In this paper recently feature on the cover of Science Translational Medicine, we report the development of a class of mechanically flexible silicon electronics for multiplexed measurement of signals in an intimate, conformal integrated mode on the dynamic, three-dimensional surfaces of soft tissues in the human body. Mechanics model shows that the strain in the fragile materials, e.g. silicon, is several orders of magnitude smaller than the fracture strain, when wrapped onto the curvilinear cardiac surface.

Call for papers

2009 MRS Spring Meeting, San Francisco, CA, April 13-17

Symposium PP: Materials and Devices for Flexible and Stretchable Electronics

Abstract Deadline: 3 November 2008

www.mrs.org/spring2009

In this paper, we report comprehensive experimental and theoretical
studies of bending in structures relevant to inorganic flexible electronics.
Different from previous mechanics models of related systems, our analysis does not
assume the thin film to cover the entire substrate, thereby explicitly
accounting for effects of edges and finite device sizes, both of which play
critically important roles in the mechanics and bending properties. These
thin-film islands give nonuniform stress, with maxima that often appear at the
edges and spatially non-uniform shear and normal stresses along the film/substrate
interface. Although these results are generally applicable to all classes of

H. Mei, Y. Pang, and R. Huang, International Journal of Fracture 148, 331-342 (2007).

Following a previous effort published in MRS Proceedings, we wrote a journal article of the same title, with more numerical results. While the main conclusions stay the same, a few subtle points are noted in this paper.

First, instead of using the approximate formula by Ye, Suo and Evans (1992), we calculate the energy release rate of interfacial delamination emanating from the channel crack exclusively by the finite element method. We found that the approximate formula is not accurate in several cases.

Attached slides were presented at the 2007 ASME Congress at Seattle.

I attach slides for an ASME talk, which is based on a recent paper.

A 1um-thick Cu film was deposited on Kapton 50HN substrate, with a thin Cr interlayer to improve adhesion. The specimen was in-situ annealed at 200oC for 30min after deposition.

This FIB image was taken after the specimen was uniaxially stretched to 50% and released.

A link for the paper: http://www.seas.harvard.edu/suo/papers/201.pdf

This is a winning entry in the Sci/Terp Video Competition at University of Maryland (UMD).

Hi, I'm a Physics grad student working with Dr. Ellen Williams. My job is basically making nanoelectronic devices, measuring their characteristics and trying to understand the underlying "Physics".

What I want to gain from this course is to come to know how flexible macroelectronics are approached and researched. An increasing trend of "thin" applications poses new challenges in terms of low power usage and durability.

My name is Daniel Min.  I am a senior mechanical engineering student at the University of Maryland.  I am currently enrolled in Dr. Teng Li's flexible macroelectronics course.  I chose to enrol

I am Yong Wang, currently a PhD student in the Mechanical Engineering department at the University of Maryland. I got my Bachelor degree from the University of Science and Technology of China and Master degree from the Hong Kong University of Science and Technology. I am enrolled in Dr. Teng Li's class on flexible macroelectronics in this semester.

My name is Kurt Vargas. I am an international student from Costa Rica, currently attending the University of Maryland at College Park. I am a Christian who loves the Lord and serves Him full time. I also love reading my Bible!

My name is Adam Rutherford and I am currently a senior mechanical engineering student at the University of Maryland. I am enrolled in Dr. Teng Li's class on flexible macroelectronics. I chose this course out of the selection of electives because I feel that flexible macroelectronics will have a large impact on the consumer electronics industry in the near future.

My name is Navid Charooseh and I am a senior undergraduate student at the University of Maryland. I currently work for Dr. Yu in the Sensors and Actuators Laboratory. My interests include biomechanics, bio-inspired engineering, and devices (sensors, etc) to be used in biological applications.

My name is Josh Crone and I am an undergraduate student in Mechanical Engineering at the University of Maryland. I am in the BS/MS program with a focus in mechanics and materials. My current research interests are in atomic force microscopy.

My name is Nathan and I am a Masters student in my second year at the University of Maryland, College Park studying mechanical engineering.  I was born and raised in Erie, PA.  For my undergraduate studies, I attended the University of Pittsburgh in Pittsburgh, PA where I also studied mechanical engineering.  When I am not engineering, I enjoy running, playing the piano, and following the stock market. 

My name is Dan Forrest and I am currently a biological resources engineering student at the University of Maryland. I am taking ENME489X: Flexible Macroelectronics to fulfill a degree requirement. However, I chose this specific class because the topic in general seemed interesting to me and appears to be an up and coming field in the electronics industry.

My name is Anand Pillarisetti. I am a graduate research assistant at University of Maryland, working towards my doctoral degree in mechanical engineering. I received Master of Science (MS) degree in mechanical engineering and mechanics from Drexel University, Philadelphia, PA and Bachelor of Technology (B-Tech) degree in mechanical engineering from National Institute of Technology (NIT), Warangal, India.  I am currently enrolled in the course "Flexible Macroelectronics" taught by Dr. Teng Li at University of Maryland.

My name is Hongbo Bi and I am a Ph.D candidate in Mechanical Engineering under Dr. Bongtae Han at the University of Maryland, College Park. I recieved Master of Science (M.S.) degree in Mechanical Engineering from University of Maryland, College Park and and Bachelor of Engineering (B.E.) in Automatic Control from University of Science and Technology of China. I am currently entrolled into class of Flexible Macroelectronics (ENME808H) at the University of Maryland, which is taught by Prof. Teng Li.

My name is Daniel Kodan, I am an undergraduate Mechanical Engineering student at the University of Maryland.  I am currently taking a flexible macroelectronics class taught by Dr. Teng Li.  I am

Hi my name is Gary Palmer II and I'm a senior mechanical engineering major at the University of Maryland. My interest in flexible macroelectronics stems from its future capabilities. The fact that these components can be integrated with everyday objects is fascinating. Since this technology will be used in the future, it will be great to be on the leading edge of its development.

My name is Christi Ryon. I am a senior undergraduate mechanical engineering student at the University of Maryland, College Park. I am taking a course in flexible macroelectronics for two reasons. First, this course fulfils a major requirement. The second reason is that the subject of flexible macroelectronics is a new emerging technology that I was not familiar with but is a topic that I wished to learn more about.

My name is Ben Marshall and I am an undergraduate mechanical engineering student at the University of Maryland.