Laser Cutting Silicon Wafer

Sapphire silicon wafer cutter.

Laser cutting silicon wafer.

Demonstration of cutting features into 1 5 mm thick silicon wafers using a laser micromachining system equipped with a qcw laser. Vaporizing the wafer with a laser along the dicing path creates molten debris and microcracks. Cut features are round holes with no cracking or rough edges. Laser cutting of silicon wafers is possible in all sizes and thicknesses with feature sizes as small as 20 microns.

We tried cutting a silicon wafer with fabool laser mini 1 6w and 3 5w model. The figure shows 700 µm wafer downsizing top view and side view. However laser ablation has its own problems. For silicon wafers less than 100 μm thick laser ablation offers an alternative to the blade technique which is too powerful for the delicate thin wafers.

Material thickness up to 1mm. All that is required is a drawing to getting started. Due to the reflection it only made slight scratch and could not cut. In addition complex features such as channels and pockets and channels can be machined in silicon wafers.

Dicing of silicon wafers may also be performed by a laser based technique the so called stealth dicing process. Blackstar is a wafer dicing system utilizing fantom width laser dicing technology fwldt invented and patented by laser photonics and modified to accommodate the requirements of a silicon wafer singulation process without affecting the existent dicing method processes or procedures. It works as a two stage process in which defect regions are firstly introduced into the wafer by scanning the beam along intended cutting lines and secondly an underlying carrier membrane is expanded to induce fracture. The same system can be used to downsize larger silicon wafers for use in smaller format processing tools.