• Title/Summary/Keyword: Electron Flow

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Structural and discharge characteristics of MgO films prepared by Arc Ion Plating (AIP) method

  • Kim, Jong-Kuk;Kim, Do-Geun;Lee, Eun-Sung;Lee, Sung-Hun;Lee, Gun-Hwan
    • 한국정보디스플레이학회:학술대회논문집
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    • 2002.08a
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    • pp.625-627
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    • 2002
  • MgO thin films were deposited on glass and (100) Si substrates by an Arc Ion Plating (AIP) equipment using a magnesium metal target at various oxygen gas flow. In this work, we investigated the relationship between the structural properties and the discharge characteristics of MgO coating layers. X-ray diffraction and AFM have been used to study behaviors of the structure and surface morphology. The optical transmittance and the ion induced secondary electron emission coefficient of the MgO films have been also measured. The resistivity of the deposited MgO films was gradually increased from 0.17 G ohm/${\square}$ to 0.35 G ohm/${\square}$ with the oxygen gas flow. The growth rate of the MgO coating layer was decreased with increasing the oxygen gas flow, while the optical transmittance was improved.

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Characterization of 3C-SiC grown on Si(100) water (Si(100) 기판상에 성장된 3C-SiC의 특성)

  • Na, Kyung-Il;Chung, Yun-Sik;Ryu, Ji-Goo;Chung, Gwiy-Sang
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2001.11b
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    • pp.533-536
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    • 2001
  • Single crystal cubic silicon carbide(3C-SiC) thin film were deposited on Si(100) substrate up to a thickness of $4.3{\mu}m$ by APCVD(atmospheric pressure chemical vapor deposition) method using hexamethyildisilane(HMDS) at $1350^{\circ}C$. The HMDS flow rate was 0.5 sccm and the carrier gas flow rate was 2.5 slm. The HMDS flow rate was important to get a mirror-like. The growth rate of the 3C-SiC films was $4.3{\mu}m/hr$. The 3C-SiC epitaxical layers on Si(100) were characterized by XRD(X-ray diffraction), raman scattering and RHEED(reflection high-energy electron diffraction), respectively. The 3C-SiC distinct phonons of TO(transverse optical) near $796cm^{-1}$ and LO(longitudinal optical) near $974{\pm}1cm^{-1}$ were recorded by raman scattering measurement. The deposition films were identified as the single crystal 3C-SiC phase by XRD spectra($2{\theta}=41.5^{\circ}$). Also, with increase of films thickness, RHEED patterns gradually changed from a spot pattern to a streak pattern.

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A Study on the Optical Emission Spectroscopy of the RF Inductive Plasma Process (RF 유도형 플라즈마 프로세스에 대한 분광학적 연구)

  • Jang, Mun-Gug;Han, Sang-Bo;Park, Sang-Hyun
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.25 no.11
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    • pp.103-112
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    • 2011
  • This paper is tried to analysis the optical emission spectroscopy related to the position of inductive load coil and flow rates of methane and oxygen in the RF inductive plasma process. According to the position of load coil, peak of $H_{\alpha}$, $H_{\beta}$, and CH were appeared strongly at the middle position of the coil and it decreased both direction. The electron temperature was approximately 0.9[eV] at that position. Emission intensities of $H_{\alpha}$, $H_{\beta}$, and CH increased linearly by increasing input power. In addition, intensities of $H_{\alpha}$ and $H_{\beta}$ increased by increasing the flow rate of oxygen. It might be ascribed that the oxygen species were bonded with $C_nH_m$ by suppressing the combination with hydrogen atoms. Consequently, the optimal position of the inductive coil is decided to the intermediate position between 4th and 5th turns, the wanted carbon thin-film is possible to deposit by controlling flow rates of methane and oxygen.

Characterization of 3C-SiC grown on Si(100) wafer (Si(100) 기판상에 성장된 3C-SiC의 특성)

  • 나경일;정연식;류지구;정귀상
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2001.11a
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    • pp.533-536
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    • 2001
  • Single crystal cubic silicon carbide(3C-SiC) thin film were deposited on Si(100) substrate up to a thickness of 4.3 $\mu\textrm{m}$ by APCVD(atmospheric pressure chemical vapor deposition) method using hexamethyildisilane(HMDS) at 1350$^{\circ}C$. The HMDS flow rate was 0.5 sccm and the carrier gas flow rate was 2.5 slm. The HMDS flow rate was important to get a mirror-like. The growth rate of the 3C-SiC films was 4.3 $\mu\textrm{m}$/hr. The 3C-SiC epitaxical layers on Si(100) were characterized by XRD(X-ray diffraction), raman scattering and RHEED(reflection high-energy electron diffraction), respectively The 3C-SiC distinct phonons of TO(transverse optical) near 796 cm$\^$-1/ and LO(longitudinal optical) near 974${\pm}$1 cm$\^$-1/ were recorded by raman scattering measurement. The deposition films were identified as the single crystal 3C-SiC phase by XRD spectra(2$\theta$=41.5$^{\circ}$). Also, with increase of films thickness, RHEED patterns gradually changed from a spot pattern to a streak pattern

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A Study on the Silicon Etching Characteristics in ECR using ${SF_6}/{Cl_2}$ Gas Mixtures (${SF_6}/{Cl_2}$ 혼합비에 따른 실리콘 식각 특성 고찰)

  • 이상균;강승열;권광호;이진호;조경익;이형종
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.13 no.2
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    • pp.114-119
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    • 2000
  • Etch characteristics of SF6/CI2 electron cyclotron resonance (ECR) plasmas have been investigated. Surface reaction of gas plasma with polysilicon was also analysed using X-ray photoelectron spectroscopy (XPS). At the same time, the relationship between surface reaction and the etched profile of polysilicon was examined using XPS. The etch rate of polysilicon and oxide increases with increasing flow rate of SF6 in the SF6/CI2 gas mixture, and tis selectivity also increase also increase. It was also found that as increasing flow rate of SF6 in the SF6/CI2 gas mixture, the atomic% of chlorine detected at surface region decrease, but F and S contents increase. At the same time, when the mixing ratio of SF6 gas increases, the anisotropy of etched polysilicon is sharply decreased in the 0%~10% range of the SF6 mixing ratio, but is rarely varied in the range over 10%, in spite of the large variations in flow rates. It can be explained that the bonding of S-Si due to SiSx(x$\leq$2) compound formed on the etched surface suppress the formation of Si-Cl and 'or Si-F bonding in the silicon etching.

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Electro-migration Phenomenon in Flip-chip Packages (플립칩 패키지에서의 일렉트로마이그레이션 현상)

  • Lee, Ki-Ju;Kim, Keun-Soo;Suganuma, Katsuaki
    • Journal of the Microelectronics and Packaging Society
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    • v.17 no.4
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    • pp.11-17
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    • 2010
  • The electromigration phenomenon in lead-free flip-chip solder joint has been one of the serious problems. To understand the mechanism of this phenomenon, the crystallographic orientation of Sn grain in the Sn-Ag-Cu solder bump has been analyzed. Different time to failure and different microstructural changes were observed in the all test vehicle and bumps, respectively. Fast failure and serious dissolution of Cu electrode was observed when the c-axis of Sn grain parallel to electron flow. On the contrary of this, slight microstructural changes were observed when the c-axis of Sn perpendicular to electron flow. In addition, underfill could enhance the electromigration reliability to prevent the deformation of solder bump during EM test.

Anti-tumor Effects and Apoptosis Induction by Realgar Bioleaching Solution in Sarcoma-180 Cells in Vitro and Transplanted Tumors in Mice in Vivo

  • Xie, Qin-Jian;Cao, Xin-Li;Bai, Lu;Wu, Zheng-Rong;Ma, Ying-Ping;Li, Hong-Yu
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.6
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    • pp.2883-2888
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    • 2014
  • Background: Realgar which contains arsenic components has been used in traditional Chinese medicine (TCM) as an anticancer drug. However, neither Realgar nor its formula are soluble in water. As a result, high dose of Realgar has to be administered to achieve an effective blood medicine concentration, and this is associated with adverse side effects. The objective of the present study was to increase the solubility of a formula using hydrometallurgy technology as well as investigating its effects on in vitro and in vivo cell proliferation and apoptosis in Sarcoma-180 cell line. Materials and Methods: Antiproliferative activity of Realgar Bioleaching Solution (RBS) was evaluated by MTT assay. Further, effects of RBS on cell proliferation and apoptosis were studied using flow cytometry and transmission electron microscopy. Kunming mice were administered RBS in vivo, where arsenic specifically targeted solid tumors. Results: The results indicated that RBS extract potently inhibited the tumor growth of Sarcoma-180 cell line in a dose-dependent manner. Flow cytometry and transmission electron microscopy further indicated that RBS significantly induced cell apoptosis through the inhibition of cell cycle pathway in a dose-dependent manner. Further, on RBS administration to mice, arsenic was specifically targeted to solid tumor.s Conclusions: RBS could substitute for traditional Realgar or its formula to work as a potent tool in cancer treatment.

Preparation, Characterization and Gas Permeability of Asymmetric Porous Membranes of Poly(carbobenzoxyl-L-Lysin) (비대칭 다공성 폴리(카르보벤족시-L-리신)막의 제조, 평가 및 기체투과)

  • Kawai, Tohru;Lee, Young Moo;Fujita, Hiroshi
    • Membrane Journal
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    • v.6 no.2
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    • pp.96-100
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    • 1996
  • In order to improve the permeability of the homogenous membrane of poly(carbobenzoxy-L-lysin)(PCLL), which has very high selectivity of helium gas to nitrogen gas, asymmetric porous membranes of PCLL were prepared by casting from 20% solutions in dioxane and dimethylformamide(DMF), respectively. The membranes were characterized by measuring the number of the pores, the pore size distribution of the surface(the skin layer) and the thickness of the skin layer by scanning electron microscope and transmission electron microscope. The mean pore size and the pore density were lower for the membrane cast from dioxane than that from DMF, which was explained by the mechanism of the formation of the pores in the asymmetric porous membrane. The permeability coefficient observed could be roughly explained by the viscous flow through the skin layer. However, the selectivity observed was against the theory of the viscous flow.

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Fabrication of Hot Electron Based Photovoltaic Systems using Metal-semiconductor Schottky Diode

  • Lee, Young-Keun;Jung, Chan-Ho;Park, Jong-Hyurk;Park, Jeong-Young
    • Proceedings of the Korean Vacuum Society Conference
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    • 2010.08a
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    • pp.305-305
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    • 2010
  • It is known that a pulse of electrons of high kinetic energy (1-3 eV) in metals can be generated with the deposition of external energy to the surface such as in the absorption of light or in exothermic chemical processes. These energetic electrons are not in thermal equilibrium with the metal atoms and are called "hot electrons" The concept of photon energy conversion to hot electron flow was suggested by Eric McFarland and Tang who directly measured the photocurrent on gold thin film of metal-semiconductor ($TiO_2$) Schottky diodes [1]. In order to utilize this scheme, we have fabricated metal-semiconductor Schottky diodes that are made of Pt or Au as a metallic layer, Si or $TiO_2$ as a semiconducting substrate. The Pt/$TiO_2$ and Pt/Si Schottky diodes are made by PECVD (Plasma Enhanced Chemical Vapor Deposition) for $SiO_2$, magnetron sputtering process for $TiO_2$, e-beam evaporation for metallic layers. Metal shadow mask is made for device alignment in device fabrication process. We measured photocurrent on Pt/n-Si diodes under AM1.5G. The incident photon to current conversion efficiency (IPCE) at different wavelengths was measured on the diodes. We also show that the steady-state flow of hot electrons generated from photon absorption can be directly probed with $Pt/TiO_2$ Schottky diodes [2]. We will discuss possible approaches to improve the efficiency of photon energy conversion.

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Ultrastructural characteristics of the pancreatic acinar cells in the diabetes-prone BB rat (BB랫드의 췌장 샘포세포의 미세구조적 특징)

  • Jeong, Young-gil;Kim, Kil-soo;Lee, Chul-ho;Won, Moo-ho;Cho, Sung-whan;Kim, Moo-kang
    • Korean Journal of Veterinary Research
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    • v.36 no.1
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    • pp.1-9
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    • 1996
  • Functional and morphological characteristics of the exocrine pancreas in genetic model BB rat of insulin dependent diabetes medllitus(IDDM) were carried out. Wistar rat was used as control animal. Flow rate of pancreatic juice, output of amylase and protein, and plasma glucose and insulin levess were examined. Also light and ultrastructural characteristics of the exocrine pancreas were observed. Pancreatic flow rate, output of amylase and protein, and insulin level were lower;glucose level was higher comparing with those of the control Wistar rat. In Wistar rat, exocrine pancreas was typical light microscopically. Zymogen granules and cell organelles were well developed in fine structure. Cell size of the periinsular acini was larger, and number of zymogen granules were more than those of the teleinsular acini. Most acinar cells were dark cells which containe well-developed RER in their cytoplasm. On the other hand, some light cells which have the dilated RER cisterns were found. In BB rat exocrine pancreas, cell size of per-and tele-insular acini similar to that of Wistar rat. The number of light cells occupied 40-50% compairing with that of Wistar rat. Zymogen granules were lower in number than that of Wistar rat and divied into three types in morphological characteristics ; type I showing normal structure, type II showing the wide hallo and small electron dense core in center of the zymogen granule and type III not having the electron dense core in the zymogen granule. The present ratio of type I, type II and type III are less than 5%, 30-40% and more than 50%, respectively.

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