Manufacturing Method of Photonic Crystal

Abstract

A manufacturing method of a photonic crystal is provided. In the method, a high-refractive-index material is conformally deposited on an exposed portion of a periodic template composed of a low-refractive-index material by an atomic layer deposition process so that a difference in refractive indices or dielectric constants between the template and adjacent air becomes greater, which makes it possible to form a three-dimensional photonic crystal having a superior photonic bandgap. Herein, the three-dimensional structure may be prepared by a layer-by-layer method.

What is claimed is: 
     
         1 . A method of manufacturing a photonic crystal with a photonic bandgap, the method comprising the steps of:
 forming a periodic three-dimensional structure comprising a first material having a first refractive index and a plurality of gaps; and   conformally depositing exposed surfaces of the periodic three-dimensional structure with a second material having a second refractive index greater than the first refractive index.   
     
     
         2 . The method of  claim 1 , wherein the step of conformally depositing is performed using at least one of an atomic layer deposition (ALD), a chemical vapor deposition (CVD), and a simultaneous ordering of a slurry. 
     
     
         3 . The method of  claim 1 , wherein the step of forming a periodic three-dimensional structure comprises the steps of:
 forming a master comprising a plurality of photoresist patterns on a first substrate, the photoresist patterns having a predetermined height, width and space;   forming an elastomer on the master;   curing the elastomer, and separating the cured elastomer from the master to form a template;   filling troughs of the template with a polymer material, and curing the polymer material by contacting the template with a second substrate;   removing the template from the second substrate to form a first polymer layer; and   repeating the filling of the troughs of the template with the polymer material, the curing of the polymer material and the removing of the template from the second substrate, to thereby form at least one nth polymer layer on an (n−1) th  polymer layer, wherein the nth polymer layer is rotated by 90° with respect to the (n−1) th  polymer layer, and shifted in parallel by half the space with respect an (n−2) th  polymer layer, where n is a positive integer greater than 1.   
     
     
         4 . The method of  claim 1 , wherein the second material having the second refractive index comprises at least one of an oxide layer, a nitride layer, a sulfide layer, a composite layer, an atomic layer, SiC or TiC. 
     
     
         5 . The method of  claim 4 , wherein the oxide layer comprises at least one of Y 2 O 3 , MgO, Al 2 O 3 , LiNbO 3 , SrTiO 3 , BaTiO 3 , SiO 2  or TiO 2 . 
     
     
         6 . The method of  claim 4 , wherein the nitride layer comprises at least one of Si 3 N 4 , TiN or VN. 
     
     
         7 . The method of  claim 4 , wherein the composite layer comprises at least one of InAs, InP or GaAs. 
     
     
         8 . The method of  claim 4 , wherein the sulfide layer comprises ZnS. 
     
     
         9 . The method of  claim 4 , wherein the atomic layer comprises at least one of Se, Au, Ta, W, Nb, Pt or Fe. 
     
     
         10 . The method of  claim 4 , wherein the first material having the first refractive index comprises at least one of polyurethane, Si, SiO 2 , or Al 2 O 3 . 
     
     
         11 . The method of  claim 1 , wherein the step of conformally depositing exposed surfaces of the periodic three-dimensional structure with the second material having the second refractive index greater than the first refractive index comprises the step of conformally depositing exposed surfaces of the periodic three-dimensional structure with TiO 2  by using atomic layer deposition (ALD). 
     
     
         12 . The method of  claim 11 , wherein the step of conformally depositing exposed surfaces of the periodic three-dimensional structure with TiO 2  by using atomic layer deposition comprises the steps of:
 supplying a Ti precursor for the second material having the second refractive index into a reaction chamber receiving the periodic three-dimensional structure at a temperature   ranging from approximately 50° C. to approximately 150° C., to coat the periodic three-dimensional structure with the Ti precursor;
 supplying inert gas into the reaction chamber to purge the reaction chamber; 
 supplying an oxygen precursor into the reaction chamber to form TiO 2  on the periodic three-dimensional structure through chemical reaction of the Ti precursor and the oxygen precursor; and 
 supplying inert gas into the reaction chamber to purge the reaction chamber. 
   
     
     
         13 . The method of  claim 3 , wherein the step of filling troughs of the template with a polymer material comprises the step of filling troughs of the template with polyurethane. 
     
     
         14 . The method of  claim 3 , wherein the step of filling troughs of the template with a polymer material comprises the step of filling troughs of the template with at least one of Si, SiO 2  or Al 2 O 3 . 
     
     
         15 . A photonic crystal with a photonic bandgap produced by the method of  claim 1 .