10 research outputs found
Investigation of the AFM Contact-Mode Force Calibration with Simulation
Force-curves measured by Atomic Force Microscopy (AFM) are frequently used to determine the local Young’s Modulus of the sample. Originally the AFM (Atomic Force Microscopy) instruments measure the cantilever deflection as a voltage signal; however the natural unit of the deflection is nanometer. In general, the V/nm conversion factor is determined from the force-curve of a hard sample. Since this conversion is highly affects the value of the Young’s modulus, the accuracy of this method was investigated experimentally and using a finite element simulation of the cantilever motion. It was found, that the position of the laser spot significantly modify the conversion factor and in case of the sample with steep surface, the error of this calibration method can be significant
Characterization of the shape of gold nanoparticles prepared by thermal annealing
Gold nanoparticles – which are intended to be used as transducers in a localized surface plasmon resonance (LSPR) sensor – were prepared by thermally annealing various layers of gold thin films deposited on glass substrate. The size and distribution of nanoparticles were investigated by atomic force microscopy (AFM). The changes in the nanoparticle shape in function of the deposition and annealing parameters are characterized. A novel parameter called localization factor was used to investigate the shape of the resulting particles. A common problem concerning the AFM imaging of nanoparticles, namely the tip convolution effect was studied, and possibilities to use the localization factor parameter to optimize surface reconstruction algorithms via tip deconvolution is demonstrated
Investigation of the Local Mechanical Properties of the SAC Solder Joint with AFM
Considering
the size o
f the natural appearance of the
micro alloy
components
of a SAC
solder joint,
AFM was used to investigate their mechanical properties
in the form of their natural
appearance
.
C
ontact
-
mode point
-
spectroscopy
was
done to determine
the
elastic modulus and
tapping
-
mode point
-
spectroscopy
was
done to investigate
the
tip
-
sample power dissipation.
The measured Young’s modulus values of the Cu
, IML, Ag
3
Sn and Sn
components
, were 125±9
GPa, 111±20 GPa, 67±11 GPa and 57±16 GPa, respectively.
The
dissipation measurements were
accomplished by Si and diamond probe
s
with different spring con
stants. T
he
different
characteristics of the results are
dis
cussed
Investigation of the Performance of Thermally Generated Au/Ag Nanoislands for SERS and LSPR Applications
In this work the performance of Au/Ag nanoislands was investigated for Surface Enhanced Raman Spectroscopy (SERS) and Localized Surface Plasmon Resonance (LSPR) applications. The nanoislands were generated by thermally annealing thin layers of silver and gold (having thickness in the 5-15 nm range), which were previously sputtered onto glass surfaces. Both pure (silver and gold nanoparticles – AuNP and AgNP) and composite metallic systems (silver-gold core-shell structures – Ag-Au core-shell) were evaluated based on their plasmonic and SERS sensitivity. Atomic Force Microscopy (AFM) and Scanning Electron Microscopy (SEM) were used to measure the size, shape and distribution of the nanoparticles to correlate them with the obtained plasmonic/Raman capabilities. The technological parameters of nanoisland fabrication for optimal sensitivities are presented
A Review on Current eCall Systems for Autonomous Car Accident Detection
The aim of the paper is to give an overview on the existing eCall solutions for autonomous car accident detection. The requirements and expectations for such systems, considering both technological possibilities, legal regulatory criteria and market demands are discussed. Sensors utilized in e-call systems (crash sensing, systems for positional and velocity data, and communication solutions) are overviewed in the paper. Furthermore, the existing solutions for eCall devices are compared based on their level of autonomy, technical implementation and provided services
Investigation of the performance of thermally generated gold nanoislands for LSPR and SERS applications
In this work, the performance of gold nanoislands was investigated for Localized Surface Plasmon Resonance (LSPR) and Surface Enhanced Raman Spectroscopy (SERS) applications. Nanoislands were generated by thermally annealing thin layers of gold (having thickness in the 6-12 nm range), which was previously deposited by vacuum thermal evaporation onto glass substrates. Gold nanoparticles (AuNP) were evaluated based on their plasmonic and SERS performance and morphological properties. Scanning Electron Microscopy (SEM) was used to measure the average particle size and average interparticle distance in order to correlate them with the obtained plasmonic/Raman capabilities. The technological parameters of nanoisland fabrication for optimal performances were also determined
Robust transmission of MPEG-4 video: start codes substitution and length field insertion assisted unequal error protection
Consiglio Nazionale delle Ricerche - Biblioteca Centrale - P.le Aldo Moro, 7 , Rome / CNR - Consiglio Nazionale delle RichercheSIGLEITItal