Selective ion-induced intermixing and damage in low-dimensional GaN/AlN quantum structures.

Area of Science:

• Materials Science
• Solid State Physics
• Nanotechnology

Background:

• GaN/AlN superlattices are crucial for optoelectronic devices.
• Understanding ion-induced effects is vital for device fabrication and stability.

Purpose of the Study:

• To investigate ion-induced intermixing and damage in GaN/AlN quantum dots (QDs) and quantum wells (QWs).
• To compare the intermixing efficiency and damage accumulation between QDs and QWs.

Main Methods:

• 100 keV Ar(+) ion implantation at low temperature (15 K).
• Analysis of elemental depth profiles using a diffusion model.
• Evaluation of damage accumulation at varying ion fluences.

Main Results:

• Similar damage accumulation at low fluences, but significantly higher for QDs at high fluences.
• QD superlattices exhibit higher intermixing efficiency compared to QWs.
• Diffusion length scales with local fluence and defect concentration, explained by cascade mixing and defect migration.

Conclusions:

• Selective intermixing and damage in QDs are attributed to promoted lateral diffusion and enhanced diffusivity from strain distribution.
• These findings provide insights into controlling ion-beam processes for nanostructure engineering.