Patent ID: 6828589
Filing Date: 2004-12-07
Classification: H01S

Abstract:
A manufacturing method for collectively manufacturing, on a single substrate, an optical semiconductor device comprising a plurality of semiconductor lasers which emit longitudinal single mode laser lights having different wavelengths due to a distribution feedback operation of a periodic change of the refractive indexes in the respective semiconductor lasers, said method comprising:forming at least one overlying semiconductor layer during manufacture so that the refractive indexes of diffraction grating embedded semiconductor layers are decreased (or increased) so as to cancel a difference of coupling coefficients of respective semiconductor lasers whose coupling coefficients are increased (or decreased) when diffraction gratings for generating a distribution feedback operation are formed in a same configuration and the refractive indexes of said diffraction grating embedded semiconductor layers are fixed at a same value, said forming including canceling said difference of coupling coefficients thereby providing at least one diffraction grating embedded semiconductor layer that has been adjusted to provide a substantially constant coupling coefficient for all of said plurality of semiconductor lasers on said optical semiconductor device.