A process for shifting the bandgap energy of a quantum well layer (e.g., a
III-V semiconductor quantum well layer) without inducing complex crystal
defects or generating significant free carriers. The process includes
introducing ions (e.g., deep-level ion species) into a quantum well
structure at an elevated temperature, for example, in the range of from
about 200.degree. C. to about 700.degree. C. The quantum well structure
that has had ions introduced therein includes an upper barrier layer, a
lower barrier layer and a quantum well layer. The quantum well layer is
disposed between the upper barrier layer and the lower barrier layer. The
quantum well structure is then thermally annealed, thereby inducing
quantum well intermixing (QWI) in the quantum well structure and shifting
the bandgap energy of the quantum well layer. Also, a photonic device
assembly that includes a plurality of operably coupled photonic devices
monolithically integrated on a single substrate using the process
described above.
