Area Array Solder Bumping at the Substrate Level
Area Array Solder Bumping at the Substrate Level Alchemy Electronics
Solder Bumping Process Start Excess Solder Removal Dry Out Alchemy Electronics Bake De-Balling Re-Balling Cleaning End
Baking Process The baking process dries out the component and eliminates moisture that can cause the component to delaminate or “popcorn” during the re-balling process. The baking process is done at 125 o C for 24 hours. This bake out will prepare the component for a wave soldering process. Start Remove Component from Oven Alchemy Electronics Placed Component in Oven End Bake 24 Hrs /1250 C
De-Balling Process The De-Balling process dissolves all solder spheres from the component by using a process called dissolution of metallization. During this process the component substrate is run through the crest of the dynamic bath of molten solder alloy, which washes away the content of all solder spheres attached to the substrate of the component. This solder alloy contained in the dynamic bath, which melts at 138 o. C is heated to a required temperature at around 175 o. C to precipitate the content of the solder spheres into the bath of molten solder. Start Visual Inspection Alchemy Electronics Applied Flux to Component End Remove Solder Spheres
Excess Solder Removal Process The solder removal process eliminates all extra solder left on the component pads by using a blade tip soldering iron and a de-soldering braid, and since the pads are filled with a new solder alloy that melts only at 135 o. C, the component is exposed to a very low thermal stress. Start Visual Inspection Alchemy Electronics Applied Flux to Component End Remove Solder with Iron and Braid
Re-Balling Process The Re-Balling process is performed using a unique technique called attach-detach-reflow. This process starts by adding a water soluble flux to the component, which then is placed into a fixture. After the fixture has been aligned to the components the solder spheres are added and lined up, then the component is removed from the fixture and placed into the hot air convection oven station to start the re-flow heat cycle. This unique technique allows for the adhesion of the solder spheres to the solder pads by a chemical attraction between the spheres and the component substrate pads. Start Add Solder Ball to Fixture Re-flow Component Alchemy Electronics Add Flux Attach Fixture to Component Detach Component From Fixture Place Components into Oven Inspection End
Cleaning Process It is very important to remove any contamination from a component because it can cause electrical shorts or corrosion. The cleaning process used at Alchemy Electronics is unique because we not only use a DI water bath to remove any ionic residues but we also use an alkaline base solution bath to eliminate all non ionic contamination. This way we make sure that any residues that were deposited in the component are removed regardless of its composition. Start Alkaline Base Solution Inspection End Alchemy Electronics DI Water Bath
Dry Out Process Alchemy dry out process is used to bake the component at a temperature of 125 o. C for 25 minutes. This process allows the quality inspection team to perform a visual inspection to make sure that the components do not have any foreign particles. Once the bake process is completed all components are placed into an ESD safe moisture barrier bag along with fresh desiccant The desiccant will help keep the components dry during storage and shipping. Start Dry Out Place in Bag End Alchemy Electronics Inspection
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