Smit Center Shanghai

Invited Talk 1: Buckle-driven Delamination of Thin Film and The Influence of The Casimir or van der Waals Force Interaction

Speaker: Yu Shouwen , Li Qunyang, Department of Engineering Mechanics, Tsinghua University, Beijing 100084, China, Yusw@mail.tsinghua.edu.cn

Abstract

Indentation test is becoming increasingly used to quantitatively assess the thin film interfacial adhesion for its simplicity and ability to mechanically probe the smallest of solids. The conventional technique is based on the analysis of a combination of Linear Elastic Fracture Mechanics ( LEFM ) and simplified post-buckling theory. In this paper a full post-buckling response of thin film is investigated by FEM calculation; the contributions of double-buckling to the indentation test is discussed. The results show that double-buckling needs more energy than single-buckling case thus lead to a greater value of strain energy release rate。Finally, the influences of the Casimir or van der Waals interaction on the post-buckling behavior between the thin film and substrate are considered.

Invited Talk 2: Conductivity Improvement of Isotropically Conductive Adhesives

Speaker: C. P. Wong, School of Materials Science and Engineering and Packaging Research Center, Georgia Institute of Technology, Atlanta, GA 30332. E-mail: cp.wong@mse.gatech.edu Phone: (404) 894 8391 Fax: (404) 894 9140

Abstract

To further increase the conductivity of isotropically conductive adhesives, short-chain dicarboxylic acids, such as malonic acid (acid M), adipic acid (acid A) and terephthalic acid (acid T), were introduced in a typical ICA formulation. By partially removing or replacing the surfactant stearic acid in silver(Ag) flakes, such dicarboxylic acids have potential to increase the conductivity of ECAs. With the addition of malonic acid and adipic acid, which only have short single-bond chain hydrocarbon between the dicarboxylic groups, the conductivity of the typical conductive adhesives were improved significantly. Terephthalic acid, however, deteriorates the conductivity due to the rigid aromatic structure in the molecule. Dynamic mechanical analysis and thermomechanical study indicated the improved electrical properties with malonic and adipic acids were achieved without negatively affecting the mechanical and physical properties of ECAs.

Biography Of Speaker:

Dr. C.P. Wong is a Regents’ Professor(highest ranking professor) of Materials Science and Engineering and a Research Director of the NSF-funded Packaging Research Center at the Georgia Institute of Technology. His research interests lie in the area of polymeric materials (organic and inorganic), in particularly, low-cost, high-performance materials and manufacturing processes. Prior in joining Georgia Tech in 1996, he was with AT&T Bell Laboratories for 19 years and was elected an AT&T Bell Labs Fellow in 1992. He holds over 40 U.S. patents, numerous international patents, and has published over 400 technical papers and 350 presentations in the packaging related areas. Dr. Wong received the B.S. degree in chemistry from Purdue University, the Ph.D. degree in chemistry from Penn State University, and was a Postdoctoral Fellow with Nobel Laureate Prof. Henry Taube at Stanford University. He received many Awards from the IEEE, IMAPS, AT&T Bell Labs, and the Georgia Tech(GT). Among those the GT 1999 Outstanding Research Program Award, the 1999 NSF-ERC Packaging Research Center Faculty of the Year Award, the IEEE EBA Award in Continue Education in 2001, the Exceptional Technical Contribution Award in 2002 and the Henry Toops Award in 2003. He serves on the Editorial Boards of the IEEE Trans. on Components, Packaging Technology, the Chip Scale Review and he is the editor-in-chief of the John-Wiley Encyclopedia on Smart Materials. He is a fellow of IEEE, AIC and Bell Laboratories and is a member of the National Academy of Engineering of the USA.

Invited Talk 3: Design and Implementation of System-on-Package Modules for Radio and Mixed-Signal Applications

Speakers: Li-Rong Zheng*, Xingzhong Duo, Meigen Shen, Tommi Torrika, Wim Michielsen, Hannu Tenhunen, Royal Institute of Technology (KTH), SE-164 40 Kista-Stockholm, Sweden & Liu Chen and Gang Zou and Johan Liu, SMIT Center, Chalmers University of Technology and IVF, Argongatan 30, Gothenburg, Sweden

Outline of Speech:

Wireless communication has changed our daily life in many aspects. It is expected that wireless industry will have further growth over the next several years, in part by finding new applications such as in logistics, intelligent home networks, medical information systems, and wireless ad hoc networking, in addition to the conventional telecommunication applications. System-on-package concept is considered as a promising solution for future integrated wireless communication modules, which would need more functionality, higher data rate, lower cost and more robustness.

In this paper, we analyze challenges and opportunities for system-on-package module for future radio and mixed-signal applications with a particular focus on these emerging wireless applications such as multi-band and multi-standard radio for 4G and beyond 3G wireless, ultra wide-band radio for gigabit wireless. We will show how SoP technology can address the integration platform for these applications and how this can be done in a better way than system-on-chip integration. Some design examples will be presented. The first one is an RF receiver front-end for 5GHz wireless LAN application. The front-end is design with GaAs monolithic microwave integrated circuits and liquid-crystal polymers-based SoP technology. Due to high quality of passive components in SoP, superior RF performance is found in this module. In the second example, we address several critical design issues for on-chip versus off-chip passive components for SoP integration. This is demonstrated through several RF building blocks for a multi-band and multi-standard radio for 4G and beyond 3G wireless such as multi-band voltage controlled oscillator, concurrent multi-band low noise amplifier. Chip-package co-design for smart parasitic absorption is demonstrated through an RF module for an ultra-wide band radio in gigabit wireless. Finally, we discuss some system level integration issues and we will show how a system can be smartly partitioned for SoP so that it is an optimal total solution for wireless integration and implementation.

In addition to the above-mentioned research results, we will also present several new concepts for future wireless SoP using new components such as RF-MEMS and some smart components from new-invented materials. We will show how these new components and materials can result in simple circuit architecture and RF integration.

Biography of Speaker:

Dr. Li-Rong Zheng holds a Doctor of Technology degree in electronic system design from the Royal Institute of Technology (KTH), Stockholm, Sweden, in 2001. Since then, he has been with KTH as a teacher and a researcher. He is currently an associate professor and research fellow in the Department of Microelectronics and Information Technology at the Royal Institute of Technology, where he is leading a research group in mixed-signal integration and system-on-package. His current research activities include innovative packaging solutions such as SoP and related design techniques for wireless and broadband communications, deep submicron VLSI design for mixed-signal applications, and interconnect centric system-on-chip design. He also teaches several undergraduate and graduate courses at KTH in the above areas, and also gives many short courses in international workshops as well as to local industry.

Dr. Zheng is a technical program committee member of European Solid-State Device Research Conference (ESSDERC), program committee member of EPROPER- the Swedish national strategic research program on electronic package and production, and a board member of IEEE CMPT Scandinavia Chapter. He has published over 100 peer-reviewed articles in international journals and conference proceedings. Recently, he is frequently giving invited talks and tutorial lectures on interconnect-centric SoC design and mixed-signal system-on-package design in international conferences and industry

Invited Talk 4: Development of a Lead-free, Low-temperature Sintering Die-Attach Technique for High-performance and High-temperature Packaging

Speaker: Dr. Guo-Quan Lu, Professor ,Director of Microsystems Integration and Packaging Lab, Departments of MSE and ECE, Virginia Tech, 213 Holden Hall, Blacksburg, VA 24061, USA

Outline of Speech:

For semiconductor devices to function in products, they need packaging to provide interconnection and protection. Die-attach materials, which join the devices to rest of the system, play a vital role in ensuring the system performance and reliability. Today, lead-tin and lead-free solder alloys and conductive epoxies are widely used for attaching the devices. Because they can be easily processed at a low temperature below 300oC. As the electronics industry continues to integrate more functions in smaller packages, the electrical, thermal, and mechanical properties of the existing die-attach materials cannot meet the more demanding requirements for performance and reliability. In this talk, I present a die-attach technique based on sintering silver pastes to interconnect devices.Two strategies have been taken to lower the sintering temperature down to 300oC: one involves using quasi-hydrostatic pressure to increase the sintering driving force; and the other relies on nanoscale silver particles to densify the material without pressure. Experimental measurements on the sintered joints show significantly improved electrical, thermal, and mechanical properties over the soldered joints. This silver-sintering die-attach technique opens the possibility for interconnecting wide band gap semiconductor devices (SiC or GaN) that are operable over 350oC where none of the existing solder alloys can be used.

Biography of Speaker:

Dr. Guo-Quan (GQ) Lu is Professor in MSE and ECE at Virginia Tech. He received his Ph.D. in Applied Physics/Materials Science from Harvard University in 1990. Then, he worked at Alcoa Technical Center for Alcoa Electronic Packaging Inc. before coming to Virginia Tech in 1992. His research activities and interests are in the general area of materials and process development for applications in microelectronics, power electronics, optoelectronics, sensors, and nanotechnology. Dr. Lu is Leader of the Integratable Materials thrust in the Center for Power Electronics Systems, an NSF Engineering Research Center based at Virginia Tech. He has been responsible for developing several three-dimensional packaging technologies for integrated powerelectronics modules. Dr. Lu holds three U.S. patents and has published over 100 papers in journals and conference proceedings. He was the 1995 winner of Virginia Tech Sporn Award for excellence in teaching of engineering subjects and was the recipient of a National Science Foundation CAREER award in 1995.

1 2 3