GaN Interlayer Design to Fully Eliminate V-Pits from InGaN Pseudo-Substrates
Tech ID: 32267 / UC Case 2020-707-0
Current GaN-based LEDs suffer from a lattice mismatch between the GaN buffer layer and the InGaN quantum wells (QWs), causing them to experience a low efficiency. In addition, low miscibility of Indium in InGaN, alloy fluctuations, and phase separation demands require a lower growth temperature of InGaN QWs which results in defects and material deterioration. Although c-plane InGaN pseudo-substrates afford the opportunity to provide an alternative platform for long-wavelength-emitting optical devices, the main challenge in growing such InGaN pseudo-substrates is the formation of V-pits as they are detrimental for subsequent material growth and device fabrication.
Researchers at the University of California, Santa Barbara have designed a GaN interlayer that completely eliminates V-pits from InGaN pseudo-substrates. In this technology, buffer layers comprised of InGaN layers and GaN interlayers are grown on the InGaN pseudo-substrate. Growth parameters for the InGaN layers and GaN interlayers work to enhance Ga atom diffusion to the V-pits on sidewalls of the InGaN pseudo-substrate.
- Elimination of V-pits
- Enhanced Ga atom diffusion