Epoxy based photoresist/carbon nanoparticle composites

Lillemose, Michael; Gammelgaard, Lene; Richter, Jacob; Thomsen, Erik Vilain; Boisen, Anja

doi:10.1016/j.compscitech.2008.01.017

Cited by 19 publications

(9 citation statements)

References 16 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…While this will yield a value of < G > which depends on ε , it does not affect the following qualitative discussion. A clear cut and very sharp peak in < G > is observed with a maximum value (4330) well above that of reported values in other composite materials . In other samples, values of up to ≈12 000 have been observed.…”

Section: Piezoresistive Behavior As a Function Of φsupporting

confidence: 71%

“…Strains of several percent under hydrostatic pressure or uniaxial stress have also been observed to significantly modify the electrical resistance of composites. Consequently composite materials near the percolation threshold are now widely recognized as being of potential interest as sensitive strain gages because they may exhibit a so‐called giant piezoresistance . Piezoresistance is defined as the resistance change induced by an applied mechanical stress, and its magnitude is quantified by the gage factor, G , defined as the relative resistance change per unit strain ( ε ):

\begin{matrix} true \\ right G = \frac{Δ R}{R_{0}} \frac{1}{ɛ} = \frac{1}{R_{0}} \frac{normald R}{normald ɛ} \end{matrix}

where R is the resistance under applied stress and R 0 is the reference (or zero‐stress) resistance.…”

Section: Introductionmentioning

confidence: 99%

“…The literature on conducting composites deals generally with physical mixtures of insulating particles and particles of either a carbon allotropes or metallic particles . Once mixed, the relative volumes of the two components determine a value for φ which cannot be subsequently modified.…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Piezoresistive Properties of Ag/Silica Nano‐Composite Thin Films Close to the Percolation Threshold

Gupta

Gacoin

Rowe

2014

Adv Funct Materials

View full text Add to dashboard Cite

The effect of mechanical stress on the electrical properties of Ag/silica nano‐composite sol–gel films, fabricated using an ultra‐violet (UV) photo‐reduction process, is studied over a large range of Ag volume fractions, φ. The ability to finely tune φ in situ by varying the UV exposure time enables the direct identification of the critical volume fraction, φ* ≈ 13.1%, around which the resistance changes by 6 orders of magnitude and the average piezoresistive gage factor, , peaks at 4330. is orders of magnitude larger than that of bulk silicon and φ* is close to the value expected for percolation in 3 dimensions. It is shown experimentally that this giant piezoresistance is the result of a stress‐induced change in the average Ag cluster size that significantly modifies the sample resistance when φ ∼ φ*. In terms of the potential use of any composite material as a sensitive strain sensor, a sensor figure‐of‐merit (F) that accounts for both and for the measured, expected divergence in resistance fluctuations close to φ* is defined. It is shown that maximum F is achieved in composites slightly to the metallic side of the percolation transition. In the case studied here, the maximum value of F, which is 5–10 times larger than that measured on commercial strain gages under the same conditions, is obtained for φ ≈ 13.4%. The ability to finely tune φ in‐situ therefore suggests that Ag/silica nano‐composites could be the basis for a highly sensitive, low power, strain sensing technology.

show abstract

Section: Piezoresistive Behavior As a Function Of φsupporting

confidence: 71%

\begin{matrix} true \\ right G = \frac{Δ R}{R_{0}} \frac{1}{ɛ} = \frac{1}{R_{0}} \frac{normald R}{normald ɛ} \end{matrix}

where R is the resistance under applied stress and R 0 is the reference (or zero‐stress) resistance.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Piezoresistive Properties of Ag/Silica Nano‐Composite Thin Films Close to the Percolation Threshold

Gupta

Gacoin

Rowe

2014

Adv Funct Materials

View full text Add to dashboard Cite

show abstract

“…Most of these applications require good mechanical properties. SU8 is a suitable candidate due to its high E Y value 9 compared to other polymers, but has the disadvantage of being brittle with high internal stress 5. Therefore, we are aiming to prepare composites to improve mechanical properties of SU8.…”

Section: Introductionmentioning

confidence: 99%

Study of the mechanical response of carbon nanotubes‐SU8 composites by nanoindentation

Mionić¹,

Jiguet²,

Judelewicz³

et al. 2010

Physica Status Solidi (b)

View full text Add to dashboard Cite

Multiwalled carbon nanotubes (MWCNTs)/SU8 composites have been produced to enhance the mechanical properties of SU8 photoresist. We have studied the influence of SU8 solvent on the structural homogeneity of composites through nanoindentation testing. It is found that acetone and propylene glycol methyl ether acetate (PGMEA) are very suitable solvents to prepare MWCNTs/SU8 composites with significant increase of the Young's modulus (E Y ). The highest increase of E Y in respect to the parent material of 104% was obtained with acetone as solvent. It was noticed that the remaining solvent in the composite influences strongly E Y , as well.

show abstract

“…6 Electrically conductive polymer composites have been demonstrated as inexpensive and efficient materials sensitive to pressure variation, deformation, and temperature. 7,8 These materials can be made by dispersing high concentrations of electrically conductive particles, for instance, carbon black (CB) particles [9][10][11][12][13][14][15] or metal particles, [16][17][18] in dielectric polymer matrices. The dispersed particles will form electrically conductive pathways in the polymer matrix if the particle concentration is sufficiently high, above the percolation threshold.…”

Section: Introductionmentioning

confidence: 99%

Microelectromechanical strain and pressure sensors based on electric field aligned carbon cone and carbon black particles in a silicone elastomer matrix

Høyer

Knaapila

Kjelstrup‐Hansen

et al. 2012

Journal of Applied Physics

View full text Add to dashboard Cite

Methods for developing microelectromechanical strain and pressure sensors based on aligned carbon particle strings within dielectric elastomer matrices are presented. Two different types of carbon particles were used: a mixture of carbon cone and carbon disk particles and spherical carbon black particles. The particles were assembled and aligned into strings by an alternating electric field with a strength of 4 kV/cm and a frequency of 1 kHz, utilizing the dielectrophoretic effect. The particle fraction was about 0.1 vol. %, which is an order of magnitude lower than their percolation threshold (∼2 vol. %). The aligned strings were produced in a couple of minutes. The matrices were subsequently cured thus stabilizing the strings. Micromechanical strain sensors with a capacitive readout were produced by aligning the particles into a single string-like formation in the in-plane direction, the string dimensions being 3 μm width and 30 μm length. The pressure sensors with piezoresistive readout were made by aligning the particles into multiple unidirectional strings in the out-of-plane direction, the thickness of the sensors being of the order of 100 μm and the lateral area of 1.5 cm2. The strain and the pressure sensors show reversible piezocapacitive and piezoresistance effects when stretched and compressed, respectively.

show abstract

Epoxy based photoresist/carbon nanoparticle composites

Cited by 19 publications

References 16 publications

Piezoresistive Properties of Ag/Silica Nano‐Composite Thin Films Close to the Percolation Threshold

Piezoresistive Properties of Ag/Silica Nano‐Composite Thin Films Close to the Percolation Threshold

Study of the mechanical response of carbon nanotubes‐SU8 composites by nanoindentation

Microelectromechanical strain and pressure sensors based on electric field aligned carbon cone and carbon black particles in a silicone elastomer matrix

Contact Info

Product

Resources

About