PARIS – Gold bumping may be the preferred attachment method for flip chip today, but that’s not going to be the case much longer, a new research report says.

Gold bumping will be overtaken due to a slowdown in growth of the primary product it is used for – LCD driver ICs – and the high raw material cost, Yole Développement says.

In its place, copper pillar bumping will jump from the second most popular flip chip attachment method. Cu bumping is preferred by Intel, the world leader in wafer bumping capacity.

Other methods, including tin-lead and lead-free solder bumping, are less significant in terms of popularity, Yole said in a webinar today. Yole, which is releasing a research report on flip chip market and technologies, noted lead will be banned in 2014, boosting Cu pillar.

“The next big technology is clearly going to be Cu pillar,” said Jean-Marc Yannou, a project manager with Yole.

At stake is a big market: total flip chip sales, including assembly, packaging and test, reached $16 billion in 2010, Yole said, good for 29% of the worldwide IC market. Of that, assembly made up 14% and final test 17%. Yole estimates $5.4 billion worth of PCB substrates were used for flip chip in 2010, with BT and FR-4 materials (at less than $2 billion in 2010) the main materials.

Fabricators and assemblers of plated bumps or rigid organic substrates designed for flip chips have much to look forward to over the next few years. Yole forecasts package unit sales will grow 19.6% compounded annually between 2010 to 2016.

The top end-markets for flip chips are computing and telecom, in that order, but that is changing, Yole said. As of this year, the firm expects telecom to surpass computing. Other markets, including consumer, industrial, automotive and military/aerospace, are considerably small in terms of value. Nevertheless, flip chip has been used in the automotive sector for years, primarily on ceramic substrates, where it is preferred for its stability. “It is sometimes better than wire bonding for reliability and electromigration,” noted Yannou.

As noted, Intel maintains the lead in wafer bumping capacity, followed by ChipBond, TSMC, Samsung, NEPES and ASE. By geography, Taiwan holds the greatest share with 38%, followed by the US (24%), and Korea (17%).

One newer trend Yole is seeing is use of flip chip for memory, albeit the overall volume remains low. While still rare, Yannou said, DRAMS used for GPUs were first produced in significant volumes late last year. “It’s been forecasted by some [and] we do think there will be more of these, but as of today, it’s not significant.”