An optoelectronic device has at least a first facet (S), a first waveguide
(2) and a second waveguide (3). The waveguides are substantially
coincident at the first facet (6), such that light travelling along the
first waveguide (2) is reflected into the second waveguide (3) by the
first facet (6). The first facet (6) is formed by precision cleaving.
Preferably an etch feature is incorporated in the same mask level as that
to define the waveguide core.