As reported by SCHOTT in their article “When is Hermetic Really Hermetic?”, even small amounts of moisture inside electronic enclosures can lead to severe performance issues, including corrosion, electrical leakage, and even total system failure. This is why truly hermetic packaging—made exclusively from glass, metal, or ceramics—is essential for ensuring long-term reliability. These materials have near-zero permeability and can maintain moisture levels below 5000 PPM for decades.
The industry standard for determining hermeticity is the MIL-STD-883 Test Method 1014, originally developed for military and aerospace applications but now widely used in automotive, medical, and industrial electronics. The fine leak test, using helium as a tracer gas, is the most common method for assessing a package’s airtightness. However, without proper testing procedures, false negatives can occur, making additional tests, like the bubble or gross leak test, necessary.
A key distinction must be made between hermetic and so-called “near-hermetic” packaging. When polymers, epoxies, or plastics such as Liquid Crystal Polymer (LCP) are used, the package is considered non-hermetic. These materials have high moisture permeability and degrade over time, allowing moisture infiltration that can lead to system failure, especially in high-temperature or high-pressure environments. In contrast, true hermetic packaging enhances longevity, reliability in harsh environments, and overall performance.
Click here to learn more about Hermetic Seal Technology’s products and services.
Article with all rights reserved, courtesy of SCHOTT.