Aim for the Top University Project
National Central University – " Optics and Optoelectronics "
Principal Investigator: CHYI, Jen-Inn
I. Analysis and Evaluation of the Key Field
(1) Current Achievements and Features
With the support of the Ministry of Education “Aim for the Top University” (ATU) project,
the optics and optoelectronics team at National Central University (NCU) has gained significant
research momentum and has produced numerous important results that are highly regarded in
national and international academia and industry. Over the past five years, team members have
published 440 SCI journal papers, filed 110 patents (47 granted to date). Two members are
recognized as both OSA and SPIE Fellows, another member elected as both an IEEE and SPIE
Fellow, and Prof. C.-C. Lee is the elected chair of the 2011 Fellow Committee of SPIE. Four
members have been awarded the Distinguished Research Award and two members awarded
Outstanding Technology Transfer Awards both by the National Science Council. Three members
have received the Industry Contribution Award from the Ministry of Economic Affairs. Team
members have also actively served as editors, associate editors, and guest editors for several
internationally renowned journals, such as IEEE Photonics Technology Letters, Japanese
Journal of Applied Physics, IEEE Proceedings, Applied Optics, and Journal of Holography and
Speckle. In addition, we emphasize industry-academia collaborations, which have resulted in 61
joint projects with NT$47 million funding, more than 15 technology transfer cases with incomes
of more than NT$23 million, and two spin-off companies in the past 5 years.
(2) Current Leadership Status in Taiwan and Internationally
The accomplishments of the optics and optoelectronics team have underlined its leading
role in several areas, such as light-emitting diode (LED) solid-state lighting, optical science and
engineering, semiconductor quantum dot single-electron transistors/single-photon sources, and
high-speed photodetectors. We published the first precise optical model of LED lighting in
Optics Letters in 2006, and since then it has been extensively used in Taiwan industry, enabling
Taiwan lighting industry to lead the world in optical design capability for LED lighting.
Technology of precise simulation in light extraction efficiency for three major LED packages
and the first phosphor model for white LEDs have also been developed. In optical science and
engineering, the technologies of ion-beam sputtering deposition, ion-beam assisted deposition,
and magnetron sputtering deposition that were developed in the Thin Film Technology Center
(TFTC) make the center a world leader in its field.. The group developed a state-of-the-art
anti-vibration optical admittance monitoring and testing system based on a dynamic polarization
interferometer. It is a powerful and full-field monitoring system for precision thin-film coatings.
Moreover, a low-cost coating method for 193-nm DUV optics, very essential to current Si
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industry applications, was developed and published in Optics Express. In the area of
optical-testing instrumentation, the group developed an alternative to using a
computer-generated hologram (CGH) for optical elements testing; specifically, a high-speed
aspherical interferometer based on the geometrical nulling principle was developed. This
approach significantly increased the measurement yield speed. The THTC also developed two
types of stress measurement devices that can be used in precision laser components and thin
films on flexible-substrates. In the semiconductor quantum dot area, we demonstrated
room-temperature operation of Ge single-electron transistors with a high Coulomb oscillation
peak-to-valley ratio>750. We are the first team to place one to two QDs in the photonic crystal
nanocavity and thereby make the first single-photon Source in Taiwan. The light source has a
coupling efficiency of 92%, purity of 99%, and polarization of 95%. This work has been cited
more than 100 times since its publication in Physical Review Letters. As for high-speed
photodetectors, we demonstrated a photodetector with a record-high saturation current
bandwidth product (7500 mA-GHz). This record is 3-fold higher than previously reported values
by NTT and the University of Texas at Austin. Another noteworthy achievement is the recent
realization of a 10 Gbit/s photodetector with zero static power consumption. In Dye-sensitized
Solar Cell (DSC) research, we have developed a new dye that gives the highest efficiency in the
world. The proposed design guideline has been extensively used worldwide. Due to the support
of the MOE ATU program, the research team has become a frontrunner in both the nation and
the world in the area of optics and optoelectronics of interest.
(3) Important Contributions to Industry and the Social Development of the Country
The achievements of this project in the past five years have not only boosted our research
level and worldwide visibility, but also significantly contributed to industrial technology
developments in this country. Three of our team members have been awarded the Industrial
Contribution Award by the Ministry of Economic Affairs in Taiwan, a recognition that is
unparalleled nationwide. Two of the team members were awarded Outstanding Technology
Transfer Award by National Science Council, making NCU acclaimed by National Science
Council as the Outstanding Technology Transfer Center in 2009 and 2010 consecutively.
Moreover, more than 100 patents have been filed and 15 technology transfer agreements have
been signed with a combined return of more than N$23 million. Transferred technologies
include high-speed photodetectors, advanced semiconductor processing technologies,
LED/solid-state lighting technologies, coater designs, multi-layer thin-film optical monitoring
technologies, solar cell processes, color engineering technologies, and thin-film coating
technologies. With these endeavors, two spin-off companies from the research team have also
been founded. National Central University established the Taiwan Green Lighting Industrial
Research & Development Service Center in 2009 to facilitate collaborations between academia
and industry. Technology transfer agreements worth more than NT$30 million have been signed
since the inception of his Center. NCU has also hosted the LED Solid-State Lighting Conference
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on a yearly basis since 2006.
This conference has become one of the most prestigious
conferences in the country, which has had more than 2000 attendees over the past 4 years. To
facilitate tool development for the solar cell industry, workshops on solar cell process tools have
been held jointly by the Metal Industry Research and Development Center and National Central
University. More than 400 people have attended these workshops over the past 2 years. Team
members are heavily involved in coordinating and executing national projects, such as the
National Program of Science and Technology-Energy and Green Energy Industry Promotion
Initiative.
In addition, Professor C.-C. Lee has been instrumental in the internationalization of
Taiwan’s optical engineering community. In the years of 2007, 2008, and 2010, while served as
convener of the National Science Council and president of the Taiwan Photonics Society, he
transformed the annual conference on Optics and Photonics in Taiwan (OPT) from a domestic
event to an international one. Furthermore, he was designated by Optical Society of America
(OSA) as the co-organizer of the 2011 international OPT. These endeavors have considerably
boosted the international visibility of Taiwan’s optical engineering research, and bridged the
international community and inland researchers.
(4) The Major Differences or Breakthroughs enabled by the previous phase of “Plan for
Developing Top Universities and Research Centers”
The facilities established under the first phase of this Plan have significantly enhanced our
research strength and propelled our achievements in several subjects. For example, the test
instruments established for LED processing, characterization, packaging, and reliability tests
have allowed the LED team to demonstrate several innovative ideas, including the first LED
light model and a high-precision phosphor model. Using the e-beam lithography system
procured, we were able to demonstrate the high-performance room-temperature operation of Ge
quantum dot single-electron transistors, which have won us a National Program of Science and
Technology-Nano Project for two consecutive terms. In addition, the Sb cracker installed in the
molecular beam epitaxy (MBE) machine created a new research field for advanced electronic
devices and circuits and earned us a long-term project with TSMC. Furthermore, we have
established the best high-frequency measurement laboratory in Taiwan. This laboratory houses a
DC to 170 GHz millimeter-wave network analyzer, a 40 Gbit/sec signal quality analyzer, a 67
GHz optical network analyzer, a 50 GHz sampling scope, and a laser heterodyne beating
measurement system from near DC to several THz. With these instruments, we have achieved
several world records for photodetectors, such as photodetectors with the highest saturation
current-bandwidth product (100 GHz, 75 mA, 7500 mA-GHz), avalanche photodiodes with the
highest gain-bandwidth product (~700 GHz), and photonic-wireless transmission systems with
the highest data rate (20 Gbit/sec). Between 2006 and 2010, team members presented 16 papers
at the most prestigious conferences, Optical Fiber Communication (OFC), and were invited to
join the technical program committee.
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(5) Description of the Current Status of the Existing Resources in the Research Center and
Allocation of All Funding Sources
The research fund received in the first phase of this Plan was mainly used to purchase
major equipment for subprojects as well as common facilities, which have enabled our team
members to access an increased amount of external funds. From 2006 to 2009, we have won
around NT$90 million, 100 million, 150 million, and 137 million in research funds, respectively,
from outside funding agencies. These include three Ministry of Economic Affairs projects, three
NSC nano projects, and the Plan for Promoting Academic Excellence of Universities phase II. A
well-equipped micro-optoelectronics laboratory for semiconductor processes could thus be
established and maintained. This laboratory is currently used by 20 faculty members and about
150 graduate students. Major facilities in this laboratory include two e-beam writers, two
PECVD, four dry etchers, etc. Other equipment, such as MOCVD, excimer laser, ECRCVD, an
LED lighting characterization system, and a high-frequency measurement system, have been
procured and located in specific laboratories for better utilization. There is another important
common facility for next generation photovoltaic research being built in NCU with a financial
support of about 5 million USD from National Science Council. The only one of this kind
laboratory in Taiwan aims to (a) conduct research and development in die- sensitized (DSC) and
organic photovoltaic (OPV) solar cells, (b) establish internationally certified instruments and
standards for measurements, and (c) provide services for device fabrication and characterization.
It is expected to be a major DSC and OPV research laboratory in Taiwan as well as in the world.
(6) Analyses of the Current Statuses of Research Centers in the Same Field and Plans for
Future Development for the Research Center
The Optics and Optoelectronics team at NCU has established its unique standing among
comparable centers in the nation in several areas, which include LED lighting technologies,
high-speed optoelectronic devices, microwave circuits, quantum dot single-photon sources,
single-electron transistors, optical design, color science, optical-testing instrumentation, and
optical thin-film technologies. The high-speed optoelectronic devices and microwave circuits
group has generated world-leading device performance. The research in nanophotonics, i.e.
quantum-dot nano-lasers, single-photon sources and single-electron transistors, is exceptional in
Taiwan and among the best in the world. In addition, the Thin-Film Technology Center at NCU
is the only one of its kind in Taiwan. We will continue our efforts in both advanced and applied
research in the second phase of this program. Our goal is to become a world-class research
center in the fields of solid-state lighting, optical science and engineering, nanophotonics,
high-speed energy-efficient devices, and energy harvesting devices.
Based on the foundation established in the previous phase, our activities in the next phase
include recruiting talented faculty, strengthening collaborations between academia and industry,
promoting international collaborations, increasing our international visibility, and enhancing the
strength of the current research areas.
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(7) Current Status of Cooperation or Integration with Research Centers in the Same Field
from Other Universities or Countries and Benefits after Integration
Members of the Optics and Optoelectronics team have collaborations either in progress or
in the preparatory stage with many domestic and foreign institutions. For example, the
solid-state lighting group is collaborating on human factors and illumination efficiency with the
LAPLACE laboratory directed by Prof. G. Zissis of Toulouse III University, France. The same
group also cooperates with Prof. L. Halonenn of Aalto University of Finland in optical design
and human factors illumination research. To help Taiwan industry in developing high technology
for LED lighting, the solid-state lighting group established the Taiwan Green Lighting Industrial
Research & Development Service Center at NCU, which is comparable to the Lighting Research
Center of Rensselaer Polytechnic Institute in the USA. The Center is also working with Bayer
(Germany) in setting up her first Taiwan R&D laboratory in NCU campus with special interest
in optical films for lighting applications. Other collaborations are with the Electronics &
Optoelectronics Research Laboratories of ITRI and the California Institute of Technology in
germanium quantum dot; NTU Center for Condensed Matter Science in GaN nano-rod single
photon emitters; NCTU and NTHU in high-speed lightwave communication devices, circuits,
modules and systems under a few integrated projects of National Science Council and Ministry
of Economic Affairs; and the Research Center for Applied Science of Academia Sinica in
quantum dot physics and devices. In the field of optical science and engineering, we have
successful collaborations with the College of Optical Science of the University of Arizona in
optical design, optical testing, and optical thin-film monitoring. There are also collaborations
with University of Paris 13 and Ecole Centrale Marseille, University Aix-Marseille III on optical
thin-film-related technology and a joint research center at NCU is under preparation.
The four universities in the University System of Taiwan (UST), namely National Central
University, National Chiao Tung University, National Tsing Hua University, and National
Yang-Ming University, have created their own specific leadership in both research and
education in photonics. A great effort has been made to integrate the expertise and resource in
the photonics research among the four institutions in the second phase of the ATU program,
aiming at a world leading Research Center in optics and photonics. We have already several
successful collaborations with NCTU, such as volume holography, high-speed transistors, novel
quantum dots, and microwave photonics. Based on the solid foundations laid earlier, the NCU
optics and photonics team has decided to extend the collaborations and participated in forming
an Advanced Photonics Research Center with the other three universities (NCTU, NTHU, and
NYMU) in the University System of Taiwan (UST). Six major research areas, namely
Nano-photonics technology and devices, Communication and information technology, Display
and image technology, Laser and quantum optics, Optical engineering and energy technology,
and Bio-photonics and molecule imaging technology are have been planned for this Center. The
entire NCU team will seamlessly join the UST Center according to the designated disciplines
and leverage the resources in this center to be more competitive in the international academia.
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(8) Plans for Integrating Resources from Research Centers to achieve the Aim for the Top
University
The optics and photonics team consists of faculty members and graduate students from
various academic units, including Optical Sciences Center, Thin Film Technology Center,
Electrical Engineering, Optics and Phonics, Physics, Mechanical Engineering, Chemistry and
Chemical Engineering. This integrated team is known to be well organized and collaborative
over the years. Research subjects in system or interdisciplinary levels can be carried out by this
team. In addition, a significant portion of the resources received from this project will be
invested on the construction and operation of large scale common research facilities. With well
equipped infrastructures, NCU is able to recruit more talents, raise research momentum and help
faculty members to win more external contracts from both governmental and private sectors.
The international collaborations, hosting conferences, and visiting activities undertaken in this
project will also greatly facilitate the internationalization of NCU.
II. Project Content
We will explore and investigate research topics in the fields of optics and optoelectronics
technologies that align with national interests and worldwide trends. In the next five years, this
interdisciplinary team will apply their specialties in the fields of optics, electronics, mechanics,
and biomedical engineering, to develop technologies for energy efficiency and carbon reduction,
achieving academic excellence and increasing industry competence. The proposed five research
projects are described as follows:
(1) Component 1: LED Solid-State Lighting Technology
(Project Investigator: SUN, Ching-Cherng)
Due to the trend of eco-awareness, energy conservation and environmental protection have
become one of the most important global issues. Therefore, methods for reducing energy waste
and preventing pollution are consistently top priorities. Successful development of GaN material
for high-power LEDs in the early 90’s has made LED not only a light source for signage and
indicator but also for general lighting. LED technology provides the advantages of compact size,
long life, fast response, high reliability, robustness, high efficiency and mercury-free product,
which enable it to be the most important light source in the 21st century.
In the past, SSL research has been focused primarily on improving luminous efficacy.
Because less work is done on human factors, the effects of LED optical properties, light patterns,
color performance, and glare have not comprehensively addressed. In the next decade,
simultaneous improvements in luminous efficacy and reliability will remain an important topic
in SSL research. Efficacy and reliability depend on technical developments in materials
engineering, micro-processing, optical simulation and thermal management. In this project, we
will focus on human factors related to LED-based lighting technology and bio/agricultural
applications with high luminous efficacy and high reliability solutions. The proposed research
topics are described below.
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1. High-efficiency LED package technology: to develop key technologies for high-efficiency
high-reliability LED packaging, including metal bonding, high-quality substrate, thermal
measurement and management. The targeted efficacy for high-efficiency luminaries is
150 lm/W at 6 W, and for high-CRI white-light LEDs (Ra>92) is 150 lm/W at 1 W.
2. LED color technology: to develop the optimized phosphor recipe for a high-color
rendering index; to develop color mixing technology based on electronic control
techniques for natural and comfortable lighting environments.
3. Automotive and projection technology: to develop an optical design for Economic
Commission for Europe (ECE) forward lighting with 65% energy savings; to optimize
an optical cavity to achieve a 130% enhancement ratio in directionality of LED light
projection.
4. LED lighting technology based on human factors: to develop an evaluation technique
based on a precise human eye model; to develop dynamic anti-glare technology.
5. LED lighting applied to bio and agriculture: to study lighting effects on human skin and
other health problems; to develop lighting technology to prevent agricultural plant
disease.
(2) Component 2: Physics and Applications of Semiconductor Quantum Dots
(Project Investigator: HSU, Tzu-Min)
Providing a sustainable and efficient energy supply is a major global issue under intensive
investigations. Solar power, which uses sunlight to generate electricity, is a promising clean and
renewable energy source. Unfortunately, current solar energy conversion technologies are
extremely inefficient; excess solar energy is lost as heat. Thermoelectric (TE) materials provide
a way to directly convert heat into electricity and are also capable of acting as solid state
refrigerators or heat pumps. Still, TE devices are not commonly used due to their low
conversion efficiency. A good TE material would have high electrical conductivities, high
Seebeck coefficients, and low thermal conductivities. However, maximizing the figure of merit
(ZT) of TEs is challenging because optimizing one physical parameter often adversely affects
another. Encouragingly, low dimensional structures have been theoretically predicted and
experimentally proven to be able to enhance electrical transport properties and decrease thermal
conductivity simultaneously. SiGe-based nanostructures are an attractive and promising TE
material system due to their superior electrical transport properties and bandgap engineering
flexibilities. We have been supported by the National Science and Technology Program for
Nanoscience and Nanotechnology to study high-temperature Ge QD single electron transistors
(SETs) and Ge QD functional optoelectronic devices. A simple, low-cost, and IC-compatible
process for forming SiGe QDs in a self-organized manner using selective oxidation of a
SiGe/Si-on-insulator (SGOI) has been developed. With the insights into the carrier transport in
Ge QDs/SiO2 system that were gained previously, we have a solid foundation to explore the
feasibility of efficient thin-film-like SiGe nanostructures microcoolers.
Beside, semiconductor quantum dots have the properties of three-dimensional
confinement and δ-function density of states, which means that they are considered a highly
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suitable material for quantum light sources such as quantum dot lasers and single-photon
sources. However, in quantum dot systems, extraction efficiency is rather low due to internal
total reflection as the quantum dots are embedded in the semiconductor matrix. This requires an
optical cavity to improve the efficiency of quantum dot emission. Among the optical cavities
available, photonic crystal nanocavity (PCN) has a high quality factor and an extremely small
mode volume (~10-2 m3), which is able to improve both the extraction efficiency and
spontaneous emission rate of quantum dot emissions. In this research, we aim to investigate
coupled PCNs and realize electrically driven PCN quantum dot light sources. The proposed
research subjects are described as follows:
1. High-efficiency Si1-xGex quantum dot (QD)/oxynitride thermoelectric (TE) devices: to
explore the feasibility and fundamental physics of Si1-xGex TE nanostructures and
microcoolers; to develop (a) bulk fabrication processes for high-efficiency TE Si1-xGex
nanostructures (such as QDs, nanowires, and superlattices) in an SiO2 or Si3N4 matrix and
pn-coupled microcoolers; (b) measurement technology to effectively characterize the TE
properties of Si/Ge nanostructures; and (c) fundamental TE physics of low-dimensional
systems.
2. Novel QD-coupled photonic-crystal-cavity and electrically driven photonic-crystal-cavity
light sources: to study the coupling effects between quantum dots and coupled
photonic-crystal-cavities; to develop coupled-cavity quantum dot lasers, electrically driven
photonic-crystal-cavity quantum dot lasers and single-photon sources.
(3) Component 3: Millimeter-Wave Optoelectronic Devices and Bio-Imaging System
(Project Investigator: CHIOU, Hwann-Kaeo)
Millimeter-wave frequency bands have been used in many applications for both civilian
and scientific purposes, such as satellite communications, radio astronomy, weather radars,
automotive radars, and others. The recently explored millimeter-wave and THz frequency bands,
located between microwave and far-infrared regimes, are of particular interest. Signals at these
frequencies can penetrate papers and clothes and interact with metallic and bio-substances, and
therefore can be used to detect weapons and contrabands that are hidden under clothes. Through
their rotation and vibration modes, bio-molecules can be directly identified by millimeter waves
without additional labeling processes. Unlike X-rays, millimeter-wave radiations are low energy
non-ionizing sources that are relatively safe to humans. As a result, millimeter-wave imaging
has become one of the most pursued technologies for bio-molecules imaging and sensing.
In this project, antimonide-based III-V heterostructures will be developed for high-speed
low-power devices, including HFETs, HBTs, and photodiodes. In addition, ferroelectric and
ferrite thin films will be developed to implement novel multifunctional high-frequency passive
components. Based on the aforementioned devices and components, we plan to realize a
low-power millimeter-wave optical phased-array sensor system, which uses phased-array
transceiver architecture to focus millimeter-wave beam, thus increasing the resolution of
biomedical images. The applications for low-power phased-array systems are versatile,
including wideband communications for digital home use (60 GHz), anti-collision automotive
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radars (77 GHz), radio astronomy (30 GHz - 1 THz), bio-imaging and spectroscopy, and so on.
In this sub-project, we will focus on advanced biomedical sensing/imaging applications. Major
research topics are briefly described as follows.
1. Antimonide-based nanoscale transistors for low-power high-speed ICs: to characterize
InGaSb and InAsSb n/p-channel two-dimensional electron/hole gas; to fabricate deep
submicron field effect transistors for high-speed and low-power devices and circuits.
2. Ferroic thin films and their multifunctional passive components: to build a pulsed-laser
deposition system for ferroelectric (Ba1-xSrxTiO3) and ferrite (BaFe12O19) thin films; to
fabricate various high-quality factor ferroic components, such as varactors, phase shifters,
tunable filters, nonlinear transmission lines, and circulators.
3. Optoelectronic-generated wideband submillimeter-wave signal sources for biomaterial
measurements: to develop a W band (75-110 GHz) and D band (110-170 GHz) optical array
transmitter for 3D medical image system.
(4) Component 4: Novel Thin Film Solar Cells
(Project Investigator: CHANG, Jeng-Yang)
According to a recent report from the German Advisory Council on Global Change
(WBGU), 60% of the total energy required by human must come from solar energy by 2100.
The main barrier to widespread implementation of solar cell system is the cost of ownership. To
decrease the cost of solar cells, overall efficiency must be increased while manufacturing costs
must be cut. The balance between the two has to be pursued. Among the various types of solar
cells to date, Si-based thin film solar cell has the potential to meet the ultimate requirements
because of the abundance of silicon and the stability of silicon. In addition, the equipment and
processes for Si thin film solar cells are relatively well established. Currently, the efficiency of
silicon-based thin film solar cells is still far from what is requested. These silicon-based thin
film solar cells are prepared mainly by PECVD. Its deposition rate is too low (~0.2 nm/s) and
multilayer nanocrystalline layer is difficult to realized. Compared to PECVD, ECR-CVD
process utilizes a lower temperature as well as a 1000-fold higher ion concentration for free
radical reaction. In this project, we will develop novel high-efficiency silicon-based solar cells
utilizing a high deposition rate ECR-CVD system developed in house with industry.
Dye-sensitized solar cells (DSCs) have recently emerged as a promising candidate for
photovoltaic technology in virtue of the high efficiency and low manufacture cost. DSC with
efficiency higher than 7 % was first demonstrated in 1991 by Grätzel et al. using ruthenium (II)
complex as a photosensitizer. Since then, the potential of DSC has been recognized and it has
become an appealing candidate as the next generation photovoltaic device due to its high
efficiency, full color, great flexibility, and low cost. The subjects to pursue in this project are
listed as follows:
1. Silicon-based thin film solar cells
a. High-efficiency Si-based thin film solar cells: to develop a high-deposition rate electron
cyclotron resonance chemical vapor deposition (ECRCVD) system for a-Si, nC-Si, μC-Si
grading/multiple layer solar cells; to investigate the optical and electrical properties and
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growth mechanism of each layer so as to reduce interface defects and enhance light trapping
for higher efficiency.
b. High-efficiency heterojunction with intrinsic thin layer (HIT) solar cells and processes: to
investigate low-oxygen content Czochralski wafers for high-efficiency low light-soaking
degradation HIT solar cells; to optimize interfaces for higher efficiency.
c. Solar cell light trapping technology: to use guided-mode resonance (GMR) and leaked-mode
resonance coupling effects to enhance the near infrared and visible light absorption in Si film
to increase its efficiency; to use the surface plasma resonance (SPR) effect to extend the light
absorption spectrum of solar cells.
d. Advanced novel silicon-based solar cells: to explore quantum dots and nano particle
silicon-based solar cells.
2. Organic thin film solar cells
a. Dye: use Ru complexes as a base and extend its conjugate length of the ancillary ligand, to
effectively increase its optical absorption and red shift its absorption position, and in which
hole and electron can be more effectively separated in dye molecule. In addition, develop
Squaraines as a base unit to enhance far infrared and near infrared absorption.
b. Flexible organic solar cells: The advantages of the flexible devices are low cost (can be made
role-to-role), easy to fit into any structure, can be used as a portable energy source.
Nevertheless, flexible device use low temperature process, therefore the bottle neck is how to
make continuous TiO2 film at low temperature (<160 oC). For more practical usage,
creating a low volatile ionic liquid electrolyte (high stability) is also the effort for developing
high efficiency flexible dye-sensitized solar cells.
c. Solid state DSSC: combine the developing dye in this program, with combination with porous
TiO2 system, choose adequate hole transport material, optimize process conditions to
fabricate high efficiency solid state DSC.
(5) Component 5: Hyperspectral 4-Dimensional Free-Form-Optics System
(Project Investigator: LEE, Cheng-Chung)
Incessant, rapid developments in optical science and engineering have led to substantial
progress in different scientific realms. For example, the success of the Hubble Space Telescope,
whose design is based on optical science, made a variety of profound and continuous impacts on
physics and astronomy. Similarly, developments in thin-film technology have substantially
changed the human lifestyle by contributing to applications like thin-film displays, thin-film
solar cells, LED lights, optical communication, laser components, gravitational wave detection,
and others in the last decade. They are expected still to do so in the future. Hyperspectral
imaging systems can obtain spatial and frequency domain information simultaneously and have
been mainly utilized for military, environmental, and geological research. It has also been
gradually applied to medical research in recent years; in particular, serves as a non-invasive
method for early cancer diagnosis, which is expected to become one of the most important
optical technologies in the near future. Therefore, this subproject will integrate research teams
from the Department of Optics and Photonics, the Thin-Film Technology Center, the Optical
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Sciences Center, and other related institutes at NCU to develop a four-dimensional hyperspectral
free-form optical system, which involves interdisciplinary efforts, including the
newly-developed mathematical description of free-form surfaces, advanced detection
technologies, optical thin-film technologies for wideband and high-accuracy applications. This
project will emphasize both advanced academic research and industry collaboration. Based on
NCU’s full-fledged research capabilities and achievements, including optical design, optical
fabrication, optical detection, and optical/photonic systems and applications, we expect to
contribute greatly to the optics and photonics industry in Taiwan. The research topics covered in
this effort are listed below.
1. Free-Form Optics: In optical design, free-form optics can be used to replace one or more
traditional spherical optical components and increase overall optical system performance
while reducing the number of required components and the system weight. This research
aims to develop three key solutions to practical implementation problems associated with
free-form optics in optical systems: the Forbes Polynomials model of free-form optics,
optical testing of free-form optics, and the integration between precision manufacturing and
testing.
2. Advanced Optical Coating Technique: The purpose of this sub-project is to develop the
advanced optical coatings and techniques that are applicable to the hyperspectral,
four-dimensional optical system. The main tasks include development of an anti-vibration
optical admittance monitoring and testing system to obtain the reflection coefficient, optical
admittance, refractive index, and thickness of the film; the improvement of coating
uniformity and stability on the free-form optical components; minimization of the stresses on
the surface of the free-form optical components; and research on the ultra-wide working
wavelength range optical beam splitters for the hyperspectral, four-dimensional optical
system.
3. Hyperspectral Four-Dimensional Optical Imaging System: In this sub-project, excitation light
sources ranging from ultraviolet to infrared will be built. Combined with free-form optics and
novel optical coating techniques, a hyperspectral optical imaging system with
diffraction-limited spatial resolution will be developed. By replacing the conventional
spherical lenses with a single free-form lens, the imaging system can be further miniaturized.
This optical imaging system will be used for various cross-disciplinary researches, including
biomedical- biomedical molecular imaging and clinical (ex. cancer) diagnosis and treatment,
and material science- structural reconstruction of paleontological fossils, material properties
study and device characterization.
III. Overall and Annual Objectives
(1) Overall Objectives
We will extend the industry-academia collaboration, recruit outstanding talent, increase
international cooperation, and renew our research facilities to become a leading optoelectronics
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research center in the areas of solid-state lighting, nano-photonics, lightwave communication
devices, compound semiconductor materials and devices, and optical engineering. In this phase,
we will develop high performance white LED light sources, high efficiency Ge quantum dot
thermoelectric micro-coolers, electrically driven coupled photonic crystal nano-cavity lasers, a
wideband (75-160 GHz) optoelectronic-based phased array imaging system, high efficiency
thin film solar cells, and a hyperspectral 4-dimensional imaging system.
(2) Annual Objectives
2011:
1. Simulation studies on the glare effects of LED luminaries based on a human-eye model,
including light-source sizes, CCT, brightness, etc.
2. Construction of a characterization system and theoretical modeling for low-dimensional
Si1-xGex/oxynitride thermoelectric materials
3. Construction of a pulsed-laser deposition system for ferroelectric (e.g. Ba1-xSrxTiO3) and
ferrite (e.g. BaFe12O19) thin films.
4. Development of a high-rate (>1.5 nm/sec) Si thin film solar cell deposition system and
achieve efficiency up to 8%.
5. Development of Ru complex dye for high efficiency (> 11%) DSC.
6. Development of an anti-vibration optical admittance monitoring and testing system with error
in refractive index <1%, and error in thickness <1%.
2012:
1. White-light LEDs with an efficacy of 120 lm/W at 6 W.
2. Fabrication of Ge QD/oxynitride/Si nanostructures with ZT approach 1.
3. Investigation of resonance modes of coupled photonic crystal nano-cavities.
4. Fabrication of antimonide-based n/p-channel heterostructure field-effect transistors (HFETs)
and the development of small-signal and large-signal models.
5. Development of GMR and SPR light-trapping technologies.
6. Development of DSC dye for near infrared range.
7. Development of free-form thin-film optics applicable to multiple spectral regions (mirror
reflectance > 95%, lens transmittance > 95%).
2013:
1. Production of white-light LEDs with an efficacy of 135 lm/W at 6 W and good
reliability test in +85oC~-40oC.
2. Fabrication of Ge QD/oxynitride/Si nanostructures with ZT larger than 1.
3. Design of antimonide-based BiFET (bipolar/field-effect transistor) microwave
circuits.
4. Development of a 67-125 GHz optoelectronic transmitter for 20-Gbps
point-to-point communications.
5. High-deposition rate silicon thin film solar cells with efficiency>12%, OPV with
>5%.
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long-term
integrated
error-free
efficiency
6. Free-form optics testing capability: measurement precision <1/20 waves (1 wavelength =
632.8 nm); Free-form thin-film coating technique with stress-induced thin-film deformation <
10 nm.
2014:
1. White-light LEDs with Ra>92 and efficacy of 150 lm/W at 1 W.
2. Fabrication of Ge QD/oxynitride/Si nanostructures with ZT larger than 2.
3. Fabrication of electrically driven photonic crystal nano-cavity lasers.
4. Development of reconfigurable front-end modules based on ferroic thin-film components and
antimonide devices
5. Fabrication of low-power consumption antimonide-based transistors with fT ≧500 GHz.
6. Development of low-light--soaking-degradation HIT solar cells and solid-state DSCs.
7. Dual-band (isolation >15dB) miniaturized probes with single free-form optical component
(ψ≦10 mm) for 4-dimensional optical system.
2015:
1. White-light LEDs with an efficacy of 150 lm/W at 6W.
2. High-efficiency Si1-xGex QDs/oxynitride thermoelectric microcoolers.
3. Electrically driven coupled photonic-crystal-cavity quantum dot lasers.
4. Demonstration of a wideband (75-160 GHz) optoelectronic-based array with
antimonide-based active devices and ferroic-based passive components for bio-molecule
imaging applications.
5. Development of silicon quantum dot solar cells and highly stable flexible DSCs.
6. Realization of a hyperspectral 4-dimensional imaging system for material testing, and clinical
diagnosis and treatment evaluation.
IV. Response and Improvements to Initial Review Opinions
Initial review opinion:
1.NCU has demonstrated very good achievements in the area of optics and photonics through
campus-wide collaborations led by her Optical Sciences Center. However, NCU is still a
smaller institution compared to the competitors. It would make NCU more productive and
outstanding if NCU could collaborate with NCTU through the University System of Taiwan
and receive complementary supports from NCTU’s strong areas, such as optical
communications, storage and display.
Response:
The comments are well taken. We have indeed undertaken several successful collaboration
efforts with NCTU, such as volume holography, high-speed transistors, novel quantum dots, and
microwave photonics. Based on the solid foundation already laid, the NCU optics and photonics
team has decided to extend this collaboration and participated in forming an Advanced
Photonics Research Center with the other three universities (NCTU, NTHU, and NYMU) in the
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University System of Taiwan (UST). Six major research areas, namely Nano-photonics
Technology and Devices, Communication and Information Technology, Display and Image
Technology, Laser and Quantum Optics, Optical Engineering and Energy Technology, and
Bio-photonics and Molecule Imaging Technology have been planned for this Center. The entire
NCU team will seamlessly join the UST Center according to the designated disciplines and
leverage the resources in this center to be more competitive in the international academia.
Initial review opinion:
2.The NCU optics and optoelectronics team has established unique capabilities in LED
technology, high speed optoelectronics devices, microwave circuits as well as classic optical
design, color science, modeling, and optical thin film technology. These unique capabilities
enable NCU team to be a leader in many important fields with significant industrial impacts
ranging from LED technology improvements with excellent optic and thermal packaging
designs to high speed optoelectronic devices and measurements. The NCU optical and photonic
team should continue to leverage the unique classical optics and high speed microwave and
optoelectronic devices to make significant research impacts to academic excellence and
industrial impacts. To be world class photonic center, you need to identify few unique and
irreplaceable strong field of excel1ence. NCU has these potential.
In NCU application write-up, there are information on their SCI papers, awards, international
cooperation and industria1 joint projects. The accomplishments are very good. To be even
renowned in the wor1d, NCU photonics team needs to focus on their uniqueness.
Response:
The comments are well taken. The NCU optics and photonics team will continue the strategy
of being collaborative and focused in our strong and unique areas with emphasis on academic
excellence and industry impact so as to gain more international recognitions.
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Website Link for the Full Version of the Aim for Top University
Project Proposal and Related Attachments
http://pine.cc.ncu.edu.tw/~ncutop/index.php?lang=2
Step 1：Login.
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Step 2：Login with user account：ncu7020
Password：ncu57025
Step 3：Select “Achievements & Future Plans”
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Step 4：Select 「The Aim for Top University Project Proposal」
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Step 5：Browse for the attachments of the project proposal of each key field.
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