Deflash - Semiconductors
Process Objective
As a pre-treatment of plating process, the burrs which occurred at resin molding for semiconductor packaging, are removed.
Types of burrs
Dam-burrs | Side-burrs | Flash-burrs |
---|---|---|
![]() Burrs that fills out among leads. | ![]() Thick burrs aside of leads. | ![]() Thinner burrs on leads and heat sink. |
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It is possible to remove burrs by conventional burr removal method. | ||
Demand for flash-burr removal is increasing due to the technical trends of smaller packaging and thinner product. |
Therefore a burr removal with reasonable price and stable quality is necessary.
Problems of flash-burr removal

Benefits of flash-burr removal by wet-blasting
- 1) Burrs can be perfectly removed by uniform treatment.
- 2) Package does not become white.
- 3) Processing power can be controlled with sub-micron order.
The characteristic of Wet-blast
1) By the precision physical cleaning, flash-burrs on electrode plane can be perfectly removed.

Principles of cleaning
Dirt and foreign objects are removed together with the surface of the work piece by the impact given by the energy of particles and water in high speed.
2) Reduction of non-uniform processing by using originally developed wide gun.
Conventional gun
Simultaneous projections by multiple guns.
Non-uniform processing occurs.
Wide gun
Projection by one gun in accordance with the processing width.
It is possible to process the whole surface uniformly.
3) It is possible to suppress damages to the package applied by loose abrasive processing.
Less pressure onto the work piece is applied by continuous pulse processing to its surface
4) It is possible to suppress damages to the surface of the package applied by low pressured micro-particle processing.

Example of flash-burrs
Untreated | After Wet-blasting process | |
---|---|---|
Package Surface![]() | ![]() | ![]() |
Heat sink surface ![]() | ![]() | ![]() |
Heat sink surface Electron microscope(SEM) | ![]() | ![]() |
Heat sink surface Laser microscope | ![]() | ![]() |
Examples of associated equipment (mini PFE 100)
Feature
- Inline processing from wet-blasting to water rinse followed by cutwater is applicable.
- Whole front /back surface processing is applicable by using our own wide gun.
- Higher spatial usability by downsizing the cell is realized.
- Precision physical cleaning using micro-particles are realized.

Process

Spec
Size | 1200W×1250D×1600H |
---|---|
Work size | Width:20-80mm Length:100-250mm Thickness:0.1-1.5mm Acceptable warpage level of work piece:Less than 1mm of center warpage |
Conveyor transportation speed | 0.1-3.0m/min |
Gun | Wide Gun 90mm×1.0mm One each for top and bottom |
Power supply | AC200V,50/60Hz, 3 phases |
Power consumption | 2.6kW (Total rated apparent power of all the cell) |
Air supply pressure | 0.5MPa or more, 0.7MPa and below |
Air consumption | 4.1m3/min (NTP at 0.25MPa of preset blast air pressure) |
Option |