Browsing by Issue Date, starting with "1998-01-07"

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Elastic reflection of low-energy electrons from polycrystalline gold targets
(1998-01-07)
Kwei, CM
;
Chen, YF
;
Tung, CJ
;
電子工程學系及電子研究所
;
Department of Electronics Engineering and Institute of Electronics
Monte Carlo calculations to study the influence of solid-state, polarization, exchange and relativistic effects on the angular distribution and the reflection coefficient for electrons elastically reflected from gold surfaces have been performed. Elastic differential cross sections were determined using relativistic Dirac equations with a solid atom potential including the polarization and exchange effects. Inelastic differential inverse mean free paths were computed using the extended Drude dielectric function for volume and surface excitations. These showed that the polarization effect made a contribution to elastic differential cross sections at small scattering angles, whereas, the exchange and relativistic effects contributed to these cross sections at Barge scattering angles. These effects are important to the angular distribution and the elastic reflection coefficient for electron energies below 400 eV, Monte Carlo results calculated in this work are in very good agreement with experimental data.
Suppression of boron penetration in p(+) polysilicon gate using Si-B diffusion source
(1998-01-08)
Chao, TS
;
Kuo, CP
;
Lei, TF
;
Chen, TP
;
Huang, TY
The authors report a novel Si-B diffusion source for doping p(+)-poly-Si gates in pMOSFETs. It is found that B penetration can be effectively suppressed by using this novel process. AU of the electrical properties of the MOS capacitors are significantly improved over those in the conventional BF2+ or B+-implanted samples. This new process is very promising for future surface-channel pMOSFETs.
Investigation of silicon oxide films prepared by room-temperature ion plating
(1998-01-15)
Yeh, CF
;
Chen, TJ
;
Fan, CL
;
Kao, JS
;
電子工程學系及電子研究所
To develop excellent silicon oxide film using low temperature method, ion plating (IP) oxide is investigated. Physicochemical characterizations of the IP oxide are studied using ellipsometry, Fourier transform infrared spectrometry, and P-etch rate measurement. The IP oxide is a high-density dielectric with strained bonds. Electrical characterizations are also analyzed using capacitance-voltage and current-voltage techniques through metal-oxide-semiconductor capacitors. The IP oxide has a low leakage current, a high breakdown field, and low interface state density. In addition, IP oxide annealed in N-2 ambient is also studied. After high-temperature annealing, the characteristics of IP oxide become comparable to those of thermal oxide. The novel oxide him is successfully applied as a gate insulator to low-temperature processed (less than or equal to 620 degrees C) polysilicon thin-film transistors. (C) 1998 American Institute of Physics.
Self-assembly of alkylsiloxane monolayers on fused silica studied by XPS and sum frequency generation spectroscopy
(1998-01-15)
Lagutchev, AS
;
Song, KJ
;
Huang, JY
;
Yang, PK
;
Chuang, TJ
Infrared-visible sum frequency generation (SFG) vibrational spectroscopy in the C-H stretching region was used to study a set of self-assembled monolayers, formed from octyltrichlorosilane [CH3(CH2)(7)SiCl3], its partially fluorinated analog, (tridecafluoro-1,1,2,2-tetrahydrooctyl)-1-trichlorosilane [CF3-(CF2)(5)(CH2)(2)SiCl3] and their mixtures. SFG measurements were complemented with transmission-absorption FTIR spectroscopy and X-ray photoemission spectroscopy. Simultaneous self-assembly of both chlorosilanes results in preferential deposition of the fluorinated compound. The major reason for this behavior is the alkyl chain fluorination. There is a strong spectroscopic evidence of close coadsorption of fluorinated and non-fluorinated molecules in mixed monolayers. It follows that the species in self-assembled monolayers of binary composition do not segregate into different phases as it is observed for similar Langmuir-Blodgett films. Distinct differences found in SFG spectra of fluorinated and non-fluorinated samples indicate that SFG spectroscopy is much more sensitive than FTIR in detection of symmetry distortions in the alkyl chain of the amphiphiles. Both SFG and FTIR spectroscopic data show the presence of hydrocarbon residue in fluorinated and mixed films that is very likely due to hexadecane used as a solvent during monolayer deposition. (C) 1998 Elsevier Science B.V.
Dynamics of an optical resonator determined by its iterative map of beam parameters
(1998-01-15)
Wei, MD
;
Hsieh, WF
;
Sung, CC
;
光電工程學系
;
Department of Photonics
We use the residue of the map to study the stability and Gaussian beam dynamics of a general optical resonator. The map is constructed from space domain matrix formalism. For a lossless system we find that the residue is a function of resonator g-parameters' product and new critical stable curves exist within the geometrically stable regions. The dynamic behavior of a dissipative resonator with loss optical element is similar to a damping oscillatory motion and can be determined by the corresponding conservative resonator without those loss elements. (C) 1998 Elsevier Science B.V.
蟬
(1998-01-30)
管管
蟬
(1998-01-30)
管管
蟬
(1998-01-30)
管管
搖籃邊的低語
(1998-01-30)
管管
QTS: A QOS-guaranteed transport system for broad-band multimedia communications
(1998-02-01)
Yuang, MC
;
Liu, JC
;
資訊工程學系
;
Department of Computer Science
In this paper, we propose a quality of-service (QOS)guaranteed transport system (QTS), which offers various QOS's at the transport layer for broad-band multimedia communications, The QTS, composed of a bandwidth allocator and a transport protocol module, supports three classes of applications requiring different bit rates, delay sensitivity, and loss sensitivity, The bandwidth allocator intelligently manages the allocation of transport-layer bandwidth at the expense of imposing inevitable blocking of delay-sensitive application connections, The transport protocol module of the QTS performs rate-based flow control for delay-sensitive applications based on transfer rates predetermined by the bandwidth allocator, In addition, the module accomplishes error control only for loss-sensitive applications, As a result, as will be shown, by providing guaranteed rates and reducing the error control overhead, the QTS offers satisfactory bounded delays and jitters for delay-sensitive applications, while incurring minimal throughput degradation for loss-sensitive applications, Finally, we demonstrate the superiority of the QTS over transmission control protocol (TCP) via simulation results in terms of maximum and mean system delays and delay jitter.
Highly oriented (Zr0.7Sn0.3)TiO4 thin films grown by rf magnetron sputtering
(1998-02-01)
Wu, FJ
;
Tseng, TY
;
電子工程學系及電子研究所
;
Department of Electronics Engineering and Institute of Electronics
Thin films of (Zr0.7Sn0.3)TiO4 on Si(100) were prepared by rf magnetron sputtering in the present study. Films of a highly preferred [020] orientation, as demonstrated by X-ray diffraction and transmission electron microscopic examinations, were grown successfully on a Si substrate with in situ postannealing at 700 degrees C. The chemical composition of the films, measured by secondary ion mass spectroscopy, exhibited a uniform concentration distribution for all species. A study by X-ray photoelectron spectroscopy further revealed some firm evidence of a molecular orbital that affected the chemical structure. The dielectric constants of 400-nm-thick (Zr0.7Sn0.3)TiO4 films in the present study were >18 for the films with a preferred orientation and similar to 11 for polycrystalline films.
上聯:自古帝王多流氓下聯:從來英雄皆無賴橫批:為人民服務
(1998-02-01)
管管
QTS: A QOS-guaranteed transport system for broad-band multimedia communications
(1998-02-01)
Yuang, MC
;
Liu, JC
;
資訊工程學系
;
Department of Computer Science
In this paper, we propose a quality of-service (QOS)guaranteed transport system (QTS), which offers various QOS's at the transport layer for broad-band multimedia communications, The QTS, composed of a bandwidth allocator and a transport protocol module, supports three classes of applications requiring different bit rates, delay sensitivity, and loss sensitivity, The bandwidth allocator intelligently manages the allocation of transport-layer bandwidth at the expense of imposing inevitable blocking of delay-sensitive application connections, The transport protocol module of the QTS performs rate-based flow control for delay-sensitive applications based on transfer rates predetermined by the bandwidth allocator, In addition, the module accomplishes error control only for loss-sensitive applications, As a result, as will be shown, by providing guaranteed rates and reducing the error control overhead, the QTS offers satisfactory bounded delays and jitters for delay-sensitive applications, while incurring minimal throughput degradation for loss-sensitive applications, Finally, we demonstrate the superiority of the QTS over transmission control protocol (TCP) via simulation results in terms of maximum and mean system delays and delay jitter.
【臨床頻道】齒顎矯正治療時機
(國立陽明大學牙醫校友會, 1998-02)
馮懷珍
Real-time scanning tunneling microscopy observation of Si(100)-(2x1)->(2xn)-> c(4x4) structural phase transitions
(1998-02-01)
Lin, DS
;
Wu, PH
;
物理研究所
;
Institute of Physics
We report on the discovery of Si(100)-(2 x 1)-->(2 x n)-->c(4 x 4) structural phase transitions. Annealing the Si(100)-(2 x 1) surface between 590 and 700 degrees C for some hours causes dimer vacancies to increase and nucleate into chains, ultimately forming the (2 x n) structure. After further annealing. c(4 x 4) areas appear grow. and finally cover the entire surface. Experimental results raise the possibility not only that c(4 x 4) is a stable low-temperature structure of Si(100), but that (2 x 1) is a high-temperature phase stabilized at room temperature owing to its kinetic limitations. (C) 1998 Elsevier Science B.V.
專訪管管先生
(1998-02-01)
管管
Synthesis of carbon-chain tethered bistetraoxa-cage compounds
(1998-02-01)
Chern, JH
;
Wu, HJ
;
Wang, SL
;
Liao, FL
;
應用化學系
Carbon-chain tethered bistetraoxa-cage compounds 7a-c and 8a-c were synthesized from 2-methyl-furan in a four-step sequence. They were obtained from ozonolysis of the syn bisadducts 5a-c and the anti bisadducts 6a-c in dichloromethane at -78 degrees C followed by reduction with dimethyl sulfide. The structure of the anti bisadduct 6a was proven by X-ray crystallographical analysis.
【逍遙遊】蘭陽-新桃花之旅
(國立陽明大學牙醫校友會, 1998-02)
董醒任
High precision, low cost mask for deep x-ray lithography
(1998-02-01)
Shew, BY
;
Cheng, Y
;
Shih, WP
;
Lu, M
;
Lee, WH
The precision of transferred patterns are highly dependent on the quality of the mask in deep x-ray lithography. Many parameters, such as the critical energy of the synchrotron light, beamline optics and even the microstructure to be exposed should be considered in mask design. In this paper, the design rules and the boundary conditions for deep x-ray mask are discussed in general. The method of making a precision, multilayer mask using UV lithography technique is also described.
Photoluminescence studies of GaN films of different buffer layer and doping concentration
(1998-02-01)
Shen, CC
;
Shu, CK
;
Lin, HC
;
Ou, J
;
Chen, WK
Photoluminescence (PL) measurements of GaN films with various buffer thicknesses and Si-doping concentrations have been carried out. PL response of one specific sample was studied for temperature dependence. The results showed that the band gap energy reduction is linearly proportional to the temperature increase with a slope of similar to-4 x 10(-4) eV.K-1 and that the activation energies for donor-bound and acceptor-bound exciton transitions are 15 and 18 meV, respectively. In Si-doped GaN films, the PL data indicated that the reduced gap depends on the third power of carrier concentration as n(1/3). We also obtained a concentration coefficient of 2.34 x 10(-4) eV.cm and a band gap energy of 3.426 eV in the undoped GaN film.