Advanced characterization of SiC devices by optical beam induced current (OBIC): Experimental and simulation results

Abstract

Wide-bandgap semiconductors, such as silicon carbide (SiC), gallium nitride (GaN), and diamond (C), have proven to outperform traditional silicon (Si) based power electronic devices. However, the peripheral protection of these wide-bandgap devices requires careful design to handle high voltage effectively. This article highlights the potential of using the Optical Beam Induced Current (OBIC) technique to analyze the effectiveness of different protection methods and provide valuable feedback to device designers regarding peripheral termination efficiency. Designers need simulations representative of the measurement, In this article a finite element simulation is used to determine the induced current as a function of the position of the optical beam.Firstly a theoretical approach will be presented to introduce the OBIC method. Subsequently, the electro-optical characterization technique is applied to a PiN diode protected by narrow field rings.The article also showcases new results obtained from components with new-generation peripheral protection, demonstrating the continuous progress in this field.Overall, this article highlights the significance of the OBIC technique in evaluating the effectiveness of peripheral protection methods for wide-bandgap semiconductors, particularly SiC devices. By providing valuable insights into the electric field's spatial distribution, this technique aids in optimizing device design and improving overall performance. Finite element simulations in relation to the characteristics of the UV beam and its scanning across the surface of the component help to assess the geometric parameter impact on the electrical results.