In-Situ Characterization of Plasma Species for Process Optimization and Improvement

Plasma treatments are widely known and used in physical chemistry, chemical engineering, polymer science, biomedicine, semiconductor fabrication, etc. In semiconductors, plasma-air interactions are commonly used in front-end and back-end processes, the understanding of plasma reactive species within plasma treatments is still very limited and at an early stage. Their interaction between ionized species, radicals, plasma atoms and sample chemical composition is still unknown. The challenge is to selectively produce actives species beforehand identified. A better understanding of species within a plasma could lead to considerable improvements in terms of efficiency and throughput. This paper begins with a description of the methodology used to characterize plasma. This is followed by a deep study of the targeted chemistry of different back -end processes and their possible optimization. Finally, an optimized recipe is suggested for some back-end processes such underfilling, molding and wirebonding.