What is Electrochemical Migration (ECM)?
Electrochemical migration (ECM) refers to the phenomenon where metal ions migrate under the influence of an electric field, leading to the formation of conductive paths between conductive elements. Electrochemical migration (ECM) can result in the growth of a metal deposit from cathode to anode. It could happen on both the surface and inside of Printed Circuit Boards. This can be hugely problematic & can cause short circuits leading to intermittent or complete failure of electronic devices.
Watch the Video below which explains the phenomenon.
Evaluation of Insulation Resistance (IR)
Insulation resistance is a measure of how well insulating materials resist the flow of electrical current. The analysis of IR involves applying a voltage across the insulation and measuring the resulting current to ensure effective isolation between conductive elements. In the context of electronic devices and PCBs, maintaining a high insulation resistance is essential to prevent unintended leakage of electrical current and to ensure proper isolation between conductive elements. Low insulation resistance can lead to short circuits, malfunctions, and reliability issues.
Therefore, in the quest for robust electronic reliability and as electronic devices become smaller and denser, Electrochemical Migration (ECM) analysis and Insulation Resistance (IR) evaluation becomes increasingly crucial for both the semiconductor manufacturers and the PCB assembly manufacturers.
Also, as the demand for millimeter-wave (mmWave) 5G technology rises, there is an anticipated rapid growth in the use of low-loss materials. These materials are expected to play an increasingly important role in the development and deployment of 5G technology. Ensuring the reliability and performance of components using these materials requires tailored testing procedures and equipment to address the unique challenges associated with their use in high-frequency and high-speed applications.
The ESPEC Electrochemical Migration Evaluation System
In response to these trends, ESPEC, aims to support its customers by providing products that improve the efficiency of insulation reliability evaluations and dielectric constant measurements. The Espec Electrochemical Migration Evaluation System (AMI System) allows these evaluations to be performed continuously with a high degree of accuracy.
The ESPEC AMI system, integrates ECM and IR evaluations, assessing both the potential for conductive path formation and the resistance capabilities of insulating materials. The goal is to simulate and study the conditions under which migration might occur and evaluate the materials and design of electronic components to ensure their reliability over time.
Assessment using the AMI system involves subjecting the specimens to controlled environmental conditions, such as elevated temperature, humidity, and electrical biasing using up to four environmental test chambers. The connected AMI system monitors the development of conductive paths and assesses the potential for electrochemical migration. Voltage is applied under high temperature and humidity conditions to test the current leakage caused by insulation breakdown.
AMI captures both gradual changes in resistance and unexpected instantaneous rapid drops. This testing capability spans a wide voltage range, allowing evaluations across diverse applications — from low-voltage scenarios like mobile devices to high-voltage on-board devices. ESPEC provides a versatile lineup of specifications tailored to meet the unique requirements of each application and purpose. This includes a 100 V constant stress voltage, and optional 300 V and 500 V voltage specifications. For specialized needs, custom products can be tailored with higher voltage specifications, such as 1000 V and 2500 V.
The evaluation process helps electronics manufacturers identify potential issues early in the design or production phase, allowing them to make necessary adjustments to improve the reliability and longevity of electronic devices.
Test Set Up With An Environmental Test Chamber
The AMI System can be used for multiple evaluation tests:
- Insulation Resistance Evaluation Test:
Measures the resistance of the insulating material to electrical current, helping to ensure that the insulation remains effective in preventing unintended leakage of electrical current.
- TDDB Evaluation Test :
A Time-Dependent Dielectric Breakdown evaluation test is a method used to assess the long-term reliability of insulating materials. This test helps predict the lifespan and performance of insulating layers within integrated circuits.
- Reverse Bias Test:
Assess a device’s performance and characteristics when operated in reverse bias conditions.
- Leakage Current Measurement Evaluation Test:
Measuring the amount of unintended or leakage current flowing through an insulating material or device.
Benefits of Integrated ECM & IR Analysis with ESPEC AMI System:
- Early Identification of Vulnerabilities: By simultaneously evaluating ECM and IR, the AMI system allows for the early identification of vulnerabilities in both conductive paths and insulating materials, providing a more comprehensive understanding of potential failure points.
- Synergistic Problem Solving: ECM and IR issues are often interconnected. For instance, the migration of metal ions due to ECM can compromise insulation, leading to decreased insulation resistance. The integrated AMI approach enables a synergistic understanding of these issues for more effective problem-solving.
- Precise Measurement for Both Aspects: The high-accuracy measurement capabilities of the AMI system ensure that subtle changes in both electrochemical migration and insulation resistance are detected, allowing for precise assessments and targeted improvements.
- Environmental Simulation: The AMI system can be connected to up to 4 environmental test chambers simultaneously and is compatible with ESPEC HAST, Platinous J, AR Series and benchtop chambers allowing for the simulation of diverse operating conditions, mimicking real-world scenarios where both ECM and IR issues may manifest.
- Versatility in Voltage Testing: The AMI system is ideal for a wide range of applications, ranging from low voltage testing to high voltage testing.
- Easy Connection: ESPEC provides not only evaluation equipment, but also a variety of compatible jigs. Our connecting jibs are customised to best suit your specimen, facilitating seamless and efficient testing by enabling easy connection of specimens and cables.
For the full technical specifications and details download the AMI brochures.