Nanoscale particle removal using conventional and hybrid laser shockwave cleaning

Abstract

As surface contamination by submicron particulates becomes a critical issue in semiconductor industry, efforts have been made to develop noncontact effective laser-based cleaning techniques. The laser shockwave cleaning (LSC) process is one of the promising techniques that has been demonstrated to be effective for inorganic particle dry removal. In the cleaning process, the surface is not directly exposed to irradiation of laser beam, which eliminate the possibility of potential surface damage. In addition, a relatively large area can be cleaned by a single laser pulse. However, even though this technology has those distinct advantages, LSC technique has a difficulty in removing organic particles, which removal mechanism hasn't been found yet. Recently, the laser shockwave cleaning technique has been combined with ultraviolet (UV) laser for organic particle removal. But, when UV laser cleaning is used in this hybrid approach with LSC, optimization is required to ensure damage free cleaning. This is required whenever a new surface is used.