Browsing by Issue Date, starting with "1994-03-15"

Now showing 1 - 20 of 88375

THE ENHANCEMENT OF OPTICAL 3RD HARMONIC SUSCEPTIBILITY IN A PARABOLIC QUANTUM-WELL BY TRIPLE-RESONANCE
(1994-03-15)
HUANG, YM
;
LIEN, CS
;
電子工程學系及電子研究所
;
Department of Electronics Engineering and Institute of Electronics
The third harmonic susceptibility for the finite parabolic quantum well (PQW) is studied theoretically. An important feature of the finite PQW is that the subband eigenenergies E(n) form an equally spaced energy-level ladder. Since the eigenenergy spacing hBARomega0 can be designed to resonate with the pumping source, the third harmonic susceptibility can be greatly enhanced through the triple resonance' A third harmonic susceptibility as high as 2000 (mm/V)2 could be achieved for the finite parabolic quantum well structure. This is a more than six orders of magnitude enhancement as compared to that of the bulk GaAs.
CAPACITIVELY COUPLED SI STRIP DETECTORS ON A 100 MM WAFER
(1994-03-15)
YEH, SC
;
SU, S
;
LU, JP
;
電子工程學系及電子研究所
;
Department of Electronics Engineering and Institute of Electronics
Silicon strip detectors with single-sided readout were designed and processed on 100 mm silicon wafers. Detectors with integrated coupling capacitors and polysilicon bias resistors were tested by electrical measurements. A 200 nm gate oxide thickness was chosen to provide a coupling capacitance of 9.75 pF/cm. A full depletion voltage of 80 V and leakage currents of 0.29, 0.64, 0.97, and 1.01 nA/strip for strip lengths of 2, 5, 7, and 8 cm, respectively were measured.
ORGANOMETALLIC VAPOR-PHASE EPITAXIAL-GROWTH OF ALASXSB1-X FILMS USING TERTIARYBUTYLARSINE
(1994-03-15)
CHEN, WK
;
OU, J
;
LEE, WI
;
交大名義發表
;
電子物理學系
The deposition of AlAsxSb1-x films is studied systematically using an organometallic vapor phase epitaxy growth technique. It is found that the growth of AlAsSb films requires a low V/III ratio to enhance the incorporation of antimony into the solid. The composition of the alloy also depends strongly on the growth temperature. Experimental data shows that films grown at higher temperatures yield much higher AlSb contents in the AlAsxSb1-x alloys. This is contrary to the results reported for GaAsSb films. In our study, we are able to grow metastable AlAsxSb1-x epitaxial films throughout the entire range of the solid composition for temperatures above 550-degrees-C.
FEMTOSECOND SOLITON PROPAGATION IN ERBIUM-DOPED FIBER AMPLIFIERS - THE EQUIVALENCE OF 2 DIFFERENT MODELS
(1994-03-15)
CHI, S
;
CHANG, CW
;
WEN, S
;
光電工程學系
;
Department of Photonics
The femtosecond soliton propagation in erbium-doped fiber amplifiers (EDFA) was calculated by using the coupled Maxwell-Bloch equations and the modified nonlinear Schrodinger equation with a complex lorentzian pin profile, respectively. Two results are found to be almost identical for the practical parameters of the EDFA. Therefore, accurate results can be obtained using the complex lorentzian gain profile, and it is much more time saving.
CONFIGURATION TRANSITION OF A CLOSED-CYLINDER NEMATIC LIQUID-CRYSTAL IN AN EXTERNAL ELECTRIC-FIELD
(1994-03-15)
CHEN, SH
;
WEI, JG
;
交大名義發表
;
光電工程學系
;
National Chiao Tung University
This study reports on the director-field configurations of a closed-cylinder nematic liquid crystal with negative dielectric anisotropy in an external electric field. Raising the applied voltage causes the director orientation with a volume point defect to be transformed from a normal to a twisted configuration. The voltage at which the configuration is transformed depends on the aspect ratio of the cylinder.
ON PRIME LABELINGS
(1994-03-15)
FU, HL
;
HUANG, KC
;
應用數學系
;
Department of Applied Mathematics
Let G = (V, E) be a graph. A bijection f:V--> {1, 2,...,V} is called a prime labelling if for each e = {u, v} in E, we have GCD(f(u),f(v)) = 1. A graph admits a prime labelling is called a prime graph. Around ten years ago, Roger Entringer conjectured that every tree is prime. So far, this conjecture is still unsolved. In this paper, we show that the conjecture is true for trees of order up to 15, and also show that a few other classes of graphs are prime.
STRONG ACCUMULATION OF AS PRECIPITATES IN LOW-TEMPERATURE INGAAS QUANTUM-WELLS GROWN BY MOLECULAR-BEAM EPITAXY
(1994-03-21)
CHENG, TM
;
CHIN, A
;
CHANG, CY
;
HUANG, MF
;
HSIEH, KY
Low temperature InGaAs strained quantum wells have been grown by molecular beam epitaxy and annealed at 600-900-degrees-C for 10 min. For an optimized annealing condition, arsenic precipitates can be successfully confined in the InGaAs wells and completely depleted in the GaAs barriers. The strong accumulation of As precipitates shows that the phenomena are not due to the strain effect but may be explained by the difference of interfacial energy between precipitate and matrix. The ability to control the As precipitates into two-dimensional quantum wells in LT materials has unique applications in a wide variety of devices.
A GLOBAL APPROACH FOR GENERAL 0-1 FRACTIONAL-PROGRAMMING
(1994-03-24)
LI, HL
;
交大名義發表
;
資訊管理與財務金融系註：原資管所+財金所
;
National Chiao Tung University
;
Department of Information Management and Finance
Current methods of general 0-1 fractional programming (G-FP) can only find the local optimum. This paper proposes a new method of solving G-FP problems by a mixed 0-1 linear program to obtain a global optimum. Given a mixed 0-1 polynomial term xy where x is a 0-1 variable and 0 < y less-than-or-equal-to 1, we develop a theorem to transfer the xy term into a set of mixed 0-1 linear inequalities. Based on this theorem, a G-FP problem can be solved by a branch-and-bound method to obtain the global solution.
管管的詩畫世界
(1994-03-24)
管管
管管的詩畫世界
(1994-03-24)
管管
管管的詩畫世界
(1994-03-24)
管管
管管的詩畫世界
(1994-03-24)
管管
A CONSTRAINT VARIATION TREATMENT FOR ROTATING NUCLEAR INTRINSIC STATES IN THE LABORATORY SYSTEM
(1994-03-28)
LIN, L
;
交大名義發表
;
電子物理學系
;
National Chiao Tung University
;
Department of Electrophysics
The cranking model describes nuclear rotation in the rotating frame. However, the physical experiments are performed in the laboratory system. In this article, a constraint variation treatment is suggested to generate a set of single particle orbitals with rotational characteristics. By using this set of basis vectors, we can obtain a rotating nuclear intrinsic state which is observed in the laboratory system.
COMPLEX-VALUED NEURAL-NETWORK FOR DIRECTION-OF-ARRIVAL ESTIMATION
(1994-03-31)
YANG, WH
;
CHAN, KK
;
CHANG, PR
;
交大名義發表
;
電信工程研究所
A complex-valued neural network for the implementation of a direction of arrival (DoA) estimator is presented. The network is based on the linear prediction method, with data processed fully in the complex domain. Simulation results are given to demonstrate the effectiveness of the network performances.
QUANTIZATION-ERROR CURVE - A MEASURE OF SIMILARITY BETWEEN REQUANTISED IMAGES
(1994-03-31)
CHU, CH
;
HSUEH, YC
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資訊工程學系
;
Department of Computer Science
A new similarity measure between a digital image and its quantised version is presented. By calculating the quantisation error on each of a sequence of subdomains, we can obtain a quantisation error curve as a similarity measure. This measure outperforms the commonly used measure for estimating the similarity between requantised images.
BINDING-ENERGIES OF D- ION IN GAAS QUANTUM-WELL
(1994-04-01)
CHANG, YH
;
YEH, JJ
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SHEU, YM
;
WANG, CC
;
CHEN, TC
Magnetic field dependent binding energies of the D- ion in the center of a 210 angstrom GaAs quantum well are determined by temperature magneto-transport measurments. The binding energies increase from 2.1 meV at 2T to 4 meV at 8T, and are consistently higher than the transition energies ootained from magneto-optical measurements performed on the same sample. We conclude from these data that in the magneto-optical measurement the observed transitions are between ground and excited D- states.
NANOMETER THICK SI/SIGE STRAINED-LAYER SUPERLATTICES GROWN BY AN ULTRAHIGH-VACUUM CHEMICAL-VAPOR-DEPOSITION TECHNIQUE
(1994-04-01)
CHANG, TC
;
CHANG, CY
;
JUNG, TG
;
TSAI, WC
;
WANG, PJ
High quality Si/Si1-xGex superlattices having layers as thin as 1.5 nm have been grown by an ultrahigh vacuum/chemical vapor deposition system. High-resolution double-crystal x-ray diffraction, and conventional and high-resolution cross-sectional transmission electron microscopy were used to evaluate the crystalline quality of these superlattices. A dynamical x-ray simulation program was employed to analyze the experimental rocking curves. Excellent matches between experimental rocking curves and simulated ones were obtained for all superlattices with various periodicity. A cross-sectional transmission electron micrograph of an 80 period Si(4.2 nm)/Si0.878Ge0.122 (1.5 nm) superlattice, in which each individual layers was clearly resolved, demonstrated the capability of this growth technique for nanometer thick layer deposition.
CHARACTERIZATION OF SI/SIGE STRAINED-LAYER SUPERLATTICES GROWN BY AN ULTRAHIGH-VACUUM CHEMICAL-VAPOR-DEPOSITION TECHNIQUE
(1994-04-01)
CHANG, TC
;
CHANG, CY
;
JUNG, TG
;
TSAI, WC
;
HUANG, GW
High-resolution double-crystal X-ray diffraction and cross-sectional transmission electron microscopy were used to characterize the Si/SiGe strained-layer superlattices grown by the ultrahigh vacuum/chemical vapor deposition (UHV/CVD) system. A dynamical X-ray simulation was employed to analyze the experimental rocking curves. Good matches between the experimental rocking curves and the simulated ones demonstrate that the high quality Si/SiGe strained-layer superlattices with abrupt interface and excellent thickness and composition uniformity have been achieved. Thickness uniformity was further confirmed by the cross-sectional transmission electron microscopy. In addition, high-resolution double-crystal X-ray diffraction was proven to be a powerful technique for determining the doping level and the thickness of heavily doped contact layer in Si/SiGe device structures prior to further processing. Good wafer-to-wafer uniformity can be simultaneously achieved by the UHV/CVD technique; as a result, the UHV/CVD technique is readily applicable to manufacturing.
ANALYSIS OF A CUTOFF PRIORITY CELLULAR RADIO SYSTEM WITH FINITE QUEUING AND RENEGING/DROPPING
(1994-04-01)
CHANG, CJ
;
SU, TT
;
CHIANG, YY
;
電信工程研究所
;
電信研究中心
Queueing of new or handoff calls can minimize blocking probabilities or increase total carried traffic. This paper investigates a new cutoff priority cellular radio system that allows Smite queueing of both new and handoff calls. We consider the reneging from the system of queued new calls due to caller impatience and the dropping of queued handoff calls by the system as they move out of a handoff area before being accomplished successfully. We use signal-flow graphs and Mason's formula to obtain the blocking probabilities of new and handoff calls and the average waiting times. Moreover, an optimal cutoff parameter and appropriate queue sizes for new and handoff calls are numerically determined so that a proposed overall blocking probability is minimized.
LOW-TEMPERATURE-PROCESSED POLY-SI THIN-FILM TRANSISTORS USING SOLID-PHASE-CRYSTALLIZED AND LIQUID-PHASE-DEPOSITED GATE OXIDE
(1994-04-01)
YEH, CF
;
CHEN, CL
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YANG, YC
;
LIN, SS
;
YANG, TZ
Poly-Si thin-film transistor (TFT) devices using solid-phase-crystallized and liquid-phase-deposited gate oxide are, for the first time, realized by low-temperature processes (LTP) (<625-degrees-C) for future LCDs and 3-D integrated circuits. The method of liquid-phase deposition of SiO2 (LPD-SiO2) is described. The physical, chemical and electrical properties of the new dielectric layer are clarified. The TFT (W/L = 200 mum/10 mum) having an on-off current ratio of 10(6) at V(D) = 5 V, a field-effect mobility of 15 cm2/V.s at V(D) = 0.1 V, a threshold voltage of 5.6 V, and a subthreshold swing of 1.6 V/decade, exhibits sufficient performance for pixel transistors. The field-effect mobility is strongly dependent on channel length. Effective passivation of defects by plasma hydrogenation will be very essential to achieve higher performance.