• 제목/요약/키워드: S-doping

검색결과 692건 처리시간 0.028초

보론 도핑에 따른 CdS 박막 및 CdS/CdTe 태양전지 특성 (Effects of Boron Doping on Properties of CdS Films and Characteristics of CdS/CdTe Solar Cells)

  • 이재형;이호열;박용관
    • 대한전기학회논문지:전기물성ㆍ응용부문C
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    • 제48권8호
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    • pp.563-569
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    • 1999
  • Boron doped CdS films were prepared by chemical bath deposition using boric acid$(H_3BO_3)$ as donor dopant source, and their electrical, optical properties were investigated as a function of doping concentration. In addition, effects of boron doping of CdS films on characteristics of CdS/CdTe solar cells were investigated. Boron doping highly decreased the resistivity and slightly increased optical band gap of CdS films. The lowest value of resistivity was $2 \Omega-cm \;at\; H_3BO_3/Cd(Ac)_2$ molar ratio of 0.1. For the molar ratio more than 0.1, however, the resistivity increased because of decreasing carrier concentration and mobility and showed similar value for undoped films. The photovoltaic characteristics of CdS/CdTe solar cells with boron doped CdS film improved due to the decrease of the conduction band-Fermi level energy gap of CdS films and the series resistance of solar cell.

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N- and P-doping of Transition Metal Dichalcogenide (TMD) using Artificially Designed DNA with Lanthanide and Metal Ions

  • Kang, Dong-Ho;Park, Jin-Hong
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2016년도 제50회 동계 정기학술대회 초록집
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    • pp.292-292
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    • 2016
  • Transition metal dichalcogenides (TMDs) with a two-dimensional layered structure have been considered highly promising materials for next-generation flexible, wearable, stretchable and transparent devices due to their unique physical, electrical and optical properties. Recent studies on TMD devices have focused on developing a suitable doping technique because precise control of the threshold voltage ($V_{TH}$) and the number of tightly-bound trions are required to achieve high performance electronic and optoelectronic devices, respectively. In particular, it is critical to develop an ultra-low level doping technique for the proper design and optimization of TMD-based devices because high level doping (about $10^{12}cm^{-2}$) causes TMD to act as a near-metallic layer. However, it is difficult to apply an ion implantation technique to TMD materials due to crystal damage that occurs during the implantation process. Although safe doping techniques have recently been developed, most of the previous TMD doping techniques presented very high doping levels of ${\sim}10^{12}cm^{-2}$. Recently, low-level n- and p-doping of TMD materials was achieved using cesium carbonate ($Cs_2CO_3$), octadecyltrichlorosilane (OTS), and M-DNA, but further studies are needed to reduce the doping level down to an intrinsic level. Here, we propose a novel DNA-based doping method on $MoS_2$ and $WSe_2$ films, which enables ultra-low n- and p-doping control and allows for proper adjustments in device performance. This is achieved by selecting and/or combining different types of divalent metal and trivalent lanthanide (Ln) ions on DNA nanostructures. The available n-doping range (${\Delta}n$) on the $MoS_2$ by Ln-DNA (DNA functionalized by trivalent Ln ions) is between $6{\times}10^9cm^{-2}$ and $2.6{\times}10^{10}cm^{-2}$, which is even lower than that provided by pristine DNA (${\sim}6.4{\times}10^{10}cm^{-2}$). The p-doping change (${\Delta}p$) on $WSe_2$ by Ln-DNA is adjusted between $-1.0{\times}10^{10}cm^{-2}$ and $-2.4{\times}10^{10}cm^{-2}$. In the case of Co-DNA (DNA functionalized by both divalent metal and trivalent Ln ions) doping where $Eu^{3+}$ or $Gd^{3+}$ ions were incorporated, a light p-doping phenomenon is observed on $MoS_2$ and $WSe_2$ (respectively, negative ${\Delta}n$ below $-9{\times}10^9cm^{-2}$ and positive ${\Delta}p$ above $1.4{\times}10^{10}cm^{-2}$) because the added $Cu^{2+}$ ions probably reduce the strength of negative charges in Ln-DNA. However, a light n-doping phenomenon (positive ${\Delta}n$ above $10^{10}cm^{-2}$ and negative ${\Delta}p$ below $-1.1{\times}10^{10}cm^{-2}$) occurs in the TMD devices doped by Co-DNA with $Tb^{3+}$ or $Er^{3+}$ ions. A significant (factor of ~5) increase in field-effect mobility is also observed on the $MoS_2$ and $WSe_2$ devices, which are, respectively, doped by $Tb^{3+}$-based Co-DNA (n-doping) and $Gd^{3+}$-based Co-DNA (p-doping), due to the reduction of effective electron and hole barrier heights after the doping. In terms of optoelectronic device performance (photoresponsivity and detectivity), the $Tb^{3+}$ or $Er^{3+}$-Co-DNA (n-doping) and the $Eu^{3+}$ or $Gd^{3+}$-Co-DNA (p-doping) improve the $MoS_2$ and $WSe_2$ photodetectors, respectively.

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대기압 플라즈마를 이용한 P타입 태양전지 웨이퍼 도핑 연구 (Study of P-type Wafer Doping for Solar Cell Using Atmospheric Pressure Plasma)

  • 윤명수;조태훈;박종인;김상훈;김인태;최은하;조광섭;권기청
    • Current Photovoltaic Research
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    • 제2권3호
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    • pp.120-123
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    • 2014
  • Thermal doping method using furnace is generally used for solar-cell wafer doping. It takes a lot of time and high cost and use toxic gas. Generally selective emitter doping using laser, but laser is very high equipment and induce the wafer's structure damage. In this study, we apply atmospheric pressure plasma for solar-cell wafer doping. We fabricated that the atmospheric pressure plasma jet injected Ar gas is inputted a low frequency (1 kHz ~ 100 kHz). We used shallow doping wafers existing PSG (Phosphorus Silicate Glass) on the shallow doping CZ P-type wafer (120 ohm/square). SIMS (Secondary Ion Mass Spectroscopy) are used for measuring wafer doping depth and concentration of phosphorus. We check that wafer's surface is not changed after plasma doping and atmospheric pressure doping width is broaden by increase of plasma treatment time and current.

Control of Short-Channel Effects in Nano DG MOSFET Using Gaussian-Channel Doping Profile

  • Charmi, Morteza
    • Transactions on Electrical and Electronic Materials
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    • 제17권5호
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    • pp.270-274
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    • 2016
  • This article investigates the use of the Gaussian-channel doping profile for the control of the short-channel effects in the double-gate MOSFET whereby a two-dimensional (2D) quantum simulation was used. The simulations were completed through a self-consistent solving of the 2D Poisson equation and the Schrodinger equation within the non-equilibrium Green’s function (NEGF) formalism. The impacts of the p-type-channel Gaussian-doping profile parameters such as the peak doping concentration and the straggle parameter were studied in terms of the drain current, on-current, off-current, sub-threshold swing (SS), and drain-induced barrier lowering (DIBL). The simulation results show that the short-channel effects were improved in correspondence with incremental changes of the straggle parameter and the peak doping concentration.

Si과 Mg Doping된 GaN 나노막대의 모양과 PL 특성 변화

  • 김경진;이상태;박병권;최효석;김문덕;김송강;오재응
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2013년도 제44회 동계 정기학술대회 초록집
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    • pp.459-459
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    • 2013
  • Si (111) 기판 위에 plasma assisted molecular beam epitaxy 법으로 Si과 Mg doping된 GaN 나노막대를 각 각 성장하고 나노막대의 모양과 광학적 특성을 조사하였다. Si이 doping된 GaN 나노막대는 biaxial m-plane 방향의 변화로 별 모양을 갖는 것을 관찰하였고 Mg doping된 GaN 나노막대의 지름은 줄어드는 것을 scanning electron microscopy로 확인하였다. 본 연구에서는 이러한 변화의 원인을 stress 때문으로 보고 x-ray diffraction과 raman scattering 측정을 통하여 구조적 변화를 조사하였다. 또한, stress에 의한 GaN 나노막대의광학적 특성 변화를 photoluminescence을 통하여 조사하였다. Doping한 GaN 나노막대의 특성조사를 통해 GaN 나노막대 성장 시 발생되는 stress의 영향을 이해하는데 중요한 정보를 제공할 것이다.

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도핑농도에 따른 다결정 3C-SiC 박막의 기계적 특성 (Mechanical properties of polycrystalline 3C-SiC thin films with various doping concentrations)

  • 김강산;정귀상
    • 센서학회지
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    • 제17권4호
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    • pp.256-260
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    • 2008
  • This paper describes the mechanical properties of poly(polycrystalline) 3C-SiC thin films with various doping concentration, in which poly 3C-SiC thin fil's mechanical properties according to the n-doping concentration 1($9.2{\times}10^{15}cm^{-3}$), 3($5.2{\times}10^{17}cm^{-3}$), and 5%($6.8{\times}10^{17}cm^{-3}$) respectively were measured by nano indentation. In the case of $9.2{\times}10^{15}cm^{-3}n$-doping concentration, Young's modulus and hardness were obtained as 270 and 30 GPa, respectively. When the surface roughness according to n-doping concentrations was investigated by AFM(atomic force microscope), the roughness of poly 3C-SiC thin films doped by 5% concentration was 15 nm, which is also the best of them.

Park Tae-hwan v. The Korean Olympic Committee: The Breakdown of Sports Jurisprudence in Korea

  • Phillips, Joe;Lim, Suk-Jun
    • 한국중재학회지:중재연구
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    • 제26권3호
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    • pp.93-119
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    • 2016
  • Park Tae-hwan, the Korean Olympic gold medal swimmer, was suspended for eighteen months by the International Swimming Federation (FINA) in September 2014. Park completed his suspension in March 2016, but the Korea Olympic Committee (KOC), relying on its Article 5.6, then prohibited him from joining the national team for an additional three years for the same doping violation. The KOC's penalty exceeded that provided by the World Anti-Doping Code, which governs the Olympics and most international sports federations, and contravened well-established precedent from the Court of Arbitration for Sport (CAS). The KOC, along with the Korea Swimming Federation, maintained the suspension until decisions by the Seoul Eastern District Court and CAS forced them to retract the penalty. We describe the sports regulations and arbitration decisions governing the Park case, how each side used the law to support their positions, the flaws in the KOC's legal analysis, and the case's resolutions by the Korean court and CAS. Finally, because this legal conflict has damaged the KOC's reputation, created uncertainty over the committee's doping penalties, and undercut the authority of the World Anti-Doping Code and the CAS in Korea, we recommend institutional changes in Korea's sports jurisprudence.

An Analysis Study on the Doping Intentions of Athletes using Stepwise Regression Analysis

  • Youn-Suk Han;Jong-Hwa Park
    • 한국컴퓨터정보학회논문지
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    • 제28권5호
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    • pp.171-177
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    • 2023
  • 본 연구는 다양한 이론적 접근을 통해 진행되어왔던 선행연구들을 바탕으로 국내 엘리트 선수들의 도핑 의도에 영향을 미치는 요인들을 파악하기 위해 단계적 회귀분석을 활용하여 운동경력 및 도핑교육 경험과 같은 인구통계학적 요인들과 통제적 동기, 도핑방지에 대한 태도 및 행동통제인식 요인과 도핑 의도의 관계를 규명함으로써 도핑방지에 중요한 정보를 제공하는데 목적이 있다. 연구의 목적을 달성하기 위해 SPSS 27.0 ver을 사용하여 분석하였다. 상관분석과 단계선택 회귀분석 사용하여 도출된 연구결과는 다음과 같다. 운동경력, 도핑 교육 경험 유·무, 통제적 동기, 도핑방지에 대한 태도 및 행동통제인식 요인 모두 도핑의도에 유의한 영향을 미치는 것으로 확인되었으며 이 중 영향력이 가장 큰 변인들을 각 순서대로 투입하여 유의한 영향이 있는지 검증하였다. 검증 결과 통제 동기가 가장 큰 영향을 미치는 것으로 나타났다. 다음으로는 도핑에 대한 행동통제인식, 도핑 교육 경험 유·무, 도핑에 대한 태도, 운동경력 순서대로 영향을 미치는 것을 확인하였다.

밀리미터파 PHEMT의 도핑층 설계에 따른 특성 변화 (The Effect of Doping Layer Structures on the Performance of Millimeter-wave PHEMT's)

  • 박훈;박진국;정지학;박현창
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2000년도 하계종합학술대회 논문집(2)
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    • pp.286-289
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    • 2000
  • PHEMT's with three different doping structures, -SH(single-heterojunction), DH (double-heterojunction), and DC(doped-channel)-,were designed, fabricated and characterized to study the effect of doping layer structures on the performance of millimeter-wave PHEMT's. 0.25${\mu}{\textrm}{m}$ DH-PHEMT with below-channel doping of 1$\times$10$^{12}$ c $m^{-2}$ was superior to SH-PHEMT by 40% in $I_{dss}$, 20% in f/sib T/ and showed broador gm- $I_{D}$ characteristics which is advantageous to power applications DH-PHEMT showed similar DC and small-signal performance compared with DC-PHEMT. Taking the much higher carrier mobility into considerations, DH-PHEMT is believed to be the best candidate for millimeter-wave, low-noise and/or power applications.s.s.

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