1. Lecture 1 Fundamentals of Multiscale Fabrication
Introduction to multiscale fabrication:
From historical background to current research
Kahp-Yang Suh
Associate Professor
SNU MAE

2. Introduction to multiscale systems
Paradigm shift to nano/micro/macro multiscale design and manufacturing
Figure 1. New paradigm of multiscale design and manufacturing for next generation automobile

3. Introduction to multiscale systems
Why multiscale problems important?
Limitations of engineering design based on continuum mechanics
Micro/Nanoscale issues from physics/chemistry/materials
System integration and bridging among nano/micro/macro-scales
Electronic packaging
Molecule model
Bridging model
Finite element model
Figure 2. Various engineering problems for multiscale design and manufacturing

4. Introduction to multiscale systems
Recent trends
Academic interests explode:
44% of journal papers have been published for the last three years during
Among papers published during , mechanical engineering takes up more than 60%!
Many engineering research institutes:
Center for integrative Multiscale Modeling and Simulation (CalTech)
Multiscale Science and Engineering Center (Rensselaer Polytechnic Institute)
Center for Multiscale Modeling for Engineering Materials (Carnegie Mellon)
Multiscale Engineering Classes at Stanford & MIT
ex) MIT open course ware:
2004/CourseHome/index.htm
Center for Multiscale Mechanics and Mechanical Systems (Keio Univ)
Department of Multiscale Physics (Delft Univ)
Center for Multiscale Design, WCU program, MAE, Seoul National University
Biomimetic Mechanical Systems, IAMD, Seoul National University

5. National Science and Technology Council 1999
The History of Miniaturization
There’s Plenty of Room at the Bottom
Richard Feynmann (1959)
“Why cannot we write the entire 24 volumes of the Encyclopedia Britannica on the head of a pin? ”
National Science and Technology Council 1999

6. The History of Miniaturization
- 1943
ENIAC: The first electronic computer (general purpose)
US Army: US$500,000
Over 30 tons, 19,000 vacuum tubes, 1,500 relays, 200 KW
- 1947
The First Transistor: Bell Lab
Nobel Prize (Bardeen, Brattain, & Shockley)
Intel Corp. (Shockley)
- 1958!
The first Integrated circuit
Jack Kilby (Texas Instrument)
Five transistors
Half an inch long and
Thinner than a toothpick.
- 1998: Intel Pentium III > 500MHz, 0.2  technology,
~ 1 million transistors

7. Near Future Molectronics? High Speed, Low Power, Small Size
Moor’s law? – 2 times every 18 months…

8. Standard Decimal Prefixes
Multiplier Prefix Abbreviation Size examples (in meter)
1012 tera T ?
109 giga G Sun
106 mega M Earth
103 kilo k
Animals
10-1 deci d
10-2 centi c Ant
10-3 milli m frog egg
paramecium
eukaryotic cells
bacteria
10-6 micro  CMOS
nanotubes, proteins
10-9 nano n molecules
pico p ?
femto f
atto a
zepto z

9. What size are we talking about?
Adapted from Biology, N.A. Campbell

10. Fabrication methods Top-down approach Bottom-up approach Bulk
Atom, molecule

11. Bottom-up approaches Bottom Up Approach – Molecular Manufacturing
Start at the atomic/molecular level and construct nano-devices by combining and manipulating molecules together
Manufacture every atom or molecule perfectly into place
More complex and efficient
More time consuming
This approach is less
mature than Top-Down
Self-Assembled Product
Creates
Plus
Tools
Materials with stored information

12. Top-down approaches Top down Approach – Mold/Master Replication
Transfer the pattern of a master or mold onto a substrate by various physical/chemical/ optical/electrical principles.
Beautiful mother -> Beautiful daughter
(it is true!)
Parallel vs. serial process
More precise and controllable
More money consuming
This approach is more
mature than Bottom-Up
IBM Cu interconnect
The smallest Guitar produced by state-of-the-art lithography technique. Thickness of the string is 50 nm, and the sound frequency is 10 MHz.

13. Top-down vs. Bottom-up
Fabrication gray zone (10 ~ 50 nm)