CN100476464C - Optical films and methods of making the same - Google Patents

Abstract

Films for optical use, articles containing such films, methods for making such films, and systems that utilize such films, are disclosed.

Description

Blooming and manufacture method thereof

Technical field

The present invention relates to a kind of blooming and correlated product, System and method for.

Background technology

Optical device and optical system needing in the application of control light to be generally used for.The example of optical device comprises lens, polarizer, light filter, antireflecting film, delayer (for example quarter-wave plate) and beam splitter (for example polarization and unpolarized beam splitter).

Summary of the invention

The present invention relates to a kind of optical film, comprise the goods of this film, make the method for this film, and the system that adopts this film.

Aspect first, feature of the present invention is a kind of method, comprise: a kind of goods are provided, comprise first material layer, wherein first material layer comprises at least one groove, and described layer is for propagating the only birefringent of wavelength X by this layer along axle, and wherein λ between the 2000nm, and fills the volume of described groove about at least 50% at 150nm by the individual layer that forms a plurality of second materials in this groove successively.

On the other hand, feature of the present invention is a kind of method, comprising: form layer of material with atomic layer deposition on grid surface.

On the other hand, feature of the present invention is a kind of method, comprising: form the optical delay film with atomic layer deposition.

On the other hand, feature of the present invention is a kind of goods, described comprising: comprise and the capable capable successive layers of first material that replaces of nanometer multilayer compound substance that wherein said successive layers is for propagating the only birefringent of wavelength X by successive layers along axle, wherein λ at 150nm between the 2000nm.

On the other hand, feature of the present invention is a kind of goods, comprising: the structural birefringence optical delay film that comprises the nanometer multilayer compound substance.

Embodiments of the invention can comprise one or several in the following feature.

Described filling can further be included in the individual layer that forms one or more the 3rd materials in the described groove, and wherein said second is different with the 3rd material.Described second and the individual layer of the 3rd material can form the nanometer multilayer compound substance.Fill about at least 80% (for example, about at least 90%, about at least 99%) of the volume of described groove by the individual layer that in described groove, forms a plurality of second materials successively.Described second material can be different with described first material.Described first material and described second material layer can form successive layers.Described successive layers can be birefringence for the light of propagating the wavelength X by this successive layers along axle, wherein λ at 150nm between the 2000nm.Described goods can be included in the extra groove that forms in the surface of described first material layer.Described method can further comprise by the individual layer that in described extra groove, forms a plurality of second materials successively fill each described extra groove volume about at least 50%.Wherein said method can further comprise about at least 80% (for example, about at least 90%, about at least 99%) of filling the volume of each described extra groove by the individual layer that forms a plurality of second materials in described extra groove successively.Described groove can be by the capable separation of described first material.Described first material layer can form concave-convex surface grid (surface relief grating).Described concave-convex surface grid can have the pitch of about 500nm or littler (for example, about 400nm or littler, approximately 300nm or littler, approximately 200nm or littler, approximately 100nm or littler).

Described groove can be formed by the successive layers of described first material of etching (for example, reactive ion etching).Described groove can form with mint-mark.For example, described groove can form with nano impression lithography or holographic lithography.When described groove formed with the nano impression lithography, described nano impression lithography can be included in and form pattern on the thermoplastic.Alternatively, or extraly, described nano impression lithography can be included on the UV curing materials and form pattern.

Described method can further comprise: by forming second material layer above the groove that is being filled forming the individual layer of second material successively above the groove.Described second material layer can have the surface of the arithmetic average roughness of about 50nm or littler (for example, about 40nm or littler, approximately 30nm or littler, approximately 20nm or littler, approximately 10nm or littler).

Described second material can be dielectric material.In certain embodiments, the described a plurality of individual layers that form described second material comprise the individual layer of deposit parent and the individual layer of parent are exposed to reactant, so that the individual layer of described second material to be provided.Described reactant and described parent chemical reaction are to form described second material.For example, the oxidable described parent of described reactant is to form described second material.The individual layer of deposit parent can comprise will comprise first gas of described parent import and hold in the chamber of goods.During the individual layer of deposit parent, the pressure of first gas can be about 0.01 to about 100Torr in the chamber.The individual layer of described parent is exposed to described reactant, and to comprise that second gas that will comprise described reactant imports described indoor.When the individual layer of described parent was exposed to described reactant, the pressure of second gas can be about 0.01 to about 100Torr in the chamber.Import after described first gas, import before described second gas, the 3rd gas can be imported described indoor.Described the 3rd gas can be inertia for described parent.Described the 3rd gas comprises at least a gas of selecting from the group of being made of helium, argon gas, nitrogen, neon, krypton gas and xenon.Described parent can be from by 3-tert-butoxy silanol, (CH ₃) ₃Al, TiCl ₄, SiCl ₄, SiH ₂Cl ₂, TaCl ₃, AlCl ₃, select in the group that Hf-ethaoxide and Ta-ethaoxide form.

The width of described groove can be about 1000nm or littler (for example, about 900nm or littler, approximately 800nm or littler, about 700nm or littler, approximately 600nm or littler, approximately 500nm or littler, about 400nm or littler, approximately 300nm or littler, approximately 200nm or littler).The degree of depth of described groove can be about 10nm or more (for example, about 20nm or more, approximately 30nm or more, about 40nm or more, approximately 50nm or more, approximately 75nm or more, about 100nm or more, approximately 150nm or more, approximately 200nm or more, about 300nm or more, about 400nm or more, approximately 500nm or more, approximately 1000nm or more, about 1500nm or more, approximately 2000nm or more).

This method forms second birefringent layers after can further being included in and filling described groove on described first material layer.Described second birefringent layers can comprise a plurality of grooves, and forms described second birefringent layers and comprise by the individual layer that forms a plurality of the 3rd materials in the groove of described second birefringent layers successively and fill described a plurality of groove.This method also can be included in the extra birefringent layers of formation on described second birefringent layers.

In a particular embodiment, described grid can be the concave-convex surface grid.The grid distance of described grid can be about 2000nm or littler (for example, about 1500nm or littler, about 1000nm or littler, about 750nm or littler, about 500nm or littler, about 300nm or littler, about 200nm or littler).

Described optics deposited film can be structural birefringence.

Described goods can further comprise at least one antireflecting film, and wherein said product surface comprises described antireflecting film surface.In certain embodiments, described goods also can comprise three material layer adjacent with described successive layers.Described goods also can comprise the described nanometer multilayer composite layer adjacent with described successive layers.The described nanometer multilayer composite layer adjacent with described successive layers can have the surface of the 50nm of being approximately or littler (for example, about 40nm or littler, approximately 30nm or littler, approximately 20nm or littler, approximately 10nm or littler) arithmetic average roughness.Described nanometer multilayer compound substance can have about 1.3 or bigger refractive index (for example, about 1.4 or bigger, about 1.5 or bigger at λ, about 1.6 or bigger, about 1.7 or bigger, about 1.8 or bigger, about 1.9 or bigger, about 2.0 or bigger, about 2.1 or bigger).Described first material can have about 1.3 or bigger refractive index (for example, about 1.4 or bigger, about 1.5 or bigger at λ, about 1.6 or bigger, about 1.7 or bigger, about 1.8 or bigger, about 1.9 or bigger, about 2.0 or bigger, about 2.1 or bigger).Described nanometer multilayer compound substance can comprise the ingredient of second material and the ingredient of the 3rd material, and wherein said second material is different with the 3rd material.In certain embodiments, described first material is identical with the 3rd material.

Described nanometer multilayer compound substance can comprise dielectric material, inorganic material and/or metal.Described nanometer multilayer compound substance can comprise from by SiO ₂, SiN _x, Si, Al ₂O ₃, ZrO ₂, Ta ₂O ₅, TiO ₂, HfO ₂, Nb ₂O ₅And MgF ₂A kind of material of selecting in the group of forming.

Described first material can be dielectric material, inorganic material, glass, polymkeric substance, semiconductor and/or metal.In certain embodiments, described first material is from by SiO ₂, SiN _x, Si, Al ₂O ₃, ZrO ₂, Ta ₂O ₅, TiO ₂, HfO ₂, Nb ₂O ₅And MgF ₂Select in the group of forming.

Described successive layers can form the grid that grid distance is approximately 500nm or littler (for example, about 200nm or littler, approximately 100nm or littler, approximately 50nm or littler).The capable minimum widith of described first material with about 500nm or littler (for example, about 200nm or littler, approximately 100nm or littler, approximately 50nm or littler, approximately 20nm or littler, approximately 10nm or littler).Described first material is capable to have the minimum widith identical or different minimum widith capable with described nanometer multilayer compound substance.The minimum widith that each first material is capable can be roughly the same.Alternatively, or extraly, the minimum widith that each nanometer multilayer compound substance is capable can be roughly the same.

The thickness of described successive layers can be about 15nm or bigger (for example, about 30nm or bigger, approximately 50nm or bigger, approximately 75nm or bigger, about 100nm or bigger, about 150nm or bigger, approximately 200nm or bigger, approximately 300nm or bigger, about 500nm or bigger, about 1000nm or bigger, approximately 1500nm or bigger, approximately 2000nm or bigger).In certain embodiments, described successive layers for the light of propagating the wavelength X by described successive layers along axle have about 1nm or more (for example, about 2nm or more, about 5nm or more, about 10nm or more, approximately 20nm or more, approximately 50nm or more) optical delay, wherein λ at 150nm between the 2000nm.Described successive layers has about 2000nm or littler optical delay for the light of propagating the wavelength X by described successive layers along axle, wherein λ at 200nm between the 2000nm.In certain embodiments, λ arrives between about 700nm at about 400nm and (for example, arrives between about 570nm at about 510nm).In certain embodiments, described successive layers has about 4nm or more optical delay for the light of propagating the wavelength X by described successive layers along axle, wherein λ at 400nm between the 700nm.

Described goods can comprise: second successive layers, comprise with capable the 3rd material that replaces of the second nanometer multilayer compound substance capablely, and wherein said second successive layers is for propagate the only birefringent of wavelength X by described second successive layers along axle.Described goods can further comprise: extra structural birefringence layer, wherein, each structural birefringence layer is only birefringent for the wavelength X of passing through each structural birefringence layer along the axle propagation.

Each embodiment of the present invention can comprise following one or more advantages.

In certain embodiments, goods can be more reliable optical delay, have high transmissivity and accurate control lag at required wavelength.Optical delay can comprise one or more structural birefringence layers.Structural birefringence is by arrange that in the mode that replaces the long structure of wavelet that at least two kinds of different materials (for example optically isotropic material) obtain realizes in medium.Structural birefringence can realize that in this structure, the refractive index of medium is periodically modulated by the long lattice structure of wavelet, and its cycle is roughly less than required wavelength.Because the cycle is less than required wavelength, essence has only zeroth order diffraction to take place, all high order diffractions all decay (for example, substantially all transmission and/or reflections of the light beam of required wavelength).Though the material of formed shape birefringent medium can be optically isotropic (that is, having isotropic refractive index), medium itself can be optically anisotropic, thus form dielectric grid.

In certain embodiments, optical delay can comprise for example opposed one or more structural birefringence layers that formed by continuous material, has the groove of being filled by gas (for example air) in the layer.Therefore, this optical delay can be than the more reliable mechanical property of optical delay with discontinuous layer (for example, comprising one or more layers of filling the groove of air).

In a particular embodiment, the aspect ratio of the width of the ingredient of each layer of continuous shape birefringent layers and thickness can be higher.As example, in layer, etch the groove of high aspect ratio, use conformal coating process (for example atomic layer deposition) filling groove subsequently, thereby the birefringent layers of the continuous shape with high aspect ratio is provided.

The birefringence of optical delay can be accurately controlled.For this reason, the refractive index of one or more ingredients of the structural birefringence layer of optical delay can for example assign to realize being converted to required numerical value by the one-tenth of controlling each ingredient, controls birefringence thus.For example, can be by cambial one or several ingredient of nanometer multilayer complex.The refractive index of nanometer multilayer complex can be regulated by the ratio of selecting two or more different materials in the nanometer multilayer complex, is forming under the situation of nanometer multilayer complex with atomic layer deposition, and this can control based on individual layer on individual layer.

Alternatively, or extraly, accurately the structure of key-course can accurately be controlled the birefraction of structural birefringence layer.For example, determine that with countermark technology (for example, electron beam lithography art, nano impression lithography, holographic lithography) structure (for example, the degree of depth, width and grid profile) of structural birefringence layer can realize the accurate control to structure.

In certain embodiments, can accurately control the delay of optical delay.For example, can accurately control the birefraction of the structural birefringence layer in the optical delay and/or the degree of depth so that required delay to be provided.For example, optical delay can comprise one or more layers, with the thickness of the ingredient (for example one or more etching stopping layer) of structural birefringence layer in the control optical delay.

In certain embodiments, optical delay has high permeability at required wavelength.For example, optical delay can comprise one or more antireflecting films on one or more interfaces, reduces the reflection of light of required wavelength.Alternatively, or extraly, the layer of optical delay can be formed by the material that has low relatively absorptivity at required wavelength.

Further feature of the present invention and advantage can and be described from accompanying drawing, and obvious in the accessory rights requirement.

Description of drawings

Fig. 1 is the skeleton view of the embodiment of optical delay.

Fig. 2 A-2J illustrates the manufacturing step of optical delay shown in Figure 1.

Fig. 3 is the synoptic diagram of atomic layer deposition system.

Fig. 4 illustrates the process flow diagram that adopts atomic layer deposition to form the step of nanometer multilayer complex (nanolaminate).

Fig. 5 is the cut-open view of another embodiment of optical delay.

Fig. 6 is the cut-open view of an embodiment that comprises the optical delay of a plurality of retardation layers.

Fig. 7 is the cut-open view that has the polarizer of optical delay.

Fig. 8 is the cut-open view that has the LCD of optical delay.

Fig. 9 A is a scanning electron micrograph of filling up the preceding long grid of wavelet of groove.

Fig. 9 B is the scanning electron micrograph of the long grid of wavelet shown in Fig. 9 A that fills up behind the groove.

Similar Reference numeral is represented similar element in institute's drawings attached.

Embodiment

With reference to Fig. 1, the embodiment of delayer 100 comprises: retardation layer 110 and two antireflecting films 150 and 160.Delayer 100 also comprises substrate 140, etching stopping layer 130 and overlayer 120.Retardation layer 110 is the form of grid, and comprises ingredient 111 with first refractive index and the ingredient 112 with second refractive index.Retardation layer 110 is only birefringent for the wavelength X of propagating along the axle 101 of the z axle that is parallel to cartesian coordinate system shown in Figure 1.Usually, λ arrives between about 5000nm at about 150nm.In certain embodiments, λ is corresponding to the wavelength in the visible light of the electromagnetic spectrum part (that is, from about 400nm to about 700nm).

Ingredient 111 and 112 extends along the y direction, forms the periodic structure of being made up of a series of row with different refractivity that replace.Row corresponding to ingredient 111 has width Λ on the x direction ₁₁₁, and on the x direction, have width Λ corresponding to the row of width 112 ₁₁₂The width of row is less than λ, make retardation layer 110 under the situation that can not produce remarkable high order diffraction for the light form dielectric grid of wavelength X.Refractive index and Λ according to the thickness of retardation layer 110, ingredient 111 and 112 ₁₁₁And Λ ₁₁₂, the light wave of different polarization state passes through retardation layer 110 with different phase shift state propagation.Therefore, can select these parameters and the delay of aequum is provided for the polarized light of wavelength X.

Retardation layer 110 has corresponding to n _e-n _oBirefringence n, n wherein _eAnd n _oBe respectively the extraordinary and the ordinary refractive index of retardation layer 110.For retardation layer 110, n _eAnd n _oAs follows by following formula respectively:

$n_o^2=\frac{{\mathrm{\&Lambda;}}_{111}}{{\mathrm{\&Lambda;}}_{111}+{\mathrm{\&Lambda;}}_{112}}{\mathrm{<figure-callout\; id="111"\; label="n"\; filenames="C20058001831700271.png,C20058001831700289.png"\; state="\{\{state\}\}">n</figure-callout>}}_{111}^2+\frac{{\mathrm{\&Lambda;}}_{112}}{{\mathrm{\&Lambda;}}_{111}+{\mathrm{\&Lambda;}}_{112}}{\mathrm{<figure-callout\; id="112"\; label="n"\; filenames="C20058001831700271.png,C20058001831700287.png"\; state="\{\{state\}\}">n</figure-callout>}}_{112}^2$

(1)

$\frac{1}{n_e^2}=\frac{{\mathrm{\&Lambda;}}_{111}}{{\mathrm{\&Lambda;}}_{111}+{\mathrm{\&Lambda;}}_{112}}\frac{1}{{\mathrm{<figure-callout\; id="111"\; label="n"\; filenames="C20058001831700271.png,C20058001831700289.png"\; state="\{\{state\}\}">n</figure-callout>}}_{111}^2}+\frac{{\mathrm{\&Lambda;}}_{111}}{{\mathrm{\&Lambda;}}_{111}+{\mathrm{\&Lambda;}}_{112}}\frac{1}{{\mathrm{<figure-callout\; id="112"\; label="n"\; filenames="C20058001831700271.png,C20058001831700287.png"\; state="\{\{state\}\}">n</figure-callout>}}_{112}^2}$

In equation (1), n ₁₁₁And n ₁₁₂And Λ ₁₁₁And Λ ₁₁₂Refer to the refractive index and the thickness (along the x direction) of ingredient 111 and 112 respectively.Usually, n _eAnd n _oValue depend on n ₁₁₁, n ₁₁₂, Λ ₁₁₁And Λ ₁₁₂, and at n ₁₁₁With n ₁₁₂Between.Can select Λ ₁₁₁And Λ ₁₁₂With according to the n that provides by equation (1) _cAnd n _oValue provides required Δ n value.In addition, refractive index n ₁₁₁With n ₁₁₂Based on ingredient 111 and 112 composition separately, can select n ₁₁₁With n ₁₁₂So that required Δ n value to be provided.In certain embodiments, Δ n relatively large (for example, about 0.1 or bigger, about 0.15 or bigger, about 0.2 or bigger, about 0.3 or bigger, about 0.5 or bigger, about 1.0 or bigger, about 1.5 or bigger, about 2.0 or bigger).Alternatively, in other embodiments, Δ n relatively large (for example, about 0.05 or littler, about 0.04 or littler, about 0.03 or littler, about 0.02 or littler, about 0.01 or littler, about 0.005 or littler, about 0.002 or littler, 0.001 or littler).

Usually, the refractive index of ingredient 111 can be about 1.3 or bigger by (for example, about 1.3 or bigger, about 1.4 or bigger, about 1.5 or bigger, about 1.6 or bigger, about 1.7 or bigger, about 1.8 or bigger, about 1.9 or bigger, about 2.0 or bigger, about 2.1 or bigger, about 2.2 or bigger).In addition, usually, the refractive index of ingredient 112 can be about 1.3 or bigger (for example, about 1.3 or bigger, about 1.4 or bigger, about 1.5 or bigger, about 1.6 or bigger, about 1.7 or bigger, about 1.8 or bigger, about 1.9 or bigger, about 2.0 or bigger, about 2.1 or bigger, about 2.2 or bigger).

Usually, Λ ₁₁₁Can be 0.2 λ or littler (for example, about 0.1 λ or littler, about 0.05 λ or littler, about 0.04 λ or littler, about 0.03 λ or littler, about 0.02 λ or littler, about 0.01 λ or littler).For example, in certain embodiments, Λ ₁₁₁Be about 200nm or littler (for example, about 150nm or littler, about 100nm or littler, about 80nm or littler, about 70nm or littler, about 60nm or littler, about 50nm or littler, about 40nm or littler, about 30nm or littler).Similarly, Λ 112 can be 0.2 λ or littler (for example, about 0.1 λ or littler, about 0.05 λ or littler, about 0.04 λ or littler, about 0.03 λ or littler, about 0.02 λ or littler, about 0.01 λ or littler).For example, in certain embodiments, Λ ₁₁₂Be about 200nm or littler (for example, about 150nm or littler, about 100nm or littler, about 80nm or littler, about 70nm or littler, about 60nm or littler, about 50nm or littler, about 40nm or littler, about 30nm or littler).Λ ₁₁₁And Λ ₁₁₂Can be same to each other or different to each other.

Along the x axle, the refractive index of retardation layer 110 is periodic, has corresponding to Λ ₁₁₁+ Λ ₁₁₂Periods lambda.Usually, Λ is less than λ, for example, for about 0.5 λ or littler (for example, about 0.3 λ or littler, about 0.2 λ or littler, about 0.1 λ or littler, about 0.08 λ or littler, about 0.05 Λ or littler, about 0.04 λ or littler, about 0.03 λ or littler, about 0.02 λ or littler, about 0.01 λ or littler).In certain embodiments, Λ is 500nm or littler (for example, about 300nm or littler, about 200nm or littler, about 100nm or littler, about 80nm or littler, about 60nm or littler, about 50nm or littler, about 40nm or littler).

Although shown in retardation layer 110 have 19 ingredients, usually, the quantity of the ingredient in the retardation layer can change as required.The quantity of ingredient depends on periods lambda, and the delayer final user uses required area.In certain embodiments, retardation layer 110 can have about 50 or more a plurality of ingredient (for example, about 100 or more a plurality of ingredient, about 500 or more a plurality of ingredient, about 1000 or more a plurality of ingredient, about 5000 or more a plurality of ingredient, about 10000 or more a plurality of ingredient, about 50000 or more a plurality of ingredient, about 100000 or more a plurality of ingredient, about 500000 or more a plurality of ingredient).

The thickness d of the retardation layer of measuring along the z axle 110 can change as required.Usually, based on the required delay and select the thickness of retardation layer 110 under wavelength X of the refractive index of ingredient 111 and 112 and retardation layer 110.In certain embodiments, d can be about 50nm or bigger (for example, about 75nm or bigger, about 100nm or bigger, about 125nm or bigger, approximately 150nm or bigger, approximately 200nm or bigger, about 250nm or bigger, about 300nm or bigger, approximately 400nm or bigger, approximately 500nm or bigger, about 1000nm or bigger, for example about 2000nm).

The aspect ratio d of retarder thickness compares Λ ₁₁₁And/or d compares Λ ₁₁₂Can be high relatively.D: Λ for example ₁₁₁And/or d: Λ ₁₁₂Can be about 2: 1 or higher (for example, about 3: 1 or higher, about 4: 1 or higher, about 5: 1 or higher, about 8: 1 or higher, about 10: 1 or higher).

The delay of retardation layer 110 is corresponding to the thickness of retardation layer 110 and the product of Δ n.By selecting suitable Δ n and layer thickness value, can change delay as required.In certain embodiments, the delay of retardation layer 110 can be about 50nm or more (for example, about 75nm or bigger, about 100nm or bigger, about 125nm or bigger, approximately 150nm or bigger, approximately 200nm or bigger, about 250nm or bigger, about 300nm or bigger, approximately 400nm or bigger, approximately 500nm or bigger, about 1000nm or bigger, for example about 2000nm).Alternatively, in other embodiments, postpone to be about 40nm or littler (for example, about 30nm or littler, approximately 20nm or littler, approximately 10nm or littler, approximately 5nm or littler, approximately 2nm or littler).In certain embodiments, postpone to be equivalent to λ/4 or λ/2.

Postpone also can be expressed as phase retardation Γ, wherein:

$\mathrm{\&Gamma;}=\frac{2\mathrm{\&pi;}}{\mathrm{\&lambda;}}\mathrm{\&Delta;nd}---\left(2\right)$

For example, quarter-wave postpones to be equivalent to Γ=pi/2, and 1/2nd ripples postpone to be equivalent to Γ=π.Usually, phase retardation can change as required.In certain embodiments, phase retardation can be about 2 π or littler (for example, about 0.8 π or littler, about 0.7 π or littler, about 0.6 π or littler, about 0.5 π or littler, about 0.4 π or littler, about 0.2 π or littler, about 0.2 π or littler, about 0.1 π or littler, about 0.05 π or littler, about 0.01 π or littler).Alternatively, in other embodiments, the phase retardation of retardation layer 110 can be more than 2 π (for example, about 3 π or more, about 4 π or more, about 5 π or more).

Usually, ingredient 111 and 112 composition can change as required.Ingredient 111 and/or 112 can comprise inorganic and/or organic material.The example of inorganic material comprises metal, semiconductor and Inorganic Dielectric Material (for example glass).The example of organic material comprises polymkeric substance.

In certain embodiments, ingredient 111 and/or ingredient 112 comprise one or more dielectric materials, and for example dielectric oxide (for example, metal oxide), fluoride (for example, metal fluoride), sulfide and/or nitride (for example, metal nitride).The example of oxide comprises: SiO ₂, Al ₂O ₃, Nb ₂O ₅, TiO ₂, ZrO ₂, HfO ₂, SnO ₂, ZnO, ErO ₂, Sc ₂O ₃And Ta ₂O ₅The example of fluoride comprises MgF ₂Other example comprises: ZnS, SiN _x, SiO _yN _x, AlN, TiN and HfN.

Ingredient 111 and 112 composition usually according to they optical property and they and be used to make the compatibility (compatibility) of technology of optical delay 100 and they and the compatibility of material that is used to form other layer of optical delay 100 are selected.Ingredient 111 and/or 112 composition may be selected to be in wavelength X has specific refractive index.Usually, ingredient 111 is different in the corresponding refractive index of wavelength X with ingredient 112.In certain embodiments, ingredient 111 forms by having relative high refractive index materials with ingredient 112, and refractive index was approximately 2.35 TiO when for example wavelength was 632nm ₂, refractive index was 2.15 Ta when perhaps wavelength was 632nm ₂O ₅Alternatively, ingredient 111 or ingredient 112 can be formed by the material with relative low-refraction.The example of low-index material comprises that refractive index when wavelength is 632nm is respectively 1.45 and 1.65 SiO ₂And Al ₂O ₃

In certain embodiments, the composition of ingredient 111 and/or ingredient 112 has low relatively absorptivity at λ, makes retardation layer 110 have low relatively absorptivity at λ.For example, retardation layer 110 can absorb about 5% or littler radiation (for example, about 3% or littler when wavelength X lower edge axle 101 is propagated, about 2% or littler, about 1% or littler, about 0.5% or littler, about 0.2% or littler, about 0.1% or littler).

Ingredient 111 and/or ingredient 112 can be formed by single kind material or multiple different materials.In certain embodiments, ingredient 111 and 112 one or two form by the nanometer multilayer compound substance, described nanometer multilayer compound substance refers to by at least two kinds of different material layers to be formed, and one of them plants material layer material of (for example, 1 to thick between about 10 individual layers (monolayer)) as thin as a wafer.On the optics, the nanometer multilayer compound substance has the refractive index of the local uniform that depends on its composition material refractive index.The amount that changes every kind of component material can change the refractive index of nanometer multilayer complex.The example of nanometer multilayer complex part comprises by SiO ₂Individual layer and TiO ₂Individual layer, SiO ₂Individual layer and Ta ₂O ₅Individual layer, perhaps Al ₂O ₃Individual layer and TiO ₂The part that individual layer is formed.

That ingredient 111 and/or ingredient 112 can comprise is crystalline, hemicrystalline and/or pars amorpha.Usually, amorphous materials is an optical isotropy, and the better printing opacity of the crystalline or most of crystalline part of comparable part.As an example, in certain embodiments, ingredient 111 and 112 is all formed by amorphous materials, for example amorphous dielectric material (for example, amorphous TiO ₂Or SiO ₂).Alternatively, in a particular embodiment, ingredient 111 forms (for example, crystalline or hemicrystalline Si) by crystalline or hemicrystalline material, and (for example amorphous dielectric material is as amorphous TiO and ingredient 112 is formed by amorphous materials ₂Or SiO ₂).

Referring now to other layer in the optical delay 100, usually, 140 pairs of optical delays 100 of substrate provide mechanical support.In a particular embodiment, 140 pairs of wavelength X of substrate only transparent, transmission incident most wavelength thereon be λ light (for example, about 90% or more, about 95% or more, about 97% or more, about 99% or more, about 99.5% or more).

Usually, substrate 140 can be formed by any material compatible with the manufacturing process of producing delayer 100 and that can support other layer.In certain embodiments, substrate 140 is made by glass, BK7 (sale of Abrisa company) for example, and borosilicate glass is (for example, the pyrex that Corning sells), alumina silicate glass (for example, the C1737 that Corning sells), perhaps quartz/fused quartz (fused silica), in certain embodiments, substrate 140 can be formed by crystalline material, for example nonlinear optical crystal (for example, LiNbO ₃Or magneto-optic turn (magneto-optical rotator), for example garnett) or crystalline (or hemicrystalline) semiconductor (for example, Si, InP or GaAs).Substrate 140 also can be formed by inorganic material, for example polymkeric substance (for example plastics).

Etching stopping layer 130 forms (seeing following discussion) by the material of the etch process that forms material that can resist etching ingredient 112.The material that forms etching stopping layer 130 also should be compatible with the material of substrate 140 and formation retardation layer 110.The examples of material that can form etching stopping layer 130 comprises HfO ₂, SiO ₂, Ta ₂O ₅, TiO ₂, SiN _xOr metal (for example Cr, Ti, Ni).

The thickness of etching stopping layer 130 can change as required.Usually, etching stopping layer 130 is thick in being enough to prevent substrate 140 by obviously etchings, but should be not thick in the optical property that has a strong impact on optical delay 100.In certain embodiments, the about 500nm of etching stopping layer or littler (for example, about 250nm or littler, about 100nm or littler, about 75nm or littler, about 50nm or littler, about 40nm or littler, about 30nm or littler, about 20nm or littler).

Overlayer 120 is formed by ingredient 111 identical materials with retardation layer 110, and a surface 121 is provided usually, and other layer (for example forming antireflecting film 150 etc.) can be deposited on described surperficial 121.Surface 121 can be roughly flat.

Antireflecting film 150 and 160 can reduce and is incident on the optical delay 100 and the reflection of light of the wavelength X of outgoing.Antireflecting film 150 and 160 generally includes the different layer of one or more refractive indexes.As an example, one or two in the antireflecting film 150 and 160 can be formed by four layers that high low-refraction replaces.High refractive index layer can be by TiO ₂Or Ta ₂O ₅Form, and low-index layer can be by SiO ₂Or MgF ₂Form.Antireflecting film can be broadband antireflecting film or narrow-band antireflecting film.

In certain embodiments, the light of 100 pairs of incidents of optical delay wavelength X thereon has about 5% or littler reflectance (for example, about 3% or littler, about 2% or littler, about 1% or littler, about 0.5% or littler, about 0.2% or littler).In addition, optical delay 100 can have high transmittance to the light of wavelength X.For example, the light transmissive about 95% of 100 pairs of incidents of optical delay wavelength X thereon or more (for example, about 98% or more, about 99% or more, about 99.5% or more).

Usually, optical delay 100 can prepare as required.Fig. 2 A-2J illustrates the different conditions of preparation process example.Beginning provides substrate 140, shown in Fig. 2 A.The surface 141 of substrate 140 can polish and/or clean (for example, by with exposure of substrates in one or more solvents, acid and/or cure substrate).

With reference to Fig. 2 B, etching stopping layer 130 is deposited on the surface 141 of substrate 140.The material that forms etching stopping layer 130 can be with a kind of formation in the various technology, comprise that sputter (for example, radio-frequency sputtering), evaporation (for example electron beam evaporation plating, ion assisted deposition (IAD) electron beam evaporation plating) or chemical vapour deposition (CVD) (for example plasma enhanced CVD (PECVD)), ALD or oxidation.As an example, HfO ₂Layer can be deposited on the substrate 140 by the IAD electron beam evaporation plating.

With reference to Fig. 2 C, middle layer 210 is deposited on the surface 131 of etching stopping layer 130 then.The 210 beginning etching ingredients 112 from the middle layer, so middle layer 210 is formed by the material that is used for ingredient 112.The material that forms middle layer 210 can be by comprising a kind of deposit in sputter (for example radio-frequency sputtering), evaporation (for example electron beam evaporation plating) or the various technology of chemical vapour deposition (CVD) (for example plasma enhanced CVD).As an example, SiO ₂Layer can be deposited on the etching stopping layer 130 by sputter (for example radio-frequency sputtering), CVD (for example plasma enhanced CVD) or electron beam evaporation plating (for example IAD electron beam deposition).Select the thickness in middle layer 210 according to the desired thickness of retardation layer 110.

Adopt countermark technology processing middle layer 210, with the ingredient 112 that retardation layer 110 is provided.For example, can adopt electron beam lithography or photoetching (for example using photomask or holographic technique), form ingredient 112 by middle layer 210.In certain embodiments, ingredient 112 forms by nano impression mint-mark (nano-imprint lithographic) technology.With reference to Fig. 2 D, the nano impression mint-mark is included in and forms resist layer 220 on the surface 211 in middle layer 210.Resist can be for example polymethylmethacrylate (PMMA) or polystyrene (PS).With reference to Fig. 2 E, pattern is engraved in the resist layer 220 with mould.The resist layer 220 that is printed on pattern comprises thin composition ingredient 221 and thick ingredient 222.Be printed on the resist layer 220 etched (for example) of pattern then, remove the ingredient 224 of thin ingredient 221, shown in Fig. 2 F with the surface 211 in exposure middle layer 210 by oxygen reactive ion etching (RIE).Thick ingredient 222 is also etched, but is not removed fully.Therefore, the ingredient 223 of resist is being stayed after the etching on the surface 221.

With reference to Fig. 2 G, 210 exposed portions quilt in middle layer forms groove 212 with after etching in middle layer 210.The not etching part in middle layer 210 is corresponding to the ingredient 112 of retardation layer 110.Middle layer 210 can the etching by for example reactive ion etching, ion beam milling, sputter etching, chemically assisted ion beam etching (CAIBE) or wet etching.The expose portion in middle layer 210 is etched down into the etching stopping layer 130 that is formed by the material that can resist described engraving method.Therefore, the degree of depth of groove 212 and being of uniform thickness of ingredient 112 of etching formation.Behind etched trench 212, residual resist 223 is removed from ingredient 112.Resist can be by removing with O2 plasma ashing, O2RIE or ozone clean method cleaning article in solvent (for example, organic solvent is as acetone or alcohol).

With reference to Fig. 2 I, after removing remaining resist, deposition of materials is to goods, and filling groove 212 also forms overlayer 120.The groove that is filled is corresponding to the ingredient 111 of retardation layer 110.Material can be deposited on the goods in every way, comprises sputter, electron beam evaporation plating, CVD (as high density CVD) or atomic layer deposition (ALD).Notice that form under the situation of overlayer 120 and filling groove 212, ingredient 111 and overlayer 120 are formed by the continuous part of material in same depositing step.

At last, antireflecting film 150 and 160 is deposited to respectively on the surface 142 of the surface 121 of overlayer 120 and substrate 140.The material that forms antireflecting film can be deposited on the goods by for example sputter, electron beam evaporation plating or ALD.

As previously mentioned, in certain embodiments, one or two in the ingredient 111 of retardation layer 110, overlayer 120 and/or antireflecting film 150 and 160 is by the preparation of atomic layer deposition (ALD) method.For example, with reference to Fig. 3, ALD system 300 is used for the nano composite multiple layer film is filled into intermediate 301 groove 212 of (being made up of substrate 140, etching stopping layer 130 and ingredient 112), forms ingredient 111 and overlayer 120.If provide abundant control to film component and thickness, the deposit of nano composite multiple layer film individual layer ground one by one realizes.During the deposit individual layer, the steam of parent imports to indoor and is absorbed on individual layers adjacent with these surfaces of exposed surface, the etching stopping layer surface 131 of ingredient 112 or previous deposit.Then, be imported in the chamber, to form the individual layer of material requested with the reactant of the parent generation chemical reaction that is absorbed.The limiting character certainly and can provide of the chemical reaction that takes place on the surface to the accurate control of film thickness and the large-scale homogenieity of illuvium.In addition, no matter parent absorbs directionlessly material surface evenly is deposited on the exposed surface with respect to the orientation of retardation layer 110.Therefore, the rete of nanometer multilayer complex formation is adapted to the shape of the groove of intermediate 301.

ALD system 300 comprises the reaction chamber 310 that is connected to source 350,360,370,380 and 390 by collector 330.Source 350,360,370,380 and 390 is connected to collector 330 by supply line 351,361,371,381 and 391 respectively.Valve 352,362,372,382 and 392 is regulated the air-flow from source 350,360,370,380 and 390 respectively.Source 350 and 380 comprises first and second parents respectively, and source 360 and 390 comprises first reactant and second reactant respectively.Source 370 is included in the vector gas by reaction chamber 310 of continuous flow in the deposition process, is used for parent and reactant are transported to goods 301, byproduct of reaction is carried left substrate simultaneously.Parent and reactant mix with vector gas in collector 330 and are transported in the reaction chamber 310.Gas is discharged from reaction chamber 310 by outlet 345.Pump 340 is discharged gas by outlet 345 from reaction chamber 310.Pump 340 is connected to outlet 345 by pipeline 346.

ALD system 300 comprises temperature controller 395, the temperature of control reaction chamber 310.During the deposit, temperature controller 395 is brought up to the temperature of goods 301 on the room temperature.Usually, this temperature should be high enough to promote rapid reaction between parent and the reactant, but should not damage substrate.In certain embodiments, the temperature of goods 301 can be about 500 ℃ or lower (for example, about 400 ℃ or lower, about 300 ℃ or lower, about 200 ℃ or lower, about 150 ℃ or lower, about 125 ℃ or lower, about 100 ℃ or lower).

Usually, temperature is not answered significant change between the different piece of intermediate 301.Big temperature variation can cause the variation of reaction velocity between the parent and reactant on the different piece of substrate, and this can cause illuvium thickness and/or modal variation.In certain embodiments, between the deposition surface different piece variable temperaturesization about 40 ℃ or littler (for example, about 30 ℃ or littler, about 20 ℃ or littler, about 10 ℃ or littler, about 5 ℃ or littler).

The deposition process parameter is by electronic controller 399 controls and synchronous.Electronic controller 399 and temperature controller 395, pump 340, and valve 352,362,372,382 and 392 communications.Electronic controller 399 also comprises user interface, and the operator can be provided with the deposition process parameter thus, monitors deposition process, and is perhaps mutual with system 300.

With reference to Fig. 4, in system 300 by mixing with vector gas and when it being imported in the reaction chamber 310 (step 420), the ALD process begins (step 410) from first parent in source 350 from source 370.The individual layer of first parent is absorbed on the exposed surface of goods 301, and residual parent cleans out reaction chamber 310 (step 430) by the continuous carrier gas stream by reaction chamber.Then, system 360 imports first reactant in the reaction chambers 310 (step 440) by collector 330 from the source.The individual layer of first reactant and first parent reacts, and forms the individual layer of first material.To first parent, carrier gas stream cleans, to remove residual reactants (step 450) from reaction chamber.Repeating step 420 to 460 reaches desired thickness (step 460) up to first material layer.

At film is among the embodiment of single material layer, in case first material layer reaches desired thickness, this process promptly stops (step 470).But for the film that is formed by the nanometer multilayer complex, system imports second parent in the chamber 310 (step 380) by collector 330.The individual layer of second parent is absorbed on the exposed surface of illuvium of first material, and the residual parent (step 490) of vector gas cleaning reaction chamber.System imports second reactant in the reaction chamber 310 from source 380 by collector 330 then.The individual layer of second reactant and second parent reacts, and forms the individual layer (step 500) of second material.Vector gas stream by reaction chamber cleans residual reactants (step 510).Repeating step 580 to 510 reaches desired thickness (step 520) up to second material layer.

Other first and second material layer of deposit by repeating step 520 to 530.In case the layer of requirement forms (for example groove is filled and/or overlayer has desired thickness), this process stops (step 540), and the goods of plated film are taken out from reaction chamber 310.

Although each cycle period in said process, parent was imported in the chamber before reactant, yet, in other embodiments, can before parent, import reactant.The order that parent and reactant import can be selected according to the interaction of they and exposed surface.For example, if when the bonded energy between parent and the surface is higher than bonded energy between reactant and the surface, then parent can import before reaction.Perhaps, if the bonded energy of reactant is higher, can before parent, import reactant.

The thickness of each individual layer depends on Several Factors usually.For example, the thickness of each individual layer can be depending on the type of material that is deposited.The material of forming with micromolecule compares, and bigger molecular material can form thicker individual layer.

Temperature of articles also can influence thickness in monolayer.For example, for some parent, deposit cycle period, higher temperature can reduce parent and be absorbed into lip-deep degree, compares when low with substrate temperature thus, can form thinner individual layer.

The type of parent and the type of reactant, and the dosage of parent and reactant also can influence the thickness of individual layer.At some embodiment, a kind of a plurality of individual layers of material can be with specific parent deposit, but under the situation of differential responses thing, every kind of combination can form different thickness in monolayer.Similarly, a plurality of individual layers of a kind of material that is formed by different parents can form different thickness in monolayer by corresponding each parent.

The example that can influence the other factors of thickness in monolayer comprises that cleaning frequency, parent are in the pressure of the coating surface residence time, reactor, the physical form and the secondary product influence possible to deposition materials of reactor.The example that secondary product influences film thickness is that secondary product can the etching deposition materials.For example, HCl uses TiCl ₄Parent and water are as reactant deposit TiO ₂The time secondary product.But the TiO of HCl etching institute deposit before discharging ₂The etching meeting reduces the thickness of institute's deposit individual layer, if and some part of substrate than the time that other parts are exposed to HCl longer (for example near the substrate portion of exhaust apparatus can be relatively to be exposed to time of secondary product away from the substrate portion of exhaust apparatus longer), can cause that thickness in monolayer changes on the whole base plate.

Usually, thickness in monolayer arrives between about 5nm at about 0.1nm.For example, the thickness of one or more deposit individual layers can be about 0.2nm or bigger (for example, about 0.3nm or bigger, approximately 0.5nm or bigger).In certain embodiments, the thickness of one or more deposit individual layers can be about 3nm or littler (for example, about 2nm, approximately 1nm or littler, approximately 0.8nm or littler, approximately 0.5nm or littler).

Individual layer by deposition preset quantity on substrate provides a kind of material layer to determine on average deposit thickness in monolayer.Then, measure the thickness (for example, by ellipsometry, electron microscope method or other method) of illuvium.Then, the layer thickness that records can be determined average deposit thickness in monolayer divided by the deposit period.Average deposit thickness in monolayer can be corresponding to theoretical monolayer thickness.Theoretical monolayer thickness refers to the characteristic dimension of the molecule of forming individual layer, and this can be calculated by the volume density of material and the molecular weight of molecule.For example, SiO ₂Thickness in monolayer be estimated as～0.37nm.This thickness estimation is that density is the amorphous Si O of every cubic centimetre of 2.0 gram ₂The cubic root of formula unit (formula unit).

In certain embodiments, average deposit thickness in monolayer can be corresponding to the mark of theoretical monolayer thickness (for example, be approximately 0.2 theoretical monolayer thickness, be approximately 0.3 theoretical monolayer thickness, be approximately 0.4 theoretical monolayer thickness, be approximately 0.5 theoretical monolayer thickness, be approximately 0.6 theoretical monolayer thickness, be approximately 0.7 theoretical monolayer thickness, be approximately 0.8 theoretical monolayer thickness, be approximately 0.9 theoretical monolayer thickness).Perhaps, average deposit thickness in monolayer can corresponding to arriving a times of theoretical monolayer thickness more about 30 times (for example, be approximately more than 2 times or more theoretical monolayer thickness, be approximately more than 3 times or more theoretical monolayer thickness, be approximately more than 5 times or more theoretical monolayer thickness, be approximately more than 8 times or more theoretical monolayer thickness, be approximately more than 10 times or more theoretical monolayer thickness, be approximately more than 20 times or more theoretical monolayer thickness).

In deposition process, the pressure in the reaction chamber 310 can remain on the roughly pressure of constant, perhaps can change.Control can be controlled this pressure usually by the flow velocity of the vector gas of reaction chamber.Usually, this pressure should be high enough to and allow parent to make the surface saturated by the material of chemical absorbing, and the surface mass that allows reactant and parent to stay fully reacts and stays reflecting point for next round-robin parent.If the hypotony of reaction chamber (this crosses at parent and/or reactant dosage and can take place when low), if and/or pump speed too high, the surface may be unsaturated by parent, then reaction may not be from restriction.This can cause in the illuvium in uneven thickness.In addition, reaction chamber pressure should be not high to hindering the reaction product that removes parent and reactant.Instantly the parent of a dosage imports when indoor, and residual secondary product may disturb the saturated of surface.In certain embodiments, pressure in reaction chamber remain on about 0.01Torr and approximately between the 100Torr (for example, at about 0.1Torr with approximately between the 20Torr, between about 0.5Torr and about 10Torr, for example about 1Torr).

Usually, the parent of each cycle period importing and/or reaction volume can be selected according to size, exposed substrate surface area and/or the chamber pressure of reaction chamber.Can rule of thumb determine parent and/or reaction volume that each cycle period imports.

Parent and/or reaction volume that each cycle period imports can be by the switch timing controlled of valve 352,362,382 and 392.The parent that imports or the amount time quantum that each circulation is opened corresponding to each valve of reactant.Valve should be opened the sufficiently long time, provides the suitable individual layer of substrate surface to cover with the parent that imports capacity.Similarly, the amount of the reactant of each cycle period importing should be enough to and the nearly all parent reaction that is deposited on the exposed surface.Importing can increase cycling time and/or waste parent and/or reactant more than the parent and/or the reactant of necessity.In certain embodiments, parent dosage (precursor dose) (is for example opened between the corresponding valve about 0.1 second to about 5 seconds corresponding to each circulation, about 0.2 second or more, about 0.3 second or more, about 0.4 second or more, about 0.5 second or more, about 0.6 second or more, about 0.8 second or more, about 1 second or more).Similarly, reactant dosage can be equivalent to each circulation and (for example open between the corresponding valve about 0.1 second to about 5 seconds, about 0.2 second or more, about 0.3 second or more, about 0.4 second or more, about 0.5 second or more, about 0.6 second or more, about 0.8 second or more, about 1 second or more).

Time between parent dosage and the reactant dosage is corresponding to cleaning.Each duration of cleaning is answered long enough so that remove residual parent or reactant from reaction chamber, if but longer then can bootlessly increase cycling time than this.The different duration of cleaning can be identical or different in each circulation.In certain embodiments, cleaned the duration and be about 0.1 second or longer (for example, about 0.2 second or longer, about 0.3 second or longer, about 0.4 second or longer, about 0.5 second or longer, about 0.6 second or longer, about 0.8 second or longer, about 1 second or longer, about 1.5 seconds or longer, about 2 seconds or longer).Usually, cleaned the duration and be about 10 seconds or shorter (for example, about 8 seconds or shorter, about 5 seconds or shorter, about 4 seconds or shorter, about 3 seconds or shorter).

The time between the continuous parent dosage of importing is corresponding to cycling time.For the circulation of the individual layer of deposit different materials, cycling time can be identical or different.In addition, for the deposit same material, but adopt the individual layer of different parents and/or differential responses thing, cycling time can be identical or different.In certain embodiments, can be about 20 seconds cycling time or shorter (for example, about 15 seconds or shorter, about 12 seconds or shorter, about 10 seconds or shorter, about 8 seconds or shorter, about 7 seconds or shorter, about 6 seconds or shorter, about 5 seconds or shorter, about 4 seconds or shorter, about 3 seconds or shorter).Reduce cycling time and can reduce the deposition process time.

Parent is chosen as the process compatible with ALD usually, and provides required deposition materials with the reaction of reactant the time.In addition, parent and material should be compatible with thereon material of their institute's deposits (for example, with baseplate material or form the material of last illuvium).The example of fertile material comprises chloride (for example metal chloride), for example TiCl ₄, SiCl ₄, SiH ₂Cl ₂, TaCl ₃, HfCl ₄The l of company ₃And AlCl ₃In certain embodiments, organic compound can be used as parent (for example, Ti-ethaOxide, Ta-ethaOxide, Nb-ethaOxide).Another example of organic compound is (CH ₃) ₃Al.

Reactant also is chosen as usually with ALD process compatible, and selects according to the chemistry of parent and material.For example, if material is an oxide, reactant can be oxygenant.The example of the oxygenant that is suitable for comprises water, hydrogen peroxide, oxygen, ozone, (CH ₃) ₃Al and various alcohol (for example, ethanol CH ₃OH).For example, water is a kind of suitable reactant, is used for oxidation TiCl ₄Thereby such parent obtains TiO ₂, AlCL ₃Thereby, obtain Al ₂O ₃And Ta-ethaoxide, thereby obtain Ta ₂O ₅, Nb-ethaoxide, thereby obtain Nb ₂O ₅, HfCl ₄Thereby, obtain HfO ₂, ZrCl ₄Thereby, obtain ZrO ₂And InCl ₃Thereby, obtain In ₂O ₃In each case, HCl produces as secondary product.In certain embodiments, (CH ₃) ₃Al can be used for the monox alkanol so that SiO to be provided ₂

Although described certain embodiments, the present invention is not limited to this usually.For example, when optical delay 100 (see figure 1)s illustrated the concrete structure of different layers, other embodiment can comprise extra or littler layer.For example, in certain embodiments, optical delay does not need to comprise one or two in antireflecting film 150 and 160.In certain embodiments, optical delay can comprise other reflectance coating (for example between substrate 140 and etching stopping layer 130).Embodiment also can comprise protective seam on one or two of antireflecting film 150 and 160, for example hardcoat (hardcoat) layer (for example, hardcoat polymkeric substance).In certain embodiments, optical delay does not need to comprise overlayer.The overlayer that forms when for example, filling groove between the ingredient 112 can be removed when ingredient 111 forms.Overlayer can remove by for example chemically mechanical polishing or etching.

With reference to Fig. 5, in certain embodiments, by partly directly etched trench is in substrate layer, and filling groove forms optical delay 600 so that continuous delay layer 610 to be provided subsequently.Optical delay 600 also comprises overlayer 620, and corresponding to the basal layer 630 of the not etching part of original substrate.Antireflecting film 640 is deposited on the surface 621 of overlayer 620, and second antireflecting film 650 is deposited on the surface 631 of basal layer 630.

In certain embodiments, optical delay can be by forming more than a retardation layer.For example, with reference to Fig. 6, optical delay 800 comprises four retardation layers 810,820,830 and 840.Optical delay 800 also comprises substrate layer 801, etching stopping layer 805 and overlayer 811,821,831 and 841.

Retardation layer 810,820,830 can have identical delay to the light beam of wavelength X with 840, or has different delays.

Optical delay 800 can prepare with method disclosed herein.For example, can be by going up at etching stopping layer 805 (for example retardation layer 810) or (for example at last deposited capping layer, retardation layer 820,830 and 840) goes up deposit and etching middle layer, and deposition materials forms each retardation layer and corresponding overlayer thereof to fill an etched groove and to form overlayer subsequently.

In certain embodiments, other etching stopping layer can be deposited on the overlayer before forming follow-up retardation layer.Certainly, also can comprise other layer, for example anti-reflecting layer.

Usually, retardation layer 810,820,830 and 840 thickness along the z direction, the width of its ingredient (along the x direction), and the material that is used to form them can change as required.In certain embodiments, retardation layer 810,820,830 is identical with 840, and in other embodiments, one or several retardation layer can be different (for example, form by one or more materials different, have different-thickness, and/or have different birefractions) with other retardation layer.

In addition, although optical delay 800 has four retardation layers, usually, embodiment can comprise greater or less than four retardation layers.Optical delay can comprise two retardation layers, three retardation layers, and perhaps five or more retardation layers are (for example, about 10 or more retardation layers, about 20 or more retardation layers, about 30 or more retardation layers, about 100 or more retardation layers, about 1000 or more retardation layers).

Can be big relatively for total phase retardation of propagating by having more than the light of the wavelength X of the optical delay of a retardation layer.For example, the phase retardation that optical delay can have about 2 π to λ (for example, about 3 π or more, about 4 π or more, about 5 π or more, about 8 π or more, about 10 π or more, about 12 π or more, about 15 π or more, about 20 π or more, about 30 π or more).

Comprise gross thickness (along the z direction) more than the optical delay of a retardation layer can be about 200 μ m or more (for example, about 500 μ m or more, about 800 μ m or more, about 1,000 μ m or more, about 1,500 μ m or more, about 2,000 μ m or more, about 5,000 μ m or more).

In certain embodiments, optical delay can be used as the discrete crystal of optics, and non-orthogonal incident light (that is the light of not propagating along the z direction) is divided into the ordinary and extraordinary ray that leaves delayer along different paths.Wedge shape can heavily be cut and be polished into to the discrete crystal of this optics.Discrete crystal can be used in numerous application scenarios, ripple insulation (telecom isolator), circulator or interleaver (interleaver) for example, and/or in the such consumer applications of for example optical low-pass filter.

Although described the embodiment of the optical delay that comprises structural birefringence layer (form birefringentlayer), also can adopt other embodiment with rectangular grid profile.For example, in certain embodiments, the grid profile of structural birefringence layer is flexible, for example sinusoidal.In other embodiment, grid can be triangle or serrate.

In addition, although the grid cycle in the structural birefringence layer of optical delay is described to constant, in certain embodiments, this grid cycle can change.In certain embodiments, but the ingredient no periodic ground of structural birefringence layer arrange.

Described optical delay can be attached in the optical device, comprises passive optical device (for example polarizer) and active optics device (for example LCD).Optical delay can be used as monolithic device and is integrated into device, perhaps can arrange discretely with other elements of device.

With reference to Fig. 7, as example, the passive optical device that has optical delay is a polarizer 660.Polarizer 660 comprises polarizing coating 670 and optical delay 680.Polarizing coating 670 (for example can be polaroid, the iodine colored polyvinyl) or nanostructure polarizer, for example Application No. the 10/644th, disclosed in 643, title is " MULTILAYER STRUCTRURES FOR POLARIZATIONAND BEAM CONTROL ", and PCT number of patent application No.PCT/US 03/26024, title is disclosed in " METHOD AND SYSTEM FOR PROVIDING BEAM FORPOLARIZATION ", and the full content of the two is incorporated herein by reference.

Polarizing coating 670 will be propagated the light polarization that is incident on the polarizer 660 along axle 661.Optical delay 680 postpones this linearly polarized photon then, makes polarized light leave polarizer 660 with required ellipticity.The ellipticity of emergent light can be as required by selecting the parameter relevant with the retardation layer of optical delay 680 to change so that required retardation to be provided.For example, emergent light can be circularly polarized light or elliptically polarized light.

With reference to Fig. 8, the example that has the active optics device of optical delay is a LCD 700, (for example comprise substrate 710, silicon substrate), reflecting electrode 720, liquid crystal layer 730 are (for example, to row or ferroelectric liquid crystal layer), transparency electrode 740 (for example, forming), optical delay 750 and polarizing coating 760 by indium tin oxide.Optical delay 750 postpones the polarized light of transmission by polarizing coating 760.This light is from electrode 720 reflection, propagates by liquid crystal layer 730 twice.Before being incident on the polarizing coating 760 for the second time, reflected light is postponed by optical delay 750 once more.According to the voltage that is applied between electrode 720 and 740, reflected light is polarized film 760 and absorbs or transmission, respectively corresponding to dark or bright pixel.Selectively, LCD 700 comprises the colored filter that absorbs specific wavelength in the visible spectrum, thereby coloured image is provided.Although LCD 700 is reflective display, optical delay disclosed herein can be used in the display of other type, for example transmissive display or Transflective display.

Following example is schematically not mean that restriction.

Example

Optical delay is prepared as follows.(Santa Paula, the BK7 wafer that CA) 0.5mm of Huo Deing is thick (four inches of diameters) is by using H from Abrisa company ₂O:H ₂O ₂: NH ₄The undissolvable organic dirt of OH solution removal is used H ₂O:H ₂O ₂: HCl solution removal ion and heavy metal atom dirt.Then, with isopropyl alcohol and rinsed with deionized water wafer, and dry.

The long grid of wavelet is following to be etched in the BK7 wafer.(～180nm) PMMA (buying molecular weight 15K from St. Louis, Missouri State Sigma-Aldrich), baking is about one hour on about 115 ° hot plate by the spin coating skim for the BK7 wafer.After the baking, with the grid die marks resist of cycle 200nm, the about 110nm of the degree of depth, the about 100nm of grid line distance.Mould is included in the SiO through composition on the thick silicon substrate of 0.5mm ₂Layer (approximately 200nm is thick).Mould J.Wang, Z.Yu, and S.Y.Chou, at J.Vac.Sci.Technol., the preparation of B 17,2957 (1999) disclosed methods.After the impression, the UV of distortion solidifies resist and is exposed to UV light and full solidification by the BK7 substrate-side.Mould separates with resist then, forms the mask of the reverse pattern with mould.Mask O ₂The RIE etching is exposed up to the recess of BK7 wafer at mask.This etching plasma-therm 790 (Unaxis of Sankt Peterburg, Florida, Inc. provides).Pressure during the etching is 4mtorr.Power setting is at 70W, and the oxygen gas flow rate during the etching is 10sccm.The gross thickness that etches into the resist that exposes BK7 is about 120nm.

Behind etching mask, approximately the Cr of 50nm passes through in high vacuum (that is, less than about 5 * 10 ^-6Torr) be deposited on the BK7 wafer of residue resist/expose with the angle that tilts with wafer normal by electron beam evaporation plating under the environment.The pitch angle is about 65 degree.Cr is deposited on the top and sidewall of residue mask line (mask line), and the hard mold of etching BK7 is provided.After the Cr deposit, reuse O ₂The resist of any exposure that is not covered by Cr of RIE etching.Use CHF then ₃The part that RIE etching BK7 wafer surface is exposed is to form the long grid of wavelet in the wafer.BK7 plasma-term 720 etchings.Constant pressure is about 5mtorr, and power is about 100W, used CHF ₃And O ₂Flow velocity be respectively 10sccm and 1sccm.In the BK7 wafer, etch the groove of the about 630nm of the wide degree of depth of 100nm.Behind the etching BK7, wafer is immersed about 30 minutes removal Cr the CR-7Cr etchant (obtaining from the Cyantek in California Freemont city).Then by O ₂RIE removes residual resist.

Groove is used by TiO ₂And SiO ₂The nanometer multilayer compound substance of forming is filled.Carry out ALD deposit nanometer multilayer compound substance with the P-400A ALD device that obtains from PlanarSystems company (Oregon is than not pausing).Before deposit nanometer multilayer complex, etched wafer the ALD chamber interior be heated to 300 ℃ about three hours.The ALD chamber is washed in order to about 2SLM flowing nitrogen, and keeping constant pressure is about 0.75Torr.TiO ₂Parent is to be heated to about 140 ° Ti-ethaoxide.SiO ₂Parent is to be heated to about 110 ° silanol.For two kinds of parents, used reactant is to remain on about 13 ° water.Ti-ethaoxide and silanol are 99.999% grade of purity, obtain from Sigma-Aldrich (St. Louis, the Missouri State).The nanometer multilayer complex is by repeating deposit 10 individual layer TiO ₂Deposit one individual layer SiO then ₂Circulation and form.Be deposit TiO ₂Individual layer, the water that carried out 2 seconds imports chamber, and the nitrogen that then carried out 2 seconds cleans.Ti-ethaoxide imports chamber then, then carries out two seconds nitrogen purge in addition.By water being imported the ALD chamber 1 second, the nitrogen that then carried out 2 seconds cleans and deposit SiO ₂Individual layer.Imported silanol then 1 second.Before next reactant enters, use nitrogen wash chamber 3 seconds then.Determined as the nanometer multilayer complex for preparing on flat glass substrate is similarly measured, the refractive index of nanometer multilayer complex is estimated as approximate 1.88 at 632nm.

The delay M-2000V of optical delay

It is 23.85nm that beam split ellipsograph (can obtain from Nebraska State Lincoln city J.A.Woollam company limited is commercial) is measured as when wavelength 551nm.

With the grid that scanning electron microscopy research is not filled and filled, available LEO heat emission scanning electron microscope is carried out.For carrying out this research, sample is rived and is applied with skim Au.Observe the section of section then.Fig. 9 A and 9B illustrate before the trench fill respectively and SEM microphoto afterwards.

Other embodiment is in claims.

Claims (43)

1. method comprises:

A kind of goods are provided, comprise first material layer, this first material layer comprises at least one groove, and this first material layer is for the only structural birefringence of propagating the wavelength X by this first material layer along axle, wherein λ at 150nm between the 2000nm; And

The volume of filling groove at least 50% by the individual layer that in this groove, forms a plurality of second materials successively.

2. according to the process of claim 1 wherein, described filling further is included in the individual layer that forms one or more the 3rd materials in the groove, and wherein, second is different with the 3rd material.

3. according to the method for claim 2, wherein, the individual layer of the second and the 3rd material forms the nanometer multilayer compound substance.

4. according to the process of claim 1 wherein, by the individual layer that in groove, forms a plurality of second materials successively at least 80% of the volume of filling groove.

5. according to the process of claim 1 wherein, by the individual layer that in groove, forms a plurality of second materials successively at least 90% of the volume of filling groove.

6. according to the process of claim 1 wherein, by the individual layer that in groove, forms a plurality of second materials successively at least 99% of the volume of filling groove.

7. according to the process of claim 1 wherein, second material is different with first material.

8. according to the process of claim 1 wherein, the individual layer of first material layer and a plurality of second materials forms successive layers.

9. according to the process of claim 1 wherein, goods are included in the extra groove that forms in the surface of first material layer.

10. according to the method for claim 9, wherein, described method further comprise by the individual layer that in extra groove, forms a plurality of second materials successively fill each extra groove volume at least 50%.

11. according to the method for claim 9, wherein, described method further comprise by the individual layer that in extra groove, forms a plurality of second materials successively fill each extra groove volume at least 80%.

12. according to the method for claim 9, wherein, described method further comprise by the individual layer that in extra groove, forms a plurality of second materials successively fill each extra groove volume at least 90%.

13. according to the method for claim 9, wherein, described method further comprise by the individual layer that in extra groove, forms a plurality of second materials successively fill each extra groove volume at least 99%.

14. according to the method for claim 9, wherein, described extra groove is by the capable separation of first material.

15. according to the method for claim 7, wherein, first material layer forms the concave-convex surface grid.

16. according to the method for claim 15, wherein, the concave-convex surface grid has 500nm or littler pitch.

17. according to the method for claim 7, wherein, groove is formed by the successive layers of etching first material.

18. according to the method for claim 17, wherein, etching comprises reactive ion etching.

19. according to the process of claim 1 wherein, groove forms with countermark technology.

20. according to the method for claim 19, wherein, groove forms with the nano impression lithography.

21. according to the method for claim 20, wherein, the nano impression lithography is included in and forms pattern on the thermoplastic.

22. according to the method for claim 20, wherein, the nano impression lithography is included on the UV curing materials and forms pattern.

23. according to the method for claim 19, wherein, groove forms with holographic lithography.

24., further comprise by forming second material layer above the groove that is being filled forming the individual layer of each second material successively above the groove according to the process of claim 1 wherein.

25. according to the method for claim 24, wherein, second material layer has the surface of 50nm or littler arithmetic average roughness.

26. according to the process of claim 1 wherein, second material is a dielectric material.

27. according to the process of claim 1 wherein, the individual layer that forms a plurality of second materials comprises the individual layer of deposit parent and the individual layer of parent is exposed to reactant, so that the individual layer of second material to be provided.

28. according to the method for claim 27, wherein, reactant and parent chemical reaction are to form second material.

29. according to the method for claim 28, wherein, reactant oxidation parent forms second material.

30. according to the method for claim 27, wherein, the individual layer of deposit parent comprise will comprise first gas of parent import and hold in the chamber of goods.

31. according to the method for claim 30, wherein, during the individual layer of deposit parent, the pressure of first gas is 0.01 to 100Torr in the chamber.

32., wherein, the individual layer of parent is exposed to reactant comprises the second gas introduction chamber that comprises reactant indoor according to the method for claim 30.

33. according to the method for claim 32, wherein, when the individual layer of parent was exposed to reactant, the pressure of second gas was 0.01 to 100Torr in the chamber.

34. according to the method for claim 32, wherein, after importing first gas, import before second gas, the 3rd gas introduction chamber is indoor.

35. according to the method for claim 34, wherein, the 3rd gas is inertia for parent.

36. according to the method for claim 34, wherein, the 3rd gas comprises at least a gas of selecting from the group of being made up of helium, argon gas, nitrogen, neon, krypton gas and xenon.

37. according to the method for claim 27, wherein, parent is from by 3-tert-butoxy silanol, (CH ₃) ₃Al, TiCl ₄, SiCl ₄, SiH ₂Cl ₂, TaCl ₃, AlCl ₃, select in the group that Hf-ethaoxide and Ta-ethaoxide form.

38. according to the process of claim 1 wherein, the width of groove is 1000nm or littler.

39. according to the process of claim 1 wherein, the degree of depth of groove is 10nm or more.

40. method according to Claim 8, wherein, successive layers is only birefringent for the wavelength X of passing through successive layers along the axle propagation, and wherein, λ is between 150nm and 2000nm.

41., further be included in and on first material layer, form second birefringent layers behind the filling groove according to the process of claim 1 wherein.

42. according to the method for claim 41, wherein, second birefringent layers comprises a plurality of grooves, and forms second birefringent layers and comprise by the individual layer that forms a plurality of the 3rd materials in the groove of second birefringent layers successively and fill a plurality of grooves.

43., wherein, further be included in the extra birefringent layers of formation on second birefringent layers according to the method for claim 41.

Images