Study on the Efficiency Enhancement of Chemical Mechanical Polishing of Gallium Nitride by Acetic Acid

This study investigates the role of acetic acid (CH<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</inf>COOH) as a pH regulator in ceria-based slurries for chemical mechanical polishing (CMP) of gallium nitride (GaN) thin films. Through a series of experiments, it was discovered that the incorporation of CH<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</inf>COOH significantly enhances the material removal rate (MRR) up to 495.2 nm/h, representing a 70% increase compared to nitric acid. The resulting GaN surfaces exhibited exceptional smoothness with a surface roughness (Sq) of 0.07 nm. The findings offer promising insights for optimizing CMP processes for GaN applications in the semiconductor industry.