Browsing by Author "Chou, Lei-Chun"

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2.5D Heterogeneously Integrated Bio-Sensing Microsystem for Multi-Channel Neural-Sensing Applications
(2014-01-01)
Huang, Po-Tsang
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Chou, Lei-Chun
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Huang, Teng-Chieh
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Wu, Shang-Lin
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Wang, Tang-Shuan
2.5D Heterogeneously Integrated Microsystem for High-Density Neural Sensing Applications
(2014-12-01)
Huang, Po-Tsang
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Wu, Shang-Lin
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Huang, Yu-Chieh
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Chou, Lei-Chun
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Huang, Teng-Chieh
Heterogeneously integrated and miniaturized neural sensing microsystems are crucial for brain function investigation. In this paper, a 2.5D heterogeneously integrated bio-sensing microsystem with mu-probes and embedded through-silicon-via (TSVs) is presented for high-density neural sensing applications. This microsystem is composed of mu-probes with embedded TSVs, 4 dies and a silicon interposer. For capturing 16-channel neural signals, a 24 x 24 mu-probe array with embedded TSVs is fabricated on a 5 x 5 mm2 chip and bonded on the back side of the interposer. Thus, each channel contains 6 x 6 mu-probes with embedded TSVs. Additionally, the 4 dies are bonded on the front side of the interposer and designed for biopotential acquisition, feature extraction and classification via low-power analog front-end (AFE) circuits, area-power-efficient analog-to-digital converters (ADCs), configurable discrete wavelet transforms (DWTs), filters, and a MCU. An on-interposer bus (mu-SPI) is designed for transferring data on the interposer. Finally, the successful in-vivo test demonstrated the proposed 2.5D heterogeneously integrated bio-sensing microsystem. The overall power of this microsystem is only 676.3 mu W for 16-channel neural sensing.
A +/- 6ms-Accuracy, 0.68mm(2) and 2.21 mu W QRS Detection ASIC
(2010)
Wang, Hui-Min
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Lai, You-Liang
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Hou, Mark C.
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Lin, Shih-Hsiang
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Yen, Brad S.
Healthcare issues arose from population aging. Meanwhile, electrocardiogram (ECG) is a powerful measurement tool. The first step of ECG is to detect QRS complexes. A state-of-the-art QRS detection algorithm was modified and implemented. By the dedicated architecture design, the novel ASIC is proposed with 2.21 mu W power consumption and 0.68mm(2) core area. It is the smallest QRS detection ASIC so far in the world. In addition, the positive prediction of the ASIC is 99.36% based on the MIT/BIH arrhythmia database certification.
A 100 MHZ 1920x1080 HD-PHOTO 20 FRAMES/SEC JPEG XR ENCODER DESIGN
(2008)
Chien, Ching-Yen
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Huang, Sheng-Chieh
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Lin, Shih-Hsiang
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Huang, Yu-Chieh
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Chen, Yi-Cheng
A JPEG XR chip for HD-Photo is implemented with 25 MM area in TSMC 0.18um CMOS 1P6M technology at 100MHz According to the simulation results, the 4:4:4 1920x1080 HD-Photo 20 frames/sec can be encoded smoothly.
A BIOMEDICAL ENTERTAINMENT PLATFORM DESIGN BASED ON MUSICAL RHYTHM CHARACTERISTICS AND HEART RATE VARIABILITY (HRV)
(2008)
Huang, Yu-Chieh
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Lin, Shih-Hsiang
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Chien, Ching-Yen
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Chen, Yi-Cheng
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Chou, Lei-Chun
Heart rate variability (HRV) is a measure of variations in the heart rate. Over the last 25 years, HRV analysis has became popular as a non-invasive research and clinical tool for indirectly investigating both cardiac and autonomic nervous system (ANS) function in both health and disease area. How the musical rhythmic characteristics, tempo and complexity, affect the performance of HRV is studied in this work. By understanding the relationship between music and the function of ANS, the novel biomedical entertainment platform is proposed and used for relaxation.
A Computational Model of the Relationship Between Musical Rhythm and Heart Rhythm
(2009)
Wang, Hui-Min
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Lin, Shih-Hsiang
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Huang, Yu-Chieh
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Chen, I-Cheng
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Chou, Lei-Chun
Heart rate variability (HRV) is a measure of variation in the heart rate. Over the last 25 years, HRV analysis has became utilized more often as a non-invasive research and clinical tool for indirectly investigating both cardiac and autonomic nervous system (ANS) functions in health and disease. In our experiment, 22 healthy subjects and four testing rhythm patterns are studied. How the three musical-rhythmic characteristics of tempo, complexity and drum sample affect the performance of HRV is discussed and a computational model with four factors is proposed. This relationship can help us to improve our life and health by music.
A double-sided, single-chip integration scheme using through-silicon-via for neural sensing applications
(2015-02-01)
Chang, Chih-Wei
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Chou, Lei-Chun
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Huang, Po-Tsang
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Wu, Shang-Lin
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Lee, Shih-Wei
We present a new double-sided, single-chip monolithic integration scheme to integrate the CMOS circuits and MEMS structures by using through-silicon-via (TSV). Neural sensing applications were chosen as the implementation example. The proposed heterogeneous device integrates standard 0.18 mu m CMOS technology, TSV and neural probe array into a compact single chip device. The neural probe array on the back-side of the chip is connected to the CMOS circuits on the front-side of the chip by using low-parasitic TSVs through the chip. Successful fabrication results and detailed characterization demonstrate the feasibility and performance of the neural probe array, TSV and readout circuitry. The fabricated device is 5x5 mm(2) in area, with 16 channels of 150 mu m-in-length neural probe array on the back-side, 200 mu m-deep TSV through the chip and CMOS circuits on the front-side. Each channel consists of a 5x6 probe array, 3x14 TSV array and a differential-difference amplifier (DDA) based analog front-end circuitry with 1.8 V supply, 21.88 mu W power consumption, 108 dB CMRR and 2.56 mu Vrms input referred noise. In-vivo long term implantation demonstrated the feasibility of presented integration scheme after 7 and 58 days of implantation. We expect the conceptual realization can be extended for higher density recording array by using the proposed method.
A Fully Integrated 8-Channel Closed-Loop Neural-Prosthetic SoC for Real-Time Epileptic Seizure Control
(2013-01-01)
Chen, Wei-Ming
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Chiueh, Herming
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Chen, Tsan-Jieh
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Ho, Chia-Lun
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Jeng, Chi
A novel thermal switch and variable capacitance implement by CMOS MEMS process approaching in micro electrostatic converter
(2012-11-01)
Chiou, Jin-Chern
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Chou, Lei-Chun
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Lai, You-Liang
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Huang, Sheng-Chieh
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電控工程研究所
This paper focuses on implementing a novel thermal switch and variable capacitance design by using commercially available CMOS MEMS process which can approach in a micro electrostatic converter system. In this system, there are two major parts. First is the variable capacitance, and the second is the thermal switch. In the variable capacitance, it implement by UMC 0.18 mu m one-poly seven-metal (1P7M) CMOS MEMS process. In the post process, the silicon-oxidation has been released and the gap between two metal layers filled with PDMS (Polydimethylsiloxane). Filling with PDMS is to significantly increase C-max. In the thermal switch design, there are two novel designs in this switch: first, the soft contact structure and post-processing fabrication; second, using residual stress to achieve large structural deformation and a new design of thermal switch. To create the soft contact structure, residual stress effect has been utilized to make different bending curvatures. According to the experiments, the layer metal 1 has the largest residual stress [1] effect that can achieve the largest deflection in z-axis. Because the residual stress of the layer metal 1 is negative, the structure will bend down after release, the largest contact area which has been set up to get the lowest contact miss ability. In the post-processing fabrication, 0.3 mu m thickness gold will be patterned on the contact tips. Due to gold, rather than Aluminum, has no oxidation issue, it has more reliability on preventing the problem of oxidation than Aluminum. In the new thermal actuator design, we design a novel folded-flexure [2,3] with the electro-thermal excitation to turn the switch on or off. In the prototype, the device size is 500 mu m x 400 mu m and the gap between two contact pads is 9 mu m in off-state. Depending on the experimental results, the C-max is 19.22 nF, and the C-min is 10.65 nF in variable capacitance. The switch can work stably at 3 V. and the working temperature and operating bandwidth are individually 20-200 degrees C. The natural frequency of the switch is 42.9 kHz and the response time is 14.28 Hz. (c) 2012 Elsevier Ltd. All rights reserved.
A Parylene-C based 16 Channels Flexible Bio-electrode for ECoG Recording
(2014)
Chou, Lei-Chun
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Tsai, Shang-Wei
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Chang, Wun-Lun
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Chiou, Jin-Chern
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Chiu, Tzai-Wen
Micro Electro Mechanical System (MEMS) technology is used in a bio-electrode for measuring electrocorticography (ECoG) signals in Sprague Dawley (SD) rats. The electrical signal in the rat brain is evoked by auditory stimulation and can be detected with newly developed bio-electrode sensors. A back-end system can record signals from eighteen positions. One signal was used as the ground signal, and one was used as the reference signal. The average results for 100 samples revealed the relationship between temporal resolution and spatial resolution of sixteen positions in the brain. The bioelectrode was fabricated with two parylene layers (10um, 1um) to cover the platinum metal wires. Oxygen plasma is used to etch the bioelectrode and to define a stable size and shape in production of batches of electrodes. To simplify implantation, the bioelectrode was designed to fit the curvature of SD rat head bones, and a special connector was used to transmit signals to the back-end system, which successfully recorded Auditory Evoked Potentials (AEP) signals after implant surgery.
A study of the relationship between two musical rhythm characteristics and heart rate variability (HRV)
(2008)
Lin, Shih-Hsiang
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Huang, Yu-Chieh
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Chien, Ching-Yen
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Chen, Yi-Cheng
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Chou, Lei-Chun
Heart rate variability (HRV) is a measure of variations in the heart rate. Over the last 25 years, HRV analysis has became more and more popular as a non-invasive research and clinical tool for indirectly investigating both cardiac and autonomic nervous system (ANS) function in both health and disease area. How the musical rhythmic characteristics, tempo and complexity, affect the performance of HRV is studied in this work. By understanding the relationship between music and the function of ANS, we can improve our life and health by music - non-invasively and simply.
A TSV-Based Bio-Signal Package With mu-Probe Array
(2014-02-01)
Chou, Lei-Chun
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Lee, Shih-Wei
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Huang, Po-Tsang
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Chang, Chih-Wei
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Chiang, Cheng-Hao
Bio-signal probes providing stable observation with high quality signals are crucial for understanding how the brain works and how the neural signal transmits. Due to the weak and noisy characteristics of bio-signals, the connected interconnect length between the sensor and CMOS has significant impact on the bio-signal quality. In addition, long interconnections with wire bonding technique introduce noises and lead to bulky packaged systems. This letter presents an implantable through-silicon via (TSV) technology to connect sensors and CMOS devices located on the opposite sides of the chip for brain neural sensing applications. With the elimination of traditional wire bonding and packaging technologies, the quality of bio-signal can be greatly improved.
A TSV-Based Heterogeneous Integrated Neural-Signal Recording Device with Microprobe Array
(2014-01-01)
Chou, Lei-Chun
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Lee, Shih-Wei
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Cheng, Chuan-An
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Huang, Po-Tsang
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Chang, Chih-Wei
Highly integrated and miniaturized neural sensing microsystems are crucial for brain function investigation and neural prostheses realization. This paper presents a TSV-based heterogeneous integrated neural-signal recording device with microprobe array. By TSV, microprobe array and CMOS circuit make connection on the opposite sides of the chip. By measurement results on electrical characteristics of devices and TSV, this recording device is ready for bio-medical applications.
Cooling Stimulation on Cerebral Cortex for Epilepsy Suppression with Integration of Micro-Invasive Electrodes and TE Coolers
(2013)
Chiou, Jin-Chern
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Chou, Lei-Chun
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Tsai, Shang-Wei
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Hou, Kuan-Chou
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Chang, Chih-Wei
Epilepsy suppression with cooling stimulation is the primary purpose for this study. In this dissertation, cooling stimulation was implemented and demonstrated on cerebral cortex of rats. Electrodes with needle structure was designed and fabricated by using MEMS technology to minimize the size of device. A TE cooler was used to create cooling source and it can be control via electrical current. A cooler component was integrated with an electrode and a TE cooler, in addition, a thermal sensor was also combined with it to detect temperature variation, which was affected by cooling cerebral cortex. The cooler components were implanted on surface of cerebral with deep brain stimulation and the thermal sensors were penetrated into cortex to measure temperature variation which can verify the functions of cooler components. In our experimental results, electrodes with needle structure can improve efficiency of epilepsy suppression due to the particular structure. Duration, frequency and average single time of epileptic waveforms were used to identify to performance of suppression.
Demonstration of Implantable Grid Electrode/3-Dimensional Probe Array for ECOG and Extracellular Neural Recording on Rat
(2012)
Chou, Lei-Chun
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Chang, Chih-Wei
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Chiou, Jin-Chern
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電機工程學系
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Department of Electrical and Computer Engineering
This demonstration presents implantable grid electrodes array and three dimensional microprobe array for neural sensing on free-behaved laboratory rats. A flexible grid electrode array is fabricated for ECoG signal acquiring brain surface signal with 12-um thick parylene-C substrate and platinum sensing electrode. Flexible electrode array provides perfectly fitted to brain surface curvature. The 3D probe array are fabricated by MEMS process with new stacking method for 3D biopotential acquisition in the implanted target volume of tissue. Practical in-vivo recordings including auditory response, brain resection tissue and PZT-induced seizures recording demonstrate the correct function of the proposed neural recording devices.
Develop a novel thermal switch through CMOS MEMS fabrication process
(2011-01-01)
Lai, You-Liang
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Chou, Lei-Chun
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Juang, Ying-Zong
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Tsai, Hann-Huei
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Huang, Sheng-Chieh
This paper focuses on implementing two novel CMOS-MEMS type switches: buckling type and thermal type, by using commercially available TSMC 0.35 mu m two-poly four-metal (2P4M) CMOS process. There are two novel designs in these two type switches: first, the soft contact structure with post-processing fabrication; second, using residual stress to achieve large structural deformation in buckling type and thermal type switches. To create the soft contact structure, residual gradient stress effect has been utilized to make bending-down curvatures. According to the experiments, the layer Metal1 has the largest negative residual gradient stress [1] effect that can achieve the largest negative deflection in z-axis. Because the structure will bend down after post-processing release, larger lateral contact area are set up to gain the lower contact miss ability. In the post-processing fabrication, 0.3 mu m thickness gold will be deposited on the contact tips. Due to the essence of gold, comparing with aluminum, has no oxidation issue, gold also has the advantage of higher conductivity to reduce the electrical power loss. In the buckling type design, the switch uses residual stress to achieve lateral buckling effect to solve long distance problem. In the thermal type design, this paper design a folded-flexure [2, 3] with the electro-thermal excitation to turn the switch on or off. In the prototype, the device size is 500 mu m x 400 mu m and the gap between two contact pads is 9 mu m in off-state. on the experimental results, the switch can work stably at 3 volts, and the displacement of the thermal type switch can achieve 2.7 mu m, which is sufficient for the mechanism of switching-on or switching-off.
Integrated Microprobe Array and CMOS MEMS by TSV Technology for Bio- Signal Recording Application
(2014-01-01)
Chou, Lei-Chun
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Lee, Shih-Wei
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Huang, Po-Tsang
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Chang, Chih-Wei
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Wu, Shang-Lin
Bio-signal probes that provide stable observation with high-quality signals are crucial for understanding how the brain works and how the neural signal transmits. Because bio-signals are weak and noisy, the length of the string connecting the sensor and Complementary Metal-Oxide-Semiconductor (CMOS) circuit significantly impacts biosignal quality. The collected weak signals from the sensor must pass through a series of interconnections and interfaces that introduce noise and lead to bulky packaged systems. This work uses through-silicon via (TSV) technology to connect the mu-probe array bio-sensor and CMOS circuit located on opposite sides of a chip for brain neural sensing applications. With the elimination of wire bonding and the reduction of the soldering, bio-signal quality can be significantly improved.
Miniaturized Cortex Cooling Device and System for Hypothermia Therapy Application on Freely Moving Rat
(2012)
Chang, Chih-Wei
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Hou, Kuan-Chou
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Chou, Lei-Chun
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Chiou, Jin-Chern
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Chiou, Jin-Chern
This paper presents a miniaturized brain cortex cooling device and system using thermoelectric (TE) cooler for hypothermia therapy application on freely moving rat. Two type of cooling electrodes including planar and micro-needle structures are fabricated and studied by EEG recording. Comparing to prior arts, our approach can be applied under freely moving behavior. The cooling temperature is designed as 2 degrees C to avoid permanent injury in brain. Packaged planar or needle electrode with TE cooler consumes only 2x2mm2. EEG recording electrodes and thermocouple are implanted for observation as well. Simulation result shows that TE-cooler with needle type electrode behaves deeper effective cooling depth and faster cooling response in rodent cortex range (similar to 2mm deep). Long term EEG monitoring on freely moving rat also presents no extra side effects with continuously cooling.
The Relationship between Music Processing and Electrocardiogram (ECG) in Vegetative State (VS)
(2010)
Yen, Brad S.
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Wang, Hui-Min
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Hou, Mark C.
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Huang, Sheng-Chieh
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Chou, Lei-Chun
Previous literature has suggested that consciousness of patients in vegetative state (VS) may be enhanced via music listening; however, studies empirically documenting the link among music, vegetative state, and electrocardiogram (ECG) are scant. Therefore, the current article attempts to explore how music improves the VS patient's condition with the assessment of ECG recordings. The present work involved a follow-up of case report, consisting of forty-two 150-min sessions, whose duration is longer than other VS studies. The quantitative analysis of the data was conducted through C programming language, HRV Analysis, EXCEL and MATLAB package software in order to find a specific pattern of HRV. Results of the study showed a medium level of consistence between the two variables of music and ECG. To conclude, this publication may be of importance in presenting some specific pattern of the ECG diagram while letting VS patients listen to the music.
Thermal switch design by using complementary metal-oxide semiconductor MEMS fabrication process
(2011-07-01)
Chiou, Jin-Chern
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Chou, Lei-Chun
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Lai, You-Liang
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Juang, Ying-Zong
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Huang, Sheng-Chieh
The present study focuses on implementing a complementary metal-oxide semiconductor (CMOS) microelectromechanical system thermal switch by using the commercially available Taiwan Semiconductor Manufacturing Company (TSMC) 0.35 mu m two-poly four-metal CMOS process. There are two novel designs: first, the soft contact structure and post-processing fabrication; second, a new design of thermal actuator. To create the soft contact structure, residual stress effect has been utilised to make different bending curvatures. According to the experiments, the layer metal-1 has the largest residual stress effect that can achieve the largest deflection in the z-axis. Because the residual stress of the layer metal-1 is negative, the structure will bend down after release, hence providing larger contact area, which has been set up to obtain the lowest contact miss ability. In the post-processing fabrication, 0.3 mu m thickness gold will be patterned at the contact tips. Since gold, rather than aluminium, has no oxidation issue, it has more reliability in preventing the problem of oxidation than aluminium. In the new thermal actuator design, the authors designed a novel folded-flexure with the electrothermal excitation to turn the switch on or off. In the prototype, the device size is 500 x 400 mu m and the gap between two contact pads is 9 mu m in off-state. Depending on the simulation results, the switch can work stably at 3 V, and the working temperature and operating bandwidth are individually 20-200 degrees C.