Understanding the Corrosion Mechanisms of Electronic Devices Subjected to Very Polluted Environments

In recent years, after studying data from different parts of the world, we have arrived to the conclusion that the Atmospheric Accelerated Corrosion Test (ACT) Methodologies that have been used successfully in United States and Europe do not mimic the environment typically found in developing countries. In those countries harsher conditions (higher temperatures and relative humidity plus increasingly high concentration of pollutants and particles), can lead to accelerated corrosion of must metals, devices and electronic equipment. In order to understand the effect of aggressive environmental conditions (in more polluted parts of the world) on electronic devices it is important to understand their effect on pure metals (for example, to understand the different corrosion layers in Cu) and then move to more complicated systems. Additionally, it is important to understand the correct acceleration factors for any ACT.

This work will show some of the environmental work pertaining to atmospheric corrosion induced by an aggressive environment, particularly when comparing available data from USA with available data from developing countries. By duplicating the corrosive environment from those countries and knowing that the correct failures modes are initiated in the electronic devices, it is possible to obtain a meaningful accelerated corrosion test that can mimic the real environment. This paper will also try to show some of the ACT results on copper and steel coupons exposed to harsh environments as well as their surface characterization.

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