Materials Quest for Advanced Interconnect Metallization in Integrated Circuits

Area of Science:

• Materials Science
• Electrical Engineering
• Semiconductor Manufacturing

Background:

• Integrated circuit (IC) performance improvements are slowing due to increasing cost and complexity.
• Back-end-of-line (BEOL) processes lag behind front-end-of-line (FEOL) advancements.
• Chip speed is now limited by interconnect performance as transistor density increases.

Purpose of the Study:

• To review novel materials for nanoscale interconnects in advanced integrated circuits.
• To address the challenges posed by shrinking physical dimensions in interconnect structures.
• To bridge the gap between academic research and industrial application in interconnect materials.

Main Methods:

• Exploration of challenges in shrinking interconnect structures.
• Analysis of material properties for problem-solving in interconnects.
• Review of state-of-the-art studies on material characteristics and process applications.

Main Results:

• Identification of new barrier materials: 2D materials, self-assembled molecular layers, high-entropy alloys.
• Introduction of novel conductor materials: Cobalt (Co), Ruthenium (Ru), intermetallic compounds, MAX phases.
• Comprehensive discussion of material properties from theoretical calculations to practical process integration.

Conclusions:

• New materials are essential for overcoming interconnect limitations in scaled ICs.
• A materials-based strategy is proposed for implementing advanced interconnect solutions.
• The review provides a roadmap for industry adoption of novel interconnect materials.