01 e 03 de novembro
2º Semestre de 2016
Instituto de Física
Universidade de São Paulo
Professores:
Antonio Domingues dos Santos
Manfredo H. Tabacniks
Energia /
Momento
Matéria
Propriedade
a ser
caracterizada
Fótons
Íons
Átomos
Elétrons
Neutrons
Prótons
Fótons
Íons
Átomos
Elétrons
Neutrons
Prótons
Energia /
Momento
Matéria
•Microscopias de Sonda Local
(SPM)
Nature Nanotechnology, 1 (2006) 3
Energia /
Momento
Matéria
Propriedade
a ser
caracterizada
Interação
matéria-matéria,
(ou
radiação-matéria)
Detectam-se forças
ou corrente
elétrica (ou
intensidade
luminosa)
Energia /
Momento
Matéria
•Microscopias de Sonda Local
(SPM)
Nature Nanotechnology, 1 (2006) 3
Interação Ponta-Amostra
Microscópio de tunelamento
eletrônico (STM)
Um pouco de história
Heinrich Rohrer and Gerd K. Binnig, scientists at IBM's Zurich Research
Laboratory in Switzerland, are awarded the 1986 Nobel Prize in physics for their work in scanning tunneling microscopy. Binnig and Rohrer were recognized for developing the powerful Scanning Tunneling Microscopy technique. They shared the award with German scientist Ernst Ruska, designer of the first Electron Microscope.
US Pat. 4343993.
IBM. J. Res. Dev. v.30, N4, 355 (1986)
Experimental setup of first AFM from paper Binnig, Quate and
Gerber
(Phys.Rev.Lett.56,930 (1986))
.
Despite of the great success of the Scanning Tunneling Microscopy it was obvious that STM has fundamental disadvantage - with STM one can investigate only the conductive or conductive layers coated samples.
This disadvantage was overcomed due to the invention of atomic force microscope by Binnig (US Pat. 4724318). He was first who have guessed that under interaction with sample surface macroscopic cantilever provided with sharp tip can be bended by atomic forces to sufficiently large amount to be measured by the common facilities. In first
embodiment to measure tip displacement was used STM
Um pouco de história
Russell Young and his co-workers Fredric Scire and John Ward (left to right) with the Topografiner. It must be noted however that as long as in 1966 Russell Young has stated idea about an opportunity to acquire the surface topography with usage of current between surface and sharp metallic tip. In 1971 he have published paper about device called Topographiner, which contained all major assemblies of Scanning Probe Microscope.
Phys. Rev. Lett. V. 27, N 14, 1971, P. 922-924 Rev. Sc. Instr. V. 43, N 7, 1972, P. 999-1011
Phys. Rev. Lett. 27, 922–924 (1971)
Observation of Metal-Vacuum-Metal Tunneling, Field Emission, and the Transition Region
Russell Young
,
John Ward
, and
Fred Scire
National Bureau of Standards, Washington, D. C. 20234
Received 26 August 1971; published in the issue dated 4 October 1971
We report what we believe are the first observations of metal-vacuum-metal tunneling. A field emitter is
brought close to a metal surface and the current-voltage characteristic is measured in three regions: the
Fowler-Nordheim region, the intermediate region, and-and the metal-vacuum-metal region.
© 1971 The American Physical Society
URL: http://link.aps.org/doi/10.1103/PhysRevLett.27.922
DOI: 10.1103/PhysRevLett.27.922
Interação Ponta-Amostra
Microscópio de força atômica (AFM)
Fig. 2 Schematic sketch of AFM from Patent "Atomic Force
Microscope"
(US RE37,299)
.
For registration of cantilever bending many methods was used, but currently mostly useful and widely used is method invented by Amer and Meyer (see Fig. 2)
US Pat. RE37,299 (Reissued Pat. No. 5,144,833)
amostra magnética
fibra óptica
metalizada
sistema de varrredura
da amostra (XYZ)
afinada e
lock-in
piezo-stack
gerador
de sinais
diapasão
bloco metálico
laser
Fotodiodo
segmentado
Diapasão de quartzo
(tuning-fork)
Interação Ponta-Amostra
Microscópio de força
atômica (AFM)
Interação Ponta-Amostra
Microscópio de força
atômica (AFM)
•
Desenvolvemos uma nova unidade de AFM, operando no modo
“tapping”. Neste caso o diapasão foi montado na horizontal. Para os
testes iniciais, usamos pontas de tungstênio. Construímos as células
eletroquímicas para a corrosão de fios de W e preparação da pontas.
Microscópio de força atômica
Imagem de erro
Imagem de fase
Nanopartículas de
cobre
Imagem
topográfica
Imagem de fase
Interação Ponta-Amostra
Software
Functions:
- Control of the system
- Image acquisition
- Image processing
Disponibility:
- Software dedicated
- WSXM from Nanotec
- Open Source GXSM Software
(Linux)
Tip-sample distance control
- Contact mode
- Tapping mode
- Shear-force mode
Image construction
- Feedback control signal
- Direct measurement of any
specific signal
(amplitude or phase)
Piezo-electric Scanner
- Tube
- Flexure
- Bimorphes
Feedback Control
P
I
Signal
Setpoint
error
Proportional
Integral
Z-piezo
output
Modo de Operação
Microscópio de força
atômica (AFM)
-
Modo de contato
-
Modo “tapping”
(intermitente)
““ver simuladores””
Modo de Operação
Microscópio de força
atômica (AFM)
-
Força normal
-
Força lateral
Modo de Operação
Microscópio de força
atômica (AFM)
-
Força normal
Nature Nanotechnology, 6 (2011) 191
Comparação entre técnicas
Microscópio
ótico
AFM
MEV
DME - Danish Micro Engineering A/S
Herlev, Denmark
PSIA Corp.
Sungnam, Korea
JPK Instruments AG
Berlin, Germany
QuantomiX
Nes-Ziona, Israel
NT-MDT, Molecular Devices and Tools for Nanotechnology,
Moscow, Russia
Quesant Instruments
,
Agoura Hills, CA
Molecular Imaging Corporation,
Phoenix, AZ.
RHK Technology, Inc.
,
Rochester Hills, MI
Nanosurf AG
,
Liestal, Switzerland
Surface Imaging Systems GmbH
,
Herzogenrath, Germany
Nanotec Electronica
Madrid, Spain
Triple-O Microscopy GmbH,
Potsdam, Germany
Novascan Technologies, Inc.
Ames, IA
Veeco Metrology Group
Woodbury, NY
Omicron Vacuumphysik GmbH,
Taunusstein, Germany
Veeco Metrology Group was formed through the merger of Digital Instruments, Santa Barbara, CA and TM Microscopes, formerly ThermoMicroscopes, Inc., Sunnyvale, CA Merged brands also include Topometrix and Park Scientific Instruments.
