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Robert W. CohnElectroOptics Research Institute
& Nanotechnology CenterUniversity of Louisville
* With apologies to similarly titled books by R.P. Feynman and R. Fulghum
Good and bad definitions of nanotechnology
Is there still plenty of room at the bottom? Current limits to seeing and manipulating atoms
Some practical limits to nanodevice fabrication
Examples of nanotechniques that make research easier rather than harder
Conclusion: The lasting effects of nanotechnology
�The emerging fields of nanoscale science, engineering, and technology - the ability to work at the molecular level, atom by atom, to create large structures with fundamentally new properties and functions - are leading to unprecedented understanding and control over the basic building blocks and properties of all natural and man-made things.� M.C. Roco, NSF
�Much of nanoscience is, however, done in university laboratories, and a scanning probe microscope that is local probably has more impact on the rate of progress of the field than an electron microscope located in a different state.�
G.M. Whitesides, Harvard U.
�I find that the very term �nanotechnology� � although wonderfully suited to the description of a welcome and significant funding initiative � is at too high a level of abstraction for our purposes here today. Which �nanotechnology� are we supposed to be talking about?� J.A. Armstrong, IBM
�Nanotechnology is what I do.� S.M. Block, Stanford U.
�... a lot of resources go into the re-presentation and re-labeling of ongoing work, which nevertheless remains very much the same ...� H. Glimell, Göteborg U.
�Nanotechnology Spans the Conventional Disciplines. .... Scientists and engineers developing nanoscience and technology will have to be aware of a broader and different range of subjects than those included in the usual departmental curricula.� G.M. Whitesides, Harvard U.
�Unfortunately our engineering education system is not geared, for the most part, to teaching a unified approach to understanding and using science. ... Developing a broadly trained and educated workforcepresents a severe challenge to our four-year degree and two-year degree educational systems, which favor compartmentalized learning.�
S.J. Fonash, Penn State U.
�There is a long heritage within academia of the single discipline as the core entity of organization. Even in areas where external forces have exerted strong pressure to transcend them, disciplines have proven amazingly persistent.� H. Glimell, Göteborg U.
Use nanotechnology as a tonic that develops interdisciplinarity
SIZE COMPARISON OF BIOMATERIALS,ELECTRONICS & THE THREE BEAMS
S. Asai and Y. Wada,Proc. IEEE, April 1997
IMAGING ATOMIC STRUCTURE
Transmission ElectronMicrograph
by E. C. DickeyUniversity of Kentucky
ELECTRON STANDING WAVE ELECTRON MIRAGE
Don Eigler Group, IBM (see Nature 2/3/00)
Chemistry, molecular biology and mechanics merge at the nanoscale
4 nm
THE KINESIN MOTOR PROTEIN
Vale & Milligan Science (4/7/00)
Measures force applied by
kinesin
Has been used to unwrap folded
molecules
Motor proteins have been attached to
silicon propellers
Steven Block,Stanford
E-beam written guitar strings are 50 nanometer diameterCornell National Nanofabrication Users Facility, Laser Focus 9/97
WRITING SPEED versus RESOLUTIONFOR VARIOUS PATTERNING METHODS
S. Matsui, Proc.IEEE, April 1997
The tip is 6 �m long with a 20 nm tip radius
1 �m100 nm
Hong &Mirkin,
Northwestern
Silicon dioxide line on silicon written & profiled by AFMElectron beams also will directly oxidize silicon
Produced by chemical etching of AFM written lines
54 nmX
690 nm340 nm
in x and z
340 nmin x and z
200 nm
200 nm 30 nm
200 nm
200 nm 30 nm
15 nm
15 nm
15 nm
15 nm
AFM oxidized lines on nitrogen-passivated siliconare wet etched to produce vertical, sub-15 nm trenches
Gil Lee, Purdue & NRL
Forcedetection
of DNA
THE MICROFABRICATED BIOCAPSULENANOPORE MEMBRANE
ENCAPSULATEDCELLS
INSULIN
IMMUNOGLOBULINSNUTRIENTS
Mauro Ferrari,Ohio State
SILICONTO
SILICONBONDING
P+ poly-Si
P+ Si
Silicon
Thin oxide
After oxide etch the sidewall coating givesnanometer thick, microns in length pores
M. Ferrari,Ohio State
Nano-methods are quickly being adopted by academic institutions worldwide because of their ease of use and low cost
The interdisciplinarity of nanoscience requires and motivates improved learning, retention and creative application of the fundamentals of science
�Wisdom is not at the top of the graduate school mountain,but there in the sandpile �� R. Fulgham
�Be aware of wonder.� R. Fulgham
�� it might be just for fun.� R.P. Feynman
Surely you're joking, Mr. Feynman that "All I really needed to know (about nanotech)
I learned in kindergarten"
�Warm cookies and milk are good for you.� R. Fulgham
(not shown at talk)
From "All I Really Need to Know I Learned in Kindergarten�Robert Fulghum
All I really need to know about how to live and what to do and how to be I learned in Kindergarten. Wisdom is not at the top of the graduate school mountain, but there in thesandpile...Share everything.Play fair. Don't hit people.Put things back where you found them. Clean up your own mess.Don't take things that aren't yours.Say you're sorry when you hurt somebody.Wash your hands before you eat. Flush.Warm cookies and cold milk are good for you.Live a balanced life - learn some and think some and draw and paint and sing and dance and play and work every day some.Take a nap every afternoon.When you go out into the world, watch out for traffic, hold hands, and stick together.Be aware of wonder.And remember the Dick-and-Jane books and the first word you learned - the biggest word of all - LOOK.
SiO2 line on (110) siliconwritten & profiled by AFM
Vertical nanostructures byTMAH etch of SiO2 lines
Concept for WDM multibandfilter by AFM lithography
THE 3D NANOSCALE IMAGING FACILITYECS-9724371: MRI grant to R. W. Cohn et al., U. Louisville
10 �m
25 �m
25nm
1 1 -1 0 1 1
� ��� �� �
� ��� �
� �
85 nm
1 nm
Goal: Locate complementary microscopes in one facility for materials & devices faculty: AFM & Wyko optical profiler from NSF + SEM from UofL.Results: Started new research studies in nanofabrication (see figs below)Delivered new course Nanotechnology: Survey & Lab Practice (Sp�2000)
340 nm(in x and z)
54x
690nm
200 nm
30 nm
15 nm340 nm
(in x and z)2D grating
by AFM
AFMtrenches
on nitridedsilicon
aperiodicproposed
periodic
aperiodicgeneral
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1 1 1 0 0 -1 -1 1 1
�����
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� ��
���
�
1 1 1 1 1 1 1 1 1
��
�����
����
�
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�
magnitudes: 1 1 .1 .2 1 .1 .3 1 1phases: �0o
�20o�0o-80o 0o
�40o 0o�30o 0o
GENERALIZED GRATING FILTERSMADE POSSIBLE BY NANOLITHOGRAPHY
Stripes positioned every �����
Strip
e re
flect
ivty
1�s
0�s
-1�s
Desired & approximated impulse response
Fourier spectra from desired & approximated functions
Wavelength (nm)W
avel
engt
h re
flect
ivity
(db)
633 640 647
0
-10
-20
-30
-40
GRATING FILTER DESIGNUSING REFLECTIVITIES 1, 0, -1
3 nm thick SiO lines on silicon written by AFMfollowed by anisotropic vertical etching
10 �m
25 �m
25 n
m
1 1 -1 0 1 1
� ��� �� �
� ��� �
� �
VERTICAL ETCH PLANES ON [110] SILICON
With KOH {110} plane etches 120X faster than the {111} planeResist lines in the {111} directions define vertical ridges
{100}{111} {111}