The first atomic layer deposition process for Fe_xN films.

Area of Science:

• Materials Science
• Nanotechnology
• Chemical Engineering

Background:

• Atomic Layer Deposition (ALD) is crucial for thin film fabrication.
• Iron nitride (FexN) films have diverse applications but require efficient deposition methods.
• Developing conformal ALD processes for complex 3D structures remains a challenge.

Purpose of the Study:

• To report the first efficient ALD process for FexN films.
• To investigate the self-limiting growth characteristics of the ALD process.
• To demonstrate the conformal deposition of FexN films on high-aspect-ratio trench substrates.

Main Methods:

• Utilized Bis(N,N'-di-tert-butylacetamidinato)iron(ii) (Fe(tBu-amd)2) and anhydrous hydrazine (N2H4) as precursors.
• Investigated reactant dose and cycle number effects on growth rate for self-limiting behavior.
• Employed first-principles calculations to elucidate the reaction mechanism.

Main Results:

• Achieved ideal self-limiting growth for FexN films.
• Demonstrated conformal and uniform FexN film growth on trench substrates with an aspect ratio of 2.5:1.
• Proposed a reaction mechanism based on experimental and computational studies.

Conclusions:

• The developed ALD process is efficient and suitable for FexN film deposition.
• The process shows significant potential for nanoengineering complex 3D and porous structures.
• This work is expected to advance FexN-based nanoengineering and its applications.