Browsing by Author "Chiou, Jin-Chern"

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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 64-CHANNEL WIRELESS NEURAL SENSING MICROSYSTEM WITH TSV-EMBEDDED MICRO-PROBE ARRAY FOR NEURAL SIGNAL ACQUISITION
(2017-01-01)
Huang, Yu-Chieh
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Huang, Po-Tsang
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Hu, Yu-Chen
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Wu, Shang-Lin
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You, Yan-Huei
To enhance the signal integrity of high-density neural-sensing signals, this work presents an implantable high spatial resolution mu-probe array with through-silicon via (TSV) 2.5D integration technology that realizes a miniaturized implantable device on flexible printed circuit (FPC) interposer. The proposed microsystem was composed of two 32-channel neural sensing chips and one radio frequency chip for neural signal processing. The mu-probe array can achieve better signal-to-noise ratio with neural-signal acquisition and processing circuit composed of a pseudo-resistor-based analog front-end amplifier. Moreover, a receiving antenna is also implemented on the backside of FPC for wireless data and power transmission. The feasibility of the proposed mu-probe array, Tx and Rx antenna, 32-channel neural sensing circuits in the 64-channel wireless microsystem have been successfully demonstrated for future integration and animal experiments.
A capacitor-based sensor and a contact lens sensing system for intraocular pressure monitoring
(2016-01-01)
Chiou, Jin-Chern
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Huang, Yu-Chieh
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Yeh, Guan-Ting
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電機資訊學士班
;
電控工程研究所
This study proposes a capacitor-based sensor on a soft contact lens for the measurement of intraocular pressure (IOP). The sensor was designed and fabricated via microelectromechanical system fabrication technologies. The soft contact lens is designed to be worn on a cornea such that the curvature of the contact lens corresponds substantially to that of the cornea. In addition, the contact lens was fabricated via a cast-molding method using poly-2-hydroxyethyl methacrylate to achieve a lens with high oxygen permeability, which can be worn comfortably for a long time. An IOP sensor prototype was implemented, which exhibited 1.2239 pF mmHg(-1) (13,171 ppm mmHg(-1)) sensitivity during measurements of an artificial anterior chamber at pressures between 18 and 30 mmHg. The results indicate that the developed capacitor-based IOP sensor exhibited high stability and reproducibility in a series of measurements performed under various pressures. The capacitance of the proposed IOP sensor can successfully be converted into a digital value via a capacitor-to-digital converter and be transmitted via a commercial wireless telemetry system in this study.
A Comparison of Independent Event-Related Desynchronization Responses in Motor-Related Brain Areas to Movement Execution, Movement Imagery, and Movement Observation
(2016-09-16)
Duann, Jeng-Ren
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Chiou, Jin-Chern
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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
Electroencephalographic (EEG) event-related desynchronization (ERD) induced by movement imagery or by observing biological movements performed by someone else has recently been used extensively for brain-computer interface-based applications, such as applications used in stroke rehabilitation training and motor skill learning. However, the ERD responses induced by the movement imagery and observation might not be as reliable as the ERD responses induced by movement execution. Given that studies on the reliability of the EEG ERD responses induced by these activities are still lacking, here we conducted an EEG experiment with movement imagery, movement observation, and movement execution, performed multiple times each in a pseudorandomized order in the same experimental runs. Then, independent component analysis (ICA) was applied to the EEG data to find the common motor-related EEG source activity shared by the three motor tasks. Finally, conditional EEG ERD responses associated with the three movement conditions were computed and compared. Among the three motor conditions, the EEG ERD responses induced by motor execution revealed the alpha power suppression with highest strengths and longest durations. The ERD responses of the movement imagery and movement observation only partially resembled the ERD pattern of the movement execution condition, with slightly better detectability for the ERD responses associated with the movement imagery and faster ERD responses for movement observation. This may indicate different levels of involvement in the same motor-related brain circuits during different movement conditions. In addition, because the resulting conditional EEG ERD responses from the ICA preprocessing came with minimal contamination from the non-related and/or artifactual noisy components, this result can play a role of the reference for devising a brain-computer interface using the EEG ERD features of movement imagery or observation.
A Contact Lens Sensor System with a Micro-Capacitor for Wireless Intraocular Pressure Monitoring
(2013)
Huang, Yu-Chieh
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Yeh, Guan-Ting
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Yang, Tzu-Sen
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Chiou, Jin-Chern
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電控工程研究所
This paper proposes a novel micro-capacitor sensor for intraocular pressure (IOP) measurement on soft contact lens. The sensor was designed and fabricated by using MEMS fabrication technologies. The contact lens is for wearing on a cornea such that a curvature of the contact lens corresponds substantially to that of the cornea, and is preferably made of Hydroxyethylmethacrylate (HEMA) by cast-molding method of soft contact lens for high oxygen permeability and comfortable long-duration wearing. The prototype without wireless antenna has been implemented with a sensitivity of 0.43 pF/mmHg in measurement of human eye like balloon pressure test between 100 mmHg and 180 mmHg. The results show its high stability and reproducibility in a series of repeatable pressure variation. In future work the micro-capacitor will be tested on enucleated porcine eyes with better and integrated with a radio frequency integrated circuit and antenna on soft contact lens so that IOP value could be transferred to voltage value via capacitor to voltage converter and transmits IOP sensing signal by wireless telemetry system.
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 Low-Power Bio-Potential Acquisition System with Flexible PDMS Dry Electrodes for Portable Ubiquitous Healthcare Applications
(2013-03-01)
Chen, Chih-Yuan
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Chang, Chia-Lin
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Chang, Chih-Wei
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Lai, Shin-Chi
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Chien, Tsung-Fu
This work describes a bio-potential acquisition system for portable ubiquitous healthcare applications using flexible polydimethylsiloxane dry electrodes (FPDEs) and a low-power recording circuit. This novel FPDE used Au as the skin contact layer, which was made using a CO2 laser and replica method technology. The FPDE was revised from a commercial bio-potential electrode with a conductive snap using dry electrodes rather than wet electrodes that proposed reliable and robust attachment for the purpose of measurement, and attaching velcro made it wearable on the forearm for bio-potential applications. Furthermore, this study proposes a recording device to store bio-potential signal data and provides portability and low-power consumption for the proposed acquisition system. To acquire differential bio-potentials, such as electrocardiogram (ECG) signals, the proposed recording device includes a low-power front-end acquisition chip fabricated using a complementary metal-oxide-semiconductor (CMOS) process, a commercial microcontroller (MSP430F149), and a secure digital (SD) card for portable healthcare applications. The proposed system can obtain ECG signals efficiently and are comfortable to the skin. The power consumption of the system is about 85 mW for continuous working over a 3 day period with two AA batteries. It can also be used as a compact Holter ECG system.
A micromirror with large static rotation and vertical actuation
(2007-03-01)
Chiou, Jin-Chern
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Kou, Chin-Fu
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Lin, Yung-Jiun
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電控工程研究所
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Institute of Electrical and Control Engineering
A micromirror with large rotation angle and vertical displacement is proposed and developed. The proposed micromirror is actuated by newly developed prestress comb drive actuators, which exhibit no pull-in, no hysteresis, and large vertical displacement range characteristics. The micromirror was fabricated using commercially available PolyMUMPs. Experimental results indicated that the maximum rotation angle and vertical displacement of the device are 26 and 45 mu m, respectively.
A Novel Pseudo Resistor Structure for Biomedical Front-end Amplifiers
(2015)
Huang, Yu-Chieh
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Yang, Tzu-Sen
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Hsu, Shun-Hsi
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Chen, Xin-Zhuang
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Chiou, Jin-Chern
This study proposes a novel pseudo resistor structure with a tunable DC bias voltage for biomedical front-end amplifiers (FEAs). In the proposed FEA, the high-pass filter composed of differential difference amplifier and a pseudo resistor is implemented. The FEA is manufactured by using a standard TSMC 0.35 mu m CMOS process. In this study, three types FEAs included three different pseudo resistor are simulated, fabricated and measured for comparison and electrocorticography (ECoG) measurement, and all the results show the proposed pseudo resistor is superior to other two types in bandwidth. In chip implementation, the lower and upper cutoff frequencies of the high-pass filter with the proposed pseudo resistor are 0.15 Hz and 4.98 KHz, respectively. It also demonstrates lower total harmonic distortion performance of -58 dB at 1 kHz and higher stability with wide supply range (1.8 V and 3.3 V) and control voltage range (0.9 V and 1.65 V) than others. Moreover, the FEA with the proposed pseudo successfully recorded spike-and-wave discharges of ECoG signal in in vivo experiment on rat with pentylenetetrazol-induced seizures.
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 Power-Efficient Bio-Potential Acquisition Device with DS-MDE Sensors for Long-Term Healthcare Monitoring Applications
(2010-05-01)
Chang, Chia-Lin
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Chang, Chih-Wei
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Huang, Hong-Yi
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Hsu, Chen-Ming
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Huang, Chia-Hsuan
This work describes a power-efficient bio-potential acquisition device for long-term healthcare applications that is implemented using novel microelectromechanical dry electrodes (MDE) and a low power bio-potential processing chip. Using micromachining technology, an attempt is also made to enhance the sensing reliability and stability by fabricating a diamond-shaped MDE (DS-MDE) that has a satisfactory self-stability capability and superior electric conductivity when attached onto skin without any extra skin tissue injury technology. To acquire differential bio-potentials such as ECG signals, the proposed processing chip fabricated in a standard CMOS process has a high common mode rejection ratio (C. M. R. R.) differential amplifier and a 12-bit analog-to-digital converter (ADC). Use of the proposed system and integrate simple peripheral commercial devices can obtain the ECG signal efficiently without additional skin tissue injury and ensure continuous monitoring more than 70 hours with a 400 mAh battery.
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.
A Wearable and Wireless Gas-Sensing System Using Flexible Polymer/Multi-Walled Carbon Nanotube Composite Films
(2017-09-01)
Chiou, Jin-Chern
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Wu, Chin-Cheng
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電子工程學系及電子研究所
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電控工程研究所
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Department of Electronics Engineering and Institute of Electronics
In this study, an integrated flexible gas sensor was developed based on a polymer/multiwalled carbon nanotube composite film by using Bluetooth wireless communication/interface technology. Polymer/multi-walled carbon nanotube composite films were deposited over a polyimide flexible substrate for building a gas sensor array by using a drop-casting method. Sensor response was acquired through interdigitated electrodes and multi-channel sensor boards, which were linked to a Bluetooth wireless transceiver. Additionally, a double-spiral-shaped heater was built into the backside of the gas sensor array as a thermostat to protect it from the influence of ambient temperature. Multi-channel sensing responses were read on a display screen via a smartphone application (app). The advantages of this system include light weight, low cost, highly integrated sensors, wireless telecommunication, and real-time functioning. Thus, it is a promising candidate for deployment in a wearable gas-sensing system used to study air pollution.
A wearable infrared videopupillography with multi-stimulation of consistent illumination for binocular pupil response
(2016-01-01)
Ou-Yang, Mang
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Lan, Ko Mei
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Tsai, Yi-Chun
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Chiou, Jin-Chern
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Huang, Ting-Wei
The pupil response to light can reflect various kinds of diseases which are related to physiological health. Pupillary abnormalities may be influenced on people by autonomic neuropathy, glaucoma, diabetes, genetic diseases, and high myopia. In the early stage of neuropathy, it is often asymptomatic and difficulty detectable by ophthalmologists. In addition, the position of injured nerve can lead to unsynchronized pupil response for human eyes. In our study, we design the pupilometer to measure the binocular pupil response simultaneously. It uses the different wavelength of LEDs such as white, red, green and blue light to stimulate the pupil and record the process. Therefore, the pupilometer mainly contains two systems. One is the image acquisition system, it use the two cameras modules with the same external triggered signal to capture the images of the pupil simultaneously. The other one is the illumination system. It use the boost converter ICs and LED driver ICs to supply the constant current for LED to maintain the consistent luminance in each experiments for reduced experimental error. Furthermore, the four infrared LEDs are arranged nearby the stimulating LEDs to illuminate eyes and increase contrast of image for image processing. In our design, we success to implement the function of synchronized image acquisition with the sample speed in 30 fps and the stable illumination system for precise measurement of experiment.
A Wireless and Batteryless Microsystem with Implantable Grid Electrode/3-Dimensional Probe Array for ECoG and Extracellular Neural Recording in Rats
(2013-04-01)
Chang, Chih-Wei
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Chiou, Jin-Chern
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電機資訊學士班
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Undergraduate Honors Program of Electrical Engineering and Computer Science
This paper presents the design and implementation of an integrated wireless microsystem platform that provides the possibility to support versatile implantable neural sensing devices in free laboratory rats. Inductive coupled coils with low dropout regulator design allows true long-term recording without limitation of battery capacity. A 16-channel analog front end chip located on the headstage is designed for high channel account neural signal conditioning with low current consumption and noise. Two types of implantable electrodes including grid electrode and 3D probe array are also presented for brain surface recording and 3D biopotential acquisition in the implanted target volume of tissue. The overall system consumes less than 20 mA with small form factor, 3.9 x 3.9 cm(2) mainboard and 1.8 x 3.4 cm(2) headstage, is packaged into a backpack for rats. Practical in vivo recordings including auditory response, brain resection tissue and PZT-induced seizures recording demonstrate the correct function of the proposed microsystem. Presented achievements addressed the aforementioned properties by combining MEMS neural sensors, low-power circuit designs and commercial chips into system-level integration.
A Wirelessly Powered Smart Contact Lens with Reconfigurable Wide Range and Tunable Sensitivity Sensor Readout Circuitry
(2017-01-01)
Chiou, Jin-Chern
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Hsu, Shun-Hsi
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Huang, Yu-Chieh
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Yeh, Guan-Ting
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Liou, Wei-Ting
This study presented a wireless smart contact lens system that was composed of a reconfigurable capacitive sensor interface circuitry and wirelessly powered radio-frequency identification (RFID) addressable system for sensor control and data communication. In order to improve compliance and reduce user discomfort, a capacitive sensor was embedded on a soft contact lens of 200 mu m thickness using commercially available bio-compatible lens material and a standard manufacturing process. The results indicated that the reconfigurable sensor interface achieved sensitivity and baseline tuning up to 120 pF while consuming only 110 mu W power. The range and sensitivity tuning of the readout circuitry ensured a reliable operation with respect to sensor fabrication variations and independent calibration of the sensor baseline for individuals. The on-chip voltage scaling allowed the further extension of the detection range and prevented the implementation of large on-chip elements. The on-lens system enabled the detection of capacitive variation caused by pressure changes in the range of 2.25 to 30 mmHg and hydration level variation from a distance of 1 cm using incident power from an RFID reader at 26.5 dBm.