At NXP, our focus is on the quality of our product as well as its reliability related to the intended application. This application is characterized by a mission profile, which is a collection of relevant environmental and functional loads that a product is exposed to during its full life cycle when used in specific environments over time.

To guarantee product’s reliability capability we:

  1. Select and assess applicable application mission profile (speed, power, temperature, field lifetime, duty cycle, etc.)
  2. Use Built-in reliability to ensure robustness against identified failure mechanisms
  3. Assess test conditions and duration that simulate and accelerate environmental conditions and loading to which the product is exposed
  4. Define a product qualification plan and ensure compliance with Industry Standards, like JEDEC (Joint Electron Devices Engineering Council), market specific requirements like AEC (Automotive Electronic Council), for automotive, or customer specifications upon request

Semiconductor failure rates (as described in the standards above) follow a bathtub curve. There is an initial decreasing failure rate followed by a long, low-level failure rate and then eventual wear out.

For each part of the bathtub curve, NXP has methods in place to guarantee low failure rates:

  • Test and Burn-in are used to screen for early product failures (called infant mortality). This reduces the early failure rate
  • Robustness during useful life is obtained by design and checked by electrical and mechanical robustness tests like electrostatic discharging, latch-up events, soft errors and drop or shock events
  • Built-in reliability is used to delay the on-set of wear out. Extended life tests are performed for verification
Bathtub Curve: Product Failure Rates
Bathtub Curve: Product Failure Rates

Knowledge Based Qualification Methodology

A semiconductor product is an application solution (sometimes including software) for one or more use areas and consists of the following technology building blocks:

  • Wafer fabrication process for die diffusion
  • Package technology for assembly
  • Electronic design (using specific technology libraries and design flow) to provide the intended product functionality
NXP’s Reliability Knowledge Framework
NXP’s Reliability Knowledge Framework

The reliability capability of the product and its building blocks for a specific application area is demonstrated using Knowledge-Based Qualification (KBQ) Methodology, as described in JEDEC Standards JESD94, JEP122, and JEP148 and promoted by automotive industry by way of AEC-Q100/Q101 Standards, as well as the Robustness Validation Standard J1879 from SAE (Society of Automotive Engineers) and ZVEI (Zentralverband Elektrotechnik- und Elektronikindustrie). It is applicable to both new developments and changes to technology, products and manufacturing (e.g., recipe, equipment, process, materials, design/ construction).The industry uses accelerated reliability testing to simulate application life in a reasonable amount of time.

Our strategy is to determine the reliability capability by applying (where possible) the test-to-failure concept, extending reliability qualification conformance tests beyond the required levels and assessing any physical or electrical degradation of a products during those tests.

For the building blocks or complete products, the reliability capabilities are evaluated with a set of conformance tests related to specific application areas. The tests and their requirements are defined by using knowledge of potential failures modes and rules for structural similarity. These rules and tests can be used to qualify derivatives of released building blocks. For new failure modes and new or modified acceleration models or model parameters, the applicability of conformance test, requirements as well as structural similarity rules are updated.

Applicable reliability knowledge, data, tools, and methods are accessible through the NXP’s Reliability Knowledge Framework (RKF).