Therefore, components' exposure time has to be rigorously controlled according to the demands of MSLs and records carefully kept of every production run to ensure the total floor life hasn't been used up. After bake, must be reflowed within the time limit specified on the label. The following table indicates floor life of MSDs corresponding to their MSLs.įloor life at factory ambient (≤30☌/60% RH) MSDs differ from each other based on different Moisture Sensitive Levels (MSLs) ranging from Level 1 through Level 6. The minimum shelf life of a standard MSD is at least 12 months from its seal date. Then bag seal date printed on caution or bar code label should be checked in order to simply figure out the remaining shelf life of the MSDs packed inside MBBs. If holes are unfortunately found on MBBs with inner components exposed and HIC showcases an exceeded data, baking should be undertaken on parts before their genuine applications. All these defects will possibly lead components or inner layers of MBBs exposed. Together with desiccant, HIC is placed inside moisture barrier bag to determine the humidity degree of MSDs inside.Īs soon as MBBs containing MSDs are received, appearance inspection should be carried out first in order to verify there are no holes, gouges, tears, punctures or openings. When the indicated RH is exceeded, corresponding dot will show a color change from blue to pink. Made from chemical products, HIC is a card applied to measure RH sensitivity degree. It is a length of time during which MSDs can be stored in sealed MBBs. It is used to pack moisture sensitive devices and stop water vapor from permeating into the bag. This term also applies to the MSD's exposure time from the opening of vacuum package to resealing.

Manufacturer stipulates the longest exposure time from baking completion to sealing package, which accounts for MET.

It indicates the longest time of MSDs exposed to factory environment (≤30☌/60%) before solder reflow with moisture barrier bag opened. A type of material capable of absorbing moisture and is applied to maintain ambient RH (relative humidity) within a relatively low range. Carrier is actually a container that holds components such as a tray, tube, or tape and reel. The information describing the product includes part number, quantity, lot information, supplier identification and moisture sensitive level (MSL). This refers to the manufacturer's label that contains information in a code composed by parallel bars with different widths and spaces. Along with the introduction and discussion on how to store and handle moisture sensitive devices, it's also important to go through the technical terms below accompanying MSDs to accurately understand the content of the remaining article.

Ipc standard for pcb baking