Phase transformation in SiOx/SiO₂ multilayers for optoelectronics and microelectronics applications.

Area of Science:

• Materials Science
• Nanotechnology
• Solid State Physics

Background:

• Silicon nanoclusters (Si-ncs) are vital for advanced optoelectronics and microelectronics due to quantum confinement effects.
• SiO(x)/SiO₂ multilayers offer a promising platform for embedding Si-ncs, requiring controlled fabrication and annealing processes.

Purpose of the Study:

• To investigate the phase separation and nanocluster formation in SiO(x)/SiO₂ multilayers.
• To elucidate the influence of key parameters on the resulting microstructure of Si-ncs.

Main Methods:

• Fabrication of SiO(x)/SiO₂ multilayers using magnetron sputtering.
• Annealing treatments to induce phase separation and Si-nc growth.
• Atom probe tomography (APT) for high-resolution microstructural analysis.

Main Results:

• Silicon supersaturation dictates the phase separation mechanism (nucleation/growth vs. spinodal decomposition).
• Annealing temperature governs Si-nc size and their interfacial properties with the matrix.
• Layer thicknesses influence Si-nc morphology, ranging from spherical to spinodal-like structures.

Conclusions:

• Precise control over fabrication and annealing parameters is essential for tailoring Si-nc properties in SiO(x)/SiO₂ multilayers.
• Atom probe tomography provides critical insights into the complex nanoscale phenomena governing Si-nc formation.
• This study offers a pathway for optimizing Si-nc embedded dielectric materials for future electronic and photonic devices.