Temperature & Humidity Accelerated Life Testing

Peck’s Relationship for Temperature & Humidity Testing

High temperature & humidity is a common test condition. For specific failure mechanisms there are models available (or you can create a model) to determine the translation from test to use conditions.

These acceleration models generally only apply to one specific failure mechanisms and do not apply to a system level estimate of life. If the failure mechanism is the dominate failure mechanism for the product, then an ALT exploring just that mechanisms would provide a life estimate.

Peck’s relationship is an acceleration model for effect of humidity on the metallization elements of integrated circuits within plastic enclosures (typically an epoxy over molding).

Peck’s Relationship for Temperature & Humidity

When electronic components moved from small metal cans to epoxy packaging, one of the issues was moisture ingress leading to the silicon device failing quickly. If the epoxy over-molding did not form an adequate seal the application of a relatively high humidity at an elevated temperature could determine if the package would survive nominal temperature and humidity conditions for an extended time.

Peck and colleagues gathered reports and studies of the effects of temperature and humidity on the time to failure behavior for a range of epoxy based packages. The model they developed is…