NANOSCALE OPTICAL METROLOGY ANDCHARACTERIZATION

The Institute of Optics, University of Rochester, Rochester, NY, 14627.

Lukas Novotny

OUTLINE

2. NANOSCALE METROLOGY

- general thoughts - requirements for nanoscience/technology

1. BACKGROUND (NANO-OPTICS)

3. EXAMPLES

- nanoscale subsurface spectroscopy and imaging

Concentrate on R and not D ! -> D builds on R

Basic Sciences Optics Technical Sciences

NanotechnologyNanoscience

. . . . . .

NANO-OPTICS . . . . . .

Nano-Optics is the study of optical phenomena and techniques near or beyond the diffraction limit.

THINGS ARE GETTING SMALLER . . .

WHAT ARE THE OPPORTUNITIES FOROPTICS ?

nano-optics

WHY NANO – OPTICS ?

F

nanoscale manipulation

V(S/N)

nanoscale probing

h x

nanoscale spectroscopy

CHEMICAL VS. SPATIAL INFORMATION

NSOM

Spatial Resolution

Ch

em

ical

Info

rma

tio

n

1 nm 1 m 1mm

low

ato

mic

mo

lecu

lar

NMR- IR

-Raman

SPM

ElectronMicroscopy

Ion microscopy

X-Rays

DielectricAnalysis

S. Stranick, NIST

proteins quantum states

TWO IMPORTANT LENGTH-SCALES

“New Truths become evident when new tools become available”

(Rosalyn Yalow)

New instrumentation catalyzes new discoveries

STRUCTURE OF DNA

Bragg diffraction, 1912 X-ray diffraction of DNA Structure of DNA,1953

CELL STRUCTURE / FUNCTION

Leeuwenhoek, 1680

“The rapid advances of nanoscience and nanotechnology are due in large part to our newly acquired ability to measure and manipulate individual structureson the nanoscale.” (Nanoscience & Nanotechnology Initiative)

STM AFM

NSOM

Single Molecule

Spectroscopy

OpticalTweezers

1982

1986

1986

1994

2001

NNI

1996

NF

P36

NATIONAL NANOTECHNOLOGY INITIATIVE

NANOMATERIALS

TEM, 1931 (Knoll & Ruska)

Carbon nanotubes, 1991 (Iijima)

NANOSCIENCE / NANOTECHNOLOGY

STM, 1982 atomic manipulation, 1993

NANOBIOTECHNOLOGY

AFM, 1986

Membrane proteins, 1994

Cantilever array sensors, 1998

ADVANCES ININSTRUMENTATION

(microscopy, spectroscopy, .. )

ADVANCES INSCIENCE

(new principles, .. )

ADVANCES INTECHNOLOGY

(fabrication, materials, .. )

INSTRUMENTATION – RESEARCH – TECHNOLOGYCYCLE

WHAT’S FIRST (egg or hen) ? INSTRUMENTATION (need input to think)

Challenge #1:Demand in nanoscale subsurface imaging and characterization

Many future nanoscale devices and components need to be protected from interactions with the environment !

Current high-resolution techniques are surface specific (STM, AFM, EM, .. )

NANOSCALE INSTRUMENTATION & METROLOGY

NNI GRAND CHALLENGE #4 :

Si capping layer

Challenge #2:Demand in minimally invasive nanoscale instrumentation

Wer misst, misst MIST !

Measurement artifacts !

(any measurement is a perturbation to the system to be measured)

NANOSCALE INSTRUMENTATION & METROLOGY

NNI GRAND CHALLENGE #4 :

Molecule + Electrode problem (-> Duncan Stewart)

NANOSCALE INSTRUMENTATION & METROLOGY

NNI GRAND CHALLENGE #4 :

Challenge #3:Demand in chemically specific nanoscale instrumentation

What are we measuring ?

(interpretation of measurements often relies on prior information)

Microscopy & Spectroscopy

spatial resolution chemical specificity

Materials have transparent spectral windows -> subsurface imaging

Light-matter interaction is chemically specific -> spectroscopy

Resolution -> challenged by diffraction

No mechanical contact -> non-invasive

LIGHT

THE DIFFRACTION CHALLENGE

D.W. Pohl et al., Appl.Phys.Lett. 44, 651 (1984)

E.H. Synge, Phil.Mag. 6, 356 (1928)E. Abbe, Arch. Mikrosk. Anat. 9, 413 (1873)

Increasing numerical aperture

Example #1: 4Pi Confocal Fluorescence Microscopy

S. Hell, MPI Goettingen

conventional subsurface imaging

Example #2: Numerical Aperture Increasing Lens (NAIL)

S. Unlu & B. Goldberg, Boston University

with NAIL

10 m

conventional subsurface imaging

Thermal Imaging with NAIL

S. Unlu & B. Goldberg, Boston University

with NAIL

mirrorSi

Example #3: Spectral Self-Interference Microscopy

B. Goldberg, Boston University

SiO2

wavenumber 1/ (cm-1)

17000 18000 19000 20000

(nm

)

position on sample (mm)

0

2

4

6

8

10

0.0 2.0 4.0 6.0 8.0 10.0

top

bottom

Lipid Bilayer

Example #3: Near-field Optical Spectroscopy

Ultramicroscopy 71, 21, (1998).

N

o No

ULTRASHARP PROBES

Standard Optical Microscopy: Near-Field Raman Microscopy: Vibrational Spectrum:

Carbon Nanotubes

topography Raman scattering line-scan

PRL 90, 95503 (2003)

Carbon Nanotubes

Electrical Measurements: Materials Performance - electronic response mapping (µW, rf and dc). - tunneling and resonance spectroscopies

Vis/IR illumination: Chemical Properties - local field enhanced IR absorption/Raman scattering. - probes local chemical functionality/structure.

Sample

Localized Field

electrical

Vis/IR

Chemical Properties

MULTITASKING / MULTISPECTRALNANOSCALE IMAGING

S. Stranick, NIST

SUMMARY

Challenges for nanoscale metrology:

- subsurface imaging and characterization- minimally invasive (perturbative)- chemically specific (spectroscopy)- DISCUSS IN TERMS OF GRAND CHALLENGE APPLICATIONS

New Instrumentation Catalyzes New Discoveries

What we develop within NNI might become important after NNI !

Thanks: NSF, DOE, DARPA, AFOSR

NANOSCALE INSTRUMENTATION & METROLOGY

NNI GRAND CHALLENGE #4 :

Challenge #4:Instrument development requires time (> 3 years grant)

Scanning Electron microscopy 1935 .. 1965 to get 10nm resolution !

Optical microscopy 1650 .. 1994 to image a single molecule !

NEIL’S EXPERIMENT

NANOSCALE INSTRUMENTATION & METROLOGY

NNI GRAND CHALLENGE #4 :

Statement #5:Funding for combined “development + application” projects

NANOPHOTONIC STRUCTURES IN NATURE

Magnetotactic Bacteria Lepidopteran Eye

Opal

Parides Sesostris

Photosynthetic Membranes

Morpho Rhetonor

ARTIFICIAL NANOPHOTONIC STRUCTURES

Particle PlasmonsNanocomposite Materials Plasmon-Biosensors

Laser Cavities

MicroresonatorsPhotonic Crystals

Light ConfinementSemiconductor Nanostructures Surface Plasmon Waveguides

Quantum Confinement

Quantum Dots

Univ. of Rochester, Boston Univ., Penn State, NIST, Rice Univ., Univ. of Illinois U-C

NEW INSTRUMENTATION FOR NANOSCALESUBSURFACE SPECTROSCOPY AND TOMOGRAPHY

Objectives: Develop measurement platform for

nanoscale subsurface spectroscopy and tomography.

Combine different spectroscopic techniques (microwave, Raman, fluorescence, IR).

Approaches:• Explore new ideas based on:

- near-field optical microscopy (field enhancement)

- microwave STM (single spin detection)

- solid immersion lens microscopy (depth resolution)

- near-field tomography (3D reconstruction)

- fluorescence self-interference (nanoscale localization)

Achievements: Raman imaging with 13 nm spatial

resolution. Localization and multi-band spectroscopy

of molecules with 0.3 nm accuracy. Microwave STM of dopants in

semiconductors, molecules, and nanostructures.

Near-field inversion algorithms for nanoscale tomography.

OBJECTIVE OF PROGRAM

Develop techniques for non-destructive, chemically specific, three-dimensional nanoscale characterization of subsurface structures.

Objective:chemicalanalysis

localization oftagged molecules

long-rangesubsurface imaging

3D objectreconstruction

Nanoscale Subsurface Spectroscopy and Tomography

Approach:near-field opticalpower extinction

tomography solid immersionlens microscopy

numerical apertureincreasing lensspectral

self-interferencefluorescence

near-field Ramanscattering and IR

absorption

microwave STM and single spin

spectroscopy

Results:(1) proof of concepts

(2) fundamental understanding of physical phenomena involved(3) combination of methods and development of single measurement platform

ATOMIC STRUCTURE

Balmer, 1885Hydrogen lamp Bohr-Sommerfeld atom model …

Adaptive OpticsSingle Molecule Detection Near-field Optics

photoreceptors in retina

Optical Tweezers

enzymatic dynamics function of motor proteins photosynthetic membranes