FutureProofing DDPA: Innovation Meets AS6171/4A Requirement
By Adam Hook, Senior Principal Components Quality Engineer, Harvard Bioscience
Obsolescence Management requires the implementation of a counterfeit mitigation strategy, as obsolete components are prime targets for counterfeiters. AS6171/4A mandates Delid/Decapsulation Physical Analysis (DDPA) for all Moderate, High, and Critical Risk components in aerospace devices.
Adam Hook
Chemical DDPA methods are preferred over laser or mechanical methods due to their lower specimen damage risk. “Laser decapsulation places the surface at risk due to ablation damage caused by the glass beads.[1]” However, existing chemical methods utilize nitric and sulfuric acid which can cause permanent respiratory damage with as little as a 5-second exposure. Decapsulation is done under a vented hood but gasses can escape. Because Continuous Emission Monitoring Systems (CEMS) cost $12,000 and $1,000 per month for monitoring fee.[2,3] most decapsulation service providers do not instantaneously monitor exposure limits defined by OSHA.
Whereas SAE Aerospace Standards regulate aerospace and defense industry, the ISO 13485 applies to medical device industry. The ISO 13485 standard defines risk as probability of occurrence of harm and the resultant severity. Both the risk of counterfeit components in the supply chain (and in your devices) and the existing methods to mitigate that risk DO NOT align with this requirement.
In 2025, a significant industry change, akin to RoHS (Restriction of Hazardous Substances), underscores the importance of considering the risks and long-term costs of regularly using carcinogenic substances. 3M’s decision to phase out PFAS (Per- and Polyfluoroalkyl Substances) within two years sends a clear message: safer chemistries are the future.
The common decapsulation chemicals have more immediate toxicity when compared to the substances removed under RoHS and PFAS regulations. Continued use of nitric and sulfuric acid will lead to heightened scrutiny, regulation, business risk, and cost. General Dynamics echoes this concern, emphasizing their commitment to worker health and safety in their 2022 Corporate Sustainability report. Examples include implementing safety standards and minimizing environmental hazards.[4]
It is important for the industry to have a non-toxic method for die decapsulation of suspected counterfeit components because traditional decapsulation methods, such as acid etching, can be harmful to the environment and human health. Additionally, non-toxic methods are essential for ensuring the safety of personnel involved in the process and for minimizing the environmental impact of the decapsulation process.
The adverse outcomes should never surpass the severity of the illness it aims to treat. Individuals seeking to harm Americans introduce fake components into our supply chain. Consequently, we address this threat by employing highly hazardous chemicals, posing a risk of enduring medical harm to those attempting to ensure our safety.
Even in the absence of imminent regulation there is an industry benefit to nontoxic decapsulation chemistry. Without the threat of toxic exposure, workers can channel their full attention to effectively and productively authenticate components at risk of being counterfeit.
Criminals will continue using techniques such as sanding, micro-blasting, acid etching, blacktopping, and remarking to counterfeit components. These methods are low cost and high return for those who employ them. Counterfeit components can also be produced and distributed in grey market by re-labelling, re-furbishing, and re-packaging devices.
The component parts market exploits buyers who lack effective counterfeit mitigation processes and urgently need specific parts. In 2022, ERAI reports that 32.5 percent of parts reported as suspect counterfeit were “obsolete” or “not for new design,” the remaining 62.2 percent were “active” parts. High demand parts regardless of their lifecycle are targeted.[5]
With the increasing advancements of counterfeiting components the electronics manufacturing industry should remain vigilant. Whether we choose to non-toxically authenticate components because of satisfying regulation requirements, health and safety benefits, cost to authenticate, or quality of the reports themselves; everyone in the electronics industry gains with the industry shift towards non-toxic decapsulation authentication.
NOTE: Adam will be presenting material from this work at SMTA’s Upper Midwest Expo June 3-4, 2024
[1] https://www.ultratecusa.com/wp-content/uploads/2020/07/Colvin-endpoint-final-Paper_31935.pdf
[2] https://escspectrum.com/continuous-emission-monitoring-system-upgrade-or-replace/
[4] https://www.gd.com/-/media/GD-Corporate/Responsibility/gd-2022-corporate-sustainability-report.ashx
