Core-Level Shift of Graphene with Number of Layers Studied by Microphotoelectron Spectroscopy and Electrostatic Force Microscopy

Recently, there have been a number of variations of electrostatic force microscopy (EFM) that allow for the measurement of time-varying forces arising from phenomena such as ion transport in battery materials or charge separation in photovoltaic systems. These forces reveal information about dynamic processes happening over nanometer length scales due to the nanometer-sized probe tips used in atomic force microscopy. Here, we review in detail several time-resolved EFM techniques based on non-contact atomic force microscopy, elaborating on their specific limitations and challenges. We also introduce a new experimental technique that can resolve time-varying signals well below the oscillation period of the cantilever and compare and contrast it with those previously established.

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Vector voltage measurement of MMICs using Electrostatic Force Microscopy

Symposium on Antenna Technology and Applied Electromagnetics [ANTEM 2000] ◽

10.1109/antem.2000.7851671 ◽

2000 ◽

Author(s):

C.J. Falkingham ◽

G.E. Bridges ◽

I.R.H Edwards

Keyword(s):

Electrostatic Force ◽

Electrostatic Force Microscopy ◽

Voltage Measurement ◽

Force Microscopy

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Broadband nanodielectric spectroscopy by means of amplitude modulation electrostatic force microscopy (AM-EFM)

Ultramicroscopy ◽

10.1016/j.ultramic.2011.05.001 ◽

2011 ◽

Vol 111 (8) ◽

pp. 1366-1369 ◽

Cited By ~ 23

Author(s):

G.A. Schwartz ◽

C. Riedel ◽

R. Arinero ◽

Ph. Tordjeman ◽

A. Alegría ◽

...

Keyword(s):

Amplitude Modulation ◽

Electrostatic Force ◽

Electrostatic Force Microscopy ◽

Force Microscopy

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Surface-core-level shift and valence-band studies of the Dy c(2×2) structure on W(100)

Surface Science ◽

10.1016/j.susc.2004.07.044 ◽

2004 ◽

Vol 569 (1-3) ◽

pp. 118-124

Author(s):

N. Moslemzadeh ◽

S.D. Barrett ◽

V.R. Dhanak ◽

G. Miller

Keyword(s):

Valence Band ◽

Core Level ◽

Level Shift ◽

Core Level Shift

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Ab-initio calculations of the initial- and final-state effects on the surface core-level shift of transition metals

Surface Science Letters ◽

10.1016/0167-2584(93)90536-r ◽

1993 ◽

Vol 287-288 ◽

pp. A418

Author(s):

M. Methfessel ◽

D. Hennig ◽

M. Scheffler

Keyword(s):

Transition Metals ◽

Ab Initio Calculations ◽

Ab Initio ◽

Core Level ◽

Level Shift ◽

Final State ◽

Core Level Shift

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Microstructure and Local Charge Distribution in Hydrogenated Nanocrystalline Silicon under Illumination Studied by Electrostatic Force Microscopy.

MRS Proceedings ◽

10.1557/opl.2013.32 ◽

2013 ◽

Vol 1493 ◽

pp. 201-206

Author(s):

Rubana Bahar Priti ◽

Venkat Bommisetty

Keyword(s):

Grain Boundaries ◽

Charge Distribution ◽

Bias Voltage ◽

Electrostatic Force ◽

Nanocrystalline Silicon ◽

Electrostatic Force Microscopy ◽

Strained Si ◽

Force Microscopy ◽

Local Charge ◽

Before And After

ABSTRACTHydrogenated nanocrystalline silicon (nc-Si:H) is a promising absorber material for photovoltaic applications. Nanoscale electrical conductivity and overall electronic quality of this material are significantly affected by film microstructure, specifically the density and dimension of grains and grain-boundaries (GB). Local charge distribution at grains and grain/GB interfaces of nc-Si:H was studied by Electrostatic Force Microscopy (EFM) in constant force mode under illumination of white LED. Bias voltage from -3V to +3V was applied on the tip. Scanning Kelvin Force (KFM) images were taken before and after illumination to study the change in surface photovoltage (SP). EFM and KFM analysis were combined with film topography to draw a correlation between surface morphology and nanoscale charge distribution in this material. After illumination, small blister like structures were observed whose size and density increase with time. Raman spectroscopy confirmed these new structures as nanocrystalline silicon. This change was assumed due to relaxation of strained Si-Si bonds as an effect of photo response. Nanocrystalline grain interiors were at lower potential and amorphous grain boundaries were at higher potential for negative bias; it was opposite for positive bias. Change in polarity in bias voltage reversed the polarity of the potential in grains and GBs indicating the dominance of negative type of defects. Further study with current sensing AFM in dark and illumination with variable bias voltages will be able to identify the type and density of defects in grains and grain/GB interfaces.

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