• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2008년도 추계학술대회 논문집 Vol.21
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• pp.95-95
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• 2008

본 연구에서는 SiGe p-MOSFET을 제작하여 I-V 특성과 게이트 길이, $V_D$, $V_G$의 변화에 따른 저주파 노이즈특성을 측정하였다. Si 기판위에 성장한 $Si_{0.88}Ge_{0.12}$으로 제작된 SiGe p-MOSFET의 채널은 게이트 산화막과 20nm 정도의 Si Spacer 층으로 분리되어 있다. 게이트 산화막은 열산화에 의해 70$\AA$으로 성장되었고, 게이트 폭은 $25{\mu}m$, 게이트와 소스/드레인 사이의 거리는 2.5때로 제작되었다. 제작된 SiGe p-MOSFET은 빠른 동작 특성, 선형성, 저주파 노이즈 특성이 우수하였다. 제작된 SiGe p-MOSFET의 ESD 에 대한 소자의 신뢰성과 내성을 연구하기 위하여 SiGe P-MOSFET에 ESD를 lkV에서 8kV까지 lkV 간격으로 가한 후, SiGe P-MOSFET의 I-V 특성과 게이트 길이, $V_D$, $V_G$의 변화에 따른 저주파 노이즈특성 변화를 분석 비교하였다.

• 한국주조공학회지
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• 제22권1호
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• pp.42-48
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• 2002

Effects of coating treatment of metallic Cu, Ni-P film on $SiC_p$, for $SiC_p$/iron aluminide composites were studied. Porous hybrid preforms were fabricated by reactive sintering after mixing the coated $SiC_p$, Fe and Al powders. Then the final composites were manufactured by squeeze casting after pouring AC4C Al alloy melts in preforms. The change of reactive temperature, density, microstructure of the preforms and microstructure of the composites were investigated. The exprimental results were summarized as follows. The thickness of Cu and Ni-P metallic layer formed on $SiC_p$ by electroless plating method were about $0.5{\mu}m$ and coated uniformly. There was no remakable change in the ignition temperature with variation of the mixing ratio of Fe and Al powder while in the case of coated $SiC_p$ it was lower about $20^{\circ}C$ than in the non-coated $SiC_p$. The maximum reaction temperature increased with increasing Al contents, but decreased with increasing $SiC_p$ contents. Expansion ratio of preform after reactive sintering increased with amount of Cu coated $SiC_p$. In the case of Fe-70at.%Al, the expansion ratio was about 7% up to 8wt.% of $SiC_p$, addition but further addition of $SiC_p$, increased the ratio significantly. And in the case of Fe-50 and 60at.%Al, it was about 20% up to 16wt.% of $SiC_p$ addition and about 28% in 24wt.% of $SiC_p$, addition. The microstructures of compounds showed that the grains became finer as amount of $SiC_p$, and mixing ratio of iron powder increased and the shape of compounds was changed gradually from irregular to spheroidal.

• 한국정보전자통신기술학회논문지
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• 제16권4호
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• pp.180-186
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• 2023

본 논문은 4세대 VNAND 공정으로 만들어진 고전압 SiO2 절연층 nMOSFET의 n⁺ 및 p⁺ poly-Si 게이트에서의 positive bias temperature instability(PBTI) 열화에 대해 비교하고 각각의 메커니즘에 대해 분석한다. 게이트 전극 물질의 차이로 인한 절연층의 전계 차이 때문에 n⁺/nMOSFET의 열화가 p⁺/nMOSFET의 열화보다 더 클 것이라는 예상과 다르게 오히려 p⁺/nMOSFET의 열화가 더 크게 측정되었다. 원인을 분석하기 위해 각각의 경우에 대해 interface state와 oxide charge를 각각 추출하였고, 캐리어 분리 기법으로 전하의 주입과 포획 메커니즘을 분석하였다. 그 결과, p⁺ poly-Si 게이트에 의한 정공 주입 및 포획이 p⁺/nMOSFET의 열화를 가속시킴을 확인하였다.

• 한국세라믹학회지
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• 제30권6호
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• pp.433-440
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• 1993

The bioactivity of glasses in the CaO-SiO2 system and CaO-P2O5-SiO2 system with less than 10mol% of P2O5 was investigated by in vitro test in simulated body flood(SBF). The formation of Ca.P film and hydroxyapatite on the surface of glasses after in vitro test was analysed by X-ray photoelectron spectoscopy (XPS), fourier transform infrared reflection spectroscopy (FT-IRRS), energy dispersive X-ray spectroscopy (EDS), and scanning electron microscopy (SEM) observation. In the early stage of Ca.P film formation after in vitro test for CaO-SiO2 and CaO-P2O5-SiO2 glasses, the rate of Ca.P film formation on the surface of the glasses was dependent of structural parameter (Y) evaluated from the glass composition. First, in the case of the glasses having Y value below 2, Ca.P film and SiO2-rich layer were formed simultaneously, and there were no differences of the rate of Ca.P film formation in terms of the Y values. Second, in the case of the glasses having Y value above 2, the SiO2-rich layer was formed, and then Ca.P.Si mixed layer was formed in the silica gel structure of the SiO2-rich layer, and finally the Ca.P film on the surface of SiO2-rich layer. The rate of Ca.P film formation delayed as the Y values increased. The rate of hydroxyapatite formation of glasses (the rate of transformation from Ca.P film to hydroxyapatite) seems to be propotional to the rate of Ca.P film formation and Y value. The rate of hydroxyapatite formation of glasses belonging to the second group was delayed as structural parameter increased, and the hydroxyapatite crystal showed spherical growth in the early reaction stage, and then showed silkworm-like linear growth as the reaction time increased.

• 한국세라믹학회지
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• 제29권9호
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• pp.729-738
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• 1992

The glass formation and structural change with the glass compositions were investigated in the CaO-P2O5-SiO2 system with less than 40 wt% of P2O5. The glass formation range was determined by XRD, SEM and EDS techniques for water quenched specimens. The structural analyses were made for binary CaO-SiO2 glasses and ternary CaO-P2O5-SiO2 glasses by using FT-IR and Raman spectroscopy. The glass formation was affected by CaO/SiO2 mole ratio, P2O5 content and primary crystalline phase. The stable glass formation range was found when the transformed CaO/SiO2 mole ratio (new factor derived from structural changes) was in the range of 0.72~1.15 with less than 10 mol% of P2O5. The structural analyses of CaO-SiO2 glasses indicated that as the CaO/SiO2 ratio was increased, the nonbridging oxygens in the structural unit of the glasses were increased. With addition of P2O5 to CaO-SiO2 glasses, the P2O5 enhanced the polymerization of [SiO4] tetrahedra unit in CaO-SiO2 glasses, which contained a large portion of nonbridging oxygen. The phosphate eliminated nonbridging oxygens from silicate species, forcing polymerization of silicate structures and produced in [PO4] monomer in glasses. When added P2O5 was kept constant, the structural change with various CaO/SiO2 ratio was very similar to that of CaO-SiO2 glasses.

• 전기전자학회논문지
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• 제17권2호
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• pp.182-188
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• 2013

Using a ceramic target ZnO:In with In doping concentration of 2%, hetero-junctions of n-ZnO:In/p-Si and p-ZnO:(In, N)/n-Si were fabricated by depositing Indium doped n - type ZnO (ZnO:In or IZO) and Indium-nitrogen co-doped p - type ZnO (ZnO:(In, N)) films on wafers of p-Si (100) and n-Si (100) by DC magnetron sputtering, respectively. These films with the best electrical and optical properties were then obtained. The micro-structural, optical and electrical properties of the n-type and p-type semiconductor thinfilms were characterized by X-ray diffraction (XRD), RBS, UV-vis; four-point probe resistance and room-temperature Hall effect measurements, respectively. Typical rectifying behaviors of p-n junction were observed by the current-voltage (I-V) measurement. It shows fairly good rectifying behavior with the fact that the ideality factor and the saturation current of diode are n=11.5, Is=1.5108.10-7 (A) for n-ZnO:In/p-Si hetero-jucntion; n=10.14, Is=3.2689.10-5 (A) for p-ZnO:(In, N)/n-Si, respectively. These results demonstrated the formation of a diode between n-type thin film and p-Si, as well as between p-type thin film and n-Si..

• 한국진공학회:학술대회논문집
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• 한국진공학회 2016년도 제50회 동계 정기학술대회 초록집
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• pp.338.2-338.2
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• 2016

Al doped ZnO (AZO) thin films were deposited on Si substrates with rod-shaped-surface by pulsed laser deposition method (PLD). Si-rods were prepared through chemical etching. To analyze the influence on the formation of the rod structure, samples with various chemical etching conditions such as AgNO3/HF ratio, etching time, and solution temperature were prepared. The morphology of Si-rod structures were examined by FE-SEM. Fig. 1 shows a typical structure of n-AZO/p-Si-rod juncions. The fabricated n-AZO/p-Si-rod devices exhibited p-n diode current-voltage characteristics. We compared the I-V characteristics of n-AZO/p-Si-rod devices with the samples without Si-rod structure.

• 대한전자공학회논문지
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• 제14권1호
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• pp.15-22
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• 1977

자색광에 민감한 태양전지연구의 일환으로 우선 이러한 성질을 띤 광전지를 얻게 되었다. 이 광전지는 SnO2-SiO2-SiMOS와 Si n-p 동질접합이 결합된 구조로 되어 있다. 광전출력(0.25V, 150㎂)이 적어서 태양전지용은 못되지만 Si p-n 동질접합으로 된 태양전지에 비해서 분광감도가 자와선대쪽으로 이동되어 있고 switching 속도도 상당히 큰 고로 종래의 Si 광전지보다 더많은 새로운 용도를 찾아낼 수 있을 것으로 기대되고 있다.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2011년도 춘계학술대회 초록집
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• pp.110.2-110.2
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• 2011

일본 Sanyo 사에 의해서 획기적으로 HIT 태양전지가 개발된 바 있다. 이러한 HIT 태양전지는 기존의 확산-접합 Si 태양전지에 비해서 저비용 고효율의 장점을 갖는다: 22% 이상의 변환효율, $200^{\circ}C$ 이하의 공정온도, 낮은 태양전지 온도 의존도, 높은 개방전압. 한편 Sanyo사의 HIT 태양전지는 n-형 Si 웨이퍼를 이용한 반면에, 최근 미국 National Renewable Energy Laboratory는 p-형 Si 웨이퍼를 이용해서 변환효율 19% 대의 HIT 태양전지를 개발한 바 있다. 그 동안 지속적으로 p-형 Si HIT 태양전지를 고효율화하기(< 22%) 위해서 많은 노력이 진행되어 왔지만 이와 같은 노력에도 불구하고 아직 p-형 HIT는 n-형 HIT 태양전지에 비해서 다소 성능면에서 떨어져 있다. 본 연구는 n- 및 p-형 실리콘 웨이퍼로 구성된 HIT 태양전지의 물리적인 차이점에 초점을 맞추고, 결정 및 비정질 실리콘 층의 역할에 대해서 연구하였다. 특히 태양전지 효율을 향상시키는 요소들로서 결정 실리콘의 불순물 준위(n- 및 p-형) 또는 비저항, 비정질 실리콘으로 구성된 emitter 층, intrinsic 층, 경계면이 고려되었다. 그리고 이러한 요소들이 HIT 태양전지에 미치는 영향을 조사하기 위해서 AMPS-1D 컴퓨터 프로그램을 사용하였고, 이를 통해서 HIT 태양전지의 결정 및 비정질 실리콘 층의 역할을 물리적 정량적으로 분석하였다. 본 연구에 적용되는 HIT는 ITO/a-Si:H(p+)/a-Si:H(i)/c-Si(n)/a-Si:H(i)/a-Si:H(n+) 및 ITO/a-Si:H(n+)/a-Si:H(i)/c-Si(p)/a-Si:H(i)/a-Si:H(p+)의 구조로서 다음과 같은 태양전지 특성을 갖는다: n-형 HIT의 경우, fill factor ~ 0.78, 단락전류밀도 ~ 38.1 $mA/cm^2$, 개방전압 0.74 V, 변환효율 22.3 % (그리고 p-형 HIT의 경우, fill factor ~ 0.76, 단락전류밀도 ~ 36.5 $mA/cm^2$, 개방전압 0.69 V, 변환효율 19.4 %).

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2009년도 춘계학술대회 논문집
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• pp.77-79
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• 2009

Amorphous/crystalline silicon heterojunction solar cells, TCO/a-Si:H (p)/c-Si(n)/a-Si:H(n)/Al, are investigated. The influence of various parameters for the front structures was studied. We used thin (10 nm) a-Si:H(p) layers of amorphous hydrogenated silicon are deposited on top of a thick ($500{\mu}m$) crystalline c-Si wafer. This work deals with the influence of the a-Si:H(p) doping concentration on the solar cell performance is studied.