Analysis On The Coupling Of Electric-Mechanical-Charge Carrier In A Few Typical Piezoelectric Semiconductor Structures

Piezoelectric semiconductor materials have a very wide range of applications because of the piezoelectric and semiconducting properties, especially in the field of microelectronic devices and optoelectronic devices. Therefore, it is of great significance to carry out the research of the mechanical behavior of the new intelligent material structure.In this paper, three kinds of piezoelectric semiconductor structures are studied, and the coupling effects of electric-mechanical-charge carriers in these three kinds of structures are analyzed. Firstly, the anti-plane deformation of a piezoelectric semiconductor plate with circular hole is solved, and the distribution of the stress, charge carrier concentration, electric field, shear strain and electric displacement in the vicinity of the circular hole are calculated. It is found that the distribution of the shear stress and the current intensity near the circular hole is independent of the characteristics of the semiconductor. And the distribution of the electric field strength, shear strain, charge carrier concentration and electric potential are affected by the doping concentration of the semiconductor. The greater the doping concentration, the faster the electric field intensity and the electric displacement move around the hole, the smaller the concentration degree of the carrier in the hole boundary. Aiming at the problem of piezoelectric p-n junctions with axial force, we consider the internal electric field effect of p-n junctions, the relevant analysis model is established. The distribution of electric field and the distribution of carriers in p-n junction are obtained. The local current in the p-n junction is calculated by the change of minority carrier. Finally, we study the transverse bending problem of the rectangular cross section Zinc Oxide nanowires. According to the basic equation of the piezoelectric semiconductor structure, the expressions of the physical quantities such asvoltage potential, charge carrier concentration and electric field intensity are derived.Then the distribution law of each physical quantity is analyzed by numerical calculation.We find that the stretching side of the nanowire is presented as a positive potential, and the pressure side is negative. The effect of doping concentration on the results is analyzed,increasing the doping concentration of the material will reduce the potential of the nanowire. Because mechanical electric coupling performance of the material is weak, the position of the neutral layer of the section is almost not affected.Through the research of this paper, we have a further understanding of the characteristics of the piezoelectric semiconductor materials, and the results obtained have important guiding significance for the research and development of piezoelectric semiconductor structures and devices.