An Independent Journal Dedicated to the Advancement of Chip - Scale Electronics July - August 2000 Email the editor

Chip Scale Review asked users of IC assembly services what they look for in selecting a vendor. The number one answers were "customer support," and "certification to ISO 9000/9001" standards. Price, in most cases, hobbled in a poor fourth or fifth. By Ron Iscoff, Editor Figure 1. Fairchild's assembled devices include this 5-lead, SC - 70 package.

While it often seems that everybody-users and vendors of IC assembly services alike-is always talking about the cost-per-pin for IC package assembly, that's not the key reason to select a supplier, according to our small, unscientific survey.

We asked many IC assembly buyers to complete a brief survey that we designed. While we didn't receive a lot of responses, the ones we did get are telling.

Dr. Martin Goetz is director of packaging technology at Alpine Microsystems, Campbell, Calif. Alpine operates a flip-chip assembly and packaging line for direct attach, silicon-based, system-in-a-package products.

Dr. Goetz notes that Alpine employs subcontractors when manufacturing complex IC substrates that are subsequently wire bonded into BGA packages.

"The subcontractors are set up to perform wire bonding and encapsulation at the time we needed that type of package." Alpine looks to subcontractors for high- volume production of DCA packages to save labor costs and because they have an existing infrastructure.

'Technically Superior Development Team'

Alpine's selection criteria includes, "technically superior development teams. They must be able to handle flip-chip ICs and have comprehensive testing capability, as well as volume capacity or expansion capability," he adds.

In the future, Dr. Goetz plans to use more contract IC assembly, he says. "Alpine's business model is to create intellectual property, develop the processes and transfer and/or license the technology to a manufacturing partner for volume. Alpine will maintain the IP, and will be the exclusive customer for most products."

Legendary semiconductor maker Fairchild operates its own IC assembly plants in Malaysia and the Philippines. Together, these facilities handle about half of Fairchild's IC packaging needs (Figure 1).

Extra Capacity

The company contracts with outside IC assemblers when it needs extra capacity and when it requires specialty packaging, according to Lim Quek Cheng, planning and customer service manager at Fairchild Semiconductor (Malaysia) Sdn Bhd.

Figure 2. This tiny analog device is among National Semiconductor-assembled parts.

National Semiconductor, Santa Clara, Calif., assembles about 80 percent of the ICs it produces in its own facilities and contracts the balance (Figure 2).

Like Fairchild, National employs subcontractors for extra capacity and for specialty packaging. "It's our philosophy to fill our plants to capacity and to run the overflow outside," reports Sharon Ignaut, standard analog products engineering manager.

Different Criteria

Ignaut says there are different criteria for subcontractor selection, depending on whether National needs the vendor to handle extra capacity or to help develop a new package.

"When we're looking for extra production capacity, the primary considerations are manufacturing skills, cycle time, quality and responsiveness. If the overall performance of the vendors is equal, then cost becomes the primary consideration.

"When we are looking for a joint development effort with a subcontractor, the primary considerations are strong engineering skills and reliability," she says.

Future Plans

Asked whether National would use more, less or about the same amount of outside assembly help in the future, Ignaut responded that "our business model for this strategy indicates the optimum cost benefit to be at an 80/20 mix. We may shift to a 75/25 (National/subcontractor) in the future, but not greater than that."

NEC Electronics, Roseville, Calif., handles 80-90 percent of its IC packaging needs in Roseville, and at its plants in Japan and elsewhere.

The reasons to employ an outside IC assembler are for specialty packaging needs and to save money over internal packaging (though not specifically labor costs), reports Han Park, packaging engineering manager in Roseville.

NEC's key vendor selection criteria are, first, the high-end packaging capacity of the vendor, following by quality control. "Quality control must adhere to NEC's exacting standards," Park emphasizes.

"The vendor must also be highly reliable and must have package design capabilities. "Design capability is an important issue," Park adds, as are thermal and electrical characterization capabilities.

Conclusion

Overall, our survey respondents told us what they want (see table, top right). While price is always a matter of some concern in highly competitive world markets, customer support and international quality certification are considered mandatory by our user sample.