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This paper describes a joint SAE automotive and aerospace Recommended Practice SAE J3168 now in development to standardize a process for Reliability Physics Analysis. This is a science-based approach to implement Physics-of-Failure research in conducting durability simulations in a Computer Aided Engineering Environment. It is used to calculate failure mechanism susceptibilities and estimate the likelihood of failure and the expected durability life of Electrical, Electronic and Electromechanical components and equipment, due to stresses such as mechanical shock, vibration, temperature cycling, etc. Reliability Physics Analysis is based on the material science principle of stress driven damage accumulation in materials. The process enables the identification of potential failure risks early in the design phase so that such risks can be designed out in order to efficiently design high reliable and robustness into electronic products.

This paper describes a Reliability Physics Analysis process to assess aging and the potential for early wearout of microcircuits, as documented in SAE ARP6338. As microcircuit feature sizes (gate length, line width, etc.) continue to shrink to near atomic levels, they become increasingly susceptible to aging mechanisms such as Electromigration, Time-Dependent Dielectric Breakdown, Hot Carrier Injection and Bias Temperature Instability effects. These mechanisms are driven by voltage, current and thermal operating stresses resulting in shorter times for aging to progress to the point where wearout can occur. If the times to wearout are shorter than the required lifetimes of the microcircuits in their applications, the microcircuits are called Life-Limited Microcircuits. A brief overview of these aging mechanisms and their impact on the long-life electronics systems used in Aerospace, Automotive, Defense, and other High Performance industries is provided.

Integration of advanced sensing systems in autonomous vehicles is possible due to high performance processors that utilize high-density ball grid array (HD-BGA) packaging. The configuration of advanced sensors within autonomous vehicles requires the placement of processing modules within non-conventional vehicles compartments that can drastically influence the reliability of HD-BGAs. Durability of HD-BGAs to different loads depend on their location within the vehicle as well as the form factor of the package itself. Reliability Physics Approach (RPA) combines simulation tools and empirical models to predict the reliability of advanced electronic packages under complex environmental and operational loads by identifying the susceptibility of electronic components to the dominant failure mechanism.

Quality, Reliability, Durability (QRD) and Safety of vehicular Electrical/Electronics (E/E) systems traditionally have resulted from arduous rounds of Design-Built-Test-Fix (DBTF) Reliability and Durability Growth Testing. Such tests have historically required 12-16 or more weeks of Accelerated Life Testing (ALT), for each round of validation in a new product development program. Challenges have arisen from: The increasing number of E/E modules in today's vehicle places a high burden on supplier's test labs and budgets. The large size and mass of electric vehicle power modules results in a lower test acceleration factors which can extend each round of ALT to 5-6 months. Durability failures tend to occur late in life testing, resulting in the need to: perform a root cause investigation, fix the problem, build new prototype parts and then repeat the test to verify problem resolutions, which severely stress program budgets and schedules.