High-throughput pulsed laser manufacturing etch process for complex and released structures from bulk 4H-SiC

This paper documents the implementation of a one-step process for the manufacture of complex and released structures from bulk silicon carbide (4H-SiC) using a pulsed neodymium-doped yttrium orthovanadate (Nd/YVO
₄
) laser. The process employs a pulsed laser (~1 kW) to scribe a crosshatch pattern in the 4H-SiC substrate, etching features directly from the bulk material. The effective etch rate and resulting surface roughness of the process are characterized with respect to the scribe speed of the laser, the scribed laser line spacing, and the number of laser passes. Finally, a planetary gear assembly is rapidly (15 minutes) manufactured from bulk 4H-SiC. The technique described is a step toward cheaply and efficiently manufacturing SiC microstructures at the die level in lieu of more expensive fabrication techniques such as deep reactive ion etching (DRIE).