Surface-enhanced Raman spectroscopy (SERS) is a powerful non-destructive molecule identification technique. The technique is made viable by the enhancement of the Raman effect which is caused by metallic nanoparticle (MNP) structures. A fabrication method that can manufacture hig
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Surface-enhanced Raman spectroscopy (SERS) is a powerful non-destructive molecule identification technique. The technique is made viable by the enhancement of the Raman effect which is caused by metallic nanoparticle (MNP) structures. A fabrication method that can manufacture highly consistent SERS substrates is important. Aerosol Direct Write (ADW) is a promising method to achieve consistent SERS substrates. Previous research did not achieve reproducible substrates due to inconsistencies in particle deposition. To improve the quality of SERS substrates fabricated using ADW, key factors within the ADW setup contributing to the substrate quality are identified and analysed. A particle deposition model is created to analyse the impact of those key factors on the substrate quality and to analyse if different operating velocities of the moving stage can minimise the impact of those key factors. The deposition model results are validated by fabricating substrates using a range of operating velocities. It is found that the nozzle diameter has a linear correlation with the spot size. The particle generation is inconsistent and a dominant factor for the SERS substrate quality. The effect of the fluctuating particle generation rate can be minimised by multiple path coverages and higher operation velocities. It is found that the XYZ-stage in the used setup operates optimally between 1000 and 2000 micrometer per second. The deposition model correctly showed that the particle generation rate is the dominant factor for the substrate quality and correctly predicted the ideal operating velocity of the XYZ-stage used in the setup. The model can be used in the future to find an ideal operating velocity and to look at the effects of stage movement characteristics and particle generation fluctuations in ADW setups. SERS measurements show that the SERS substrate fabricated at the ideal operating velocity performed more consistently than substrates fabricated at other velocities.