Selective Surface Passivation for Ultrathin and Continuous Metallic Films via Atomic Layer Deposition.

Area of Science:

• Materials Science
• Surface Chemistry
• Nanotechnology

Background:

• High surface energy of metals leads to island formation during film deposition, hindering continuous ultrathin film fabrication.
• Achieving smooth and continuous metallic films below a few nanometers is crucial for next-generation electronics.

Purpose of the Study:

• To develop a novel atomic layer deposition (ALD) strategy for fabricating ultrathin, continuous metallic films of iridium (Ir) and platinum (Pt).
• To investigate the use of an inhibitor to control nucleation and growth for improved film properties.

Main Methods:

• Implemented an inhibitor-modified atomic layer deposition (ALD) technique.
• Utilized aniline as a selective inhibitor adsorbed exclusively onto metallic surfaces.
• Controlled nucleation and growth of Ir and Pt on dielectric substrates.

Main Results:

• Successfully produced continuous ultrathin Ir films (<1 nm) and Pt films (<2.3 nm).
• The aniline inhibition strategy suppressed lateral growth and promoted new nucleation, leading to continuous films.
• Achieved significantly improved surface smoothness and reduced electrical resistivity compared to conventional ALD.
• Demonstrated effectiveness for precursors with significant nucleation delays.

Conclusions:

• The inhibitor-modified ALD strategy provides an effective method for fabricating ultrathin, smooth metallic films.
• This approach addresses challenges in producing high-quality metallic films for emerging electronic applications.
• Aniline's selective adsorption offers precise control over metal film growth at the nanoscale.