Calculated Steam Expansion Pressures in Reflowed Plastic Integrated Circuits
Calculated steam expansion pressures in reflowed plastic integrated circuits reach 4.69 MPa at 260°C, causing catastrophic delamination if moisture exceeds critical levels.
Desiccant Dry Bag
Moisture Barrier
Environmental barrier systems protect moisture sensitive components from ambient humidity during transport and storage. A desiccant dry bag consists of a puncture resistant laminate that limits the moisture vapor transmission rate into the enclosure. Inside the sealed environment, a porous pouch containing silica gel or clay captures any residual water molecules.
Multi layer films incorporate aluminum foil to create a physical block against gas molecules. The outer layer provides strength against tearing while the inner layer allows for a hermetic heat seal. These containers keep the relative humidity below 10 percent to prevent moisture absorption by plastic packages.
Storage Stability
Performance of the system relies on the integrity of the heat seal and the capacity of the adsorbent material. The desiccant dry bag maintains a safe environment for integrated circuits classified by jedec standards. If the vacuum seal fails, the clay quickly reaches capacity and the internal humidity rises to match the outside air.
Handling Protocol
Verification of the humidity indicator card occurs before components are removed for assembly. An expired desiccant dry bag requires the components to undergo a bake cycle to remove absorbed water. Resealing must happen within a short time window to protect the remaining stock.