Copyright © 2014 www.lybga.com. All Rights Reserved. LiYang (LY) Welding Equipment Co., Ltd.
BGA preservation and use
BGA preservation and use
drying conditions, the operating personnel should be strict compliance with the operating process,
avoid components in the assembly is affected. In general, the ideal environment for the preservation
of 200C-250C is BGA, the humidity is less than 10%RH (has better nitrogen protection).
In most cases, we in the packaging of components is not open before will pay attention to BGA
moisture treatment. At the same time, we should also pay attention to packaging of components
after being hit for the installation and welding process is not to be exposed to the time, to prevent
the components affected causes the welding quality decline or components of the electrical properties
of the change. The next table is humidity sensitive grade classification, which is shown in the assembly
process, once the seal moisture packaging is opened, the components must be used for the installation,
welding the corresponding time. Generally speaking, the BGA belongs to the humidity sensitive grade
of 5 levels.
If the use of components stored in the conditions of nitrogen, then the time can be extended to.
The effect of approximately every 4-5 hours of dry nitrogen can be prolonged by 1 hours of air exposure.
In the assembly process we often encounter such a situation, the components of the packaging is opened
cannot in the corresponding time after use and the time of exposure over the table 1 provides the time,
then before the next use in order to make the component has good solderability, we suggest to bake the
BGA components. Baking conditions: temperature 1250C, relative humidity is less than 60% RH.
Baking temperature most don't more than 1250C, because high temperature will cause solder and
components at the junction of the microstructure changes, and when these components into the
stage of reflow, easily lead to disconnection between the solder and components package, resulting
in SMT assembly quality problem, we will think is the components of quality problems caused by.
But the temperature of the roast is too low, then it can't play the role of the desiccant.. In the
conditions permit, we suggest that in the assembly components baking, is conducive to the
elimination of the internal moisture of the BGA and improve heat resistance of BGA, reducing
components into reflow by thermal shock on the device's influence. BGA components out of the
baking, natural cooling for half an hour before the assembly operation.