Cutting of Transparent Materials by Selective Laser-induced Etching

Micro part cut of sapphire and resulting hole. The kerf is about 1.4 m in width and 500 m deep. Copyright: Fraunhofer ILT Cube Cut in Sapphire - Micro part cut of sapphire and resulting hole. The kerf is about 1.4 m in width and 500 m deep.

Shaped parts and holes are cut in transparent materials like sapphire and glass by in-volume selective laser-induced etching.

Cutting by In-volume Selective Laser-induced Etching
The miniaturization of products in micro optics, medical technology and micro system technology requires transparent components with structure sizes in the micrometer range and accuracies of about 100 nm.

Holes in fused silica with a diameter of 133 m and cut-out cylinder. The precision is about 1 m. Copyright: Fraunhofer ILT Holes in fused silica with a diameter of 133 m and cut-out cylinder. The precision is about 1 m.

By means of ISLE slits with large aspect ratio are produced in glasses and sapphire.
Slits of 1 m width, 125 m height and 10 mm length with surface qualities < 100 nm are cut in sapphire. Furthermore, by selectively modifying a closed plane and subsequent etching both the micro component and the shaped hole result with a kerfs width of 1-2 m in sapphire or a kerfs width of 6-10 m in glass. The roughness of the cut planes is quite low, e.g. the root mean spare roughness is Rrms < 100 nm and the peak to peak roughness Rz ~ 1 m.