Numerical simulation of electron-beam-induced gate currents in a GaAs MESFET. II. Numerical and experimental results

Abstract

Metal-semiconductor field-effect transistors (MESFETs) are important semiconductor devices, which can be produced on many semiconductor materials. Owing to their simple structure, MESFETs are often used as pioneering devices when new material systems are developed. Electron-beam-induced gate current (gate EBIC) measurements in a scanning electron microscope (SEM) can be used as an important tool for investigating the electrical homogeneity of semiconductor materials, electrical contacts and process-induced defects in MESFETs. Furthermore, in combination with suitable simulations, a profound understanding of the importance of different material and device parameters to the electron-beam-induced currents is possible. With this aim, results of two-dimensional numerical gate EBIC simulations obtained for a GaAs MESFET are presented in this paper and partially compared with measured line scans.