• 제목/요약/키워드: S-doping

검색결과 694건 처리시간 0.026초

보론 도핑된 CdS 박막의 구조적 및 광학적 특성 (Effects of Boron Doping on the Structural and Optical Properties of CdS Thin Films)

  • Lee, Jae-Hyeong;Jung, Hak-Kee
    • 한국정보통신학회논문지
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    • 제7권5호
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    • pp.1032-1037
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    • 2003
  • 보론 도핑된 CdS 박막을 chemical bath deposition법으로 증착하고, 도핑농도에 따른 박막의 구조적, 광학적 특성을 조사하였다. 보론 도핑된 CdS 박막은 XRD 분석 결과 (002)면 방향으로 강한 우선성장 방위를 가지며 육방정(hexagonal) 구조로 성장하였다 보론 도핑에 관계없이 모든 시편은 2.3 eV(녹색 발광) 및 1.6 eV(적색 발광) 부근에서 PL peak을 가지며, 도핑 농도가 증가함에 따라 피크 세기는 감소하였다. 보론 도핑에 따라 CdS 박막의 가시광 영역에서의 광투과율은 향상되었고, 밴드 갭은 증가하였다.

CAS의 결정례로 본 도핑 위반 사건의 법리 (The Jurisprudence on Anti-Doping Rule Violation through Review of CAS Awards)

  • 김현숙
    • 한국중재학회지:중재연구
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    • 제28권1호
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    • pp.77-97
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    • 2018
  • The Court of Arbitration for Sport (CAS) has been adjudicating on sports-related disputes since 1984. CAS can be regarded as world supreme court for sports settling down about 4200 cases including doping issues. Doping disputes are generally processed by CAS Appeals division and Anti-Doping Division. An appeal against the decision by sports-related bodies may be filed with CAS Appeals Division. Doping issues concerning Olympic games are on Anti-Doping Division, introduced from 2016 Olympic games and invested with complete authority by IOC. The Award of Maria Sharapova finds a player is responsible if found to have committed any Anti-Doping Rule Violation regardless of his/her intention or fault. It offers detailed jurisprudence on imposing such a specific period of ineligibility in view of the totality of the circumstances. The award of Xinyi Chen also confirms the Strict Liability Rule on anti-doping disputes. The player appealed there could be either accidental contamination of drinks, or doping laboratories' mistakes that affected the test results. But, all of them were rejected. Though dealing with doping disputes in a timely manner is important for seasonal sports events like Olympic games, it is necessary to prepare the acceptable and fair process for the players in the future.

p-Type Doping of GaSb by Beryllium Grown on GaAs (001) Substrate by Molecular Beam Epitaxy

  • Benyahia, Djalal;Kubiszyn, Lkasz;Michalczewski, Krystian;Keblwski, Artur;Martyniuk, Piotr;Piotrowski, Jozef;Rogalski, Antoni
    • JSTS:Journal of Semiconductor Technology and Science
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    • 제16권5호
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    • pp.695-701
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    • 2016
  • Be-doped GaSb layers were grown on highly mismatched semi-insulating GaAs substrate (001) with $2^{\circ}$ offcut towards <110> at low growth temperature, by molecular beam epitaxy (MBE). The influence of Be doping on the crystallographic quality, surface morphology, and electrical properties, was assessed by X-ray diffraction, Nomarski microscopy, and Hall effect measurements, respectively. Be impurities are well behaved acceptors with hole concentrations as high as $9{\times}10^{17}cm^{-3}$. In addition, the reduction of GaSb lattice parameter with Be doping was studied.

Enhanced superconducting properties of MgB2 by doping the carbon quantum dots

  • K.C., Chung;S.H., Jang;Y.S., Oh;S.H., Kang
    • 한국초전도ㆍ저온공학회논문지
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    • 제24권4호
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    • pp.55-58
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    • 2022
  • Carbon-based doping to MgB2 superconductor is the simplest approach to enhance the critical current densities under magnetic fields. Carbon quantum dots is synthesized in this work as a carbon provider to MgB2 superconductors. Polyvinyl Pyrrolidone is pyrolyzed and dispersed in dimethylfomamide solvent as a dopant to the mixture of Mg and B powders. Doped MgB2 bulk samples clearly show the decrease of a-axis lattice constant, grain refinements, and broadening of FWHM of diffraction peaks compared to un-doped MgB2 possibly due to the carbon substitution and/or boron vacancy at the boron site in MgB2 lattice. Also, high-field Jc for the doped MgB2 is enhanced significantly with the crossover about 3 T at 5 & 20 K when increasing the doping of carbon quantum dots.

내부 도핑 법에 의한 Cu 도핑 Cu:ZnSe 양자점의 수계 합성 및 발광 특성 (Aqueous Synthesis and Luminescent Characteristics of Cu:ZnSe Quantum Dots by Internal Doping Method)

  • 백금지;홍현선
    • 한국분말재료학회지
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    • 제29권5호
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    • pp.370-375
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    • 2022
  • Cu-doped ZnSe quantum dots were successfully synthesized in an aqueous solution using an internal doping method. The effects of ligand type, CuSe synthesis temperature, and heating time on Cu-doped ZnSe synthesis were systematically investigated. Of MPA, GSH, TGA, and NAC used as ligands, MPA was the optimal ligand as determined by PL spectrum analysis. In addition, the emission wavelength was found to depend on the synthesis temperature of the internal doping core of CuSe. As the temperature increased, the doping of Cu2+ was enhanced, and the emission wavelength band was redshifted; accordingly, the emission peaks moved from blue to green (up to 550 nm). Thus, the synthesis of Cu:ZnSe using internal doping in aqueous solutions is a potential method for ecomanufacturing of color-tuned ZnSe quantum dots for display applications.

Ion Shower Doping Effect in Diamond and Diamond-Like Carbon Films

  • Jin Jang;Chun, Soo-Chul;Park, Kyu-Chang;Kim, Jea-Gak;Moon, Jong-Hyun;Park, Jong-Hyun;Song, Kyo-Jun;Lee, Seung-Min;Oh, Myung-Hwan
    • 한국진공학회지
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    • 제4권S2호
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    • pp.34-39
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    • 1995
  • we have studied the possibility of n-type doping in diamond and DLC films. After ion doping of either p-type or n-type, the electrical conductivities were remarkably increased and conductivity activation energies were decreased. The Raman intensity at 1330 cm-1 decreases slightly by ion doping of $7.2\times 10^{16}\; \textrm{cm}^{-2}$. The increase in conductivity by ion doping appears to be arised from the combined effects by substitutional doping and graphitization by ion damage.

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Effects of metal contacts and doping for high-performance field-effect transistor based on tungsten diselenide (WSe2)

  • Jo, Seo-Hyeon;Park, Jin-Hong
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2016년도 제50회 동계 정기학술대회 초록집
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    • pp.294.1-294.1
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    • 2016
  • Transition metal dichalcogenides (TMDs) with two-dimensional layered structure, such as molybdenum disulfide (MoS2) and tungsten diselenide (WSe2), are considered attractive materials for future semiconductor devices due to its relatively superior electrical, optical, and mechanical properties. Their excellent scalability down to a monolayer based on the van der Waals layered structure without surface dangling bonds makes semiconductor devices based on TMD free from short channel effect. In comparison to the widely studied transistor based on MoS2, researchs focusing on WSe2 transistor are still limited. WSe2 is more resistant to oxidation in humid ambient condition and relatively air-stable than sulphides such as MoS2. These properties of WSe2 provide potential to fabricate high-performance filed-effect transistor if outstanding electronic characteristics can be achieved by suitable metal contacts and doping phenomenon. Here, we demonstrate the effect of two different metal contacts (titanium and platinum) in field-effect transistor based on WSe2, which regulate electronic characteristics of device by controlling the effective barreier height of the metal-semiconductor junction. Electronic properties of WSe2 transistor were systematically investigated through monitoring of threshold voltage shift, carrier concentration difference, on-current ratio, and field-effect mobility ratio with two different metal contacts. Additionally, performance of transistor based on WSe2 is further enhanced through reliable and controllable n-type doping method of WSe2 by triphenylphosphine (PPh3), which activates the doping phenomenon by thermal annealing process and adjust the doping level by controlling the doping concentration of PPh3. The doping level is controlled in the non-degenerate regime, where performance parameters of PPh3 doped WSe2 transistor can be optimized.

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The Analysis of Breakdown Voltage for the Double-gate MOSFET Using the Gaussian Doping Distribution

  • Jung, Hak-Kee
    • Journal of information and communication convergence engineering
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    • 제10권2호
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    • pp.200-204
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    • 2012
  • This study has presented the analysis of breakdown voltage for a double-gate metal-oxide semiconductor field-effect transistor (MOSFET) based on the doping distribution of the Gaussian function. The double-gate MOSFET is a next generation transistor that shrinks the short channel effects of the nano-scaled CMOSFET. The degradation of breakdown voltage is a highly important short channel effect with threshold voltage roll-off and an increase in subthreshold swings. The analytical potential distribution derived from Poisson's equation and the Fulop's avalanche breakdown condition have been used to calculate the breakdown voltage of a double-gate MOSFET for the shape of the Gaussian doping distribution. This analytical potential model is in good agreement with the numerical model. Using this model, the breakdown voltage has been analyzed for channel length and doping concentration with parameters such as projected range and standard projected deviation of Gaussian function. As a result, since the breakdown voltage is greatly changed for the shape of the Gaussian function, the channel doping distribution of a double-gate MOSFET has to be carefully designed.

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

  • 이윤명;정귀상
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2008년도 하계학술대회 논문집 Vol.9
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    • pp.368-369
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    • 2008
  • This paper describes the mechanical properties of poly(polycrystalline) 3C-SiC thin film with various doping concentration, in which poly 3C-SiC thin film's mechanical properties according to the n-doping concentration 1%$(9.2\times10^{15}cm^{-3})$, 3%$(5.2\times10^{17}cm^{-3})$, and 5%$(6.8\times10^{17}cm^{-3})$ respectively was measured by nano indentation. In the case of $9.2\times10^{15}^{-3}$ n-doping concentration, Young's Modulus and hardness were obtained as 270 GPa 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 film doped by 5% concentration was 15 nm, which is also the best of them.

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Dependency of the emission efficiency on doping profile of the red phosphorescent organic light-emitting diodes

  • 박원혁
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2016년도 제50회 동계 정기학술대회 초록집
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    • pp.224-224
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    • 2016
  • Many researchers have been tried to improve the performance of the phosphorescent organic light-emitting diode(PHOLED) by controlling of the dopant profile in the emission layer. In this work, as shown in Fig. 1 insert, a typical red PHOLED device which has the structure of ITO/NPB(50nm)/CBP(30nm)/TPBi(10nm)/Alq3(20nm)/LiF(0.8nm)/Al(100nm) is fabricated with a 5nm thick doping section in the emission layer. The doping section is formed by co-deposition of CBP and Ir(btp)2acac with a doping concentration of 8%, and it's location(x) is changed from HTL/EML interface to EML/HBL in 5nm steps. The current efficiency versus current density of the devices are shown in Fig. 1. By changing the location of doping section, as shown in Fig. 1 and 2, at x=5nm, the efficiency shows the maximum of 3.1 cd/A at 0.5 mA/cm2 and it is slightly decreased when the section is closed to HTL and slightly increased when the section is closed to HBL. If the doping section is closed to HTL(NPB) the excitons can be quenched easily to NPB's triplet state energy level(2.5eV) which is relatively lower than that of CBP(2.6eV). Because there is a hole accumulation at EML/HBL interface the efficiency can be increased slightly when the section is closed to HBL. Even the thickness of the doping section is only 5nm,. the maximum efficiency of 3.1 cd/A with x=5 is closed to that of the homogeneously doped device, 3.3 cd/A, because the diffusion length of the excitons is relatively long. As a result, we confirm that the current efficiency of the PHOLED can be improved by the doping profile optimization such as partially, not homogeneously, doped EML structure.

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