CMOS-compatible process for fibre alignment grooves in silicon

Reactive ion etching is proposed as an alternative to wet etching silicon to form optical alignment grooves for optical interconnection in silicon. The dependence of the etched groove shape as a function of RIE pressure was measured. The groove shape was measured as the degree of groove conformance to a semicircular profile. An optimal pressure of 300 mTorr was determined and the undercutting and depth of the etched grooves as a function of photo-mask was measured.