Parasitic pre-reactions are known to play a role in the growth of aluminum nitride (AlN) via metal organic chemical vapor deposition, where they can deplete precursor molecules before reaching the substrate, leading to poor growth efficiency. Studies have shown that reducing the growth pressure and growth temperature results in improved growth efficiency of AlN; however, superior crystal quality and reduced impurity incorporation are generally best obtained when growing at high temperatures. This study shows that, with proper alkyl source dilution, parasitic pre-reactions can be suppressed while maintaining high growth temperatures. The results show an 18increase in growth rate and efficiency of AlN films: from 0.04 μm h-1 to 0.73 μm h-1, and 26 μm mol-1 to 502 μm mol-1, respectively; under constant TMAl flow and a small change in total gas flow. This results in 6.8% of Al atoms from the injected TMAl being utilized for AlN layer growth for this reactor configuration. This is better than the standard GaN growth, where 6.0% of the Ga atoms injected from TMGa are utilized for GaN growth.
Bibliographical noteKAUST Repository Item: Exported on 2021-07-16
Acknowledgements: This work was supported by the King Abduallah Center for Science and Technology-King Abdullah University of Science and Technology-University of California, Santa Barbara Solid State Lighting Program (KACST-KAUST-UCSB SSLP). The authors would like to the Materials Research Laboratory (MRL), California Nanosystems Institute (CNSI), and the Nanofabrication facility at UC Santa Barbara for providing access and training to their laboratories.
This publication acknowledges KAUST support, but has no KAUST affiliated authors.
ASJC Scopus subject areas
- Materials Chemistry
- Electronic, Optical and Magnetic Materials
- Electrical and Electronic Engineering
- Condensed Matter Physics