Preparation of CNT-copper matrix composite films

Area of Science:

• Materials Science
• Nanotechnology
• Electrochemistry

Background:

• Developing advanced composite materials with enhanced properties is crucial for electronic applications.
• Multiwall carbon nanotubes (CNTs) offer exceptional mechanical and electrical characteristics for material reinforcement.
• Electroplating is a versatile technique for fabricating thin films and composite structures.

Purpose of the Study:

• To investigate the fabrication and properties of copper matrix composite thin films reinforced with multiwall carbon nanotubes (CNT-Cu-MC).
• To evaluate the effect of CNT reinforcement on the microstructure and electrical properties of electroplated copper films.
• To explore methods for enhancing interfacial strength between CNTs and the copper matrix.

Main Methods:

• Fabrication of CNT-Cu-MC films via electroplating on Si substrates with iron catalyst particles.
• Growth of CNTs using thermal or plasma-enhanced catalytic chemical vapor deposition (CVD).
• Application of plasma-enhanced atomic layer deposition (PEALD) for CNT surface modification with Ta-N or Ta-N/Zr-O interlayers.
• Copper plating using a conventional copper electrolyte with additives.

Main Results:

• Enhanced interfacial strength achieved by PEALD of Ta-N or Ta-N/Zr-O interlayers on CNTs.
• Quality of composite films is primarily determined by CNT density and growth.
• Sufficient dispersion and homogeneous copper plating obtained at low CNT densities.
• CNT reinforcement alters the microstructure and increases the electrical resistivity of electroplated copper films.

Conclusions:

• Electroplating is a viable method for producing CNT-Cu-MC composite films.
• Interfacial engineering using PEALD is effective in improving CNT-copper adhesion.
• CNT reinforcement significantly impacts the microstructure and electrical resistivity of copper films, offering potential for tailored material properties.