Optimized ti and tin thin films for anti-reflective coatings in photolithography

Overview

The continuous scaling of semiconductor devices poses significant challenges in photolithography, particularly as feature sizes shrink below 0.20 μm. Optical reflections from interfaces lead to standing wave formation and critical dimension variations, undermining pattern fidelity. This research focuses on developing optimized Ti and TiN thin films as anti-reflective coatings (ARCs) to mitigate these issues. By employing advanced deposition techniques, these coatings enhance the performance of lithographic processes, ensuring greater precision in semiconductor manufacturing.

Technical specifications

Deposition Techniques:

• E-beam evaporation and sputtering methods are utilized for film fabrication.
• Key parameters include deposition rate, substrate temperature, vacuum pressure, and film thickness (20–100 nm).

Materials and Methods:

• Ti and TiN films are deposited on Si/SiO₂ substrates.
• Reactive DC/RF sputtering and e-beam deposition are used with parameters like N₂ flow ratio and chamber pressure.

Characterization Techniques:

• Crystal structure analysis via X-ray Diffraction (XRD).
• Surface morphology studied using SEM and AFM.
• Optical properties measured by ellipsometry and UV–Vis spectrophotometry.
• Electrical resistivity assessed using a four-point probe.

Technology readiness level

The technology is at TRL 2, indicating that the concept and application have been formulated, with initial lab-scale experiments underway to validate the approach and optimize conditions for industrial applications.