Optical films and methods of making the same

1 . A method, comprising:

providing an article that includes a layer of a first material, wherein the layer of the first material includes at least one trench and wherein the layer is birefringent for light of wavelength λ propagating through the layer along an axis, wherein λ is between 150 nm and 2,000 nm; and

filling at least about 50% of a volume of the trench by sequentially forming a plurality of monolayers of a second material within the trench.

2 . The method of claim 1 , wherein the filling further comprises forming one or more monolayers of a third material within the trench, wherein the second and third materials are different.

3 . The method of claim 2 , wherein the monolayers of the second and third materials form a nanolaminate material.

4 . The method of claim 1 , wherein at least about 80% of the volume of the trench is filled by sequentially forming the plurality of monolayers of the second material within the trench.

5 . The method of claim 1 , wherein at least about 90% of the volume of the trench is filled by sequentially forming the plurality of monolayers of the second material within the trench.

6 . The method of claim 1 , wherein at least about 99% of the volume of the trench is filled by sequentially forming the plurality of monolayers of the second material within the trench.

7 . The method of claim 1 , wherein the second material is different from the first material.

8 . The method of claim 1 , wherein the layer of the first material and the second material form a continuous layer.

9 . The method of claim 1 , wherein the article comprises additional trenches formed in the surface of the layer of the first material.

10 . The method of claim 9 , wherein the method further comprises filling at least about 50% of a volume of each of the additional trenches by sequentially forming a plurality of monolayers of the second material within the additional trenches.

11 . The method of claim 9 , wherein the method further comprises filling at least about 80% of a volume of each of the additional trenches by sequentially forming a plurality of monolayers of the second material within the additional trenches.

12 . The method of claim 9 , wherein the method further comprises filling at least about 90% of a volume of each of the additional trenches by sequentially forming a plurality of monolayers of the second material within the additional trenches.

13 . The method of claim 9 , wherein the method further comprises filling at least about 99% of a volume of each of the additional trenches by sequentially forming a plurality of monolayers of the second material within the additional trenches.

14 . The method of claim 9 , wherein the trenches are separated by rows of the first material.

15 . The method of claim 7 , wherein the layer of the first material forms a surface relief grating.

16 . The method of claim 15 , wherein the surface relief grating has a grating period of about 500 nm or less.

17 . The method of claim 7 , wherein the trench is formed by etching a continuous layer of the first material.

18 . The method of claim 17 , wherein the etching comprising reactive ion etching.

19 . The method of claim 1 , wherein the trench is formed lithographically.

20 . The method of claim 19 , wherein the trench is formed using nano-imprint lithography.

21 . The method of claim 20 , wherein the nano-imprint lithography includes forming a pattern in a thermoplastic material.

22 . The method of claim 20 , wherein the nano-imprint lithography includes forming a pattern in a UV curable material.

23 . The method of claim 19 , wherein the trench is formed using holographic lithography.

24 . The method of claim 1 , further comprising forming a layer of the second material over the filled trench by sequentially forming monolayers of the second material over the trench.

25 . The method of claim 24 , wherein the layer of the second material has a surface with an arithmetic mean roughness of about 50 nm or less.

26 . The method of claim 1 , wherein the second material is a dielectric material.

27 . The method of claim 1 , wherein forming the plurality of monolayers of the second material comprises depositing a monolayer of a precursor and exposing the monolayer of the precursor to a reagent to provide a monolayer of the second material.

28 . The method of claim 27 , wherein the reagent chemically reacts with the precursor to form the second material.

29 . The method of claim 28 , wherein the reagent oxidizes the precursor to form the second material.

30 . The method of claim 27 , wherein depositing the monolayer of the precursor comprises introducing a first gas comprising the precursor into a chamber housing the article.

31 . The method of claim 30 , wherein a pressure of the first gas in the chamber is about 0.01 to about 100 Torr while the monolayer of the precursor is deposited.

32 . The method of claim 30 , wherein exposing the monolayer of the precursor to the reagent comprises introducing a second gas comprising the reagent into the chamber.

33 . The method of claim 30 , wherein a pressure of the second gas in the chamber is about 0.01 to about 100 Torr while the monolayer of the precursor is exposed to the reagent.

34 . The method of claim 30 , wherein a third gas is introduced into the chamber after the first gas is introduced and prior to introducing the second gas.

35 . The method of claim 27 , wherein the third gas is inert with respect to the precursor.

36 . The method of claim 27 , wherein the third gas comprises at least one gas selected from the group consisting of helium, argon, nitrogen, neon, krypton, and xenon.

37 . The method of claim 27 , wherein the precursor is selected from the group consisting of tris(tert-butoxy)silanol, (CH 3 ) 3 Al, TiCl 4 , SiCl 4 , SiH 2 Cl 2 , TaCl 3 , AlCl 3 , Hf-ethaoxide and Ta-ethaoxide.

38 . The method of claim 1 , wherein the trench has a width of about 1,000 nm or less.

39 . The method of claim 1 , wherein the trench has a depth of about 10 nm or more.

40 . The method of claim 8 , wherein the continuous layer is birefringent for light of wavelength λ propagating through the continuous layer along an axis, wherein λ is between 150 nm and 2,000 nm.

41 . A method, comprising:

forming a layer of a material on a surface of a grating using atomic layer deposition.

42 . The method of claim 41 , wherein the grating is a surface relief grating.

43 . The method of claim 41 , wherein the grating has a grating period of about 2,000 nm or less.

44 . The method of claim 1 , further comprising forming a second birefringent layer on the layer of the first material after filling the trench.

45 . The method of claim 44 , wherein the second birefringent layer comprises a plurality of trenches and forming the second birefringent layer includes filling the plurality of trenches by sequentially forming a plurality of monolayers of a third material within the trenches of the second birefringent layer.

46 . The method of claim 44 , further comprising forming additional birefringent layers on the second birefringent layer.

47 . A method, comprising:

forming an optical retardation film using atomic layer deposition.

48 . The method of claim 47 , wherein the optical retardation film is form birefringent.

49 . An article, comprising:

a continuous layer including rows of a first material alternating with rows of a nanolaminate material,

wherein the continuous layer is birefringent for light of wavelength λ propagating through the continuous layer along an axis, wherein λ is between 150 nm and 2,000 nm.

50 . The article of claim 49 , further comprising at least one antireflection film, wherein a surface of the article comprises a surface of the antireflection film.

51 . The article of claim 49 , further comprising a layer of a third material adjacent the continuous layer.

52 . The article of claim 49 , further comprising a layer of the nanolaminate material adjacent the continuous layer.

53 . The article of claim 49 , wherein the layer of the nanolaminate material adjacent the continuous layer has a surface with an arithmetic mean roughness of about 50 nm or less.

54 . The method of claim 49 , wherein the layer of the nanolaminate material adjacent the continuous layer has a surface with an arithmetic mean roughness of about 20 nm or less.

55 . The method of claim 49 , wherein the layer of the nanolaminate material adjacent the continuous layer has a surface with an arithmetic mean roughness of about 10 nm or less.

56 . The article of claim 49 , wherein the nanolaminate material has a refractive index of about 1.3 or more at λ.

57 . The article of claim 49 , wherein the nanolaminate material has a refractive index of about 1.5 or more at λ.

58 . The article of claim 49 , wherein the nanolaminate material has a refractive index of about 1.6 or more at λ.

59 . The article of claim 49 , wherein the nanolaminate material has a refractive index of about 1.7 or more at λ.

60 . The article of claim 49 , wherein the nanolaminate material has a refractive index of about 1.8 or more at λ.

61 . The article of claim 49 , wherein the nanolaminate material has a refractive index of about 1.9 or more at λ.

62 . The article of claim 49 , wherein the nanolaminate material has a refractive index of about 2.0 or more at λ.

63 . The article of claim 49 , wherein the nanolaminate material comprises portions of a second material and portions of a third material, wherein the second and third materials are different.

64 . The article of claim 63 , wherein the first and third materials are the same.

65 . The article of claim 49 , wherein the nanolaminate material comprises a dielectric material.

66 . The article of claim 49 , wherein the nanolaminate material comprises an inorganic material.

67 . The article of claim 49 , wherein the nanolaminate material comprises a metal.

68 . The article of claim 49 , wherein the nanolaminate material comprises a material selected from a group consisting of SiO 2 , SiN x , Si, Al 2 O 3 , ZrO 2 , Ta 2 O 5 , TiO 2 , HfO 2 , Nb 2 O 5 , and MgF 2 .

69 . The article of claim 49 , wherein the first material is a dielectric material.

70 . The article of claim 49 , wherein the first material is an inorganic material.

71 . The article of claim 49 , wherein the first material is a polymer.

72 . The article of claim 49 , wherein the first material is a semiconductor.

73 . The article of claim 49 , wherein the first material is a metal.

74 . The article of claim 49 , wherein the first material is selected from a group consisting of SiO 2 , SiN x , Si, Al 2 O 3 , ZrO 2 , Ta 2 O 5 , TiO 2 , HfO 2 , Nb 2 O 5 , and MgF 2 .

75 . The article of claim 49 , wherein the first material is a glass.

76 . The article of claim 49 , wherein the continuous layer forms a grating with a grating period of about 500 nm or less.

77 . The article of claim 49 , wherein the continuous layer forms a grating with a grating period of about 200 nm or less.

78 . The article of claim 49 , wherein the continuous layer forms a grating with a grating period of about 100 nm or less.

79 . The article of claim 49 , wherein the continuous layer forms a grating with a grating period of about 50 nm or less.

80 . The article of claim 49 , wherein the rows of the first material have a minimum width of about 500 nm or less.

81 . The article of claim 49 , wherein the rows of the first material have a minimum width of about 200 nm or less.

82 . The article of claim 49 , wherein the rows of the first material have a minimum width of about 100 nm or less.

83 . The article of claim 49 , wherein the rows of the first material have a minimum width of about 50 nm or less.

84 . The article of claim 49 , wherein the rows of the first material have a minimum width of about 20 nm or less.

85 . The article of claim 49 , wherein the rows of the first material have a minimum width of about 10 nm or less.

86 . The article of claim 49 , wherein the rows of the first material have a minimum width that is different than a minimum width of the rows of the nanolaminate material.

87 . The article of claim 49 , wherein the rows of the first material have a minimum width that is the same as a minimum width of the rows of the nanolaminate material.

88 . The article of claim 49 , wherein a minimum width of each of the rows of the first material is substantially the same.

89 . The article of claim 49 , wherein a minimum width of each of the rows of the nanolaminate material is substantially the same.

90 . The article of claim 49 , wherein the continuous layer has a thickness of about 15 nm or more.

91 . The article of claim 49 , wherein the continuous layer has a thickness of about 100 nm or more.

92 . The article of claim 49 , wherein the continuous layer has a thickness of about 200 nm or more.

93 . The article of claim 49 , wherein the continuous layer has a thickness of about 300 nm or more.

94 . The article of claim 49 , wherein the continuous layer has a thickness of about 500 nm or more.

95 . The article of claim 49 , wherein the continuous layer has a thickness of about 1,000 nm or more.

96 . The article of claim 49 , wherein the continuous layer has a thickness of about 1,500 nm or more.

97 . The article of claim 49 , wherein the layer has a thickness of about 2,000 nm or more.

98 . The article of claim 49 , wherein the continuous layer has an optical retardation of about 1 nm or more for light of wavelength λ propagating through the continuous layer along an axis, wherein λ is between 150 nm and 2,000 nm.

99 . The article of claim 49 , wherein the continuous layer has an optical retardation of about 2 nm or more for light of wavelength λ propagating through the continuous layer along an axis, wherein λ is between 150 nm and 2,000 nm.

100 . The article of claim 49 , wherein the continuous layer has an optical retardation of about 5 nm or more for light of wavelength λ propagating through the continuous layer along an axis, wherein λ is between 150 nm and 2,000 mm.

101 . The article of claim 49 , wherein the layer has an optical retardation of about 10 nm or more for light of wavelength λ propagating through the composite layer along an axis, wherein λ is between 150=n and 2,000 nm.

102 . The article of claim 49 , wherein the layer has an optical retardation of about 20 nm or more for light of wavelength λ propagating through the composite layer along an axis, wherein λ is between about 150 nm and about 2,000 nm.

103 . The article of claim 49 , wherein the layer has an optical retardation of about 50 nm or more for light of wavelength λ propagating through the composite layer along an axis, wherein λ is between about 150 nm and about 2,000 nm.

104 . The article of claim 49 , wherein the layer has an optical retardation of about 2,000 nm or less for light of wavelength λ propagating through the composite layer along an axis, wherein λ is between about 150 nm and about 2,000 nm.

105 . The article of claim 49 , wherein the layer has an optical retardation of about 1,000 nm or less for light of wavelength λ propagating through the composite layer along an axis, wherein λ is between about 150 nm and about 2,000 mm.

106 . The article of claim 49 , wherein λ is between about 400 nm and about 700 nm.

107 . The article of claim 49 , wherein λ is between about 510 nm and about 570 mm.

108 . The article of claim 49 , wherein the continuous layer has an optical retardation of about 4 nm or more for light of wavelength λ propagating through the continuous layer along an axis, wherein λ is between about 400 nm and about 700 nm.

109 . The article of claim 49 , further comprising a second continuous layer including rows of a third material alternating with rows of a second nanolaminate material,

wherein the second continuous layer is birefringent for light of wavelength λ propagating through the second continuous layer along the axis.

110 . The article of claim 109 , further comprising additional form birefringent layers, wherein each of the form birefringent layers are birefringent for light of wavelength λ propagating through each form birefringent layer along the axis.

111 . An article, comprising:

a form birefringent optical retardation film comprising a nanolaminate material.