment has been evaluated for the life time of electrode The results of this study showed that pre-treatment methods of a base metal such as surface roughness, clean method and interlayer formation influenced to life time of electrode when the same condition (catalyst electrode layer coating method and material system) was applied for pre-treatment methods. This study was conducted by using $IrO_2/Ti$ electrode In the test of sand-blasting process, an electrode manufactured by using sanding media of different sizes resulted in the most effective electrode life time when the size of alumina was used for $212{\sim}180{\mu}m$ praticle size (#80). The most effective method was considered using arc plasma in the additional roughness control and cleaning process, sputtering method to form Ta type interlayer formation process.