Oxide buffer layer that promotes TiO2 crystallinity and increases the TiO2 refractive index for optical applications

Abstract

The disclosed and claimed method provides a method for generating rutile TiO with a high refractive index at moderate process temperatures. 2 ​

Description

Technical Field

[0001] (Technical Field)

[0002] The disclosed and claimed subject matter relates to a method for producing rutile TiO₂ with a high refractive index at moderate process temperatures. 2 for producing rutile TiO₂ with a high refractive index at moderate process temperatures.

Background Art

[0003] (Related Art)

[0004] TiO₂ 2 is widely used as a high refractive index material in a plurality of optical coating applications including antireflection coatings, LED components, display components, Bragg reflectors, lenses, and the like. TiO₂ 2 exhibits one of the highest refractive indices among binary transition metal oxides while maintaining negligible light absorption in the visible range. Also, it is an extremely stable oxide and is attractive from the viewpoint of integration. In particular, a higher TiO₂ refractive index improves BDR (distributed Bragg reflector) or ODR (omnidirectional reflector) performance, which provides important value to optical coatings.

[0005] Unfortunately, deposition by known methods such as sputtering or vapor deposition processes results in a TiO₂ layer having a refractive index of only about 2.4 - 2.6 at 460 nm. For example, TiO₂ deposited at room temperature exhibits an amorphous structure with a relatively low refractive index (2.4 at 460 nm). The anatase phase is formed at low process temperatures but also has a relatively low refractive index comparable to the amorphous phase. The rutile phase is the most attractive for optical coating applications as it exhibits a very high refractive index (2.7 - 3 at 460 nm), but requires high temperature treatment (600 °C) to be formed. This requirement makes the application of rutile TiO₂ very difficult and impractical from the viewpoint of integration for applications using glass or plastic substrates. 2 For example, TiO₂ deposited at room temperature 2 exhibits an amorphous structure with a relatively low refractive index (2.4 at 460 nm). The anatase phase is formed at low process temperatures but also has a relatively low refractive index comparable to the amorphous phase. The rutile phase is the most attractive for optical coating applications as it exhibits a very high refractive index (2.7 - 3 at 460 nm), but requires high temperature treatment (600 °C) to be formed. This requirement makes the application of rutile TiO₂ very difficult and impractical from the viewpoint of integration for applications using glass or plastic substrates. 2 This requirement makes the application of rutile TiO₂ very difficult and impractical from the viewpoint of integration for applications using glass or plastic substrates.

[0006] Preferably, the high refractive index TiO 2 is deposited by a conventional deposition process. Such processes include physical vapor deposition (PVD), chemical vapor deposition (CVD), plasma enhanced CVD (PECVD), fluidized CVD (FCVD), atomic layer deposition (ALD), and spin-on processes.

[0007] Transition metal-containing films are used in semiconductor and electronics applications. CVD and ALD have been applied as the main deposition techniques for producing thin films for semiconductor devices. These methods enable the achievement of conformal films (metals, metal oxides, metal nitrides, metal silicides, etc.) through the chemical reaction of metal-containing compounds (precursors). The chemical reaction occurs on a surface that may include metals, metal oxides, metal nitrides, metal silicides, and other surfaces. In CVD and ALD, precursor molecules play an important role in achieving high-quality films with high conformality and low impurities. The temperature of the substrate in the CVD and ALD processes is an important consideration when selecting precursor molecules. Higher substrate temperatures in the range of 150 to 500 degrees Celsius (°C) promote higher film growth rates. Preferred precursor molecules must be stable in this temperature range. Preferred precursors can be supplied to the reaction vessel in the liquid phase. Liquid phase delivery of the precursor generally provides a more uniform delivery of the precursor to the reaction vessel than solid phase precursors.

[0008] Unfortunately, CVD and ALD do not enable the deposition of high refractive index materials at lower temperatures. For example, if CVD or ALD is performed at 600 °C, it may be possible to see the rutile phase of TiO 2 . Therefore, it is desirable to develop a method that can achieve the rutile phase at a lower temperature, thereby enabling deposition on sensitive substrates.

[0009] The disclosed and claimed PVD process addresses the above problems associated with CVD and ALD. PVD is a physical method for the deposition of films. A PVD system consists of a vacuum chamber that can maintain a vacuum during deposition and allow for the controlled insertion of different gases at a typical pressure of 1 mTorr to 10 mTorr. One or several solid targets are inserted into the chamber and serve as the source of the deposition material. In the case of magnetron sputtering deposition, an array of magnets is placed behind the surface of the target to help maintain a plasma in their vicinity. The disclosed and claimed subject matter relates to a method of forming a high refractive index layer (e.g., high refractive index rutile TiO 2 ) using a PVD process at low temperature.

SUMMARY OF THE INVENTION

[0010] The disclosed and claimed method addresses these concerns and largely eliminates them by providing a method for generating high refractive index rutile TiO 2 at moderate process temperatures.

[0011] In another embodiment, the disclosed and claimed subject matter includes the generation of high refractive index rutile TiO 2 in a PVD deposition process.

BRIEF DESCRIPTION OF THE DRAWINGS

[0012] The accompanying drawings are included to provide a further understanding of the disclosed subject matter, are incorporated herein, form a part of this specification, show embodiments of the disclosed subject matter, and together with the detailed description serve to explain the principles of the disclosed subject matter. The drawings are as follows.

[0013]

Figure 1

DETAILED DESCRIPTION OF THE INVENTION

[0014] All references, including publications, patent applications, and patents cited in this specification, are hereby incorporated by reference in their entirety to the same extent as if each reference were individually and specifically indicated to be incorporated by reference and were set forth in its entirety herein.

[0015] In the context of describing the disclosed and claimed subject matter (particularly in the context of the following claims), the use of the terms "a," "an," and "the," and similar references, shall be construed to cover both the singular and the plural forms, unless otherwise indicated herein or clearly contradicted by the context. The terms "comprising," "having," "including," and "containing" shall be construed as open-ended terms (i.e., meaning "including, but not limited to") unless otherwise noted. The recitation of ranges of values herein is merely intended to serve as a shorthand method of referring individually to each separate value falling within the range, and each separate value is hereby incorporated herein as if it were individually recited herein. All methods described herein can be performed in any suitable order unless otherwise indicated herein or clearly contradicted by the context. The use of any and all examples, or exemplary language (e.g., "such as") provided herein is merely intended to better illuminate the disclosed and claimed subject matter and does not impose a limitation on the scope of the disclosed and claimed subject matter unless otherwise claimed. No language in this specification should be construed as indicating any non-claimed element as essential to the practice of the disclosed and claimed subject matter. The use of the terms "comprising" or "including" in this specification and the claims encompasses the more restrictive language "consisting essentially of" and "consisting of."

[0016] Embodiments of the disclosed and claimed subject matter are described herein, including what the inventors believe to be the best mode of practicing the disclosed and claimed subject matter. Variations of these embodiments may become apparent to those of ordinary skill in the art upon reading the foregoing description. The inventors expect those of ordinary skill in the art to employ such variations as appropriate, and the inventors intend for the disclosed and claimed subject matter to be practiced otherwise than as specifically described herein. Accordingly, the disclosed and claimed subject matter includes all modifications and equivalents of the subject matter recited in the claims appended hereto as permitted by applicable law. Further, any combination of the above-described elements in all possible variations thereof is included in the disclosed and claimed subject matter unless otherwise indicated herein or otherwise clearly contradicted by context.

[0017] The headings used herein are not intended to be limiting and, rather, are included for organizational purposes only.

[0018] PVD process

[0019] As described above, the disclosed and claimed subject matter relates to a method for producing rutile TiO₂ with a high refractive index at a moderate process temperature. As-deposited TiO₂ is generally amorphous even at substrate temperatures up to 250°C. As a result, the refractive index of the thin film TiO₂ is always low. 2 for producing rutile TiO₂ with a high refractive index at a moderate process temperature. As-deposited TiO₂ is generally amorphous even at substrate temperatures up to 250°C. As a result, the refractive index of the thin film TiO₂ is always low. 2 is generally amorphous even at substrate temperatures up to 250°C. As a result, the refractive index of the thin film TiO₂ is always low. 2 is always low.

[0020] In the disclosed and claimed method, a suitable buffer layer is applied to facilitate the crystalline formation of TiO₂ in subsequent deposition steps. When utilized, the method produces TiO₂ having an undesirable rutile crystal structure when a template transition metal oxide layer buffer layer having the same (or substantially the same) crystal structure and similar lattice constant / spacing as TiO₂ is used. In one embodiment, the template layer is SnO₂, GeO₂, 2 is applied to facilitate the crystalline formation of TiO₂ in subsequent deposition steps. When utilized, the method produces TiO₂ having an undesirable rutile crystal structure when a template transition metal oxide layer buffer layer having the same (or substantially the same) crystal structure and similar lattice constant / spacing as TiO₂ is used. In one embodiment, the template layer is SnO₂, GeO₂, 2 is used, TiO₂ having an undesirable rutile crystal structure is produced when a template transition metal oxide layer buffer layer having the same (or substantially the same) crystal structure and similar lattice constant / spacing as TiO₂ is used. In one embodiment, the template layer is SnO₂, GeO₂, 2 to produce. In one embodiment, the template layer is SnO₂, GeO₂, 2 GeO₂, 2, TaO 2 and TeO 2 and includes one or more of them. In one embodiment, the template layer is SnO 2 including. In one embodiment, the template layer is GeO 2 including. In one embodiment, the template layer is TaO 2 including. In one embodiment, the template layer is TeO 2 including. For example, SnO 2 has a lattice constant very close to rutile TiO 2 and crystallizes at low temperatures, making it a good candidate. Table 1 [Table 1]

[0021] The disclosed and claimed PVD process utilizes a mixture of oxygen and one or more inert gases. Exemplary purge gases include argon (Ar), nitrogen (N 2 ), helium (He), neon (Ne), and mixtures thereof. In one embodiment, the inert gas includes argon (Ar). In one embodiment, the inert gas includes nitrogen (N 2 ). In one embodiment, the inert gas includes helium (He). In one embodiment, the inert gas includes neon (Ne).

[0022] The disclosed and claimed subject matter includes a film deposited by the disclosed and claimed PVD process. The film has a thickness of about 10 Å to about 50 Å.

[0023] Process parameters

[0024] In one embodiment, the disclosed and claimed PVD process is (1) Using a first target, depositing a template layer containing one or more of the metal oxides selected from the group of SnO 2 , GeO 2 , TaO 2 , TeO 2 on the substrate surface, the following steps (a) Step of heating the substrate to a temperature of about 100 °C to about 400 °C, and (b) Step of introducing a mixture of oxygen (O) and one or more inert gases, and (c) Step of performing reactive sputtering by applying a voltage to a first target to generate plasma, and Step of depositing a template layer having a thickness of about 10 Å to about 125 Å, (2) Step of depositing a high refractive index layer of rutile TiO on the template layer using a second target, 2 which includes the following steps: (a) Step of heating the substrate to a temperature of about 100 °C to about 400 °C, and (b) Step of introducing a mixture of oxygen (O) and one or more inert gases, and (c) Step of performing pulsed DC reactive sputtering by applying a voltage to a second target to generate plasma, and

[0025] In one aspect of this embodiment, the disclosed and claimed PVD process includes Step 1 and Step 2. In one aspect of this embodiment, the disclosed and claimed PVD process consists essentially of Step 1 and Step 2. In one aspect of this embodiment, the disclosed and claimed PVD process consists of Step 1 and Step 2.

[0026] In one aspect of this embodiment, the first target includes one or more of a metal oxide material and a metal (i.e., elemental metal as opposed to a metal oxide). In one aspect of this embodiment, the first target and the second target are the same. In one aspect of this embodiment, the first target and the second target are different.

[0027] In one aspect of this embodiment, the first target includes a metal oxide material. In another aspect of this embodiment, the first target is SnO2 It includes a metal oxide material containing 2 It includes a metal oxide material containing 2 It includes a metal oxide material containing 2 It includes a metal oxide material containing

[0028] In one aspect of this embodiment, the first target contains a metal. In another aspect of this embodiment, the first target contains a metal selected from the group consisting of Sn, Ge, Ta, and Te. In another aspect of this embodiment, the first target contains a metal containing Sn. In another aspect of this embodiment, the first target contains a metal containing Ge. In another aspect of this embodiment, the first target contains a metal containing Ta. In another aspect of this embodiment, the first target contains Te. In another aspect of this embodiment, the first target contains a metal containing two or more of Sn, Ge, Ta, and Te. When the first target contains a metal, the reactive sputtering in step 1(c) utilizes a more oxygen-rich mixture compared to the oxygen mixture used for the first target containing the metal oxide material.

[0029] In one aspect of this embodiment, the second target contains one or more of a metal oxide material and a metal (i.e., elemental metal as opposed to metal oxide). In one aspect of this embodiment, the second target contains a metal oxide material. In another aspect of this embodiment, the second target contains 2 TiO. In one aspect of this embodiment, the second target contains a metal. In another aspect of this embodiment, the second target contains a metal containing Ti. When the second target contains a metal, the reactive sputtering in step 2(c) utilizes a more oxygen-rich mixture compared to the oxygen mixture used for the template layer containing the metal oxide material.

[0030] The disclosed and claimed PVD process includes Step 1 and Step 2.

[0031] In another aspect of this embodiment, the template layer includes SnO 2 In another aspect of this embodiment, the template layer includes GeO 2 In another aspect of this embodiment, the template layer includes TaO 2 In another aspect of this embodiment, the template layer includes TeO 2 In another aspect of this embodiment, the template layer includes SnO 2 GeO 2 TaO 2 and TeO 2 and includes two or more of them.

[0032] In another aspect of this embodiment, in one or both of Step 1(a) and Step 2(a), the substrate is set to a temperature of about 125°C to about 375°C. In another aspect of this embodiment, in one or both of Step 1(a) and Step 2(a), the substrate is set to a temperature of about 150°C to about 375°C. In another aspect of this embodiment, in one or both of Step 1(a) and Step 2(a), the substrate is set to a temperature of about 175°C to about 375°C. In another aspect of this embodiment, in one or both of Step 1(a) and Step 2(a), the substrate is set to a temperature of about 200°C to about 375°C. In another aspect of this embodiment, in one or both of Step 1(a) and Step 2(a), the substrate is set to a temperature of about 225°C to about 375°C. In another aspect of this embodiment, in one or both of Step 1(a) and Step 2(a), the substrate is set to a temperature of about 250°C to about 350°C. In another aspect of this embodiment, in one or both of Step 1(a) and Step 2(a), the substrate is set to a temperature of about 275°C to about 325°C.

[0033] In another aspect of this embodiment, in one or both of step 1(a) and step 2(a), the substrate is brought to a temperature of about 100°C. In another aspect of this embodiment, in one or both of step 1(a) and step 2(a), the substrate is brought to a temperature of about 125°C. In another aspect of this embodiment, in one or both of step 1(a) and step 2(a), the substrate is brought to a temperature of about 150°C. In another aspect of this embodiment, in one or both of step 1(a) and step 2(a), the substrate is brought to a temperature of about 175°C. In another aspect of this embodiment, in one or both of step 1(a) and step 2(a), the substrate is brought to a temperature of about 200°C. In another aspect of this embodiment, in one or both of step 1(a) and step 2(a), the substrate is brought to a temperature of about 225°C. In another aspect of this embodiment, in one or both of step 1(a) and step 2(a), the substrate is brought to a temperature of about 250°C. In another aspect of this embodiment, in one or both of step 1(a) and step 2(a), the substrate is brought to a temperature of about 275°C. In another aspect of this embodiment, in one or both of step 1(a) and step 2(a), the substrate is brought to a temperature of about 300°C. In another aspect of this embodiment, in one or both of step 1(a) and step 2(a), the substrate is brought to a temperature of about 325°C. In another aspect of this embodiment, in one or both of step 1(a) and step 2(a), the substrate is brought to a temperature of about 350°C. In another aspect of this embodiment, in one or both of step 1(a) and step 2(a), the substrate is brought to a temperature of about 375°C. In another aspect of this embodiment, in one or both of step 1(a) and step 2(a), the substrate is brought to a temperature of about 400°C.

[0034] In one aspect of this embodiment, step 1(a) and step 2(a) are performed at the same temperature. In one aspect of this embodiment, step 1(a) and step 2(a) are performed at substantially the same temperature. In one aspect of this embodiment, step 1(a) and step 2(a) are performed at different temperatures.

[0035] In another aspect of this embodiment, in one or both of step 1(b) and step 2(b), the inert gas contains argon (Ar). In another aspect of this embodiment, in one or both of step 1(b) and step 2(b), the inert gas contains nitrogen (N 2 ). In another aspect of this embodiment, in one or both of step 1(b) and step 2(b), the inert gas contains helium (He). In another aspect of this embodiment, in one or both of step 1(b) and step 2(b), the inert gas contains neon (Ne). In another aspect of this embodiment, the inert gas in step 1(b) is the same as the inert gas in step 2(b). In another aspect of this embodiment, the inert gas in step 1(b) is different from the inert gas in step 2(b).

[0036] In one embodiment, one or both of step 1(b) and step 2(b) are performed at a pressure of about 1 mTorr to about 10 mTorr. In one embodiment, one or both of step 1(b) and step 2(b) are performed at a pressure of about 1 mTorr to about 5 mTorr. In one embodiment, one or both of step 1(b) and step 2(b) are performed at a pressure of about 5 mTorr to about 10 mTorr. In one embodiment, one or both of step 1(b) and step 2(b) are performed at a pressure of about 3 mTorr to about 7 mTorr. In one embodiment, one or both of step 1(b) and step 2(b) are performed at a pressure of about 1 mTorr. In one embodiment, one or both of step 1(b) and step 2(b) are performed at a pressure of about 2 mTorr. In one embodiment, one or both of step 1(b) and step 2(b) are performed at a pressure of about 3 mTorr. In one embodiment, one or both of step 1(b) and step 2(b) are performed at a pressure of about 4 mTorr. In one embodiment, one or both of step 1(b) and step 2(b) are performed at a pressure of about 5 mTorr. In one embodiment, one or both of step 1(b) and step 2(b) are performed at a pressure of about 6 mTorr. In one embodiment, one or both of step 1(b) and step 2(b) are performed at a pressure of about 7 mTorr. In one embodiment, one or both of step 1(b) and step 2(b) are performed at a pressure of about 8 mTorr. In one embodiment, one or both of step 1(b) and step 2(b) are performed at a pressure of about 9 mTorr. In one embodiment, one or both of step 1(b) and step 2(b) are performed at a pressure of about 10 mTorr.

[0037] In one aspect of this embodiment, step 1(b) and step 2(b) are performed at the same pressure. In one aspect of this embodiment, step 1(b) and step 2(b) are performed at substantially the same pressure. In one aspect of this embodiment, step 1(b) and step 2(b) are performed at different pressures.

[0038] In another aspect of this embodiment, the template layer has a thickness of from about 15 Å to about 115 Å. In another aspect of this embodiment, the template layer has a thickness of from about 25 Å to about 100 Å. In another aspect of this embodiment, the template layer has a thickness of from about 25 Å to about 75 Å. In another aspect of this embodiment, the template layer has a thickness of from about 25 Å to about 65 Å. In another aspect of this embodiment, the template layer has a thickness of from about 25 Å to about 50 Å. In another aspect of this embodiment, the template layer has a thickness of from about 25 Å to about 35 Å. In another aspect of this embodiment, the template layer has a thickness of from about 15 Å to about 45 Å. In another aspect of this embodiment, the template layer has a thickness of from about 20 Å to about 40 Å.

[0039] In another aspect of this embodiment, the template layer has a thickness of about 10 Å. In another aspect of this embodiment, the template layer has a thickness of about 15 Å. In another aspect of this embodiment, the template layer has a thickness of about 20 Å. In another aspect of this embodiment, the template layer has a thickness of about 25 Å. In another aspect of this embodiment, the template layer has a thickness of about 30 Å. In another aspect of this embodiment, the template layer has a thickness of about 35 Å. In another aspect of this embodiment, the template layer has a thickness of about 40 Å. In another aspect of this embodiment, the template layer has a thickness of about 45 Å. In another aspect of this embodiment, the template layer has a thickness of about 50 Å. In another aspect of this embodiment, the template layer has a thickness of about 55 Å. In another aspect of this embodiment, the template layer has a thickness of about 60 Å. In another aspect of this embodiment, the template layer has a thickness of about 65 Å. In another aspect of this embodiment, the template layer has a thickness of about 70 Å. In another aspect of this embodiment, the template layer has a thickness of about 75 Å. In another aspect of this embodiment, the template layer has a thickness of about 80 Å. In another aspect of this embodiment, the template layer has a thickness of about 85 Å. In another aspect of this embodiment, the template layer has a thickness of about 90 Å. In another aspect of this embodiment, the template layer has a thickness of about 95 Å. In another aspect of this embodiment, the template layer has a thickness of about 100 Å. In another aspect of this embodiment, the template layer has a thickness of about 105 Å. In another aspect of this embodiment, the template layer has a thickness of about 110 Å. In another aspect of this embodiment, the template layer has a thickness of about 115 Å. In another aspect of this embodiment, the template layer has a thickness of about 120 Å. In another aspect of this embodiment, the template layer has a thickness of about 125 Å.

[0040] In another aspect of this embodiment, the voltage in step 1(c) for performing reactive sputtering is generated by DC. In another aspect of this embodiment, the voltage in step 1(c) for performing reactive sputtering is generated by RF.

[0041] In another aspect of this embodiment, the rutile TiO 2 high refractive index layer has a refractive index of about 2.70 to about 3.0 at 460 nm. In another aspect of this embodiment, the rutile TiO 2 high refractive index layer has a refractive index of about 2.75 to about 3.0 at 460 nm. In another aspect of this embodiment, the rutile TiO 2 high refractive index layer has a refractive index of about 2.80 to about 3.0 at 460 nm. In another aspect of this embodiment, the rutile TiO 2 high refractive index layer has a refractive index of about 2.85 to about 3.0 at 460 nm. In another aspect of this embodiment, the rutile TiO 2 high refractive index layer has a refractive index of about 2.90 to about 3.0 at 460 nm. In another aspect of this embodiment, the rutile TiO 2 high refractive index layer has a refractive index of about 2.95 to about 3.0 at 460 nm. In another aspect of this embodiment, the rutile TiO 2 high refractive index layer has a refractive index of about 2.70 to about 2.80 at 460 nm. In another aspect of this embodiment, the rutile TiO 2 high refractive index layer has a refractive index of about 2.70 to about 2.75 at 460 nm.

[0042] In another aspect of this embodiment, the rutile TiO 2 high refractive index layer has a refractive index of about 2.70 or more at 460 nm. In another aspect of this embodiment, the rutile TiO 2 high refractive index layer has a refractive index of about 2.75 or more at 460 nm. In another aspect of this embodiment, the rutile TiO 2 high refractive index layer has a refractive index of about 2.80 or more at 460 nm. In another aspect of this embodiment, the rutile TiO 2 high refractive index layer has a refractive index of about 2.85 or more at 460 nm. In another aspect of this embodiment, the rutile TiO 2 high refractive index layer has a refractive index of about 2.90 or more at 460 nm. In another aspect of this embodiment, the rutile TiO 2The high refractive index layer has a refractive index of about 2.95 or more at 460 nm. In another aspect of this embodiment, rutile TiO 2 The high refractive index layer has a refractive index of about 3.0 or more at 460 nm.

[0043] In another aspect of this embodiment, rutile TiO 2 The high refractive index layer has a refractive index of about 2.70 at 460 nm. In another aspect of this embodiment, rutile TiO 2 The high refractive index layer has a refractive index of about 2.75 at 460 nm. In another aspect of this embodiment, rutile TiO 2 The high refractive index layer has a refractive index of about 2.80 at 460 nm. In another aspect of this embodiment, rutile TiO 2 The high refractive index layer has a refractive index of about 2.85 at 460 nm. In another aspect of this embodiment, rutile TiO 2 The high refractive index layer has a refractive index of about 2.90 at 460 nm. In another aspect of this embodiment, rutile TiO 2 The high refractive index layer has a refractive index of about 2.95 at 460 nm. In another aspect of this embodiment, rutile TiO 2 The high refractive index layer has a refractive index of about 3.0 at 460 nm.

[0044] Suitable substrates that can use the disclosed and claimed processes are not particularly limited and vary depending on the intended end use. For example, the substrate can be selected from transition metal oxides, rare earth oxide-based materials, ternary oxide-based materials, etc., or from nitride-based films. Other substrates include solid substrates such as metal substrates (e.g., Au, Pd, Rh, Ru, W, Al, Ni, Ti, Co, Pt, and metal silicides (TiSi 2 CoSi 2 and NiSi 2 etc.), metal nitride-containing substrates (e.g., TaN, TiN, WN, TaCN, TiCN, TaSiN, and TiSiN), semiconductor materials (e.g., Si, SiGe, GaAs, InP, diamond, GaN, and SiC), insulators (e.g., SiO 2 Si 3 N 4 SiON, HfO 2, Ta 2 O 5 , ZrO 2 , TiO 2 , Al 2 O 3 , barium strontium titanate, plastic, and a flexible substrate (e.g., a polymer), and combinations thereof. Preferred substrates include glass and silicon oxide-based substrates. In one embodiment, the substrate comprises glass. In another embodiment, the substrate comprises a silicon oxide-based material.

Examples

[0045] (Example)

[0046] Here, reference is made to more specific embodiments of the present disclosure and experimental results supporting such embodiments. The following examples are intended to more fully illustrate the disclosed and claimed subject matter and should in no way be construed as limiting the disclosed subject matter.

[0047] It will be apparent to those skilled in the art that various modifications and variations can be made to the disclosed subject matter and the specific examples provided herein without departing from the spirit and scope of the disclosed subject matter. Accordingly, the disclosed subject matter, including the description provided by the following examples, is intended to cover modifications and variations of the disclosed subject matter that fall within the scope of any claim and their equivalents.

[0048] Materials and Methods:

[0049] All experiments described in the examples were performed in a PVD sputtering chamber having a base pressure of 1E - 7 mTorr. The chamber is equipped with two or more targets to enable the deposition of multiple layers without breaking the vacuum. A mixture of gases (O, Ar, etc.) can be introduced into the chamber during the process. The pedestal temperature can be adjusted between room temperature and 600 °C. Finally, the voltage can be applied continuously (DC), pulsed (PDC), or at an RF frequency to different targets.

[0050] Specific example

[0051] Example 1: As shown in Table 1, for different stacks deposited at different temperatures, with or without using a template layer, different refractive index values are obtained. Notably, when deposited without using a template layer, due to the lack of crystallinity for deposition temperatures up to 350 °C, no crystal peaks are detected for TiO using X-ray diffraction (XRD). In contrast, the introduction of a template layer promotes the crystal growth of TiO starting at a deposition temperature of about 150 °C and increases the refractive index to 2.81 at 460 nm when deposited at 350 °C. 2 For different stacks deposited at different temperatures, with or without using a template layer, different refractive index values are obtained. Notably, when deposited without using a template layer, due to the lack of crystallinity for deposition temperatures up to 350 °C, no crystal peaks are detected for TiO using X-ray diffraction (XRD). In contrast, the introduction of a template layer promotes the crystal growth of TiO starting at a deposition temperature of about 150 °C and increases the refractive index to 2.81 at 460 nm when deposited at 350 °C. 2 When deposited without using a template layer, due to the lack of crystallinity for deposition temperatures up to 350 °C, no crystal peaks are detected for TiO using X-ray diffraction (XRD). In contrast, the introduction of a template layer promotes the crystal growth of TiO starting at a deposition temperature of about 150 °C and increases the refractive index to 2.81 at 460 nm when deposited at 350 °C. 2 When deposited without using a template layer, due to the lack of crystallinity for deposition temperatures up to 350 °C, no crystal peaks are detected for TiO using X-ray diffraction (XRD). In contrast, the introduction of a template layer promotes the crystal growth of TiO starting at a deposition temperature of about 150 °C and increases the refractive index to 2.81 at 460 nm when deposited at 350 °C. 2 The introduction of a template layer promotes the crystal growth of TiO starting at a deposition temperature of about 150 °C and increases the refractive index to 2.81 at 460 nm when deposited at 350 °C. 2 The introduction of a template layer promotes the crystal growth of TiO starting at a deposition temperature of about 150 °C and increases the refractive index to 2.81 at 460 nm when deposited at 350 °C. [Table 2]

[0052] Example 2: As shown in Table 2, in order to increase and / or adjust the refractive index of the deposited TiO (the second layer), adjustments to the process parameters can be made. This is demonstrated for the process parameters and results obtained when depositing TiO at 350 °C using a SnO (the first layer) template layer with a thickness of 30 - 100 Å (deposited at 350 °C). Both the first and second layer processes were carried out using an argon flow of 12 sccm. The highest refractive index was obtained with a SnO thickness of 50 Å. Figure 1 shows the XRD scans corresponding to the same samples showing rutile TiO growth in all cases. 2 (The second layer) In order to increase and / or adjust the refractive index of the deposited TiO, adjustments to the process parameters can be made. This is demonstrated for the process parameters and results obtained when depositing TiO at 350 °C using a SnO (the first layer) template layer with a thickness of 30 - 100 Å (deposited at 350 °C). Both the first and second layer processes were carried out using an argon flow of 12 sccm. The highest refractive index was obtained with a SnO thickness of 50 Å. Figure 1 shows the XRD scans corresponding to the same samples showing rutile TiO growth in all cases. 2 (The first layer) template layer (deposited at 350 °C) and depositing TiO at 350 °C. 2 This is demonstrated for the process parameters and results obtained when depositing TiO at 350 °C using a SnO (the first layer) template layer with a thickness of 30 - 100 Å (deposited at 350 °C). Both the first and second layer processes were carried out using an argon flow of 12 sccm. The highest refractive index was obtained with a SnO thickness of 50 Å. Figure 1 shows the XRD scans corresponding to the same samples showing rutile TiO growth in all cases. 2 The highest refractive index was obtained with a SnO thickness of 50 Å. Figure 1 shows the XRD scans corresponding to the same samples showing rutile TiO growth in all cases. 2 The highest refractive index was obtained with a SnO thickness of 50 Å. Figure 1 shows the XRD scans corresponding to the same samples showing rutile TiO growth in all cases. [Table 3]

[0053] The foregoing description is primarily for illustrative purposes. Although the disclosed and claimed subject matter has been shown and described with respect to its exemplary embodiments, it should be understood by those skilled in the art that various other changes, omissions, and additions in its form and details may be made without departing from the spirit and scope of the disclosed and claimed subject matter.

Claims

1. A PVD process, comprising: (1) Using a first target, depositing a template layer containing one or more of metal oxides selected from the group of SnO ２ , GeO ２ , TaO ２ , TeO ２ on the substrate surface, the following steps, (a) heating the substrate to a temperature of about 100°C to about 400°C; (b) introducing a mixture of oxygen (O) and one or more inert gases; (c) performing pulsed DC reactive sputtering by applying a voltage to the first target to generate a plasma; depositing a template layer having a thickness of about 10 Å to about 125 Å; (2) Depositing a rutile TiO high refractive index layer on the template layer using the second target, comprising the following steps: ２ (2) Depositing a rutile TiO high refractive index layer on the template layer using the second target, comprising the following steps: (a) heating the substrate to a temperature of about 100°C to about 400°C; (b) introducing a mixture of oxygen (O) and one or more inert gases; (c) performing pulsed DC reactive sputtering by applying a voltage to the second target to generate a plasma; depositing a high refractive index layer;

2. The template layer is SnO ２ , GeO ２ , TaO ２ , TeO ２ and a metal oxide selected from the group consisting of combinations thereof, the PVD process according to claim 1.

3. The template layer is SnO ２ , GeO ２ , TaO ２ and TeO ２ The PVD process according to claim 1, comprising two or more of them.

4. The template layer contains SnO ２ The PVD process according to claim 1, which contains ２ .

5. The template layer is GeO ２ The PVD process according to claim 1, comprising

6. The template layer is TaO ２ The PVD process according to claim 1, comprising ２ .

7. The template layer is TeO ２ The PVD process according to claim 1, comprising

8. The PVD process according to claim 1, wherein the first target comprises one or more of a metal oxide material and a metal.

9. The PVD process according to claim 1, wherein the first target and the second target are the same.

10. The PVD process according to claim 1, wherein the first target and the second target are different.

11. The PVD process according to claim 1, wherein the first target comprises a metal oxide material.

12. wherein the first target comprises a metal oxide material containing SnO ２ The PVD process according to claim 1, wherein the metal oxide material contains

13. The first target includes a metal oxide material containing GeO ２ The PVD process according to claim 1, wherein the metal oxide material contains GeO

14. wherein the first target includes a metal oxide material containing TaO ２ The PVD process according to claim 1, wherein the metal oxide material contains TaO

15. The first target includes a metal oxide material containing TeO ２ The PVD process according to claim 1, wherein the metal oxide material contains ２ .

16. The PVD process according to claim 1, wherein the first target comprises a metal.

17. The PVD process according to claim 1, wherein the first target comprises a metal selected from the group consisting of Sn, Ge, Ta, and Te.

18. The PVD process according to claim 1, wherein the first target comprises a metal containing Sn.

19. The PVD process according to claim 1, wherein the first target comprises a metal containing Ge.

20. The PVD process according to claim 1, wherein the first target comprises a metal containing Ta.

21. The PVD process according to claim 1, wherein the first target comprises a metal containing Te.

22. The PVD process according to claim 1, wherein the first target comprises a metal containing two or more of Sn, Ge, Ta, and Te.

23. The PVD process according to claim 1, wherein the second target comprises one or more of a metal oxide material and a metal.

24. The PVD process according to claim 1, wherein the second target comprises a metal oxide material.

25. The second target includes a metal oxide material containing TiO ２ The PVD process according to claim 1, wherein the second target includes a metal oxide material containing TiO

26. The PVD process according to claim 1, wherein the second target comprises a metal.

27. The PVD process according to claim 1, wherein the second target comprises a metal containing Ti.

28. The PVD process according to claim 1, wherein in one or both of step 1(a) and step 2(a), the substrate is at a temperature of about 125°C to about 375°C.

29. The PVD process according to claim 1, wherein in one or both of step 1(a) and step 2(a), the substrate is at a temperature of about 150°C to about 375°C.

30. The PVD process according to claim 1, wherein in one or both of step 1(a) and step 2(a), the substrate is at a temperature of about 175°C to about 375°C.

31. The PVD process according to claim 1, wherein in one or both of step 1(a) and step 2(a), the substrate is at a temperature of about 200°C to about 375°C.

32. The PVD process according to claim 1, wherein in one or both of step 1(a) and step 2(a), the substrate is at a temperature of about 225°C to about 375°C.

33. The PVD process according to claim 1, wherein in one or both of step 1(a) and step 2(a), the substrate is at a temperature of about 250°C to about 350°C.

34. The PVD process according to claim 1, wherein in one or both of step 1(a) and step 2(a), the substrate is at a temperature of about 275°C to about 325°C.

35. The PVD process according to claim 1, wherein in one or both of step 1(a) and step 2(a), the substrate is at a temperature of about 100°C.

36. The PVD process according to claim 1, wherein in one or both of step 1(a) and step 2(a), the substrate is at a temperature of about 125°C.

37. The PVD process according to claim 1, wherein in one or both of step 1(a) and step 2(a), the substrate is at a temperature of about 150°C.

38. The PVD process according to claim 1, wherein in one or both of step 1(a) and step 2(a), the substrate is brought to a temperature of about 175°C.

39. The PVD process according to claim 1, wherein in one or both of step 1(a) and step 2(a), the substrate is brought to a temperature of about 200°C.

40. The PVD process according to claim 1, wherein in one or both of step 1(a) and step 2(a), the substrate is brought to a temperature of about 225°C.

41. The PVD process according to claim 1, wherein in one or both of step 1(a) and step 2(a), the substrate is brought to a temperature of about 250°C.

42. The PVD process according to claim 1, wherein in one or both of step 1(a) and step 2(a), the substrate is brought to a temperature of about 275°C.

43. The PVD process according to claim 1, wherein in one or both of step 1(a) and step 2(a), the substrate is brought to a temperature of about 300°C.

44. The PVD process according to claim 1, wherein in one or both of step 1(a) and step 2(a), the substrate is brought to a temperature of about 325°C.

45. The PVD process according to claim 1, wherein in one or both of step 1(a) and step 2(a), the substrate is brought to a temperature of about 350°C.

46. The PVD process according to claim 1, wherein in one or both of step 1(a) and step 2(a), the substrate is brought to a temperature of about 375°C.

47. The PVD process according to claim 1, wherein in one or both of step 1(a) and step 2(a), the substrate is brought to a temperature of about 400°C.

48. The PVD process according to claim 1, wherein step 1(a) and step 2(a) are performed at the same temperature.

49. The PVD process according to claim 1, wherein step 1(a) and step 2(a) are performed at substantially the same temperature.

50. The PVD process according to claim 1, wherein step 1(a) and step 2(a) are performed at different temperatures.

51. The PVD process according to claim 1, wherein in one or both of step 1(b) and step 2(b), the inert gas contains argon (Ar).

52. In one or both of Step 1(b) and Step 2(b), the inert gas contains nitrogen (N ２ ), the PVD process according to claim 1.

53. The PVD process according to claim 1, wherein in one or both of step 1(b) and step 2(b), the inert gas contains helium (He).

54. The PVD process according to claim 1, wherein in one or both of step 1(b) and step 2(b), the inert gas contains neon (Ne).

55. The PVD process according to claim 1, wherein the inert gas in step 1(b) is the same as the inert gas in step 2(b).

56. The PVD process according to claim 1, wherein the inert gas in step 1(b) is different from the inert gas in step 2(b).

57. The PVD process according to claim 1, wherein one or both of step 1(b) and step 2(b) are carried out at a pressure of about 1 mTorr to about 10 mTorr.

58. The PVD process according to claim 1, wherein one or both of step 1(b) and step 2(b) are carried out at a pressure of about 1 mTorr to about 5 mTorr.

59. The PVD process according to claim 1, wherein one or both of step 1(b) and step 2(b) are carried out at a pressure of about 5 mTorr to about 10 mTorr.

60. The PVD process according to claim 1, wherein one or both of step 1(b) and step 2(b) are carried out at a pressure of about 3 mTorr to about 7 mTorr.

61. The PVD process according to claim 1, wherein one or both of step 1(b) and step 2(b) are carried out at a pressure of about 1 mTorr.

62. The PVD process according to claim 1, wherein one or both of step 1(b) and step 2(b) are carried out at a pressure of about 2 mTorr.

63. The PVD process according to claim 1, wherein one or both of step 1(b) and step 2(b) are carried out at a pressure of about 3 mTorr.

64. The PVD process according to claim 1, wherein one or both of step 1(b) and step 2(b) are carried out at a pressure of about 4 mTorr.

65. The PVD process according to claim 1, wherein one or both of step 1(b) and step 2(b) are carried out at a pressure of about 5 mTorr.

66. The PVD process according to claim 1, wherein one or both of step 1(b) and step 2(b) are carried out at a pressure of about 6 mTorr.

67. The PVD process according to claim 1, wherein one or both of step 1(b) and step 2(b) are performed at a pressure of about 7 mTorr.

68. The PVD process according to claim 1, wherein one or both of step 1(b) and step 2(b) are performed at a pressure of about 8 mTorr.

69. The PVD process according to claim 1, wherein one or both of step 1(b) and step 2(b) are performed at a pressure of about 9 mTorr.

70. The PVD process according to claim 1, wherein one or both of step 1(b) and step 2(b) are performed at a pressure of about 10 mTorr.

71. The PVD process according to claim 1, wherein step 1(b) and step 2(b) are performed at the same pressure.

72. The PVD process according to claim 1, wherein step 1(b) and step 2(b) are performed at substantially the same pressure.

73. The PVD process according to claim 1, wherein step 1(b) and step 2(b) are performed at different pressures.

74. The PVD process according to claim 1, wherein the template layer has a thickness of about 15 Å to about 115 Å.

75. The PVD process according to claim 1, wherein the template layer has a thickness of about 25 Å to about 100 Å.

76. The PVD process according to claim 1, wherein the template layer has a thickness of about 25 Å to about 75 Å.

77. The PVD process according to claim 1, wherein the template layer has a thickness of about 25 Å to about 65 Å.

78. The PVD process according to claim 1, wherein the template layer has a thickness of about 25 Å to about 50 Å.

79. The PVD process according to claim 1, wherein the template layer has a thickness of about 25 Å to about 35 Å.

80. The PVD process according to claim 1, wherein the template layer has a thickness of about 15 Å to about 45 Å.

81. The PVD process according to claim 1, wherein the template layer has a thickness of about 20 Å to about 40 Å.

82. The PVD process according to claim 1, wherein the template layer has a thickness of about 10 Å.

83. The PVD process according to claim 1, wherein the template layer has a thickness of about 15 Å.

84. The PVD process according to claim 1, wherein the template layer has a thickness of about 20 Å.

85. The PVD process according to claim 1, wherein the template layer has a thickness of about 25 Å.

86. The PVD process according to claim 1, wherein the template layer has a thickness of about 30 Å.

87. The PVD process according to claim 1, wherein the template layer has a thickness of about 35 Å.

88. The PVD process according to claim 1, wherein the template layer has a thickness of about 40 Å.

89. The PVD process according to claim 1, wherein the template layer has a thickness of about 50 Å.

90. The PVD process according to claim 1, wherein the template layer has a thickness of about 55 Å.

91. The PVD process according to claim 1, wherein the template layer has a thickness of about 60 Å.

92. The PVD process according to claim 1, wherein the template layer has a thickness of about 65 Å.

93. The PVD process according to claim 1, wherein the template layer has a thickness of about 70 Å.

94. The PVD process according to claim 1, wherein the template layer has a thickness of about 75 Å.

95. The PVD process according to claim 1, wherein the template layer has a thickness of about 80 Å.

96. The PVD process according to claim 1, wherein the template layer has a thickness of about 85 Å.

97. The PVD process according to claim 1, wherein the template layer has a thickness of about 90 Å.

98. The PVD process according to claim 1, wherein the template layer has a thickness of about 95 Å.

99. The PVD process according to claim 1, wherein the template layer has a thickness of about 100 Å.

100. The PVD process according to claim 1, wherein the template layer has a thickness of about 105 Å.

101. The PVD process according to claim 1, wherein the template layer has a thickness of about 110 Å.

102. The PVD process according to claim 1, wherein the template layer has a thickness of about 115 Å.

103. The PVD process according to claim 1, wherein the template layer has a thickness of about 120 Å.

104. The PVD process according to claim 1, wherein the template layer has a thickness of about 125 Å.

105. The rutile TiO ２ PVD process according to claim 1, wherein the high refractive index layer has a refractive index of about 2.70 to about 3.0 at 460 nm.

106. The rutile TiO ２ The PVD process according to claim 1, wherein the high refractive index layer has a refractive index of about 2.75 to about 3.0 at 460 nm.

107. The rutile TiO ２ The PVD process according to claim 1, wherein the high refractive index layer of ２ has a refractive index of about 2.80 to about 3.0 at 460 nm.

108. The rutile TiO ２ PVD process according to claim 1, wherein the high refractive index layer has a refractive index of about 2.85 to about 3.0 at 460 nm.

109. The rutile TiO ２ The PVD process according to claim 1, wherein the high refractive index layer of ２ has a refractive index of about 2.90 to about 3.0 at 460 nm.

110. The rutile TiO ２ PVD process according to claim 1, wherein the high refractive index layer has a refractive index of about 2.95 to about 3.0 at 460 nm.

111. The rutile TiO ２ The PVD process according to claim 1, wherein the high refractive index layer has a refractive index of about 2.70 to about 2.80 at 460 nm.

112. The rutile TiO ２ The PVD process according to claim 1, wherein the high refractive index layer has a refractive index of about 2.70 to about 2.75 at 460 nm.

113. The rutile TiO ２ PVD process according to claim 1, wherein the high refractive index layer has a refractive index of about 2.70 or more at 460 nm.

114. The rutile TiO ２ The PVD process according to claim 1, wherein the high refractive index layer has a refractive index of about 2.75 or more at 460 nm.

115. The rutile TiO ２ The PVD process according to claim 1, wherein the high refractive index layer has a refractive index of about 2.80 or more at 460 nm.

116. The rutile TiO ２ The PVD process according to claim 1, wherein the high refractive index layer of ２ has a refractive index of about 2.85 or more at 460 nm.

117. The rutile TiO ２ The PVD process according to claim 1, wherein the high refractive index layer has a refractive index of about 2.90 or more at 460 nm.

118. The rutile TiO ２ The PVD process according to claim 1, wherein the high refractive index layer of ２ has a refractive index of about 2.95 or more at 460 nm.

119. The rutile TiO ２ The PVD process according to claim 1, wherein the high refractive index layer has a refractive index of about 3.0 or more at 460 nm.

120. The rutile TiO ２ The PVD process according to claim 1, wherein the high refractive index layer has a refractive index of about 2.70 at 460 nm.

121. The rutile TiO ２ The PVD process according to claim 1, wherein the high refractive index layer has a refractive index of about 2.75 at 460 nm.

122. The rutile TiO ２ The PVD process according to claim 1, wherein the high refractive index layer has a refractive index of about 2.80 at 460 nm.

123. The rutile TiO ２ PVD process according to claim 1, wherein the high refractive index layer has a refractive index of about 2.85 at 460 nm.

124. The rutile TiO ２ PVD process according to claim 1, wherein the high refractive index layer has a refractive index of about 2.90 at 460 nm.

125. The rutile TiO ２ The PVD process according to claim 1, wherein the high refractive index layer has a refractive index of about 2.95 at 460 nm.

126. The rutile TiO ２ The PVD process according to claim 1, wherein the high refractive index layer has a refractive index of about 3.0 at 460 nm.

127. The PVD process according to claim 1, wherein the substrate comprises one or more of a transition metal oxide, a rare earth oxide-based material, a ternary oxide-based material, and a nitride-based material.

128. The PVD process according to claim 1, wherein the substrate comprises one or more of a solid metal substrate and a metal silicide.

129. The PVD process according to claim 1, wherein the substrate comprises a metal substrate containing one or more of Au, Pd, Rh, Ru, W, Al, Ni, Ti, Co, and Pt.

130. The substrate is TiSi ２ , CoSi ２ and NiSi ２ The PVD process according to claim 1, comprising a metal silicide containing one or more of them.

131. The PVD process according to claim 1, wherein the substrate comprises glass.

132. The PVD process according to claim 1, wherein the substrate comprises a silicon oxide-based material.

133. The PVD process according to claim 1, wherein the substrate comprises one or more of a semiconductor material and an insulator.

134. The PVD process according to claim 1, wherein the substrate comprises a semiconductor material containing one or more of Si, SiGe, GaAs, InP, diamond, GaN, and SiC.

135. The substrate is SiO ２ , Si ３ N ４ , SiON, HfO ２ , Ta ２ O ５ , ZrO ２ , TiO ２ , Al ２ O ３ The PVD process according to claim 1, comprising an insulator containing one or more of barium strontium titanate.

136. The PVD process according to claim 1, wherein the substrate comprises one or more of a plastic and a flexible substrate.

137. The PVD process according to claim 1, wherein the substrate comprises one or more flexible substrates containing a polymer.

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