IPC - Association Connecting Electronics Industries
Scope
This classification procedure applies to all nonhermetic SMDs in packages@ which@ because of absorbed moisture@ could be sensitive to damage during solder reflow. The term SMD as used in this document means plastic encapsulated surface mount packages and other packages made with moisture-permeable materials. The categories are intended to be used by SMD producers to inform users (board assembly operations) of the level of moisture sensitivity of their product devices@ and by board assembly operations to ensure that proper handling precautions are applied to moisture eflow sensitive devices. If no major changes have been made to a previously qualified SMD package@ this method may be used for reclassification according to 4.3. This standard cannot address all of the possible component@ board assembly and product design combinations. However@ the standard does provide a test method and criteria for commonly used technologies. Where uncommon or specialized components or technologies are necessary@ the development should include customer/manufacturer involvement and the criteria should include an agreed definition of product acceptance. SMD packages classified to a given moisture sensitivity level by using procedures or criteria defined within any previous version of J-STD-020@ JESD22-A112 (rescinded)@ or IPC-SM-786 (rescinded) do not need to be reclassified to the current revision unless a change in classification level or a higher peak classification temperature is desired. Annex B provides an overview of major changes from Revision D to Revision E of this document. Note: If the procedures in this document are used on packaged devices that are not included in this specification's scope@ the failure criteria for such packages must be agreed upon by the device supplier and their end user. PURPOSE The purpose of this standard is to identify the classification level of nonhermetic surface mount devices (SMDs) that are sensitive to moisture-induced stress so that they can be properly packaged@ stored@ and handled to avoid damage during assembly solder reflow attachment and/or repair operations. This standard may be used to determine what classification level should be used for Surface Mount Device (SMD) package qualification. Passing the criteria in this test method is not sufficient by itself to provide assurance of long-term reliability. MSL (moisture sensitivity level) ratings generated by this document are utilized to determine the soak conditions for preconditioning as per JESD22-A113. Note: A related document@ J-STD-075 (Classification of Non-IC Electronic Components for Assembly Processes) identifies and includes PSL (process sensitive level) classification requirements for non-ICs (non-integrated circuits) in addition to referencing MSL (moisture sensitivity level) classification requirements from this document. Some ICs may be process sensitive. Please refer to J-STD-075 for potential future PSL classification requirements for ICs.