• 제목/요약/키워드: surface passivation

검색결과 361건 처리시간 0.028초

$Se/NH_4OH$용액으로 처리시킨 n-GaAs의 Photoreflectance에 관한 연구 (A Study on Photoreflectance of n-GaAs Treated with$Se/NH_4OH$ Solution)

  • 김근형;김인수;이정열;이동건;배인호;박성배
    • E2M - 전기 전자와 첨단 소재
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    • 제10권6호
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    • pp.555-561
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    • 1997
  • The passivation of n-GaAs(100) surface has investigated by photoreflectance(PR). The surface of the sample was treated with the 0.001 N solution Se/NH$_4$OH. After the surface treatment, the samples were annealed between 400 to $700^{\circ}C$ in a $N_2$atmosphere for 10 min. The intensity of PR signal and period of Franz-Deldysh oscillation(FKO) gradually decreased as the annealing temperature increased. The surface electric field(E$_{s}$) of the sample annealed at $600^{\circ}C$ is obtained 1.34$\times$10$^{5}$ V/cm. This value is 1.97 times less than that of unannealed sample. It has found that the passivation of surface occurred when the surface of the sample had been treated with Se/NH$_4$OH solution and annealed from 500 to $600^{\circ}C$. This result could be due to activation of elemental Se on the surface. It has also found that the elemental Se of the surface diffused about 100 $\AA$ into the bulk GaAs when Se-treated sample was annealed at $600^{\circ}C$.>.

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Metamorphic HEMT에서 low-k Benzocyclobutene(BCB)를 이용한 표면 passivation 비교 연구 (Comparative Study of surface passivation for Metamorphic HEMT using low-k Benzocyclobutene(BCB))

  • 백용현;오정훈;한민;최석규;이복형;이성대;이진구
    • 대한전자공학회논문지SD
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    • 제44권4호
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    • pp.80-85
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    • 2007
  • Passivation 기술은 소자를 외부 환경의 영향으로부터 보호할 수 있고, 소자 성능의 감소를 예방할 수 있기 때문에 능동 소자 제작에 있어서 매우 중요하다. 본 논문에서 passivation 물질로 낮은 유전 상수를 갖는 benzocyclobutene (BCB)과 전통적인 passivation 물질인 Si3N4를 이용하여 GaAs를 기반으로 하는 $0.1{\mu}m\;{\Gamma}$-gate InAlAs/InGaAs metamorphic high electron mobility transistors (MHEMTs)를 제작하였다. 제작된 MHEMT의 특성은 passivation 전과 후로 구분하여 비교하였다. Passivation후 BCB와 Si3N4를 이용한 경우 모두에서 passivation 이전에 비해 저하된 DC 및 RF 특성을 나타내었으나, BCB를 이용하여 passivation을 한 소자들이 전통적인 passivation 물질인 Si3N4를 이용한 소자들에 비해서 상대적으로 낮은 특성 저하를 DC와 RF에서 함께 나타내었다.

VHF-CVD를 이용한 a-Si:H/c-Si 이종접합태양전지 표면 패시배이션 연구 (Surface passivation study of a-Si:H/c-Si heterojunction solar cells using VHF-CVD)

  • 송준용;정대영;김경민;박주형;송진수;김동환;이정철
    • 한국신재생에너지학회:학술대회논문집
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    • 한국신재생에너지학회 2011년도 춘계학술대회 초록집
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    • pp.128.1-128.1
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    • 2011
  • In amorphous silicon and crystalline silicon(a-Si:H/c-Si) heterojuction solar cells, intrinsic hydrogenated amorphous silicon(a-Si:H) films play an important role to passivate the crystalline silicon wafer surfaces. We have studied the correlation between the surface passivation quality and nature of the Si-H bonding at the a-Si:H/c-Si interface. The samples were obtained by VHF-CVD under different deposition conditions. The passivation quality and analysis of all structures studied was performed by means of quasi steady state photoconductance(QSSPC) methods and fourier transform infrared spectrometer(FTIR) measurements respectively.

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Surface Passivation Schemes for High-Efficiency c-Si Solar Cells - A Review

  • Balaji, Nagarajan;Hussain, Shahzada Qamar;Park, Cheolmin;Raja, Jayapal;Yi, Junsin;Jeyakumar, R.
    • Transactions on Electrical and Electronic Materials
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    • 제16권5호
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    • pp.227-233
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    • 2015
  • To reduce the cost of solar electricity, the crystalline-silicon (c-Si) photovoltaic industry is moving toward the use of thinner wafers (100 μm to 200 μm) to achieve a high efficiency. In this field, it is imperative to achieve an effective passivation method to reduce the electronic losses at the c-Si interface. In this article, we review the most promising surface passivation schemes that are available for high-efficiency solar cells.

Stainless Steel Foil Substrates; Robust, Low-Cost, Flexible Active-Matrix Backplane Technology

  • Hong, Yong-Taek;Heiler, Gregory;Cheng, I-Chun;Kattamis, Alex;Wagner, Sigurd
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2005년도 International Meeting on Information Displayvol.II
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    • pp.892-896
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    • 2005
  • In this paper, key issues of stainless steel foil substrates for display applications have been described. We studied and analyzed technical issues on substrate passivation/planarization to control surface roughness and capacitive coupling from conductive substrates. A thick (either multiple or single) passivation/planarization layer needs to be applied on the nonelectronic-grade stainless steel substrate to provide a smooth surface and electrical insulation from the conductive substrate. Especially for large size, high-resolution display applications, low k and thick passivation/planarization layers should be used for appropriate capacitive coupling. Based on our initial study, a unit area capacitance of less than $2nF/cm^2$ of passivation/planarization layers is needed for 32" HD TV OLED displays.

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Rear Surface Passivation with Al2O3 Layer by Reactive Magnetron Sputtering for High-Efficiency Silicon Solar Cell

  • Moon, Sun-Woo;Kim, Eun-Kyeom;Park, Won-Woong;Jeon, Jun-Hong;Choi, Jin-Young;Kim, Dong-Hwan;Han, Seung-Hee
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2012년도 제42회 동계 정기 학술대회 초록집
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    • pp.211-211
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    • 2012
  • The electrical loss of the photo-generated carriers is dominated by the recombination at the metal- semiconductor interface. In order to enhance the performance of the solar cells, many studies have been performed on the surface treatment with passivation layer like SiN, SiO2, Al2O3, and a-Si:H. In this work, Al2O3 thin films were investigated to reduce recombination at surface. The Al2O3 thin films have two advantages, such as good passivation properties and back surface field (BSF) effect at rear surface. It is usually deposited by atomic layer deposition (ALD) technique. However, ALD process is a very expensive process and it has rather low deposition rate. In this study, the ICP-assisted reactive magnetron sputtering method was used to deposit Al2O3 thin films. For optimization of the properties of the Al2O3 thin film, various fabrication conditions were controlled, such as ICP RF power, substrate bias voltage and deposition temperature, and argon to oxygen ratio. Chemical states and atomic concentration ratio were analyzed by x-ray photoelectron spectroscopy (XPS). In order to investigate the electrical properties, Al/(Al2O3 or SiO2,/Al2O3)/Si (MIS) devices were fabricated and characterized using the C-V measurement technique (HP 4284A). The detailed characteristics of the Al2O3 passivation thin films manufactured by ICP-assisted reactive magnetron sputtering technique will be shown and discussed.

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HWCVD 계면 보호층을 적용한 실리콘 이종접합 태양전지 연구 (Silicon Heterojunction Solar Cell with HWCVD Passivation Layer)

  • 박상현;정대영;김찬석;송준용;조준식;이정철;최덕균;윤경훈;송진수
    • 한국신재생에너지학회:학술대회논문집
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    • 한국신재생에너지학회 2009년도 추계학술대회 논문집
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    • pp.346-346
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    • 2009
  • For high efficiency hetero junction solar cell over 20%, good silicon wafer passivation is one of the most important technological factor. Compared to the conventional PECVD technique, HWCVD has appeared as an promising alternative for high quality passivation layer formation. In this work, HWCVD passivation layer characteristics have been intensively investigated on wafer surface treatment, Hydrogen density in deposited thin layer and thermal effects in deposition process. Comprehensive results of the individual process factors on interface passivation has been discussed and resultant silicon hetero junction solar cell characteristics has been investigated.

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Comparison of Surface Passivation Layers on InGaN/GaN MQW LEDs

  • Yang, Hyuck-Soo;Han, Sang-Youn;Hlad, M.;Gila, B.P.;Baik, K.H.;Pearton, S.J.;Jang, Soo-Hwan;Kang, B.S.;Ren, F.
    • JSTS:Journal of Semiconductor Technology and Science
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    • 제5권2호
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    • pp.131-135
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    • 2005
  • The effect of different surface passivation films on blue or green (465-505 nm) InGaN/GaN multi-quantum well light-emitting diodes (LEDs) die were examined. $SiO_2$ or $SiN_x$ deposited by plasma enhanced chemical vapor deposition, or $Sc_2O_3$ or MgO deposited by rf plasma enhanced molecular beam epitaxy all show excellent passivation qualities. The forward current-voltage (I-V) characteristics were all independent of the passivation film used, even though the MBE-deposited films have lower interface state densities ($3-5{\times}10^{12}\;eV^{-1}\;cm^{-2}$) compared to the PECVD films (${\sim}10^{12}\;eV^{-1}\;cm^{-2}$), The reverse I-V characteristics showed more variation, hut there was no systematic difference for any of the passivation films, The results suggest that simple PECVD processes are effective for providing robust surface protection for InGaN/GaN LEDs.

Al의 열산화 방법을 이용한 AlGaN/GaN 구조의 표면 Al2O3 패시베이션 효과 (Effect of Al2O3 Surface Passivation by Thermal Oxidation of Aluminum for AlGaN/GaN Structure)

  • 김정진;안호균;배성범;박영락;임종원;문재경;고상춘;심규환;양전욱
    • 한국전기전자재료학회논문지
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    • 제25권11호
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    • pp.862-866
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    • 2012
  • Surface passivation of AlGaN/GaN heterojunction structure was examined through the thermal oxidation of evaporated Al. The Al-oxide passivation increased channel conductance of two dimensional electron gas (2DEG) on the AlGaN/GaN interface. The sheet resistance of 463 ohm/${\Box}$ for 2DEG channel before $Al_2O_3$ passivation was decreased to 417 ohm/${\Box}$ after passivation. The oxidation of Al induces tensile stress to the AlGaN/GaN structure and the stress seemed to enhance the sheet carrier density of the 2DEG channel. In addition, the $Al_2O_3$ films formed by thermal oxidation of Al suppressed thermal deterioration by the high temperature annealing.

Passivation of organic light emitting diodes with $Al_2O_3/Ag/Al_2O_3$ multilayer thin films grown by twin target sputtering system

  • Jeong, Jin-A;Kim, Han-Ki
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2008년도 International Meeting on Information Display
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    • pp.420-423
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    • 2008
  • The characteristics of $Al_2O_3/Ag/Al_2O_3$ multilayer passivaton prepared by twin target sputtering (TTS) system for organic light emitting diodes. The $Al_2O_3/Ag/Al_2O_3$ multilayer thin film passivation on a PET substrate had a high transmittance of 86.44 % and low water vapor transmission rate (WVTR) of $0.011\;g/m^2$-day due to the surface plasmon resonance (SPR) effect of Ag interlayer and effective multilayer structure for preventing the intrusion of water vapor. Using synchrotron x-ray scattering and field emission scanning electron microscope (FESEM) examinations, we investigated the growth behavior of Ag layer on the $Al_2O_3$ layer to explain the SPR effect of the Ag layer. This indicates that an $Al_2O_3/Ag/Al_2O_3$ multilayer passivation is a promising thin film passivation scheme for organic based flexible optoelectronics.

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