• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1999.05a
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• pp.505-508
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• 1999

The effect of the heat treatment on electrochromic properties of $MoO_3$ thin films is investigated by studing optical modulation, optical density, response time, and cyclic voltammetry. From the results of XRD analysis, heat-treated at $450^{\circ}C$ in air for 1 hour $MoO_3$ thin films are found to be crystalline while as-deposited film and heat-treated at low temperature (${\leq}300^{\circ}C$) are amorphous. The electrochrornic devices using as-deposited $MoO_3$ films exhibits good electrochromic properties compare to those using the heat treated $MoO_3$ films. It has shown that the heat-treatment affected the stability and the electrochromic properties of $MoO_3$ films.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.11 no.9
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• pp.705-710
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• 1998

Intrinsic gettering is usually to improve wafer quality, which is an important factor for reliable ULSI devices. In order to generate oxygen precipitation in lightly and heavily boron doped silicon wafers with or without high $^75 As^+$ ion implantation, the 2-step annealing method was adopted. After annealing, the were cleaved and etched with th Wright etchant. The morphology of cross section on samples was inspected by FESEM(field emission scanning electron microscopy). The morphology of unimplanted samples was rater rough than that of the implanted. Oxygen precipitation density observed by an optical microscope in lightly boron doped samples was about 3$\times10^6/cm^3$. However, in heavily boron doped samples, the density of oxygen precipitation was largest at $600^{\circ}C$ in 1st annealing, and decreased abruptly until $800^{\circ}C$, But it increased slightly at $1000^{\circ}C$ and was independent with the implantation.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1999.05a
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• pp.26-29
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• 1999

The I-V characteristics of the n-channel offset gated poly-Si TETs have been systematically investigated in order to analyse the effects of offset region. The on currents are reduced due to the series resistance by the offset length and there is no kink phenomenon in offset devices. The off currents of the offset gated TFTs are remarkably reduced to 10$^{-12}$ A independent of gate and drain voltage because the electric field is weakened by the increase of the depletion region width near the drain region. It is shown that the offset regions behave as a series resistance and reduce lateral and vertical electric field.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1999.05a
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• pp.263-266
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• 1999

Electrolunlinescent devices based on conjugated polymer emitting materials have been much attracted possible applications for multicolor flat panel display, since the conjugated polymers have a small band gap emitting obtained at a low driving voltage. In this paper, we fabricated the single layer EL device using poly(3-hexylthiophene) as emitting material Electroluminescence(EL) and I-V-L characteristics of indium-tin-oxide[ITO]P3HT/AI device with a various thickness were investigated. It was demonstrate that the I-V characteristics depend, not the voltage but the electric- field strength, The current is dependent on the electric filed and not on the applied voltage, indicating that the carriers are injected by a tunneling process. In the device, the barrier to hole injection is only 0.5eV and the barrier to electron injection is 1.5eV.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1999.05a
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• pp.609-612
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• 1999

Organic electroluminescent(EL) devices have received a great deal of attention due to their potential application as full-color displays. They are attractive because of their capability of multicolor emission, ease of fabrication, and operation at a low driving voltage. In this study, single and multiple quantum-well structures consisting of Eu(TTA)$_3$(bpy) complex well layer sandwiched between triphenyldiamine derivative (TPD) layers were fabricated and their photoluminescent electroluminescent characteristics were also investigated. Sharp emission at 616 nm has been observed from the Eu complex in multilayer, single and multiple quantum-well structures. Details on the explanation of electrical properties of these structures will be discussed.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1999.05a
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• pp.370-373
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• 1999

Si direct bonding (SDB) technology is very attractive for both Si-on-insulator(SOI) electric devices and MEMS applications because of its stress free structure and stability. This paper presents on- pre treatment conditions in Si wafer direct bonding, The paper resents on pre-bonding according to HF pre-treatment conditions in Si wafer direct bonding. The characteristics of bonded sample were measured under different bonding conditions of HF concentration, applied pressure and annealing temperature(200~ 100$0^{\circ}C$) after pre-bonding. The bonding strength was evaluated by tensile strength method. The bonded interface and the void were analyzed by using SEM and IR camera, respectively, Components existed in the interlayer were analyzed by using FT-IR. The bond strength depends on the HF pre-treatment condition before pre-bonding(Min 2.4kgf/$\textrm{cm}^2$~ Max : 14.kgf/$\textrm{cm}^2$)

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.16 no.8
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• pp.731-735
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• 2003

Ti-indiffused LiNbO$_3$waveguide have been used to various high speed optical device based on electro-optic effect such as modulators, switches, and sensor, etc. In order to high speed modulation of optical modulator have, one of the further devices, needed to increasing of electrode surrounding air by LiNbO$_3$dry etching because of impedance matching for optical and RF phase velocity between waveguide and electrode. We studied property of LiNbO$_3$dry etching after waveguide patterning lot optical modulation by using neutral loop discharge (NLD) plasma.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2003.05a
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• pp.17-22
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• 2003

HTS superconducting tapes are now commercially available for practical applications such as magnets and cables. Since superconductors in such applications are subjected to high mechanical loads that can significantly degrade the superconducting properties, mechanical properties and the strain tolerance known as the strain effect on superconducting properties are needed to be estimated for developing superconducting devices. The progress in technology achieved in the field of strain effect evaluation on the critical current of HTS tapes in various deformation modes is discussed in this study.

• Transactions on Electrical and Electronic Materials
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• v.12 no.4
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• pp.140-143
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• 2011

The growth and characterization of $In_{0.5}Ga_{0.5}As/In_{0.5}Al_{0.5}As$ narrow-gap inverted high electron mobility transistor structures, developed as a candidate material for spin-injection devices, are presented in this study. We have grown samples possessing surface $In_{0.5}Ga_{0.5}As$ channels of different thicknesses (30 nm and 60 nm) both with and without a thin 3 nm $In_{0.5}Ga_{0.5}As$ cap layer by using molecular beam epitaxy. We then investigated the in-plane transport properties as well as the Rashba spin-orbit coupling constant of the two-dimensional electron gas confined at the heterojunction interface.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.22 no.1
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• pp.7-11
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• 2009

In this study, p-channel silicon-oxide-nitride-oxide-silicon(SONOS) transistors are fabricated and characterized as an unit cell for NAND flash memory. The SONOS transistors are fabricated by $0.13{\mu}m$ low power standard logic process technology. The thicknesses of gate insulators are 2.0 nm for the tunnel oxide, 1.4 nm for the nitride layer, and 4.9 nm for the blocking oxide. The fabricated SONOS transistors show low programming voltage and fast erase speed. However, the retention and endurance of the devices show poor characteristics.