Highly efficient UV and DUV laser micro- and nanoprocessing for microelectronics applications

Modern microelectronics applications require processing technologies that not only provide micron and sub-micron resolution, but also the highest throughput requirements with minimal defectivity and debris generation. Classical laser processing with infrared or visible wavelengths is challenged to limit the size of the affected regions to the sub-10µm range in non-metals, even when using ultrashort pulses. Lasers with wavelengths in the UV and DUV, however, offer linear absorption in many wide bandgap materials, resulting in a massive reduction in penetration depth and a more confined interaction volume. This opens the possibility of significantly improving both resolution and quality of laser processing, while maintaining high maximum throughput due to improved efficiency. This paper presents the results of investigations into several promising microelectronics applications, including sub-micron surface structuring, high-precision laser lift-off of GaN, high-speed grooving of silicon, and the generation of quantum defects in SiC.