Overview
IEC 60749-6:2017 is an international standard published by the International Electrotechnical Commission (IEC) that defines mechanical and climatic test methods for semiconductor devices, specifically focusing on storage at high temperature. This standard evaluates the impact of prolonged storage under elevated temperature conditions on solid-state electronic devices without applying electrical stress. It is primarily utilized to assess thermally activated failure mechanisms and estimate the time-to-failure for devices including non-volatile memory devices with data retention concerns.
This edition introduces additional test conditions and clarifies the applicability of such tests, reinforcing its role in device qualification. While the test is considered non-destructive, it is highly indicative of the device’s reliability when exposed to extreme storage environments.
Key Topics
- Test Purpose: Determines the effects of time and elevated temperature on semiconductor devices during storage, focusing on thermally activated failure mechanisms.
- Applicable Devices: All solid-state electronic devices, including non-volatile memory devices prone to data-retention failure.
- Test Conditions: Devices are stored at temperatures ranging from 125°C to 300°C, as specified in the standard’s Table 1, under controlled environments.
- Arrhenius Equation: Utilizes this model to accelerate aging and failure analysis by simulating higher temperatures for estimation of lifespan under normal conditions.
- Test Procedure:
- Continuous storage at designated temperatures for specified durations, typically 1000 hours for qualification.
- Interim electrical measurements are optional but can be included for monitoring.
- Final electrical measurements must be conducted within 168 hours post-test, including parametric and functional checks.
- Failure Criteria:
- Exceeding parametric limits.
- Failure to maintain functionality under nominal and worst-case conditions.
- Data retention degradation in non-volatile memories verified through specific data patterns.
- Mechanical damages such as package cracking.
- Cosmetic defects or lead finish degradation are not classified as failures.
- Test Equipment: Requires controlled temperature chambers capable of maintaining precise temperature tolerances and electrical testing apparatus for device verification.
Applications
IEC 60749-6:2017 is crucial for semiconductor manufacturers, quality engineers, and reliability specialists who seek to:
- Qualify Semiconductor Devices: Ensure devices withstand prolonged high-temperature storage without degradation of electrical or mechanical performance.
- Assess Reliability: Gauge long-term data retention reliability especially for memory devices under thermal stress.
- Accelerate Life Testing: Use increased temperatures to model and predict device behavior over time in real-world storage conditions.
- Risk Mitigation: Evaluate the risk of thermal-induced failures to improve product design, packaging, and material choices.
- Supply Chain Assurance: Confirm device stability from production through delivery and storage phases by simulating storage conditions.
- Compliance & Standards Alignment: Align test practices with IEC’s global recommendations to meet international market requirements.
Related Standards
- IEC 60749-43: Guidelines for IC reliability qualification plans, which offers methods for selecting test temperatures and durations based on Arrhenius acceleration models.
- IEC 60749-20: Addresses resistance of plastic encapsulated surface-mounted devices to moisture and soldering heat, relevant for assessing packaging robustness.
- General IEC 60749 Series: Other parts provide complementary mechanical and climatic tests critical for holistic semiconductor qualification and reliability assessment.
This standard supports effective device qualification, reliability engineering, and thermal stress testing, promoting consistent quality and durability in semiconductor technologies worldwide. For more details and access, refer to the official IEC website at www.iec.ch.