Optical element, process for producing optical element, coating equipment, and coating method

Abstract

A method of producing optical elements using a substrate having a recess, which is capable of easily removing a film in the recess, and optical elements formed. The optical element comprises a substrate 1, an optical waveguide structure layer 10 of resin disposed in a part of the region on the substrate 1, and a recess 21 formed in the region where the optical waveguide structure layer 10 is not disposed. The optical waveguide structure layer 10 includes an optical waveguide 4 and a clad layer. A coupler layer is disposed between the substrate 1 and the optical waveguide structure layer 10, and the film thickness distribution range of the coupler layer in the region below the optical waveguide 4 is such that the minimum film thickness is not more than 30 angstroms and the maximum film thickness is not less than 20 angstroms.

1 . A process for producing optical elements, which comprises: 
 a first step of forming a film of an organozirconium compound on a substrate on which a recess has been formed; and    a second step of forming a resin layer on the film of said organozirconium compound, wherein    said first step comprises a coating step of disposing said substrate in a solvent atmosphere, in a state in which said substrate is coated thereon with a solution containing said organozirconium compound and a solvent; and the solvent constituting the solvent atmosphere is the same as the solvent contained in the solution.    
   
   
       2 . The process for producing optical elements according to  claim 1 , wherein said coating step is the step of disposing said substrate in a container filled with said solvent, and rotating said substrate to coat the surface of said substrate with said solvent.  
   
   
       3 . The process for producing optical elements according to  claim 2 , wherein said container, at least its part facing said substrate, is rotated in the same direction as said substrate.  
   
   
       4 . The process for producing optical elements according to  claim 3 , wherein said container is kept closed during the rotation.  
   
   
       5 . The process for producing optical elements according to  claim 3 , wherein the rotation of said substrate is stopped, which is thereafter kept to stand still for a predetermined time, and thereafter said container is opened to take out the coated substrate.  
   
   
       6 . The process for producing optical elements according to  claim 3 , wherein said substrate is rotated together with said container.  
   
   
       7 . The process for producing optical elements according to  claim 6 , wherein said container is kept closed during the rotation.  
   
   
       8 . The process for producing optical elements according to  claim 6 , wherein the rotation of said substrate is stopped, which is thereafter kept to stand still for a predetermined time, and thereafter said container is opened to take out the coated substrate.  
   
   
       9 . The process for producing optical elements according to  claim 2 , wherein said container is kept closed during the rotation.  
   
   
       10 . The process for producing optical elements according to  claim 2 , wherein the rotation of said substrate is stopped, which is thereafter kept to stand still for a predetermined time, and thereafter said container is opened to take out the coated substrate.  
   
   
       11 . The process for producing optical elements according to  claim 10 , wherein, after said substrate has been kept to stand still and before said container is opened, the solvent atmosphere in said container is exhausted at a predetermined flow rate.  
   
   
       12 . The process for producing optical elements according to  claim 11 , wherein the rotation of said substrate is stopped, which is hereafter kept to stand still for a predetermined time, and thereafter said container is opened to take out the coated substrate.  
   
   
       13 . A coating equipment comprising: 
 a container having an opening through which a substrate on which a recess has been formed is to be put in and out;    a cover with which the opening of the container is covered;    a substrate mount which supports thereon the substrate disposed in the container;    a rotary drive which rotates the substrate mount together with the container; and    a discharge passage formed extending from the inside of the container toward the outside of the container, for discharging at least one of a solution and an atmosphere inside the container to the outside of the container,    wherein said discharge passage comprises an inside opening on the inside of the container and an outside opening on the outside of the container, and    wherein said outside opening is disposed nearer to the rotational axis of said container than to said inside opening.    
   
   
       14 . A coating equipment comprising: 
 a container having an opening through which a substrate on which a recess has been formed is to be put in and out;    a cover with which the opening of the container is covered;    a substrate mount which supports thereon the substrate disposed in the container;    a rotary drive which rotates the substrate mount in the container; and    a discharge vent through which an atmosphere inside the container is to be discharged to the outside,    wherein said discharge vent is fitted with a control means for controlling the discharge rate of the atmosphere.    
   
   
       15 . A method of coating with a solution a surface of a substrate having a recess, which comprises: 
 disposing the substrate in a closed container filled with an atmosphere of a solvent contained in the coating solution; and    rotating the substrate together with the closed container to coat the surface of the substrate with the solution.    
   
   
       16 . A method of coating with a solution a surface of a substrate having a recess, which comprises: 
 disposing the substrate in a closed container filled with an atmosphere of a solvent contained in the coating solution;    rotating the substrate to coat the surface of the substrate with the solution;    stopping the rotation of the substrate and thereafter keeping the substrate to stand still for a predetermined time; and    discharging at a predetermined rate the solvent atmosphere held in the space where the substrate stands disposed.    
   
   
       17 . A method of coating with a solution a surface of a substrate having a recess, which comprises: 
 disposing the substrate in a closed container filled with an atmosphere of a solvent contained in the coating solution;    rotating the substrate to coat the surface of the substrate with the solution; and    discharging at a predetermined rate the solvent atmosphere held in the space where the substrate stands disposed.