Precautions for Electronic Components Storage

How does humidity affect electronic components and the whole machine

Most electronic products require operation and storage under dry conditions. According to statistics, more than a quarter of the world’s industrially manufactured defective products are related to the hazards of moisture each year. For the electronics industry, the hazard of moisture has become one of the main factors affecting product quality.

(1) Integrated circuit: The harm of moisture to the semiconductor industry is mainly manifested in that moisture can penetrate into the IC through the IC plastic package and through the gaps such as the pins, resulting in IC moisture absorption. In the heating process of the SMT process, water vapor is formed, and the pressure generated causes the IC resin package to crack and oxidize the internal metal of the IC device, resulting in product failure. In addition, when the device is soldered on the PCB board, due to the release of water vapor pressure, it will also cause virtual soldering. According to the IPC-M190 J-STD-033 standard, SMD components exposed to a high-humidity air environment must be placed in a drying box with humidity below 10% RH for 10 times the exposure time to restore the component’s “workshop” Life” to avoid scrap and ensure safety.

(2) Liquid crystal devices: Although the glass substrates, polarizers, and filters of liquid crystal devices such as liquid crystal displays need to be cleaned and dried during the production process, they will still be affected by moisture after they are cooled down, reducing the pass rate of products. Therefore, after cleaning and drying, it should be stored in a dry environment below 40% RH.

(3) Other electronic devices: capacitors, ceramic devices, connectors, switch parts, solder, PCB, crystals, silicon wafers, quartz oscillators, SMT glue, electrode material adhesives, electronic pastes, high-brightness devices, etc. Will be harmed by moisture.

(4) Electronic devices during operation: between semi-finished products in packaging and the next process; before PCB packaging and after packaging to power-on; IC, BGA, PCB, etc. after unpacking but not used up; waiting for the tin furnace Welded devices; devices to be reheated after baking; finished products that have not been packaged, etc., will all be harmed by moisture.

(5) The finished electronic complete machine will also be harmed by moisture during the storage process. If the storage time is too long in a high humidity environment, it will cause malfunctions. For computer boards, CPUs, etc., the golden fingers will be oxidized, resulting in poor contact and malfunctions. The humidity of the production and storage environment of electronic industrial products should be below 40%. Some varieties also require lower humidity.