Title :
Investigation of low cost flip chip under bump metailization (UBM) systems on Cu pads
Author :
Jae-Woong Nab ; Paik, Kyung-Wook
Author_Institution :
Dept. of Mater. Sci. & Eng., Korea Adv. Inst. of Sci. & Technol., Seoul, South Korea
Abstract :
Cu is considered as a promising alternative interconnection material to Al-based interconnection materials in Si-based integrated circuits due to its low resistivity and superior resistance to the electromigration. New bumping and UBM material systems for solder flip chip interconnection of Cu pads were investigated using electroless-plated copper (E-Cu) and electroless-plated nickel (E-Ni) plating methods as low cost alternatives. Optimally designed E-Ni/E-Cu UBM bilayer material system can be used not only as UBMs for solder bumps but also as the bump itself. Electroless-plated E-Ni/E-Cu bumps assembled using anisotropic conductive adhesives on an organic substrate is successfully demonstrated and characterized in this study
Keywords :
chip-on-board packaging; copper; electroless deposited coatings; electroless deposition; flip-chip devices; integrated circuit interconnections; metallisation; microassembling; nickel; soldering; surface mount technology; Cu; Cu pads; Ni; Si; Si-based integrated circuits; anisotropic conductive adhesives; electroless-plated Cu; electroless-plated Ni; interconnection material; low cost flip chip UBM systems; organic substrate; plating methods; solder flip chip interconnection; under bump metailization systems; Anisotropic magnetoresistance; Assembly; Conducting materials; Conductivity; Copper; Costs; Electromigration; Flip chip; Integrated circuit interconnections; Nickel;
Conference_Titel :
Electronic Components and Technology Conference, 2001. Proceedings., 51st
Conference_Location :
Orlando, FL
Print_ISBN :
0-7803-7038-4
DOI :
10.1109/ECTC.2001.927871
