- Multi-Beam is mainly used for Si, SiC, Sapphire, LiNbO3, LiTaO3, Mold compound and GaN materials.
- Scribing is a process where a scribe of a certain depth is made into the wafer substrate. The depth of the scribe into the material depends on the material thickness.
- In a subsequent step a mechanical force is exerted onto the die to propagate the scribe and create a crack. (scribe & break process)
- Scribing is applied to open the active layer and keep a high die strength
- The number of spots and distance between the spots can be varied.
- Depending on the choice of DOE, the recast width, burr height, HAZ, UPH and DIE strength will vary.
- Beams with a larger spot-to-spot distance result in a lower Heat Affected Zone (HAZ)
Laser Scribing process explained
For certain wafer separation technologies it is not required or efficient to use a laser full cut dicing process to singulate the substrate thickness. Apart from combining laser and saw blade as mentioned in Matrix concept also a laser scribe process can be used. In a laser scribing process a scribe is made into the wafer substrate of a certain depth. In a subsequent step a mechanical force is exerted onto the die to create a cleave/crack which propagates from the scribe. This is referred to as a scribe and break process. The depth of the scribe into the material depends on the thickness of the substrate, what type of material and the die size. In either case ASMPT’s multi beam laser technology can be used to create the required depth and width of the scribe with a high productivity and minimal HAZ. An additional Process flow in which a laser scribe can be used is plasma dicing. In a plasma dicing process step, also referred to as Deep Reactive Ion Etching (DRIE), Si is removed by a plasma process (we zouden een link naar SPTS kunnen plaatsen). A DRIE process can not etch other materials such a SiO, polymers or metals, therefore a laser process is needed to remove these top layers prior to applying a DRIE process and therefore the laser enable the plasma dicing process.