Optical filter including a high refractive index material

Abstract

An optical filter including at least one of a high refractive index material and a low refractive index material; wherein the optical filter exhibits a reduced angle shift in at least one of a visible, near infrared, and an extreme ultraviolet wavelength is disclosed. A method of depositing a film is also disclosed.

We claim: 
     
         1 . An optical filter comprising:
 at least one of a high refractive index material and a low refractive index material;   wherein the optical filter exhibits a reduced angle shift in at least one of a visible, near infrared, and an extreme ultraviolet wavelength.   
     
     
         2 . The optical filter of  claim 1 , wherein the high refractive index material is silicon carbide having a refractive index of about 2.66. 
     
     
         3 . The optical filter of  claim 1 , wherein the high refractive index material is selected from TiO 2 , Nb 2 O 5 , SiC, Ta 2 O 5 , and combinations thereof. 
     
     
         4 . The optical filter of  claim 1 , wherein the low refractive index material is selected from SiO 2 , MgF, Al 2 O 3 , and combinations thereof. 
     
     
         5 . The optical filter of  claim 1 , wherein the optical filter includes at least one layer, wherein a thickness of the optical filter is less than about 10 μm. 
     
     
         6 . A method for depositing a film comprising:
 introducing, to a process chamber of a cathode sputter-deposition system, a first target including a high refractive index material;   introducing at least one of argon gas and hydrogen gas into the process chamber; and   depositing particles created from the first target onto a substrate to form a film,   wherein the film exhibits increased transmission of light in at least one of the visible and near infrared wavelengths.   
     
     
         7 . The method of  claim 6 , wherein the film exhibits increased transmission of light in the visible wavelength. 
     
     
         8 . The method of  claim 6 , wherein argon gas is the only gas introduced into the process chamber. 
     
     
         9 . The method of  claim 6 , wherein hydrogen gas is the only gas introduced into the process chamber. 
     
     
         10 . The method of  claim 6 , wherein both argon gas and hydrogen gas are introduced into the process chamber. 
     
     
         11 . The method of  claim 6 , further comprising introducing into the process chamber a second target including silicon. 
     
     
         12 . The method of  claim 6 , further comprising tilting a cathode exchanger in the cathode sputter-deposition system to a tilt angle selected from the group consisting of 30°, 35°, 40°, and 45°. 
     
     
         13 . The method of  claim 12 , wherein tilting the cathode exchanger to a tilt angle ranging from 0° C. to about 30° C. increases light transmission of the film. 
     
     
         14 . The method of  claim 6 , wherein the hydrogen gas was introduced in an amount ranging from about 0 SCCM to about 100 SCCM. 
     
     
         15 . The method of  claim 6 , further comprising annealing the film to the substrate. 
     
     
         16 . The method of  claim 15 , wherein the annealed film exhibits increased transmission of light in the near infrared wavelength. 
     
     
         17 . The method of  claim 6 , wherein a thickness of the film is reduced the higher the refractive index of the material. 
     
     
         18 . The method of  claim 6 , wherein the high refractive index material is selected from TiO 2 , Nb 2 O 5 , SiC, Ta 2 O 5 , and combinations thereof. 
     
     
         19 . The method of  claim 18 , wherein the high refractive index material is silicon carbide. 
     
     
         20 . The method of  claim 6 , wherein the cathode sputter-deposition system includes a first target of silicon carbide, a second target of silicon, introduced hydrogen gas, and a cathode exchanger tilt angle ranging from about 0° C. to about 30° C.