Development of high-performance wafer adhesive cleaning solution for AVP process

초록

High performance etchant solution is developed to effectively remove the polydimethylsiloxane (PDMS) residues from semiconductor advanced packaging (AVP) process. It is known that fluorine-containing polar solution, such as tetrabutylammonium fluoride (TBAF) dissolved in polar solvent, can etch the PDMS residue, however, none of study has investigated the enhancement of PDMS etching upon the addition of non-polar solvent serving as a swelling agent. In this study, we have focused on enhancing the etching rate of PDMS by preparing the new developed etchant solution mixing of TBAF, polar solvent, and non-polar swelling agent. The concentration of TBAF and non-polar swelling agent is controlled as .0?5.0 wt% and 0.0?90.0 wt%, respectively, to optimize the etching performance. It is demonstrated that high etching rate of PDMS achieved using 3.0 wt% TBAF and 70.0 wt% pentane, attributed to the simultaneous swelling and chemical etching action of the non-polar solvent and fluoride ions, along with the etching assistance provided by the polar solvent. The practical application of the new-developed etchant solution is verified that PDMS residue is completely removed in short time from pattern wafers without damaging protective layers such as PSPI. This study presents the selective and etching performance of PDMS residue in AVP and similar semiconductor packaging processes, demonstrating the potential of swelling-assisted etching to enhance process reliability. Keywords : Non-polar swelling agent, etchant solution, PDMS, etching performance, Advanced packaging. †Corresponding Author: cmyoon4321@inha.ac.kr