Browsing by Author "Lee, TL"

Now showing 1 - 9 of 9

A 5-GHz direct-conversion receiver with I/Q phase and gain error calibration
(2005)
Chen, WZ
;
Lee, TL
;
Lu, TY
;
電機學院
;
College of Electrical and Computer Engineering
This paper describes the design of a 5GHz direct conversion receiver with phase and gain errors calibration for WLAN application. Integrated both LNA and mixer in a single chip, the conversion gain of the RF receiver is switch-able to compromise between linearity and noise performance. In addition, calibration schemes are proposed to compensate gain and phase errors in the I/Q signal paths. By means of this technique, the measured phase error is reduced to be less than 0.6 degrees and gain error less than 0.2 dB. The receiver provides a conversion gain of 28.2 dB in the high gain mode and 11.6 dB in the low gain mode within the signal bandwidth. The overall noise figure is 6.4dB in the high gain mode, and the third-order input intercept point (IIP3) is about -6.8dBm in the low gain mode. Implemented in a 0.18-mu m CMOS technology, it consumes 37.4 mW from a 1.8 V supply. Chip area is 1.64 mm(2).
Highly reliable nickel silicide formation with a Zr capping layer
(2003-05-01)
Lee, TL
;
Lee, JW
;
Lee, MC
;
Lei, TF
;
Lee, CL
Zr is proposed to be the capping layer for nickel silicide to obtain a stable low resistance contact system even at an annealing temperature as high as 850degreesC. A NiSi monolayer is the only phase observed in those samples annealed from 500 to 850degreesC. Experimental results from transmission electron microscopy and X-ray diffractometry analysis show that the agglomeration and precipitate of nickel silicide problems which are usually encountered in the NiSi system are eliminated. (C) 2003 The Electrochemical Society.
Impacts of HF etching on ultra-thin core gate oxide integrity in dual gate oxide CMOS technology
(2003)
Lee, DY
;
Lin, HC
;
Chen, CL
;
Huang, TY
;
Wang, TH
In this paper, we investigate the effects of HF etching on the integrity of ultra-thin oxides in dual gate oxide (DGO) CMOS technologies. We found that both the BF concentration in the etching solution and the over etching (OE) time are important parameters that greatly affect the device performance and reliability. Our results indicate that, with a proper over etching period, using a heavy BF solution results in better ultra-thin gate oxides in terms of reduced defect density, improved device performance and reliability, compared to using diluted BF solution. It is also found for the first time that negative-bias-temperature instability (NBTI) immunity for PMOSFETs is improved by using heavy HF solution.
Improvement of junction leakage by using a Zr cap layer on a 30 nm ultrashallow nickel-silicide junction
(2005)
Lee, TL
;
Lee, MZ
;
Lei, TF
;
Lee, CL
;
電子工程學系及電子研究所
This paper investigates the effects of Zr capping on nickel silicided n(+)/p shallow junctions. Although nickel silicide possesses many benefits compared with titanium and cobalt silicide, some potential problems still need to be addressed for ultrashallow junction applications. In this work, a Zr protective cap is used to preserve the silicide from oxygen contamination and to suppress the increase of junction leakage during the silicidation process. Due to the suppressed leakage current and the appropriate series resistence, formation of a 30 nm ultrashallow junction can be accomplished. (C) 2005 The Electrochemical Society.
Interfacial mechanism studies of electroless plated Cu films on a-Ta : N layers catalyzed by PIII
(2002-05-01)
Lin, JH
;
Lee, TL
;
Hsieh, WJ
;
Lin, CC
;
Kou, CS
This study evaluated the interface reaction and crystallography of the electroless plated copper film (similar to0.2 mum thick) catalyzed by plasma immersion ion implanted (PIII) Pd on the 150-Angstrom-thick amorphous tantalum nitride (a-Ta:N) barrier layer. The copper plated specimens were annealed at various temperatures in an ambient atmosphere of 90% nitrogen + 10% hydrogen mixed gases. Sheet resistivity, Auger electron spectroscopy (AES) analyses showed that the PIII Pd atoms were diffused into the copper layer from the interface of a-Ta:N and copper layers after 500 degreesC annealing for 1 h. Results based on x-ray diffraction (XRD) and high-resolution transmission electron microscopy (HRTEM) showed a phase transformation from a-Ta:N into crystallized Ta2N phase at annealing. The Cu(111) texture was strengthened at 300degreesC annealing for I h because of the relaxation of the residual stress and recovery of the copper film. The texture was reduced at the 500 degreesC annealing for I h because of the copper grain growth. The adhesion strength of copper films on a-Ta:N barrier layer was enhanced by the annealing because of the interdiffusion of copper layer, Pd clusters and a-Ta:N barrier layer. The annealing temperatures lower than 300 degreesC help to reduce the electric resistivity of copper film, to strengthen the Cu(111) preferred orientation. and to enhance the adhesion strength of copper films on a-Ta:N layer. However, the specimen annealed at 500 'C manifested the diffusion of Pd atoms into the copper film and resulted in a significant increase of the electric resistivity of copper film. (C) 2002 American Vacuum Society.
Transient three-dimensional convection of air in a differentially heated rotating cubic cavity
(1996-04-01)
Lee, TL
;
Lin, TF
;
機械工程學系
;
Department of Mechanical Engineering
Transient three-dimensional mixed convection of air in a differentially heated vertical cubic cavity rotating about a vertical axis through the cavity center is numerically investigated. The unsteady Navier-Stokes and energy equations were discretized by the power-law scheme and solved by the projection method. Results were obtained for the thermal and rotational Rayleigh and Taylor numbers all varied from 10(2) to 10(7). Effects of the centrifugal and Coriolis forces on the thermal buoyancy driven flow were examined in detail. Significant flow modification was noted when Ra-omega > Ra or Ta > Ra. It was noted in a rotational buoyancy dominated flow that after the initial transient the main flow structure is characterized by a symmetric pair of longitudinal rolls with their axes parallel with the rotating axis of the cavity. The increase in the Coriolis force decelerates the flow near the walls and reduces the heat transfer. The local Nusselt number distributions on the hot and cold plates were more sensitive to the change in the driving forces than the space average Nusselt numbers.
Transient three-dimensional convection of air in a differentially heated rotating cubic cavity
(1996-04-01)
Lee, TL
;
Lin, TF
;
交大名義發表
;
機械工程學系
;
National Chiao Tung University
Transient three-dimensional mixed convection of air in a differentially heated vertical cubic cavity rotating about a vertical axis through the cavity center is numerically investigated. The unsteady Navier-Stokes and energy equations were discretized by the power-law scheme and solved by the projection method. Results were obtained for the thermal and rotational Rayleigh and Taylor numbers all varied from 10(2) to 10(7). Effects of the centrifugal and Coriolis forces on the thermal buoyancy driven flow were examined in detail. Significant flow modification was noted when Ra-omega > Ra or Ta > Ra. It was noted in a rotational buoyancy dominated flow that after the initial transient the main flow structure is characterized by a symmetric pair of longitudinal rolls with their axes parallel with the rotating axis of the cavity. The increase in the Coriolis force decelerates the flow near the walls and reduces the heat transfer. The local Nusselt number distributions on the hot and cold plates were more sensitive to the change in the driving forces than the space average Nusselt numbers.
Trench gap-tilling copper by ion beam sputter deposition
(2006-05-10)
Han, S
;
Lee, TL
;
Yang, CJ
;
Shih, HC
;
材料科學與工程學系
The ion beam sputter deposition (IBSD) and electroless plating techniques have been combined to achieve the precipitation of Cu onto an amorphous (a)-TaN diffusion barrier layer in order to accomplish the ultralarge-scale-integrated interconnect metallization. The copper-filled specimens were annealed at various temperatures in a reduced atmosphere. The preferred orientation was analyzed by X-ray diffraction, and field emission scanning electron microscopy was used to elucidate the growth mechanism of the trench-filled electroless deposited Cu film on the Cu seeded layer by IBSD. The Cu(1 1 1) texture was strengthened by annealing at 300 degrees C for 1 h. The surface roughness increased notably with increasing annealing temperature. The electrical resistivity of the as-deposited copper film (3.05 mu Omega cm) decreased with increasing annealing temperature. The major contribution of this study is to successfully combine the techniques of IBSD and electroless plating for the Cu gap-filling of submicron trenches with an excellent step coverage. (c) 2006 Published by Elsevier B.V.
Wafer bonding by Ni-induced crystallization of amorphous silicon
(2003-09-01)
Chao, CP
;
Wu, YCS
;
Lee, TL
;
Wang, YH
;
材料科學與工程學系
Wafer bonding by Ni-induced crystallization of amorphous silicon was investigated. It was found that wafers can be bonded through the crystallization of amorphous silicon at temperatures below 550 degreesC. Moreover, when 250 V was applied across the stacked samples, the bonding temperatures could be decreased to as low as 350 degreesC.