An accurate computational method for analysis of electromechanical properties of structures with metal-GaN piezoelectric semiconductor contact

An accurate computational method is proposed to analyze the electromechanical characteristic of structures of metal-piezoelectric semiconductor contact based on the nonlinear theory of piezoelectric semiconductors. In this method, two boundary value problems (BVPs) are solved iteratively. One is called the mechanical BVP, and the other is the semiconductor BVP. Piezoelectricity is used to link these two BVPs. The piezoelectric polarization charges are deeply taken into account in the bidirectional coupling of mechanical field and semiconductor. An experimental configuration is designed to determine the contact type, that is, Schottky contact or Ohmic contact. At the same time, the iterative method based on the commercial software COMSOL is employed to analyze this configuration numerically. A validation of the algorithm is conducted by comparing the experimental and numerical results. As an application, the electromechanical properties of a typical Ag-GaN piezoelectric semiconductor structure are investigated by the developed approach. The results revealed that it can be totally applied to analyze and predict the electromechanical properties of semiconductor materials with piezoelectricity.