Study on the Electro-Fenton Chemomechanical Removal Behavior in Single-Crystal GaN Pin-Disk Friction Wear Experiments

Area of Science:

• Materials Science
• Surface Chemistry
• Tribology

Background:

• Electro-Fenton polishing utilizes hydroxyl radicals (·OH) generated via the Fenton reaction and an electric field.
• This process influences oxide layer formation and removal, impacting polishing quality and rate.
• Understanding material removal mechanisms is crucial for advanced semiconductor manufacturing.

Purpose of the Study:

• To investigate the material removal behavior of single-crystal Gallium Nitride (GaN) during electro-Fenton chemical mechanical polishing.
• To analyze the influence of key parameters like abrasives, pads, and pressure on the polishing process.
• To provide insights into the synergistic removal mechanisms in electro-Fenton chemical-mechanical polishing of GaN.

Main Methods:

• Pin-Disk friction and wear experiments were conducted on single-crystal GaN.
• Analytical techniques included coefficient of friction (COF) curves, surface morphology, cross-sectional analysis, and power spectral density (PSD) measurements.
• Systematic variation of abrasives, polishing pads, and pressure was employed.

Main Results:

• Optimal material removal was identified under specific conditions: W0.5 diamond abrasives at 1.5 wt% concentration and a urethane pad (SH-Q13K-600).
• A polishing pressure of 0.2242 MPa was found to be optimal for mechanical removal.
• The study examined the interplay between mechanical and chemical actions in the electro-Fenton process.

Conclusions:

• The study successfully identified optimal parameters for electro-Fenton chemical mechanical polishing of single-crystal GaN.
• The findings contribute to understanding synergistic material removal mechanisms in this advanced polishing technique.
• This research offers valuable data for optimizing GaN wafer processing and achieving high-quality surfaces.