Repulsive magnetic field enhanced laser drilling via backside chemical-assisted etching of SiC substrates

The fabrication of high-quality micro-holes in silicon carbide (SiC) substrates is essential for enabling internal circuit interconnections in advanced microelectronic devices. To enhance the micro-hole quality and improve the aspect ratio of micro-holes in SiC substrates through laser drilling, we propose a novel method that utilizes a repulsive magnetic field enhanced laser drilling via backside chemical-assisted etching. The experimental results demonstrate that the application of a repulsive magnetic field significantly reduces the diameter of the entrance and reduces the taper, increases the exit diameter, and improves the roundness of micro-holes. By optimizing experimental parameters, a high aspect ratio of 15:1 and a high verticality of 0.6° are achieved. We further analyze the enhancement mechanism. This approach provides a viable strategy to manufacture high-density interconnects in advanced microelectronic systems.