• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.18 no.11
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• pp.977-982
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• 2005

Al/AlN/n-type 6H-SiC (0001) MIS structures were prepared by AlN layers on vicinal 6H-SiC(0001) substrates with reactive RF magnetron sputtering method. The AlN films were annealed at $900^{\circ}C$, $N_2$ atmosphere lot 1 minutes showed the best result. With XRD analysis, AlN(0002) peak was clearly found. The typical dielectric constant value of the AlN film in the MIS capacitors was obtained as 8.4 from photo C-V. Also, the gate leakage current density of the MlS capacitor was $10^{-10}\;A/cm^2$ order within the electric field of 1.8 MV/cm. Finally, the amount of interface trap densities, $D_{it}$, was evaluated as $5.3\times10^{10}\;eV^{-1}cm^{-2}$ at (Ec-0.85) eV.

• Korean Journal of Materials Research
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• v.30 no.2
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• pp.99-104
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• 2020

Recent discoveries of ferroelectric properties in ultrathin doped hafnium oxide (HfO₂) have led to the expectation that HfO₂ could overcome the shortcomings of perovskite materials and be applied to electron devices such as Fe-Random access memory (RAM), ferroelectric tunnel junction (FTJ) and negative capacitance field effect transistor (NC-FET) device. As research on hafnium oxide ferroelectrics accelerates, several models to analyze the polarization switching characteristics of hafnium oxide ferroelectrics have been proposed from the domain or energy point of view. However, there is still a lack of in-depth consideration of models that can fully express the polarization switching properties of ferroelectrics. In this paper, a Zr-doped HfO₂ thin film based metal-ferroelectric-metal (MFM) capacitor was implemented and the polarization switching dynamics, along with the ferroelectric characteristics, of the device were analyzed. In addition, a study was conducted to propose an applicable model of HfO₂-based MFM capacitors by applying various ferroelectric switching characteristics models.

• Proceedings of the KIEE Conference
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• 1994.07b
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• pp.1463-1465
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• 1994

The electrical characteristics of $Al/Ta_2O_5/Si$ metal-oxide-semiconductor (MOS) capacitors were studied. $Ta_2O_5$ films on p-type silicon had been prepared by ionized cluster beam epitaxy technique (ICBE). This $Ta_2O_5$ films have low leakage current, high breakdown strength and low flat band shift. In this research, a single crystalline cpitaxial film of $Ta_2O_5$ has been grown on p-Si wafer using an ICBE technique. The native oxide layer ($SiO_2$) on the silicon substrate was removed below $500^{\circ}C$ by use of an accelerated arsenic ion beam, instead of a high temperature deposition. $Ta_2O_5$ films formed by ICBE technique can be received considerable attention for applications to coupling capacitors, gate dielectrics in MOS devices, and memory storage capacitor insulator because of their high dielectric constants above 20 and low temperature process.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.43 no.6 s.348
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• pp.1-8
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• 2006

In this paper, we designed a pixel circuit for AMOLED display based on organic thin film transistors and analyzed the operation with SPICE simulation. First, we theoretically designed the pixel circuit with the result of layout for fabricating $32\times32$ AMOLED panel, TFT W/L and capacitance of storage capacitor. And we simulated the designed pixel circuit using HSPICE for analyzing electrical performance. As a result of simulation, we identified the possibility of AMOLED display based on OTFTs.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1999.05a
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• pp.341-344
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• 1999

The effects of post annealing treatments of ferroelectrlclty in PZT(P $b_{1.05}$(Z $r_{0.52}$, $Ti_{0.48}$) $O_3$ thin film deposited on Pt/ $SiO_2$/Si substrate by RF-Magnetron sputtering methode was Investigated. Analyses by RTA(Rapid Thermal Annealing) treatments reveled that the crystallization process strongly depend on the healing temperature. The Perovskite structure with strong PZT (101) plan was obtained by RTA treatments at 75$0^{\circ}C$ With increasing RTA temperature of PZI thin films, the coercive field and remanent Polarization decreased, while saturation polarization( $P_{r}$) was decreased. P-E curves of Pt/PZT/Pt capacitor structures demonstrate typical hysteresiss loops. The measure values of $P_{r}$,. $E_{c}$ and dielectric constants by post annealed at 75$0^{\circ}C$ were 38 $\mu$C/$\textrm{cm}^2$ 35KV/cm and 974, respectively. Switching polarization versus fatigue characteristic showed 12% degradation up to 10$^{7}$ cycles.s.s.s.s.s.s.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2000.07a
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• pp.913-919
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• 2000

We give pressure stimulation into long chain fatty acid of LB thin films then manufacture a device under the accumulation condition that the state surface pressure is 20[mN/m]. In processing of a device manufacture, we can see the process is good from the change of a surface pressure for organic thin films and transfer ratio of area per molecule. The structure of manufactured device is Au/Arachidic acid/Al, the number of accumulated layers are 13, 17 and 19. The I-V characteristic of the device is measured from 0[V] to +1.5[V]. We have investigated the capacitance because this fatty acid system have a accumulated layers. The maximum value of measured current is increased as the number of accumulated layers are decreased. The capacitor properties of a thin film is better as the distance between electrodes is smaller. The results have shown the insulating materials and could control the conductivity by accumulated layers.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.11a
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• pp.394-397
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• 2001

In this paper, in-situ deposited Ru/RuO$_2$ bottom electrodes have been investigated as new bottom electrodes for PZT thin film capacitor application. As a comparison, structural and electrical properties of PZT thin films on Pt/Ti and RuO$_2$ bottom electrodes are also investigated. The use of Ru/RuO$_2$ hybrid electrodes showed better electrical properties in compression with RuO$_2$ bottom electrode. With increasing Ru electrode thickness, the PZT thin films showed preferred orientation along the (110) direction and leakage current of PZT thin films were improved. The PZT thin films on Ru (100nm)/RuO$_2$ electrodes exhibited excellent ferroelectric properties such as remant polarization and coercive field of 7.2 C/$\textrm{cm}^2$ and 46.35 kV/cm, respectively.

• Proceedings of the KIEE Conference
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• 2003.07c
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• pp.1502-1504
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• 2003

최근 전자기기의 경박단소화 추세는 전자기기의 크기와 가격의 감소를 이끌었으며 이러한 추세는 앞으로 지속될 것이다. 이와 같은 현상으로 전자기기를 구성하는 요소의 절반이상을 차지하는 단위수동소자의 경우 소형화를 넘어 박막화 및 집적화가 절실히 요구되는 실정이다. 따라서 본 연구에서는 현재 GHz 대역의 휴대용 무선통신 송 수신부 등에 사용되고 있는 기판이 $Al_2O_3$ 기판인 점을 고려하여 기판의 공통화를 위해 $Al_2O_3$ 기판 위에 Ta/$Ta_2O_5$/Ta 구조를 갖는 MIM 박막커패시터를 제작하여 그 특성을 고찰하였다. 모든 박막의 증착은 RF-magnetron reactive sputtering법에 의해 이루어졌으며, 유전체 열처리는 $700^{\circ}C$ 진공상태에서 60 sec 동안 수행하였다. XRD 분석결과, as-deposited $Ta_2O_5$ 박막은 열처리 후에 비정질상에서 결정질상으로 변환되었다. Ta/$Ta_2O_5$/Ta/Ti/$Al_2O_3$ 커패시터의 전기적 특성으로는 C-F, C-V, I-V 를 측정하였다.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2007.06a
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• pp.42-42
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• 2007

In the future, electronic components will be integrated on flexible polymer substrates and then miniaturized by thin films using suitable thin film technologies. In this article, the concept of a room temperature CVD is demonstrated using $Bi_3NbO_7$ (BNO) films with a cubic fluorite structure and their structural and electrical properties were investigated in films deposited without substrate heating. Effects of substrate temperature on electrical properties of BNO films were also studied. Films deposited without substrate heating (real temperature of $50^{\circ}C$) show partially crystallized BNO single phases with grain size of approximately 6.5 nm. Their dielectric and leakage properties are comparable to those of films deposited by pulsed laser deposition at room temperature. The concept of room temperature CVD will become a new paradigm in the deposition of dielectric thin films for flexible electron device applications.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2007.11a
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• pp.286-286
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• 2007

Li이 첨가된 0.7(Ba,Sr)$TiO_3$-0.3MgO 후막 interdigital 커패시터를 연구하였다. Li이 첨가된 0.7(Ba,Sr)$TiO_3$-0.3MgO의 후막을 $Al_2O_3$ 기판 위에 형성하기 위하여 스크린 프린팅 방법을 이용하였다. $BaSrTiO_3$의 세라믹 물질은 높은 유전율(1MHz에서 500이상)과 낮은 유전 손실(1MHz에서 0.01)값을 가지고 있는 반면, $1350^{\circ}C$의 높은 온도에서 소결되는 단점이 있다. 따라서 본 연구에서는 $BaSrTiO_3$ 세라믹 물질의 유전특성을 향상시키고 $1350^{\circ}C$의 높은 소결온도를 낮추기 위해서, MgO(30wt%)와 Li(3wt%)을 $BaSrTiO_3$에 첨가하였다. 그리고 10um의 후막을 $Al_2O_3$ 기판 위에 스크린 프린팅 방법을 통해 형성한 후, 50um finger gap의 interdigital 커패시터를 Ag 전극을 이용하여 제작하였다. 샘플을 제작하기 전에, Frequency와 유전율의 상관관계를 알아보기 위해 3D simulator를 통해 시뮬레이션 하였고, 주파수와 온도별 유전 특성, 구조와 전암-전류에 대한 특성을 본 연구의 결과를 통해 토의 할 것이다.