In semiconductor industry, deflashing is one of the important process steps during manufacturing of the semiconductor product. The term 'deflashing' is used to describe the removal of excessive mold bleed and resin bleed as a result of molding process in the assembly of the plastic devices as shown in figure 1. Mold bleed is black color material and is due to leakage while resin bleed is transparent/light yellowish-brown color and is due to separation of the epoxy resin from the fillers. Deflashing is important because if it is not done properly, defect such as solderability failure and blisters can be seen after Sn Plating process due to unremoved flashes as can been seen in figure 2 and figure 3. This paper objective is to describe in details the mechanism of deflashing for some of the common use of deflashing method available in the market. Chart 1 shows the common deflashing methods which are available in the semiconductor industry. This paper also will provide the correct deflashing method to be used in order to achieve robust deflashing quality which will not subsequently impact the plating quality and reliability performance. By providing the correct deflashing method or deflashing design rules, we can have a clear guidelines for all the existing and new development on what kind of deflashing method need to be used for a defined package platform. A universal deflashing method cannot be used for all type of packages. But at the same time we should try to standardize the use of deflashing chemistry from each deflashing method in order to reduce the complexity and variation within the company.
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