12 Jan 2012   |   9:00 am to 1:30 pm,   Theatrette, Level 1, TÜV SÜD PSB Building, 1 Science Park Drive, Singapore 118221

Seminar on Nano-scale Measurements ̶ Development, Applications, Trends and Challenges


Nano-scale measurement deals with physical features of 100 nm or smaller.  Relentless pace in miniaturization in high-technology industrial sectors, such as in microelectronics and data storage, and the increasing demand for nano-scale products, underscore the urgent need for accurate and repeatable nano-scale measurements.  Nano-scale measurements find potential applications in many industry sectors, such as automobile, aeronautics, health and medical systems, and energy.  A nano-scale vision in the medical field provides many benefits.  For example, nano-scale robots can be injected into a body to detect cancerous cells with nano-sensors and remove them with nano-cutters.  For such futuristic high-technology inventions, the capability to do precise measurements in the nano-scale is a must, and new methods for measuring and characterising different nano-scale parameters, such as nano-scale aspect ratios, channels and diameters, have to be developed.  The seminar looks into some of the technical challenges and issues, and serves as a platform for sharing and exchange of ideas.

National Metrology Centre (NMC) is organising the seminar jointly with Institute of Materials Research and Engineering (IMRE).  Topics covered include current state of dimensional nanometrology, nano-scale material characterization and instrumentation, metrology standards, industry applications and R&D activities. 


8:30 am


9:00 am

Welcome Address
Ms Tan Siew Leng, Principal Metrologist and Head of Optical Metrology, National Metrology Centre

9:10 am

Quantitative Measurement of Physical Properties at Nano-scale
Dr  Sun Wanxin, Applications Scientist, Manager, Bruker AXS Pte Ltd


Physical properties of materials at nanometre scale are important for both scientific researches and a variety of applications, ranging from nanomaterials synthesis, nano-device fabrication and green energy, to life science and biomedical applications. For example, both electrical and mechanical properties of lithium battery materials play critical roles in battery performance and safety. In organic solar cells, the structure and electric connectivity of donor and acceptor materials determine the final efficiency.

Invented more two decades ago, the scanning probe microscope (SPM) has been well accepted as a platform for nanomaterial characterization due to its capability of providing rich information at nanometre spatial resolution.  SPM does not require vacuum to achieve such high resolution, and can measure electrical and mechanical properties. However, some issues include the local interaction effects between the probe and sample, lack of predictability and control of local contact in conventional AFM, and challenging samples.

In this talk, we will discuss new developments in SPM technologies, enabling accurate force control at pN level and eliminating lateral force, thus enabling one-button operation and eliminating human errors. In addition to topography, a collection of mechanical properties and electric properties are obtained simultaneously. As an example, experiments on lithium battery applications and some vertical aligned carbon nanotubes illustrate the capabilities.

9:35 am

Scanning Probe Microscopy: from Surface to Interface Characterization at the Nanoscale
Dr Cedric Troadec, Scientist, Institute of Materials Research and Engineering (IMRE)


Scanning Probe Microscopy (SPM) has developed rapidly since its invention to help visualize and understand material surfaces and adsorbates at the atomic scale. Conducting materials are more suitable for Scanning Tunnelling Microscopy (STM), whereas insulating materials are more suitable for Atomic Force Microscopy (AFM) for imaging purposes. The atom ordering at the interface of diverse material heterostructures can also be easily assessed by Transmission Electron Microscope (TEM). In this talk, the use of SPM in IMRE for nanotechnology for fabrication and characterization will be presented. The different scales, from atomic to molecular to nano-scale, and different equipment and techniques available at IMRE will be covered.
Apart from high spatial resolution, a high level of characterisation can be achieved in the energy scale, from object/surface interaction (STM, AFM) to energy band level alignment using complimentary techniques like Ballistic Electron Emission Microscopy.

10:00 am

Surface and Interface Characterization of GaN-based Heterostructure for Tansistor Applications
Prof Radha Krishnan, Associate Professor, Division of Microelectronics, School of Electrical and Electronic Engineering, Nanyang Technological University


The heteroepitaxial growth of III-nitrides on silicon is attractive because of its low cost and larger size compared to conventional substrates such as sapphire and SiC.   Moreover, GaN-on-Si platform is interesting for potential integration of GaN-based devices with established Silicon electronics.  However, the large lattice constant and thermal expansion coefficient mismatches are some of the challenges in realizing nitride heterostructures on Si.  Metal organic chemical vapour deposition (MOCVD) has been used to demonstrate AlGaN/GaN high electron mobility transistors (HEMTs) on Si(111).   However, molecular beam epitaxy (MBE) growth presents several advantages over MOCVD including lower growth temperatures and hence lesser stress in the epilayer, precise control over the layer thickness, possibility of in-situ characterization, etc.
In this study, surface and interface characterization techniques by AFM, TEM and SIMS have been used to optimize the MBE growth of GaN-based heterostructures on 100 mm diameter silicon wafers for high electron mobility transistor applications. Some of the layer structures implemented to mitigate the effect of large stress, and hence control the cracking of wafers, will be discussed.  The optimized structures with enhanced structural and electrical properties will be correlated to the layer structure design and growth parameters.  Results obtained from the fabricated HEMT devices will also be presented.

10:25 am

Tea Break & Exhibition

11:00 am

Nanometrology Development and Activities at the National Metrology Centre
Dr Wang Shihua, Senior Metrologist, Optical Metrology, National  Metrology Centre (NMC)


This presentation introduces the nanometrology development and activities in the Length and Dimension Lab at the National Metrology Centre.  The talk will discuss nano-scale measurement trends and challenges, and specifically covers the development of a large range metrological atomic force microscope (LRM-AFM) and its application for carrying out calibration and measurement (C&M) of nano-scale step height and lateral pitch standards.  These working standards are used for calibrating and improving the accuracy of other higher magnification & precision optical microscope and SPMs including SEM, TEM and AFM.  Applications will also be presented to demonstrate LRM-AFM calibration and measurement capabilities of large groove steps and nano-scale displacement in a PZT nano-stage.  In addition, comparison results confirming the performance of the LRM-AFM will be shared.

11:25 am

Failure Analysis Challenges for Nano-scale CMOS Devices in Semiconductor Industry
Mr Vinod Narang, Team Lead, Member of Technical Staff, Advanced Micro Devices, Singapore


Semiconductor Industry continues to innovate over the last 40 years with Moore’s law pushing CMOS devices into nano-scale realm.  Failure Analysis plays a significant role in the innovation cycle especially during Product Development, 1st Silicon Bring-up and Wafer process yield improvement to identify root cause of failures.  A typical failure analysis flow includes non-destructive testing, fault isolation to isolate the defective region and physical failure analysis to identify the physical defect causing device failure.
This presentation provides an overview of various failure analysis tools.  The aim of the presentation is to provide sufficient depth to each topic including relevant case studies to emphasize the key points related to each methodology.  The presentation will also cover relevant future directions and roadmap which are critical to tackle ever advancing process technology and product complexity. 

11:50 am

Nanomechanical Characterization of Single Nanofibers
Prof  Lim Chwee Teck, Professor, Departments of  Bioengineering and Mechanical Engineering, National University of Singapore


Electrospun polymer nanofibers are being increasingly explored for biomedical applications such as regenerative medicine and controlled drug delivery, due to their high surface-to-volume ratio and biocompatibility.  However, as the nanofibers are constantly exposed to physical stresses while in use, it is important that their structural integrity is not compromised and that they do not fail. 
Nanomechanical testing has not been widely performed due to the nanofibers’ small size.   Yet, such tests are important as the structural makeup and mechanical properties have been found to vary significantly for nanofibers with diameters ranging from tens to hundreds of nanometres.  These tests can help us to better understand the structure-property relationship at the nanoscale.  Here, we present three-point bend test, tensile test as well as nanoindentation tests of single polymer nanofibers.  Our results showed that the mechanical properties of the nanofibers are diameter dependent.  These results will enable us to better relate the nanomechanical properties to the nanostructural rearrangement and makeup of the nanofibers.

12:15 pm

Nano Defect Detection in Wafer Manufacturing
Dr. Sunny Cheng, Optical Engineering Manager, KLA-Tencor (Singapore) Pte Ltd


This presentation reviews nanoscale defects inspection method and instruments by using laser scattering in wafer manufacturing.  It will focus on detection mechanisms of surface scan system, instruments architecture, minimum detectable size for the particle, and inspection throughput, etc.  The effect of new lasers on nano defect detection system development will be discussed.  The challenges for short wavelength laser and optical components will also be briefly discussed.

12:40 pm

Lunch & Exhibition

1:30 pm

End of Event


Dr  Sun Wanxin, Applications Scientist, Manager, Bruker AXS Pte Ltd

Dr Sun holds a PhD degree in Physics, as well as M.Eng. and B.Eng. degrees in precision metrology and instrumentation.  During his research career as PhD candidate and Post-Doctoral Fellow, he worked on near-field optics and its applications in semiconductor fabrication in National University of Singapore.  After that, he worked in Institute of Bioengineering and Nanotechnology, in the areas of bioimaging, bio analysis and tissue engineering. He has developed several microscopic techniques, published more than 40 papers in international journals, and has been inventor of several US patents. Besides research, he is also active in relevant societies and chairs sessions in international conferences. Dr Sun joined Veeco in 2006 (Veeco metrology group has become Bruker Nano Surfaces Division), where he is responsible for application development and technical support of metrology instruments in Asia Pacific region.

Dr Cedric Troadec, Scientist, Institute of Materials Research and Engineering, A*STAR

Dr Cedric Troadec completed his PhD in Physics at the Royal Holloway College, University of London in 2001. His thesis was on hybrid superconductor/ ferromagnetic metallic nanostructures: fabrication and study of the proximity effect. After working for ThermoVG Semicon designing gas cells for molecular beam epitaxy, he joined the Institute of Materials Research and Engineering (IMRE) in 2003, where he presently works as a Scientist. He is leading the development of ballistic electron emission microscopy for the characterization of metal/organic interfaces. He also participates in the European project AtMol to fabricate the first molecular device bottom-up.

Prof  Radha Krishnan, Associate Professor, Division of Microelectronics, School of Electrical and Electronic Engineering, Nanyang Technological University

Dr. Radhakrishnan received his MSc (Applied Physics) and MTech (Materials Science) degrees from University of Madras and Indian Institute of Technology, Kanpur in India, respectively, and PhD degree in Physics from National University of Singapore in 1989.  Since 1991, he has been with Nanyang Technological University, where he is now an Associate Professor in the School of Electrical and Electronic Engineering.  His expertise is in molecular beam epitaxial growth and characterization of III-V compound semiconductors, low-dimensional and metamorphic compound semiconductor structures, fabrication of GaAs and InP based high electron mobility transistors and heterojunction bipolar transistors, and monolithic integration of devices for high-speed circuits.  His current research interests include growth and characterization of GaN-based heterostructures for high power/high frequency applications.  He was awarded Defence Technology Prize in 2008 for outstanding technological contributions to Monolithic Microwave Integrated Circuit Research & Development Team (R & D Category) by MINDEF Singapore. He is a member of IEEE and MRS.

Dr Wang Shihua, Senior Metrologist, Optical Metrology, National Metrology Centre, A*STAR

Dr Wang Shihua is a Senior Metrologist in Optical Metrology, and is currently involved in the length and dimensional calibration & measurement in both micro-scale and nano-scale order and particularly nanometrology activities using a large scanning range metrological atomic force microscope (LRM-AFM).  Dr Wang received his BEng, MEng and PhD degrees from Sichuan University, Chengdu, China, in 1987, 1990 and 1996 respectively. Prior to joining NMC in 2005, Dr. Wang worked as a Research Fellow in the Department of Mechanical and Production Engineering, National University of Singapore and a Lecturer and Associate Professor in Sichuan University, China. He is the author or co-author of over 70 published scientific papers. His R&D interests include surface metrology using laser, white-light interferometry and laser confocal microscopy, length and dimensional measurements, light scattering surface roughness measurement, MicroElectroMechanical Systems (MEMS) testing and optics-mechanical design.

Mr Vinod Narang, Team Lead, Member of Technical Staff, Advanced Micro Devices, Singapore
Mr Narang has been working as Member of Technical Staff with Device Analysis lab AMD, Singapore since 2005.  He is team leader of Silicon level failure analysis group and working on Reliability Qualification, Customer Rejects and Silicon Bring up of advanced Microprocessor products based on 32nm & 28nm technology nodes.  Prior to joining AMD, he worked with TECH Semiconductor, a Micron Technology JV DRAM wafer fab on product yield failure analysis for various process technologies from 180nm to 110nm. He has also worked in India with Thapar R & D Group as Materials Research Engineer. His areas of interest include advanced failure analysis tools and techniques development, plasma and wet etch based recipe development and physical failure analysis. Mr Narang obtained Master’s degree in Advanced Materials with focus on Microelectronics from Singapore MIT Alliance in 2000, and is expected to graduate from Flex Time MBA program from SMU in 2011.

Prof  Lim Chwee Teck, Professor, Departments of  Bioengineering and Mechanical Engineering, National University of Singapore

Dr Lim Chwee Teck is a Professor at the Departments of Bioengineering and Mechanical Engineering at the National University of Singapore. He heads the Nano Biomechanics Lab which conducts research in cell and molecular biomechanics of human diseases, development of microfluidic devices for the detection and diagnosis of human diseases as well as nanomechanical testing of nanobiomaterials. Prof Lim has recently been elected as a Council Member of the World Council for Biomechanics. Prof Lim has authored or co-authored more than 180 journal papers (including 30 invited/review articles and 11 ISI highly cited papers), 17 book chapters and delivered more than 175 invited talks. He is currently on the editorial boards of 11 international journals.He has won several research awards including the President’s Technology Award and IES Prestigious Engineering Achievement Award. His research was cited by the MIT Technology Review magazine as one of the top ten emerging technologies of 2006 that will "have a significant impact on business, medicine or culture".

Dr Sunny Cheng Xiangyin, Optical Engineering Manager, KLA-Tencor (Singapore) Pte Ltd

Dr Cheng received his BEng, MEng and PhD, all in Optical Engineering from Tsinghua University, Beijing, China.  Currently, Dr Cheng is a Manufacturing Engineering Manager for optics in KLA-Tencor (Singapore).  From 2003 to 2006, he was a Chief R&D engineer & Cluster Leader of Optical group in Phillips Electronics, Singapore to develop re-writeable optical pickup unit for CD/DVD/BD.  From 1999 to 2002, he was a R&D manager in Blue Sky to develop optical telecommunication and optical storage products, including 980 nm pump laser module packaging, optical switch, EDFA amplifier and CD RW Optical Pick Up unit. He has extensive R&D experience in optical industrial sectors.