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here are a lot of Test Engineers working in electronics or in semiconductor technology companies. But did you ask your self who you really are? In what way you can contribute to your organization?

Perhaps this would be a good time to discuss the traditional roles of test engineers. But before jumping into that perspective lets take a classical scenario during new product introduction(NPI) phase to understand better the whole process.

A new semiconductor product typically begins in one of two ways. Either a customer requests a particular type of product to fill a specific requirement, or a marketing organization realizes an opportunity to produce a product that the market needs. In either case, systems engineers help define the technical requirements of the new product so that it will operate correctly in the end-equipment applications. The systems engineers are responsible for defining and documenting the customer's requirements so that the rest of the engineering team can design the product and successfully release it to production.

After the systems engineers have defines the product's technical requirements, design engineers develop the corresponding integrated circuit. Hopefully, the new design meets the technical requirements of the customer's application. Unfortunately, integrated circuits sometimes fail to meet the customer's needs. The failure maybe due to a fabrication defect or it may be due to a flaw or weakness in the circuit's design. These failures must be detected before the product is shipped to the customer.

The Test Engineer's role is to generate hardware and software that will be used by automated test equipment (ATE) to guarantee the performance of each device after it is fabricated. The test software (usually called test program) directs the ATE tester to apply a variety of electrical stimuli (such as digital signals and sine waves) to the device under test (DUT). The ATE tester then observes the DUT's response to the various test stimuli to determine whether the device is good or bad.

Sometimes the test engineer is also responsible for developing hardwareand software that modifies the structure of the semiconductor die to adjust parameters like DC offset and AC gain, or to compensate for grotesque manufacturing defects. Despite claims that production testing adds no value, this is one way in which the testing process can actually enhance the quality of the individual ICs. Circuit modifications can be made in a number of ways, including laser trimming, fuse blowing and writing to non-volatile memory(NVM) cells.

The test engineer is also reponsible for reducing the cost of testing through test time reductions and other cost-savings measures. The test cost reduction responsibility is shared with the product engineer. The product engineer's primary role is to support the production of the new device as it matures and proceeds to profitable volume production. The product engineer helps identify and correct process defects, design defects and tester hardware/software defects.

Sometimes the product engineering function is combined with the test engineering function, forming a single test/product engineering position. The advantage of the combined job function is that the product engineering portion of the job can be performed with a much more thorough understading of the device and test program details. The disadvantage is that the product engineering responsibilities may interfere with the ability of the engineer to become an expert on the use of the complex test equipment. The choice of combined versus divided job functions is highly dependent on the needs of each organization.