PC-Tue-P44 - Investigation of wide-bandgap semiconductor materials by optical defect spectroscopy and THz-TDS
2. Physics and characterizationKuei-Shen Hsu2, Joshua Hennig3, Daniel Molter3, Jan Beyer2, Franziska C. Beyer1, Johannes Heitmann4
1 Fraunhofer Institute for Integrated Systems and Device Technology IISB, Schottkystr. 10, 91058 Erlangen, Germany
2 TU Bergakademie Freiberg, Institute of Applied Physics, Leipziger Str. 23, 09599 Freiberg, Germany
3 Fraunhofer Institute for Industrial Mathmatics ITWM, Fraunhofer-PLatz 1, 67663 Kaiserslautern, Germany
4 Fraunhofer Institute for Integrated Systems and Device Technology IISB, Schottkystr. 10, 91058 Erlangen, Germany; TU Bergakademie Freiberg, Institute of Applied Physics, Leipziger Str. 23, 09599 Freiberg, Germany
Abstract text
Wide-bandgap semiconductor materials, such as Gallium Nitride (GaN), Silicon Carbide (SiC) or Aluminium Nitride (AlN), are crucial for high-power and high-frequency electronic devices, as well as optoelectronic applications, including light-emitting diodes (LEDs) and laser diodes, due to their superior physical properties. Since carrier density and mobility are important parameters that significantly influence the performance of semiconductor devices, spatially resolved measurements are of increasing interest for non-destructive testing and mapping.
The THz time-domain spectroscopy (THz-TDS) is a well-established technique which can probe the dielectric properties of materials in the THz region on the one hand. On the other hand, optical defect spectroscopic methods, such as micro-Raman scattering or photoluminescence spectroscopy (PL), provide insights into vibrational properties, crystal quality, and defect states. The combination of both optical defect spectroscopy and THz-TDS characterization facilitates a comprehensive analysis of wide-bandgap semiconductors.
In this study, the relationships between structural defects, carrier dynamics, and overall material performance are evaluated by correlating the vibrational, defect spectroscopic and electronic properties derived from the applied techniques. The results will be discussed in terms of semiconductor quality as well as electrical homogeneity and are complemented by electrical measurements (e.g., C-V). The integrated approach which is presented is essential for advancing the development of next-generation electronic and optoelectronic devices based on wide-bandgap semiconductor materials, ultimately leading to improved efficiency and functionality in various applications.
This work was financially supported by the German Federal Ministry of Education and Research (BMBF) within the grants GaN-Digital (grant no. 13XP5189B) and Nitrides-4-6G (grant no. 16KISK134) as well as the German Federal Ministry of Economic Affairs and Climate Action (BMWK) within the ZIM project THz-SEMICON under grant no. KK5248101KK1.