Moisture Management
Hygroscopic materials in printed circuit board assembly face degradation during reflow soldering due to the rapid expansion of trapped water vapor. ipc j-std-033 establishes specific handling, packing, and shipping protocols for moisture sensitive devices to prevent delamination and internal cracking during exposure to high assembly temperatures.
Baking Methodology
Removal of absorbed moisture involves heating components in an oven environment to facilitate the diffusion of water vapor out of the package body. Duration and temperature parameters depend on the moisture sensitivity level of the device and the thickness of the component body, ensuring the internal pressure remains below the critical threshold for structural failure during subsequent thermal processing. Dry storage in desiccated cabinets or moisture barrier bags provides a secondary control layer by limiting exposure time on the production floor, a practice quantified by the remaining floor life of the component which resets after proper desiccation.
Operational Exposure
Exceeding defined floor life limits requires the intervention of a dry bake process to restore the component to a usable state. Failure to adhere to these exposure constraints results in catastrophic package damage and latent reliability issues within the solder joints. The standard governs the entire lifecycle of a component from initial seal at the supplier facility to the final placement on the circuit board.
