SU-8-based nanocomposites for acoustical matching layer.
SU-8, an epoxy-based photoresist, was introduced as the acoustical matching layer between silicon and water for lab-on-chip applications integrating acoustic characterization. Acoustical performances, including the acoustic longitudinal wave velocity and attenuation of the SU-8-based matching layer, were characterized at a frequency of 1 GHz at room temperature. The gain in echo characterization with a SU-8/SiO2 bilayer and with different nanocomposite monolayers made of SU-8 and TiO2 nanoparticles (size around 35 nm) between silicon and water was characterized as being above 10 dB in each case. With the increase of concentration of TiO2 in SU-8 based composites from 0 to 30 wt%, acoustical impedance of the nanocomposites increased from about 3 to 6 MRayls, respectively. The acoustical attenuation in the nanocomposites is between 0.5 and 0.6 dB/microm. The most efficient matching was obtained with the nanocomposite integrating 30 wt% TiO2 nanoparticles, with which the enhanced loss is about 0.34 dB as the attenuation is about 0.5 dB/microm. This type of matching layer has potential applications in lab-on-chip technology for high frequency transducers or in the fabrication of high frequency piezocomposites.
Wang
Shengxiang
S
Campistron
Pierre
P
Carlier
Julien
J
Callens-Debavelaere
Dorothée
D
Nongaillard
Bertrand
B
NDieguene
Assane
A
Nassar
Georges
G
Soyer
Caroline
C
Zhao
Xingzhong
X
D000162:Acoustics; D000465:Algorithms; D001709:Biotechnology; D017097:Electric Impedance; D004852:Epoxy Compounds / Q000737:chemistry*; D055617:Micro-Electrical-Mechanical Systems; D008956:Models, Chemical; D053761:Nanocomposites / Q000737:chemistry*; D011108:Polymers / Q000737:chemistry*; D012822:Silicon Dioxide / Q000737:chemistry; D014025:Titanium / Q000737:chemistry; D014159:Transducers
D004852:Epoxy Compounds; D011108:Polymers; C520895:SU-8 compound; C009495:titanium dioxide; D012822:Silicon Dioxide; D014025:Titanium