• Journal of the Institute of Electronics Engineers of Korea SD
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• v.39 no.7
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• pp.1-6
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• 2002

For an optimum device design of nano-scale SOI devices, this paper describes the short channel effects of multi-gate structures SOI MOSFETs such as double gate, triple gate and quadruple gate, as well as a new proposed Pi gate using computer simulation. The simulation has been performed with different channel doping concentrations, channel widths, silicon film thickness, and vertical gate extension depths of Pi gate. From the simulation results, it is found that Pi gate devices have a large margin in determination of doping concentrations, channel widths and film thickness comparing to double and triple gate devices because Pi gate devices offer a better short channel effects.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.7 no.3
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• pp.117-120
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• 2014

In general a main technology of control a sluice gate is accurate synchronous position control for the two cylinders when they are moving with the sluice gate together over 10[m]. Because the nonlinear friction and the unconstant supply flow. Cylinders' displacement will be different. In this case the sluice gate may be deformed and abraded, and even the sluice gate may unable to work. In order to design the controller for this system, we designed two kinds of Fuzzy PI controllers. Fuzzy PI position controller and Fuzzy PI synchronous controller have been designed. We show some simulation results for its availability.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.47 no.7
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• pp.1-7
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• 2010

The device performances of accumulation-mode Pi-gate pMOSFETs with different fin widths have been characterized at high operating temperatures. The device fin height is 10nm and fin widths are 30nm, 40nm, and 50nm. The variation of the drain current, threshold voltage, subthreshold swing, effective mobility, and leakage current have been investigated as a function of operating temperatures. The drain current at high temperature is slightly larger than at room temperature. The variation of the threshold voltage as a function of the operating temperature is smaller than that of the inversion-mode MOSFETs. The effective mobility is decreased with the increase of operating temperature. It is observed that the effective mobility is enhanced as the fin width decreases.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.22 no.12
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• pp.1009-1013
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• 2009

In this study, we have been synthesized the dielectric layer using pure organic and organic-inorganic hybrid precursor on flexible substrate for improving of the organic thin film transistors (OTFTs) and, design and fabrication of organic thin-film transistors (OTFTs) using small-molecule organic semiconductors with pentacene as the active layer with record device performance. In this work OTFT test structures fabricated on polymerized substrates were utilized to provide a convenient substrate, gate contact, and gate insulator for the processing and characterization of organic materials and their transistors. By an adhesion development between gate metal and PI substrate, a PI film was treated using $O_2$ and $N_2$ gas. The best peel strength of PI film is 109.07 gf/mm. Also, we have studied the electric characteristics of pentacene field-effect transistors with the polymer gate-dielectrics such as cyclohexane and hybrid (cyclohexane+TEOS). The transistors with cyclohexane gate-dielectric has higher field-effect mobility, $\mu_{FET}=0.84\;cm^2/v_s$, and smaller threshold voltage, $V_T=-6.8\;V$, compared with the transistor with hybrid gate-dielectric.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.28 no.11
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• pp.698-703
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• 2015

In this study, we fabricated the dual gate (DG) ion-sensitive field-effect-transistor (ISFET) with flexible polyimide (PI) extended gate (EG). The DG ISFETs significantly enhanced the sensitivity of pH in electrolytes from 60 mV/pH to 1152.17 mV/pH and effectively improved the drift and hysteresis phenomenon. This is attributed to the capacitive coupling effect between top gate and bottom gate insulators of the channel in silicon-on-transistor (SOI) metal-oxide-semiconductor (MOS) FETs. Accordingly, it is expected that the PI-EG based DG-ISFETs is promising technology for high-performance flexible biosensor applications.

• Journal of the Korean Institute of Intelligent Systems
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• v.20 no.1
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• pp.109-115
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• 2010

A main technology of opening and closing a sluice gate is accurate synchronous and position control for the two cylinders when they are moving with the sluice gate together over 10[m]. Since the supply flow and supply pressure of cylinders are not constant and a nonlinear friction force of the piston in cylinders exists, a difference will be made between the displacement of two cylinders. This difference causes the sluice gate to deform and abrade, and even it may be out of order. In order to solve this problem we design two kinds of fuzzy PI controllers. The former is for a position control of two cylinders, the latter is for their synchronous control. We show some simulation results compare the performance of fuzzy PI controller to the conventional PID controller.

• Korean Journal of Materials Research
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• v.28 no.4
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• pp.247-253
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• 2018

We examined the characteristics of indium tin zinc oxide (ITZO) thin film transistors (TFTs) on polyimide (PI) substrates for next-generation flexible display application. In this study, the ITZO TFT was fabricated and analyzed with a SiOx/SiNx gate insulator deposited using plasma enhanced chemical vapor deposition (PECVD) below $350^{\circ}C$. X-ray photoelectron spectroscopy (XPS) and secondary ion mass spectroscopy (SIMS) results revealed that the oxygen vacancies and impurities such as H, OH and $H_2O$ increased at ITZO/gate insulator interface. Our study suggests that the hydrogen related impurities existing in the PI and gate insulator were diffused into the channel during the fabrication process. We demonstrate that these impurities and oxygen vacancies in the ITZO channel/gate insulator may cause degradation of the electrical characteristics and bias stability. Therefore, in order to realize high performance oxide TFTs for flexible displays, it is necessary to develop a buffer layer (e.g., $Al_2O_3$) that can sufficiently prevent the diffusion of impurities into the channel.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.43 no.4 s.346
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• pp.23-30
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• 2006

This paper describes the short-channel effect(SCE), corner effect of nano-scale MuGFETs(Multiple-Gate FETs) by three-dimensional simulation. We can extract the equivalent gate number of MuGFETs(Double-gate=2, Tri-gate=3, Pi-gate=3.14, Omega-gate=3.4, GAA=4) by threshold voltage model. Using the extracted gate number(n) we can calculate the natural length for each gate devices. We established a scaling theory for MuGFETs, which gives a optimization to avoid short channel effects for the device structure(silicon thickness, gate oxide thickness). It is observed that the comer effects decrease with the reduction of doping concentration and gate oxide thickness when the radius of curvature is larger than 17 % of the channel width.

• 한국정보디스플레이학회:학술대회논문집
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• 2009.10a
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• pp.1243-1246
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• 2009

A novel a-Si TFT integrated gate driver circuit which suppresses the threshold voltage shift due to prolonged positive gate bias to pull-down TFTs, is reported. Negative gate-to-drain bias is applied alternately to the pull-down TFTs to recover the threshold voltage shift. Consequently, the stability of the circuit has been improved considerably.

• 한국정보디스플레이학회:학술대회논문집
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• 2005.07b
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• pp.1313-1316
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• 2005

In the present paper, it was investigated that adhesion layer on gate insulator could affect the electrical characteristics for the organic thin film transistors (OTFTs). The polyimide (PI) as organic adhesion layer was fabricated by using the vapor deposition polymerization (VDP) processing . It was found that electrical characteristics improved comparing OTFTs using adhesion layer to another. We researched adhesion layer as a function of thickness. For inverted-staggered top contact structure, field effect mobility, threshold voltage, and on-off current ratio of OTFTs using adhesion layer of PI 15 nm thickness on the gate insulator with a thickness of 0.2 ${\mu}m$ were about 0.5 $cm^2/Vs$, -0.8 V, and $10^6$, respectively.