Browsing by Author "Shieh, JM"

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A new category of semiconductor nonlinear mirrors for ultrafast pulse generation and switching
(2001)
Pan, CL
;
Liu, TA
;
Shieh, JM
;
Huang, KF
;
光電工程學系
A new type of saturable Bragg reflector with record-low saturation fluence and broad tuning range
(1998)
Shieh, JM
;
Huang, TC
;
Huang, KF
;
Wang, CL
;
Pan, CL
The saturation fluence for a strained triple-quantum-well saturable Bragg reflector was as low as 12 mu J/cm(2) Self-starting femtosecond pulses tunable from 768 to 804nm was realized.
Aging influence of poly(ethylene glycol) suppressors of Cu electrolytes on gaps filling
(2006-05-01)
Liu, SH
;
Li, TC
;
Chen, C
;
Shieh, JM
;
Dai, BT
In this study, we investigate how the degradation of poly(ethylene glycol) (PEG) additives in Cu electroplating electrolytes influences the gaps filling of damascene features and the roughness of plated surfaces. The cleavage of PEG, whose reaction is enhanced by a high bias current and more plating cycles, not only diminishes the inhibition effect of the electrolytes, but also enables the formation of enormous complexes of short-chain PEG-Cu far from the reacting surfaces. Hence, the more plating cycles performed, the worse the gaps filling characteristic and the rougher the plated surfaces. Furthermore, an overshoot phenomenon on the transient cells voltage for PEG-containing electrolytes is observed and explained well by a dynamic equilibrium between PEG absorption ability and Cu reduction speed. Accordingly, the change in overshoot shape is closely related to PEG aging and this fact is employed to examine the reliability of electrolytes.
Broadly tunable self-starting passively mode-locked Ti : sapphire laser with triple-strained quantum-well saturable Bragg reflector
(1998-11-01)
Shieh, JM
;
Huang, TC
;
Huang, KF
;
Wang, CL
;
Pan, CL
We demonstrate broadband mode-locking of femtosecond Ti:sapphire lasers with a new type of saturable Bragg reflector (SBR). Triple-strained quantum wells with separate and sequential bandgaps were used as the absorbing layer. The saturation fluence was as low as 7 mu J/cm(2). Self-starting sub-100 fs pulses tunable from 768 to 804 nm were generated in a standard X-folded cavity without intracavity tight focusing on the SBR or temperature tuning. The threshold fluence for self-starting mode-locking was 1 mu J/cm(2). (C) 1998 Elsevier Science B.V. All rights reserved.
Broadly tunable self-starting passively mode-locked Ti : sapphire laser with triple-strained quantum-well saturable Bragg reflector
(1998-11-01)
Shieh, JM
;
Huang, TC
;
Huang, KF
;
Wang, CL
;
Pan, CL
We demonstrate broadband mode-locking of femtosecond Ti:sapphire lasers with a new type of saturable Bragg reflector (SBR). Triple-strained quantum wells with separate and sequential bandgaps were used as the absorbing layer. The saturation fluence was as low as 7 mu J/cm(2). Self-starting sub-100 fs pulses tunable from 768 to 804 nm were generated in a standard X-folded cavity without intracavity tight focusing on the SBR or temperature tuning. The threshold fluence for self-starting mode-locking was 1 mu J/cm(2). (C) 1998 Elsevier Science B.V. All rights reserved.
Characteristics of fluorinated amorphous carbon films and implementation of 0.15 mu m Cu/a-C : F damascene interconnection
(2001-05-01)
Shieh, JM
;
Suen, SC
;
Tsai, KC
;
Dai, BT
;
Wu, YC
Fluorinated amorphous carbon films (a-C:F) deposited by plasma enhanced chemical vapor deposition with low dielectric constant (K similar to2.3), thermal stability (higher than 400 degreesC) and acceptable adhesion to a cap layer such as SiOF or SiO2 were obtained by varying the range of content ratios between carbon and fluorine, the rf power, the process pressure and the base temperature. Standard x-ray photoelectron spectroscopy and thermal desorption spectroscopy metrologies were employed to characterize the deposited a-C:F films. The damascene pattern with 0.15 mum and an etching selectivity of more than 50 (a-C:F/SiOF, SiO2) was implemented by a mixture of etching gases of N-2+O-2. The bias power, rf power and gas hows were incorporated to optimize the etching recipe for achieving a damascene profile with a high aspect ratio. The scanning electron microscope results showed that a better etch profile can be obtained at higher bias power. In our damascene architecture, the etching stop layer or hard mask of both SiOF and SiO2 was studied. The SiOF, providing a lower dielectric constant than SiO2, would especially reduce the entire effective dielectric constant. Furthermore, we integrated electroplated copper into trenches or vias as small as 0.15 mum, with aspect ratio of 6. (C) 2001 American Vacuum Society.
Characterization and reduction of phase noise in passively mode-locked Ti : sapphire lasers with intracavity saturable absorbers
(1998-06-01)
Shieh, JM
;
Liu, SC
;
Pan, CL
;
光電工程學系
;
Department of Photonics
We characterize the phase noises (or timing jitter) of argon-ion-laser-pumped femtosecond Ti:sapphire lasers with intracavity dye saturable absorbers or saturable Bragg reflectors (SBR's). The significance of the finite lifetime of the absorbers is identified for what is the first time to our knowledge. We show that timing fluctuations of the mode-locked lasers can be suppressed significantly by optimization of intracavity gain bandwidth and group-velocity dispersion. A new active stabilization technique, based on the optoelectronic phase locked loop, is also demonstrated. The rms timing jitter (100-500 Hz) of the femtosecond passively mode-locked Ti:sapphire/dye and Ti:sapphire/SBR lasers operating at an average power of 200 mW is reduced to similar to 650 and 290 fs (500 Hz), respectively. (C) 1998 Optical Society of America.
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].
Dopant profile engineering by near-infrared femtosecond laser activation
(2006-03-27)
Wang, YC
;
Pan, CL
;
Shieh, JM
;
Dai, BT
;
光電工程學系
Femtosecond laser annealing (FLA) was employed for activation of phosphorus (P)- and boron (B)-implanted silicons with negligible dopant diffusion. Preamorphizing implantation is not required. We found that the dopant profiles in FLA-activated samples essentially duplicate those of as-implanted ones even for junctions as deep as 100 nm below the surface. The measured sheet resistances and activation efficiencies of P- and B-implanted samples were in the range of 100-400 Omega/square and 28%-35%, respectively. Moreover, thermal-energy-assisted dopant diffusion by heating was observed for substrate temperature as low as 100 degrees C. The shallow activated-depth feature associated with FLA reduces the separation between end-of-range defects and high-concentration portion of dopants. This generates a steep interstitial gradient responsible for observed B and P uphill diffusions at a depth of about 60 nm below the surface. (c) 2006 American Institute of Physics.
Dynamic pulse buildup in continuous-wave passively mode-locked picosecond Ti: Sapphire/DDI and Ti: Sapphire/IR140 lasers
(1999-08-01)
Pan, CL
;
Pu, NW
;
Shieh, JM
;
光電工程學系
;
Department of Photonics
We have studied both theoretically and experimentally the buildup of mode-locked pulses out of noise in continuous wave (cw) passively mode-locked Ti: sapphire lasers with DDI and IR140 dye saturable absorbers, which have significantly different optical properties. The evolution of the laser output from cw, to partial mode-locking, to complete mode-locking was investigated experimentally by measuring the contrast ratio of transient autocorrelation trace, the second-harmonic-generation (SHG) conversion efficiency, the fractional energy, optical and radio frequency (RF) spectra at consecutive delay times using the time-gating technique. Theoretically, we have simulated the pulse buildup numerically by adopting the two-level model for the saturable absorber. The experimental results are in good agreement with the predictions of numerical simulation.
Effects of intracavity dispersion on the starting dynamics of continuous-wave passively mode-locked Ti:sapphire/DDI lasers
(1996-07-15)
Shieh, JM
;
Twu, HM
;
Pan, CL
;
交大名義發表
;
光電工程學系
Through analysis of transient autocorrelation traces, we show that intracavity dispersion significantly affects the number of initially oscillating modes as well as the buildup of passive mode locking in picosecond and femtosecond lasers. (C) 1996 Optical Society of America
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.
Emission of bright blue light from mesoporous silica with dense Si (Ge) nanocrystals
(2005)
Cho, AT
;
Shieh, JM
;
Shieh, J
;
Lai, YF
;
Dai, BT
Three-dimensional Si (Ge) nanocrystals (NCs) were dispersed within the nanopores of mesoporous silica films by high-density plasma (HDP), low-density plasma, or implantation. Surface states of the resulting Si (Ge) NCs/silica arrays initiate blue-white photoluminescence (PL). HDP makes reactive species highly mobile and enables deposited NCs bonded with pore-wall well, therefore, efficiently constructing photoemission arrays. The mean density of HDP-synthesized semiconducting NCs is as high as 1 x 10(18)/cm(3). Accordingly, blue PL of arrays obtained with HDP, which is 4- 7 times stronger than those obtained with other methods, exhibits quantum-efficiency of 1%, near the reported value for green-to-red light emission from quantum-confined Si NCs. © 2005 The Electrochemical Society. All rights reserved.
Expanding the process window and reducing the optical proximity effect by post-exposure delay
(2001-08-01)
Ku, CY
;
Shieh, JM
;
Chiou, TB
;
Lin, HK
;
Lei, TF
In this investigation, a novel idea had been proposed to expand the process window and reduce the optical proximity effect (OPE) by employing post-exposure delay (PED). Our previous work presented a model to specify the resist linewidth according to PED time based on the neutralization mechanism of organic base and photogenerated acid. Based on the model, the exposure latitude and depth of focus can be extended for various pattern sizes by applying PED on linewidth broadening. Moreover, the dense-iso critical dimension bias, which is caused by OPE, can also be reduced when PED is performed. (C) 2001 The Electrochemical Society. [DOI: 10.1149/1.1383557] All rights reserved.
High-voltage amplifier uses simplified circuit
(2004-10-14)
Tsai, JI
;
Shieh, JM
;
Liao, TS
;
Teng, CC
;
交大名義發表
Improving the quality of electroplated copper films by rapid thermal annealing
(2003-03-01)
Chang, SC
;
Shieh, JM
;
Dai, BT
;
Feng, MS
;
Wang, YL
The leveler, 2-mercaptopyridine (2MP), increases the filling power of copper electroplating electrolytes in plating 0.15 mum vias, but forms the plated copper metals of small-grained column structures with high resistivity. In this,study, we used rapid thermal annealing (RTA) to effectively improve the film quality. After RTA at 400 degreesC for 30 s, the resistivity of Cu deposits was reduced from similar to16.1 to similar to2.4 muOmegacm. Moreover, the Cu(111) intensity of Cu deposits increased after RTA annealing. (C) 2003 American Vacuum Society. [DOI: 10.1116/1.1562641].
Investigation of carrying agents on microstructure of electroplated Cu films
(2002-11-01)
Shieh, JM
;
Chang, SC
;
Dai, BT
;
Feng, MS
;
材料科學與工程學系
Adding high molecular-weight polyethylene glycol (PEG) as a carrying agent benefits Cu electroplating from the viewpoint of an increase in both filling capability and films' conductivity, when plated in a lower current-density region. On electroplating in a higher current-density region, a gradually decreasing grain size from the top to bottom of Cu films occurs in the electrolyte without PEG or with PEG200. In comparison, sharp grains are formed for the mentioned multi-domain crystallization for those films deposited by the electrolyte containing PEG2000 or PEG6000 due to its lower surface tension which facilitates grain growth along the higher electric field. The used concentration of PEG was flexible due to the fact that the surface morphology, resistivity and deposition rate of deposited films remained almost unchanged over a wide PEG concentration range.
Investigation of inductively coupled plasma gate oxide on low temperature polycrystalline-silicon TFTs
(2002-06-01)
Tseng, CH
;
Chang, TK
;
Chu, FT
;
Shieh, JM
;
Dai, BT
By optimizing the inductively coupled plasma (ICP) oxidation condition, a thin oxide of 10 nm has been grown at 350degreesC to achieve excellent gate oxide integrity of low leakage current < 5x10(-8) A/cm(2) (at 8 MV/cm), high breakdown field of 9.3 MV/cm and low interface trap density of 1.5x10(11)/eV cm(2). The superior performance poly-Si TFTs using such a thin ICP oxide were attained to achieve a high ON current of 110 μA/μm at V-D=1 V and V-G = 5 V and the high electron field effect mobility of 231 cm(2)/V.S.
Investigation of superfilling and electrical characteristics in low-impurity-incorporated Cu metallization
(2002-08-01)
Shieh, JM
;
Chang, SC
;
Dai, BT
;
Feng, MS
;
材料科學與工程學系
Complete filling of 0.13-mum vias and deposition of Cu with a low resistivity of about 2.3 muOmega(.)cm were obtained using an electrolyte with 2-aminobenzothiazole (2ABT) as the filling promoter. Due to the moderate charge transfer polarization characteristic realized by the addition of 2ABT, the film resistivity and the activation energy for thermal grain growth were similar to those for electrolytes without it. After rapid thermal annealing (RTA) at 400degreesC for 30 s, the resistivity was further reduced to similar to1.9 muOmega(.)cm.
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.