Patent ID: 8236590

Claim:
A method for forming an optical device comprising: forming a first layer formed of a first material; forming a second layer formed of a second material different from the first material; selectively etching the second layer to form at least one discrete area; forming one or more additional layers of at least a third material different from the second material; forming a waveguide in the at least one additional layers; removing a portion of the at least one additional layers adjacent the waveguide such that at least one surface of the at least one discrete area is exposed; forming a support layer extending across the at least one surface of the at least one discrete area; forming an opening in the support layer such that a portion of the at least one surface is exposed; exposing the at least one discrete area through the opening in the support layer to an etchant that removes the second material faster than the first and third materials; and wherein the first and third materials include InP and wherein the second material includes InGaAs or InGaAsP.