• 제목/요약/키워드: N.O.F.

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$RuO_2$ Related Schottky contact for GaN/AlGaN device

  • Jung, Byung-Kwon;Kim, Jung-Kyu;Lee, Jung-Hee;Hahm, Sung-Ho
    • 한국반도체및디스플레이장비학회:학술대회논문집
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    • 한국반도체및디스플레이장비학회 2002년도 추계학술대회 발표 논문집
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    • pp.85-90
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    • 2002
  • $RuO_2$/GaN and related contacts were investigated for Schottky contacts in GaN-Based optical and electronic devices. We demonstrated that an $RuO_2$ film forms a stable Schottky contact on a GaN layer with a barrier height (${\Phi}_B$) of 1.46 eV and transmittance of 70% in the visible and near UV region. $RuO_2$/GaN Schottky diode showed a breakdown at over -50V and leakage current of only 0.3 nA at -5V. The $RuO_2$/GaN Schottky type photodetector had the UV/Visible rejection ratio of over $10^5$ and the responsivity of 0.23 A/W at 330 nm. The $RuO_2$ gate AlGaN/GaN EFET exhibited high drain current ($I_d$) of 689.3 mA/mm and high transconductance ($g_m$) of 197.4 mS/mm. Cut-Off frequency ($f_t$) and maximum operating frequency ($f_{max}$) were measured as 27.0 GHz and 45.5 GHz, respectively.

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저온소결 (Zn0.8Mg0.2)TiO3 세라믹의 마이크로파 유전특성에 관한 연구 (A Study on Microwave Dielectric Properties of Low-Temperature Sintered (Zn0.8Mg0.2)TiO3 Ceramics)

  • 방재철;심우성
    • 한국전기전자재료학회논문지
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    • 제16권7호
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    • pp.604-610
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    • 2003
  • The effects of sintering additives such as B $i_2$ $O_3$ and $V_2$ $O_{5}$ on the microwave dielectric and sintering properties of (Z $n_1$$_{-xM}$ $g_{x}$)Ti $O_3$ system were investigated. Highly dense samples were obtained for (Z $n_{0.8}$M $g_{0.2}$)Ti $O_3$ at the sintering temperature range of 870~90$0^{\circ}C$ with B $i_2$ $O_3$ and $V_2$ $O_{5}$ additions of 〈1 wt.%, respectively. The microwave dielectric properties of (Z $n_{0.8}$M $g_{0.2}$)Ti $O_3$ with 0.45 wt.%B $i_2$ $O_3$ and 0.55 wt.% $V_2$ $O_{5}$ sintered at 90$0^{\circ}C$ were as follows : Q$\times$ $f_{o}$ = 50,800 GHz, $\varepsilon$$_{r}$ = 22, and $\tau$$_{f}$ = -53 ppm/$^{\circ}C$. In order to improve temperature coefficient of resonant frequency, Ti $O_2$ was added to the above system. The optimum amount of Ti $O_2$ was 15 moi.% when sintered at 87$0^{\circ}C$, at which we could obtain following results: Q$\times$ $f_{o}$ = 32,800 GHz, $\varepsilon$$_{r}$ = 26, and$\tau$$_{f}$ = 0 ppm/$^{\circ}C$.EX>.EX>.EX>.EX>.EX>.EX>.EX>.

N-(Diphenylmethylene)aminomethylphosphonate의 결정 구조 (The Crystal Structure of N-(Diphenylmethylene) aminomethylphosphonate)

  • 김문집;박호종;김대영
    • 한국결정학회지
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    • 제13권2호
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    • pp.86-90
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    • 2002
  • X-선 회절법을 이용하여 N-(Diphenylmethylene)aminomethylphosphonate의 결정 구조를 규명하였다. 이 결정의 결정계는 삼사정계이며 공간군은 P(equation omitted)이다. 단위포 상수는 a=8.967(2) (equation omitted), b=9.309(2) (equation omitted), c= 10.981(2) (equation omitted), α=101.42(2)°, β=92.22(2)°, γ=92.23(2)°, V=896.8(3) (equation omitted), T=296 K, Z=2, D/sub c/=1.227 Mgm/sup -3/이다. 회절반점들의 세기는 Enraf-Nonius CAD-4 Diffracto-meter로 얻었으며 MoKα선(λ=0.7107(equation omitted))을 사용하였다. 분자 구조는 직접법으로 풀었으며, F/sub o/>4σ(F/sub o/)인 979개의 독립 회절 데이터에 대하여 최소자승법으로 209개의 변수를 정밀화하여 최종 신뢰도 값 R=7.3%을 얻었다.

ODD-EVEN GRACEFUL GRAPHS

  • Sridevi, R.;Navaneethakrishnan, S.;Nagarajan, A.;Nagarajan, K.
    • Journal of applied mathematics & informatics
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    • 제30권5_6호
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    • pp.913-923
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    • 2012
  • The Odd-Even graceful labeling of a graph G with $q$ edges means that there is an injection $f:V (G)$ to $\{1,3,5,{\cdots},2q+1\}$ such that, when each edge $uv$ is assigned the label ${\mid}f(u)-f(v){\mid}$, the resulting edge labels are $\{2,4,6,{\cdots},2q\}$. A graph which admits an odd-even graceful labeling is called an odd-even graceful graph. In this paper, we prove that some well known graphs namely $P_n$, $P_n^+$, $K_{1,n}$, $K_{1,2,n}$, $K_{m,n}$, $B_{m,n}$ are Odd-Even graceful.

초박막의 $N_2O$ 어닐링한 터널링 산화막을 갖는 Flash Memory Cell의 SILC 특성 및 성능 (Performance and SILC Characteristics of Flash Memory Cell With Ultra thin $N_2O$ Annealed Tunneling Oxide)

  • 손종형;정정화
    • 전자공학회논문지D
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    • 제36D권10호
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    • pp.1-8
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    • 1999
  • 본 논문은 두께가 각각 다른 습식 산호막의 정전류 스트레스에 따른 SILC를 측정하여 SILC의 전도 mechanism 및 발생원인을 조사하였다. $N_2O$ 어닐링한 산화막의 SILC 특성도 조사하였다. 또한, 60A 두께의 $N_2O$ 어닐링한 터널링 산호막을 갖는 ,flash memory cell을 $0.25{\mu}m$ 설계규칙에 따라 제작하여 그 특성을 측정하였다. 그 결과, SILC의 발생 원인은 전기적 스트레스 인가에 따른 산호막내에 생성된 트랩 때문이며, SILC의 전도 mechanism은 전기장 세기가 8MV/cm 이하일 때 산호막 트랩을 경유한 modified F-N 터널링이 8MV/cm 이상일 때 전형적인 F-N터널링이 주도적임을 알 수 있었다. 60A의 $N_2O$ 어닐링한 산화막은 SILC에 대한 내성 측면에서 큰 개선 효과가 있음을 알 수 있었다. 또한 이 막을 flash memory cell의 터널링 산호막으로 이용할 경우, $10^6$회의 endurance와 10년 이상의 드레인 disturb가 보장되고 8V-프로그래밍이 가능한 특성을 얻을 수 있었다.

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Effects of endurance exercise under hypoxia on acid-base and ion balance in healthy males

  • Nam, Sang-Seok;Park, Hun-Young
    • 운동영양학회지
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    • 제24권3호
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    • pp.7-12
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    • 2020
  • [Purpose] This study was performed to investigate the acid-base and ion balance at rest and after exercise in healthy males under normoxia, moderate hypoxia, and severe hypoxia. [Methods] Ten healthy Korean males completed three different trials on different days, comprising exercise under normoxia (FiO2 = 20.9%, N trial), moderate hypoxia (FiO2 = 16.5%, MH trial), and severe hypoxia (FiO2 = 12.8%, SH trial). They undertook endurance exercise for 30 min on a cycle ergometer at the same relative exercise intensity equivalent to 80% maximal heart rate under all conditions. Capillary blood samples were obtained to determine acid-base and ion balance at rest and after exercise. [Results] Exercise-induced blood lactate elevations were significantly increased as hypoxic conditions became more severe; SH > MH > N trials (P = 0.003). After exercise, blood glucose levels were significantly higher in the SH trial than in the N and MH trials (P = 0.001). Capillary oxygen saturation (SCO2) levels were significantly lowered as hypoxic conditions became more severe; SH > MH > N trials (P < 0.001). The pH levels were significantly lower in the MH trial than that in the N trial (P = 0.010). Moreover, HCO3- levels were significantly lower in the SH trial than in the N trial, with significant interaction (P = 0.003). There were no significant differences in blood Na+, K+, and Ca2+ levels between the trials. [Conclusion] MH and SH trials induced greater differences in glucose, lactate, SCO2, pH, and HCO3- levels in capillary blood compared to the N trial. Additionally, lactate, SCO2, and HCO3- levels showed greater changes in the SH trial than in the MH trial. However, there were no significant differences in Na+, K+, and Ca2+ levels in MH and SH trials compared to the N trial.

C_{28}H_{41}N_4O_4Br\;{\cdot}\;2H_2O$의 결정구조 ([ $C_{28}H_{41}N_4O_4Br\;{\cdot}\;2H_2O$ ])

  • 김문집;이정아;조경진;최기영
    • 한국결정학회지
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    • 제15권2호
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    • pp.93-98
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    • 2004
  • X-선 회절법을 이용하여 C_{28}H_{41}N_4O_4Br\;{\cdo}t\;2H_2O$의 분자 및 결정구조를 해석하였다. 이 결정의 결정계는 Triclinic이고 공간군은 Pl이며, 단위포 상수 a=9.000(1) $\AA$, b=9.312(3) $\AA$, c=9.344(2) $\AA$, $\alpha=89.37(20)^{\circ},\;\beta=68.81(3)^{\circ},\;\gamma=84.70(4)^{\circ},\;V=726.7(8){\AA},\;T=298K,\;Z=1,\;D_c=1.402Mgm^{-3}$이다. 회절반점들의 세기는 Enraf-Nonius CAD4 Diffractometer로 얻었으며 사용한 X-선은 graphite로 단색화한 $MoK{\alpha}$$(\lambda=0.71073\;{\AA}$을 사용하였다. 분자구조는 Direct method로 풀었으며, $F_o>4{\sigma}(F_0)$인 2521개의 독립 회절 데이터에 대하여 최소 자승법으로 370개의 변수를 정밀화하여 최종 신뢰도 값 $R=5.95\%$를 얻었다.

AlN 분말합성에 있어서 LiF와 BaF$_2$ 첨가효과 (Effect of LiF and BaF2 Addition on Synthesis of AlN Powder)

  • 최병현;이창송;신태수;이종민
    • 한국세라믹학회지
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    • 제28권8호
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    • pp.647-653
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    • 1991
  • In order to synthesize fine AlN powder by the direct nitridation of Aluminum metal power added LiF and BaF2 as additives was heated at 150$0^{\circ}C$ for 3 hrs. in nitrogen gas with flow rate of 20 mι/sec. Additives are promoted the nitridation by prevented the aggromerate of powders when 3% LiF and 2% BaF2 were added to Al metal powder. Rate of nitridation was about 100% and average size of AlN powders were very fine such as 0.3 ${\mu}{\textrm}{m}$. Specific surface area of synthesized AlN powder was 3.95$m^2$/g and also O2 and N2 contents were 2.595% and 33.25%, respectively.

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ON CERTAIN SUBCLASS OF STARLIKE FUNCTIONS OF ORDER ${\alpha}\cdot$ AND TYPE $\beta$

  • Aouf, M.K.
    • East Asian mathematical journal
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    • 제5권1호
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    • pp.35-47
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    • 1989
  • Let $S_o*({\alpha},{\beta},{\mu})$ denote the class of functions $f(z)=a_1z-{\sum}{\limit}^{\infty}_{n=2}\;a_nz^n$ analytic in the unit disc $U=\{z:{\mid}z{\mid}<1\}$ and satisfying the condition $${\mid}\frac{\frac{zf'(z)}{f(z)}-1}{(1+\mu)\;\beta(\frac{zf'(z)}{f(z)}-\alpha)-(\frac{zf'(z)}{f(z)}-1)}\mid<1$$ for some $\alpha(0{\leq}{\alpha}<1),\;{\beta}(0<{\beta}{\leq}1),\;{\mu}(0{\leq}{\mu}{\leq}1)$ and for all $z{\in}U$. And it is the purpose of this paper to show a necessary and sufficient condition for the class $S_o*({\alpha},{\beta},{\mu})$, some results for the Hadamard products of two functions f(z) and g(z) in the class $S_o*({\alpha},{\beta},{\mu})$, the distortion theorem and the distortion theorems for the fractional calculus.

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