+ All Categories
Home > Documents > Self Assembly Nanoscience Education Institute. Making Nanostructures: Nanomanufacturing "Top down"...

Self Assembly Nanoscience Education Institute. Making Nanostructures: Nanomanufacturing "Top down"...

Date post: 20-Jan-2016
Category:
Upload: suzanna-beasley
View: 214 times
Download: 1 times
Share this document with a friend
44
Self Assembly anoscience Education Institute
Transcript
Page 1: Self Assembly Nanoscience Education Institute. Making Nanostructures: Nanomanufacturing "Top down" versus "bottom up" methods Lithography Deposition Etching.

Self Assembly

Nanoscience Education Institute

Page 2: Self Assembly Nanoscience Education Institute. Making Nanostructures: Nanomanufacturing "Top down" versus "bottom up" methods Lithography Deposition Etching.

Making Nanostructures: Nanomanufacturing

"Top down" versus "bottom up" methods

•Lithography•Deposition•Etching•Machining

•Chemical•Self-Assembly

Page 3: Self Assembly Nanoscience Education Institute. Making Nanostructures: Nanomanufacturing "Top down" versus "bottom up" methods Lithography Deposition Etching.

Excerpt from Letter of Benjamin Franklin to William Brownrigg (Nov. 7, 1773)

...At length being at Clapham, where there is, on the Common, a large Pond ... I fetched out a Cruet of Oil, and dropt a little of it on the Water. I saw it spread itself with surprising Swiftness upon the Surface ... the Oil tho' not more than a Tea Spoonful ... which spread amazingly, and extended itself gradually till it reached the Lee Side, making all that Quarter of the Pond, perhaps half an Acre, as smooth as a Looking Glass....

First a case you already know: The nanofilm

Franklin made this observation, but did not determine the thickness.

Page 4: Self Assembly Nanoscience Education Institute. Making Nanostructures: Nanomanufacturing "Top down" versus "bottom up" methods Lithography Deposition Etching.

• The first person to make worthwhile, reproducible measurements on monolayers was Agnes Pockels who lived in Braunschweig, Germany. Agnes Pockels was the original housewife superstar. She performed her first experiments on monolayers in her kitchen in her home, starting in about 1882. She used a tin tray as the water container and a small disk suspended from a balance with a slide weight to measure the surface tension of the water.

• By contaminating the water surfaces with different materials, Pockels created monolayers and observed their properties when confining the water surfaces to various areas using waxed tin strips. Pockels observed that the surface tension of a water surface varies with its size and depends on the type of contamination.

• She sent an account of her work to Lord Rayleigh, who recommended its publication in the journal Nature. Lord Rayleigh had a similar interest in the science of interfaces and was inspired by Pockels to make his own experiments, from which he concluded that these layers were just a single molecule thick.

Agnes Pockels

Page 5: Self Assembly Nanoscience Education Institute. Making Nanostructures: Nanomanufacturing "Top down" versus "bottom up" methods Lithography Deposition Etching.

Langmuir-Blodgett Film

pressuree.g., steric acid

monolayer filmwater

hydrophilic end

hydrophobic end

of an amphiphilicmolecule

Page 6: Self Assembly Nanoscience Education Institute. Making Nanostructures: Nanomanufacturing "Top down" versus "bottom up" methods Lithography Deposition Etching.

The people behind the researchIrving Langmuir Katharine Burr Blodgett

• Nobel prize in chemistry for his work in surface chemistry

• First woman to earn a PhD in Physics from Cambridge University

Performed their research at General Electric in Schenectady, New York

Page 7: Self Assembly Nanoscience Education Institute. Making Nanostructures: Nanomanufacturing "Top down" versus "bottom up" methods Lithography Deposition Etching.

Langmuir-Blodgett Film Transferred to a Solid Surface

Must control movablebarrier to keep constantpressure

multiple dips -multiple layers

solid

liquid

Page 8: Self Assembly Nanoscience Education Institute. Making Nanostructures: Nanomanufacturing "Top down" versus "bottom up" methods Lithography Deposition Etching.

What drives and governs self assembly?

As you view the following images you should consider

the question:

Page 9: Self Assembly Nanoscience Education Institute. Making Nanostructures: Nanomanufacturing "Top down" versus "bottom up" methods Lithography Deposition Etching.

Tobacco Mosaic Virus

wisc.edu

nih.gov

Page 10: Self Assembly Nanoscience Education Institute. Making Nanostructures: Nanomanufacturing "Top down" versus "bottom up" methods Lithography Deposition Etching.

Diatoms

priweb.org

sinancanan.net

Page 11: Self Assembly Nanoscience Education Institute. Making Nanostructures: Nanomanufacturing "Top down" versus "bottom up" methods Lithography Deposition Etching.

Abalone

Page 12: Self Assembly Nanoscience Education Institute. Making Nanostructures: Nanomanufacturing "Top down" versus "bottom up" methods Lithography Deposition Etching.

The Cell and Its Hierarchy

ebi.ac.uk

Page 13: Self Assembly Nanoscience Education Institute. Making Nanostructures: Nanomanufacturing "Top down" versus "bottom up" methods Lithography Deposition Etching.

Gecko feet

Page 14: Self Assembly Nanoscience Education Institute. Making Nanostructures: Nanomanufacturing "Top down" versus "bottom up" methods Lithography Deposition Etching.

Publicity: http://www.sciencedaily.com/releases/2012/01/120125101950.htm

Scorpion Armor

Original article: http://dx.doi.org/10.1021/la203942r

The scorpion a special grooved shield to protect itself against scratches from desert sand. Researchers study this to help develop materials with good erosion resistance for helicopters, pipes, and other applications.

Page 15: Self Assembly Nanoscience Education Institute. Making Nanostructures: Nanomanufacturing "Top down" versus "bottom up" methods Lithography Deposition Etching.

Ultra-tough Shrimp Hammer

The peacock mantis shrimp feasts on snails, crabs and other mollusks and crustaceans by smashing through their shells with its front hammer-like claws, delivering 500 Newtons of force. This is powerful enough to punch through aquarium glass.

Science magazine June 8, 2012 DOI: 10.1126/science.1218764

Page 16: Self Assembly Nanoscience Education Institute. Making Nanostructures: Nanomanufacturing "Top down" versus "bottom up" methods Lithography Deposition Etching.

Whitesides et al. Science 295, 2418 (2002);

Self assembly at all scales?

Page 17: Self Assembly Nanoscience Education Institute. Making Nanostructures: Nanomanufacturing "Top down" versus "bottom up" methods Lithography Deposition Etching.
Page 18: Self Assembly Nanoscience Education Institute. Making Nanostructures: Nanomanufacturing "Top down" versus "bottom up" methods Lithography Deposition Etching.
Page 19: Self Assembly Nanoscience Education Institute. Making Nanostructures: Nanomanufacturing "Top down" versus "bottom up" methods Lithography Deposition Etching.
Page 20: Self Assembly Nanoscience Education Institute. Making Nanostructures: Nanomanufacturing "Top down" versus "bottom up" methods Lithography Deposition Etching.

What enables self assembly?• Static assembly (thermodynamic free energy minimum; requires agitation) -- once formed it is stable• Dynamic assembly (kinetically formed, not necessarily thermodynamic minimum) -- not necessarily stable

• Forces of chemical bonding (4)• covalent, ionic, van derWaals, hydrogen

• Other forces (magnetic, electrostatic, fluidic, ...)• Polar/Nonpolar (hydrophobicity)• Shape (configurational)• Templates (guided self assembly)• Kinetic conditions (e.g., diffusion limited)

Page 21: Self Assembly Nanoscience Education Institute. Making Nanostructures: Nanomanufacturing "Top down" versus "bottom up" methods Lithography Deposition Etching.

SAM: Self Assembled Monolayer

• Chemisorbed molecules• Stabilized by intermolecular van der Waals interaction

solid

moleculesfrom solution

Page 22: Self Assembly Nanoscience Education Institute. Making Nanostructures: Nanomanufacturing "Top down" versus "bottom up" methods Lithography Deposition Etching.

SAM: Self Assembled Monolayer

Review article: J.C. Love, et al., Chem. Rev. 2005, 105, 1103(G. Whitesides group, Chem Dept, Harvard)

HS(CH2)nX alkanethiol on gold (Au)

where X is the end group of the chain –CH3, –OH, or –COOH

Longer alkanethiol molecules have greater thermodynamic stability

Page 23: Self Assembly Nanoscience Education Institute. Making Nanostructures: Nanomanufacturing "Top down" versus "bottom up" methods Lithography Deposition Etching.

SAMs on Nanoparticles

J.C. Love, et al., Chem. Rev. 2005, 105, 1103

gold NP

There are now many configurations and uses of SAMs

imperfect packing

Page 24: Self Assembly Nanoscience Education Institute. Making Nanostructures: Nanomanufacturing "Top down" versus "bottom up" methods Lithography Deposition Etching.

Nanoparticle Monolayer Formed at a Liquid-Air Interface

Page 25: Self Assembly Nanoscience Education Institute. Making Nanostructures: Nanomanufacturing "Top down" versus "bottom up" methods Lithography Deposition Etching.

Nanoparticle Monolayer Formation

Nature Materials MOVIE

toluene

Requirements:• rapid evaporation• excess dodecane present• attractive interation to liq-air interface and between particles

Page 26: Self Assembly Nanoscience Education Institute. Making Nanostructures: Nanomanufacturing "Top down" versus "bottom up" methods Lithography Deposition Etching.

SELF ASSEMBLY with DIBLOCK COPOLYMERS

Block “A ” Block “B”

10% A 30% A 50% A 70% A 90% A

~10 nm

Ordered Phases

PMMA PS

Scale set by molecular size

Page 27: Self Assembly Nanoscience Education Institute. Making Nanostructures: Nanomanufacturing "Top down" versus "bottom up" methods Lithography Deposition Etching.

CORE CONCEPT FOR NANOFABRICATION Deposition

Template

EtchingMask

NanoporousMembrane

Remove polymerblock within cylinders(expose and develop)

Versatile, self-assembling, nanoscale lithographic system

(physical orelectrochemical)

Page 28: Self Assembly Nanoscience Education Institute. Making Nanostructures: Nanomanufacturing "Top down" versus "bottom up" methods Lithography Deposition Etching.

Array Period = 24 nm Pore Diameter = 14 nm

MW = 42,000PS/PMMA

TEMPLATE CHARACTERIZATION

100 cpp

SEMSAXS

Page 29: Self Assembly Nanoscience Education Institute. Making Nanostructures: Nanomanufacturing "Top down" versus "bottom up" methods Lithography Deposition Etching.

Improving Order: Guided Assembly in a Trench: Graphioepitaxy

UMass-Seagate

assemble here

side view

top

view

Page 30: Self Assembly Nanoscience Education Institute. Making Nanostructures: Nanomanufacturing "Top down" versus "bottom up" methods Lithography Deposition Etching.

nanoporous template

Nanomagnets in a Self-Assembled Polymer Mask

1x1012 magnets/in2

Data Storage......and More

Page 31: Self Assembly Nanoscience Education Institute. Making Nanostructures: Nanomanufacturing "Top down" versus "bottom up" methods Lithography Deposition Etching.

Metal Nanorings

Ferromagnetic cobalt rings as small as 15 nm OD

Page 32: Self Assembly Nanoscience Education Institute. Making Nanostructures: Nanomanufacturing "Top down" versus "bottom up" methods Lithography Deposition Etching.

Mohan Srinivasarao, et al. Science 292, 79 (2001).

Kinetic Self-Assembly - by Breath Figures

Polystyrene Film

Page 33: Self Assembly Nanoscience Education Institute. Making Nanostructures: Nanomanufacturing "Top down" versus "bottom up" methods Lithography Deposition Etching.

More Fabrication by Breath Figures

UMass: Alexander Böker, Yao Lin, Kristen Chiapperini, Reina Horowitz, Mike Thompson, Vincent Carreon, Ting Xu, Clarissa Abetz, Habib Skaff, A. D. Dinsmore, Todd Emrick and Thomas P. Russell, Nature Materials 3, 302 - 306 (2004)

a, Breath-figure pattern obtained with pure polystyrene. b, Optical and c, confocal fluorescence microscope images of different areas of a sample obtained from solvent-casting a polystyrene film from chloroform with CdSe nanoparticles. Scale bars: 16 mum. The inset in c shows a fluorescence intensity scan along the line indicated.

Page 34: Self Assembly Nanoscience Education Institute. Making Nanostructures: Nanomanufacturing "Top down" versus "bottom up" methods Lithography Deposition Etching.

Anodized Aluminum Oxide Templates

Aluminum

Nanoporousaluminum

oxide (AAO)~ 40 V

counter electrode

Anodization Acid Bath

I

e.g., • Keller, et al., J. Electrochem. Soc. 100, 411 (1953) • Masuda & Fukuda, Science 268, 1466 (1995)

(oxalic, sulfuric, orphosphoric acid)

Masuda, et al.

Page 35: Self Assembly Nanoscience Education Institute. Making Nanostructures: Nanomanufacturing "Top down" versus "bottom up" methods Lithography Deposition Etching.

Proposed AAO Growth Mechanism

Figure adapted fromJessensky, Müller, & Gösele, Appl. Phys. Lett. 72, 1173 (1998)

Al2O3

E

Al

Al3+ O2-

• Density mismatch between Al and Al2O3

• Some Al3+ goes to solution

• Mechanical stress yields pore growth in uniform hexagonal array

Pore diameters of ~ 10-400 nm possibleby choice of anodizationconditions

Page 36: Self Assembly Nanoscience Education Institute. Making Nanostructures: Nanomanufacturing "Top down" versus "bottom up" methods Lithography Deposition Etching.

Improving AAO Order at Surface

SiC stamp

Aluminum

anodize

e.g., Masuda et al., Appl. Phys. Lett 71, 2770 (1997);Choi, et al., J. Vac. Sci. Tech. B 21, 763 (2003)

Page 37: Self Assembly Nanoscience Education Institute. Making Nanostructures: Nanomanufacturing "Top down" versus "bottom up" methods Lithography Deposition Etching.

Molecular Recognition("lock and key" bonding)

biotin-avidin pair (site-specific binding)thymine (T) adenine (A)

guanine (G) cytosine (C)

hydrogen bonding

Page 38: Self Assembly Nanoscience Education Institute. Making Nanostructures: Nanomanufacturing "Top down" versus "bottom up" methods Lithography Deposition Etching.

Using Synthetic DNA for Designer Structures

Ned Seeman, NYU

Designer DNA molecules can be synthesized chemically, and allowed to assemble into a specific configuration of lowest energy.

Page 39: Self Assembly Nanoscience Education Institute. Making Nanostructures: Nanomanufacturing "Top down" versus "bottom up" methods Lithography Deposition Etching.

Programmed DNA Folding to Make "DNA Origami"P.W.K. Rothemund, Nature 440, 297 (2006)

Page 40: Self Assembly Nanoscience Education Institute. Making Nanostructures: Nanomanufacturing "Top down" versus "bottom up" methods Lithography Deposition Etching.

Programmed DNA Folding: Advanced DesignsWilliam Shih, Harvard University

Page 41: Self Assembly Nanoscience Education Institute. Making Nanostructures: Nanomanufacturing "Top down" versus "bottom up" methods Lithography Deposition Etching.

Microfluidic Assembly

Application: RFID

Alien Technology

Nanoscale Phase SeparationIBM "air gap" technology

Introducing nanoscale air pockets into the insulating material separating wires on a computer chip -- lowers the capacitance

flow direction

Parts, having unique shape, are delivered via fluid flow to mating pockets on an assembly substrate.

Page 42: Self Assembly Nanoscience Education Institute. Making Nanostructures: Nanomanufacturing "Top down" versus "bottom up" methods Lithography Deposition Etching.

NEW! Self-Folding Objects

https://www.youtube.com/watch?v=NKRWZG67dtQ http://www.prism-magazine.org/jan13/feature_01.cfm

Page 43: Self Assembly Nanoscience Education Institute. Making Nanostructures: Nanomanufacturing "Top down" versus "bottom up" methods Lithography Deposition Etching.

Large Scale Self-Assembly (Geological)

Giant's Causeway(Northern Ireland)

Volcanic basalt cooled rapidly to form these (mostly) hexagonally shaped columns

Page 44: Self Assembly Nanoscience Education Institute. Making Nanostructures: Nanomanufacturing "Top down" versus "bottom up" methods Lithography Deposition Etching.

Explore concepts of self assembly in the classroom

• Balls in a box (best packing)• Straws or toothpicks in a container (lattice and defects)• How shape influences packing density and the symmetry of assembled structures• Objects floating on water (Cheerios and other shapes)• Two-dimensional array of magnets; floating magnets - attractive and repulsive cases• Crystallization - explore how conditions influence size and perfection of crystals

Underlying principles: forces (non-directional or directional), shape, thermal agitation


Recommended