The demand for new electronic products, from powerful PCs to communications equipment, continues to grow. Consumption of semiconductors—the major performance-determining ingredient common to all these products—has been soaring.
Annual worldwide sales growth of ICs has increased by more than 29% in each of the last two years. It is expected to be at a less dynamic, but still respectable, rate of 15.6% in 1995.
The actual or perceived need for portable equipment is a major force driving this market. “Laptop computers and portable communication and entertainment devices are excellent examples of the type of equipment currently in demand; ones that command the highest price and greatest percentage of the market growth,” observed Jack Jania, with the Product Marketing Group at Advantest.
To achieve miniaturization—the prime requirement for realizing portability—manufacturers rely on higher circuit integration and surface-mount technology (SMT). But ICs embodying myriads of functions and the needed memory require longer test times. And more SMT device packages are continually evolving to accommodate the higher pin counts required by these complex ICs.
Higher production volumes, longer test times and new handling requirements are potential positives for the handler industry. Most of today’s semiconductor-industry forecasters agree that solid growth is ahead for the rest of this decade, but semiconductor suppliers are cautious. Whenever possible, they postpone building new facilities to accommodate additional equipment. They would rather upgrade existing equipment or purchase new equipment that makes better use of existing floor space.
To satisfy this need, handlers must deliver higher throughput per unit of floor space. This can be achieved by:
Increasing test throughput.
Minimizing changeover time needed to accommodate different package types or input media.
Minimizing downtime caused by jams or breakdowns.
Combining several functions within one handler, such as lead inspection, marking and programming of devices.
Minimizing the footprint by innovative mechanical design.
You can improve test throughput by increasing the speed at which the handler can move devices and by testing several devices simultaneously. “For devices with short test times, this means that the handler index time (time from the end of a test to the start of the next test) and total cycle time (time to process one device) must be reduced so the handler and tester are operating at optimum efficiency with minimum idle time on either,” said Kevin Brennen, Product Manager at Daymarc.
“Devices with longer test times require multisite testing to increase the number of devices processed each hour. Single-site handlers sit idle while waiting for long tests to complete. The handler must provide a test-site configuration which balances the time to bin the tested devices against the test time,” concluded Mr. Brennen.
Minimizing handler changeover time is particularly important if you test small to medium quantities of devices having a variety of package types. But minimizing downtime caused by jams or equipment breakdown is important to everyone using a handler.
A great deal of ingenuity has gone into designing handlers that are flexible and reliable for a variety of package types. The comparison charts that accompany this article show that some handlers accept more than a dozen package types, including those that come in many different sizes. More than 100 conversion kits are available for some handlers.
Installing a changeover kit may range from 2 minutes to an hour, depending on the basic design and differences in device packages. Generally, pick-and-place handlers accommodate a greater variety of devices with less changeover time than gravity-fed handlers, but they usually have a higher index time.
Although more and more SMT packages are being used, with TSOP the most popular, older packages are not disappearing. Some companies provide dedicated handlers accommodating just the older or specific-purpose package types.
Dedicated handlers are often less expensive and require no changeover time. “Contrel delivers handlers to a market for high-voltage testing of devices in DIP and TO220/TO218 packages,” said Judi Boissicat at Contrel Corp. “The demand for inexpensive DIP handlers that are rugged and reliable is still high and expected to remain so for several years.”
Optical Associates Inc. (OAI) is also one of the few companies that has a TO package solution, according to Mike Gillette, Director of Sales. But OAI, in step with the majority of handler companies today, provides multipurpose gravity-fed as well as pick-and-place handlers to accommodate practically every package.
But regardless of package type, downtime can be very much a function of the promptness and quality of support provided by the supplier. “Customer requirements for service excellence continue to intensify throughout the world,” said David Senum, Director of Product Marketing at Aetrium. “Service 24 hours a day, 7 days a week will become the norm for the industry as pressure to decrease equipment maintenance cost and downtime continues.”
Bob Williams, Sales Manager at Delta Design, concurred: “The global nature of the IC test industry, particularly the rapid growth of the Southeast Asia market, requires suppliers to provide superior, consistent and timely technical support to customers regardless of their location,” he said.
As for the future, more companies will follow the lead of Exatron, Data I/O, Robotronics and Aseco and combine several functions within one handler or provide modular, multipurpose handlers such as those from Aetrium and Delta Design. Many handlers will provide parallel test sites, and capabilities for accommodating 16 or 32 devices will no longer be unique.
Handlers will continue to keep up with SMT, fine-pitch lead, ball-grid array and other popular packaging trends. Pick-and-place handlers that transport fragile devices in carriers will become more widespread. For example, the MCT 6100 uses carriers that handle and test bare die.
The handler industry will continue to change and cope with the challenges posed by the semiconductor industry (see sidebar). To provide you with an overview of currently available handlers—both gravity-fed and pick-and-place—we have compiled comparison charts which highlight their basic capabilities. For detailed information, please circle the corresponding number on the EE Reader Service Card.
Sidebar
Back End in Motion
The seemingly staid and normally unexciting back end of the semiconductor manufacturing process—beginning with wafer probe and ending with product shipment—has undergone substantial change with the emergence of surface-mount devices (SMD). In no area is this statement more provable than in the IC test-handler segment.
Prior to SMD, suppliers of through-hole package handlers were primarily small, privately held engineering firms—generally under-capitalized and offering a limited product mix to a concentrated but loyal customer base. Their core technologies consisted of specific thermal conditioning capabilities combined with relatively simple contactor designs, primarily using gravity to advance the individual IC packages through the test handler.
IC test-handler designs became increasingly more complex as SMD came into prominence over the last decade. An abundance of new packages required revolutionary designs. Often, they needed technology not previously used by IC handler suppliers, such as pick-and-place handling techniques, new materials and thermal-chamber designs.
SMD performance was so enhanced that totally new higher-performance contactor designs were required. SMD meant re-engineering the entire handler company.
The individual supplier’s ability or willingness to adapt is the most singular event in forming today’s IC test-handler supplier hierarchy. These companies are generally larger, more adequately capitalized and more likely to be publicly owned. They offer a broader product mix comprised of more complex technology, and deal with a larger and more discriminating customer base than their predecessors.
IC test handling has become what may be the most rapidly changing market segment. Just a few years ago, privately owned companies, such as MCT, SymTek, Daymarc, Multitest and Delta Design, dominated the market during the days of through-hole packages. While these companies were quite successful, in some cases their lack of sufficient capital prevented them from adapting to the changing demands of customers.
The fortunes of all these companies changed more when they were joined by start-up companies, such as Aseco and Aetrium, who were well-capitalized by venture capital firms and specifically formed to supply IC test handlers for the emerging SMD market. The broader, more diversified SMD market demanded that IC test-handler suppliers expend capital on new designs, and not all suppliers were up to those demands.
While all these names are still active in the market, the financial structure of some has severely limited their capability to compete for market leadership. Some of these companies have changed their marketing thrust or core technologies with great success.
Delta Design, now the dominant domestic IC test-handler supplier of pick-and-place IC test handlers, is a notable example of the capability to adapt to a changing market. Another is Aetrium’s new Versatus™ generic IC handling modules marketed to manufacturers of back-end equipment such as lead scanners, markers and lead reformers. Others, however, have not been as fortunate.
While this is a very forgiving market, it is not for the weak of heart. It is one of the most competitive, if not the most entertaining, segments of the industry. In the last 18 months alone, these transactions took place:
Aseco, Aetrium and MCT all became public companies in 1993 and all tried to acquire SymTek. Aetrium succeeded in acquiring SymTek’s assets from bankruptcy court in 1994.
Daymarc was acquired by Cohu in mid 1994.
MCT sold a tester product line to Megatest in late 1994.
The result of all these transactions is a smaller but stronger supplier base—a net gain for the industry. The ongoing work in synthesizing these mergers certainly is far from over and allows no time for complacency.
According to VLSI Research Inc., the IC test-handler segment is projected to grow at 17% a year through 1997. The next few years seem especially bright. As semiconductors continue to grow in volume and varieties of packages, the handler market is now being serviced by fewer—but generally larger and better financed—companies, which bodes well for all at the back end.
Joseph C. Levesque
CEO and President
Aetrium, Inc.
Copyright 1995 Nelson Publishing Inc.
May 1995
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