SH waves in a stressed piezoelectric semiconductor plates: Electron and hole drift phenomenon

Abstract

• Simplified version of ODE method for a stressed piezoelectric semiconductor plate • The influence of biaxial stresses on the drift of electrons and holes phenomenon • For σ 11 0 =2.7 GPa, phase velocity in piezoelectric plate is exactly similar to that found in stressed PSC plate Can the residual stresses affect significantly the drift of electrons and holes? The main goal of this research is to provide answers to this question. Although the behavior of acoustic wave in stressed purely piezoelectric plates is a thoroughly studied subject, very few works account for piezoelectric semiconductor (so-called piezotronics) structures because of the complexity related to the large size of the square matrix to be solved. To study the characteristics of stressed piezotronics material, this paper presents a numerical matrix solution to predict the dispersion curves of shear horizontal (SH) modes. Detailed formulations of waves are given to highlight the differences from the piezoelectric and piezotronics materials. Some interesting observations are observed from the numerical and physical points of views. Numerically, existing efforts mainly focused on finding a balance between the large sizes of the square matrix, accuracy solution and the time spend for obtained the solution. Accordingly, a simplified version of ordinary differential equation (ODE) method is proposed. This version presents one of the significant improvement of the present work. Physically, drift of electrons and holes phenomenon is present for the pre-stressed piezotronics medium that undoubtedly can disruption the ideal vibration of acoustic wave (decrease the kinetic of waves). Thereby, a comparison of the dispersion curves of SH modes in pre-stressed piezoelectric and piezotronics plates answers this need and sets forth to explore the effects of semi-conductive properties. Overall, frequency spectrum of fundamental mode can reach about 2.8 × 10 9 rad/s and 2.7 × 10 9 rad/s for piezoelectric and piezotronics, respectively. In addition, this article highlights the challenges faced in the acoustoelastic effect on drift of electrons and holes and provides a discussion of the influence of biaxial stresses. Therefore, this critical point could provide the deep understanding of the stressed semiconductor structures. Besides answering a basic question about the numerical and physical problems of piezotronics thin structures, our results find applications especially in areas of smart devices with small sizes.