Patent ID: 7865053

Claim:
An apparatus, comprising: a substrate having a surface; an optical waveguide having a ridge-shaped semiconductor optical core, the ridge-shaped semiconductor optical core being located over the surface, and not including a p-n junction; a first semiconductor slab being in contact with a first portion of the ridge-shaped semiconductor optical core, wherein the first semiconductor slab includes a first relatively low doped region proximate the ridge-shaped semiconductor optical core and a first relatively high doped region distal the ridge-shaped semiconductor optical core, and further wherein a peak dopant level of the first relatively low doped region and a peak dopant level of the first relatively high doped region are greater than a peak dopant level of the ridge-shaped semiconductor optical core, and further wherein an interface where the first semiconductor slab contacts the ridge-shaped semiconductor optical core does not form a p-n junction; and a second semiconductor slab being in contact with a second portion of the ridge-shaped semiconductor optical core, the second semiconductor slab being farther from the surface than the first semiconductor slab.