Breakthrough: Superior GaN-like Material Produced with MOCVD

Aluminum yttrium nitride (AlYN) is a material with excellent properties that hold great potential for use in energy-efficient high-frequency and high-performance electronics. Despite its close crystal lattice match to gallium nitride (GaN), AlYN has previously only been produced using magnetron sputtering, limiting its application in high volume manufacturing.

However, a significant breakthrough has been achieved by the Fraunhofer Institute for Applied Solid State Physics IAF. Researchers at the institute have successfully fabricated AlYN using metal-organic chemical vapor deposition (MOCVD) technology. This advancement opens up new possibilities for the development of innovative applications in the field of electronics.

"AlYN is a material that enables increased performance while minimizing energy consumption, paving the way for innovations in electronics that our digitally connected society urgently needs," stated Stefano Leone, a scientist at Fraunhofer IAF specializing in epitaxy.

Recent studies have revealed that AlYN exhibits ferroelectric properties, positioning it as a potential candidate for non-volatile memory semiconductor applications. This discovery further underscores the versatility and promise of AlYN in the realm of advanced electronics.

In a groundbreaking development in 2023, the Fraunhofer IAF research group successfully deposited a 600nm-thick AlYN layer with a wurtzite crystal structure containing over 30 percent yttrium. Subsequent efforts led to the creation of AlYN/GaN heterostructures with precisely adjustable yttrium concentrations, boasting exceptional structural quality and electrical properties.

Leone emphasized the remarkable values observed for sheet resistance, electron density, and electron mobility in these heterostructures, highlighting the immense potential of AlYN for high-frequency and high-performance electronics. The ability of AlYN/GaN heterostructures to induce a two-dimensional electron gas (2DEG) further enhances their appeal for semiconductor component development.

Moreover, the research results from Fraunhofer IAF demonstrate the optimal 2DEG properties in AlYN/GaN heterostructures at an yttrium concentration of approximately 8 percent, showcasing the material's suitability for advanced electronic applications.

While the successful growth of AlYN/GaN heterostructures on 4-inch SiC wafers in a commercial MOCVD reactor marks a significant milestone, challenges remain, particularly regarding AlYN's susceptibility to oxidation. To address this issue, researchers are exploring the use of high-purity precursor materials, protective coatings, and modifications to manufacturing techniques as potential solutions for further research.

For more information, visit Fraunhofer IAF.

Reference: Leone et al. “Metal-Organic Chemical Vapor Deposition of Aluminum Yttrium Nitride”, Phys. Status Solidi RRL 17 2300091 (2023) DOI Link

Additionally, Fraunhofer IPMS has collaborated to establish a European semiconductor metrology technology hub, further solidifying the commitment to advancing semiconductor research and development in the region.