Laser Cutting Silicon Wafer

In addition complex features such as channels and pockets and channels can be machined in silicon wafers.

Laser cutting silicon wafer.

Sapphire silicon wafer cutter. Solutions are available for machining smaller diameter wafers from larger ones solar cell downsizing or silicon stencil cutting. Material thickness up to 1mm. However laser ablation has its own problems.

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. Cut features are round holes with no cracking or rough edges.

Demonstration of cutting features into 1 5 mm thick silicon wafers using a laser micromachining system equipped with a qcw laser. We tried cutting a silicon wafer with fabool laser mini 1 6w and 3 5w model. Traditionally silicon wafers have been cut with diamond saws occasionally using a scribe and break process which have the limitation that they can only cut straight lines and suffer from edge chipping and frequency doubled vanadate lasers which are both slow and expensive to operate as is the microjet process. The same system can be used to downsize larger silicon wafers for use in smaller format processing tools.

The figure shows 700 µm wafer downsizing top view and side view. 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. Laser cutting of silicon wafers is possible in all sizes and thicknesses with feature sizes as small as 20 microns. Due to the reflection it only made slight scratch and could not cut.