Keynote Speeches

K1 - The electrical transport and luminescence mechanisms in ensembles of Si nanocrystallites

The understanding of the conduction mechanism and the optical luminescence in ensembles of Si quantum dots that are embedded in a dielectric matrix is still at a rudimentary level, in spite of the wide interest in the physics of Si nanostructures in the last two decades. In our work we tried to improve this understanding by deriving a self consistent and comprehensive framework for the discussion of the above properties and the relation between them. This trial was enabled by finding, in detail, the dependencies of the structural, the transport [1], the optical [2] and the charge storage [3] properties, on the density of these quantum dots, and interpreting these dependencies in terms of quantum confinement and percolation cluster statistics. Recently, following this understanding, we were able to fine-tune the above properties as well as to account for the out-of-equilibrium dynamics in these systems.

K2 - Optical studies of structural properties in SiGe nanocrystals and quantum dots

The importance of correlating structural and optical properties in technologically relevant materials and heterostructures is a two-way track: This knowledge should allow tayloring of specifically designed optical properties, and conversely, deducing structural characteristics using nondestructive optical probes. In this talk I will focus on characterization of Ge or SiGe nanocrystals and quantum dots. The mainly used optical techniques are spectroscopic ellipsometry and Raman scattering.

K3 - Tomographic Atom Probe potentials in Nano-scale Materials

The three dimensional Atom Probe (3D-AP) technique can be considered as the only technique which allows 3D imaging and chemical composition measurements capabilities at the atomic scale [1]. Since its early developments, 3D Atom Probe has provided major contributions in materials science.In order to enlarge the field of application to semiconductors and insulating samples, CAMECA has developed a new generation 3D Atom Probe in collaboration with the Atom Probe group from Rouen University, France. The main technical breakthrough of this instrument is the used of femtosecond LASER pulsing [2] instead of Voltage pulsing. Thanks to LASER pulsing, 3-dimensional atomic scale reconstruction for semi-conductors materials is now attainable. The second key advance is the development of a new large area Position Sensitive Detector (ADLD) with an original analog electronics and associated software reducing dead-times, allowing the detection of multiple ions arriving simultaneously[3]. The result is demonstrated superior quantification capabilities.The combination of LASER evaporation and a high accuracy position sensitive detector positioned at a short distance from the sample results in the analysis of “large” volumes (100nm area x few hundreds nm depth) with fast data rates in fully quantitative mode and high mass resolving power[4].The goal of this presentation will be to introduce the main features of the design of the CAMECA atom probe. Its analytical performances will be demonstrated by application examples selected from conductive and non-conductive materials within thin structures.

Session 1

A1-1 - The Progress of Semiconductor Non-Volatile Memory (半導體非揮發性記憶體之進展)

The rapid growth of digital media applications have pushed the NVM (non-volatile memory) to soar another highly demanding stage. Due to the traditional MOS device will face the physical limitation at 40 nm technology node, new material or new device structure will become necessity to explore in order to overcome such dilemma. In this talk, it will update the current development of NVM, including phase change memory and charging trapping memory. Meanwhile, it will also propose an extended technology based on the current reported technology to ensure the success for the next generation NVM.

A1-2 - Emerging Poly-Si Nanowires Devices (前瞻複晶矽奈米線元件)

First, we study the electrical characteristics of polysilicon thin-film transistors (poly-Si TFTs) of gate length 0.5 um with tri-gate nanowires and lightly-doped drain (LDD) structures. Among all investigated TFTs, the nano-scale TFT with ten 67 nm-wide split channels (M10) has superior and more uniform electrical characteristics than conventional single-channel TFTs. In addition, the ac and dc reliability of ten-nanowire poly-Si TFTs are investigated. In static and dynamic hot-carrier stress experiments, the ten-nanowire poly-Si TFTs reduces the degradation of Vth, SS, Ion, On/OFF ratio and DIBL, for all kind of frequency, rising time, falling time and temperature, compared to single-channel TFT. Second, a novel 4-mask pattern-dependent metal-induced lateral crystallization (PDMILC) polysilicon thin-film transistor (poly-Si TFT) was studied. The mobility and device performance of PDMILC TFTs improves as the each channel width decreasing. Furthermore, a SONOS Nanowire Poly-Si TFT Nonvolatile Memory was investigated. The most suitable transistors’ dimension, including the channel length, nanowire width, and oxide-nitride-oxide (ONO) dielectrics thickness were addressed. Consequently, the NVM programming/erasing and its two-bit operation mechanism will be study in detail. These emerging poly-Si nanowires devices are not only can be applied on SOP, but also on 3D CMOS stacked circuits.

A1-3 - HfOx based resistance random access memory (氧化鉿電阻式記憶體)

Resistive random access memories (RRAM) were considered to be the promising candidates as the replacement of flash memory in the next generation nonvolatile memory. Among these various resistive memories devices, there are two operation modes during the resistive switching. The voltage pulses can be of the same sign, the behavior is referred to as unipolar switching. The other is bipolar mode, which voltage of opposite signs are required to turn the devices on and off. In this presentation, nonstoichometric HfOx films prepared by atomic layer chemical vapor deposition were served as the insulator and TiN was adopted as the bottom electrode. By using Pt as top electrode, voltage induced unipolar resistive switching was repetitively found in the device of Pt/HfOx/TiN/Si with a resistance ratio > 10. During the cycles of switching, the power consumption for high and low resistance state were 0.25 and 0.15 mW. At 85 �aC, the memory device showed stable resistance switching and superior ability of data retention with a resistance ratio > 100. The effect of top electrode on the operation mode of hafnium oxide based RRAM were also investigated. Different metal, such as Pt, Ru, PtMn, AlCu, and TiN were used to be the top electrode. To fabricate the RRAM devices, the metal/HfOx/TiN stacked capacitors were prepared by a standard lithograph process or through a shadow mask at room temperature. The operation mode of devices with Pt, Ru, and PtMn as top electrode appeared the characteristics of unipolar, however, the switching behavior of devices with AlCu as top electrode are bipolar. There was no resistive switching in the TiN/HfOx/TiN devices. The interfacial reaction between the top electrode and the HfOx films may be responsible for the different operation mode. The plausible mechanism will be proposed to explain the results.

A1-4 - Atomic Layer Deposition : A Promising Technology (原子層沈積技術之應用與展望)

With the urgent need of device scaling-down and high-density capacity in the IC fabrication, precise control of the process should be undoubtedly essential. Atomic layer deposition (ALD) has been proven to have the ability of forming the uniform and conformal ultra-thin films with varying compositions by the atomic-scaled deposition on the underlying layer, which is advantageous in deep trenches and nano-scaled thin films. This talk will go through the background, reactants, and applications regarding this technology.

Session 2

A2-1 – A Low-Power 60-GHz CMOS Receiver Front-End (60-GHz低功率CMOS接收器前端)

First, the 60-GHz CMOS receiver architectures in the literature will be briefly reviewed. Second, a comparison between the published 60-GHz LNAs and mixers is given based on the S-parameters, NF and linearity performances. Finally, the results of our designed 60-GHz low-power receiver front-end will be discussed.

A2-2 - On the development of 2.4GHz CMOS fully integrated power amplifier (2.4GHz CMOS 功率放大器單晶片設計)

The RF power amplifier is one of the most critical components in a wireless transceiver. Because of the stringent characteristic requirement, the design and integration of CMOS power amplifiers are very challenging. Although the popular OFDM technique has many advantages and has been used in many communication systems, the high PAPR issue degrades the efficiency of the RF power amplifiers significantly. This talk will briefly review the power amplifier efficiency enhancement techniques and discuss the development of 2.4GHz CMOS power amplifier for the communication system adopting OFDM technique.

A2-3 - System-on-chip for high frequency application - RFCMOS technology (高頻單晶片的應用-射頻CMOS技術)

This lecture presents a complete portfolio of RF components by adopting RF-CMOS technology for system-on-chip application. Using optimized CMOS topology and deep n-well, the performances relate to the ft of 60GHz and fmax of 53GHz at 10mA, a ft of 70GHz and fmax of 58GHz at maximum-transconductance bias, and a minimum noise figure of 1.5dB without ground-shielded signal pad. High quality-factor inductors are obtained using thick copper interconnects, the measurement result demonstrates the corresponding quality value of 18 at 1.7nH. The MIM capacitors, as well as accumulation-mode MOS and junction varactors are also optimized for improving quality factor. The variable width transformer is designed to achieve high Q value. For the purpose of eliminating inter-block coupling noise penetrating through substrate, a deep n-well isolation and p-well guard-ring have been adopted to suppress the substrate noise by 25dB and 10dB respectively.

Session 3

A3-1 - Nanometer Scale Metrology Standards and Traceability for Nano Device Manufacture (奈米元件製程之奈米尺寸計量標準)

Nanometer Scale Metrology will discuss measurement standards and traceability for nanotechnology. This development project is supported by Bureau of standard, metrology, and inspection to Establish traceable nanometer-scale measurement standards and metrology methodology, developing atom- or molecule-based metrology standards, as well as acting in concert with National Science and Technology Program for Nanoscience and Nanotechnology to develop nanometer-scale metrology – all of which, aiming to strengthen the long-term development of Taiwan’s industry and economy. They are grating pitch, linewidth, step height, film thickness, particle size, micro-hardness, reduced modulus, Young’s modulus, micro-flowrate, etc.

A3-2 - Systematic Variations in Apparent Topographic Height as Measured by Non-contact and Tapping mode Atomic Force Microscopy (非接觸式與敲觸式原子力顯微術於表面高度測量之系統變異)

The topographic height measurement on a sample consisting of domains of different materials in noncontact atomic force microscopy (NC-AFM) and tapping mode AFM is typically incorrect owing to the variation in electrostatic force between a tip and a sample. The tip-sample electrostatic force is owing to the difference in effective contact potential between a tip and a sample. This study demonstrates that the error in height strongly depends on the bias applied between the tip and the sample, the radius of the tip apex, the work function difference, and the frequency shift. Experimental results are well explained by integrated model calculations and by including the van der Waals and electrostatic forces between the tip and the sample in the analysis. When the simultaneous compensation of contact potentials during imaging is not performed, the errors occurring in the height measurement can be estimated from the tips-ample distance vs the bias curves obtained in situ.

A3-3 - Introduction to tomography and its applications on material science (三維重構技術簡介及其在材料科學上之應用)

Computerized Tomography (CT) is a noteworthy technique introduced relatively new to TEM/STEM and rapidly boosting up 3D nano structure characterization in these days. This technique provides 3D structural analysis in a spatial resolution to sub nanometer after reconstructing a pre-obtained stack of images acquired by systematically changing the tilt angles with an increment of 1 degree in a typical range of ±60° to 70°. As reconstruction process may take time to calculate huge volume of digital data set for the precision position alignment and therefore computation is usually done in an offline computer, followed by real time 3D rendering for visualization of volume, iso-surface, slice and so on. This speech will give an overview of tomography in TEM, and introduce the latest tomography system with its applications.

Session 4

B1-1–Sub-wavelength silicon-wire photonics (次波長矽線波導光學)

Sub-wavelength silicon photonic wires have been demonstrated to realize ultra-compact photonic integrated circuits due to high refractive index of silicon. In this talk, I will summarize our current results on silicon-wire photonics including integration of MEMS-actuated microdisk resonators and applications in nonlinear photonics. Several active functions including dynamic add-drop multiplexing, tunable bandwidth and four-wave mixing will be presented.

B1-2 - Numerical Modeling in Nano-Photonic Devices (奈米光子元件的數值模擬)

In this talk, several numerical techniques for nano-photonics will be addressed. First, the finite-difference time-domain method (FDTD) is introduced. The FDTD is based on Maxwell’s equations with minor approximations. It gives complete information of the time evolution of electromagnetic waves, and therefore it is a very powerful tool for various electromagnetic and optoelectronic devices. However, it is time- and memory consuming, and some treatments in the modeling may be required to alleviate those issues. In addition, parallel processing is often adopted in real three-dimensional structures. Second, frequency domain techniques are introduced including the finite-difference method (FDM), finite-element method (FEM), Fourier series method (FSM), and pseudo-spectral method (PSM). Since the frequency-domain techniques generally require less computation time and memory, they are more efficient in narrow-band applications. Those techniques have their distinct strengths. The FDM is easy to implement, the FEM works well in arbitrary shape, the FSM becomes very efficient in periodic structures, and the PSM has very high accuracy. In addition, they also have some weaknesses and special treatments may improve their performance. Comparisons among the frequency-domain techniques will be addressed. Since the nano-structured devices are generally of high index contrast, a treatment of boundaries on the abrupt interfaces is developed to enhance the performance of the methods. Finally, applications of those to the photonic crystals, plasmonics, and some nano structures will be covered.

B1-3–Computational Nanophotonics: Plasmonic Phenomena in Tailored Metallic Nanostructures (計算奈米光學: 金屬奈米結構中的表面電漿波)

Recent advances in nanofabrication technology have produced exciting opportunities for using ordered structures of metal, semiconductor and other nanoparticles as nanophotonics devices for the control and manipulation of electromagnetic signals for a variety of purposes. Experiments have only just begun to study the nanophotonics properties of various nanoscale architectures, and we are just beginning to learn how to assemble the relevant architectures. There are immense opportunities for combining the theoretical modeling and simulation with experiments to find the “Killer App” of nanophotonics. In our recent work, we use fully parallel 3D Finite-Difference Time-Domain method to study various nanoplasmonic systems. Specifically, we have shown a) the generation of propagating surface plasmon polaritons by a single nanohole in metal thin films, b) the Fano resonant spectrum of enhanced transmission in periodic nano hole arrays, c) the substrate effect which causes the splitting of localized surface plasmon resonant modes of a silver nano cube on glass substrate, d) a full numerical calculation of the near-field scanning optical microscopy (NSOM) imaging by including both the NSOM tip and the metal film, and e) the photochemical imaging by Azo-dye molecules near the metal nanoparticles. By using the AFM topography to map out the near field distribution, we can obtain the sub-nanometer resolution of the near field pattern.

Session 5

B2-1 - New Trend in Development of Silicon Heterojunction Solar Cells (矽基異質接面太陽能電池之發展新趨勢)

The influence of a-Si/c-Si interface properties on the performance of �徯-Si (n)/ a-Si (i)/c-Si (p) solar cells by hot-wire CVD were studied both from experiment results and numerical modeling. After optimizing the emitter and intrinsic layer thicknesses, a set of devices with a 15-nm-thick emitter layer and a 5-nm-thick i-layer was fabricated while the i-layer crystallinity ranged from 0% to 100%. It was found that the short circuit current changes only weakly with the i-layer crystallinity. Numerical simulation and high-resolution TEM highlight that the open circuit voltage (Voc) is dominated by interface conditions such as band offsets and interface defects. From the experimental results, the Si heterojunction solar cell with an amorphous i-layer (5 nm, 20% crystallinity) yielded an active area conversion efficiency over 16%. Details of the correlation between the simulation and experimental data of the �徯-Si (n)/a-Si (i)/c-Si (p) heterojunction are presented. New trends in development of silicon heterojunction solar cells such as selective emitter, back contact structure.. etc. will also be discussed.

B2-2 - Novel device processing with porous anodic aluminum oxide texturing (前瞻元件糙化製程-多孔性陽極氧化鋁技術)

A simple porous texturing technique is used to fabricate both LED and solar cells. Anodic oxidation of Al films leads to a controllable homogenous porous AAO surface layer which enhances the device performances. In solar cell application, commercial single layer TiO2 films shows the reflectance as low as 8.5%, however, as combined with AAO films as double layers ,the reflectance even down to 6.1%. The porous structure makes it a promising candidate as an anti-reflection coating and surface passivation. While in application to LED devices, AAO films also play a significant effect on LED output performance, it promote even 40% than that without AAO films. The simplicity of this process makes it a very promising technology into industrial production.

B2-3 - 高效率矽薄膜太陽電池技術

太陽電池的開發已被美國、日本及歐盟等國列為重要的發展課題，但矽原料短缺的問題導致矽晶太陽電池年產量減少。矽薄膜太陽電池由於矽原料使用較少，並且轉換效率較不受環境溫度、照度等因素影響，因而引起重視。另外，矽薄膜太陽電池在市場應用面上，可整合於玻璃帷幕當作建材使用，有其利基點。綜合以上優勢，矽薄膜太陽電池逐漸吸引眾人目光，國內外矽晶太陽電池大廠及設備廠商莫不紛紛投入該領域的研究與生產。但不管是元件製程或大面積模組量產其實仍有許多需努力突破的地方。

Short Course A

A-1 - NanoImprint Lithography: Technology, Materials, Applications

NanoImprint Lithogaphy has developed to a mature technology that now has entered industrial production. Different NIL technologies are introduced and basics like stamp and imprint materials are discussed. Layout strategies for stamp design play an important role for the imprint result and general rules are presented to the audience. Finally an overview on different application areas for NIL will be given showing examples and results.

A-2 – Applications of TEM in nano-materials analysis

A-3 - Nano prototyping using FIB

The potential of focused ion beam equipment for prototyping of micromechanical structures has been recognized. Until recently, this potential has mostly been exploited using case-specific deposition and milling geometries and design/fabrication strategies that were tailored to individual designs. This way of working limits the design complexity because of the limited amount of milling/deposition operations that can be done in a practical and timely fashion. This lecture will focus on (new) techniques which can be used to quickly realize complex designs using a Dual Beam system. Short

Short Course B

B-1 – Biochip development for biomedical applications: drug screening and discovery

The scale production of chip/semiconductor used for electronic devices (computer, etc) is very outstanding in Taiwan. However, the techniques by combining chip-based and surface chemistry (such as self-assembled monolayers) as an interface used for the biomedical applications is only on the early infant stage in Taiwan. Connection between these technologies with the strong background of producing chip capability is essential. In this short-course, a successful example by using chip as a base to apply to biomedical uses: drug screening and discovery will be introduced. A method called “After Flowing Through Immobilized Receptor (AFTIR)” is used. Using AFTIR, we have successfully identified an effective compound, cynarin, in Echinacea purpurea (a western herb) by its selective binding to chip immobilized CD28, a receptor of T-cell, which is instrumental to immune functioning. The results of surface plasma resonance show that binding between immobilized CD28 and cynarin is stronger than the binding between CD28 and CD80, a co-stimulated receptor of antigen presenting cells. AFTIR offers promise as an efficient chip-based drug screening method and for the drug discovery.

B-2 - Development of self-assembled monolayers (nano scale films) technique on chip

Self-assembly provides a simple route to organise suitable organic molecules on noble metal and selected nanocluster surfaces by using monolayers of long chain organic molecules with various functionalities like –SH, –COOH, –NH2, silanes etc. These surfaces can be effectively used to build-up interesting nano level architectures. Flexibility with respect to the terminal functionalities of the organic molecules allows the control of the hydrophobicity or hydrophilicity of metal surface, while the selection of length scale can be used to tune the distant-dependent electron transfer behaviour. Self-assembled monolayer (SAM) coatings have been a common technique employed in MEMS, optics, and life science applications for the modification of surfaces. These nano-scale film capabilities will have significant importance in improving the functionality and reliability of many micro- and nano-scale devices. For example, the two components that make up a biosensor are the biological recognition layer, which selectively binds the analyte, and the transducer, which translates this recognition event into an electrical signal. The interfacial design of biochip/biosensors is of the utmost importance since it determines the specificity, stability, reproducibility, and durability of the biosensor as a whole. Interface requirements are strongly dependent on the final biochip/biosensor application.

B-3 - A Discrete Mathematical Modeling of Self-assembly Monolayer

Self-assembly monolayers(SAMs) are surfaces consisting of a single layer of molecules on a substrate. It is well-known that we can prepare SAMs by adding a solution of the desired molecule onto the substrate surface and washing off the excess. But, certain types of molecules, carried by a solution is not possible, instead a chemical vapor deposition is utilized to accomplish the job. This technique has its advantage and disadvantage. The main set back is due to its poor control over the thickness of the molecular layer. Therefore, knowing when and how the monolayer has been obtained is the main task of this study. In this talk, we shall propose a discrete mathematical model based on the distribution of molecules onto a lattice with different probabilities to derive a better way to obtain a self-assembly monolayer. Here, a better way means a better control of diffusion and also the density of molecules.