Surfactant-Mediated Non-Contact Dual Jet Cleaning for Post-CMP
Wafer Surface
Wafi Aziz
MS Candidate, Chemical and Biomolecular Engineering
Clarkson University
The semiconductor industry is at the heart of technological advancement, driving innovations in
computing, communication, and automation. And the demand for miniaturization in electronics, alongside the growing complexity of integrated circuits, has made chemical mechanical planarization (CMP) a critical step which is used multiple times in the semiconductor manufacturing process at each layer of the wafer to create a smooth surface. However, CMP often leaves behind a variety of contaminants including particulates, residue, pad debris, and various impurities on the wafer surface. It is crucial to remove these contaminants from the wafer surface during the post-CMP cleaning, while also minimizing the formation of surface scratches. Cleaning solutions, often used along with brush cleaning, are highly efficient, but pose challenges such as cross-contamination, surface scratching, and particle residues. In post-CMP cleaning, especially for ceria particles, the typical cleaning solution contains a bond-breaking reagent, a complexing reagent, a cleaning additive, and a pH adjuster. And surfactants are extensively used as cleaning additives, where they interact with films and particles to prevent the redeposition of particles during the cleaning.
In this research, we investigated how the charge of surfactants and their critical micelle concentration
(CMC) affect particle removal during the cleaning process. We employed a non-contact dual jet cleaning
method to mitigate issues like cross-contamination and surface scratching. Our results showed effective
cleaning performance across an 8-inch wafer, using solutions with anionic surfactants through the dual jet
cleaning process. Additionally, this non-contact method helps avoid cross-contamination, reduces the risk
of damaging the wafer surface, and enhances overall cleaning effectiveness. These findings provide
valuable insights, thereby aiding in the development of improved cleaning protocols in the semiconductor industry.
Thursday, July 25, 2024, at 10:00 am
CAMP 372
Wafi Aziz is a MS student in Chemical and Biomolecular Engineering at Clarkson University under the supervision of Dr. Jihoon Seo. Prior to joining Clarkson University, he received his Bachelor of Science in Chemical Engineering from Bangladesh University of Engineering and Technology. His research focuses on Chemical Mechanical Planarization (CMP) and Post-CMP cleaning techniques of Semiconductor
wafers.