Browsing by Author "Lee, Ming Ling"

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Comparison of ZnO and Ti-doped ZnO sensing membrane applied in electrolyte-insulator-semiconductor structure
(2018-04-15)
Lee, Ming Ling
;
Wang, Jer Chyi
;
Kao, Chyuan Haur
;
Chen, Hsiang
;
Lin, Chan Yu
In this paper, we demonstrate electrolyte-insulator-semiconductor devices for biochemical sensing applications prepared from ZnO and Ti-doped ZnO sensing membranes deposited on Si substrates by radio frequency sputtering. The structural, morphological, and compositional features of these deposited films with multitemperature annealing were studied using X-ray diffraction, atomic force microscopy, and X-ray photoelectron spectroscopy, respectively. Sensitivity, linearity, hysteresis, and drift rate were measured to determine the sensing and reliability performance of all fabricated devices. Compared to the ZnO electrolyte-insulator-semiconductor (EIS), the Ti-doped ZnO EIS sensor annealed at 700 degrees C exhibits a higher sensitivity of 57.56 mV/pH, lower hysteresis of 2.79 mV, and lower drift rate of 0.29 mV/h. For Ti-doped ZnO, sensitivities of 3.62 mV/mM and 6.42 mV/mM were obtained for urea and glucose sensing, respectively. The improvements are owing to Ti-doping, which produces a rougher sensing surface, a well-crystallized grain structure, and thinner silicate and SiO2 at the silicon-oxide interface.
Degradation of AlGaInP light emitting diodes under reverse-bias operations in salty water vapor
(2015-08-01)
Chen, Hsiang
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Chu, Li-Chen
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Lee, Ming Ling
;
Kang, Nai Chung
;
Shei, Shih-Chang
GaP-based light emitting diodes (LEDs) reliability tests are crucial to further development for high-performance LED lighting technology. In this study, we perform reverse-bias stress tests for LEDs in water vapor and salty water vapor ambient, respectively. The results indicate that salty water vapor can quickly degrade LEDs. To investigate the failure mechanisms, electrical measurements, forward-bias and reverse-bias electroluminescence images, and multiple material analyses have been taken to study the failure mechanism. Results indicate that NaCl clustering solids and atom diffusion may cause deformation of the electrode and enhance the degradation of the LEDs. (c) 2014 Elsevier Ltd. All rights reserved.
Degradation of InGaN/GaN LEDs under Forward-bias Operations in Salty Water Vapor
(2016)
Chen, Hsiang
;
Hsieh, Kun Min
;
He, Yun Yang
;
Chu, Li Chen
;
Lee, Ming Ling
Forward-bias stress in salty water vapor can quickly degrade the InGaN/GaN LEDs. To examine the weakness of the device, electrical, optical, and material analyses and characterizations were performed to investigate the failure mechanism. Corrosion of the electrode and Au atom diffusion might result in damages of the device. Results indicate that forward-bias stress in salty water vapor can quickly influence the material properties, optical behaviors, and electrical characteristics of the LED device.
Effects of N-2 and O-2 annealing on the multianalyte biosensing characteristics of CeO2-based electrolyte-insulator-semiconductor structures
(2014-04-01)
Kao, Chyuan Haur
;
Chen, Hsiang
;
Lee, Ming Ling
;
Liu, Che Chun
;
Ueng, Herng-Yih
A CeO2-based multi-analyte electrolyte-insulator-semiconductor (EIS) biosensor has been fabricated on silicon substrate. To enhance the material quality and sensing performance, annealing treatment in N-2 and O-2 ambient has been incorporated. To examine the annealing effects, material analyses were conducted using X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and atomic force microscopy (AFM) to identify optimal treatment conditions. Furthermore, sensing performance for various ions of Na+, K+, urea, and glucose has also been tested. Results indicate that the membrane annealed at 800 degrees C in O-2 ambience exhibited a better performance with higher multianalyte sensitivity and a lower drift rate compared with the membrane annealed in N-2 ambience. Oxygen in O-2 ambience may cause stronger reflow and fill in the oxygen vacancy so that the material properties and sensing capability can be improved in O-2 annealing ambience. (C) 2014 Elsevier B.V. All rights reserved.
Fabrication and characterization of cobalt nanoparticles on ZnO nanorods on a polished titanium substrate
(2015-08-01)
Lee, Ming Ling
;
Chen, Hsiang
;
Chen, Chin Pang
;
Chu, Li Chen
;
Wang, Sheng Hsin
Cobalt (Co) nanoparticles (NPs) are spread on ZnO nanorods (NRs) on a polished Ti substrate. To characterize the Co NPs on the ZnO NRs, multiple material analyses including field-emission scanning electron microscope (FESEM), energy dispersive X-ray spectroscopy (EDX), X-ray photoelectron spectroscopy (XPS), Fourier-transform infrared (FIR) spectroscopy and secondary ion mass spectroscopy (SIMS) are carried out to examine the nanocomposite. Results indicate that Co NPs may accuthulate on the top part of ZnO NRs because of their sticky property. The CoNPs/ZnO NRs/Ti nanocomposite shows promise for future ferromagnetic device applications. (c) 2015 Elsevier Ltd. All rights reserved.
Multianalyte biosensor based on pH-sensitive ZnO electrolyte-insulator-semiconductor structures
(2014-05-14)
Kao, Chyuan Haur
;
Chen, Hsiang
;
Lee, Ming Ling
;
Liu, Che Chun
;
Ueng, Herng-Yih
Multianalyte electrolyte-insulator-semiconductor (EIS) sensors with a ZnO sensing membrane annealed on silicon substrate for use in pH sensing were fabricated. Material analyses were conducted using X-ray diffraction and atomic force microscopy to identify optimal treatment conditions. Sensing performance for various ions of Na+, K+, urea, and glucose was also tested. Results indicate that an EIS sensor with a ZnO membrane annealed at 600 degrees C exhibited good performance with high sensitivity and a low drift rate compared with all other reported ZnO-based pH sensors. Furthermore, based on well-established pH sensing properties, pH-ion-sensitive field-effect transistor sensors have also been developed for use in detecting urea and glucose ions. ZnO-based EIS sensors show promise for future industrial biosensing applications. (C) 2014 AIP Publishing LLC.
Physical and electrical properties of flash memory devices with nickel oxide(NiO2) charge trapping layer
(2017-06-01)
Lee, Ming Ling
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Chen, Hsiang
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Kao, Chyuan Haur
;
Mahanty, Rama Krushna
;
Sung, Wei Kung
In this study, we proposed a metal-oxide high-k-oxide-silicon (MOHOS) memory device using a nickel oxide film as the charge trapping layer, and studied the effect of post-deposition rapid thermal annealing (RTA) on the physical and electrical properties. The physical properties were investigated via multiple material analysis techniques such as X-ray diffraction and atomic force microscopy. The optimal annealing temperature for depositing the charge trapping layer was determined through a thorough investigation of the memory window, program/erase (P/E) cycle, crystalline structure, and material composition. Compared to the as-deposited NiO2 film, a MOHOS-type memory device annealed at 900 degrees C in a nitrogen atmosphere exhibited improved memory characteristics, in terms of a larger window in the capacitance-voltage hysteresis, better data retention (lower charge loss of 11%), faster program and erase cycles, and endurance characteristics (104 P/E cycles) without any significant drift in the flat band voltage. Therefore, the MOHOS memory device with a NiO2 trapping layer is a very promising candidate for future memory device applications. (C) 2017 Elsevier Ltd. All rights reserved.
The CeO2 Sensing Membrane in Electrolyte-Insulator-Semiconductor for Bio-Sensor Applications
(2014)
Liu, Che Chun
;
Lee, Ming Ling
;
Chang, Kow Ming
;
Chang, Shan Wei
;
Chen, Hsiang
In the paper, the EIS structure with high-k CeO2 sensing film has more responsive to H+ relative to Na+ and K+. The CeO2 sensing membrane annealed with O-2 at 800 degrees C shows a higher sensitivity of 58.76 mV/pH, higher linearity, lower hysteresis voltage of 5.97 mV and lower drift rate of 0.96 mV/hr than the other conditions.
The Nitrogen Incorporated ZrO2 Charge Trapping Layers in Nonvolatile Memory Applications
(2014)
Lin, Chih Ju
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Lee, Ming Ling
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Chang, Kow Ming
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Chang, Shan Wei
;
Chen, Hsiang
In the study, the MOHOS-type memory using ZrO2 trapping layer with nitrogen incorporation and combined with rapid thermal annealing has been investigated. It can be found that the memory device by nitrogen incorporation annealed at 900 degrees C can improve memory device performance, including larger C-V hysteresis, faster P/E speed, better data retention, and. smaller charge loss about 7.7%.
The structural and electrical comparison of Y2O3 and Ti-doped Y2O3 dielectrics
(2017-02-15)
Lee, Ming Ling
;
Kao, Chyuan Haur
;
Chen, Hsiang
;
Lin, Chan Yu
;
Chung, Yu Teng
A Ti-doped Y2O3(Y2Ti2O5) dielectric on polycrystalline silicon followed by rapid thermal annealing results in improved characteristics including a higher effective dielectric constant, higher breakdown electric field, lower electron trapping rate, and larger charge-to-breakdown when compared with Y2O3. The performance of high-k Y2O3 and Y2Ti2O5 dielectrics were investigated using X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), atomic force microscopy (AFM), capacitance-voltage, and current density-voltage. Incorporating Ti into the Y2O3 dielectric imparts improvements in the structural and electrical performance of the material. The Y2Ti2O5 dielectric with 800 degrees C annealing treatment has the best performance among all the samples tested.