Makers employing Low-k material and copper in high-speed devices experience significant bottlenecks,
as this material is difficult to blade-dice at standard speeds. Further, acceptable cut quality is hard to obtain.
DISCO's engineers have developed an application that solves these issues.
Application
Laser grooving process
First, the DFL7160 rapidly makes two laser grooves in the dicing street - either "Pi Laser Grooving" or "Omega Laser Grooving"; then the wafer is blade-diced at standard speed. This application achieves excellent throughput yet greatly reduces or eliminates chipping, delamination and other cut-quality issues.
Pi (π) laser grooving followed by step cut blade
dicing.
Little or no chipping and delamination.
Equipment
Precision and Ease of Use
The DFL7160 (300 mm compatible) Fully Automatic Laser Saw utilizes short pulse laser
technology to groove the streets of Low-k and Cu wafers with little or no heat damage. An LCD touch screen
graphical user interface allows for excellent ease of operation.
Photo 1: DFL7160
Photo 2: Laser process
Laser
Cutting Quality
The DFL7160 focuses a short pulse UV laser on the surface of the wafer. Each pulse
is absorbed by the Low-k material. After successive laser pulses, sufficient energy is absorbed to cause
the Low-k material to vaporize. The vaporized material carries away the energy from the interaction, thereby
minimizing heat transfer to the surrounding material.
Laser grooving process
Laser grooving with long pulse laser beam (material: silicon).
Recast and heat damage are clearly visible.
Laser grooving with short pulse laser beam (material: silicon).
Little or no recast or heat damage is visible.
