Optimal concentration of holes and electrons in semiconductors for energy harvesting based on love waves propagation in a PSC film/substrate

Published papers on the topic of acoustic waves in piezoelectric semiconductor (PSC) material often deal separately with the concentrations of holes and electrons. The only exception is a recent published results by (Zhu et al., 2018), which addressed the problem using two values p0=2×1024m−3 and n0=1.2×1023m−3 of p -type semiconductor. However, when considering the both parameters p0 and n0, we need to think about an accurate balance of the concentration of holes and electrons in terms of the energy harvesting issue. Actually, in certain values of p0 and n0 the different phenomena related to the piezoelectric semiconductor properties are disappear, where the PSC material behaves like a purely elastic medium. To this end, we addressed this issue by calculating dispersion curves, mechanical displacement, electric potential, concentrations of holes and electrons under several values of p0 and n0, which has not been addressed in previous works. In comparison to the work of (Zhu et al., 2018), we shift attention from SH modes to the characteristics of Love waves in PSC-ZnO/Diamond. From a technological point of view, surface Love waves can be more convenient than SH modes in nanogenerator applications because they propagate along the surface of the half-space, which allows for significant interaction between the wave and the substrate. From a numerical point of view, we gain the freedom to extend the simplified version of the ordinary differential equation (ODE) method used by (Ben Salah et al., 2022) to consider the PSC-ZnO/Diamond heterostructure. We demonstrate how effective the p 0 and n 0 values are on the improvement of the distributions of electric potential in accordance with “Screening effect". The key observation here is that the Screening effect can provide an overview of energy harvesting. Strictly speaking, the x 1 -region from 1.57 μm to 2.35 μm for p -type semiconductor denotes the desired zone, where the electric potential of the PSC structure is positive and the concentration of holes is higher than normal level. However, the negative electrons are clearly associated with this critical x 1 -region. This observation can be highlighted by a comparison of the distributions and magnitudes of the electric potentials between the piezoelectric and PSC cases. On the other hand, it was found that the values of p0 and n0 can also affect the cut-off frequency of Love waves. However, we discuss the optimal values of p0 and n0 for minimizing the attenuation coefficient.