int a nanomecanica

int a nanomecanica

(Parte 1 de 2)

3.052 Nanomechanics of Materials and Biomaterials 02/06/06 Prof. C. Ortiz, MIT-DMSE I

LECTURE 1 : INTRODUCTION TO NANOMECHANICS

NANOTECHNOLOGY / NANOM ECHANICS DEFINITIONS2
WHY IS NANO I NTERESTI N G?3
HISTORY OF NANOTECHNOLOGY/NANOMECHANICS : TIME LINE4
The First Talk on Nanotechnology: "There's Plenty of Room at the Bottom" - Richard Feynman (1959)5
Moving Individual Atom s with the Scanning Tunneling Microscope - Don Eigler (1990)6
Imaging Individual Biomacromolecules with the Atomic Force Microscope (2003)7
Dip Pen Nanolithography : "There's Plenty of Room at the Bottom" - 40 years later-Chad Mirkin (1999)8
NANOFABRICATION /NANOSTRUCTURED MATERIALS: "BOTTOM-UP" vs. "TOP-DOWN"9
NANOMECHANICS10
Concept of a Continuum10
Subcategories : Contact vs. Noncontact1

Outline : Objectives: To establish the terminology, history, broad concepts, and motivation for course

Readings: Course Reader Documents 1-5

Multimedia : Listen to "Tiny Machines" by Richard Feynman, plus Introduction mp3 by Prof. Ortiz

3.052 Nanomechanics of Materials and Biomaterials 02/06/06 Prof. C. Ortiz, MIT-DMSE

Nanotechnology : "Νανο" derives from the Greek word for dwarf. Technologies dealing with characteristic length scales 1-100 nanometer (1 nm) = 1*10 -9 m (one billionth of a meter)

→atoms molecules, cells.

FactorSy mb olPrefi x p n m c k M G atto pi co nan o mi cro milli ce nti kilo mega gi ga FactorSy mb olPrefi x p n m c k M G atto pi co nan o mi cro milli ce nti kilo mega gi ga

Molecular Manufacturing / Nanofabrication : Fabrication / modification of structures with nm-scale precision

Nanomechanics: Subset of the field of nanotechnology involving nN-scale forces or nm-scale displacements Nanostructured Materials : materials where fundamental constituents are nm-sized

Less than a nanometer : individual atoms are up to a few angstroms or up to a few tenths of a nanometer in diameter

Thousands of nanometers :

Biological cells, like red blood cells, have diameters in this range

One nanometer :

Ten shoulder-to-shoulder hydrogen atoms (blue balls) span 1 nanometer. DNA molecules are ~ 2.5

Billions of nanometers : A two meter tall male

A Million nanometers : The pinhead sized patch of this thumb (circled in black)

Adapted from a Report by the National Science and

Technology Council (NSTC) Committee on Technology,

The Interagency Working Group on Nanoscience, Engineering and Technology (IWGN) (1999)

3.052 Nanomechanics of Materials and Biomaterials 02/06/06 Prof. C. Ortiz, MIT-DMSE WHY IS NANO INTERESTING?

1) Design scale of nature → atoms, proteins, molecules; origins of disease "bio-nano" - can interface with biology

2) Size-dependent nonscalable properties 3) Unique properties

3.052 Nanomechanics of Materials and Biomaterials 02/06/06 Prof. C. Ortiz, MIT-DMSE

• Democritus in ancient Greece: concept of atom • 1900 : Rutherford : discovery of atomic nucleus

• 1959 : Richard Feynman : speech at Caltech "There is plenty of room at the bottom" • 1969 : Invention of Surface Forces Apparatus (SFA)

• 1981 : Invention of the Scanning Tunneling Microscope (STM) by Rohrer and Binnig at IBM Zurich (Nobel Prize 1986) • 1982 : First STM atomic resolution by Binnig on Si 7x7

• 1985 : Fullerene " buckyballs" discovered at Rice University (Nobel prize awarded in 1996) • 1986 : Invention of Atomic Force Microscope (AFM) by Binnig, Gerber, and

Quate,measurement of 10 -12 N forces, K. Eric Drexler "Engines of Creation"-

Molecular manufacturing; bottom up & self-assembly and self-replicate, "grey-goo" • 1989 : Invention of Optical Tweezers, first commercially available microfabricated cantilevers for AFMs

• 1990 : First commercially available AFMs, Eigler, et al. spells out "IBM" with Xenon atoms

• 1992 : First single molecule force spectroscopy experiments (DNA, Bustamante)

• 2000 : President Clinton mentions Nanotechnology in his state of the Union address : US National Nanotechnology Initiative since 2000 (14 federal agencies) -$422 M in ’01 (federal), $604 M in ’02, $774 M in ’03, $847 M in ’04 21 Federal agencies • 2004 : Journals: Nanotechnology, Nano Letters, Journal of Nanoscience and Nanotechnology, IEEE Transactions on Nanotechnology, IEEE Transactions on Nanobioscience

3.052 Nanomechanics of Materials and Biomaterials 02/06/06 Prof. C. Ortiz, MIT-DMSE

"There's Plenty of Room at the Bottom" (1959)

Richard P. Feynman December 29th 1959 (41 y.o.) American Physical Society Meeting (CalTech) : theoretical physicist

"Nanotech Prophet"

-enormous amounts of information can be carried in an exceedingly small space

-scaling down devices requires new designs and does not violate any fundamental laws of physics; look at biology

- army of "slave hands" : nanomanipulators

-"physical synthesis" as opposed to "chemical synthesis"

Challenges : miniaturization of the computer, direct visualization at the nanoscale, Encyclopedia Brittanica on the head of a pin, construct a 1/64 cubic inch motor

Multimedia : Watch the movie "Tiny Machines" by Richard Feynman (1988)

Cool book to read "Surely You're Joking Mr. Feynman"

Image removed due to copyright restrictions. Portrait photo of Richard Feynman playing bongo drums.

3.052 Nanomechanics of Materials and Biomaterials 02/06/06 Prof. C. Ortiz, MIT-DMSE

MICROSCOPE (STM)- 30 Years after Feynaman (1990) D. M. Eigler & E. K. Schweizer IBM Almaden (NATURE VOL 344 5 APRIL 1990)

Move and position individual atoms on a metal surface using a scanning tunneling microscope tip. Writing one atom at a time with Xe atoms on a Ni (110) surface, IBM scientists could actually fit the Encyclopedia Brittanica on a space the size of a pin head. The STM microscope was cooled to 4 K, in an ultra-high -vacuum system, and the STM tip speed was 0.4 nm/sec. At that speed they could have completed the job in about 87,0 years.

- The challenge is how to build macroscopic structures in a reasonable time frame and how to make functional structures.

(Parte 1 de 2)

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