PCBA Materials for Harsh Environments, Phase 2

Thursday, May 13, 2021
Section: Board Assembly

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Project Leaders

Jim Gryga, Foresite
Project Co-Leader

Dr. Helmut Schweigart, Zestron
Project Co-Leader

Call-for-Participation Webinar

Presentation (September 6, 2018)

Statement of Work & Project Statement

Statement of Work (Version 12.1; July 13, 2018)
Project Statement (Version 1.2; July 16, 2018)

Project Update (October 2022)

The project is developing a common test vehicle to accurately reflect typical DUT (device under test) modules, and to validate or develop pass/fail criteria.

They have decided that thermal cycling and/or thermal shock will likely be the best choice for developing early indicators of the robustness of materials and components used. To this end they have coordinated the build of a set of BGA test boards with a variety of solder paste formulations, which are now in parallel thermal cycling and thermal shock testing to compare methodologies and results.

The other branch of the project plan is the development of a common test vehicle. The team has decided to pursue the Foresite Umpire 41® PCBA design as a probable candidate as it has a variety of components and functional circuits that can be powered and actively monitored during environmental testing. Thirty-two pilot-level boards have been assembled, and a monitoring system and software have been developed and built. The system and boards are currently undergoing proof-of-concept testing in both ambient and elevated temperature and humidity environments. Early results show the ability to actively detect changes in circuit outputs, with more extensive testing and analysis planned.

Background

The iNEMI Roadmap and Technical Plan emphasize the need for extreme reliability requirements in electronics to meet warranty requirements and mission critical applications. This is especially true for electronic assemblies operating in harsh environments, including high and low extremes of temperature and humidity coupled with vibration.

When new materials are considered, the material suppliers must be able to test those materials against a set of standards and established tests. However, most standards are not written specifically for harsh environment applications, and OEMs often define their own specifications for PCB assemblies.

The purpose of this project is to build on the suite of test procedures proposed in Phase 1 by designing a common test vehicle(s) and demonstrating that the test vehicle, in conjunction with the suite of agreed tests, successfully provides a first-pass verification that a particular material is worthy of consideration for full OEM qualification testing.

Project Focus

Phase 1 of the project focused on automotive OEMs' specifications and requirements. The project team undertook a cross comparison and proposed a simplified sequence of test methodologies that could provide a high probability of a materials suitability for applications in harsh automotive environments.

Phase 2 of the project plans to develop a common test vehicle(s) to accurately reflect typical DUT (device under test) modules, and to validate or develop pass/fail criteria. Additionally, Phase 2 will review standards and test methodology requirements for PCBA materials in other industry sectors that also require high reliability and durability in harsh environments, such as aerospace.

Phase 2 will include:

Design of test vehicle to encompass a range of chosen assembled components together with standardized test patterns to evaluate specific test criteria.
Undertake a range of tests on PCB materials to demonstrate that the suite of test procedures and test vehicle provide fundamental evaluation of a materials suitability and durability in harsh environments.
It is anticipated that this Phase 2 project will take 18 months..

Project Benefits and Value to Industry

Enable commonality in specifying PCB and PCBA materials throughout the supply chain.
Provide better assurance for meeting reliability requirements as material choices widen and the miniaturization of PCB designs continues.
Reduce costs and associated timescales in re-qualifying products for each OEM proprietary specification.
Enable OEMs to more easily compare material datasheets from differing suppliers.