Piezoelectric effect in GaAs nanowires: experiment and theory

Abstract

The anomalous piezoelectric effect in GaAs nanowires was detected (the piezoelectric strain coefficient up to d33 ≈ 26 pC/N) that is 12 times larger than the theoretically estimated value. This result is explained by the dominant content of the phase with the wurtzite‐type crystal structure in GaAs nanowires and an increased pressing force by the contact layer on the nanowire. (© 2016 WILEY‐VCH Verlag GmbH &Co. KGaA, Weinheim)

Piezoelectric effect in wurtzite GaAs nanowires: Growth, characterization, and electromechanical 3D modeling

“…Evaluated PSC values distributed from 0 to 26 pC/N and have a maximal value in structure with density of 10 9 cm −2 , which differs significantly from table values d 33 = 0 and d 14 = 2.7 pC/N . This difference was also explained by two factors : (i) the used material in the form of NW contains mostly a wurtzite phase; (ii) the pressing force enhancement (PFE) through the contact metal layer to the NW.…”

“…It is known that a change in the crystal structure for II–VI compounds can cause a significant change in device piezoelectric properties . The earliest studies of the piezoelectric properties of GaAs NWs covered by polymethyl methacrylate (PMMA) were presented experimentally and theoretically ; however, more detailed consideration of potential distribution in such structures is still required. Evaluated PSC values distributed from 0 to 26 pC/N and have a maximal value in structure with density of 10 9 cm −2 , which differs significantly from table values d 33 = 0 and d 14 = 2.7 pC/N .…”

“…The earliest studies of the piezoelectric properties of GaAs NWs covered by polymethyl methacrylate (PMMA) were presented experimentally and theoretically ; however, more detailed consideration of potential distribution in such structures is still required. Evaluated PSC values distributed from 0 to 26 pC/N and have a maximal value in structure with density of 10 9 cm −2 , which differs significantly from table values d 33 = 0 and d 14 = 2.7 pC/N . This difference was also explained by two factors : (i) the used material in the form of NW contains mostly a wurtzite phase; (ii) the pressing force enhancement (PFE) through the contact metal layer to the NW.…”

“…In this paper, we develop the mechanical 3D model by adding an electrostatic module to explain the potential distribution in the periodic NW structure with and without a PMMA coating and compare with experimental data.…”

Highly sensitive piezotronic pressure sensors based on undoped GaAs nanowire ensembles

“…In Ref. [26], the authors have shown that electrically contacting NW ensembles may result in a significant increase in effective strain in the NWs, leading to an enhancement of the apparent piezoelectric coefficients by up to 2 orders of magnitude. It is very likely that this effect significantly affects the response of our pressure-sensitive piezotronic device.…”