• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2003년도 추계학술대회 논문집 Vol.16
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• pp.360-363
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• 2003

In this paper, we investigated SiNx film as a buffer layer of TFT-FRAM. Buffer layers were prepared by two step process of a $N_2$ plasma treatment and subsequent $SiN_x$ deposition. By employing $N_2$ plasma treatment, interface traps such as mobile charges and injected charges were removed, hysteresis of current-voltage curve disappeared. After $N_2$ plasma treatment, a leakage current was decreased about 2 orders. From these results, it is possible to perform the plasma treating process to make a good quality buffer layer of MFIS-FET or capacitor as an application of non-volatile memory.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2002년도 춘계학술대회 논문집 센서 박막재료 반도체재료 기술교육
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• pp.111-118
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• 2002

A new lithium niobate optical modulator with a polymer buffer layer on Ni in-diffused optical waveguide is proposed for the fist time, successfully fabricated and examined at a wavelength of 1.3 mm. By determining the diffusion parameters of Ni in-diffused waveguide to achieve more desirable mode size which is well matched to the mode in the fiber, the detailed results on the achievement of high optical throughput are reported. In addition, the usefulness of polymer buffer layer which can be applicable to a buffer layer in Ni in-diffused waveguide devices is demonstrated. Several sets of channel waveguides fabricated on Z-cut lithium niobate by Ni in-diffusion were obtained and on which coplanar traveling-wave type electrodes with a polymer-employed buffer layer were developed by a conventional fabrication method for characterizing of electro-optical performances of the proposed device. The experimental results show that the measured half-wave voltage is of ~10 V and the total measured fiber-to-fiber insertion loss is of ~6.4 dB for a 40 mm long at a wavelength of =1.3 mm, respectively. From the experimental results, it is confirmed that the polymer-employed buffer layer in LiNbO3 optical modulator can be a substitute material instead of silicon oxide layer which is usually processed at a high temperature of over $300^{\circ}C$. Moreover, the fabrication tolerances by using polymer materials in LiNbO3 optical modulators are much less strict in comparison to the case of dielectric buffer layer.

• 방사성폐기물학회지
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• 제6권1호
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• pp.55-63
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• 2008

고준위폐기물처분장의 완충재 물질로 사용되는 팽윤성 점토는 방벽재로서 그 기능을 제대로 발휘하기 위해 오랫동안 물리 화학적으로 안정해야 한다. 팽윤성 점토의 장기건전성 관련인 자들을 검토하고, 처분장 성능에 대한 각 인자의 중요성을 평가하였다. 검토결과, 붕괴 열에 의한 온도상승, 지하수 화학, 콘크리트에 의한 pH 증가, 유기물과 미생물, 방사선 조사 및 기계적 교란은 완충재물질로서 팽윤성 점토의 장기건전성에 중요한 인자임을 확인하였다. 본 연구는 고준위폐기물 처분장에서 팽윤성 점토의 완충재 설계를 위한 기초자료로 유용하게 활용될 것이다.

• 한국전기전자재료학회논문지
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• 제15권7호
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• pp.564-569
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• 2002

Heteroepitaxial GaN films were grown on sapphire substrates in order to study the effects of the buffer layer's surface roughness and thermal treatment on the epitaxial layer's quality. For this, GaN buffer layers were grown at $550^{\circ}C$ with various TMGa flow rates and durations of growth, and annealed at $1010^{\circ}C$ for 3 min after the temperature was raised by 23 ~ $92^{\circ}C/min$, and then GaN epitaxial layers were grown at $1000^{\circ}C$. It has been found that the buffer layer's surface roughness and the thermal treatment condition are critical factors on the quality of the epitaxial layer. When a buffer layer was frown with a TMGa flow rate of $24\mu mole/min$ for 30 sec, the surface roughness of the buffer lather was minimum and when the thermal ramping rate was $30.6^{\circ}C/min$ on this layer, the successively grown epitaxial layer's crystalline and optical qualities were optimized with a specular morphology. The minimum full width at half maximum(FWHM) of GaN(0002) x-ray diffraction peak and that of near-band-edge(NBE) peak from a room temperature photoluminescence (PL) were 5 arcmin and 9 nm, respectively.

• 한국전기전자재료학회논문지
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• 제25권7호
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• pp.491-495
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• 2012

The effects of various buffer layers on the $In_2O_3$ transparent conducting films grown on glass substrates by radio-frequency reactive magnetron sputtering were investigated. The $In_2O_3$ thin films were deposited at $400^{\circ}C$ of growth temperature and 100% of oxygen flow rate. The optical, electrical, and structural and morphological properties of the $In_2O_3$ thin films subjected to buffer layers were examined by using ultraviolet-visible spectrophotometer, Hall-effect measurements, and X-ray diffractometer, respectively. The properties of $In_2O_3$ thin films showed different results, depending on the type of buffer layer. As for the $In_2O_3$ thin film deposited on ZnO buffer layer, the average transmittance was 89% and the electrical resistivity was $7.4{\times}10^{-3}\;{\Omega}cm$. The experimental results provide a way for growing the transparent conducting film with the optimum condition by using an appropriate buffer layer.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2002년도 추계학술대회 논문집 Vol.15
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• pp.534-537
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• 2002

We have studied conduction mechanism that is interpreted in terms of space charge limited current (SCLC) region and tunneling region. The OLEDs are based on the molecular compounds, N,N'-diphenyl-N,N'-bis(3-methylphenyl)-1,1'-biphenyl-4,4'-diamine (TPD) as a hole transport, tris (8- hydroxyquinolinoline) aluminum(III) $(Alq_3)$ as an electron injection and transport and emitting later, copper phthalocyanine (CuPc) and poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) and poly(vinylcarbazole) (PVK) as a buffer layer respectively. Al was used as cathode. We manufactured reference structure that has in ITO/TPD/$Alq_3$/Al. Buffer layer effects were compared to reference structure. And we have analyzed out luminance efficiency-voltage characteristics in ITO/Buffer layer/TPD/$Alq_3$/Al with buffer-layer materials.

• 한국전기전자재료학회논문지
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• 제18권5호
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• pp.439-444
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• 2005

We investigated the structural and electrical properties of BLT films grown on Si covered with $ZrO_{2}$ buffer layer. The BLT thin film and $ZrO_{2}$ buffer layer were fabricated using a metalorganic decomposition method. The electrical properties of the MFIS structure were investigated by varying thickness of the $ZrO_{2}$ layer. AES and TEM show no interdiffusion and reaction that suppressed using the $ZrO_{2}$ film as a buffer layer The width of the memory window in the C-V curves for the MFIS structure decreased with increasing thickness of the $ZrO_{2}$ layer. It is considered that the memory window width of MFIS is not affected by remanent polarization. Leakage current density decreased by about four orders of magnitude after using $ZrO_{2}$ buffer layer. The results show that the $ZrO_{2}$ buffer layers are prospective candidates for applications in MFIS-FET memory devices.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2007년도 하계학술대회 논문집 Vol.8
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• pp.240-241
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• 2007

In general, high temperature superconducting coated conductors have intermediary buffers layer consisting of seed, diffusion barrier and cap layers. Simplification of the oxide materials buffer architecture in the fabrication of high temperature superconducting coated conductors is required because the deposition of multi-layers buffer architecture leads to a longer manufacturing time and a higher cost process of coated conductors. Thus, single buffer layer deposition seems to be important for practical coated conductor manufacturing process. In this study, a single gradient layered buffer deposition process of YZO for low cost coated conductors has been tried using DC reactive sputtering technique. About several thick YZO gradient single buffer layers deposited by DC co-sputtering process were found to act as a diffusion layer.

• Nuclear Engineering and Technology
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• 제53권10호
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• pp.3359-3366
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• 2021

An engineered barrier system (EBS) for the deep geological disposal of high-level radioactive waste (HLW) is composed of a disposal canister, buffer material, gap-filling material, and backfill material. As the buffer fills the empty space between the disposal canisters and the near-field rock mass, heat energy from the canisters is released to the surrounding buffer material. It is vital that this heat energy is rapidly dissipated to the near-field rock mass, and thus the thermal conductivity of the buffer is a key parameter to consider when evaluating the safety of the overall disposal system. Therefore, to take into consideration the sizeable amount of heat being released from such canisters, this study investigated the thermal conductivity of Korean compacted bentonites and its variation within a temperature range of 25 ℃ to 80-90 ℃. As a result, thermal conductivity increased by 5-20% as the temperature increased. Furthermore, temperature had a greater effect under higher degrees of saturation and a lower impact under higher dry densities. This study also conducted a regression analysis with 147 sets of data to estimate the thermal conductivity of the compacted bentonite considering the initial dry density, water content, and variations in temperature. Furthermore, the Kriging method was adopted to establish an uncertainty metamodel of thermal conductivity to verify the regression model. The R² value of the regression model was 0.925, and the regression model and metamodel showed similar results.

• 터널과지하공간
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• 제32권1호
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• pp.59-77
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• 2022

현재 고준위방사성폐기물 처분을 위한 완충재의 설계 기준 온도는 100 ℃ 미만이기에 완충재의 열 분산 능력이 개선된다면 처분장의 처분 터널과 처분 공의 간격을 줄일 수 있다. 본 연구에서는 완충재의 열-수리-역학 성능 기준을 분석하고자 하였으며, 완충재의 열전도도를 개선할 수 있는 고기능 완충재의 연구 현황에 대해 알아보고자 하였다. 우선, 열전도도는 가능한 높아야 하며 완충재의 열전도도 값은 건조밀도, 함수비, 온도, 광물조성, 벤토나이트 유형에 영향을 받는다. 또한 완충재에 함유된 유기물은 처분용기의 부식 성능에 큰 영향을 미칠 수 있기에 완충재의 유기물 함량은 매우 낮아야 한다. 수리전도도는 근계암반보다 더 낮게 설정해야 하며, 완충재가 제 기능을 하기 위해 팽윤성이 적정해야 한다. 고기능 완충재 개발을 위해 대표적으로 모래, 흑연, 산화 흑연 등의 첨가제를 사용하며 흑연의 경우 모래보다 아주 적은 첨가량으로 열전도도를 크게 향상시킬 수 있다.