New method for low cost and efficient optical connections between singlemode fibres and silica guides

A new method is presented of using dry etched U grooves in silicon able to give low cost and efficient optical connections without any active alignment between singlemodc fibres and silica waveguides fabricated on silicon substrates. A rugged assembly including a 35 mm long channel guide with two pigtails and exhibiting total power loss lower than 0.8 dB has been demonstrated.