Studies on Microdrilling of NbN Superconductor using Pulsed Laser Ablation

Superconducting materials are of importance in making highly efficient terahertz components for space applications.The creation of microstructure using laser ablation process was provided.A nanosecond pulsed Nd: YAG laser with the maximum energy of 0.6 J was utilized to make microscale features in NbN superconducting material.The material was ablated at different energy levels and the corresponding spectra were captured with spectrometer through fiber optic cable.The exact energy required to ablate the NbN material was obtained experimentally.The experimental part utilizes a 1064 nm ns-pulsed laser as a source for ablation.The same process has been repeated in high-pressure conditions of 4 atm and 8 atm in a vacuum chamber.The ablation rate was decreased as the pressure level in the vacuum chamber has been increased; solidification of molten material was observed under high-pressure conditions.The effects of laser intensity and scanning speed in the ablation rate of NbN material have been experimentally verified.The poor thermal conductivity of the NbN makes the nanosecond laser ablation as an effective process for micromachining with minimal heat affected area.The morphological properties of the ablated structure were evaluated using optical microscopic images.