30th Anniversary Special Edition

30 Years Retrospect of Instruments Today [ 下載 PDF ]

Din Ping Tsai

Single Atom Electron and Ion Sources and Their Applications [ 下載 PDF ]

Ing-Shouh Hwang, Hong-Shi Kuo, Che-Cheng Chang, Chun-Yueh Lin, Tien T. Tsong

Noble-metal covered tungsten (111) single-atom tips can be used as ideal point sources of electron and ion beams. It has been shown that noble-metal covered W(111) single-atom tips can be reliably prepared and their lifetimes are long enough for real applications. These tips are both thermally and chemically stable, and can be regenerated in vacuum when accidentally damaged or contaminated. The atomic stacking remains the same each time it is regenerated. The small opening angle, smallest emitting area, high brightness, high spatial wave coherence, and high stability of these single-atom electron sources make them highly desirable for many applications. Both the brightness and spatial coherency of these electron sources are orders of magnitude better than those of the state-ofthe- art electron sources used in electron microscopes. Ion beams have similar attributes also. Application of these sources may significantly improve the performance and expand the capabilities of current electron and ion microscopes, and open up many new possibilities in electron-beam and ion-beam based techniques.

The Design and Realization of an Energy-Compensation Type Inelastic Soft-X-Ray Scattering Instrumentation [ 下載 PDF ]

Shih-Wen Hwang, Di-Jing Huang, Hok-Sum Fung, Hsiao-Yu Huang, Huang-Wen Fu, Tse-Chuan Tseng, Duan-Jen Wang, Chien-Te Chen

The interaction between soft-X-rays and matter can provide valuable information on the electronic and magnetic structure of matter. Facilitated by the increasing brilliance of synchrotron radiation light sources, inelastic soft-X-ray scattering (ISXS) has become a powerful technique for studying the low energy electron excitations of advanced materials. In this article, we present the design of a novel ISXS instrumentation which design stems from the application of energy compensation principle and the development of active gratings. The experimental results demonstrate that the data acquisition efficiency of this energy-compensation type ISXS instrumentation can be 100 times higher than conventional designs, opening up new opportunities for probing the microscopic electronic and magnetic structure of matter.

Detection of Unstable Gaseous Species with a Step-Scan FTIR Absorption Spectrometer [ 下載 PDF ]

Li-Kang Chu, Yuan-Pern Lee

Conventional Fourier-transform infrared spectrometer (FTIR) cannot detect species with short lifetime. We employed step-scan FTIR coupled with ac/dc detection and multiple reflection of both IR probe beam and UV photolysis beam to establish time-resolved FTIR absorption spectrometry so as to detect in the laboratory several unstable gaseous species that are important in atmospheric chemistry: ClCO, ClCS, ClSO, CH₃SO₂, C₆H₅SO₂, CH₃OO, ClCOOH, CH₃SO, and CH₃C(O)OO via their IR absorption. The system is capable of 10 ns temporal resolution and 0.13 cm⁻¹ spectral resolution, but for radical studies we typically employed 1 µs temporal resolution and 1 cm⁻¹ spectral resolution to obtain spectra with improved S/N ratio.

Precision Measurements of Photodissociation Cross Sections of a Species of Unknown Concentration in an Impure Sample [ 下載 PDF ]

Chien-Yu Lien, Hsueh-Ying Chen, Wei-Yen Lin, Yuan T. Lee, Jim J. Lin

New measurements are usually essential to answer or direct an important question. And new measurements usually require new instruments. We heard of an important international problem in early 2008. After carefully analyzing the problem and our capabilities, we decided to take the challenge. Here we briefly introduce the problem, how to solve the problem, the instrument and eventually acquiring the most precise measurements.

Research on Efficiency Improvement of Light- Emitting Diodes [ 下載 PDF ]

Yan-Kuin Su, Jian-Jhong Chen

In this article, we review and discuss our important researches and technologies of light-emitting diodes (LEDs) including the improvement of the internal quantum efficiency, the improvement of the light extraction efficiency, and white LEDs. In the future, some technologies still can be well developed to make more contributions.

NMR and Synchrotron Light Source in Life Sciences Research [ 下載 PDF ]

Wen-guey Wu

Biomedical research and pharmaceutical industry rely heavily on powerful core facilities such as X-ray, NMR and neutron source for structural determination of biological macromolecules and machinery. Herein, we review the technical and infrastructural development of the structural biology platform in Taiwan during the last 20 years to suggest that current European integrative research infrastructure in Grenoble may be a good model for the future converting of Hsinchu Industrial park into high tech oriented innovation campus.

Generation and Applications of Structured Beams by Use of Miniature Solid-State Lasers [ 下載 PDF ]

Ting-Hua Lu, Yung-Fu Chen

Recently, generation and applications of structured beam have attracted much attention in optical researches. In this work, we introduce the structured beams localized on geometrical rays generated from advanced laser system. Furthermore, the correspondence between optics and mechanics provides some insights into the study of quantumclassical correspondence. Besides, the structured beams can be converted to possess optical angular momentum by a pair of cylindrical lens. The structured beams possessing large orbital angular momentum play an important role in manipulating microparticales.

Structural Biology—A Powerful Tool for the Modern Life Science Research [ 下載 PDF ]

Shan-Ho Chou

I will discuss in this article how the progress of structural biology has revolutionized the research of modern life science. The life science research has been transformed a great deal from a classical, macro-scale biology to a micro-scale, molecular biology to the now nano-scale structural biology. I will also talk how these developments have enabled us to investigate deeply into the mystery of the modern life science from a series of results in our recent studies in microbial structural genomics. I shall also discuss the significant impact of the national synchrotron core facility on research in Taiwan.

From Microscopy to Nanoscopy [ 下載 PDF ]

Po-Yen Lin, Yi-Cheng Lin, Hong-Chou Lyu, Fu-Jen Kao

Optical microscopy has been widely applied in numerous disciplines, especially in biological science due to its noninvasiveness, high contrast, and high sensitivity for in vivo imaging. However, the diffraction limit of the farfield light microscopy, as predicted by Abbe's theory (two objects cannot be resolved when they are separated by less than half of the incident light wavelength), has plagued the achievable spatial resolution for over a century. In recent years, the novel advances in optical microscopy, such as photoactivated localization microscopy (PALM), stochastic optical reconstruction microscopy (STORM), stimulated emission depletion (STED), and saturated structured illumination microscopy (SSIM) have, nonetheless, surpassed optical microscopy resolution limit beyond the Abbe's barrier. These advancements will bring unprecedented impact to the future development of critical bioand nano-technologies.

Sensors Integration Using CMOS MEMS Platform [ 下載 PDF ]

Weileun Fang, Chih-Ming Sun, Ming-Han Tsai, Yu-Chia Liu

The authors have reported the design and implementation of CMOS MEMS accelerometer in Instruments Today (August, 2008). In this article, the authors would like to further introduce the concept of CMOS MEMS fabrication platform. The design and fabrication of various micro sensors, including tri-axis accelerometer, temperature sensor, pressure sensor and tactile sensor, is discussed. Moreover, the monolithic integration of these micro sensors on a single chip is also available using the present CMOS MEMS platform. In application, the sensors implemented by the author's research group in the Micro-Device Lab., National Tsing Hua University are demonstrated. These sensors are fabricated using the TSMC 0.35 µm standard CMOS process plus the post-CMOS integration platform developed by authors.

Technical Challenge of LED Solid State Lighting [ 下載 PDF ]

Ching-Cherng Sun

In this paper, we discuss the development trend and the possible bottleneck of LED solid-state lighting. In the LED chip level, how to maintain the internal quantum efficiency under high current injection is a big challenge for the material engineering. In the package level, the quality in optical, color, electrical and thermal managements are related to the performance in LED lighting. In the optical technique, we introduce the concept of four-level optical design and discuss its role in chip, package, module and fixture levels, respectively. Besides, we also discuss the importance of human factor engineering to the LED lighting.

Applications of Microarray in Aptamer Study [ 下載 PDF ]

Yeh-Hsing Lao, Lin-Chi Chen, Yi-Chung Chang, Chun-Wei Chi, Konan Peck

'Aptamers' are a unique class of single-stranded oligonucleotides that resemble naturally occurring antibodies. They can fold into unique tertiary conformations for specific recognition of target proteins. Thus, aptamers have great potential for disease diagnosis and therapy. Generation of an aptamer relies on an in vitro selection process called SELEX, which involves analysis and identification of ligands from a multitude of nucleic acid sequences. Hence, exploitation of microarray techniques can effectively shorten the time required for aptamer screening. In addition, arraying oligonucleotide-based aptamers into a microarray format can lead to a novel protein chip application. Considering the aforementioned reasons, we brief the backgrounds for aptamer R&Ds and discuss the strengths of microarray techniques in acceleration of aptamer screening and protein analysis by several practical examples in this article.

Application of Dielectrophoresis Chip Integrated with Raman Spectroscopy for Rapid Identification of Microorganisms [ 下載 PDF ]

Chi-Chang Lin, Hsien-Chang Chang

Microorganisms normally exist in the natural environment with different population and nutrient uptake methods under the balanced ecological systems. However, bacteria might pollute our food or water easily owing to it's over growth under the muggy and humid environment. While human beings, animals or even plants are incidentally infected by pathogenic microorganisms, their endangerments to individual and public health are often shocking. In order to prevent and avoid these disasters, it is a great urgency to develop novel culture and label free sensing technologies with rapid detection and identification functions. A novel 3D bio-diagnostic microfluidic chip with continuous bacteria sorting and concentrating functions by dielectrophoresis and in situ bacteria surface enhanced Raman scattering analysis is presented.

Taiwan Ultra High-Field Solution NMR Core Facility and Applications in Genomic Medicine [ 下載 PDF ]

Tai-huang Huang, Chi-Fon Chang, Wen-Jin Wu

NMR spectroscopy is perhaps the most versatile and most important physical technique. Its applications encompass material characterization, chemical structure determination, metabolism, biomacromolecular structure dynamics and function, and MRI etc. It has become an indispensible advanced tool in biomedicine, natural science, and engineering. Here we briefly introduce the recent developments in ultra high-field solution NMR at the High Field NMR Center (HFNMRC) at Academia Sinica. HFNMRC is open to all qualified users from academic and industry alike in Taiwan.

The Rapid Progress of MRI—A Glance over 36 Years [ 下載 PDF ]

Ching-Nien Chen, Lou-sing Kan

Magnetic resonance imaging (MRI) is a non-invasive imaging method which does not involve radiation. Unlike other imaging modalities which are restricted by the shape and geometry of the human body and the instruments, MRI can achieve any desired orientation of sectional views. The research and development efforts put in this field over more than three decades have proven that the invaluable wealth of information derived from MRI far compensated for its cost. It is now a widely accepted and trusted diagnostic modality and is trotting on its way to the field of preventive medical practice. Here we give, in layman's language, a brief introduction about its basic principles, major components, magnetic field, probes, and how it differs from X-ray CT and ultrasound devices. The article is targeted to the general public.

Progress in Compound-Specific Isotopic Ratio Mass Spectrometry Development: Forensic Identification of Adulterated Wines [ 下載 PDF ]

Yong-Chien Ling, Yu-Jie Yuan, Pei-Yi Tsai, Jenn-Ru Shao

This research exploits that the isotopic ratio of natural materials is different dictated by their effects by feed, process, and environment. Plants are classified into C₃, C₄, and CAM plant depending on their photosynthetic pathway. Plant sugars thus possessing different carbon isotopic ratio. Alcohols fragmented from sugars also possess different carbon isotopic ratio. Based on this principle, we have developed a compound specific isotope analysis (CSIA) method using gas chromatograph-isotope ratio mass spectrometer (GC-IRMS) for forensic identification of adulterated wines and applied to 100 brands of wine. Our results demonstrate that by exploiting the unique isotopic property of composing elements it is possible to differentiate organic compounds with similar molecular composition. The CSIA method could compensate the deficiency of molecular-composition base gas chromatograph mass spectrometry.