Humidity Robustness and Risk Assessment for PCBAs and Power Electronics
Manufacturer-independent root cause analysis and risk assessment for moisture-related failures, SIR anomalies, or qualification issues (in accordance with IEC 60068-2 / IPC-TM-650). We objectively assess failure paths and derive robust measures for development, PPAP, and production release.
Humidity robustness Why Humidity-Related Failures Are Rarely Accidental
Humidity alone rarely causes electronic assemblies to fail. The actual risk typically results from the interaction of several factors within the electronic system:
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Environment & climatic stress: Condensation, high relative humidity, temperature cycling and changing climatic conditions.
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Surface cleanliness: Ionic contamination, such as flux residues, as well as conductive particles according to VDA 19, can promote leakage currents, corrosion and electrochemical migration.
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Design & protection: Critical geometries, small conductor spacing, insufficient edge coverage of conformal coatings according to IPC-CC-830, and high electric field strengths can significantly increase the risk of humidity-related failure mechanisms.
The challenge: Humidity-related failures are often intermittent. They may occur during climatic testing or under specific environmental conditions, disappear again once the assembly is dry, and therefore remain difficult to reproduce and localize.
Have your humidity risk assessed
Confidential and structured. With NDA on request.
Typical faults & failure mechanismsWhat Typically Happens in Moisture-Related Failures
Moisture failures often do not manifest themselves as an immediate total failure, but as intermittent faults that occur under certain climatic and load conditions and disappear again during normal operation.
Typical problems in the field:
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Faults occur depending on the weather, storage or transportation conditions
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Anomalies intensify under climatic conditions and electrical load
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Symptoms range from functional drift to dropouts or short-circuit events
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Visible indications are possible (deposits, traces of corrosion, dendritic structures, particles), but not necessarily present
Examples of possible causes of failure and failure mechanisms
Moisture-related failures can cause very different types of damage. Correct classification is crucial because the boundary conditions and failure paths differ significantly depending on the cause.
1 | Electrochemical Migration (ECM)
Dendrites can form conductive bridges on the PBA surface and trigger short circuits, especially in the event of condensation.
Typical failure: intermittent short circuit or sharp drop in insulation resistance when exposed to moisture.
2 | Anodic Migration Phenomenon (AMP)
Conductive paths between layers as a result of Electrochemical Migration, favored by a weakened layer bond.
Typical failure: breakdown or increase in leakage current in the laminate.
3 | Water Treeing
Combination of AMP-like degradation in the layer composite and local discharges in micro-gaps and pores under moisture stress.
Typical failure: gradual deterioration of the insulation with increasing leakage currents.
4 | Insertion Loss
Moisture or particles can influence the insulation resistance at switching frequencies typically from 100 kHz and attenuate the signal transmission.
Typical failure: Functional drift or conspicuous changes in the signal parameters without a classic short circuit.
5 | Parasitic Leakage Current
Moisture on and in polymeric protection systems can favor conductive paths, especially at temperatures typically above 120°C.
Typical failure: Increase in leakage current up to protective shutdown or sporadic malfunctions.
6 | Thermal Event
Conductive particles can trigger short circuits and cause consequential thermal damage.
Typical failure: abrupt short-circuit event with localized melting or fire.
From classification to reliable root cause analysis
On the basis of over 800 processed cases, we create a comprehensible risk, damage and root cause analysis. The aim is a reliable classification that brings together the boundary conditions, failure paths and risk drivers in the system context.
Our support: your measurable benefitHow we provide support for moisture failures and moisture risks
Moisture-related failures are often addressed too late in day-to-day operations, because they are difficult to reproduce and diagnose. We provide targeted support at the process points where causes are narrowed down, risks are assessed and decisions are made for testing, design, process and protection concepts.
An Overview of Your Benefits
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Objective risk assessment: Identify weaknesses in layout, material combinations and protection systems (coating/potting) at an early stage and validate them using standards-based test methods, such as IPC-CC-830, the ZVEI guideline and IEC 60068-2.
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Cost and test optimization: Avoid repeated DV/PV qualification loops, focus test scopes on the relevant risks, and reduce scrap, rework and field-related costs.
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Measurable results: Early identification of weaknesses and targeted validation of process windows help safeguard delivery capability and sustainably reduce the risk of customer complaints.
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Launch assurance and PPAP: Define robust specification and validation criteria for production release to support a reliable series ramp-up.
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Efficient failure analysis: Systematically assess complex failure mechanisms such as ECM, leakage currents and corrosion, clearly verify their causes and reduce the risk of subsequent field failures.
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Faster 8D processing: Systematically determine the Cause and Root Cause as a sound basis for customer complaints, 8D reports and technical customer communication.
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Targeted design optimization: Derive actionable requirements for creepage and clearance distances according to IEC 60664-1, layout adjustments and coating specifications for direct implementation in development.
Measurable results: Early identification of weaknesses and targeted validation of process windows help safeguard delivery capability and sustainably reduce the risk of customer complaints.
Contact usEnsure Humidity Robustness or Assess a Failure Case
Whether you are facing a qualification failure during climatic testing, preparing for the PPAP process, or need to assess condensation resistance, our experts evaluate your specific case confidentially, with an NDA if required. You receive manufacturer-independent, technically sound recommendations that can be implemented directly.
ServicesSupport as required
Depending on the initial situation, we provide support with suitable formats from the initial classification to implementation in the production environment.
