Browsing by Author "Chen, Chien-Hung"

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A 10Bit, 10MS/s, Low Power Cyclic ADC
(2013)
Chen, Chien-Hung
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Chen, Wei-Zen
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電子工程學系及電子研究所
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Department of Electronics Engineering and Institute of Electronics
A low power, small form factor, cyclic ADC is proposed. By replacing the MDAC with an open loop residual amplifier, it relaxes the gain bandwidth requirement of the operational amplifier to save power. The residual amplifier is background calibrated without extra replica to avoid performance mismatches, and also save area and power. Timing reschedule scheme is proposed for each conversion step to accelerate conversion speed. At 10 MS/s operation, the corresponding FOM is 0.45pJ/conv.-step. Fabricated in a 85nm CMOS technology, the chip size is 0.077mm(2).
A highly reliable multi-level and 2-bit/cell operation of wrapped-select-gate (WSG) SONOS memory with optimized ONO thickness
(2007)
Wu, Woei-Cherng
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Chao, Tien-Sheng
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Peng, Wu-Chin
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Yang, Wen-Luh
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Wang, Jer-Chyi
High-performance wrapped-select-gate (WSG) SONOS (silicon-oxide-nitride-silicon) memory cells with multi-level and 2-bit/cell operation have been successfully demonstrated. The source-side injection mechanism with different ONO thickness in WSG-SONOS memory was well investigated. The different programming efficiency of the WSG-SONOS memory with different ONO thickness can be explained by the lateral electrical field extracted from the simulation. Furthermore, multi-level storage is easily obtained and well V-th distribution is also presented. High program/erase speed (10us/5ms) and low programming current (3.5uA) are performed to achieve the multi-level operation with excellent gate and drain disturbance, second-bit effect, data retention and endurance.
A novel trapezoid fin pattern applicable for air-cooled heat sink
(2015-11-01)
Chen, Chien-Hung
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Wang, Chi-Chuan
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機械工程學系
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Department of Mechanical Engineering
The present study proposed a novel step or trapezoid surface design applicable to air-cooled heat sink under cross flow condition. A total of five heat sinks were made and tested, and the corresponding fin patterns are (a) plate fin; (b) step fin (step 1/3, 3 steps); (c) 2-step fin (step 1/2, 2 steps); (d) trapezoid fin (trap 1/3, cutting 1/3 length from the rear end) and (e) trapezoid fin (trap 1/2, cutting 1/2 length from the rear end). The design is based on the heat transfer augmentation via (1) longer perimeter of entrance region and (2) larger effective temperature difference at the rear part of the heat sink. From the test results, it is found that either step or trapezoid design can provide a higher heat transfer conductance and a lower pressure drop at a specified frontal velocity. The effective conductance of trap 1/3 design exceeds that of plate surface by approximately 38 % at a frontal velocity of 5 m s(-1) while retains a lower pressure drop of 20 % with its surface area being reduced by 20.6 %. For comparisons exploiting the overall thermal resistance versus pumping power, the resultant thermal resistance of the proposed trapezoid design 1/3, still reveals a 10 % lower thermal resistance than the plate fin surface at a specified pumping power.
DESIGN OF AN AUTOMATED FEEDBACK CONTROL COOLING SYSTEM FOR SWIR LINEAR IMAGE SENSOR APPLICATION
(2010)
Chen, Chien-Hung
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Chen, Chih-Wen
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Lin, Chun-Fu
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Liao, Tai-Shan
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Hwang, Chi-Hung
Our novel automated feedback temperature controlled cooling system consists of a temperature measurement circuit, a TE cooler, a thermistor, a microcontroller, and a digital-to-analog converter and PWM algorithms. The measurement accuracy of this temperature controlled TE system was better than 0.1 degrees C and can be used for maintaining an instrument's isothermal applications. The experimental results of SWIR linear image shows that the temperature can be stably maintained at -20 degrees C, the dark output current can be reduced almost 80mV (Integration time: 100 ms) and the SNR of pixel can be improved from 48dB to 83dB as well.
Electrochemical photocatalytic degradation of dye solution with a TiO2-coated stainless steel electrode prepared by electrophoretic deposition
(2013-08-01)
Lin, Wei-Chieh
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Chen, Chien-Hung
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Tang, Han-Yu
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Hsiao, Yu-Cheng
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Pan, Jill Ruhsing
This study demonstrates a new model for the treatment of azo dye wastewater by means of a heterogeneous photocatalytic degradation coupled with the homogeneous electrochemical Fenton reaction, and is called electrochemical photocatalytic (ECPC) degradation. Titanium dioxide-coated stainless steel (P25-TiO2/SS) mesh was employed as a photo-anode, covered with a uniform layer of P-25-TiO2 using electrophoretic deposition (EPD) in a 2-propanol suspension with 10(-4) M Zn(NO3)(2), at a deposition time of 1 min. After annealing in air at 350 degrees C for 1 h, a crack-free, porous P25-TiO2 layer of ca. 2.14 mu m was obtained. Potential bias was used to enhance the photocatalytic degradation of P25-TiO2/SS towards the target pollutant, azo dye orange G, in an undivided cell under ultraviolet light irradiation. Heterogeneous photocatalytic degradation and a homogeneous electro-Fenton reaction occurred in the system simultaneously when H2O2 and Fe2+ were electrochemically generated on the graphite cathode and photo-anode, respectively, under a suitable potential bias, enhancing the de-colorization and removal of total organic carbon. (C) 2013 Elsevier B.V. All rights reserved.
Experimentally Effective Clean Process to C-V Characteristic Variation Reduction of HKMG MOS Devices
(2013)
Chen, Chien-Hung
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Li, Yiming
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Chen, Chieh-Yang
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Chen, Yu-Yu
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Hsu, Sheng-Chia
In this work, the planar HKMG MOS devices are fabricated on (100) wafer with p-substrate. To improve the samples\' interface roughness between the Si/Ge film and the interface layer, three different clean treatments are considered to fabricate the MOS devices. Among processes, the experiment indicates that HF and water rinse can present hydrogen termination to bond silicon as a good passivation. The measured C-V curves and HRTEM of the fabricated samples show the interface roughness is improved significantly. The extracted shift of flat band voltage (Delta V-fb) and density of interface traps (D-it) have around 50% improvement.
Fast Analog Layout Prototyping for Nanometer Design Migration
(2011)
Weng, Yi-Peng
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Chen, Hung-Ming
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Chen, Tung-Chieh
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Pan, Po-Cheng
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Chen, Chien-Hung
This paper presents an analog layout migration methodology to quickly provide multiple layouts while keeping similar or better circuit performance. Unlike previous works that often generate a single layout that has exactly the same topology with the original layout, this new migration algorithm is able to provide results with different aspect ratios. First, various placement constraints, including topology, matching, and symmetry, are extracted from the original layout. The extracted constraints are hierarchically stored into a topology slicing tree. Placement is performed from the bottom tree nodes to the root tree node. In each tree node, multiple placements for the subtree are recorded. All possible placements under the constraints are recorded in the root node. This algorithm has been successfully applied to a variable gain amplifier and a folded cascode operational amplifier migrating from UMC 90nm to UMC 65nm. The experimental results validate that our approach can provide reasonable layouts, even a better result almost in no time.
High-Reliability Dynamic-Threshold Source-Side Injection for 2-Bit/Cell With MLC Operation of Wrapped Select-Gate SONOS in NOR-Type Flash Memory
(2010-09-01)
Wang, Kuan-Ti
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Chao, Tien-Sheng
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Wu, Woei-Cherng
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Yang, Wen-Luh
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Lee, Chien-Hsing
For the first time, a high-performance (tau(PGM) = 200 ns/tau(ERS) = 5 ms) cell with superior reliability characteristics is demonstrated in a NOR-type architecture, using dynamic-threshold source-side injection (DTSSI) in a wrapped select-gate silicon-oxide-nitride-oxide-silicon memory device, with multilevel and 2-bit/cell operation. Using DTSSI enables easy extraction of the multilevel states with a tight V(TH) distribution, a nearly negligible second-bit effect, superior endurance characteristics, and good data retention.
High-Speed Multilevel Wrapped-Select-Gate SONOS Memory Using a Novel Dynamic Threshold Source-Side-Injection (DTSSI) Programming Method
(2009-06-01)
Wang, Kuan-Ti
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Chao, Tien-Sheng
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Wu, Woei-Cherng
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Chiang, Tsung-Yu
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Wu, Yi-Hong
A. high programming speed with a low-power-consumption wrapped-select-gate poly-Si-oxide-nitride-oxide-silicon memory is successfully demonstrated using the novel dynamic threshold source-side-injection programming technique. The select gate embedded in such particular memory structure acts like a dynamic MOSFET resulting in programming current (I(PGM)) that can be enhanced in this DT mode, easily attaining a high programming speed of about 100 ns. It still doubles the memory density by achieving the 2-bit/cell operation with MLC under DT mode.
Identifying android malicious repackaged applications by thread-grained system call sequences
(2013-11-01)
Lin, Ying-Dar
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Lai, Yuan-Cheng
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Chen, Chien-Hung
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Tsai, Hao-Chuan
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資訊工程學系
Android security has become highly desirable since adversaries can easily repackage malicious codes into various benign applications and spread these malicious repackaged applications (MRAs). Most MRA detection mechanisms on Android focus on detecting a specific family of MRAs or requiring the original benign application to compare with the malicious ones. This work proposes a new mechanism, SCSdroid (System Call Sequence Droid), which adopts the thread-grained system call sequences activated by applications. The concept is that even if MRAs can be camouflaged as benign applications, their malicious behavior would still appear in the system call sequences. SCSdroid extracts the truly malicious common subsequences from the system call sequence 6 of MRAs belonging to the same family. Therefore, these extracted common subsequences can be used to identify any evaluated application without requiring the original benign application. Experimental results show that SCSdroid falsely detected only two applications among 100 evaluated benign applications, and falsely detected only one application among 49 evaluated malicious applications. As a result, SCSdroid achieved up to 95.97% detection accuracy, i.e., 143 correct detections among 149 applications. (C) 2013 Elsevier Ltd. All rights reserved.
In-situ Formation and Assembly of Gold Nanoparticles by Gum Arabic as Efficient Photothermal Agent for Killing Cancer Cells
(2013-10-01)
Liu, Ching-Ping
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Lin, Fong-Sian
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Chien, Chih-Te
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Tseng, Sheng-Yang
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Luo, Chih-Wei
Invasiveness and surgical timing evaluation by clinical features of ground-glass opacity nodules in lung cancers
(1970-01-01)
Chen, Pai-Hsi
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Chang, Kuo-Ming
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Tseng, Wei-Chi
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Chen, Chien-Hung
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Chao, Jui-I
Background The early stages of lung cancer with ground-glass opacity (GGO) pattern are detectable. However, it remains a challenge for physicians how best to treat GGO nodules as invasive tumors are occasionally found, even in pure GGO nodules. This study identified the invasiveness by the clinical features of the GGO nodules. Methods A retrospective review of patients with resected GGO nodules from August 2015 to February 2019 was performed. A total of 92 patients were enrolled and gender, age, tumor location, operation times, tumor size, histopathologic and radiological findings were analyzed. Results In this study, the sequential of GGO nodules invasiveness was significantly related to the tumor size and solid component. After regrouping the population into preinvasive and invasive groups, the invasiveness was significantly related to tumor size, solid component, tumor volume and maximal computed tomography (CT) value. Conclusions The invasiveness is difficult to evaluate according to the CT features only when the GGO nodules are less than 2 cm and consolidation/tumor ratio (C/T ratio) are less than 0.25. Tumor size and solid component are significant factors for predicting invasiveness. Part-solid GGO nodules with a diameter greater than 1 cm require surgical consideration due to their high risk of invasiveness.
Manipulating Polycrystalline Silicon Nanowire FET Characteristics by Light Illumination
(2016-03-17)
Chen, Chien-Hung
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Lin, Chih-Heng
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Yang, Yuh-Shyong
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Hwang, Chi-Hung
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生物科技學系
Polycrystalline silicon nanowire field-effect transistor (poly-SiNW FET) has attracted many attentions in the past decade because of its ultrasensitive, label-free, and real-time response for potential sensing applications particular for biosensors. In this paper, the changes of the electric characteristics of poly-SiNW FET introduced by light illumination are studied systematically. Particularly, the red light (635 nm) and UV light (365 nm) are employed as light sources. Both lights are projected on the poly-SiNW FETs installed and are tested in air or in a vacuum (0.1 Ton) chamber. The results show that both light sources can change the electric characteristics of poly-SiNW FET which indicates that the photoelectronic effect can manipulate both n- and p-type devices of poly-SiNW FET; meanwhile, results also support the potential of poly-SiNW FET in air and in the vacuum environment for optoelectronic sensing applications.
Mobility model extraction for surface roughness of SiGe along (110) and (100) Orientations in HKMG bulk FinFET devices
(2013-09-01)
Chen, Chien-Hung
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Li, Yiming
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Chen, Chieh-Yang
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Chen, Yu-Yu
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Hsu, Sheng-Chia
In this work, the FinFET HKMG MOS devices are fabricated on silicon wafer with p-substrate. The interface roughness between the SiGe and SiO2 is experimentally extracted and calculated as a function of root mean square by analysis of high resolution transmission electron microscopy. The surface-roughness dependent mobility model is then incorporated into device simulation to study the mobility of SiGe along (110) and (100) orientations of the devices. We further analyze four devices with different surface roughness along (100) and (100) orientations to demonstrate the influence of surface roughness on the total effective mobility. (C) 2013 Elsevier B.V. All rights reserved.
Nickel-catalysed para-CH activation of pyridine with switchable regioselective hydroheteroarylation of allylarenes
(2015-01-01)
Lee, Wei-Chih
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Chen, Chien-Hung
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Liu, Cheng-Yuan
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Yu, Ming-Shiuan
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Lin, Yung-Huei
para-CH activation of pyridine with allylbenzene is described by Ni/Al cooperative catalysis in combination with a bulkier NHC ligand and a Lewis acid, leading to linear hydroheteroarylation products. Interestingly, the branch selectivity can be achieved by using the combination of a less sterically hindered amino-NHC ligand and AlMe3 through tandem reaction of facile alkene isomerization followed by a slow CH bond activation process.
Physical Mechanism of High-Programming-Efficiency Dynamic-Threshold Source-Side Injection in Wrapped-Select-Gate SONOS for NOR-Type Flash Memory
(2009-11-01)
Wang, Kuan-Ti
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Chao, Tien-Sheng
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Chiang, Tsung-Yu
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Wu, Woei-Cherng
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Kuo, Po-Yi
For the first time, a programming mechanism for conventional source-side injection (SSI) (normal mode), substrate-bias enhanced SSI (body mode), and dynamic-threshold SSI (DTSSI) (DT mode) of a wrapped-select-gate SONOS memory is developed with 2-D Poisson equation and hot-electron simulation and programming characteristic measurement for NOR Flash memory. Compared with traditional SSI, DTSSI mechanisms are determined in terms of lateral acceleration electric field and programming current (I(PGM)) in the neutral gap region, resulting in high programming efficiency. Furthermore, the lateral electric field intersects the vertical electric field, indicating that the main charge injection point is from the end edge of the gap region close to the word gate.
Preparation of Silicon Nanowire Field-effect Transistor for Chemical and Biosensing Applications
(2016-04)
Wu, Jennifer Yun-Shin
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Lin, Chih-Heng
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Feng, Mei-Huei
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Chen, Chien-Hung
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Su, Ping-Chia
Surveillance using biomarkers is critical for the early detection, rapid intervention, and reduction in the incidence of diseases. In this study, we describe the preparation of polycrystalline silicon nanowire field-effect transistors (pSNWFETs) that serve as biosensing devices for biomarker detection. A protocol for chemical and biomolecular sensing by using pSNWFETs is presented. The pSNWFET device was demonstrated to be a promising transducer for real-time, label-free, and ultra-high-sensitivity biosensing applications. The source/drain channel conductivity of a pSNWFET is sensitive to changes in the environment around its silicon nanowire (SNW) surface. Thus, by immobilizing probes on the SNW surface, the pSNWFET can be used to detect various biotargets ranging from small molecules (dopamine) to macromolecules (DNA and proteins). Immobilizing a bioprobe on the SNW surface, which is a multistep procedure, is vital for determining the specificity of the biosensor. It is essential that every step of the immobilization procedure is correctly performed. We verified surface modifications by directly observing the shift in the electric properties of the pSNWFET following each modification step. Additionally, X-ray photoelectron spectroscopy was used to examine the surface composition following each modification. Finally, we demonstrated DNA sensing on the pSNWFET. This protocol provides step-by-step procedures for verifying bioprobe immobilization and subsequent DNA biosensing application.
Sloped-Gate Voltage Method for Improving Measurement of Poly-Si Nanowire FET in Aqueous Environment
(2013-05-02)
Chen, Chien-Hung
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Su, Yi-Jr
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Lin, Chih-Heng
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Liao, Tai-Shan
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Yang, Yuh-Shyong
Nanowire field-effect transistors are suited to. study the activity of biomolecules in bionanotechnology. The changes of biomolecules process are efficiently affected the charge at the nanowire surface; thus, the electrical characterization of NW-FET is Changed. Although NW-FET is a well-known device in bioapplications, however, the intrinsic electrical characterization of NW-FET effect, on real electrical measurement is not well studied. We present herein a novel measurement method to avoid errors in electrical characteristic of nanowire field-effect transistors. A physical model is developed to explore the effect of the leakage current, which is influenced by the charging effect of an equivalent capacitor in a NW-FET. We also present a sloped-gate voltage method to reduce the effect, of equivalent capacitor in air, liquid, and phosphate buffered solution. The application of the sloped gate voltage Method significantly increases the stability of electrical characterization measurements. This method can also be easily applied to biosensing experiments.
Surface composition and interactions of mobile charges with immobilized molecules on polycrystalline silicon nanowires
(2015-05-01)
Lin, Chih-Heng
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Feng, Mei-Huei
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Hwang, Chi-Hung
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Wu, Jennifer Yun-Shin
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Su, Ping-Chia
The polycrystalline silicon nanowire field-effect transistor (poly-SiNW FET) is one of the most sensitive sensors used in real-time and label-free biosensing applications. Its low power requirement, mass production potential, and integrability with electronic components make it a highly attractive device in the rapidly growing diagnostic research field. From the viewpoint of device physics, the charges in the vicinity of a nanowire (NW) surface modulate the electrical characteristics of the NW device. The charges can originate from surface molecules or an ionic solution, and their role in NW biosensing systems remains to be clarified. Determining their role is crucial for understanding the physical interactions of charges in a biosensing event and for the realization of NW-based biosensors. Therefore, using poly-SiNW FET, we investigated the interactions of the immobilized molecules on the NW surface with the mobile charges in solutions. We also investigated the interactions between the mobile charged polymers and the immobilized molecules on the NW surface, and we observed the effect of charge neutrality, originating from Coulomb charge-charge interactions, on the NW conductance. Finally, the isoelectric points between native and sulfated PSGL-1 peptides on the NW surface were identified. This study provides a physical understanding of the charge-charge interaction of mobile charges with immobilized charged molecules on a nanoscale surface and presents new opportunities for using charge-based detection in biological and chemical sensing applications. (C) 2015 Elsevier B.V. All rights reserved.