MSD control refers to the handling, packaging, transportation and use of MSD materials of different moisture grades, and the control of standard methods to avoid material moisture and reflow welding at high temperature leads to a decrease in product quality and reliability.
The control specifications of the MSD moisture sensitive device marking card for MSD moisture sensitive devices mainly include the following 19 specifications: 1. The production line operator can only unpack the MSD device packaging 10 minutes before use after receiving the PACKAGING. A, after opening the package, first check the degree of moisture displayed by the HIC card in the vacuum package, if the HIC card indicates that the humidity in the bag has reached or exceeded the humidity limit that needs to be baked, it needs to be baked according to the conditions specified in the "MSD Control Technical Specifications" or the incoming material warning sticker, and then produced after baking. B. Check whether there is desiccant in the MBB bag, if not, it is judged to be unqualified incoming material, and the "Process Abnormal List" is given written feedback to IQC processing. C, non-original manufacturer packaging or unpacking after repackaging, should check whether there is a "moisture sensitive device using the tracking card", and check whether the cumulative workshop life is less than the requirements of the device, if it is close to the failure time or "moisture sensitive device using the tracking card" filled in with abnormalities, should refuse to return the material room for baking or other processing. D, the material is sent to the production line, the production personnel found that the incoming material does not meet the MSD control specifications, should refuse to receive the production and change the material. 2. All moisture sensitive devices must be filled in immediately after unpacking the "moisture sensitive device use tracking card". 3. Be careful when unpacking, open the seal at about 1cm (use a blade to cut, strictly prohibit tearing), so that the bag can be used again, and the desiccant and HIC card need to be reused to confirm whether it is normal. 4. In order to reduce the baking cycle of moisture-sensitive devices, moisture-sensitive devices that are not used up after packaging and do not exceed the workshop life should be immediately put into the electronic dehumidification moisture-proof machine in operation or stored using active desiccant and MBB seals, and the next batch of MSD materials in the electronic dehumidification and moisture-proof machine is preferred. 5.2 level and above MSD, if the storage conditions and workshop life requirements after packaging unpacking are exceeded, or the storage time under the sealed packaging is too long, (see the sealing date and storage conditions on the warning label, if the HIC card indicates that the humidity in the bag has reached or exceeded the humidity limit that needs to be baked) or the storage, transportation of the device caused by the damage to the sealing bag, the air leakage makes the device damp, and it must be returned to the material room for baking before use. 6. For the unused components of the production line after baking, a special person must be designated to re-do the vacuum packaging, and the vacuum packaging must be put in the qualified HIC card and desiccant. Visually see whether the vacuum effect after packaging meets the requirements, when packaging disc tape material, in order to avoid crushing the IC and the tray, the air in the bag can be allowed not to be pumped into a complete vacuum state, and the bag must be completely vacuumed when packaging the tray Tray material. Humidity indicator card HIC7. Double-sided reflow soldering process veneer, the design should fully consider the principle of MSD smd in the second reflow soldering surface, to ensure that all MSD exposure time on the veneer does not exceed its specified workshop life requirements before the second reflow soldering. 8. If the MSD is soldered after the patch, it must also be ensured that the MSD does not exceed its specified workshop life requirements before the wave soldering. 9. WHEN MSD is reflow soldering, the first strict control of the temperature change rate: the heating rate requires 3 °C/smax, the cooling rate requires 6 °C/smax, and the second is to strictly control the peak soldering temperature and high temperature duration (according to the manufacturer's requirements), each device must meet its own specifications. 10. The maximum number of MSD reflow soldering times is required to be 3 times. 11. In the process of dealing with moisture-sensitive devices and their components, it is necessary to do a good job of static protection. When vacuum encapsulation, special care should be taken to avoid excessive evacuation, causing the tray and its components to deform. 12. Electronic dehumidification moisture-proof machine internal storage has been unpacked MSD devices must be powered on 24 hours a day (it is strictly forbidden to power off during the holiday, vacuum sealing packaging is not required), each time the door is opened and closed as short as possible, after opening and closing the door must be spaced for more than 4 hours before the door can be opened and closed again, and record the "Electronic Dehumidification moisture-proof machine storage." / Material Time Record Table table. 13. In the normal use of electronic dehumidification and moisture-proof machine, MSL2~3 grade devices require ≤ in the cabinet to be 10%RH/≤30°C, MSL4 or above requires ≤5%RH/≤ 30°C in the cabinet, and the humidity in the cabinet is recorded three times a day (the overall holiday in the workshop can not be recorded). On the 15th of each month, the temperature and humidity measurement instrument is added to test the temperature and humidity, and recorded in the "Electronic Dehumidification and Moisture-proof Machine Temperature and Humidity Record Table", and there is an abnormality that needs to be timely feedback to the superior. The electronic dehumidification and moisture-proof machine must return to the specified humidity value within 1 hour after the normal operation such as opening and closing the door. 14. All bonded small plates that need to pass through the reflux furnace are controlled according to the MSL5 grade moisture sensitive device. 15. True empty packaging materials must be placed in areas where temperature and humidity are controlled when temporarily stored in the production line. MSD packaging is generally required to be stored under ≤ 30°C/60%RH environmental conditions. 16. Considering the workshop life overtime caused by the abnormality of the MSD patch during the second reflow soldering, and reducing the baking caused by moisture in the back-end maintenance, the workshop life of the MSL level 3 is modified from 168 hours to 120 hours) (the life of the 3-level device workshop in the MSD system is 48 hours, and the life of the other level workshop is 12 hours). When there is a difference between the workshop life in the system and the workshop life recorded by the "moisture sensitive device using the tracking card", the recording time of the "moisture sensitive device using the tracking card" shall prevail, and the workshop life in the system can be used as a reference basis when the abnormal recording is recorded. 17. All MSD devices must be unpacking, entering and leaving the oven, entering and leaving the electronic dehumidification and moisture-proof machine, and repacking must be data logged. 18. For MSD devices that are about to expire, the use should be closely tracked to prevent overdue. MSD devices that have expired and been damp, and those with moisture sensitive devices that use the tracking card unqualified label should be dried or baked within 24 hours, and it is strictly forbidden to shelve and not feedback and not to deal with. 19. MBB moisture-proof packaging should be continuous operation, once completed packaging. Humidity indicator cards should be packed away from desiccant and it is forbidden to shelve and overlap together.