Experimental Investigation of Semiconductor Barriers Exposed to Variable Strong Electric Field at Vacuum Conditions

Abstract

This study investigates alternating current barrier discharges in Townsend, glow, and arc modes when the barrier constitutes a semiconductor. First, the electrical characteristics of the reactor, with a specific electrode configuration, and the effect of the semiconductor on plasma formation are examined. Subsequently, the surface and structure of the semiconductor barriers, processed for the three modes, are analyzed at an atomic scale. The results indicate that the plasma produced within the semiconductor barrier discharge (SBD) system exhibits higher homogeneity. Notably, the barrier is active in the Townsend mode. In proportion to the voltage applied to the SBD system, the semiconductor diminishes its barrier property, and the influence of the semiconductor barrier loses upon reaching approximately 1 kV. The plasma becomes inhomogeneous in arc mode, and strong current channels become prominent, leading to substantial degradation of the semiconductor barrier. Furthermore, the proposed electrode configuration presents properties characteristic of a Schottky diode. Ultimately, the electrical equivalent circuit of the reactor demonstrates similarities with a varactor structure. The SBD system's electronic structure and filtering feature could potentially contribute to the future conception of self-controlled BD systems.