VIRTUAL: Design and Test of Non-Hermetic Microelectronics (3/30/2021 – 4/1/2021)


Instructors: Thomas Green and Robert Lowry

Description: Packages made from polymeric materials as opposed to traditional hermetic materials (i.e. metals, ceramics, and glasses) require a different approach from a design, production, testing, and qualification standpoint. The problem is now one of moisture diffusion through the barrier and package interfaces. Fick’s law of diffusion and the interaction of moisture and other gases with the plastic package, with or without a cavity, is of primary importance.

This course begins with a brief overview of hermetic packaging and associated testing methods that have been developed over the years, some of which are applicable to cavity style non-hermetic enclosures. Then the focus is primarily on the materials used to build non-hermetic packages and the variety of testing methods available to evaluate the non-hermetic package. A review of the techniques and methods to evaluate a “non-hermetic” approach is discussed with a special emphasis on cleaning of the device prior to encapsulation and alternate test methods to evaluate reliability. Click here to see the full outline.

The course is intended for process engineers, designers, quality engineers, and managers responsible for design, test and production of cavity and non-cavity style non-hermetic packages intended for use in high reliability military and Class 3 medical implants.

Topics include:

  • What is “hermeticity” and how to test for it (brief overview)
  • How it is different from “non-hermetic” packaging and test
  • Non-hermetic Materials and Processes
    • Fick’s law fo diffusion
    • Thin films and coatings e.g. ALD and Parylene-C
    • PEEK, LCP, Kapton, Silicones thick coatings and potting compounds
  • Importance of Surface Cleanliness
    • How to evaluate surface cleanliness
  • Coating material evaluation and effectiveness
    • Adhesion, pinholes, cracks
  • Non- Hermetic Packaging and Testing
    • WVTR,  IPC-CC-830
    • Moisture uptake (absorption) by materials TGA/TML, WVR
  • Test methods applicable to non-hermetics
    • A Critical Review of Waterproof Testing Standards IP 67/68
    • TM 5011 and NASA outgassing Specs
    • RGA for non-hermetic cavities
    • Moisture sensors
  • Qualification test methods and standards
    • Mil grade Non-hermetic qual standards…e.g. Class Y