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First of all, TriQuint GaAs reliability is good relative to the corporate goal, which is to have failure rates less than 100 FIT for the first 20 years of life at 150°C. For reference, twenty years is 175,320 hours. Each integrated circuit design has its own unique failure rate which remains low over its useful lifetime, increases at wear out, and then decreases afterward. Empirical data indicates that TriQuint ICs have median lives exceeding 1 million hours (114 years). This data is collected by conducting life tests at temperatures between 225° and 275°C.

There is not a single FIT number that is representative for all ICs manufactured at TriQuint. However, many semiconductor companies do quote a particular number which they feel is representative of the expected failure rate for their devices. It is only possible to calculate a representative number if one assumes that all devices fail because of the same failure mechanism and the failure rates of the mechanism is constant. To provide a similar number for comparison, a calculation was made which assumes a common failure mechanism, a constant failure rate, and uses data gathered on several life tests. To determine the rate with a confidence level, the "Chi-Square" distribution with a 60% confidence level was used. The resulting answer depends heavily on the temperature expected for actual use and the activation energy of the failure mechanism. For temperatures below the highest specified temperature of operation (150°C) and the most pessimistic activation energies (above 0.3eV), the failure rates for TriQuint devices should be less than 121 FIT.

Admittedly, this calculation is based upon an incorrect assumption, and it is provided here only for comparison purposes since many other semiconductor manufacturers provide data only in this form. Failure rates would be expected to be much lower early in life and exceed this estimate at wear out.