• 전자공학회논문지D
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• 제34D권12호
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• pp.46-53
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• 1997

The TMA gas sensors are fabricated with the ZnO-based thin films grown by a RF magnetron sputtering method. The hall effect measurement and AES analysis are carried out to investigate the effects of the sputtering gases and dopants which effect on the electrical resistivity and sensitivity to TMA gas. We measure the cfhanges of the surface carrier concentration, haall electron mobility, electrical resistivity, surface condition, and depth profile of the films. The ZnO-based thin film sensors sputtered in oxygen, or added with dopants showed a high sruface carrier concentration, film sensors sputtered in oxygen and doped with 4.0 wt.% $Al_{2}$O$_{3}$, 1.0 wt.% TiO$_{2}$, and 0.2 wt% v$_{2}$O$_{5}$ showed the highest surface carrier concentration of 5.952 * 10$^{20}$ cm$^{-3}$ , hall electron mobility of 176.7 cm$^{2}$/V.s, lowest electrical resistivity of 6*10$^{-5}$ .ohm.cm and highest sensitivity of 12. These results were measured at a working temperature of 300.deg. C to 8 ppm TMA gas.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2005년도 International Meeting on Information Displayvol.II
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• pp.1477-1479
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• 2005

In this work, the ITO thin films were prepared by FTS (Facing Targets Sputtering) system under different sputtering conditions which were varying $O_2$ gas flow, input current at room temperature. As a function of sputtering conditions, electrical and optical properties of prepared ITO thin films were measured. The electrical, optical characteristics and surface roughness of prepared ITO thin films were measured. In the results, as increasing $O_2$ gas 0.1[sccm] to 0.7[sccm], resistivity of ITO thin film was increased with a decreasing carrier concentration, $O_2$ gas over 0.3[sccm] the carrier mobility have a similarly value. Transmittance of prepared ITO thin films were improved at increasing $O_2$ gas 0.1[sccm] to 0.7[sccm]. And transmittance of all of the prepared ITO thin films was over 80%. We could obtain resistivity $6.19{\times}10^{-4}[{\omega}{\cdot}cm]$, carrier mobility $22.9[cm^2/V{\cdot}sec]$, carrier concentration $4.41{\times}10^{20}[cm^{-3}]$ and transmittance over 80% of ITO thin film prepared at working pressure 1mTorr, input current 0.4A without any substrate heating.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1996년도 춘계학술대회 논문집
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• pp.185-188
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• 1996

The doped n-type $Al_{x}Ga_{1-x}Sb$ crystals were grown by the vertical Bridgman method at composition ratio x=0, x=0.1, x=02 respectively. The lattice constants of the $Al_{x}Ga_{1-x}Sb$ crystals were 6.096${\AA}$, 6.097${\AA}$, 6.106${\AA}$ at composition ratio respectively. The carrier concentration, the resistivity, and the carrier mobility measured by the Van der Pauw method at x-0 were n≡1 x $10^{17}$$cm^{-3}$, $\rho$≡0.15 ${\Omega}$-cm, ${\mu}$$_{n}$≡500 $\textrm{cm}^2$$V^{-1}$$sec^{-1}$ at 300K. The carrier concentration, the resistivity, and the carrier mobility measured by the Van der Pauw method at x=0.1 were n≡2.96 x $10^{15}$$cm^{-3}$, $\rho$≡103 $\textrm{cm}^2$$V^{-1}$$sec^{-1}$ at 300K.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2010년도 제39회 하계학술대회 초록집
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• pp.53-53
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• 2010

Graphene comes into the spotlight as an emergent device material on account of its high carrier mobility reflecting its massless Dirac fermion behavior. Chemical technique to control reversibly the carrier concentration of semiconducting graphene for the achievement of a large-area graphene device has been strongly required. Here we show that the adsorptions of a metal and a molecule can manipulate the carrier concentration of single-layer graphene, epitaxially grown on SiC, which was directly observed using angle-resolve photoemission spectroscopy. These results will shed light on the researches for the very large scale integration of a graphene device. Furthermore, the carrier concentration changes can be applied to a highly sensitive gas sensor or a detector for an specific binding between an antigen and an antibody.

• 한국전기전자재료학회논문지
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• 제11권8호
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• pp.601-606
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• 1998

ZnO thin film had been deposited on the glass by sputtering method, and the electrical and structural properties were investigated. When the rf power was 180W and sputtering was 10 m Torr at room temperature, Al-doped ZnO thin film had the lowest resistivity(1$\times10^{-4}\Omega\cdot{cm}$) and then carrier concentration and Hall mobility were $6.27\times10^{20} cm^{-3} and 22.04 cm^2/V\cdot$s, respectively. The undoped ZnO thin film had about 10$\times10^{14}\Omega\cdot cm$ resistivity when oxygen content was 10% or more at room temperature. When the oxygen content was 50% and below and sputtering pressure was 1.0$\times$1.0 \ulcorner Torr, the surface morphology of thin film observed by SEM was overall uniform.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 1998년도 하계종합학술대회논문집
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• pp.327-330
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• 1998

In this theory, we explained the impossibility of the motion or miving of the hole that has been recognized to be a carrier, by giving some fundamental reasons. We treated energy gap and impurity concentration, in p- and n-type region, as functions of the mobility that is one of te factors which determine current quantity, and analyzed the primary electron theory as a carrier by introducing 2 hypotheses.

• 대한전자공학회논문지
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• 제5권1호
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• pp.1-5
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• 1968

GaAs의 단결정은 Ga의 용액으로부터 epitaxial 방법으로 성장시키는데 300°K에서는 carrier concentration 10 /㎤에서 electron-mobility 7,500∼9,300㎠/V-sec. 정도의 것이 얻어지며 77°K에서는 electron-mobility 50,000∼95,000㎠/V-sec.의 것이 얻어진다. mobility-온도 관계곡선의 이론적인 것과 실험적인 것을 비교해 보면 77°K에서 430°K의 온도범위내에서 ion화한 불순물과 phonon이 주요한 scattering mechanism이라는 것을 나타낸다. 이것은 epitaxial층이 mobility를 제한하는 다른 결함을 별로 내포하지 않는다는 것을 의미한다. epitaxial층의 photoluminescence spectra는 심부에 존재하는 결함의 준위에 의한 방출을 나타내지 않는다.

• 한국전기전자재료학회논문지
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• 제37권3호
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• pp.253-260
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• 2024

In this study, ITO thin films were fabricated on a glass substrate at different thicknesses without introducing oxygen using RF sputtering system. The structural, electrical, and optical properties were evaluated at various thicknesses ranging from 50 to 300 mm. As the thickness of deposited ITO thin film become thicker from 50 to 100 mm, carrier concentration, mobility, and band gap energy also increased while the resistivity and transmittance decreased in the visible light region. When the film thickness increased from 100 to 300 mm, the carrier concentration, mobility, and band gap energy decreased while the resistivity and transmittance increased. The optimum electrical properties were obtained for the ITO film 100 nm. After optimizing the thickness, the ITO thin films were post-annealed at different temperatures ranging from 100 to 300℃. As the annealing temperature increased, the ITO crystal phase became clearer and the grain size also increased. In particular, the ITO thin film annealed at 300℃ indicated high carrier concentration (4.32 × 10²¹ cm^-3), mobility (9.01 cm²/V·s) and low resistivity (6.22 × 10^-4 Ω·cm). This means that the optimal post-annealing temperature is 300℃ and this ITO thin film is suitable for use in solar cells and display application.

• E2M - 전기 전자와 첨단 소재
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• 제9권9호
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• pp.885-890
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• 1996

Undoped p-type and Te doped n-type GaSb crystals were grown by the vertical Bridgman method. The lattice constant of the GaSb crystals was 6.096.+-.000373.angs.. The carrier concentration, the resistivity, and the carrier mobility measured by the van der Pauw method were p.iden.8*10$^{16}$ c $m^{-3}$ , .rho..iden.0.20 .ohm.-cm, .mu.$_{p}$ .iden.400c $m^{2}$ $V^{-1}$ se $c^{-1}$ for p-type, n.iden.1*10$^{17}$ c $m^{-3}$ , .rho..iden.0.15 .ohm.-cm, .mu.$_{n}$ .iden.500c $m^{2}$ $V^{-1}$ se $c^{-1}$ for n-type at 300K. In case of treatment with metal ion of R $u^{+3}$, P $t^{+4}$, the carrier concentration, resistivity and carrier mobility of the GaSb crystals were p.iden.2*10$^{17}$ c $m^{-3}$ , .rho..iden.0.08.ohm.-cm, .mu.$_{p}$ .iden.420c $m^{2}$ $V^{-1}$ se $c^{-1}$ for p-type, n.iden.2.5*10$^{17}$ c $m^{-3}$ , .rho..iden.0.07.ohm.-cm, .mu.$_{n}$ .iden.520c $m^{2}$ $V^{-1}$ se $c^{-1}$ for n-type respectively. GaSb crystals had a tendency to lower resistivity and higher mobility, for surface treatment with metal ion effectively diminished surface recombination centers.s.

• 한국재료학회지
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• 제14권1호
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• pp.41-45
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• 2004

P-type $Bi_{0.5}$$Sb_{1.5}$ $Te_3$ thin films were deposited by the flash evaporation technique, and their thermoelectric properties and electronic transport parameters were investigated. The effective mean free path model was adopted to examine the thickness effect on the thermoelectric properties. Annealing effects on the carrier concentration and mobility were also studied, and their variations were analyzed in conjunction with the antisite defects. Seebeck coefficient and electrical resistivity versus inverse thickness showed a linear relationship, and the effective mean free path was found to be 3150$\AA$. No phase transformation and composition change were observed after annealing treatment, but carrier mobility increased due to grain growth. Carrier concentration decreased considerably due to reduction of the antisite defects, so that electrical conductivity decreased and Seebeck coefficient increased. When annealed at 473 K for 1 hr, Seebeck coefficient and electrical conductivity were $160\mu$V/K and 610 $W^{-1}$ $cm^{ -1}$, respectively. Therefore, the thermoelectric quality factor were also enhanced to be $16\mu$W/cm $K^2$.>.