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HOT!	2023	恭賀！古沅翰、林佑欣同學榮獲2023台積電博士獎學金
HOT!	2022	恭賀！張復翎同學榮獲2022台積電博士獎學金
HOT!	2021	恭賀！高振宏教授榮獲科技部傑出特約研究員 (Merit MOST Research Fellow)
HOT!		恭賀！高振宏教授榮獲ECTC Volunteer Award, IEEE Electronics Packaging Society
HOT!		恭賀！施柏紹、黃薇禎同學榮獲2021台積電博士獎學金
HOT!	2020	恭賀！高振宏教授榮獲 2020 Functional Materials Division Distinguished Scientist Award, TMS (美國礦物、金屬、材料學會)
HOT!		恭賀！高振宏教授榮獲 Top 1% in Applied Physics according to standardized citation ranking by Ioannidis et al of Stanford University
HOT!		恭賀！洪漢堂同學榮獲Best Student Paper Award, 2020 IMPACT-EMAP
HOT!		恭賀！黃正豪同學榮獲2020台積電博士獎學金
HOT!	2019	恭賀！高振宏教授榮獲 Best Interactive Presentation Paper Award, 2019 IEEE Electronic Components and Technology Conference
HOT!		恭賀！洪漢堂同學榮獲 Best Interactive Presentation Paper Award, 2019 IEEE Electronic Components and Technology Conference
HOT!		恭賀！楊弘偉同學榮獲 Intel Best Student Paper Award, 2019 IEEE Electronic Components and Technology Conference
HOT!		恭賀！楊弘偉同學榮獲 2019 IEEE ECTC Student Travel Award
HOT!		恭賀！楊弘偉同學榮獲 2019 台灣半導體產業協會 (TSIA) 博士研究生半導體獎
HOT!		恭賀！李珮慈同學榮獲 2019 National Synchrotron Radiation Research Center 25th Users’ Meeting & Workshops Poster Award
HOT!		恭賀！高振宏教授榮任 IEEE Components, Packaging and Manufacturing Technology Society 理事 (Board of Governors), 任期2016-2018年與2019-2021年。該學會是 IEEE 旗下38個學會之一, 也是世界規模最大之電子零組件與封裝製造之相關學會。
	2017	恭賀！楊淳安同學榮獲 2017 IEEE Electronic Components and Technology Conference Texas Instruments Outstanding Student Interactive Presentation Award
		恭賀！高振宏教授榮任國立台灣大學特聘教授
	2016	恭賀！楊竣翔、楊弘偉同學榮獲 2016 IEEE Japan Chapter Young Award
		恭賀！楊竣翔同學榮獲 2016 PCB學生優秀論文獎
		恭賀！余人睿同學榮獲 2016 IEEE ECTC Student Travel Award
	2015	恭賀！余人睿同學榮獲 2015 Japan Insitute of Elecronics Packaging Poster Award
		恭賀！李澄傑同學榮獲 2015 TMS Best Paper Award
		恭賀！高振宏教授榮任亞太材料科學院院士, Academician, Asia-Pacific Academic of Materials, 2015
	2014	恭賀！楊挺立同學榮獲 IMPACT-EMAP 2014年 "Student Paper Award"
		恭賀！鍾丞凱同學於第13屆世界電子電路大會 (ECWC13)中獲得優秀論文獎(Best Paper Award)殊榮
		恭賀！楊挺立同學獲得2014年台灣半導體產業協會第一屆博士研究生半導體獎
	2013	恭賀！高振宏教授榮任「國科會材料工程學門」召集人
		恭賀！高振宏教授參加國科會工程技術發展處102年度技術及知識應用型產學合作計畫榮獲"產學成果優良獎"
		恭賀！高振宏教授之學生鍾丞凱同學榮獲"奇美實業優秀人才獎學金"
		恭賀！高振宏教授榮獲美國TMS學會2014年"BRIMACOMBE MEDALIST AWARD"
		恭賀！楊挺立同學獲美國IBM公司於 2013/10/30之IBM Intern Spotlight Program中報導
		恭賀！高振宏教授在 Journal of The Minerals, Metals & Materials Society, Vol. 65, No.9, SEPTEMBER, 2013 期刊中發表評論
		恭賀！鍾丞凱同學榮獲2013 IMPACT論文金獎
		恭賀！楊挺立同學獲得2013年中國材料科學學學年會學生海報論文獎佳作
		恭賀！高振宏教授獲邀擔任High Impact Research Icon, University of Malaya, Kuala Lumpur, 2013-2015.
		恭賀！高振宏教授學術文章獲選為國際知名期刊Journal of Applied Physics之封面文章
	2012	恭賀！高振宏主任指導之博士生楊挺立同學於2012年先進功能材料全國博士生學術論壇暨海峽兩岸博士生論壇獲獎
		恭賀！實驗室多位同學在2012 MRS-T材料年會獲得獎項優勝：陳郁仁、郭楣詩 [3D IC微尺度下微小銲點之金脆效應] 優勝：楊挺立 [Sn Grain Orientation Effect on the Formation of Highly Serrated Cathode Interface in Solder Joints under Electromigration] 佳作：李澄傑、余人睿、朱子軒 [Volume shrinkage induced by interfacial reaction in micro Ni/Sn/Ni structure]
		恭賀！楊挺立同學獲得2012 PCB學院優秀論文獎優等，於2012年10月24日TPCA Show 開幕式頒發獎項
		恭賀！高振宏教授榮任 International Materials Reviews (Impact Factor=6.962) Editional Board
		恭賀！高振宏教授榮任美國金屬學會會士
		依照ISI Essential Science Indicators 2012.5.1版統計,MICROELECTRON REL, 49 (3): 248-252 MAR 2009已被ISI列為 "HighlyCited Papers"，亦即該文被引用次數排名其領域前1%。本團隊已第五次獲取此榮譽
	2011	恭賀！高振宏教授論文為TMS引用次數最高十篇之一
		恭賀！郭楣詩、莊鑫毅同學榮獲2011 PCB學院優等獎
		恭賀！余人睿同學榮獲12th世界電子電路大會最佳論文獎
		恭賀！楊挺立同學榮獲AMD Technical Forum and Exhibition 2011最佳海報論文獎
		恭賀！高振宏教授擔任The Minerals, Metals & Materials Society 的 William Hume-Rothery Award, Champion H. Mathewson Award,Institute of Metals Lecture/Robert Frankly Mehl Award, and Acta Materialia Gold Medal Award Subcommittee與John Bardeen Award Committee 委員會委員

Projects

Research Focus

Flip Chip Package / Lead Free Solder / 3D IC / Elecromigration

Flip Chip Package

Smaller, thinner and more powerful components have been regarded as the future trends of the electronic appliances, such as laptop PCs, hand phones, Palms etc. These trends set more stringent tasks for electronic packaging industry in recently years. In order to fulfill these requirements, flip chip technology was selected as one of the substitutes for the conventional packaging technologies. In flip chip technology, the Si chip is flipped over and connected to substrate via either area array or peripheral solder bumps, as the figure depicted below. Our research focus on interfacial reaction between the solder bump and the under-bump metallurgy (UBM).

Lead Free Solder

Due to environmental concerns, the need for lead-free solutions in electronic components and systems is receiving increasing attention within the semiconductor and electronics industries. Several types of lead-free solder, such as Sn-Ag, Sn-Ag-Cu, and Sn-Bi, are investigated.

The electronic industry has been using Pb-bearing solders for interconnection applications for over 50years. These Pb-bearing solders include alloys such as 63Sn-37Pb (wt %, Sn37Pb), frequently used for soldering printed circuit boards (PCBs), and Sn95Pb, frequently used for chip-to-package connection. There are several pending national and international legislation proposals banning the use of Pb in these solders. The Sn3.9Ag0.6Cu solder is one of the most promising lead-free candidates to replace the Sn37Pb solder. The allowance for concentration variation for each element in this solder is customarily taken to be about 0.2 wt %.

3D IC

In electronics, a three-dimensional integrated circuit (3D IC, 3D-IC, or 3-D IC) is a chip in which two or more layers of active electronic components are integrated both vertically and horizontally into a single circuit. The semiconductor industry is hotly pursuing this promising technology in many different forms, but it is not yet widely used; consequently, the definition is still somewhat fluid.

3D packaging saves space by stacking separate chips in a single package. This packaging, known as System in Package (SiP) or Chip Stack MCM, does not integrate the chips into a single circuit. The chips in the package communicate with off-chip signaling, much as if they were mounted in separate packages on a normal circuit board. In contrast, a 3D IC is a single chip. All components on the layers communicate with on-chip signaling, whether vertically or horizontally. Essentially, a 3D IC bears the same relation to a 3D package that an SoC bears to a circuit board.

Elecromigration

For high performance electronic devices, the current trend is a wider application of flip chip technology to microprocessors and wireless handled electronic consumer products. Flip chip interconnects are used in the electrics industry primarily because of their high I/O density capacity, small profiles, and good electrical performance. It is expected this interconnecting technology will become even more important in the near future.

In flip chip packages, the number of I/O contact pads on a chip surface increases and the diameter of solder bumps decreases, the current density in passing through the contact area of a solder bump increase very rapidly. For example, flip chip interconnect with a 125 μm diameter and 250 μm pitch can form a full array of 2000 interconnects on a chip of 1×1 cm². If the diameter and pitch are reduced to 50μm and 100 μm, respectively, 10000 interconnects are possible on the chip. Current circuit design rules require that each interconnect carry a current of up to 0.2 amp with an interconnect to 0.4 amp in near future. The current density will reach 104 A/cm² for the bump with 50 μm diameter.

Electromigration is one of the failure mechanism needed to concern at high current density. The popular composition for flip chip solder bumps is eutectic Sn-Pb solders, although it is challenged by Pb-free solders such as Sn-Ag or Sn-Ag-Cu solders. The eutectic Sn-Pb solder has a low melting point, about 183℃, and a high diffusivity. Electromigration has become a reliability issue for eutectic Sn-Pb flip chip packages, when the devices are operated at harsh ambient temperature such as the automotive hood or engine, and even at room temperature.

Advisor

About

C. Robert Kao

Department of Materials Science and Engineering, National Taiwan University

Office : Room 324, Heritage Hall of Physics
Address : No. 1, Sec. 4, Roosevelt Road, Taipei, Taiwan (R.O.C.)
Zip code : 10617
Email : crkao@ntu.edu.tw
Phone : +886-2-3366-3745
Research : 1. 3D IC Integration
2. Microelectronic & Nanoelectronic Packaging
3. Optoelectronic and MEMS Packaging
4. Flip Chip Reliability
5. Solid State Thermodynamics & Solid State Reaction

0 PUBLICATIONS

Web of Science Researcher ID

Education

1994

Doctor of Materials Science

University of Wisconsin

WI, USA

1990

Master of Science in Materials Science and Engineering

Northwestern University

IL, USA

1986

Bachelor of Science in Chemical Engineering

National Taiwan University

Taiwan, ROC

Current Position

Since 2008

Distinguished Professor

National Taiwan University

Department of Materials Science and Engineering

Since 2017

Associate Dean

National Taiwan University

College of Engineering

Since 2003

Principal Editor

Journal of Materials Research

Since 2016

Board of governors

IEEE Electronics Packaging Society

Since 2015

Editor

Journal of Materials Science: Materials in Electronics

Since 2017

Co-convener

Ministry of Science and Technology (MOST)

Material science

Experience

2014-2016

Convener

Ministry of Science and Technology (MOST)

Materials Science and Engineering

2010-2014

Associate editor

Materials Chemistry and Physics

2010-2013

Department Chair

National Taiwan University

Department of Materials Science and Enginnering

2006-2008

Professor

National Taiwan University

Department of Materials Science and Engineering

2006-2010

Independent director

LOTES CO., LTD.

Board of directors

2005-2006

Professor & Chair

National Central University

Graduate Institute of Materials Science & Engineering

1999-2006

Professor

National Central University

Department of Chemical & Materials Engineering

2006

Guest Editor

IEEE

IEEE Transactions on Electronics Packaging Manufacturing

2002-2005

Council Member

The Minerals, Metals & Materials Society (TMS), U.S.A.

The Electronic, Magnetic & Photonic Materials Division

2002-2003

Visiting Professor

University of California - Los Angeles, USA

Department of Materials Science & Engineering

2002-2006

Guest Editor

Journal or Electronic Materials, TMS & IEEE

September Issue, 2001; November Issue, 2002; October Issue, 2003;
December Issue, 2003; October Issue, 2004; October Issue, 2005;
January Issue, 2006; December Issue, 2006.

2001-2004

Advisor

The Minerals, Metals & Materials Society (TMS), U.S.A.

JOM journal

1996-1999

Associate Professor

National Central University

Department of Chemical Engineering

1995-1996

Assistant Professor

National Central University

Department of Chemical Engineering

1994-1995

Research Associate

University of Wisconsin - Madison

Department of Materials Science & Engineering

Advanced Chip Packaging Laboratory

Blog

News

Projects

Research Focus

Flip Chip Package

Lead Free Solder

3D IC

Elecromigration

Advisor

About

C. Robert Kao

Education

Doctor of Materials Science

Master of Science in Materials Science and Engineering

Bachelor of Science in Chemical Engineering

Current Position

Distinguished Professor

Associate Dean

Principal Editor

Board of governors

Editor

Co-convener

Experience

Convener

Associate editor

Department Chair

Professor

Independent director

Professor & Chair

Professor

Guest Editor

Council Member

Visiting Professor

Guest Editor

Advisor

Associate Professor

Assistant Professor

Research Associate

Courses

Physicals of Materials

Numerical Analysis

Materials Science

Microelectronic Package

Thermodynamics of Solids

Consumer Chemistry

Phase Equilibria and Phase Diagrams