Group-III nitride heteroepitaxial films approaching bulk-class quality

Area of Science:

• Materials Science
• Solid State Physics

Background:

• III-nitride wide bandgap semiconductors are crucial for advanced electronics and optoelectronics.
• Heteroepitaxial film quality has improved but still lags behind bulk crystals.

Purpose of the Study:

• To present a novel paradigm for achieving high-quality III-nitride heteroepitaxial films.
• To overcome limitations in current III-nitride film growth.

Main Methods:

• Utilizing nano-patterned AlN/sapphire templates with hexagonal holes.
• Employing sapphire nitridation pretreatment for uniform orientation.
• Controlling column discretization and coalescence for ordered lateral growth.

Main Results:

• Achieved uniform out-of-plane and in-plane orientations of coalescing AlN columns.
• Efficiently suppressed threading dislocation regeneration during coalescence.
• Reduced dislocation etch pit density to 3.3 × 10^4 cm^-2, approaching bulk AlN crystal quality.

Conclusions:

• The developed method enables the growth of bulk-class quality III-nitride films.
• This approach offers a scalable and cost-effective solution for high-performance semiconductor materials.