TWI Industrial Member Report Summary 825/2005
By D Kirkpatrick
Background
Flip chip bonding involves the use of a perimeter or area array of very short, micro-miniature metallic electrically conducting polymer bump connections between a device that is inverted in a flip chip orientation over a mirror image pad array on a substrate. Flip chip bonding thus offers a very high interconnection density device joining technology with very low electrical parasitics that is ideally suited for the assembly and interconnection of electronics, photonics and sensor devices to the supporting package, substrate or circuit board.
Flip chip accounted for some 5% of the 60 billion integrated circuit (IC) devices produced each year world-wide in 2002, with the remainder employing the more conventional technique of wire bonding. However, the proportion of ICs employing flip chip technology is now starting to increase significantly and predictions of over 10% flip chip utilisation by 2005 have been made. The expansion of flip chip technology is being driven primarily by the relentless increase in chip input/output (I/O) count, ever higher operating frequencies, pressure to achieve a very small form factor and the need to achieve the lowest possible first level packaging costs.
As this technology develops and grows, there is an urgent need to understand the many flip chip technology options available and the capabilities of the emerging global bumping and assembly infrastructure. Such an understanding will enable member companies to choose the technology best suited to their end applications. In addition, the establishment of an up-to-date flip chip technology capability at TWI will also provide a fast turn prototype facility to meet customers' product development needs and an entry route for companies wishing to adopt this important technology. The present programme on flip chip technology provided an underpinning support for these strategic activities. Significant project work and revenue in this area is targeted for 2004 and beyond.
Objectives
- To survey available and emerging flip chip technology options and the global markets and applications for the bumping and assembly of electronic, photonic and sensor devices; to identify the benefits and disadvantages of the different techniques; and to gauge the maturity of the bumping business.
- To demonstrate flip chip solder bonding assembly processes.