3D-fibre channels in silicon by electrical breakdown—New opportunities for optical fibre alignment and microfluidics

Very precise 3D fibre channels are fabricated by defined electrical breakdown in crystalline silicon followed by wet anisotropic etching in KOH: it is an extension of the well-known V-grooves that are already extensively used in fibre assembly. It allows to integrate large 2D-arrays of precisely aligned fibres in {110}-silicon or to adjust four fibres in a pyramid-shaped configuration into {100}-silicon in such a way that they all meet in a single point. The fabrication technology is presented and possible applications are described.