• Title, Summary, Keyword: Doping

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Optimized doping density and doping profile of pn junction for using high power device

  • Jang, Geon-Tae
    • Proceeding of EDISON Challenge
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    • pp.347-349
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    • 2016
  • 본 논문에서는 dopant density에 의존적인 pn junction의 breakdown 특성을 향상시키기 위하여, doping density와 doping profile에 대하여 분석했다. Doping density와 doping profile은 역방향 junction breakdown voltage를 결정하는 중요한 요소인 공핍영역의 두께와 공핍영역 내에 인가되는 electric field를 결정한다. Uniform doping profile과 Gaussian doping profile을 비교했고, 고전압 환경에서 사용할 수 있는 소자를 제작하는데 더욱 적절한 doping profile과 doping 농도에 대해 기술했다.

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Method for Screening and Confirming Meldonium in Human Urine by High-Resolution Mass Spectrometry and Identification of Endogenous Interferences for Anti-Doping Testing

  • Kim, Yongseok;Jeong, Dawon;Min, Hophil;Sung, Changmin;Park, Ju-hyung;Son, Junghyun;Lee, Kang Mi;Kim, Ho Jun;Lee, Jaeick;Kwon, Oh-Seung;Kim, Ki Hun
    • Mass Spectrometry Letters
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    • v.8 no.2
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    • pp.39-43
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    • 2017
  • Meldonium is a drug for treating ischemia by expanding the arteries but it can also enhance the performance of sports players. The World Anti-Doping Agency (WADA) has included it in the list of prohibited substances since 2016. Meldonium is one of the challenging substances for anti-doping testing because it is difficult to recover by general liquid-liquid or solid phase extraction due to its permanent charge and high polarity. Therefore, high-performance liquid chromatography (HPLC) is currently used by injecting a diluted urine sample (known as the "dilute-and-shoot" strategy). There is no loss of target compounds in the extraction/cleanup procedure but its high matrix effect could interfere in their separation or detection from the endogenous urinary compounds. We report a single method using high-resolution mass spectrometry that can be used for both screening and confirmation, which follows the "dilute-and-shoot" strategy. In this method, the endogenous compounds' interfering peaks in the mass spectrum are separated at a high resolution of FWHM 140,000, and the results are suitable for substance detection following the WADA guidelines. The interferences in the obtained mass spectrum of the urine matrix are identified as acetylcholine, lysine, and glutamine by further analysis and database searching. Validation of the method is performed in routine anti-doping testing, and the limit of detection is 50 ng/mL. This method uses simple sample preparation and a general reverse phase HPLC column, and it can be easily applied to other substances.

LC-MS/MS Method for Simultaneous Analysis of Growth Hormone-Releasing Peptides and Secretagogues in Human Urine

  • Min, Hophil;Han, Boyoung;Sung, Changmin;Park, Ju-Hyung;Lee, Kang Mi;Kim, Ho Jun;Kim, Ki Hun;Son, Junghyun;Kwon, Oh-Seung;Lee, Jaeick
    • Mass Spectrometry Letters
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    • v.7 no.3
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    • pp.55-63
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    • 2016
  • Growth hormone (GH)-releasing peptides (GHRPs) and GH secretagogues (GHSs) are listed in the World Anti-Doping Agency (WADA) Prohibited List. In the present study, we developed and validated a method for the simultaneous analysis of seven GHRPs (alexamorelin, GHRP-1, -2, -4, -5, -6, and hexarelin) and three GHSs (anamorelin, ibutamoren, and ipamorelin) in human urine. Method validation was performed at minimum required performance levels specified by WADA technical documents (2 ng/mL) for all substances, and the method was validated with regard to selectivity (no interference), linearity (R2 > 0.9986), matrix effects (50.0%-141.2%), recovery (10.4%-100.8%), and intra- (2.8%-16.5%) and inter-day (7.0%-22.6%) precisions. The limits of detection for screening and confirmation were 0.05-0.5 ng/mL and 0.05-1 ng/mL, respectively.

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

  • Yun, Myoungsoo;Jo, Taehun;Park, Jongin;Kim, Sanghun;Kim, In Tae;Choi, Eun Ha;Cho, Guangsup;Kwon, Gi-Chung
    • Current Photovoltaic Research
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    • v.2 no.3
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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.

Analysis of Glycerol with Isolation of Endogenous Interferences using "Dilute and Shoot" Strategy and High-Resolution Mass Spectrometry in Human Urine for Antidoping Testing

  • Kim, Yongseok;Min, Hophil;Sung, Changmin;Park, Ju-hyung;Son, Junghyun;Lee, Kang Mi;Kim, Ho Jun;Lee, Jaeick;Kwon, Oh-Seung;Kim, Ki Hun
    • Mass Spectrometry Letters
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    • v.7 no.4
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    • pp.111-115
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    • 2016
  • Glycerol was identified and isolated from endogenous interferences during analysis of human urine using high-resolution mass spectrometry (HRMS) for doping control. Urinary sample preparation was simple; the samples were diluted with an organic solvent and then analyzed using a liquid chromatography-mass spectrometry ("dilute and shoot" method). Although the interfering ion peaks were observed at the similar retention time of glycerol, the inference could be identified by isolation with HRMS and further investigation. Thus, creatinine was identified as the endogenous interference for glycerol analysis and it also caused ion suppression resulting in the decrease of glycerol signal. This study reports the first identification and efficient isolation of endogenous interferences in human urine for "dilute and shoot" method. The information about ion suppression could be novel to prevent overestimation or a false result for antidoping analysis.

Unusual Non-magnetic Metallic State in Narrow Silicon Carbon Nanoribbons by Electron or Hole Doping

  • Lou, Ping;Lee, Jin-Yong
    • Bulletin of the Korean Chemical Society
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    • v.33 no.3
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    • pp.763-769
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    • 2012
  • We investigated the width (N) dependence on the magnetization of N-ZSiC NR with electron and hole doping on the basis of systematic DFT calculations. The critical values of the upper and down critical concentration to give the maximum and zero magnetic moment at edge Si/C atoms by electron/hole doping ($x_{up,e}$, $x_{down,e}$, $x_{up,h}$, and $x_{down,h}$) depend on the width of N-ZSiC NR. Moreover, due to $x_{up,e}\;{\neq}\;x_{up,h}$ and $x_{down,e}\;{\neq}\;x_{down,h}$, the electron and hole doping effect are asymmetry, i.e, the critical electron doping value ($x_{down,e}$) is smaller than the critical hole doping value ($x_{down,h}$) and is almost independent of the width of NZSiC NR though the other critical values of the electron and hole doping that influence the magnetization of N-ZSiC NR depend on the width. It was also found that at $x_{down,e}$ or $x_{down,h}$ doping, the N-ZSiC NR turns into unusual non-magnetic metallic state. The magnetic behavior was discussed based on the band structures and projected density of states (PDOS) under the effect of electron/hole doping.

New Doping Process for low temperature poly silicon TFT

  • Park, Kyung-Min;You, Chun-Gi;Kim, Chi-Woo
    • 한국정보디스플레이학회:학술대회논문집
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    • pp.303-306
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    • 2005
  • We report the self-aligned low temperature poly silicon (LTPS) TFT process using simple doping process. In conventional LTPS-TFT, the Lightly Doped Drain (LDD) doping and source/drain doping are processed separately by aligning the gate with the source and drain during the gate lithography step. This ne w process not only fabricates fully self-aligned low temperature poly silicon TFTs with symmetric LDD structure but also simplifies the process flow with combined source/drain doping and LDD doping in one step. LDD doping process can be achieved using only source/drain doping process according to the new structure. In this paper, the TFT characteristics of NMOS and PMOS using the new doping process will be discussed.

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The Influence of Demographic Information, Knowledge of Doping and Education of Anti-doping on Attitude toward Doping among Elite Handball Players (엘리트 핸드볼 선수들의 인구통계학적 특성 및 도핑 관련 정보가 도핑에 대한 태도에 미치는 영향)

  • Chu, Zhesen;Kim, Yong-Jae;Kim, Taegyu
    • Journal of Digital Convergence
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    • v.16 no.3
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    • pp.553-560
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    • 2018
  • This study aimed to quantify the attitude toward doping among handball players and to identify the influence of players' demographic information, knowledge of doping, education of anti-doping on the attitudes toward doping. 385 elite handball players (193 adolescent players, 165 adult players) were participated in this study and filled in the questionnaire about demographic information, knowledge of doping, education of anti-doping and Performance Enhancement Attitude Scale (PEAS). Collected data were analyzed by Stepwise multiple linear regression. Adult players were more generous about doping than adolescents, and, adolescent players' attitudes toward doping were influenced by their gender and age. In adults, attitudes toward doping were related with only the gender. These results would be useful information to develop the effective anti-doping strategy for handball play.

Doping Effects and Semiconductor Behaviors of the Dispersed p- and n- type Semiconductor Particles (분산된 p형 및 n형 반도체 입자의 도핑 효과와 반도체 동작)

  • 천장호;손광철;라극환;조은철
    • Journal of the Korean Institute of Telematics and Electronics A
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    • v.31A no.5
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    • pp.126-133
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    • 1994
  • Doping effects and semiconductor behaviors of the dispersed p- and n-Si, p- and n- GaAs particles in the aqueous electrolyte have been studied using microelectrophoretic, voltammetric and chronoamperometric techniques. The cations (K$^{+}$) are adsorbed on both the p- and n- Si particle surfaces regardless of the sign of space charges in the depletion layers, i.e. doping profiles. The surface states are negatively charged acceptor states. On the other hand, the anions (CI$^{-}$) are adsorbed on both the p- and n- GaAs particle surfaces regardless of the sign of space charges in the depletion layers, i.e. doping profiles. The surface states are positively charged donor states. Under the same conditions, electrophoretic mobilities, electrochemical processes, doping effects and related semiconductor behaviors of the Si and the GaAs particles are similar regardless of the doping profiles, i. e. dopants and doping concentrations. The doping effects and related semiconductor behaviors of the dispersed p- and n- type semiconductor particles are gradually lost with decreasing dimensions.

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