290
S. Papazoglou and I. Zergioti
Fig. 9.8 Optical microscopy images of SAW devices coated by overlapping droplets printed through
LIFT with a laser fluence of 650 mJ/cm 2 . Reprinted with permission from [86]. Copyright 2014,
with kind permission from Elsevier
of chemical sensors and biosensors, where laser printing may be used to deposit both
the sensing elements and the conductive electrodes of the sensor device. Among the
signal transduction mechanisms one may find resistive, capacitive, surface-acoustic
wave (SAW), film bulk acoustic resonators (FBARs) and amperometric sensors that
exhibit high sensitivity and selectivity towards the analytes under detection. In addition, the high spatial resolution of the technique enables for the dense and precise
deposition of array patterns for simultaneous multi-analyte measurements (Fig. 9.8).
More specifically, regarding chemical sensors, Tsouti et al. [77] have demonstrated the development of a capacitive chemical sensor array, able to host up to
256 sensing sites using LIFT. Various polymers have been laser transferred in this
work namely poly(2-hydroxyethyl methacrylate) (PHEMA), polyacrylic acid (PAA),
poly(4-vinylpyridine) (P4VP), poly(vinylpyrrolidone) (PVP), poly(vinyl chlorideco-vinyl acetate) (PVC-co-PVA), poly(hydroxyl styrene) (PHS) and poly(methyl
methacrylate) (PMMA) on thin silicon/LTO membrane substrates. The sensor arrays
have been tested upon exposure to different analytes such as methanol, water, and
ethanol vapors and exhibited good sensitivity depending on the analyte under investigation. In another work by Dinca et al. [17], polyethylenimine (PEI) and polyisobutylene (PIB) sensitive polymers have been laser printed on SAW substrates
for the fabrication of chemical sensors. In this case, solid-phase DRL-LIFT has
been used and it was shown that in order to avoid damage to the interdigital transducers a laser fluence under 625 mJ/cm
2 should be applied. In addition, the sensor
devices were tested upon exposure to acetone and it was highlighted that LIFT
may be used for the transfer of sensitive polymers for the fabrication of chemical sensors. Furthermore, oxides (SnO 2 ) have been transferred using LIFT and
employed different precursor systems based on UV absorbing metal complex precursors namely, SnCl 2 (acac) 2 for the preparation of the donor substrate. The devices
showed good response and the deposited polymers showed changes in their electrical
S. Papazoglou and I. Zergioti
Fig. 9.8 Optical microscopy images of SAW devices coated by overlapping droplets printed through
LIFT with a laser fluence of 650 mJ/cm 2 . Reprinted with permission from [86]. Copyright 2014,
with kind permission from Elsevier
of chemical sensors and biosensors, where laser printing may be used to deposit both
the sensing elements and the conductive electrodes of the sensor device. Among the
signal transduction mechanisms one may find resistive, capacitive, surface-acoustic
wave (SAW), film bulk acoustic resonators (FBARs) and amperometric sensors that
exhibit high sensitivity and selectivity towards the analytes under detection. In addition, the high spatial resolution of the technique enables for the dense and precise
deposition of array patterns for simultaneous multi-analyte measurements (Fig. 9.8).
More specifically, regarding chemical sensors, Tsouti et al. [77] have demonstrated the development of a capacitive chemical sensor array, able to host up to
256 sensing sites using LIFT. Various polymers have been laser transferred in this
work namely poly(2-hydroxyethyl methacrylate) (PHEMA), polyacrylic acid (PAA),
poly(4-vinylpyridine) (P4VP), poly(vinylpyrrolidone) (PVP), poly(vinyl chlorideco-vinyl acetate) (PVC-co-PVA), poly(hydroxyl styrene) (PHS) and poly(methyl
methacrylate) (PMMA) on thin silicon/LTO membrane substrates. The sensor arrays
have been tested upon exposure to different analytes such as methanol, water, and
ethanol vapors and exhibited good sensitivity depending on the analyte under investigation. In another work by Dinca et al. [17], polyethylenimine (PEI) and polyisobutylene (PIB) sensitive polymers have been laser printed on SAW substrates
for the fabrication of chemical sensors. In this case, solid-phase DRL-LIFT has
been used and it was shown that in order to avoid damage to the interdigital transducers a laser fluence under 625 mJ/cm
2 should be applied. In addition, the sensor
devices were tested upon exposure to acetone and it was highlighted that LIFT
may be used for the transfer of sensitive polymers for the fabrication of chemical sensors. Furthermore, oxides (SnO 2 ) have been transferred using LIFT and
employed different precursor systems based on UV absorbing metal complex precursors namely, SnCl 2 (acac) 2 for the preparation of the donor substrate. The devices
showed good response and the deposited polymers showed changes in their electrical