Competitive Adsorption as a Route to Area-Selective Deposition

Area of Science:

• Materials Science
• Surface Chemistry
• Thin Film Deposition

Background:

• Area-selective deposition (ASD) is crucial for advanced microelectronics fabrication.
• Controlling thin-film growth on complex substrates with multiple materials presents significant challenges.

Purpose of the Study:

• To develop a novel method for selective chemical vapor deposition (CVD) of thin films.
• To investigate the use of a coadsorbate to direct film growth exclusively onto one surface.

Main Methods:

• Utilized density functional theory (DFT) calculations and in situ surface analysis.
• Employed 4-octyne as a coadsorbate in the CVD of ZrO2 thin films.
• Investigated deposition on SiO2 and Cu surfaces.

Main Results:

• 4-octyne effectively blocked precursor adsorption on Cu surfaces at optimized conditions.
• Selective dielectric-on-dielectric (DoD) deposition of ZrO2 on SiO2 was achieved without growth on Cu.
• The process demonstrated high selectivity, speed, and preservation of film composition and morphology.

Conclusions:

• The coadsorption strategy using 4-octyne enables highly selective CVD.
• This vapor-phase, area-selective deposition method is potentially widely applicable for various material systems.
• Identifying suitable preferential binding agents is key for broader implementation.