Browsing by Author "Lin, KC"

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Analysis of a liquid crystal Fabry-Perot etalon filter: A novel model
(1997-04-01)
Chen, PL
;
Lin, KC
;
Chuang, WC
;
Tzeng, YC
;
Lee, KY
The authors propose a novel analysis method to investigate the characteristics of an electrically tunable liquid-crystal Fabry-Perot interferometer (LC-FPI), Based on the solution of deformation analysis of liquid crystal in an electric field and the assumption of small refractive index variation in the Fabry-Perot cavity, the voltage-dependent equivalent refractive index of the cavity has been derived. Tuning behaviors of the LC-FPI filter were simulated by means of the dependence, The calculated result and the experimental measured data agree well with each other.
Analysis of a liquid crystal Fabry-Perot etalon filter: A novel model
(1997-04-01)
Chen, PL
;
Lin, KC
;
Chuang, WC
;
Tzeng, YC
;
Lee, KY
The authors propose a novel analysis method to investigate the characteristics of an electrically tunable liquid-crystal Fabry-Perot interferometer (LC-FPI), Based on the solution of deformation analysis of liquid crystal in an electric field and the assumption of small refractive index variation in the Fabry-Perot cavity, the voltage-dependent equivalent refractive index of the cavity has been derived. Tuning behaviors of the LC-FPI filter were simulated by means of the dependence, The calculated result and the experimental measured data agree well with each other.
Anderson model with spin-flip-associated tunneling
(2005-09-01)
Lin, KC
;
Chuu, DS
;
電子物理學系
;
Department of Electrophysics
The spin-flip-associated transport through a quantum dot based on the Anderson model in equilibrium and nonequilibrium situations is studied. It is found that electrons are scattered due to the spin-flip effect via the normal and the Kondo channels. Our results show that the conductance is suppressed due to the spin-flip effect, and the suppression due to the spin-flip scattering via the Kondo channel is stronger for temperatures below the Kondo temperature.
Ballistic transport through coupled T-shaped quantum wires
(2004-05-01)
Lin, YK
;
Lin, KC
;
Chuu, DS
;
電子物理學系
;
Department of Electrophysics
The ballistic conductance of a coupled T-shaped semiconductor quantum wire (CTQW) is studied. Two types of CTQW are considered, one of which is a H-shaped quantum wire (PiQW) which consists of two vertical arms on the same side of the horizontal arm and the other a Pi-clone quantum wire (PiCQW) which consists of two vertical armes on the opposite sides of the horizontal arm. The mode matching method and Landauer-Buttiker theory are employed to study the energy dependence of the ballistic conductance. Most of transmission profiles of PiQW and PiCQW are found to be distinguishable for large separation d between the two vertical arms. The transmission probability manifests oscillatory behavior when d is increased. When a potential is applied to the connection region, it results in decoupling or coupling effects between the two T-shaped quantum wires according to whether it is positive or negative. When magnetic field is applied to CTQW, the transmission profiles are found to be affected prominently even if the electron passes through the field free region only. (C) 2003 Elsevier B.V. All rights reserved.
Characterization of additive systems for damascene Cu electroplating by the superfilling profile monitor
(2000-11-01)
Chiu, SY
;
Shieh, JM
;
Chang, SC
;
Lin, KC
;
Dai, BT
Gap-filling dynamics of several different species of additives for copper electrodeposition was investigated by monitoring the cross section of a partially filled copper profile on the scanning electron microscopy photo. The filling ration Deltay/Deltax between "bottom-up" with "sidewall shift" was found to be proportional to the filing power of additives. The adsorption-diffusion model combined with cathode polarization and cyclic voltammetric stripping measurements was employed to explain the attribution of additives in superfilling phenomena. The superfilling dynamics was achieved under behavior of additives providing selective inhibition gradient within the damascene feature. By means of those analyses, we have optimized the appropriate amount of additives and achieved the superfilling performance for 0.15 mum vias with aspect ratio 6 by an acid-copper electrolyte with polyethylene glycol, Cl-, and 2-mercaptopyridine (2-MP). Due to the additive of 2-MP, chelate formed which enhanced adsorption ability on Cu-0 surface, and the concentration gradient between side-wall shift and bottom-up in the damascene became high enough to attend superfilling electroplating. (C) 2000 American Vacuum Society. [S0734-211X(00)13506-1].
Comparison of the relative toxicity relationships based on batch and continuous algal toxicity tests
(1997-11-01)
Chen, CY
;
Lin, KC
;
Yang, DT
;
交大名義發表
;
環境工程研究所
In this study, we compare individual and combined responses of metal toxicants, on Selenastrum capricornutum, using batch and continuous techniques. The batch test is characterized by its saturated nutrient status for algal growth and, on the other hand, the continuous test is conducted at a nutrient-limiting condition. The two test methods depict completely different relationships in relative toxicity. In addition, the batch tests seriously underestimate the toxicity of metal mixtures containing lead. The above phenomena can be attributed to the surplus amounts of a limiting nutrient (phosphorus) and chelators in the growth medium. Since algae in the field are grown under low concentrations of nutrients and chelators, the results presented herein suggest that the significance and adequacy of current algal toxicity test protocols should be carefully reviewed. (C) 1997 Elsevier Science Ltd.
Computation of unstable liquid metal convection in a vertical closed cylinder heated from the side and cooled from above
(1997-08-29)
Li, YH
;
Lin, KC
;
Lin, TF
;
機械工程學系
;
Department of Mechanical Engineering
Three-dimensional unsteady numerical computation was carried out to investigate buoyancy-driven unstable convection processes in a side-wad-heated and top-wad-cooled vertical closed cylinder containing liquid metal. The time-dependent basic flow equations were directly solved by the implicit Marker-and-Cell (MAC) scheme with the power law approximation to treat the convection-diffusion couplings. Results were obtained for liquid metal (Pr = 0.02) in a cylinder of finite aspect ratio (Gamma = 2) for various Rayleigh numbers. The predicted results indicate that the flow is relatively unstable except at low buoyancy. Specifically, of Ra = 2000 the flow evolves to a steady state but is highly asymmetric. As Ra = 3000 and 4000, the flow Becomes time periodic after the transient has died out with increasing asymmetry. At a still higher buoyancy the oscillation amplitude and flow asymmetry get larger, and a second fundamental frequency appears. The flow is quasi-periodic. Qualitatively, the flow structure is characterized by a main recirculation ill the major portion of the cylinder along with two uprising smaller cells near the side wall in the bottom half of the cylinder and another two counter rotating cells in the top half of the cylinder Finally, the critical Rayleigh number for the transition from a steady to a time periodic state was evaluated.
Computation of unstable liquid metal convection in a vertical closed cylinder heated from the side and cooled from above
(1997-08-29)
Li, YH
;
Lin, KC
;
Lin, TF
;
機械工程學系
;
Department of Mechanical Engineering
Three-dimensional unsteady numerical computation was carried out to investigate buoyancy-driven unstable convection processes in a side-wad-heated and top-wad-cooled vertical closed cylinder containing liquid metal. The time-dependent basic flow equations were directly solved by the implicit Marker-and-Cell (MAC) scheme with the power law approximation to treat the convection-diffusion couplings. Results were obtained for liquid metal (Pr = 0.02) in a cylinder of finite aspect ratio (Gamma = 2) for various Rayleigh numbers. The predicted results indicate that the flow is relatively unstable except at low buoyancy. Specifically, of Ra = 2000 the flow evolves to a steady state but is highly asymmetric. As Ra = 3000 and 4000, the flow Becomes time periodic after the transient has died out with increasing asymmetry. At a still higher buoyancy the oscillation amplitude and flow asymmetry get larger, and a second fundamental frequency appears. The flow is quasi-periodic. Qualitatively, the flow structure is characterized by a main recirculation ill the major portion of the cylinder along with two uprising smaller cells near the side wall in the bottom half of the cylinder and another two counter rotating cells in the top half of the cylinder Finally, the critical Rayleigh number for the transition from a steady to a time periodic state was evaluated.
Dual-bandpass filters with serial configuration using LTCC technology
(2006-06-01)
Lin, KC
;
Chang, CF
;
Wu, MC
;
Chung, SJ
;
電信工程研究所
A dual-bandpass filter that utilizes a serial configuration of the inductive coupled-line (ICL) filter and the capacitive coupled-line (CCL) filter is investigated in this study. Numerical analysis is presented for the difference between the ICL and CCL filters. The dual-bandpass filter has a similar behavior to the individual single-band filter around the corresponding passband. An extra transmission zero can be generated between the two pass-bands of the dual-bandpass filter in that the ICL and CCL filters exhibit an out-of-phase response. Four architectures of dual-bandpass filters are proposed for the 2.4/5-GHz systems. Two of them are demonstrated by the low-temperature co-fired ceramic multilayer technology. Measurements results agree quite well with the simulation ones.
Effect of deposited particles and particle charge on the penetration of small sampling cyclones
(1999-03-01)
Tsai, CJ
;
Shiau, HG
;
Lin, KC
;
Shih, TS
;
環境工程研究所
Effects of particle mass deposited in the cyclone and particle electrostatic charge on the particle penetration of the commonly used 10mm nylon cyclone have been experimentally investigated in this study. The solid particle penetration of the cyclone has been found to decrease with an increase in particle mass deposited in the cyclone. This effect is most significant for particles near the cutoff aerodynamic diameter and when the deposited particle mass is low. The penetration of the cyclone has also been found to be influenced by particle electrostatic charge. This effect is also significant for particles near the cutoff aerodynamic diameter and when the number of elementary units of charge is greater than several thousands. To overcome these problems, a new cyclone made of conductive aluminum and with inner diameter nearly twice that of the 10 mm nylon cyclone has been designed and tested. Experimental results indicate that effects of both deposited particle mass as well as electrostatic charge on the penetration are reduced substantially in this cyclone. (C) 1999 Elsevier Science Ltd. All rights reserved.
Effect of pulse frequency on leveling and resistivity of copper coatings
(2002-05-01)
Chen, CF
;
Lin, KC
;
材料科學與工程學系
;
Department of Materials Science and Engineering
Pulse-and DC-plated copper films on wafers were investigated with respect to their applicability as advanced interconnect materials. Pulse frequency was varied to determine its influence on the topography, grain size, and electrical resistivity of electroplated copper films. Morphology and scanning electron microscopy (SEM) studies were conducted on these samples. Smooth and dense coatings were obtained at the optimal frequency of 100 Hz, which displayed the smallest electrical resistance. The leveling capacity of submicron features was also optimized at this frequency.
Effects of gamma radiation on optical fibre sensors
(2004-02-01)
Lin, KC
;
Lin, CJ
;
Lee, WY
;
光電工程學系
;
Department of Photonics
Consideration of thermo-optic coefficients is essential in the applications of optical fibre sensors and high-speed fibre communication systems. The Fabry-Perot interference method is applied to study these coefficients of four types of commercial fibres. The results are in agreement with the values calculated from the Sellmeier equation for fused silica fibre, with a difference of only about 0.2% for the Coming single-mode fibre SMF-28. In order to apply fibre sensors to a high-radiation environment, the thermo-optic coefficients for these fibres have been investigated after exposure to heavy doses of gamma radiation, and their radiation resistance has been studied.
Effects of the relationship between resistivity and additive chemistries in electrochemically deposited copper films
(2002-04-01)
Chen, CF
;
Lin, KC
;
材料科學與工程學系
;
Department of Materials Science and Engineering
The room-temperature electrical resistance of copper films on silicon wafers deposited from acid-copper sulfuric solutions is a function of grain size and impurity content. These properties were examined by a series of additive chemistries used in plating baths. The trapped impurities and the functional characteristics of additives were analyzed by X-ray photoelectron spectroscopy (XPS) and cyclic voltammetric stripping (CVS) measurements, The impurity scattering effect on the resistances depends on the charge factor for different dopants. On the other hand, the effect of grain-boundary scattering on the resistances will depend on the extent of activation overpotential of various additive chemistries. Evidence suggests that additive chemistries with a higher overpotential would create a higher resistivity due to larger grain-boundary scattering and greater impurity incorporation into copper films.
Electromigration studies of flip chip Sn95/Sb5 solder bumps on Cr/Cr-Cu/Cu under-bump metallization
(2003-11-01)
Shao, TL
;
Lin, KC
;
Chen, C
;
材料科學與工程學系
;
Department of Materials Science and Engineering
The electromigration-induced failure of Sn95/Sb5 flip chip solder bumps was investigated. The failure of the joints was found at the cathode/chip side after current stressing with a density of 1 X 10(4) A/cm(2) at 150degreesC for 13 sec. The growth of intermetallic compounds (IMCs) was observed at the anode side after current stressing. Voids were found near the current crowding area in the cathode/chip side, and the (Cu,Ni)(6)Sn-5 IMC at the cathode/chip end was transformed into the Sn phase. The failure mechanism for Sn95/Sb5 flip chip solder joint is proposed in this paper.
Electroplating copper in sub-100 nm gaps by additives with low consumption and diffusion ability
(2002-05-01)
Lin, KC
;
Shieh, JM
;
Chang, SC
;
Dai, BT
;
Chen, CF
This work presents a novel leveler with low consumption and low diffusion that achieved defect-free filling in vias as small as 0.1 mum and generated as-deposited films with low resistivities. Experimental results indicate that the additive, 2-aminobenzothiazole (2-ABT), with benzyl and amino (-NH2) functional groups, is a desirable leveler. It produced a highly selective concentration gradient between the opening and the bottom of the feature. This novel leveler, with weaker adsorption, also reduced the consumption during copper electroplating, and eventually deposited a film with a high conductivity. (C) 2002 American Vacuum Society.
Improved field-emission properties of carbon nanotube field-emission arrays by controlled density growth,of carbon nanotubes
(2005-01-01)
Juan, CP
;
Chen, KJ
;
Tsai, CC
;
Lin, KC
;
Hong, WK
The density distribution of CNTs is one of the. crucial parameters determing the field-emission property of CNTs. To effectively control the density of CNTs, an inactive thin-film layer was deposited on a catalyst. The results showed that improved field emission property could be obtained with a thin SiO layer on the catalyst layer as the precursor. For 3.5 nm Fe and 3.5 nm SiO on 3.5 nm Fe as a catalyst, the turn-on field could be decreased from 3.7 V/mum. to 2.2 V/mum and the field-emission current density increased from 2.6 x 10(-8) A/cm(2) to 2.4 x 10(-4) A/cm(2) when the applied field was 4 V/mum.
Investigations of effects of bias polarization and chemical parameters on morphology and filling capability of 130 nm damascene electroplated copper
(2001-05-01)
Chang, SC
;
Shieh, JM
;
Lin, KC
;
Dai, BT
;
Wang, TC
Through elucidating the effects of current density, cupric ion concentration, bath temperature, and air agitation on plating uniformity and filling capability of copper electroplating, the deposition of copper in an acid copper electrolyte will be illustrated to scale down to the sub-0.13 mum features with uniform plating, which is required by chemical mechanical polishing in current damascene techniques. In order to achieve the defect-free filling in sub-0.13 mum vias and trenches, the electrolyte must be composed of proper amounts of cupric ions, sulfuric acid, chloride ions, wetting agent, and filling promoter. The supplied current controlled at a lower current density, agitation acceded to the electroplating process were found as further keys. In the electrolyte, the filling promoter was consisted essentially of thiazole derivatives with benzyl groups and amino-group (-NH2) offering sufficient inhibition on copper depositing and selective inhibition gradient. Moreover, a lower resistivity film and higher filling capability could be obtained by using periodic pulse current plating as compared with direct current plating. (C) 2001 American Vacuum Society.
Leveling effects of copper electrolytes with hybrid-mode additives
(2002-11-01)
Lin, KC
;
Shieh, JM
;
Chang, SC
;
Dai, BT
;
Chen, CF
100 nm vias were completely filled with copper for interconnect applications using an electrolyte in the presence of polyethylene glycols (PEG) and a hybrid-mode additive, benzotriazole (BTA). Electrochemical analyses indicated that BTA with a higher concentration inhibited the copper deposition rate, whereas BTA with a lower concentration accelerated the copper deposition rate. This electrolyte thus generated an enhanced deposition gradient within a gap because the PEG molecules and the high concentration of BTA, adsorbed at the opening of the gap, inhibited the deposition. Meanwhile, a little BTA diffused into the inner part of the gap and thus accelerated the deposition of copper. Therefore, this two-component (PEG and BTA) additive electrolyte had the capacity of a three-additive bath (accelerators, suppressors, and levelers). (C) 2002 American Vacuum Society.
Measurement of electrically tunable liquid-crystal Fabry-Perot interferometer using a monochromatic light source
(1999-07-05)
Lin, KC
;
Lin, JS
;
Chen, PL
;
Chuang, WC
;
光電工程學系
We propose a novel technique to characterize an electrically tunable liquid-crystal Fabry-Perot interferometer. Only one usual set of a monochromatic light source and an optical power meter is needed. Various characteristic parameters were estimated based on the equivalent refractive index analysis and the measured voltage-dependent transmittance. (C) 1999 John Wiley & Sons, Inc.
Optimization and performance evaluation of the continuous algal toxicity test
(1997-07-01)
Chen, CY
;
Lin, KC
;
環境工程研究所
;
Institute of Environmental Engineering
Responses of Selenastrum capricornutum to cadmium in a chemostat are evaluated under various test conditions defined by the nitrogen to phosphorus ratio, phosphate strength, dilution rate, and ethylenediaminetetraacetic acid content. Based on the test results, these parameters were optimized to achieve superior test sensitivity. This continuous system was also modified to allow testing on a weekly basis. The performance of the modified testing technique was evaluated, employing six different metal toxicants. Compared with batch test results reported by other researchers and our own experiment, the continuous test achieved superior sensitivities and reproducibility. The test method presented in this study is believed to be an ideal technique both for research and regulatory purposes.