Issued Date：2023/11/21 AEC-Q100 Rev
With electric vehicles advancing, the reliability of automotive semiconductor components is more crucial than ever. Join us to check out the key highlights of the latest AEC-Q100 revision and stay ahead in automotive technology!
In recent years, new energy vehicles, including hybrid and electric cars, have rapidly gained popularity. Despite recent headwinds in the automotive market, such as Tesla’s declining financial performance and major strikes by U.S. automakers, the long-term trend of electric vehicles remains unignorable.
This trend is driven by modern consumers who no longer settle for basic vehicle functionality. They now expect advanced technologies in their vehicles, such as connectivity, autonomous driving, shared services, and electric powertrains. This has prompted automakers to respond proactively to future automotive trends and place increasing importance on automotive electronic components. These components are not only expected to meet functional safety requirements but also undergo a series of rigorous reliability tests to ensure they are free of defects or damage before installation, meeting the demands of the emerging automotive market.
So, how can the reliability of automotive electronic components be ensured? The Automotive Electronics Council (AEC) has introduced a series of six standards in recent years (see the AEC-Q family members here). In this edition of iST classroom, we will focus on the AEC-Q100 revision announced by AEC in October 2023, exploring the key differences as it transitions from Version H to Version J. We will analyze the new AEC-Q100 from three major aspects.
1. Defining Specific Processes and Packaging
Currently, most automotive semiconductor component application processes use mature processes of 28 nanometers or above, with only a few automotive chips, such as those used in ADAS (Advanced Driver Assistance Systems) applications, employing processes of 14 nanometers or below. As vehicles need to process vast amounts of data and provide feedback, traditional packaging formats like QFP (Quad Flat Package) can no longer fully meet the demands of advanced automotive chips, such as microcontrollers (MCUs) and high-performance computing (HPC) chips. Therefore, the application of packages like BGA (Ball Grid Array) and FC-BGA (Flip-Chip Ball Grid Array) has become more widespread.
However, in the previous version, AEC-Q100 REV-H, the specifications did not provide detailed guidelines for processes and specific packaging formats. In this revision J, AEC-Q100 has introduced definitions of the ESD (Electrical Static Discharge) tolerance for 28-nanometer process and RF frequency components, and FC-BGA packaging tests to ensure the reliability of these components in automotive applications.
Furthermore, to fully meet the requirements of FC-BGA products, when considering the inclusion of family products, specific attributes related to flip-chip packaging should be taken into account. It’s essential to highlight that bare die products and wafer-level chip scale packaging (WLCSP) are outside the scope of these attribute lists.
Figure 1: Representative Illustration of a Flip-Chip BGA Package.
(Source: AEC-Q100 REV. J)
2. Recommendations for Failure Analysis and Mission Profile
What should be done when abnormalities or failures occur in automotive electronic components during the AEC-Q100 verification process? Do you need to start from scratch? This has been a persistent question for many. The Version-J specification mentions that effective failure analysis can be carried out using the 8D Report (Eight Discipline Methodology, referring to JESD 671note) and establishing appropriate improvement procedures. These improvement measures should be validated and tracked for effectiveness and accuracy.
Once the defects are resolved, the next step is to ensure that automotive electronic components can operate normally under various complex and potential failure conditions and maintain product performance within the expected service life (usually 10 to 15 years). To achieve this goal, the Mission Profile flowchart (Figure 2) and the Knowledge-Based Test Methodology (KBTM) proposed in JESD 94note can be used to determine an appropriate testing plan. Communication with end users to define a suitable Mission Profile is also recommended.
Figure 2: Flow chart of reliability test criteria for new component based on mission profile requirements of intended application.
(Source: AEC-Q100 REV. J)
3. Changes in Test Items and Conditions
In this latest revision of AEC-Q100, there have been slight adjustments to the test content for PC (Precondition Test), THB (Temperature Humidity Bias Test), UHAST (Unbiased Highly Accelerated Stress Test), and SD (Solderability test). However, more significant changes in test items and conditions are as follows:
- The mandatory prerequisite for component qualification now includes whether the copper wire (Cu wire) used in automotive electronic components has obtained AEC-Q006 verification data.
- The wafer-level reliability verification item has changed NBTI (Negative Bias Temperature Instability) to BTI (Bias Temperature Instability) to encompass both NBTI and PBTI (Positive Bias Temperature Instability) for current CMOS technology.
- The number of cycles in Grade 0 of Temperature Cycling Test (TCT) has been reduced from 2000 cycles to 1500 cycles, and it now requires SAT testing (Scanning Acoustic Tomography) to confirm any delamination inside the chip after TCT (including all temperature grades).
- Power Temperature Cycling Test (PTC) is only applicable to devices with power dissipation ≥1 watt and power rise times <0.1 seconds resulting in junction temperature (Tj) changes ≥40°C are anticipated.
- For High Temperature Operating Life Test (HTOL), drift analysis of electrical parameters is required under applicable conditions. The FT test sequence defined as Room→Cold→Hot can be alternated with Room→Hot→Cold.
- Bump Shear Test (BST) item has been added for FC-BGA packaging.
- Due to the different ESD tolerance of 28-nanometer and RF chips compared to general automotive chips, changes have been made to the ESD test requirements (see Table 1 for details).
Table 1: This revision has made specific enhancements to ESD tolerance for 28-nanometer and RF chips (see blue text).