Theoretical Analysis and Characteristic Study of Li-Doped P-Type ZnO Ultra-Thin Cantilever Beam Accelerometer

TL;DR

This paper studies how adding lithium to ZnO ultra-thin cantilever beams improves their piezoelectric properties and sensitivity for accelerometers.

Contribution

The novel contribution is the theoretical analysis of Li-doped ZnO's electronic and piezoelectric properties and its application in ultra-thin cantilever beam accelerometers.

Findings

Li doping increases ZnO's bandgap from 0.74 to 1.21 eV as doping ratio rises to 10%.

The piezoelectric coefficient of Li-doped ZnO increases from 2.07 to 3.3 C/m² with higher doping.

An ultra-thin Li-doped ZnO cantilever beam accelerometer achieves a sensitivity of 7.04 mV/g.

Abstract

Nonlinear correction was performed on the mechanical motion of ultra-thin cantilever beams, and strain effects were calculated on ultra-thin multi-layer heterogeneous material stacked cantilever beams. The atomic structure and piezoelectric properties of ZnO were studied using first-principles calculations. In this study, generalized gradient approximations of Perdew–Burke–Erzerhof (GGA-PBE) functionals and Plain Wave Basis Sets were used to calculate the electronic structure, density of states, energy bands, charge density, and piezoelectric coefficient of intrinsic ZnO. Research and calculations were conducted on Li-doped ZnO with different ratios. According to our calculations, as the Li doping ratio increases from 0 to 10%, the bandgap width of ZnO material increases from 0.74 to 1.21 eV. The results for the density of states and partial density of states indicate that the increase in band gap is due to the movement of Zn-3d states towards the high-energy end, and the piezoelectric coefficient of the material increases from 2.07 to 3.3 C/m2. Meanwhile, based on the optimized Li-doped ZnO cantilever beam accelerometer, an ultra-thin cantilever beam accelerometer with a sensitivity of 7.04 mV/g was fabricated.

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