Method of producing a rib waveguide

Abstract

A method of producing an optical grating component including only a single continuous grating field formed in a longitudinal waveguide rib, the method including the steps of defining a grating in an optic chip including a portion thereof through which the longitudinal waveguide rib is to extend, and then defining the lateral edges of the longitudinal rib in the optic chip, whereby any portion of the grating extending laterally beyond the lateral width of the rib is removed in the step of defining the lateral edges of the rib leaving a single continuous grating field that has straight lateral grating boundaries that are laterally aligned with the straight lateral edges of the rib.

What is claimed is:  
     
         1 . A method of producing an optical grating component including only a single continuous grating field formed in a longitudinal waveguide rib, the method including the steps of defining a grating in an optic chip including a portion thereof through which the longitudinal waveguide rib is to extend, and then defining the lateral edges of the longitudinal rib in the optic chip, whereby any portion of the grating extending laterally beyond the lateral width of the rib is removed in the step of defining the lateral edges of the rib leaving a single continuous grating field that is laterally aligned with the lateral edges of the rib.  
     
     
         2 . A method of producing an optical grating component including a grating with straight lateral grating boundaries in a length of longitudinal waveguide rib of uniform lateral width, the method including the steps of (a) defining a grating in an optic chip including a portion thereof through which said length of the longitudinal rib is to extend, and then (b) defining the lateral edges of said length of the longitudinal rib in the optic chip, whereby any portion of the grating extending laterally beyond the lateral uniform width of said length of the rib is removed in the step of defining the lateral edges of the rib leaving a grating with straight lateral grating boundaries that are laterally aligned with the lateral edges of said length the rib.  
     
     
         3 . A method of producing an optical grating component according to  claim 1 , wherein the longitudinal waveguide rib includes a first section having the grating formed therein and a second section extending longitudinally from the first section without a grating formed therein, and wherein the grating is defined in a selected portion of an optic chip including a portion thereof through which said first section of the longitudinal rib is to extend but excluding any portion of the optic chip through which the second section is to extend.  
     
     
         4 . A method of producing an optical grating component according to  claim 2 , wherein the longitudinal waveguide rib includes a first section having the grating formed therein and a second section extending longitudinally from the first section without a grating formed therein, and wherein the grating is defined in a selected portion of an optic chip including a portion thereof through which said first section of the longitudinal rib is to extend but excluding any portion of the optic chip through which the second section is to extend.  
     
     
         5 . A method according to  claim 1 , wherein the grating is formed by a non-mask technique.  
     
     
         6 . A method according to  claim 2 , wherein the grating is formed by a non-mask technique.  
     
     
         7 . A method according to  claim 1 , wherein the optic chip is a silicon optic chip.  
     
     
         8 . A method according to  claim 2 , wherein the optic chip is a silicon optic chip.  
     
     
         9 . A method of producing a silicon rib waveguide including a grating in a portion thereof, the method including the steps of: (a) providing a grating mask over a selected portion of a silicon optic chip for use in defining the grating; (b) then defining a rib in the silicon optic chip using a rib mask formed over the grating mask, the step of defining the rib removing any of the grating mask that may extend laterally beyond the lateral width of the rib; and (c) etching the optic chip through the grating mask to define a grating in the rib, whereby the grating is aligned laterally with the lateral edges of the rib; wherein photoresist is used to form the rib mask  
     
     
         10 . A method of producing a silicon rib waveguide including a grating in a portion thereof, the method including the steps of: (a) providing a grating mask over a selected portion of a silicon optic chip for use in defining the grating; (b) then defining a rib in the silicon optic chip using a rib mask formed over the grating mask, the step of defining the rib removing any of the grating mask that may extend laterally beyond the lateral width of the rib; and (c) etching the optic chip through the grating mask to define a grating in the rib, whereby the grating is aligned laterally with the lateral edges of the rib; wherein the grating mask is a thermal oxide mask.