Formation of angled gratings

Abstract

Systems and methods discussed herein can be used to form gratings at various slant angles across a grating material on a single substrate by determining an ion beam angle and changing the angle of an ion beam among and between ion beam angles to form gratings with varying angles and cross-sectional geometries. The substrate can be rotated around a central axis, and one or more process parameters, such as a duty cycle of the ion beam, can be modulated to form a grating with a depth gradient.

1 . An optical device, comprising:
 a grating material layer, comprising:
 a first grating in the grating material layer, wherein the first grating comprises a first plurality of fins having a first slant angle, a first shape vector, and a first grating vector, wherein a direction of the first shape vector is in the direction from a first side of the first grating to a second side of the first grating, wherein the second side is opposite the first side and a first transitional surface extends between the first side and the second side; and 
 a second grating in the grating material layer, wherein the second grating comprises a second plurality of fins having a second slant angle, second shape vector and a second grating vector, wherein a direction of the second shape vector is in the direction from a first side of the first grating to a second side of the second grating, wherein the second side is opposite the first side and a second transitional surface extends between the first side and the second side, and wherein the second slant angle is different than the first slant angle and the second grating vector is different that the first grating vector. 
   
     
     
         2 . The optical device of  claim 1 , wherein the second shape vector is different than the first shape vector, and wherein the second transitional surface is different from the first transitional surface. 
     
     
         3 . The optical device of  claim 1 , wherein the material layer is composed of at least one of silicon oxycarbide, titanium oxide, titanium dioxide, silicon oxide, silicon dioxide, vanadium (IV) oxide, aluminum oxide, indium tin oxide, zinc oxide, tantalum pentoxide, silicon nitride, titanium nitride, zirconium dioxide, or oxynitrides. 
     
     
         4 . The optical device of  claim 1 , wherein the first transitional surface increases in depth from the first side and the second side. 
     
     
         5 . The optical device of  claim 1 , wherein the first plurality of fins or the second plurality of fins has a coating formed thereon. 
     
     
         6 . The optical device of  claim 5 , wherein the coating includes one or more layers of oxide. 
     
     
         7 . The optical device of  claim 1 , wherein the first plurality of fins or the second plurality of fins has a conformal coating formed thereon. 
     
     
         8 . An optical device, comprising:
 a substrate;   a grating material layer disposed on the substrate comprising:
 a first grating in the grating material layer, wherein the first grating comprises a first plurality of fins having a first slant angle, a first shape vector and a first grating vector, wherein a direction of the first shape vector is in the direction from a first side of the first grating to a second side of the first grating, wherein the second side is opposite the first side and a first transitional surface extends between the first side and the second side; and 
 a second grating in the material layer, wherein the second grating comprises a second plurality of fins having a second slant angle, a second shape vector and a second grating vector, wherein a direction of the second shape vector is in the direction from a first side of the first grating to a second side of the second grating, wherein the second side is opposite the first side and a second transitional surface extends between the first side and the second side, and wherein the second slant angle is different than the first slant angle and the second grating vector is different that the first grating vector. 
   
     
     
         9 . The optical device of  claim 8 , wherein the second shape vector is different than the first shape vector, and wherein the second transitional surface is different from the first transitional surface. 
     
     
         10 . The optical device of  claim 8 , wherein the grating material layer is composed of at least one of silicon oxycarbide, titanium oxide, titanium dioxide, silicon oxide, silicon dioxide, vanadium (IV) oxide, aluminum oxide, indium tin oxide, zinc oxide, tantalum pentoxide, silicon nitride, titanium nitride, zirconium dioxide, or oxynitrides. 
     
     
         11 . The optical device of  claim 8 , wherein the first transitional surface increases in depth from the first side and the second side. 
     
     
         12 . The optical device of  claim 8 , wherein the first plurality of fins or the second plurality of fins has a coating formed thereon. 
     
     
         13 . The optical device of  claim 12 , wherein the coating includes one or more layers of oxide. 
     
     
         14 . The optical device of  claim 8 , wherein the first plurality of fins or the second plurality of fins has a conformal coating formed thereon. 
     
     
         15 . An optical device, comprising:
 a first grating material layer disposed on a substrate, the first grating material layer having a wedge angle from a top surface of the first grating material layer to the substrate; and   a second grating material layer disposed over the first grating material layer, the second grating material layer comprising:
 a first grating formed on the substrate, wherein the first grating comprises a first plurality of fins having a first slant angle, a first shape vector and a first grating vector, wherein a direction of the first shape vector is in the direction from a first side of the first grating to a second side of the first grating, wherein the second side is opposite the first side and a first transitional surface extends between the first side and the second side; and 
 a second grating formed on the substrate, wherein the second grating comprises a second plurality of fins having a second slant angle, a second shape vector and a second grating vector, wherein a direction of the second shape vector is in the direction from a first side of the first grating to a second side of the second grating, wherein the second side is opposite the first side and a second transitional surface extends between the first side and the second side. 
   
     
     
         16 . The optical device of  claim 15 , wherein the first slant angle is different than the second slant angle, wherein the second shape vector is different than the first shape vector, wherein the second grating vector is different than the first grating vector, and wherein the second transitional surface is different from the first transitional surface. 
     
     
         17 . The optical device of  claim 15 , wherein the first grating or the second grating is composed of at least one of silicon oxycarbide, titanium oxide, titanium dioxide, silicon oxide, silicon dioxide, vanadium (IV) oxide, aluminum oxide, indium tin oxide, zinc oxide, tantalum pentoxide, silicon nitride, titanium nitride, zirconium dioxide, or oxynitrides. 
     
     
         18 . The optical device of  claim 15 , wherein the first transitional surface increases in depth from the first side and the second side. 
     
     
         19 . The optical device of  claim 15 , wherein the first plurality of fins or the second plurality of fins has a coating formed thereon. 
     
     
         20 . The optical device of  claim 19 , wherein the coating includes one or more layers of oxide.