Fabrication of Nickel-Gold Microsensor Using In Situ Laser-Induced Metal Deposition Technique

Abstract

Laser processing of silicon, as the most important material for microelectromechanical systems (MEMS), is commonly known and accepted as an effective manufacturing method to fabricate complex and precise micro components. Especially for the fabrication of micro hole grids, the recently developed high pulse repetition frequency (PRF) laser micro drilling technology is a valuable alternative to standard processing techniques. This paper discusses laser percussion drilling of silicon using ultrashort laser pulses at high average powers with the aim to drill through a material thickness of 100 µm. The main process influencing parameters, such as PRF and laser fluence were varied in order to identify optimal parameter settings for high quality and high throughput micro hole drilling. Furthermore, the effect of additional laser pulses, irradiated after drilling through, onto the micro hole geometry was examined. It will be shown that with increasing PRF and thus, lower laser fluence as a result of constant average laser power of the used laser system, the drilling time decreases significantly. This might be due to thermal accumulation induced by the applied highlyrepetitive pulses, leading to a higher substrate temperature which, in turn, lowers the energy needed for melting and evaporation. Surprisingly, this effect results in higher quality of the micro hole geometry without considerable debris at both, hole entrance and exit.

Laser-Assisted Surface Modification of Ni Microstructures with Au and Pt toward Cell Biocompatibility and High Enzyme-Free Glucose Sensing

“…This observation is consistent with the low electrical resistance of all the discussed materials (∼10, ∼17, and ∼19 Ω for Ni, Ni-Au, and Ni-Pt, respectively). It should also be noted that we were able to fabricate Ni-based microstructures with better morphology in comparison with Ni-Au structures previously deposited on glass-ceramics using a higher scanning speed, lower laser power, and lower concentration of the components.…”

In Situ Laser-Induced Fabrication of a Ruthenium-Based Microelectrode for Non-Enzymatic Dopamine Sensing

“…Accordingly, it is possible to synthesize metallic and bimetallic microstructures of different phase composition having a highly developed surface area and, as a result, exhibiting high electrocatalytic activity toward various analytes. Previously, we were able to fabricate sensor platforms based on copper [22], nickel [23], gold [24], platinum [25], iridium [25], molybdenum [26], silver [27], and cobalt [28], which are appropriate for glucose, hydrogen peroxide, and alanine enzymeless sensing. In the current study, we manufactured a ruthenium-based microelectrode to detect dopamine concentration.…”