How Can UWBG Analysis Benefit Your Research?
Ultra-wide bandgap (UWBG) semiconductors are garnering significant interest in the field of materials science due to their promising electrical and thermal properties. However, challenges persist in material quality and fabrication. This blog post will discuss the promise of UWBG semiconductors, the roadblocks to their implementation, and how analytical technologies – particularly cathodoluminescence (CL) – can help overcome these issues and hopefully usher in higher-quality semiconductors for research applications.
Discovering the Potential of Ultra-Wide Bandgap Semiconductors
UWBG semiconductors are materials with a bandgap energy greater than 3 electron volts (eV). Examples include boron nitride, diamond, and gallium oxide. These materials exhibit superior electrical and thermal properties compared to traditional wide bandgap semiconductors, making them ideal for high-power, high-temperature, and high-frequency applications.
Tackling the Challenges and Roadblocks in UWBG Implementation
Despite their potential, UWBG semiconductors face several challenges. Material defects are a particularly galling issue. However, doping poses an ongoing issue, as does the fabrication of reliable device architectures. Overcoming these myriad roadblocks is essential to implementing UWBG devices for research purposes. Material defects can lead to increased leakage currents and reduced breakdown voltage, hindering end-device performance. Additionally, doping UWBG materials can be challenging due to the need for high-quality crystals and the difficulty of incorporating dopant atoms.
Empowering Research with Advanced Analytical Technologies
To overcome these UWBG manufacturing challenges, researchers can employ analytical technologies for quality assurance and quality control (QA/QC). One such technology is cathodoluminescence (CL), an analytical technique used to study the composition, optical properties, and electronic properties of materials at the micro- and nanoscale.
CL involves the excitation of a material using an electron beam, causing it to emit light. This emitted light contains information about the material’s internal structures, optical properties, and trace elements. CL imaging can thus provide valuable insights into the material’s defects and variations at high spatial resolution, making it an extremely powerful tool for UWBG semiconductor analysis.
How CL Factors h to UWBG Semiconductor Quality Control
Cathodoluminescence is particularly useful for UWBG semiconductor analysis because conventional photoluminescence methods cannot be applied to these materials, as they are transparent at the wavelengths commonly used in process development. CL can be integrated with electron microscopy techniques such as scanning electron microscopy (SEM), transmission electron microscopy (TEM), or scanning transmission electron microscopy (STEM) for comprehensive analysis.
In one example, CL was used to analyze hexagonal boron nitride (h-BN), a UWBG semiconductor with a bandgap of ~5.5 – 6.0 eV. A focused electron beam in an SEM was used to excite electron-hole pairs in the h-BN, and a Gatan Monarc Pro cathodoluminescence system was employed to capture and analyze the radiative decay of excess carriers, resulting in the emission of photons.
Enabling Next-Generation Semiconductors through CL Analysis
CL imaging and analysis allow researchers to map defects and variations in UWBG semiconductors at the nanoscale, which is crucial for developing high-quality materials for semiconductor devices. By identifying and understanding these defects, researchers can optimize the material growth process and improve the performance of devices based on UWBG semiconductors.
UWBG semiconductors hold significant promise for a range of high-power, high-temperature, and high-frequency applications. However, challenges in material quality and fabrication must be overcome to unlock their full potential. Cathodoluminescence serves as a valuable analytical solution for addressing these challenges, helping researchers develop higher-quality semiconductors. Want to learn more? Contact us today.
