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Nearly isotropic piezoresistive response due to charge detour conduction in nanoparticle thin films.

ABSTRACT: Piezoresistive responses of nanoparticle thin-film strain sensors on flexible polyimide substrates were studied. Disordered interparticle tunneling introduces microscopic detour of charge conduction so as to reduce gauge factors. The disorder also results in large resistance change when current flows in the direction perpendicular to a unidirectional strain, reducing response anisotropy. For practical usages, stability and endurance of these strain sensors are confirmed with 7 × 10(4) bending cycles. Cracks form in devices under prolonged cyclic bending and slightly reduce gauge factor.

SUBMITTER: Jiang CW

PROVIDER: S-EPMC4502517 | biostudies-literature | 2015 Jul

REPOSITORIES: biostudies-literature

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Nearly isotropic piezoresistive response due to charge detour conduction in nanoparticle thin films.

Jiang Cheng-Wei CW Ni I-Chih IC Tzeng Shien-Der SD Kuo Watson W

Scientific reports 20150715

Piezoresistive responses of nanoparticle thin-film strain sensors on flexible polyimide substrates were studied. Disordered interparticle tunneling introduces microscopic detour of charge conduction so as to reduce gauge factors. The disorder also results in large resistance change when current flows in the direction perpendicular to a unidirectional strain, reducing response anisotropy. For practical usages, stability and endurance of these strain sensors are confirmed with 7 × 10(4) bending cy ...[more]

PMID: 26173736

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