• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.07a
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• pp.347-350
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• 2001

A typical Mold method is to form a gate electrode, a gate oxide, and emitter tip after fabrication of mold shape using wet-etching of Si substrate. In this study, however, new Mold method using a side wall space structure is used in order to make sharper emitter tip with a gate electrode. Using LPCVD(low pressure chemical vapor deposition), a gate oxide and electrode layer are formed on a Si substrate, and then BPSG(Boro phospher silicate glass) thin film is deposited. After, the BPSG thin film is flowed into a mold as high temperature in order to form a sharp mold structure. Next TiN thin film is deposited as a emitter tip substance. The unfinished device with a glass substrate is bonded by anodic bonding techniques to transfer the emitters to a glass substrate, and Si substrate is etched using KOH-deionized water solution. Finally, we made sharp field emitter array with gate electrode on the glass substrate.

• Journal of the Korean Institute of Telematics and Electronics D
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• v.34D no.6
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• pp.43-49
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• 1997

Tungsten poycide has studied gate oxide reliability and dielectric strength charactristics as the composition of gate electrode which applied submicron on CMOS and MOS device for optimizing gate electrode resistivity. The gate oxide reliability has been tested using the TDDB(time dependent dielectric breakdwon) and SCTDDB (stepped current TDDB) and corelation between polysilicon and WSi$_{2}$ layer. iN the case of high intrinsic reliability and good breakdown chracteristics on polysilicon, confirmed that tungsten polycide layer is a better reliabilify properities than polysilicon layer. Also, hole trap is detected on the polysilicon structure meanwhile electron trap is detected on polycide structure. In the case of electron trap, the WSi$_{2}$ layer is larger interface trap genration than polysilicon on large POCL$_{3}$ doping time and high POCL$_{3}$ doping temperature condition. WSi$_{2}$ layer's leakage current is less than 1 order and dielectric strength is a larger than 2MV/cm.

• JSTS:Journal of Semiconductor Technology and Science
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• v.10 no.2
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• pp.152-159
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• 2010

We propose a semi-analytical current conduction model for depletion-mode n-type nanowire field-effect transistors (NWFETs) with top-gate structure. The NWFET model is based on an equivalent circuit consisting of two back-to-back Schottky diodes for the metal-semiconductor (MS) contacts and the intrinsic top-gate NWFET. The intrinsic top-gate NWFET model is derived from the current conduction mechanisms due to bulk charges through the center neutral region as well as of accumulation charges through the surface accumulation region, based on the electrostatic method, and thus it includes all current conduction mechanisms of the NWFET operating at various top-gate bias conditions. Our previously developed Schottky diode model is used for the MS contacts. The newly developed model is integrated into ADS, in which the intrinsic part of the NWFET is developed by utilizing the Symbolically Defined Device (SDD) for an equation-based nonlinear model. The results simulated from the newly developed NWFET model reproduce considerably well the reported experimental results.

• Journal of Sensor Science and Technology
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• v.15 no.2
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• pp.90-96
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• 2006

We have fabricated the Pd-blck/NiCr gate MISFET-type $H_2$ sensor to detect the hydrogen in atmosphere. A differential pair-type structure was used to minimize the intrinsic voltage drift of the MISFET. The Pd-black film was deposited in the argon environment by thermal evaporation. In order to eliminate the blister formation in the surface of the hydrogen sensing gate metal, Pd-black/NiCr double metal layer was deposited on the gate insulator. The scanning electron microscopy and the auger electron spectroscopy was used to analyze their surface morphology and basic structure. The Pd-black/NiCr gate MISFET has been shown high sensitivity and stability more than Pd-planar/NiCr gate MISFET.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2006.05a
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• pp.1044-1048
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• 2006

Nuclear power generation is very dangerous in occasion that skirt of structure by earthquake although it is high effective generation that can make a lot of energies with few raw material. when design, it must consider a lot of problems caused by an earthquake. The seismic analysis of the structure has been great concern in the engineering society with an effort to reduce the severe damages from an earthquake. So the earthquake resistant design is one of the crucial design procedures of a gate valve used in nuclear power generation. The gate valve which has the contact area between stem and bellows. Because of the contact area. The gate valve should be given high stress and frictional wear. In this thesis, Considering the gate valve which has some contact distance between stem and bellows. The gate valve which has some contact distance is analyzed by a commercial FEM code of Ansys and Then compared to the gate valve behavior which doesn't have contact distance.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2002.04a
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• pp.515-520
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• 2002

This paper begin a new approach in the water-gate controller using radio communication. The dissertation is on the controllable device development of water-gate in the remote distance from water-gate trough the transceiver by radio communication. The proposed water-gate control device is simple in structure, an suitable for implementation of water-gate control in the remote distance. The remote controller water-gate device inspected the up and down motion of water-gate through the LCD displayer, so that it was very safety driving about the surroundings information, over loading and position of water-gate, and so on.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2002.05a
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• pp.612-615
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• 2002

This paper begin a new approach in the water-gate control using radio communication. The dissertation is on the controllable device development of water-gate in the remote distance from water-gate trough the transceiver by radio communication. The proposed water-gate control device is simpe in structure, an suitable for implementation of water-gate control in the remote distance. The remote controller water-gate device inspected the up and down motion of water-gate through the LCD displayer, so that it was very safety driving about the surroundings imformation, over loading and position of water-gate, and so on.

• Journal of Electrical Engineering and Technology
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• v.12 no.4
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• pp.1619-1626
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• 2017

Electronic components that are used in high-level radiation environment require a semiconductor device having a radiation-hardened characteristic. In this paper, we proposed a radiation-hardened I-gate n-MOSFET (n-type Metal Oxide Semiconductors Field Effect Transistors) using a layout modification technique only. The proposed I-gate n-MOSFET structure is modified as an I-shaped gate poly in order to mitigate a radiation-induced leakage current in the standard n-MOSFET structure. For verification of its radiation-hardened characteristic, the M&S (Modeling and Simulation) of the 3D (3-Dimension) structure is performed by TCAD (Technology Computer Aided Design) tool. In addition, we carried out an evaluation test using a $Co^{60}$ gamma-ray source of 10kGy(Si)/h. As a result, we have confirmed the radiation-hardened level up to a total ionizing dose of 20kGy(Si).

• Computers and Concrete
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• v.29 no.4
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• pp.209-217
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• 2022

In order to analyze the static and dynamic structural characteristics of the Obermeyer gate under overflow conditions, the force characteristics and vibration characteristics of the shield plate structure are studied based on the fluid-solid coupling theory. In this paper, the effects of the flow rate, airbag pressure and overflow water level on the structural performance of shield plate of air shield dam are explored through the method of controlling variables. The results show that the maximum equivalent stress and total deformation of the shield plate decrease first and then increase with the flow velocity. In addition, they are positively correlated with the airbag pressure. What's more, we find that the maximum equivalent stress of the shield plate decreases first and then increases with the overflow water level, and the total deformation of the shield plate decreases with the overflow water level. What's more importantly, the natural frequency of the shield structure of the Obermeyer gate is concentrated at 50 Hz and 100 Hz, so there is still the possibility of resonance. Once the resonance occurs, the free edge of the shield vibrates back and forth. This work may provide a theoretical reference for the safe and stable operation of the shield of the Obermeyer gate.

• Proceedings of the IEEK Conference
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• 2000.11b
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• pp.41-44
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• 2000

Ultra large scale integrated circuit(ULSI) & complementary metal oxide semiconductor(CMOS) circuits require gate electrode materials such as meta] silicides, titanium-silicide for gate oxides. Many previous authors have researched the improvements sub-micron gate oxide quality. However, little has been done on the electrical quality and reliability of ultra thin gates. In this research, we recommend novel shallow trench isolation structure and two step TiSi$_{2}$ formation for sub 0.1${\mu}{\textrm}{m}$ gate oxide.