TY - JOUR
T1 - Transparent, Flexible, Conformal Capacitive Pressure Sensors with Nanoparticles
AU - Kim, Hyeohn
AU - Kim, Gwangmook
AU - Kim, Taehoon
AU - Lee, Sangwoo
AU - Kang, Donyoung
AU - Hwang, Min Soo
AU - Chae, Youngcheol
AU - Kang, Shinill
AU - Lee, Hyungsuk
AU - Park, Hong Gyu
AU - Shim, Wooyoung
N1 - Funding Information:
H.K. and G.K. contributed equally to this work. This research was supported by Engineering Research Center (2015R1A5A1037668) and Mid-career Researcher Program (2017R1A2B2009751) through the National Research Foundation (NRF) of Korea. H.-G.P. acknowledges support by the NRF of Korea (2009-0081565).
PY - 2018/2/22
Y1 - 2018/2/22
N2 - The fundamental challenge in designing transparent pressure sensors is the ideal combination of high optical transparency and high pressure sensitivity. Satisfying these competing demands is commonly achieved by a compromise between the transparency and usage of a patterned dielectric surface, which increases pressure sensitivity, but decreases transparency. Herein, a design strategy for fabricating high-transparency and high-sensitivity capacitive pressure sensors is proposed, which relies on the multiple states of nanoparticle dispersity resulting in enhanced surface roughness and light transmittance. We utilize two nanoparticle dispersion states on a surface: (i) homogeneous dispersion, where each nanoparticle (≈500 nm) with a size comparable to the visible light wavelength has low light scattering; and (ii) heterogeneous dispersion, where aggregated nanoparticles form a micrometer-sized feature, increasing pressure sensitivity. This approach is experimentally verified using a nanoparticle-dispersed polymer composite, which has high pressure sensitivity (1.0 kPa–1), and demonstrates excellent transparency (>95%). We demonstrate that the integration of nanoparticle-dispersed capacitor elements into an array readily yields a real-time pressure monitoring application and a fully functional touch device capable of acting as a pressure sensor-based input device, thereby opening up new avenues to establish processing techniques that are effective on the nanoscale yet applicable to macroscopic processing.
AB - The fundamental challenge in designing transparent pressure sensors is the ideal combination of high optical transparency and high pressure sensitivity. Satisfying these competing demands is commonly achieved by a compromise between the transparency and usage of a patterned dielectric surface, which increases pressure sensitivity, but decreases transparency. Herein, a design strategy for fabricating high-transparency and high-sensitivity capacitive pressure sensors is proposed, which relies on the multiple states of nanoparticle dispersity resulting in enhanced surface roughness and light transmittance. We utilize two nanoparticle dispersion states on a surface: (i) homogeneous dispersion, where each nanoparticle (≈500 nm) with a size comparable to the visible light wavelength has low light scattering; and (ii) heterogeneous dispersion, where aggregated nanoparticles form a micrometer-sized feature, increasing pressure sensitivity. This approach is experimentally verified using a nanoparticle-dispersed polymer composite, which has high pressure sensitivity (1.0 kPa–1), and demonstrates excellent transparency (>95%). We demonstrate that the integration of nanoparticle-dispersed capacitor elements into an array readily yields a real-time pressure monitoring application and a fully functional touch device capable of acting as a pressure sensor-based input device, thereby opening up new avenues to establish processing techniques that are effective on the nanoscale yet applicable to macroscopic processing.
KW - conformal sensors
KW - flexible sensors
KW - health monitoring
KW - large-scale touch interfaces
KW - nanoparticle-roughened dielectrics
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U2 - 10.1002/smll.201703432
DO - 10.1002/smll.201703432
M3 - Article
C2 - 29372583
AN - SCOPUS:85041077598
VL - 14
JO - Small
JF - Small
SN - 1613-6810
IS - 8
M1 - 1703432
ER -