Browsing by Author "Hsu, SL"

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An integrated inventory model for a single vendor and multiple buyers with ordering cost reduction
(2001-10-13)
Woo, YY
;
Hsu, SL
;
Wu, SS
;
管理科學系
;
Department of Management Science
Forming strategic alliances and utilizing modern information technologies have been the two most important ways for firms to gain such competitive advantages as lower logistics costs and secure customers' loyalty. In this paper, we consider an integrated inventory system where a single vendor purchases and processes raw materials in order to deliver finished items to multiple buyers. The vendor and all buyers are willing to invest in reducing the ordering cost (e.g., establishing an electronic data interchange based inventory control system) in order to decrease their joint total cost. The amount of investment determines the planned ordering cost and hence affects their replenishment decisions. One major managerial implication from this ordering cost reduction is that the efforts to streamline and speedup transactions via the application of information technologies may result in a higher degree of coordination and automation among allied trading parties. An analytical model is developed to derive the optimal investment amount and replenishment decisions for both vendor and buyers. The exponential ordering cost function is then applied to our general model. and a numerical analysis is performed to provide interesting insights of the model. Numerical results show that the vendor and all the buyers can benefit directly from substantial cost savings by this ordering cost reduction investment. (C) 2001 Elsevier Science B.V. All rights reserved.
Deep sub-micron strained Si0.85Ge0.15 channel p-channel metal-oxide-semiconductor field-effect transistors (pMOSFETs) with ultra-thin N2O-annealed SiN gate dielectric
(2005)
Chen, CW
;
Chien, CH
;
Chen, YC
;
Hsu, SL
;
Chang, CY
We have investigated the electrical characteristics of strained Si0.85Ge0.15 channel p-channel metal-oxide-semiconductor field effect transistors (pMOSFETs) with ultra-thin N2O-annealed SiN gate dielectric. We have found that the thickness of SiGe channel has a great impact on the device characteristics. With controlling the SiGe layer thickness thinner than 15 nm, the device depict a subthreshold swing of 68 mV/A, the interface state density of 1 x 10(11) eV(-1) cm(-2), acceptable junction leakage, and more than 50% hole mobility improvement with respect to the Si channel device. Therefore, high quality interface between the gate dielectric and the strained SiGe channel can be achieved by using the N2O-annealed SiN gate dielectric.
Effects of postdeposition annealing on the characteristics of HfOxNy dielectrics on germanium and silicon substrates
(2006)
Cheng, CC
;
Chien, CH
;
Chen, CW
;
Hsu, SL
;
Yang, CH
We have systematically investigated the impact that postdeposition annealing (PDA) has on the physical and electrical properties of HfOxNy thin films sputtered on Ge and Si substrates. These two substrates display contrasting metal-oxide-semiconductor characteristics that we attribute to the different compositions of their interface layers (ILs). We observed an increased GeO2 incorporation into the HfOxNy dielectric and severe volatilization of the IL on Ge after higher PDA processing. These undesired phenomena in the HfOxNy/Ge gate stacks may be responsible for their different electrical properties with respect to those of the HfOxNy/Si gate stacks, i.e., a further scaling of the capacitance-equivalent thickness, a significant presence of fixed positive charges and electron-trapping sites, and a degradation of dielectric reliability. In addition, the anomalous low-frequency-like behavior of the high-frequency capacitance-voltage curves in inversion for the Ge capacitors was predicted from theoretical calculations. (c) 2006 The Electrochemical Society.
Enhanced luminance and thermal properties of poly(phenylenevinylene) copolymer presenting side-chain-tethered silsesquioxane units
(2005-11-01)
Chou, CH
;
Hsu, SL
;
Yeh, SW
;
Wang, HS
;
Wei, KH
We have synthesized, using the Gilch polymerization method, a new series of high-brightness, soluble copolymers (POSS-PPV-co-MEHPPV) of poly(p-phenylenevinylene) (PPV) containing side-chain-tethered polyhedral oligomeric silsesquioxane (POSS) pendent units and poly(2-methoxy-5-[2-ethylhexyloxy]-1,4-phenylenevinylene) (MEHPPV). This particular molecular architecture of POSS-PPV-co-MEHPPV copolymers possesses not only a larger quantum yield (0.85 vs 0.19) but also higher degradation and glass transition temperatures relative to those of pure MEHPPV. The maximum brightness of a double-layered-configured light-emitting diode (ITO/PEDOT/emissive polymer/Ca/Al) incorporating a copolymer of MEHPPV and 10 mol % PPV-POSS was 5 times as large as that of a similar light-emitting diode incorporating pure MEHPPV (2196 vs 473 cd/m(2)).
Impact of post-deposition-annealing on the electrical characteristics of HfOxNy gate dielectric on Ge substrate
(2005-06-01)
Cheng, CC
;
Chien, CH
;
Chen, CW
;
Hsu, SL
;
Yang, MY
We systematically investigated the effect of post-deposition-annealing (PDA) on the electrical characteristics of Ge MOS capacitors with hafnium-oxynitride gate dielectric. The higher PDA temperature and longer PDA time was found to obtain the lower equivalent oxide thickness (EOT) of HfOxNy/Ge gate stack, however, with a larger hysteresis width. A lower EOT of 19.5 angstrom with a low leakage current of 1.8 x 10(-5) A/cm(2) at V-G = -1V was achieved after 600 degrees C annealing for 5 min. The improved capacitor properties after the PDA may be closely related to the different compositions and thicknesses of the resultant interfacial layers.
Low-temperature growth of polycrystalline ge films on SiO2 substrate by HDPCVD
(2005)
Yang, MJ
;
Shieh, J
;
Hsu, SL
;
Huang, IJ
;
Leu, CC
Pure and high-quality polycrystalline Ge films have been deposited directly onto fully SiO2 covered substrates by high-density plasma chemical vapor deposition (HDPCVD) system. Only a tiny amount of O and C near the surface has been observed from X-ray photoelectron spectroscopy and Auger electron spectroscopy data, which may come from surface oxidation and contamination. Very pure Ge composition has been achieved in the bulk of the films. The cubic structure with primarily (111), (220), and (311) orientations of the Ge films is mainly composed of fine grains and can be unambiguously identified from X-ray diffraction patterns. Furthermore, successful Ge film depositions with nearly no incubation time are demonstrated using a mixture of GeH4/H-2 as process gas at 400 degrees C. Thickness vs. time analysis was performed by high-resolution transmission electron microscopy. The HDPCVD technique used was able to provide a simple, powerful, and reliable approach in the fabrication of polycrystalline Ge thin film transistors. (C) 2005 The Electrochemical Society.
Reliability of strained SiGe channel p-channel metal-oxide-semiconductor field-effect transistors with ultra-thin (EOT=3.1nm) N(2)O-annealed SiN gate dielectric
(2005-06-01)
Chen, CW
;
Chien, CH
;
Chen, YC
;
Hsu, SL
;
Chang, CY
The p-channel metal-oxide-semi conductor field-effect transistor (pMOSFET) with 50-nm-thick Si(0.85)Ge(0.15) channel and in ultra-thin (EOT = 3.1 nm) N(2)O-annealed SiN gate dielectric has been shown to have well-performing on/off and output characteristics. Several methodologies for the device reliability characterization, such as stress-induced-leakage-current (SILC), drain-avalanche-hot-carrier (DAHC) injection, channel hot-carrier (CHC) injection and negative-bias-temperature-instability (NBTI), have been used and the results were compared. In terms of the long-term degradation, the excellent quality of the N(2)O-annealed SiN gate dielectric can be firmly obtained because only negligible degradations have been found after stressing no matter which technique was employed. Even so, the experimental results have been compared and we found that the HC degradation is worse than the NBTI degradation and the channel-hot-carrier (CHC) stressing is the worst case for all kinds of reliability testing. Meanwhile, we have also verified that the interface state generation is the dominant mechanism responsible for the HC-induced degradation while the electron trapping dominates the device degradation for the NBTI stressing.
Reliability of strained SiGe channel p-channel metal-oxide-semiconductor field-effect transistors with ultra-thin (EOT=3.1nm) N2O-annealed SiN gate dielectric
(2005-06-01)
Chen, CW
;
Chien, CH
;
Chen, YC
;
Hsu, SL
;
Chang, CY
The p-channel metal-oxide-semi conductor field-effect transistor (pMOSFET) with 50-nm-thick Si0.85Ge0.15 channel and in ultra-thin (EOT = 3.1 nm) N2O-annealed SiN gate dielectric has been shown to have well-performing on/off and output characteristics. Several methodologies for the device reliability characterization, such as stress-induced-leakage-current (SILC), drain-avalanche-hot-carrier (DAHC) injection, channel hot-carrier (CHC) injection and negative-bias-temperature-instability (NBTI), have been used and the results were compared. In terms of the long-term degradation, the excellent quality of the N2O-annealed SiN gate dielectric can be firmly obtained because only negligible degradations have been found after stressing no matter which technique was employed. Even so, the experimental results have been compared and we found that the HC degradation is worse than the NBTI degradation and the channel-hot-carrier (CHC) stressing is the worst case for all kinds of reliability testing. Meanwhile, we have also verified that the interface state generation is the dominant mechanism responsible for the HC-induced degradation while the electron trapping dominates the device degradation for the NBTI stressing.
Study of thermal stability of nickel monogermanide on single- and polycrystalline germanium substrates
(2005-06-20)
Hsu, SL
;
Chien, CH
;
Yang, MJ
;
Huang, RH
;
Leu, CC
We have investigated the thermal stability of nickel monogermanide (NiGe) films formed by rapid thermal annealing on both single- and polycrystalline Ge substrates. We found that the NiGe phase is the only one present after nickel germanidation in the temperature range 400-700 degrees C. A fairly uniform NiGe film formed on the single-crystalline Ge; it possessed excellent resistivity (15.6 mu Omega cm) and was thermally stable up to 550 degrees C, but it degraded rapidly at higher temperatures as a result of agglomeration. In contrast, the NiGe film formed on the polycrystalline Ge exhibited much poorer thermal stability, possibly because of polycrystalline Ge grain growth, which resulted in columnar NiGe grains interlaced with Ge grains that had a dramatically increased sheet resistance. As a result, we observed that the sheet resistances of NiGe lines subjected to annealing at 500 degrees C depended strongly on the linewidth when this width was comparable with the grain size of the polycrystalline Ge. (c) 2005 American Institute of Physic's.
Suppressing phosphorus diffusion in germanium by carbon incorporation
(2005-11-24)
Luo, G
;
Cheng, CC
;
Huang, CY
;
Hsu, SL
;
Chien, CH
A problem in the Ge MOSFET process is that the phosphor-us for n-type doping in Ge diffuses very fast. It is very difficult to form the shallow source/drain p-n junctions. It is reported, for the first time, that the phosphorus diffusion in Ge during activation (or annealing) can be suppressed effectively owing to carbon incorporation.
Synthesis and characterization of fluorescent poly [fluorene-co-phenylene-1-(di-2-pyridylamine)] copolymer and its Ru(II) complex
(2004-10-01)
Dinakaran, K
;
Chou, CH
;
Hsu, SL
;
Wei, KH
;
材料科學與工程學系
2,2'-dipyridylamine substituted poly(fluorene-co-phenylene) copolymers with different concentrations of dipyridylamine have been synthesized by Suzuki polycondensation. These polymers were found to be soluble in organic solvents such as tetrahydrofuran, chloroform, and dimethylformamide. The photoluminescence of the copolymer was slightly blueshifted as the concentration of dipridylamine was increased. The introduction of dipyridylamine and the ruthenium complex into the polymer significantly improved the photoluminescence efficiency. (C) 2004 Wiley Periodicals, Inc.
Synthesis and characterization of luminescent polyfluorenes incorporating side-chain-tethered polyhedral oligomeric silsesquioxane units
(2005-02-08)
Chou, CH
;
Hsu, SL
;
Dinakaran, K
;
Chiu, MY
;
Wei, KH
Using Suzuki polycondensation, we have synthesized polyhedral silsesquioxane-tethered polyfluorene copolymers, poly(9,9'-dioctylfluorene-co-9,9'-bis[4-(N,N-dipolysilsesquioxane)aminophenyl]fluorene) (PFO-POSS), that have well-defined architectures. This particular PFO-POSS molecular architecture increases the quantum yield of polyfluorene significantly by reducing the degree of interchain aggregation; in addition, these copolymers exhibit a purer and stronger blue light by preventing the formation of keto defects.