Microfabrication of 3D metallic interconnects via direct laser writing and chemical metallization

Abstract

We present a developed method based on direct laser writing (DLW) and chemical metallization (CM) for microfabrication of three-dimensional (3D) metallic structures. Such approach enables manufacturing of free-form electro-conductive interconnects which can be used in integrated electric circuits such as micro-opto-electro-mechanical systems (MOEMS). The proposed technique employing ultrafast high repetition rate lasers enables efficient fabrication of 3D microstructures on dielectric as well as conductive substrates. The produced polymer links out of organic-inorganic composite matrix after CM serve as interconnects of separate metallic contacts; their dimensions are: height 15 μm, width 5 μm, length 35-45 μm, and they could provide 300 nΩm resistivity measured in a macroscopic way. This proves the techniques potential for creating integrated 3D electric circuits at microscale.

4D Printing: Enabling Technology for Microrobotics Applications

“…[162,163] There are other methods to fabricate a conductive polymeric structure using TPP, such as the use of a gold NPs precursor to create conductive channels [164,165] or other metals. [166] The main issue of using metals is that they have a high refractive index, which can interfere with the laser, resulting in poor resolution and even local heating of the resin that causes bubble formation.…”

Mesoscale 3D manufacturing: varying focusing conditions for efficient direct laser writing of polymers

“…Derivatives of this material can provide metal binding properties, thus enable creation of 3D metallic structures. 54,55 Sacrificial structures for optical application can be successfully made. For instance, the improvement of the fabrication accuracy of fiber tip microoptical components via mode field expansion was recently reported by Žukauskas et al 56 …”

Polymers for Regenerative Medicine Structures Made via Multiphoton 3D Lithography

“…The result is a metal layer just only on 3DLL-made structures. This was shown to lead to conductive 3D structures [172] or plasmonic functionality [10]. Magnetic interaction-based cell transportation was also shown [173].…”

“…The amount of silver plated onto the structures depends on the duration of these stages. Finally, during the plating, the structure is immersed in the reducing agent to form a smooth final layer of metal [10,172,173]. The result is a metal layer just only on 3DLL-made structures.…”