Title :
Low cost flip chip technology for organic substrates
Author_Institution :
Fujitsu Labs. Ltd., Kawasaki, Japan
Abstract :
This paper describes outline of the flip chip technology which is used on various kind of substrates (glass-epoxy, flexible Printed Circuit Board, and MCM-L/D). In this technology, Au bumps are formed on the chip I/O pads by wire bonding method, and the bumps are pressed against the substrate pads. The chip is bonded and encapsuled with a thermosetting adhesive, and conductive paste assists mechanical and electrical connection between the Au bumps and the substrate in order to increase the connection reliability. To apply this technology to different types of substrates, we surveyed the deformation characteristic of the substrate pad and the characteristic of the adhesive for encapsulation (adhesion strength and insulation). This technology has been applied to some practical products and the mounting areas of LSI become 1/10 or less compared with existing SMD package approach
Keywords :
adhesion; encapsulation; flip-chip devices; integrated circuit packaging; integrated circuit reliability; large scale integration; lead bonding; multichip modules; Au; LSI; MCM-L/D; adhesion strength; conductive paste; connection reliability; deformation characteristic; encapsulation; flexible printed circuit board; flip chip technology; organic substrates; thermosetting adhesive; wire bonding method; Adhesives; Bonding; Costs; Encapsulation; Flexible printed circuits; Flip chip; Gold; Insulation; Large scale integration; Wire;
Conference_Titel :
Electronic Components and Technology Conference, 1997. Proceedings., 47th
Conference_Location :
San Jose, CA
Print_ISBN :
0-7803-3857-X
DOI :
10.1109/ECTC.1997.606180
