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INSPECTION, MEASUREMENT, AND TEST

INSPECTION, MEASUREMENT, AND TEST 19.33

perception within that market. A manufacturer with the highest quality philosophy wants to test
every parameter possible in the best possible way. Examples of this would be high-end, expensive,
mission-critical and leading-edge technology markets. Other manufacturers want to be perceived as
technology market leaders. They have a dedication to quality and lead in technology but in less “mis-
sion critical” markets. Others promise a fast turnaround, taking proven technology and being a sec-
ond source or improving on it in other ways.
Lastly, there are those who deal in largely commodity chip markets where the profit margins are
thin and COT is a key consideration. An example of this is devices used in the consumer market,
such as DVD players.

What Is the IC Manufacturing Company’s Product Line Emphasis? The emphasis of an IC man-
ufacturer’s product line usually aligns with the test philosophy as a rule of thumb. If the product line
focuses on R&D technology, either through the IC process or design functionality and performance-
pushing technology, then rigorous testing will be required. If a product line is market focused and
has a goal of delivering the right device at the right time then a mixture of performance innovation
and COT is required. If manufacturing cost management is a product line’s focus, then COT is the
largest concern. In reality, many companies run their different product lines as a portfolio mixture of
all of these. Also, some product lines exhibit portions of each of these traits throughout their prod-
uct life cycle.
General Purpose Platform Versus a Focused Solution. Another decision to be made is a general-
purpose platform versus a more focused solution to test very specific devices. Some factors to con-
sider on picking a general-purpose platform include: Is the number of different products (product
mix) high enough that there is a benefit to a one-or two-platform strategy? The general-purpose plat-
form lifecycle may justify the investment in equipment and training, if it is long and can maintain
excellent OEE past its depreciated timeframe. Also, many vendors will field upgrade new capabili-
ties into their existing platform base and even may have features that allow “pay as needed” system
capabilities that keep the platform technology ahead of requirements.
Other factors to consider on picking a focused platform include: Will specific devices keep the
utilization high enough to justify a focused platform? A focused platform can be a good choice if the
number of products is low, but the volume of product sold is high. Linear and Flash memory market
segments are some good candidates for this.

19.3.2 Use Industry Contacts to Determine Vendors
in the Specific Market Segment of Interest
Once the needs for tests have been decided, vendor identification is next. Using industry/trade pub-
lications, professional sources, and the web to identify the leaders in the desired market segment is
a good start. Another source can be to examine what one’s competitors are using for a test solution,
or stated another way, what are the market leaders using for an IC test solution? All the normal busi-
ness checks into the history and reputation of the company should be done when considering a test
supplier.

19.3.3 Planning and Justifying the Selection Process
The decisions made as a result of understanding the need to test will determine what kind of equip-
ment is needed. Using industry contacts will determine which test vendors or equipment providers
are in that market segment. These decisions can involve large capital expenditures and significant
time for many resources within a company. This selection must be approached methodically and pro-
fessionally with a plan to justify to the management and investors that a tester is required, or that a
new tester is needed if the current platform no longer meets the needs. Technology gaps or discon-
nects, when the current solution can no longer meet the device requirements, are typically the easi-
est to justify. However, there may also be cost drivers that can justify a new test platform, such as
the need to lower COT or to retire old equipment that is no longer cost-effective. The latter may be

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