Autoclave testing evaluates the moisture resistance for non-hermetic packaging of solid-state devices. Also referred to as “steam-bomb,” the IC autoclave test is a highly accelerated test performed in a moisture-condensing or moisture-saturated environment and the moisture sensitivity levels are measured. During autoclave testing, the conditions of high temperature, pressure, and 100% humidity accelerate moisture penetration into the encapsulation of active device packages.
Moisture generally penetrates in two areas:
1) directly through the encapsulant material
2) at the sealing interfaces where the conductors (lead-frame parts) pass through the encapsulant material into the active device region.
IC Autoclave testing should be performed for new non-hermetic package introduction or whenever a package is redesigned (requiring modifications such as a change in molding compound, lead frame, die-attach adhesive, or die passivation). Autoclave testing is a special form of temperature humidity testing; it differs primarily in the fact that the IC autoclave test has a condensing ambient while HAST (Highly Accelerated Stress Test) and typical temperature-humidity testing are non-condensing. The autoclave test is typically run at 121°C for 96-hours in a pressure vessel containing a small quantity of DI or distilled water; this produces 100% humidity at a pressure of two atmospheres.
Test Specifications / Standards