Manufacturing method of electrochromic element

Abstract

SOLUTION: In an electrochromic element pertaining to a prior art, there are often many problems of low reliability and performance. These problems partially occur because the design and structure of the electrochromic element are inappropriate. For increasing reliability of the electrochromic element, two of a counter electrode layer and an electrochromic layer from among layers for constituting the electrochromic layer are manufactured so as to contain a predetermined amount of lithium. For increasing performance of the electrochromic element, multistage thermochemical adjustment treatment may be executed. Also, performance and reliability are improved by carefully selecting partial materials and forms of components of the electrochromic element. In some electrochromic elements, all the layers are completely formed from a solid and an inorganic material.SELECTED DRAWING: Figure 7A

Description

[Technical field]

[0001] [Background technology] This application claims priority to U.S. Provisional Patent Application No. 61 / 165,484, filed March 31, 2009, and U.S. Patent Application No. 12 / 645,159, filed December 22, 2009, the entire contents of both of which are incorporated herein by reference. [Background technology]

[0002] Electrochromism is the electrochemically mediated reversible change in the optical properties of a material when the electronic state of the material is changed, usually by a change in voltage. The optical properties usually refer to one or more of color, transmittance, absorbance, and reflectance. One well-known electrochromic material is tungsten oxide (WO3). Tungsten oxide is a cathodic electrochromic material that changes color from clear to blue upon electrochemical reduction.

[0003] Electrochromic materials can be used, for example, in windows and mirrors. In this case, the color, transmittance, absorbance and / or reflectance of the windows and mirrors can be changed by changing the electrochromic material. A well-known example of the use of electrochromic materials is the rearview mirror of an automobile. In the case of such rearview mirrors using electrochromic materials, the reflectance of the mirror changes at night to prevent the headlights of other vehicles from bothering the driver.

[0004] Although electrochromism was discovered in the 1960s, electrochromic devices still suffer from a variety of problems that have prevented them from realizing their full commercial potential. Summary of the Invention [Problem to be solved by the invention]

[0005] The inventors have noted that prior art electrochromic devices often suffer from poor reliability and performance problems. Some of these problems are due to improper device design and construction. The inventors have discovered that device reliability can be improved by fabricating two of the layers of the electrochromic device, the counter electrode layer and the electrochromic layer, to contain a predetermined amount of lithium, among other features described herein. The electrochromic device can also be improved in performance by undergoing a multi-step thermochemical conditioning process. Furthermore, performance and reliability can be improved by carefully selecting the materials and morphology of some of the components of the electrochromic device. In some embodiments, all layers of the electrochromic device are entirely solid and inorganic materials. [Means for solving the problem]

[0006] In one embodiment, an electrochromic window comprises an architectural glass substrate and a laminate disposed on the substrate, the laminate having (i) an electrochromic layer of tungsten oxide, (ii) a lithium ion conductor layer of a solid inorganic material, and (iii) a counter electrode layer of tungsten nickel oxide, the ion conductor layer separating the electrochromic layer and the counter electrode layer.

[0007] In one embodiment, an electrochromic device is fabricated on a substrate by (a) depositing an electrochromic layer, (b) lithiating the electrochromic layer, (c) depositing an ion conductor layer, (d) depositing a counter electrode layer that reversibly exchanges lithium ions with the electrochromic layer upon operation of the electrochromic window, and (e) lithiating the counter electrode layer, producing a laminate on the substrate in which the ion conductor layer separates the electrochromic layer and the counter electrode layer.

[0008] In another embodiment, an electrochromic window includes an architectural glass substrate and a laminate disposed on the substrate, the laminate having (i) an electrochromic layer of tungsten oxide, (ii) a lithium ion conductor layer of a solid, inorganic material, and (iii) a counter electrode layer of substantially amorphous tungsten nickel oxide, the ion conductor layer separating the electrochromic layer and the counter electrode layer.

[0009] In another embodiment, an electrochromic window is fabricated by sequentially depositing on a substrate: (i) an electrochromic layer of tungsten oxide, (ii) a lithium ion conductor layer of an inorganic, solid-state material, and (iii) a counter electrode layer of substantially amorphous tungsten nickel oxide, forming a stack of layers with the ion conductor layer separating the electrochromic layer and the counter electrode layer.

[0010] In yet another embodiment, an electrochromic window is fabricated by sequentially depositing on a substrate (i) an electrochromic layer of a solid, inorganic material, (ii) an ionically conductive layer of a solid, inorganic material, and (iii) a counter electrode layer of a solid, inorganic material, forming a stack with the ionically conductive layer separating the electrochromic layer and the counter electrode layer, followed by a multi-step thermochemical conditioning process that includes heating the stack in an environment substantially free of components that react with one or more layers of the stack, and heating the stack in an environment that includes a material that reacts with one or more layers of the stack.

[0011] These and other features and advantages of the present invention will be described in more detail below with reference to the associated drawings. [Brief description of the drawings]

[0012] The following detailed description can be better understood with reference to the drawings, in which: [Figure 1]1 is a schematic diagram showing a cross section of an electrochromic element according to an embodiment of the present invention. [Diagram 2] FIG. 2 is a schematic diagram showing a cross-section of an electrochromic element in a bleached state, according to certain embodiments of the present invention. [Diagram 3] FIG. 2 is a schematic diagram showing a cross-section of an electrochromic element in a colored state, according to certain embodiments of the present invention. [Figure 4] FIG. 1 is a schematic diagram showing a cross-section of an electrochromic device having a localized defect caused by a particle in the ion-conducting layer. [Figure 5A] FIG. 2 is a schematic diagram showing a cross-section of an electrochromic element with remaining particles on the conductive layer prior to deposition of the remaining layers of the electrochromic stack. [Figure 5B] FIG. 5B is a schematic diagram showing a cross-section of the electrochromic device of FIG. 5A, where a "pop-off" defect is formed during formation of the electrochromic stack. [Figure 5C] FIG. 5C is a schematic diagram showing a cross-section of the electrochromic device of FIG. 5B illustrating the formation of an electrical short from a pop-off defect when a second conductor is deposited. [Figure 6A] FIG. 7B is a cross-sectional view showing an electrochromic window device obtained by the multi-step process described with reference to FIG. 7A. [Figure 6B] FIG. 2 is a top view of an electrochromic element showing the location of trenches cut into the electrochromic element. [Figure 7A] 1 is a flow chart illustrating a method of manufacturing an electrochromic window. [Figure 7B] 1A to 1C are diagrams illustrating a method for manufacturing an electrochromic stack that forms part of an electrochromic device according to the present invention. [Figure 7C] 1A to 1C are diagrams illustrating a method for manufacturing an electrochromic stack that forms part of an electrochromic device according to the present invention. [Figure 7D]1A to 1C are diagrams illustrating a method for manufacturing an electrochromic stack that forms part of an electrochromic device according to the present invention. [Figure 7E] 4 is a flow chart illustrating a conditioning process used to manufacture an electrochromic device according to the present invention. [Figure 8A] FIG. 1 illustrates a total synthetic membrane system according to the present invention. [Figure 8B] FIG. 1 is a perspective view showing a total synthetic membrane system. [Figure 8C] FIG. 1 illustrates a modular, total synthetic membrane system. [Figure 8D] FIG. 1 shows a total synthesis film system having two lithium deposition stations. [Figure 8E] FIG. 1 shows a total synthesis film system having one lithium deposition station. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] <Electrochromic element> A cross-section of an electrochromic device 100 according to some embodiments is shown in schematic form in FIG. 1. The electrochromic device includes a substrate 102, a conductive layer (CL) 104, an electrochromic layer (EC) 106, an ion-conductive layer (IC) 108, a counter electrode layer (CE) 110, and a conductive layer (CL) 114. The components 104, 106, 108, 110, and 114 are collectively referred to as an electrochromic stack 120. A voltage source 116 applies a potential to the electrochromic stack 120, for example, changing the electrochromic device from a bleached state to a colored state. In other embodiments, the order of the constituent layers is reversed with respect to the substrate, that is, the order is substrate, conductive layer, counter electrode layer, ion-conductive layer, electrochromic material layer, and conductive layer.

[0014] It should be understood that the term "change between a bleached state and a colored state" is not intended to be limiting, but merely provides one example of many possible electrochromic changes. Unless otherwise stated herein, the term "bleached-colored change" refers to other optical state changes, such as non-reflective-reflective, transparent-opaque, etc., corresponding elements or processes. The term "bleached" also refers to an optically achromatic state, such as colorless, transparent, or translucent. Furthermore, unless otherwise stated herein, the "color" of the electrochromic change is not limited to a particular wavelength or wavelength range. As will be appreciated by those skilled in the art, the type of optical change that occurs is determined by the selection of appropriate electrochromic material and counter electrode materials.

[0015] In certain embodiments, the electrochromic element reversibly changes state between a bleached state and a colored state. In the bleached state, an electrical potential is applied to the electrochromic stack 120 such that available ions in the stack capable of causing the electrochromic material 106 to become colored are primarily present in the counter electrode 110. When the electrical potential applied to the electrochromic stack is reversed, the ions are transported through the ion conducting layer 108 to the electrochromic material 106, causing the electrochromic material to become colored. The transition from the bleached state to the colored state and back is described in more detail below with reference to Figures 2 and 3, but first the layers of the stack 120 are described in more detail with reference to Figure 1.

[0016] In certain embodiments, all of the materials making up the electrochromic stack 120 are inorganic, solid (i.e., in a solid state), or both inorganic and solid. Since organic materials tend to degrade over time, inorganic materials have the advantage of providing a reliable electrochromic stack that can be used for a long period of time. Solid-state materials also have the advantage of not having the containment and leakage issues that liquid-state materials often have. Each of the layers making up the electrochromic element is described in detail below. It should be understood that while any one or more of the layers making up the stack may contain some organic material, in many embodiments, one or more of these layers will contain little or no organic material. The same is true for liquids, where one or more layers may contain small amounts of liquid. It should also be understood that the solid-state materials may be deposited or otherwise formed by processes utilizing liquid components, such as sol-gel processes, or chemical vapor deposition.

[0017] 1, the voltage source 116 is typically a low voltage power source and may operate in conjunction with radiation and other environmental sensors. The voltage source 116 may further be configured to interface with an energy management system, such as a computer system, that controls the electrochromic elements depending on the season, time of day, and measured environmental conditions. Such an energy management system, when used in conjunction with large area electrochromic elements (i.e., electrochromic windows), can significantly reduce the energy consumption of a building.

[0018] The substrate 102 may be a material having suitable optical, electrical, thermal and mechanical properties. Examples of such substrates include glass, plastic and mirror materials. Examples of suitable plastic substrates include acrylic, polystyrene, polycarbonate, allyl diglycol carbonate, SAN (styrene acrylonitrile copolymer), poly(4-methyl-1-pentene), polyester, polyamide, etc. If a plastic substrate is used, it is preferable to provide a barrier and abrasion protection using a hard coat, for example, a diamond-like protective coating, a silica / silicone abrasion resistant coating, etc., as known in the plastic coating art. Suitable glasses include clear or tinted soda lime glass, including soda lime float glass. The glass may be tempered or untempered. For example, in some embodiments of the electrochromic element 100 that use glass, such as soda-lime glass, as the substrate 102, there is a sodium diffusion barrier layer (not shown) between the substrate 102 and the conductive layer 104 to prevent diffusion of sodium ions from the glass into the conductive layer 104.

[0019] In some embodiments, the optical transmittance of the substrate 102 (i.e., the ratio of transmitted radiation or spectrum to incident radiation or spectrum) is about 40% to 95%, such as about 90% to 92%. The substrate may be of any thickness so long as it has suitable mechanical properties to support the electrochromic stack 120. The substrate 102 may be of any dimension, but in some embodiments has a thickness of about 0.01 mm to 10 mm, preferably about 3 mm to 9 mm.

[0020] In some embodiments of the invention, the substrate is architectural glass. Architectural glass is glass used as a building material. Architectural glass is typically used in commercial construction, but may also be used in residential construction, and typically, but not necessarily, serves to separate indoor and outdoor spaces. In certain embodiments, architectural glass is at least 20 inches by 20 inches in size, and may be much larger, for example, up to about 72 inches by 120 inches. Architectural glass is typically at least about 2 mm thick. Architectural glass with a thickness of less than about 3.2 mm cannot be tempered. In some embodiments of the invention using architectural glass as a substrate, the substrate may be further tempered even after the electrochromic stack is fabricated on the substrate. In some embodiments using architectural glass as a substrate, the substrate is soda lime glass obtained from a tin-based float glass manufacturing line. The transmittance of architectural glass substrates in the visible spectrum (i.e., the total transmittance across the visible spectrum) is typically greater than 80% for neutral substrates, but may be lower for tinted substrates. The transmittance of the substrate in the visible spectrum is preferably at least about 90% (e.g., about 90-92%). The visible spectrum is the spectrum to which the normal human eye responds, typically from about 380 nm (violet) to about 780 nm (red). In some cases, the roughness of the glass surface may be about 10 nm to 30 nm.

[0021] A conductive layer 104 is provided on the substrate 102. In certain embodiments, one or both of the conductive layers 104 and 114 are inorganic and / or solid materials. The conductive layers 104 and 114 may be formed of a number of different materials, including conductive oxides, thin metallic coatings, conductive metal nitrides, and mixed conductors. The conductive layers 104 and 114 are typically transparent, at least in the wavelength range in which the electrochromism of the electrochromic layer is observed. Transparent conductive oxides include metal oxides and metal oxides doped with one or more metals. Examples of such metal oxides and doped metal oxides include indium oxide, indium tin oxide, doped indium oxide, tin oxide, doped tin oxide, zinc oxide, zinc aluminum oxide, doped zinc oxide, ruthenium oxide, doped ruthenium oxide, and the like. The conductive layers are often referred to as "transparent conductive oxide" (TCO) layers, since oxides are often used. Thin metallic coatings that are substantially transparent may also be used. Examples of metals used in such metallic thin film coatings include transition metals such as gold, platinum, silver, aluminum, nickel alloys, etc. A metallic thin film coating of silver, known in the coating industry, is also used. Examples of conductive nitrides include titanium nitride, tantalum nitride, titanium oxynitride, and tantalum oxynitride. The conductive layers 104 and 114 may also be mixed conductors. Such mixed conductors may be fabricated by placing highly conductive ceramic and metal wires or conductive layer patterns on one side of a substrate and coating them with a transparent conductive material such as doped tin oxide or indium tin oxide. Ideally, the wires are thin enough to be invisible to the naked eye (e.g., about 100 μm or less).

[0022] In some embodiments, commercially available substrates, such as glass substrates, are coated with a transparent conductive layer. Such products can be used as both the substrate 102 and the conductive layer 104. Examples of such glasses include conductive coated glasses sold by Pilkington (Toledo, Ohio, USA) under the trade name TEC Glass® and by PPG Industries (Pittsburgh, Pennsylvania, USA) under the trade names SUNGATE® 300 and SUNGATE® 500. TEC Glass® is a glass coated with a conductive layer of fluorinated tin oxide.

[0023] In some embodiments of the present invention, the same conductive layer is used for both conductive layers (i.e., conductive layers 104 and 114). In some embodiments, different conductive materials are used for conductive layers 104 and 114, respectively. For example, in some embodiments, TEC Glass® is used for substrate 102 (float glass) and conductive layer 104 (fluorinated tin oxide), and indium tin oxide is used for conductive layer 114. As mentioned above, in some embodiments using TEC Glass®, a sodium diffusion barrier is provided between glass substrate 102 and TEC conductive layer 104.

[0024] In some embodiments, the composition of the conductive layer, when prepared for manufacturing, must be selected or adjusted based on the composition of the adjacent layer (e.g., electrochromic layer 106 or counter electrode layer 110) that contacts the conductive layer. For example, for a conductive layer made of a metal oxide, the conductivity depends on the number of oxygen vacancies in the conductive layer material, which is affected by the composition of the adjacent layer. Additionally, the criteria for selecting a conductive layer material may include the electrochemical stability of the material and its ability to inhibit oxidation, or more generally, reduction by mobile ionic species.

[0025] The function of the conductive layer is to spread the electrical potential provided by the voltage source 116 across the surface of the electrochromic stack 120 to the interior regions of the stack with very little ohmic potential drop. The electrical potential is transferred to the conductive layer through an electrical connection to the conductive layer. In some embodiments, multiple bus bars are provided to provide electrical connection between the voltage source 116 and the conductive layers 104 and 114, one in contact with the conductive layer 104 and one in contact with the conductive layer 114. The conductive layers 104 and 114 may also be connected to the voltage source 116 using other conventional means.

[0026] In some embodiments, the conductive layers 104 and 114 are between about 5 nm and about 10,000 nm thick. In some embodiments, the conductive layers 104 and 114 are between about 10 nm and about 1,000 nm thick. In other embodiments, the conductive layers 104 and 114 are between about 10 nm and about 500 nm thick. In some embodiments, where TEC Glass® is used for the substrate 102 and the conductive layer 104, the conductive layer is about 400 nm thick. In some embodiments, where indium tin oxide is used for the conductive layer 114, the conductive layer is about 100 nm to 400 nm thick (280 nm in one embodiment). More generally, thicker layers may be formed from the conductive materials listed above, as long as the required electrical properties (e.g., conductivity) and optical properties (e.g., transmittance) are obtained. Generally, the conductive layers 104 and 114 are as thin as possible to increase transparency and reduce cost. In some embodiments, the conductive layers are substantially crystalline. In some embodiments, the conductive layer is a crystalline layer with a high proportion of large equiaxed grains.

[0027] Additionally, the conductive layers 104 and 114 each have a substantially uniform thickness. The conductive layer 104 is desirably a smooth layer (i.e., a layer with a low roughness Ra) so that other layers of the electrochromic stack 120 can be easily applied thereto. In one embodiment, the substantially uniform conductive layer has a variation of about ±10% or less in any of the thickness ranges described above. In another embodiment, the substantially uniform conductive layer has a variation of about ±5% or less in any of the thickness ranges described above. In another embodiment, the substantially uniform conductive layer has a variation of about ±2% or less in any of the thickness ranges described above.

[0028] The sheet resistance (Rs) of the conductive layers is also an important parameter since the areas covered by the layers are relatively large. In some embodiments, the sheet resistance of the conductive layers 104 and 114 is about 5 to 30 ohms / square. In some embodiments, the sheet resistance of the conductive layers 104 and 114 is about 15 ohms / square. In general, it is desirable for the sheet resistance of the two conductive layers to be approximately the same. In one embodiment, the sheet resistance of the two conductive layers is about 10-15 ohms / square.

[0029] Deposited on top of the conductive layer 104 is an electrochromic layer 106. According to embodiments of the invention, the electrochromic layer 106 is inorganic and / or solid, and in typical embodiments, is inorganic and solid. The electrochromic layer may include any one or more of a number of different electrochromic materials, including metal oxides, such as tungsten oxide (WO3), molybdenum oxide (MoO3), niobium oxide (Nb2O5), titanium oxide (TiO2), copper oxide (CuO), iridium oxide (Ir2O3), chromium oxide (Cr2O3), manganese oxide (Mn2O3), vanadium oxide (VO5), nickel oxide (Ni2O3), cobalt oxide (Co2O3), and the like. In some embodiments, the metal oxides are doped with one or more dopants, such as lithium, sodium, potassium, molybdenum, vanadium, titanium, and / or other suitable metals or metal-containing compounds. Mixed oxides (e.g., W-Mo oxide, WV oxide) are also used in certain embodiments. The electrochromic layer 106 including a metal oxide is capable of receiving ions transferred from the counter electrode layer 110.

[0030] In some embodiments, the electrochromic layer 106 is tungsten oxide or doped tungsten oxide. In one embodiment of the present invention, the electrochromic layer is substantially WO x "x" refers to the atomic concentration of oxygen to tungsten in the electrochromic layer and is between about 2.7 and 3.5. It has been suggested that only substoichiometric tungsten oxide produces electrochromism; that is, stoichiometric tungsten oxide, WO3, does not exhibit electrochromism. In a more specific embodiment, the electrochromic layer comprises WO3, where x is less than 3.0 and at least about 2.7. x According to another embodiment, the electrochromic layer is made of WO, where x is between about 2.7 and about 2.9. xThe total number of oxygen atoms, including those bonded to tungsten and those not bonded to tungsten, can be determined by methods such as Rutherford backscattering spectroscopy (RBS). Tungsten oxide layers with x equal to or greater than 3 may also exhibit electrochromism. This is believed to be due to excess unbonded oxygen with substoichiometric tungsten oxide. In another embodiment, the tungsten oxide layer contains stoichiometric or greater amounts of oxygen, with x being between 3.0 and about 3.5.

[0031] According to given embodiments, the tungsten oxide is crystalline, nanocrystalline, or amorphous. According to some embodiments, the tungsten oxide is substantially nanocrystalline, with an average grain size of about 5 nm to 50 nm (or about 5 nm to 20 nm). Such characterization can be seen by transmission electron microscopy (TEM). The tungsten oxide morphology can also be characterized as nanocrystalline using X-ray diffraction (XRD). For example, nanocrystalline electrochromic tungsten oxide can be characterized by XRD with crystallite sizes of about 10 nm to 100 nm (e.g., about 55 nm). Furthermore, nanocrystalline tungsten oxide has limited long-range order, for example, on the order of a few (about 5 to 20) tungsten oxide unit cells.

[0032] The thickness of the electrochromic layer 106 depends on the electrochromic material selected for the electrochromic layer. In some embodiments, the electrochromic layer 106 is about 50 nm to 2,000 nm, or about 200 nm to 700 nm. In some embodiments, the electrochromic layer is about 300 nm to about 500 nm. Additionally, the electrochromic layer 106 is substantially uniform in thickness. In one embodiment, a substantially uniform electrochromic layer has a variation of only about ±10% in any of the thickness ranges described above. In another embodiment, a substantially uniform electrochromic layer has a variation of only about ±5% in any of the thickness ranges described above. In another embodiment, a substantially uniform electrochromic layer has a variation of only about ±3% in any of the thickness ranges described above.

[0033] Generally, in electrochromic materials, the coloration (or any change in optical properties, e.g., absorbance, reflectance, and transmittance) of the electrochromic material is achieved by the reversible incorporation (e.g., intercalation) of ions into the material and the corresponding injection of charge balancing electrons. Typically, some of the ions responsible for such optical changes become irreversibly bound within the electrochromic material. As explained below, some or all of the irreversibly bound ions are used to balance the "hidden charge" within the electrochromic material. Suitable ions for most electrochromic materials include the lithium ion (Li + ) and hydrogen ions (H + ) (i.e., protons). However, other ions may be suitable. Such ions include, for example, the deuterium ion (D + ), sodium ion (Na + ), potassium ion (K + ), calcium ion (Ca ++ ), barium ion (Ba ++ ), strontium ion (Sr ++) and magnesium ions (Mg ++ ) are included. According to various embodiments described herein, lithium ions are used to cause an electrochromic phenomenon. Tungsten oxide (WO 3-y (0 < y ≦ about 0.3), when lithium ions are intercalated, tungsten oxide changes from transparent (bleached state) to blue (colored state).

[0034] Referring back to FIG. 1, in the electrochromic laminate 120, the ion-conducting layer 108 is laminated on the electrochromic layer 106. A counter electrode layer 110 is formed on the ion-conducting layer 108. According to some embodiments, the counter electrode layer 110 is inorganic and / or solid. The counter electrode layer may include one or more of a number of different materials capable of storing ions when the electrochromic device is in the bleached state. For example, when an electrochromic change is initiated by applying an appropriate potential, the counter electrode layer transfers some or all of the ions it holds to the electrochromic layer, changing the electrochromic layer to the colored state. At the same time, in the case of NiWO, the counter electrode layer colors by losing ions.

[0035] In some embodiments, suitable counter electrode materials to complement WO3 include nickel oxide (NiO), nickel tungsten oxide (NiWO), nickel vanadium oxide, nickel chromium oxide, nickel aluminum oxide, nickel manganese oxide, nickel magnesium oxide, chromium oxide (Cr2O3), manganese oxide (MnO2), and Prussian blue. Optically passive counter electrodes include cerium titanium oxide (CeO2-TiO2), cerium zirconium oxide (CeO2-ZrO2), nickel oxide (NiO), nickel tungsten oxide (NiWO), vanadium oxide (VO5), and mixtures of oxides (e.g., mixtures of Ni2O3 and WO3). Doped versions of these oxides may also be used. Examples of dopants include tantalum and tungsten. The counter electrode layer 110 includes ions that are used to generate electrochromic phenomena in the electrochromic material when the electrochromic material is in a bleached state. For this reason, when the counter electrode holds a large amount of such ions, it is preferable that the counter electrode has high transmittance and is achromatic.

[0036] In some embodiments, nickel tungsten oxide (NiWO) is used in the counter electrode layer. In certain embodiments, the amount of nickel in the nickel tungsten oxide can be up to about 90% by weight of the nickel tungsten oxide. In specific embodiments, the weight ratio of nickel to tungsten in the nickel tungsten oxide is between about 4:6 and 6:4 (e.g., about 1:1). In one embodiment, NiWO has, on an atomic basis, between about 15% and about 60% Ni, between about 10% and about 40% W, and between about 30% and about 75% O. In another embodiment, NiWO has, on an atomic basis, between about 30% and about 45% Ni, between about 10% and about 25% W, and between about 35% and about 50% O. In one embodiment, NiWO has, on an atomic basis, about 42% Ni, about 14% W, and about 44% O. The counter electrode layer comprises a substantially amorphous nickel tungsten oxide having an atomic ratio between tungsten and nickel of between about 0.15 and 0.35. Depositing a substantially amorphous nickel tungsten oxide counter electrode layer comprises producing a nickel tungsten oxide having an atomic ratio between tungsten and nickel of between about 0.15 and 0.35.

[0037] When charge is removed from the nickel tungsten oxide counter electrode 110 (ie, ions are transferred from the counter electrode 110 to the electrochromic layer 106), the counter electrode layer changes from a transparent state to a brown state.

[0038] The counter electrode may be crystalline, nanocrystalline, or amorphous. In some embodiments where the counter electrode layer is nickel tungsten oxide, the counter electrode material is amorphous or substantially amorphous. A substantially amorphous nickel tungsten oxide counter electrode has been found to perform better under certain conditions than a crystalline counter electrode. The amorphous state of nickel tungsten oxide may be achieved by applying certain process conditions, as described below. Without being limited to any theory or mechanism, it is believed that the amorphous nickel tungsten oxide is achieved by providing a relatively high atomic energy in the sputtering process. The high atomic energy in the sputtering process can be achieved, for example, by using a high target power, a low chamber pressure (i.e., a high vacuum), and a close source-to-substrate distance. The films produced under the above process conditions are denser and have better stability when exposed to UV / heat.

[0039] In some embodiments, the counter electrode has a thickness between about 50 nm and about 650 nm. In some embodiments, the counter electrode has a thickness between about 100 nm and about 400 nm, preferably in the range of about 200 nm to 300 nm. Additionally, the counter electrode layer 110 has a substantially uniform thickness. In one embodiment, a substantially uniform counter electrode layer has a variation of no more than about ±10% within any of the thickness ranges described above. In another embodiment, a substantially uniform counter electrode layer has a variation of no more than about ±5% within any of the thickness ranges described above. In another embodiment, a substantially uniform counter electrode layer has a variation of no more than about ±3% within any of the thickness ranges described above.

[0040] The amount of ions held by the counter electrode layer in the bleached state (and correspondingly held by the electrochromic layer in the colored state) capable of causing an electrochromic change varies depending on the composition of the layers, as well as the thickness and method of manufacture of the layers. Both the electrochromic and counter electrode layers are capable of holding an effective charge (as lithium ions and electrons) of about tens of millicoulombs per square centimeter of layer surface area. The charge capacity of an electrochromic film is the amount of charge that can be reversibly injected and extracted per unit area and thickness of the film by applying an external voltage or potential. In one embodiment, the WO3 layer has a charge capacity of about 30 to about 150 mC / cm. 2 / micron. In another embodiment, the WO3 layer has a charge capacity of about 50 to about 100 mC / cm 2 / micron. In one embodiment, the NiWO layer has a charge capacity of about 75 to about 200 mC / cm 2 / micron. In another embodiment, the NiWO layer has a charge capacity of between about 100 and about 150 mC / cm 2 / micron.

[0041] Between the electrochromic layer 106 and the counter electrode layer 110, an ion conducting layer 108 is formed. The ion conducting layer 108 acts as a medium for transporting ions (in the manner of an electrolyte) when the electrochromic device changes between a bleached state and a colored state. The ion conducting layer 108 preferably has high ionic conductivity for the electrochromic layer and the counter electrode layer, but low enough electronic conductivity that electron transfer during normal operation is negligible. A thin ion conducting layer with high ionic conductivity can conduct ions quickly, thereby enabling fast switching in high performance electrochromic devices. In certain embodiments, the ion conducting layer 108 is inorganic and / or solid. When produced with materials and methods that result in relatively few defects, the ion conducting layer can be made very thin to achieve high performance devices. In various examples, the ion conducting material has an ionic conductivity of about 108 siemens / cm or ohms -1 cm -1 and about 10 9 siemens / cm or ohms -1 cm -1 The electronic resistance is about 10 11 In ohm-cm.

[0042] Examples of suitable ion conducting layers include silicates, silicon oxides, tungsten oxides, tantalum oxides, niobium oxides, and borates. Silicon oxides include silicon aluminum oxides. These materials may be doped with various dopants, such as lithium. Silicon oxides doped with lithium include lithium silicon aluminum oxides. In some embodiments, the ion conducting layer has a silicate-based structure. In other embodiments, suitable ion conductors, particularly configured to transport lithium ions, include, but are not limited to, lithium silicate, lithium aluminum silicate, lithium aluminum borate, lithium aluminum fluoride, lithium borate, lithium nitride, lithium zirconium silicate, lithium niobate, lithium borosilicate, lithium phosphosilicate, and such lithium-based ceramic materials, silica, or silicon oxides, including lithium silicon oxides. However, the ion conducting layer 108 may be any material that can be fabricated with minimal defects and that allows the passage of ions while significantly inhibiting the passage of electrons from the counter electrode layer 110 to the electrochromic layer 106.

[0043] According to certain embodiments, the ion conductor layer is crystalline, nanocrystalline, or amorphous. The ion conductor layer is generally amorphous. In another embodiment, the ion conductor layer is nanocrystalline. In yet another embodiment, the ion conductor layer is crystalline.

[0044] In some embodiments, the ion conductor layer 108 is silicon aluminum oxide (SiAlO). In a specific embodiment, the silicon / aluminum target used to fabricate the ion conductor layer by sputtering has an aluminum content between about 6 percent and about 20 percent atomic concentration, which determines the silicon to aluminum ratio in the ion conductor layer. In some embodiments, the ion conductor layer 108 made of silicon aluminum oxide is amorphous.

[0045] The thickness of the ion conductor layer 108 may vary depending on the material. In some embodiments, the ion conductor layer 108 has a thickness between about 5 nm and 100 nm, preferably between about 10 nm and 60 nm. In some embodiments, the ion conductor layer has a thickness between about 15 nm and 40 nm, or between about 25 nm and 30 nm. The ion conductor layer has a substantially uniform thickness. In one embodiment, a substantially uniform ion conductor layer has a variation of about ±10% or less in any of the thickness ranges described above. In another embodiment, a substantially uniform ion conductor layer has a variation of about ±5% or less in any of the thickness ranges described above. In another embodiment, a substantially uniform ion conductor layer has a variation of about ±3% or less in any of the thickness ranges described above.

[0046] Ions transported through an ion-conducting layer between the electrochromic layer and the counter electrode layer cause a color change in the electrochromic layer (i.e., change the electrochromic element from a bleached state to a colored state). The ions vary depending on the materials selected for the electrochromic element stack, but lithium ions (Li + ) and hydrogen ions (H + ) (i.e., protons) is one example. As noted above, other ions may be employed in certain embodiments. An example ion is the deuterium ion (D + ), sodium ion (Na + ), potassium ion (K + ), calcium ion (Ca++ ), barium ion (Ba ++ ), strontium ion (Sr ++ ), and magnesium ions (Mg ++ ) are mentioned.

[0047] As mentioned above, the ion conducting layer 108 should have very few defects. The presence of defects in the ion conducting layer is particularly problematic as it can cause short circuits between the electrochromic layer and the counter electrode layer (discussed in more detail below with reference to FIG. 4). A short circuit occurs when oppositely charged conductive layers are connected, for example when a conductive particle comes into contact with each of the two conductive layers (a "pinhole" is the opposite, a defect that does not cause a short circuit between oppositely charged conductive layers). When a short circuit occurs, electrons rather than ions move between the electrochromic layer and the counter electrode when the electrochromic element is in the colored state, often resulting in a bright spot at the short circuit (i.e., several parts of the window do not switch and remain in an open circuit colored state, which is often much brighter than the colored state). The ion conducting layer is preferably thin as long as it does not cause a short circuit between the electrochromic layer and the counter electrode layer. As discussed above, the ion conductor layer 108 can be made thinner by reducing the number of defects present in the ion conductor layer 108 (or in other components of the electrochromic device). A thinner ion conductor layer allows for faster transport of ions between the electrochromic layer and the counter electrode layer using electrochemical cycling. In general, the defect criteria mentioned herein may apply to any layer (ion conductor or other) that constitutes the stack, or to the entire stack, or to any portion of the stack. Defect criteria are discussed further below.

[0048] The electrochromic device 100 may include one or more additional layers (not shown). For example, one or more passive layers may be included. The electrochromic device 100 may include a passive layer to improve a particular optical property. The electrochromic device 100 may include a passive layer to provide water resistance or abrasion resistance. For example, the conductive layer may be treated with an oxide or nitride layer for anti-reflective or protective purposes. Another passive layer may provide a hermetic seal for the electrochromic device 100.

[0049] 2 is a schematic diagram showing a cross-section of an electrochromic element in a bleached state (or in transition to a bleached state). In certain embodiments, the electrochromic element 200 comprises a tungsten oxide electrochromic layer (EC) 206 and a nickel-tungsten oxide counter electrode layer (CE) 210. The tungsten oxide electrochromic layer 206 may be nanocrystalline or near-nanocrystalline in morphology. In some embodiments, the nickel-tungsten oxide counter electrode layer 210 is amorphous or near-amorphous in morphology. In some embodiments, the nickel-tungsten oxide has a weight percent ratio of tungsten to nickel of about 0.40 to 0.60.

[0050] Electrochromic device 200 also includes substrate 202, conductive layer (CL) 204, ion-conducting layer (IC) 208, and conductive layer (CL) 214. In some embodiments, substrate 202 and conductive layer 204 comprise TEC-Glass®. As noted above, electrochromic devices described herein are often useful as architectural glass, such as that depicted in FIG. 2. Thus, in some embodiments, substrate 202 has dimensions that classify it as architectural glass. In some embodiments, conductive layer 214 is indium tin oxide (ITO). In some embodiments, ion-conducting layer 208 is silicon aluminum oxide.

[0051] A voltage source 216 is connected by suitable means (e.g., a bus bar) to the conductive layers 204 and 214 to apply a potential to the electrochromic stack 220. In some embodiments, the voltage source applies a potential of about 2 volts to transition the element from one optical state to another. The polarity of the potential shown in Figure 2 is determined such that ions (lithium ions in this example) are primarily present in the nickel-tungsten oxide counter electrode layer 210.

[0052] In embodiments employing tungsten oxide as the electrochromic layer and nickel-tungsten oxide as the counter electrode layer, the ratio of the thickness of the electrochromic layer to the thickness of the counter electrode layer may be about 1.7:1 to 2.3:1 (e.g., about 2:1). In some embodiments, the tungsten oxide electrochromic layer is about 200 nm to 700 nm thick. In other embodiments, the tungsten oxide electrochromic layer is about 400 nm to 500 nm thick. In some embodiments, the nickel-tungsten oxide counter electrode layer is about 100 nm to 350 nm thick. In other embodiments, the nickel-tungsten oxide counter electrode layer is about 200 nm to 250 nm thick. In yet other embodiments, the nickel-tungsten oxide counter electrode layer is about 240 nm thick. In some embodiments, the silicon aluminum oxide ion conductor layer 208 is about 10 nm to 100 nm thick. In another embodiment, the silicon aluminum oxide ion conducting layer has a thickness of about 20 nm to 50 nm.

[0053] As mentioned above, the electrochromic material may include blind charges. The blind charges in the electrochromic material are charges present in the material at the time of manufacture (e.g., negative charges in the case of tungsten oxide) that are compensated for by ions or other charge carriers of the opposite polarity. For example, in the case of tungsten oxide, the magnitude of the blind charges depends on the excess oxygen concentration during sputtering of the tungsten oxide. Functionally, the blind charges must be compensated for before the ions used to change the electrochromic material can substantially change the optical properties of the electrochromic material. Without pre-compensation for the blind charges, the ions provided to the electrochromic material will be irreversibly incorporated into the electrochromic material and will not be able to affect the optical state of the electrochromic material. For this reason, electrochromic elements are typically provided with a sufficient amount of ions to compensate for the blind charges and to provide ions that can reversibly switch the electrochromic material between two optical states. Examples of ions include lithium ions or protons. In many known electrochromic devices, charge is lost in the first electrochemical cycle to compensate for the blind charge.

[0054] In some embodiments, the electrochromic stack 220 includes a sufficient amount of lithium to compensate for the blind charges present in the electrochromic layer 206, with an additional amount (by mass) of about 1.5 to 2.5 times that amount being used to compensate for the blind charges present in the stack (e.g., initially in the counter electrode layer 210). That is, there is about 1.5 to 2.5 times the amount of lithium required to compensate for the blind charges provided to effect reversible cycling between the electrochromic layer 206 and the counter electrode layer 210 of the electrochromic stack 220. In some embodiments, the electrochromic stack 220 includes a sufficient amount of lithium to compensate for the blind charges present in the electrochromic layer 206, with about twice that amount (by mass) being provided in the counter electrode layer 210 or another component in the stack.

[0055] FIG. 3 is a schematic diagram showing a cross section of the electrochromic element 200 shown in FIG. 2 in a colored state (or transitioning to a colored state). In FIG. 3, the polarity of the voltage source 216 is reversed and the electrochromic layer transitions to a colored state as a more negative potential is applied to receive additional lithium ions. As shown, the lithium ions are transported through the ion conducting layer 208 to the tungsten oxide electrochromic layer 206. The tungsten oxide electrochromic layer 206 illustrates a colored state. The nickel-tungsten oxide counter electrode 210 also illustrates a colored state. As explained, the nickel-tungsten oxide becomes increasingly opaque as it loses lithium ions (as lithium ion deintercalation progresses). In this example, the transitions of both layers 206 and 210 to the colored state have a synergistic effect that has an additive effect on reducing the amount of light transmitted through the stack and the substrate.

[0056] According to certain embodiments, electrochromic devices of the type described above are very reliable, often much more reliable than corresponding devices according to the prior art. Reliability can be characterized by a variety of metrics, some of which are described in ASTM E2141-06 (Standard Test Method for Evaluating the Durability of Absorbing Electrochromic Coatings on Sealed Insulating Glazing). To give a few specific examples, devices of the type described above can be characterized by a T vis and T in colored state vis The electrochromic elements of the present invention can be switched between two distinct optical states (e.g., bleached and colored states) up to 50,000 times while maintaining a ratio of the photopic transmission ratio (also called the photopic transmission ratio (PTR)) to the photopic transmission ratio (PTR) of greater than 4. This long life allows electrochromic elements of the above-described type to be used appropriately in applications where the electrochromic elements are expected to be installed for decades. Furthermore, electrochromic elements according to embodiments of the present invention can be switched between the bleached and unbleached states without losing transmission in the bleached state and without degrading the color or other properties in the unbleached state. In some cases, the high reliability of electrochromic elements according to embodiments described herein is due in part to a design in which the thickness of the electrochromic layer and / or the counter electrode layer of the stack does not change significantly (e.g., about 4% or less) during electrochemical cycling of the electrochromic element compared to its as-deposited, post-lithiation thickness.

[0057] As noted above, many electrochromic devices described herein have a reduced number of defects, i.e., significantly fewer than corresponding prior art devices. The term "defect" as used herein means a defective spot or area of ​​an electrochromic device. A defect may be caused by an electrical short or a pinhole. A defect may also be characterized as being visible or invisible. Generally, defects found in an electrochromic device do not change the optical state (e.g., color) when a voltage potential sufficient to color or change the optical state of a non-defective area of ​​the electrochromic device is applied. Defects often manifest as visually perceptible defects in an electrochromic window or other device. Such defects are referred to herein as "visible" defects. Other types of defects are so small that they are not visually noticeable to a user during normal use (e.g., defects that do not result in a noticeable bright spot when the electrochromic device is colored during daylight). A short is a localized conductive path that forms in an ion-conducting layer (e.g., a conductive path between two TCO layers). Pinholes are areas where one or more layers of an electrochromic element are missing or damaged and do not exhibit electrochromism. Pinholes are not electrical shorts. Three types of defects are of primary concern: (1) visible pinholes, (2) visible shorts, and (3) invisible shorts. Visible shorts are usually, but not necessarily, areas with defect dimensions of at least about 3 micrometers, e.g., about 1 cm in diameter. In visible shorts, the electrochromic effect is visibly smaller. Such areas can be significantly reduced by isolating the defects that create visible shorts so that visible shorts appear similar to visible pinholes to the naked eye. Visible pinholes are defect dimensions of at least about 100 micrometers.

[0058] Electrical shorts can be formed by conductive particles in the ion-conducting layer, thus forming an electronic path between the counter electrode layer and the electrochromic layer or the associated TCO. Defects can also be caused by particles on the substrate (on which the electrochromic stack is fabricated) that can cause delamination (sometimes called "pop-off") or prevent the layers from adhering to the substrate. Both types of defects are discussed below with reference to Figures 4 and 5A-5C. Defects such as delamination or pop-off can cause shorts if they occur before the TCO or associated EC or CE are deposited. In such cases, the subsequently deposited TCO or EC / CE layer is in direct contact with the underlying TCO or CE / EC layer, forming a direct conductive path. Some examples of defect causes are listed in Table 1 below. Table 1 below is presented to provide examples of mechanisms that can cause different types of visible and non-visible defects. Other factors can also affect how defects in the stack affect the EC window. [Table 1]

[0059] Electrical shorts, even if invisible, can cause leakage currents in the ion conducting layer, which can cause a potential drop in the vicinity of the short. If the potential drop is large enough, it can inhibit electrochromic change in the electrochromic element in the vicinity of the short. In the case of a visible short, the defect will result in a bright central area with a fuzzy boundary such that the element becomes gradually darker with distance from the center of the short (when the element is in the colored state). If multiple electrical shorts (visible or invisible) are concentrated in an area of ​​an electrochromic element, a larger area of ​​the element will be affected and unable to switch because the potential difference between the EC and CE layers in the affected area does not reach the threshold required to transport ions through the ion conducting layer. In certain embodiments described herein, shorts (both visible and invisible) are sufficiently controlled that no leakage current effects are observed anywhere in the element. It should also be understood that leakage currents can occur due to causes other than short-type defects. Such other causes include widespread leakage in the ion conductor layer, edge defects such as roll-off defects as described herein, and line defects, but it is emphasized here that leakage occurs only due to point-like electrical shorts in the ion conductor layer in the interior region of the electrochromic device.

[0060] FIG. 4 is a schematic diagram of a cross-section of an electrochromic device 400 illustrating how a particle in an ion-conducting layer creates a localized defect in the electrochromic device. Electrochromic device 400 has the same components as electrochromic device 200 illustrated in FIG. 2. However, electrochromic device 400 has an ion-conducting layer 208 that is defective due to a conductive particle 402 or other artifact. The conductive particle 402 creates a short circuit between electrochromic layer 206 and counter electrode layer 210. This short circuit prevents ions from flowing between electrochromic layer 206 and counter electrode layer 210, but allows electrons to pass locally between the layers, forming a transparent region 404 in electrochromic layer 206 and a transparent region 406 in counter electrode layer 210, while the remainder of layers 210 and 206 are colored. That is, when electrochromic element 400 is in a colored state, conductive particles 402 prevent regions 404 and 406 of the electrochromic element from becoming colored. The defective regions are sometimes called "constellations" because they appear as a series of bright spots (stars) against a dark background (where the rest of the element is colored). Humans naturally draw attention to constellations and often find them distracting or obtrusive.

[0061] FIG. 5A is a schematic diagram showing a cross section of an electrochromic element 500, showing a particle 502 or other debris on the conductive layer 204 prior to deposition of the remainder of the electrochromic stack. The electrochromic element 500 includes the same components as the electrochromic element 200. The particle 502 causes the layers that make up the electrochromic stack 220 to bulge in the area where the particle 502 is located. This is because the conformal layers 206-210 are deposited in sequence above the particle 502 as shown (layer 214 has not yet been deposited in this example). Without wishing to be limited to a particular theory, it is believed that stacking above such particles, given the relatively thin nature of the layers, may create stress in the bulged area. More specifically, defects may be found around the perimeter of the bulged area of ​​each layer, such as cracks or voids in the lattice arrangement or even at a level visible to the naked eye. One effect of such defects may be, for example, an electrical short between electrochromic layer 206 and counter electrode layer 210, or a loss of ionic conductivity in layer 208. Such defects are not shown in FIG. 5A.

[0062] Referring to FIG. 5B, another defect effect that may be caused by particle 502 is illustrated as a "pop-off." In this example, prior to deposition of conductive layer 214, the area of ​​particle 502 above conductive layer 204 breaks away, along with portions of electrochromic layer 206, ion conductor layer 208, and counter electrode layer 210. The "pop-off" is portion 504, which includes particle 502 and portions of electrochromic layer 206, ion conductor layer 208, and counter electrode layer 210. This results in an exposed area of ​​conductive layer 204. Referring to FIG. 5C, when conductive layer 214 is deposited after pop-off, an electrical short occurs where conductive layer 214 contacts conductive layer 204. Such an electrical short causes a clear area to remain in electrochromic element 500 even when the element is in a colored state. This appears similar to the short-circuit defect described above with reference to FIG. 4.

[0063] Pop-off defects caused by particles or debris on the substrates 202 or 204 (see above), the ion conductor layer 208, and the counter electrode layer 210 can result in pinhole defects when the electrochromic element is in the colored state, and particles 502, if large enough, can be visible when the electrochromic element 500 is in the bleached state if they do not cause pop-off.

[0064] Electrochromic elements according to embodiments of the present invention are also scalable to substrates smaller or larger than architectural glass. Electrochromic stacks can be deposited on a wide variety of substrate sizes, up to approximately 12" x 12" or 80" x 120". Electrochromic elements can be fabricated as small as 20" x 20", allowing for the creation of electrochromic architectural glass for many applications.

[0065] Even very small defects that do not result in noticeable bright spots or constellations can cause serious performance problems. For example, small shorts, especially if multiple, can cause relatively large leakage currents in a relatively small area. This can result in large localized potential drops and prevent electrochromic elements from switching in the vicinity of the leakage current. Thus, small defects can limit the dimensional versatility of electrochromic elements and prevent their installation on architectural glass.

[0066] According to one embodiment, the number of visible pinhole defects is about 0.04 or less per square centimeter. According to another embodiment, the number of visible pinhole defects is about 0.02 or less per square centimeter, and according to a more specific embodiment, the number of visible pinhole defects is about 0.01 or less per square centimeter. Visible short-circuit type defects are typically processed separately after fabrication to leave only short-circuit related pinholes as visible defects. According to one embodiment, the number of visible short-circuit related pinhole defects is about 0.005 or less per square centimeter. According to another embodiment, the number of visible short-circuit related pinhole defects is about 0.003 or less per square centimeter, and according to a more specific embodiment, the number of visible short-circuit related pinhole defects is about 0.001 or less per square centimeter. According to one embodiment, the total number of short-circuit related pinholes, pinholes and visible defects formed by isolating the visible short-circuit related defects is less than about 0.1 per square centimeter. In another embodiment, it is less than about 0.08 per square centimeter. In yet another embodiment, there are fewer than about 0.045 defects per square centimeter (resulting in fewer than about 450 defects per square meter of window).

[0067] In some embodiments, multiple invisible electrical short defects have a current density of approximately 5 μA / cm for a bias of ±2 V. 2These values ​​apply across the entire surface of the electrochromic element (i.e., the element has no areas (including on the element) with a defect density greater than the stated values).

[0068] In some embodiments, the electrochromic element is free of visible defects having a diameter (the largest lateral dimension of the defect) of more than about 1.6 mm. In other embodiments, the electrochromic element is free of visible defects having a diameter of more than about 0.5 mm. In other embodiments, the electrochromic element is free of visible defects having a diameter of more than about 100 μm.

[0069] In some embodiments, the electrochromic glass is incorporated into an insulating glass unit (IGU). An IGU is a unit made up of multiple pieces of glass that are combined together to maximize the insulation of the gas contained within the space formed by the unit while still providing clear visibility through the unit. An insulating glass unit incorporating electrochromic glass is similar to currently known insulating glass units, except that it has a wire that connects the electrochromic glass to a voltage source. The higher temperatures encountered with electrochromic insulating glass (due to the electrochromic glass absorbing radiant energy) may require more robust sealing materials than those used in conventional insulating glass units. Examples include stainless steel spacer bars, high temperature polyisobutylene (PIB), new secondary sealing materials, and foil coated PIB tape for spacer bar seams.

[0070] <Manufacturing method of electrochromic windows> Deposition of electrochromic laminates As described in the Summary section above, one aspect of the present invention is a method for fabricating an electrochromic window. Broadly, the method includes sequentially depositing (i) an electrochromic layer, (ii) an ion conductor layer, and (iii) a counter electrode layer on a substrate to form a stack in which the electrochromic layer and the counter electrode layer are separated from each other by the ion conductor layer. The sequential deposition process utilizes a single total composite film system with a controlled ambient environment in which pressure, temperature, and / or gas composition are controlled independently of the external environment outside the total composite film system. The substrate is not removed from the total composite film system at any time during the sequential deposition of the electrochromic layer, the ion conductor layer, and the counter electrode layer. (An example of a total composite film system having a controlled ambient environment is described in more detail below with reference to Figures 8A-8E.) The gas composition may be characterized by the partial pressures of various components in the controlled ambient environment. The controlled ambient environment may be characterized by particle count or particle density. According to a particular embodiment, the controlled ambient environment is 3 Contains less than 350 particles (0.1 micrometers or greater in size) per unit area. In certain embodiments, the controlled ambient environment meets the requirements of a Class 100 cleanroom (US FED STD 209E). In certain embodiments, the controlled ambient environment meets the requirements of a Class 10 cleanroom (US FED STD 209E). The substrate may be moved into and out of the controlled ambient environment in a cleanroom that meets Class 100 or Class 10 requirements.

[0071] This method of manufacture is typically, but not necessarily, incorporated into a multi-step process for manufacturing electrochromic windows utilizing architectural glass as a substrate. For convenience, the following description describes the method and its various embodiments in the context of a multi-step process for manufacturing electrochromic windows, but the method of manufacture of the present invention is not limited thereto. Electrochromic mirrors and other devices may be manufactured using some or all of the processes and methods described herein.

[0072] FIG. 6A is a cross-sectional view of an electrochromic window device 600 according to a multi-step process as described with reference to FIG. 7A. FIG. 7A is a flow chart illustrating a method 700 for manufacturing an electrochromic window incorporating an electrochromic element 600. FIG. 6B is a top view of the element 600, showing the location of the trenches cut into the element. For this reason, FIGS. 6A-6B and 7A are described together. In the following description, an electrochromic window with element 600 as one aspect is described, and a method 700 for manufacturing an electrochromic window with element 600 as another aspect is described. In the following description, reference is also made to FIGS. 7B-7E. FIGS. 7B-7D illustrate specific methods for manufacturing an electrochromic stack that is part of element 600. FIG. 7E is a flow chart illustrating, for example, a conditioning process that may be used to manufacture element 600.

[0073] 6A shows an embodiment of an electrochromic device 600 manufactured using a substrate made of glass 605, which is optionally coated with a diffusion barrier 610 and over which a first transparent conductive oxide (TCO) 615 is coated. The glass 605 is optionally coated with a diffusion barrier 610 and over which a first transparent conductive oxide (TCO) 615 is coated. The substrate used in the method 700 is, for example, float glass provided with a sodium diffusion barrier layer and an anti-reflection layer, followed by a transparent conductive layer, for example a transparent conductive oxide 615. As mentioned above, suitable substrates for the device according to the invention include glasses sold by Pilkington (Toledo, Ohio, USA) under the trade name TEC Glass® and by PPG Industries (Pittsburgh, Pennsylvania, USA) under the trade names SUNGATE® 300 and SUNGATE® 500. The first TCO layer 615 is one of two conductive layers used to form an electrode of the electrochromic device 600 fabricated on the substrate.

[0074] The method 700 begins with a cleaning process 705, which cleans the substrate to prepare it for further processing. As mentioned above, it is important to remove contaminants from the substrate, as they can cause defects in the devices fabricated on the substrate. One critical defect is a particle or other contaminant that can create a conductive path through the IC layers, shorting the device and causing a localized visually perceptible defect in the electrochromic window. An example of a cleaning process and equipment suitable for the manufacturing method of the present invention is Lisec® (a trade name for glass cleaning equipment and processes from LISEC Maschinenbau Gmbh, Seitenstetten, Austria).

[0075] Substrate cleaning may include mechanical scrubbing and ultrasonic cleaning to remove unwanted particles, which, as discussed above, can cause unsightly scratches and localized shorts in the devices.

[0076] Once the substrate is cleaned, a first laser cutting process 710 is performed to cut a line into a first TCO layer on the substrate. In one embodiment, the resulting trench penetrates both the TCO and the diffusion barrier layers (although it may not penetrate substantially through the diffusion barrier layer). FIG. 6A shows a trench 620 formed by this first laser cutting process. The trench is cut into the substrate along the entire length of one side of the substrate to isolate a portion of the TCO near one of the substrate edges that will eventually come into contact with a first bus bar 640. The first bus bar 640 is used to provide current to a second TCO layer 630 that is deposited on top of an electrochromic (EC) stack 625 (which includes an electrochromic layer, an ion conductor layer, and a counter electrode layer, as described above). FIG. 6B shows the location of the trench 620 in a schematic (not to scale) manner. In the illustrated embodiment, the unseparated (major) portion of the first TCO layer above the diffusion barrier will eventually come into contact with the second bus bar 645. The separation trench 620 may be necessary in certain embodiments to press the first bus bar through the layers of the stack of the device after the method of attaching the first bus bar to the device has been laid down (both the separated portion of the first TCO layer and the major portion of the first TCO layer). Those skilled in the art will recognize that other configurations may be used to provide current to the electrodes, which in this example are TCO layers, in the electrochromic device. The TCO area separated by the first laser cutting process is typically an area along one of the edges of the substrate, an area that will eventually be hidden when the bus bar is incorporated into the insulating glass (IGU) and / or window frame, frame, or curtain wall. The laser utilized in the first laser cutting process is typically, but not necessarily, a pulsed laser, for example a diode-pumped solid-state laser. For example, the laser scoring process can be carried out using a suitable laser manufactured by IPG Photonics (Oxford, Massachusetts, USA) or Ekspla (Vilnius, Lithuania).

[0077] The laser forms a trench by engraving from one end of the substrate to the other end along one edge, separating a portion of the first TCO layer. The depth and width dimensions of the trench 620 resulting from the first laser cutting process 710 should be sufficient to separate the first TCO layer from the bulk TCO when the device is subsequently deposited. The depth and width of the trench should be sufficient to prevent remaining particles from shorting through the trench. In one embodiment, the trench is about 300 nm to 500 nm deep and about 20 μm to 50 μm wide. In another embodiment, the trench is about 350 nm to 450 nm deep and about 30 μm to 45 μm wide. In another embodiment, the trench is about 400 nm deep and about 40 μm wide.

[0078] After the first laser cutting process 710, the substrate is cleaned again (operation 715), typically, but not necessarily, using the cleaning methods described above. This second cleaning process is performed to remove debris generated by the first laser cutting process. Once cleaning operation 715 is completed, the substrate is ready for deposition of the EC stack 625, which is shown as process 720 in flow chart 700. As described above, the method includes sequentially depositing (i) an EC layer, (ii) an IC layer, and (iii) a CE layer on the substrate using a single total composite film system with a controlled ambient environment to form a stack in which the IC layer separates the EC and CE layers from each other. The controlled ambient environment has pressure and / or gas composition controlled independently of the external environment outside the total composite film system, and the substrate is not removed from the total composite film system at any time during the sequential deposition of the EC, IC, and CE layers. In one embodiment, each of the layers deposited in sequence is deposited by physical vapor deposition. In general, the layers of the electrochromic device may be deposited using a variety of techniques, including physical vapor deposition, chemical vapor deposition, plasma enhanced chemical vapor deposition, and atomic layer deposition, to name a few. The term "physical vapor deposition" as used herein is intended to include all techniques known in the art as PVD, including sputtering, evaporation, ablation, and the like. FIG. 7B illustrates one embodiment of process 720. First, an EC layer is deposited on a substrate in process 722, an IC layer is deposited in process 724, and a CE layer is deposited in process 726. In another embodiment of the invention, the deposition order is reversed, i.e., the CE layer is deposited first, followed by the IC layer, and finally the EC layer. In one embodiment, the electrochromic layer, the ion conductor layer, and the counter electrode layer are each solid-phase layers. According to another embodiment, each of the electrochromic layer, the ion conductor layer, and the counter electrode layer comprises only inorganic materials.

[0079] Although certain embodiments are described with respect to a counter electrode layer, an ion conducting layer, and an electrochromic layer, it is understood that any one or more of these layers may be comprised of one or more sublayers, each of which may have different compositions, dimensions, morphologies, charge densities, optical properties, etc. Any one or more of the layers of the device may have a graded composition or morphology, i.e., the composition or morphology may vary over at least a portion of the thickness of the layer. In one example, the dopant or charge carrier concentration varies within a given layer, at least during the fabrication of the layer. In another example, the layer morphology varies from crystalline to amorphous. The composition or morphology of such a graded composition may be selected to affect the functional properties of the device. Additional layers may be added to the stack. In one example, a heat spreading layer is provided between one or both of the TCO layers and the EC stack.

[0080] As also described above, electrochromic devices of the present invention utilize the transfer of ions through an ion conducting layer between the electrochromic layer and the counter electrode layer. In some embodiments, these ions (or their neutral precursors) are introduced into the stack as one or more layers (described in more detail below with reference to FIGS. 7C and 7D) and ultimately intercalate into the stack. In some embodiments, these ions are introduced into the stack simultaneously with one or more of the electrochromic layer, the ion conducting layer, and the counter electrode layer. In one embodiment, when lithium ions are used, for example, the lithium is sputtered with the material used to form one or more of the layers of the stack or as part of the lithium-containing material (e.g., using a method using lithium nickel tungsten oxide). In one embodiment, the IC layer is deposited by sputtering a lithium silicon aluminum oxide target. In another embodiment, the lithium is sputtered with the silicon aluminum to form the desired film.

[0081] Referring again to process 722 shown in FIG. 7B, in one embodiment, depositing the electrochromic layer comprises depositing a WO x In this embodiment, the method includes depositing a WO x is generally nanocrystalline in morphology. In some embodiments, the electrochromic layer is deposited to a thickness between about 200 nm and 700 nm. In one embodiment, depositing the electrochromic layer includes sputtering tungsten using a tungsten-containing target. In one such embodiment, a metallic tungsten target (or a metallic tungsten alloy target) is used. In another embodiment (utilizing a metallic tungsten target), the sputtering gas is an inert gas (e.g., argon or xenon) containing a predetermined amount of oxygen-containing gas (e.g., molecular or atomic oxygen). This is part of a controlled ambient environment located within a deposition chamber or deposition station located within a larger chamber. In one embodiment, the gas composition has an oxygen content of between about 30% and about 100%, in another embodiment, an oxygen content of between about 50% and about 80%, and in yet another embodiment, an oxygen content of between about 65% and about 75%. In one embodiment, the tungsten-containing target has a tungsten content (by weight) between about 80% and 100%, in another embodiment the tungsten content is between about 95% and 100%, and in yet another embodiment the tungsten content is between about 99% and 100%. In one embodiment, the gas composition is about 70% / 30% oxygen / argon, and the target is metallic tungsten with a purity between about 99% and 100%. In another embodiment, a tungsten oxide W(O) ceramic target is sputtered, for example, with argon. The pressure in the deposition station or chamber is between about 1 mTorr and about 75 mTorr in one embodiment, between about 5 mTorr and about 50 mTorr in another embodiment, and between about 10 mTorr and about 20 mTorr in another embodiment. In one embodiment, the substrate temperature during process 722 is between about 100° C. and about 500° C., in another embodiment, between about 100° C. and about 300° C., and in another embodiment, between about 150° C. and about 250° C. The substrate temperature may be measured in situ, for example, by a thermocouple, such as an infrared thermocouple (IR t / c). According to one embodiment, the power density for sputtering the EC target is about 2 Watts / cm 2 (obtained by dividing the applied power by the surface area of ​​the target) is approximately 50 watts / cm 2 and in another embodiment between about 10 Watts / cm 2 and about 20 watts / cm 2 and in yet another embodiment between about 15 Watts / cm 2 and about 20 watts / cm 2 In some embodiments, the power provided to achieve sputtering is direct current (DC) power. In other embodiments, pulsed DC / AC reactive sputtering is used. In one embodiment, when pulsed DC / AC reactive sputtering is used, the frequency is between about 20 kHz and about 400 kHz, in another embodiment, between about 20 kHz and about 50 kHz, in yet another embodiment, between about 40 kHz and about 50 kHz, and in another embodiment, about 40 kHz. Any combination of the above conditions may be used to deposit a high quality tungsten oxide electrochromic layer.

[0082] In one embodiment, multiple targets are utilized to normalize the tungsten deposition rate to avoid the need for inappropriately high power (or other inappropriate adjustments to obtain the desired process conditions) to increase the deposition rate. The distance between the target and the substrate can also be important. In one embodiment, the distance between the target (cathode or source) and the substrate surface is between about 35 mm and about 150 mm, in another embodiment, between about 45 mm and about 130 mm, and in another embodiment, between about 70 mm and about 100 mm.

[0083] Although the deposition of the EC layer is described in connection with sputtering using a target, it should be understood that in some embodiments other deposition methods are used, such as chemical vapor deposition, atomic layer deposition, etc. Each of these methods, like PVD, utilizes its own source material, as known to those skilled in the art.

[0084] Referring again to FIG. 7B, once the EC layer is deposited, the IC layer is deposited in operation 724. In one embodiment, depositing the ion conductor layer includes depositing a material selected from the group consisting of tungsten oxide, tantalum oxide, niobium oxide, and silicon aluminum oxide. In another embodiment, depositing the ion conductor layer includes sputtering a target having an aluminum content of between about 2% and 20% by weight (balance silicon) in an oxygen-containing environment to produce a silicon aluminum oxide layer. In a more specific embodiment, the target has an aluminum to silicon content of between about 5% and about 10%, and in another embodiment, an aluminum to silicon content of between about 7% and about 9%. In one embodiment, the gas composition has an oxygen content of between about 15% and about 70%, in another embodiment, an oxygen content of between about 20% and about 50%, in yet another embodiment, an oxygen content of between about 25% and about 45%, and in another embodiment, an oxygen content of about 35%. According to another embodiment, depositing the ion conductor layer includes depositing the ion conductor layer to a thickness between about 10 nm and 100 nm. In yet another embodiment, depositing the ion conductive layer includes depositing the ion conductive layer to a thickness between about 20 nm and 50 nm. In one embodiment, the power density for sputtering the IC target is about 1 Watt / cm. 2 (obtained by dividing the applied power by the surface area of ​​the target) is approximately 20 watts / cm 2 and in another embodiment between about 5 Watts / cm 2 and about 7 watts / cm 2 and in yet another embodiment between about 6 Watts / cm 2 and about 6.5 watts / cm 2In some embodiments, the power provided to achieve sputtering is direct current (DC) power. In another embodiment, pulsed DC / AC reactive sputtering is utilized. In one embodiment, when pulsed DC / AC reactive sputtering is utilized, the frequency is between about 20 kHz and about 400 kHz, in another embodiment, between about 20 kHz and about 50 kHz, in yet another embodiment, between about 40 kHz and about 50 kHz, and in another embodiment, about 40 kHz. The pressure in the deposition station or deposition chamber is in one embodiment, between about 5 mTorr and about 40 mTorr, in another embodiment, between about 10 mTorr and about 30 mTorr, and in another embodiment, about 20 mTorr. In one embodiment, the substrate temperature during process 724 is between about 20° C. and about 200° C., in some embodiments, between about 20° C. and about 150° C., and in yet another embodiment, between about 25° C. and about 100° C. Any combination of the above conditions may be used to deposit a high quality ion conducting layer.

[0085] Referring again to FIG. 7B, once the IC layers are deposited, the CE layer is deposited in operation 726. In one embodiment, depositing the counter electrode layer includes depositing a layer of nickel tungsten oxide (NiWO), preferably amorphous NiWO. In a specific embodiment, depositing the counter electrode layer includes sputtering a target including about 30% to about 70% tungsten (by weight) in nickel in an oxygen-containing environment to produce a nickel tungsten oxide layer. In another embodiment, the target has a tungsten content of between about 40% and about 60% in nickel, in another embodiment, a tungsten content of between about 45% and about 55% in nickel, and in yet another embodiment, a tungsten content of about 51% in nickel. In one embodiment, the gas composition has an oxygen content between about 30% and about 100%, in another embodiment, an oxygen content between about 80% and about 100%, in yet another embodiment, an oxygen content between about 95% and about 100%, and in another embodiment, an oxygen content of about 100%. In one embodiment, the power density for sputtering the CE target is about 2 Watts / cm. 2 (obtained by dividing the applied power by the surface area of ​​the target) is approximately 50 watts / cm 2 and in another embodiment between about 5 Watts / cm 2 and about 20 watts / cm 2 and in yet another embodiment between about 8 Watts / cm 2 and about 10 watts / cm 2 and in another embodiment between about 8 Watts / cm 2 According to some embodiments, the power provided to effectuate sputtering is direct current (DC) power. In another embodiment, pulsed DC / AC reactive sputtering is used. In one embodiment, when pulsed DC / AC reactive sputtering is used, the frequency is between about 20 kHz and about 400 kHz, in another embodiment, between about 20 kHz and about 50 kHz, in yet another embodiment, between about 40 kHz and about 50 kHz, and in another embodiment, about 40 kHz. The pressure in the deposition station or deposition chamber is in one embodiment, between about 1 mTorr and about 50 mTorr, in another embodiment, between about 20 mTorr and about 40 mTorr, in another embodiment, between about 25 mTorr and about 35 mTorr, and in another embodiment, about 30 mTorr. Nickel tungsten oxide (NiWO) ceramic targets may be sputtered with argon and oxygen, for example. In one embodiment, the NiWO has a Ni content (atomic concentration) between about 15% and about 60%, a W content between about 10% and about 40%, and an O content between about 30% and about 75%. In another embodiment, the NiWO has a Ni content (atomic concentration) between about 30% and about 45%, a W content between about 10% and about 25%, and an O content between about 35% and about 50%. In one embodiment, the NiWO has a Ni content (atomic concentration) of about 42%, a W content of about 14%, and an O content of about 44%. In another embodiment, depositing the counter electrode layer includes depositing the counter electrode layer to a thickness between about 150 nm and about 350 nm. In yet another embodiment, the counter electrode layer is deposited to a thickness between about 200 nm and about 250 nm. Any combination of the above conditions may be used to deposit a high quality NiWO layer.

[0086] In one embodiment, multiple targets are utilized to normalize the deposition rate of the CE layer to avoid the need for inappropriately high power (or other inappropriate adjustments to obtain the desired process conditions) to increase the deposition rate. In one embodiment, the distance between the CE target (cathode or source) and the substrate surface is between about 35 mm and about 150 mm, in another embodiment between about 45 mm and about 130 mm, and in another embodiment between about 70 mm and about 100 mm.

[0087] As shown in FIG. 7B and also in FIG. 6A, the order of deposition process is illustrated as EC layer first, followed by IC layer, and finally CE layer, however, it is understood that in various embodiments, this order can be reversed. In other words, when layers constituting the stack are referred to as being deposited "sequentially," this includes the "forward" order described above as well as the "reverse" order of depositing the CE layer first, the IC layer second, and the EC layer third. Both the forward and reverse orders can produce reliable and high quality electrochromic devices. Additionally, although conditions are described for depositing the various ingredients of the EC, IC, and CE layers described herein, it is understood that these conditions are not limited to depositing the ingredients described. Other ingredients may be deposited under the same or similar conditions. Additionally, in some embodiments, deposition conditions other than sputtering may be used to produce the same or similar deposited materials as described with reference to FIGS. 6A and 6B and 7A-7E.

[0088] The amount of charge that each of the EC and CE layers can safely hold varies depending on the materials used, and the relative thicknesses of each layer may be controlled to suit the capacity. In one embodiment, the electrochromic layer comprises tungsten oxide, the counter electrode comprises tungsten nickel oxide, and the ratio of the thickness of the electrochromic layer to the thickness of the counter electrode layer is between about 1.7:1 and 2.3:1, or between about 1.9:1 and 2.1:1, with a specific example being about 2:1.

[0089] Referring again to FIG. 7B, after depositing the CE layer, the EC stack is completed in operation 720. Operation 720 is described in FIG. 7A as "deposit stack," but should be understood to mean the EC stack and the second TCO layer (also called "ITO" when indium tin oxide is used to form the second TCO). Generally, "stack" herein refers to the EC-IC-CE layer, i.e., the "EC stack." Referring again to FIG. 7B, in one embodiment, process 728 deposits a TCO layer onto the stack. Referring to FIG. 6A, this corresponds to second TCO layer 630 on EC stack 625. Process 720 ends upon completion of process 728. A cap layer is deposited on the EC stack, although this is not required. In some embodiments, the cap layer is SiAlO, similar to the IC layer. In some embodiments, the cap layer is deposited by sputtering under similar conditions to those of the IC layer. The cap layer typically has a thickness of about 30 nm to 100 nm. In one embodiment, the transparent conductive oxide layer is deposited under conditions that result in a sheet resistance between about 10 ohms / sq and 30 ohms / sq. In one embodiment, as described above, the first and second TCO layers have the same sheet resistance to optimize the efficiency of the electrochromic device. Ideally, the morphology of the first TCO layer is smooth so that the layers that make up the deposited stack are more conformal. In one embodiment, the substantially uniform TCO layer has a variation of only about ±10% in each of the thickness ranges described above. In another embodiment, the substantially uniform TCO layer has a variation of only about ±5% in each of the thickness ranges described above. In another embodiment, the substantially uniform TCO layer has a variation of only about ±2% in each of the thickness ranges described above.

[0090] In certain embodiments, the second TCO layer 630 is deposited using some or all of the conditions listed below. The conditions listed may be used to form a thin, low defect indium tin oxide layer by sputtering a tin oxide indium oxide target with, for example, argon sputtering gas with or without oxygen. In one embodiment, the TCO layer has a thickness between about 5 nm and about 10,000 nm, in another embodiment between about 10 nm and about 1,000 nm, and in yet another embodiment between about 10 nm and about 500 nm. In one embodiment, the substrate temperature during operation 728 is between about 20° C. and about 300° C., in another embodiment between about 20° C. and about 250° C., and in another embodiment between about 80° C. and about 225° C. In one embodiment, the TCO layer is deposited by sputtering a target having (by weight) about 80% to about 99% In2O3 and about 1% to about 20% SnO2 with an inert gas, optionally oxygen. In a more specific embodiment, the target has (by weight) about 85% to about 97% In2O3 and about 3% to about 15% SnO2. In another embodiment, the target has (by weight) about 90% In2O3 and about 10% SnO2. In one embodiment, the gas composition has an oxygen content between about 0.1% and about 3%, in another embodiment an oxygen content between about 0.5% and about 2%, in yet another embodiment an oxygen content between about 1% and about 1.5%, and in another embodiment an oxygen content of about 1.2%. In one embodiment, the power density for sputtering the TCO target is about 0.5 Watts / cm 2 (obtained by dividing the applied power by the surface area of ​​the target) is approximately 10 watts / cm 2 and in another embodiment between about 0.5 Watts / cm 2 and about 2 watts / cm 2 and in yet another embodiment between about 0.5 Watts / cm 2 and about 1 watt / cm 2 and in another embodiment between about 0.7 Watts / cm2 In some embodiments, the power provided to achieve sputtering is direct current (DC) power. In another embodiment, pulsed DC / AC reactive sputtering is utilized. When pulsed DC / AC reactive sputtering is utilized, the frequency is between about 20 kHz and about 400 kHz in one embodiment, between about 50 kHz and about 100 kHz in another embodiment, between about 60 kHz and about 90 kHz in yet another embodiment, and about 80 kHz in another embodiment. The pressure in the deposition station or deposition chamber is between about 1 mTorr and about 10 mTorr in one embodiment, between about 2 mTorr and about 5 mTorr in another embodiment, between about 3 mTorr and about 4 mTorr in another embodiment, and about 3.5 mTorr in another embodiment. In one embodiment, the indium tin oxide layer has an In content (atomic concentration) between about 20% and about 40%, an Sn content between about 2.5% and about 12.5%, and an O content between about 50% and about 70%. In another embodiment, the In content is between about 25% and about 35%, an Sn content is between about 5.5% and about 8.5%, and an O content is between about 55% and about 65%. In another embodiment, the In content is about 30%, the Sn content is between about 8%, and the O content is between about 62%. Any combination of the above conditions may be used to deposit a high quality indium tin oxide layer.

[0091] As described above, the EC stack is fabricated in a total synthesis film system, and the substrate is not removed from the total synthesis film system at any time during the fabrication of the stack. In one embodiment, the second TCO layer is also formed using the total synthesis film system, and the substrate is not removed from the total synthesis film system during the deposition of the EC stack and the TCO layer. In one embodiment, both layers are deposited in a total synthesis film system, and the substrate is not removed from the total synthesis film system during the deposition. That is, in one embodiment, the substrate is a glass sheet, and the stack having the EC layer, the IC layer, and the CE layer is sandwiched between the first TCO layer and the second TCO layer and fabricated on the glass. In this case, the glass is not removed from the total synthesis film system during the deposition. In another implementation of the embodiment, the substrate is a glass on which a diffusion barrier is deposited before being introduced into the total synthesis film system. In another embodiment, the substrate is composed of glass and a diffusion barrier, and a stack having an EC layer, an IC layer, and a CE layer is sandwiched between a first TCO layer and a second TCO layer, all of which are deposited on the glass without removing the glass from the total composite coating system during deposition.

[0092] Without wishing to be limited by theory, it is believed that prior art electrochromic devices suffer from defects for a variety of reasons. One of the reasons is that an unacceptable number of particles are introduced into the IC layer during fabrication. No consideration was given to depositing the EC, IC and CE layers in a single total synthesis deposition apparatus in a controlled ambient environment. In one process, the IC layer is deposited in a sol-gel process that must be run separately from the other vacuum integration processes. In such a process, even if the EC and / or CE layers are deposited in a controlled ambient environment to produce high quality layers, the substrate must be removed from the controlled ambient environment to deposit the IC layer. In this case, the substrate typically passes through a load lock (moving from a controlled ambient environment, such as a vacuum, to an external environment) before the IC layer is deposited. Passing through the load lock typically introduces a large number of particles onto the substrate. This introduction of particles immediately prior to deposition of the IC layer greatly increases the likelihood of defects forming in the critical IC layer. The formation of such defects results in bright spots or "constellations" as described above.

[0093] As discussed above, lithium may be provided during formation of the EC, CE and / or IC layers on a substrate, for example by co-sputtering lithium with other materials (e.g., tungsten and oxygen) for a given layer, or in certain embodiments described below, lithium is provided in a separate process and diffused or incorporated into the EC, CE and / or IC layers.

[0094] Direct lithiation of electrochromic laminates In some embodiments, as described above, the intercalation of lithium ions provides the electrochromic stack with the ability to switch optical states. It is understood that the necessary lithium may be introduced into the stack by a variety of means. For example, lithium may be provided to one or more of the layers described above at the same time as the materials for that layer are deposited (e.g., lithium and tungsten oxide are deposited simultaneously during the formation of the EC layer). However, the process shown in FIG. 7B may be interrupted by one or more treatments that provide lithium to the EC, IC and / or CE layers. For example, lithium may be introduced by one or more separate lithiation steps that provide lithium elementally in the substantial absence of deposition of other materials. Such lithiation steps may be performed after deposition of the EC, IC and / or CE layers. Alternatively (or in addition), one or more lithiation steps may be performed between the steps performed to deposit a layer. For example, the counter electrode layer may be formed by first depositing a limited amount of nickel tungsten oxide, followed by direct deposition of lithium, and finally depositing an additional amount of nickel tungsten oxide. Such an approach may have the advantage of providing better isolation between the lithium and the ITO (or other material that constitutes the conductive layer), which may improve adhesion and reduce undesired side reactions. An example of a stack formation process in which a separate lithiation step is performed is shown in FIG. 7C. In some cases, the lithiation step is performed during a pause in the deposition of a given layer to introduce lithium before the deposition of that layer is completed.

[0095] FIG. 7C is a flow chart illustrating process 720a for depositing a stack on a substrate in a manner similar to process 720 shown in FIG. 7A. Process 720a includes process 722 for depositing an EC layer, process 724 for depositing an IC layer, and process 726 for depositing a CE layer, as described with reference to FIG. 7B. Process 720a, however, differs from 720 by the addition of lithiation processes 723 and 727. In one embodiment, the lithium is deposited by physical vapor deposition using a total synthesis film system. Note that the substrate is not removed from the total synthesis film system at any time during the sequential deposition of the electrochromic layer, the ion conductor layer, the counter electrode layer, and the lithium.

[0096] In certain embodiments, lithium is deposited using a high voltage lithium cathode since secondary electron emission during lithium sputtering is not significant. In some embodiments, the power provided to perform the sputtering is direct current (DC) power. In other embodiments, pulsed DC / AC reactive sputtering is used. In one embodiment, pulsed DC / AC reactive sputtering is used at a frequency between about 20 kHz and about 400 kHz, in another embodiment between about 100 kHz and about 300 kHz, in yet another embodiment between about 200 kHz and about 250 kHz, and in another embodiment at about 220 kHz. A lithium target is used. In one embodiment, the target has a Li content between about 80% and 100% (by weight), in another embodiment between about 90% and about 99% Li, and in another embodiment about 99% Li. Lithiation is typically performed in an inert environment (e.g., argon only) since the lithium element is very reactive. The power density for sputtering the lithium target is about 1 Watt / cm. 2 (based on the deposition surface area of ​​the substrate) and approximately 10 Watts / cm 2 and in another embodiment between about 2 Watts / cm 2 and about 4 watts / cm 2and in yet another embodiment between about 2.5 Watts / cm 2 and about 3 watts / cm 2 and in another embodiment between about 2.7 Watts / cm 2 In one embodiment, the lithium sputtering is performed at a pressure between about 1 mTorr and about 20 mTorr, in another embodiment between about 5 mTorr and about 15 mTorr, and in another embodiment about 10 mTorr. Any combination of the above conditions may be used to perform a high quality lithiation process deposition.

[0097] In one embodiment, lithium is deposited on both the EC and CE layers as shown in dual lithiation process 720a. After depositing the EC layer in operation 722 as described above, lithium is sputtered onto the EC layer in operation 723. After this, the IC layer is deposited in operation 724, and then the CE layer is deposited in operation 726. After this, lithium is deposited onto the CE layer in operation 727. For example, in one embodiment where the EC layer is made of tungsten oxide and has a thickness approximately twice that of the CE layer of nickel tungsten oxide, the total amount of lithium added to the stack is adjusted to have a ratio of approximately 1:3 to 2:3 between the EC and CE layers. That is, approximately 1 / 3 of the total amount of lithium added to the stack is sputtered into the EC layer and approximately 2 / 3 into the CE layer. In a specific embodiment, the lithium added to the stack is adjusted to have a ratio of approximately 1:2 between the EC and CE layers.

[0098] The illustrated dual lithiation method lithiates both the EC and CE layers. Without wishing to be limited by theory, it is believed that providing lithium to both the EC and CE layers improves performance and yield. The relatively large volume change that may occur at initial equilibrium due to the injection of lithium ions into the (as-fabricated) depletion layer (compared to lithiation on only one side of the IC layer) is avoided. Such volume change, reported to be as much as 6% in initially lithium-free electrochromic tungsten oxide, can lead to cracking and delamination of the layers that make up the stack. This can be improved by producing a stack with the dual lithiation process described herein, resulting in a volume change of less than 6% for the electrochromic layers. In certain embodiments, the volume change is at most about 4%.

[0099] In one embodiment of the dual lithiation process, as described above, the EC layer is treated with sufficient lithium to satisfy the requirement that the EC material irreversibly bind lithium (e.g., to compensate for the "blind charges"). The CE layer (which may also have blind charges) is added with the lithium required for reversible cycling. In certain embodiments, the lithium required to compensate for the blind charges can be titrated by monitoring the optical density of the EC layer as lithium is added, since the EC layer does not substantially change color until sufficient lithium has been added to fully compensate for the blind charges.

[0100] Those skilled in the art will appreciate that because metallic lithium is a pyrophoric material, i.e., highly reactive to moisture and oxygen, the lithiation methods described herein in which lithium may be exposed to oxygen or moisture may be performed in a vacuum atmosphere, an inert atmosphere, or both. The controlled ambient environment utilized in the apparatus and methods of the present invention allows for flexibility in lithium deposition, particularly when multiple lithiation steps are performed. For example, the lithium may be protected from exposure to oxygen or moisture when lithiation is performed in a titration process and / or when lithiation is performed between steps in the build-up of a stack.

[0101] In certain embodiments, the lithiation is carried out at a rate sufficient to prevent the formation of a significant thickness of free lithium on the surface of the EC layer. In one embodiment, in the lithiation of the EC layer, the lithium targets are spaced apart enough to allow time for the lithium to diffuse into the EC layer. Optionally, the substrate (and EC layer) is heated to a temperature between about 100° C. and about 150° C. to improve the diffusion of lithium into the EC layer. The heating process may be performed separately or in combination with the target spacing and substrate translation relative to the target. The substrate may also be shuttled in front of the sputtering lithium target to slow the supply of lithium to the substrate and prevent the accumulation of free metallic lithium on the surface of the stack.

[0102] The lithiation process may also be performed while implementing an isolation protocol. In one example, the isolation protocol is performed using an isolation valve in the total synthesis film system. For example, when the substrate enters the lithiation station, the isolation valve is closed to isolate the substrate from the other stations and to prepare the substrate for lithiation, for example by introducing argon or applying a vacuum. In another embodiment, the isolation is achieved by manipulating the controlled ambient environment. For example, pressure differences are used in the lithiation station of the total synthesis film system to create fluid dynamics in the controlled ambient environment to ensure that the lithium deposition is sufficiently isolated from other processes in the total synthesis film system. In another embodiment, the above conditions are combined. For example, valves are partially closed (or the lithiation station may be configured to minimize the substrate inlet and / or outlet) and one or more fluid dynamics are used to further isolate the lithiation process from adjacent processes. Referring again to FIG. 7C, after the dual lithiation process described in operations 722 to 727, a (second) TCO layer is deposited (in operation 728) as described above.

[0103] FIG. 7D is a flow chart illustrating another process 720b for depositing a stack on a substrate. The process is similar to process 700 of FIG. 7A. Process 720b includes depositing an EC layer (process 722), an IC layer (process 724), and a CE layer (process 726), as described with reference to FIG. 7B. However, process 720b differs from process 720 in that it includes a lithiation process 727. In this embodiment, the stack deposition process adds all the lithium required by supplying lithium to the CE layer, and the lithium is intercalated into the EC layer by diffusing through the IC layer during and / or after the stack fabrication. As described above, unlike the double lithiation process 720a, this method inevitably incurs a large volume change due to supplying all the lithium required by the device to one side of the IC layer, but has the advantage of reducing one lithium supply step.

[0104] <Multi-stage thermochemical adjustment> Referring again to FIG. 7A, once the stack is deposited, the device is subjected to a multi-step thermochemical conditioning (MTC) process (see block 730). The MTC process is typically performed only after all layers of the electrochromic stack are formed. Some embodiments of the MTC process 730 are illustrated in more detail in FIG. 7E. It should be noted that the MTC process can be performed entirely ex-situ, i.e., outside the total synthetic film system used to deposit the stack, without, for example, breaking the vacuum or moving the substrate outside the controlled ambient environment used to fabricate the stack, or at least partially in-situ, i.e., inside the deposition system. In certain embodiments, the first part of the MTC process is performed in-situ and the second part is performed ex-situ. In certain embodiments, some of the MTC process is performed before depositing certain layers, for example, before depositing the second TCO layer.

[0105] Referring to FIG. 7E, in certain embodiments, the device is first heat treated under non-reactive conditions (e.g., inert gas). See block 732. According to specific embodiments, the device is heated at a temperature between about 200° C. and about 350° C. for a period between about 5 minutes and about 30 minutes. According to certain embodiments, treatment 732 is performed at low pressure or low vacuum. Without wishing to be limited by theory, it is believed that heating under inert gas provides lithium to the CE layer as excess lithium migrates from the EC layer to the CE layer (as may be evidenced by the increased transparency of the CE layer during this treatment). The device is then heat treated under reactive conditions. See block 734. According to some embodiments, this treatment includes annealing the device in an oxidizing atmosphere (e.g., an atmosphere of oxygen and inert gas at a pressure of about 10-50 mTorr). According to certain embodiments, the annealing is performed at a higher pressure than the non-reactive heat treatment (732). According to a particular embodiment, the element is heated to a temperature between about 200° C. and about 350° C. for a period of between about 3 minutes and about 20 minutes. Without wishing to be limited by theory, it is believed that the oxidative annealing process improves the conductivity of NiWO by forming a matrix of Li2WO4 (which is highly lithium ion conductive) that encapsulates the individual NiWO particles. NiWO embedded within a highly ionically conductive matrix speeds up the optical change.

[0106] Optionally, after the oxidation annealing, the element is heated in air (ex situ). In one embodiment, the element is heated in process 736 at a temperature between about 150° C. and about 500° C. for a period between about 1 minute and about 60 minutes. In another embodiment, the element is heated at a temperature between about 200° C. and about 400° C. for a period between about 5 minutes and about 30 minutes. It is understood that the MTC process includes two, three, or more separate and distinct processes. Although three processes are described herein, they are only intended to be illustrative of the processes. Also, the process conditions described herein are appropriate for architectural glass, but may need to be modified for other applications. The time for which the element is heated will depend on the size of the element. Once the MTC process is complete, the element is ready for further processing.

[0107] As mentioned above, additional layers may be required to improve optical performance (e.g., anti-reflection), durability (with respect to physical handling), hermeticity, etc. Such addition of one or more layers is intended to be included in embodiments other than those described above.

[0108] <Manufacturing process for completing the element> Referring again to FIG. 7A, a second laser cutting process (block 740) is performed. The laser cutting process 740 is performed along the length of the substrate near the outer edge of the stack, on two sides of the substrate perpendicular to the first laser cutting process. FIG. 6B shows the location of the trench 626 formed by the laser cutting process 740. This cutting process is performed through the first TCO (and diffusion barrier, if present) to the substrate to further separate the separated portions of the first TCO layer (where the first busbar is connected) and to separate the stack coating at the edges (e.g., near the mask) to minimize short circuits due to deposition roll-off of the layers that make up the stack. In one embodiment, the trench is between about 25 μm and 75 μm deep and between about 100 μm and 300 μm wide. In another embodiment, the trench is between about 35 μm and 55 μm deep and between about 150 μm and 250 μm wide. In another embodiment, the trench is about 50 μm deep and about 150 μm wide.

[0109] A third laser cutting process 745 is then performed along the periphery of the stack near the edge of the substrate, opposite and parallel to the first laser cutting process. This third laser cutting process only needs to be deep enough to separate the second TCO layer and the EC stack, but not through the first TCO layer. Referring to FIG. 6A, the laser cutting process 745 forms a trench 635, which separates the uniform and conformal portion of the EC stack and the second TCO from the outermost edge, which exhibits roll-off problems (e.g., as shown in FIG. 6A, where layers 625 and 630 are separated near region 650 by cutting trench 635), resulting in a short between the first and second TCO layers in region 650, near where the second busbar is attached. The trench 635 is also configured to separate the roll-off region of the second TCO from the second busbar. The trench 635 is also shown in FIG. 6B. One skilled in the art will appreciate that the second and third laser cutting processes, although of different depths, may be performed in one process, and thus the laser cutting depth may be varied while continuing across the three sides of the substrate as described above, first along a first side perpendicular to the first laser cutting process to a depth sufficient to penetrate the first TCO (and optionally the diffusion barrier), along an opposite side parallel to the first laser cutting process to a depth sufficient to penetrate to the bottom of the EC stack, and then along a third side perpendicular to the first laser cutting process to the initial depth.

[0110] Referring back to process 700 as shown in FIG. 7A, after the third laser cutting process, the busbars are attached in process 750. Referring to FIG. 6A, a first busbar 640 and a second busbar 645 are attached. The first busbar is often pressed through the second TCO and EC stack to contact the second TCO layer, for example by ultrasonic soldering. This connection method requires a laser cutting process to separate the area of ​​the first TCO where the first busbar contacts. Those skilled in the art will recognize that other means (e.g., patterning methods such as screen printing and lithography) can also be used to connect the first busbar (or a replacement for the older busbar) to the second TCO layer. In one embodiment, the transparent conductive layers of the device are connected by printing a conductive ink using silk screen printing (or another patterning method) followed by thermal curing or sintering of the ink. When using such a method, no separation of a portion of the first TCO layer is performed. Using process 700, an electrochromic element is formed on a glass substrate, with a first bus bar in electrical communication with the second TCO layer 630 and a second bus bar in electrical contact with the first TCO layer 615. In this way, the first and second TCO layers function as electrodes of the EC stack.

[0111] Referring again to FIG. 7A, after the busbars are connected, the electrochromic device is assembled into an insulating glass unit (IGU) in process 755. The IGU is formed by placing a gasket or sealant (e.g., made of polyvinyl butyral (PVB), PIB or other suitable elastomer) along the periphery of the substrate. Typically, but not necessarily, a desiccant is included in the IGU frame or spacer bar during assembly for water absorption. In one embodiment, the sealant is provided around the periphery of the busbars, and the electrical wires to the busbars extend through the sealant. After the sealant is placed, a second glass sheet is placed on the sealant, and the space defined by the substrate, second glass sheet and sealant is filled with an inert gas, typically argon. Once the IGU is complete, process 700 is terminated. The completed IGU is installed, for example, in a window frame, frame or curtain wall, and connected to a controller and power source for operating the electrochromic window.

[0112] In addition to the steps described in connection with the method above, one or more edge removal steps may be added. Edge removal is part of the manufacturing process for incorporating the electrochromic element into, for example, a window. This removes roll-off (as described with reference to FIG. 6A) before the element is incorporated into the window. If unmasked glass is used, any coating that would extend below the IGU frame is removed before incorporation into the IGU (which is undesirable for long term reliability). This edge removal step is included in the method above as an alternative to the embodiment described above.

[0113] <Total synthetic membrane system> As described above, a total synthesis film system may be used to fabricate electrochromic devices on architectural glass, for example. As described above, electrochromic devices are used to fabricate IGUs. IGUs are used to fabricate electrochromic windows. The term "total synthesis film system" refers to an apparatus for fabricating electrochromic devices on optically transparent and translucent substrates. The apparatus includes multiple stations, each station dedicated to one of a particular unit process, such as depositing a particular component (or part of a component) of the electrochromic device, cleaning, etching, and temperature control of the electrochromic device or part thereof. The multiple stations are fully integrated such that the substrate on which the electrochromic device is being fabricated is not exposed to the outside environment as it moves between the stations. The total synthesis film system of the present invention performs processing in a controlled ambient environment provided within the system. The controlled ambient environment includes multiple processing stations. A fully integrated total synthesis film system allows for better control of the interface quality of each layer deposited. Interface quality refers to, among other factors, adhesion between layers and the absence of contaminants in the interface area. The term "controlled ambient environment" refers to a sealed environment or clean room that is separate from an external environment, such as an open air environment. In a controlled ambient environment, the pressure and / or gas composition are controlled independently of the conditions of the external environment. Typically, but not necessarily, a controlled ambient environment has a pressure less than atmospheric pressure, e.g., at least a partial vacuum. The conditions in the controlled ambient environment may be constant during processing or may change over time. For example, a layer of an electrochromic device may be deposited in a vacuum in a controlled ambient environment, and at the end of the deposition process, the controlled ambient environment may be backfilled with a purge gas or reagent gas, the pressure may be increased, e.g., to atmospheric pressure, in preparation for processing at another station, and then evacuated again for the next processing, etc.

[0114] In one embodiment, the system includes a plurality of deposition stations arranged in series and connected to each other such that the substrate can be transported from one station to the next without exposing the substrate to an external environment. The plurality of deposition stations includes a first deposition station having a target for depositing an electrochromic layer, a second deposition station having a target for depositing an ion conducting layer, and a third deposition station having a target for depositing a counter electrode layer. The system further includes a controller having program instructions for transporting the substrate between the plurality of stations. The substrate is transported to sequentially deposit the electrochromic layer, the ion conducting layer, and the counter electrode layer on the substrate to form a stack in which the ion conducting layer separates the electrochromic layer and the counter electrode layer from each other. In one embodiment, the plurality of deposition stations allows the substrate to be transported between the stations without breaking the vacuum. In another embodiment, the plurality of deposition stations are configured to deposit an electrochromic layer, an ion conductor layer, and a counter electrode layer on the architectural glass substrate. In another embodiment, the total deposition system includes a substrate holding and transporting mechanism capable of holding the architectural glass substrate in a vertical orientation at the plurality of deposition stations. In yet another embodiment, the total deposition system includes one or more load locks for transporting the substrate between an external environment and the total deposition system. In another embodiment, the plurality of deposition stations includes at least two stations for depositing a layer selected from the group consisting of an electrochromic layer, an ion conductor layer, and a counter electrode layer.

[0115] In some embodiments, the total synthesis film system includes one or more lithium deposition stations having lithium-containing targets. In one embodiment, the total synthesis film system includes two or more lithium deposition stations. In one embodiment, the total synthesis film system includes one or more isolation valves for isolating each processing station from the other stations during processing. In one embodiment, one or more lithium deposition stations have isolation valves. As used herein, the term "isolation valve" refers to a device for isolating a deposition or other process performed at a station from the processes at other stations of the total synthesis film system. In one example, the isolation valve is a physical (solid) isolation valve that is provided in the total synthesis film system and operates during lithium deposition. The actual physical solid valve may operate to completely or partially isolate (or isolate) the lithium deposition process from other processes or stations in the total synthesis film system. In another embodiment, the isolation valve may be a gas knife or gas shield. For example, a partial pressure of argon or other inert gas may span the area between the lithium deposition station and other stations to prevent ions from flowing into the other stations. In another example, the isolation valve may be a vacuum region between the lithium deposition station and other processing stations, where lithium ions or ions from other stations may enter the vacuum region and be removed, for example, to a waste stream, rather than contaminating adjacent processes. This configuration may be achieved, for example, by creating fluid dynamics in a controlled ambient environment by using different pressures in the lithiation station of the total synthesis membrane system, such that the lithium deposition is sufficiently isolated from other processes in the total synthesis membrane system. Again, the isolation valve is not limited to the lithium deposition station.

[0116] FIG. 8A is a schematic diagram showing a total synthesis film system 800 according to a specific embodiment. In this example, the system 800 includes an input load lock 802 for introducing a substrate into the system and an output load lock 804 for removing the substrate from the system. The load locks allow the substrate to be introduced and removed from the system without disturbing the controlled ambient environment of the system. The total synthesis film system 800 includes a module 806 having a number of deposition stations including an EC layer deposition station, an IC layer deposition station, and a CE layer deposition station. In a broad sense, the total synthesis film system according to the present invention does not need to include a load lock. For example, the module 806 alone can function as a total synthesis film system. For example, the substrate can be introduced into the module 806 to form a controlled ambient environment to process the substrate at various stations in the system. Individual stations within the total composite film system may include heating sections, cooling sections, various sputtering targets and target movement means, RF and / or DC power sources and power delivery mechanisms, etching sections for plasma etching and the like, gas sources, vacuum sources, glow discharge sources, monitors and sensors for process parameters, robots, power sources, and the like.

[0117] FIG. 8B is a perspective view of a portion (or simplified version) of the total composite film system 800, with a more detailed cutaway view of the internal components. In this example, the system 800 is a modular system with an input load lock 802 and an output load lock 804 connected to a deposition module 806. An input port 810 is provided for inputting, for example, architectural glass substrates 825 (with a corresponding output port in the load lock 804). The substrates 825 are supported by a pallet 820, which moves along a track 815. In this example, the pallet 820 is suspended and supported by the track 815, but the pallet 820 may be supported on a track disposed near the bottom of the apparatus 800, or may be supported on a track disposed, for example, midway between the top and bottom of the apparatus 800. The pallet 820 may translate back and forth (as indicated by the double-headed arrow) within the system 800. For example, during lithium deposition, the substrate may be moved back and forth in front of the lithium target 830, making multiple passes to achieve the desired lithiation. The pallet 820 and substrate 825 are oriented generally vertically. A generally vertical orientation may help reduce defects, for example, but not by way of limitation, because particulate matter that may form from the clumping of atoms resulting from sputtering tends to be overcome by gravity and does not deposit on the substrate 825. Additionally, because architectural glass substrates tend to be large, a vertical orientation of the substrate during transport between stations of a total synthesis coating system allows for the coating of thinner glass substrates with less concern for sagging, which occurs with thicker, hotter glass.

[0118] The target 830, which in this example is a cylindrical target, is oriented generally parallel to and in front of the substrate surface on which deposition is to occur (for ease of illustration, other sputtering tools are not shown). During deposition, the substrate 825 translates past the target 830 and / or the target 830 moves in front of the substrate 825. The path of movement of the target 830 is not limited to translation along the path of the substrate 825. The target 830 may rotate along its longitudinal axis, may translate (back and forth) along the path of the substrate, may translate along a path perpendicular to the path of the substrate, or may move in a circular path in a plane parallel to the substrate 825. The target 830 does not have to be cylindrical, but may be planar, or of any shape necessary to deposit the desired layer with the desired properties. Also, each deposition station may have multiple targets and / or the targets may be moved between stations depending on the desired process.

[0119] The total synthetic membrane system 800 further includes various vacuum pumps, gas inlets, pressure sensors, etc. for creating and maintaining a controlled ambient environment within the system. These components are not shown, but would be recognized by one of ordinary skill in the art. The system 800 is controlled by a controller, such as, for example, a computer system, shown in FIG. 8B as an LCD and keyboard 835. One of ordinary skill in the art would recognize that embodiments of the invention utilize various processes that utilize data stored in or transferred through one or more computer systems. Embodiments of the invention also relate to devices, such as computers and microcontrollers, for carrying out such processes. Such devices and processes may be used to deposit electrochromic materials in accordance with the methods of the invention and devices designed to carry out the methods. The controller of the invention may be specially constructed to accomplish the required purposes or may be a general-purpose computer selectively activated or reconfigured by computer programs and / or data structures stored on the computer. The processes described herein are not inherently related to any particular computer or other apparatus. In particular, various general purpose machines may be utilized with programs written in accordance with the teachings herein, or it may prove convenient to construct more specialized apparatus to perform and / or control the required methods and processes.

[0120] As mentioned above, the various stations of the total synthesis film system of the present invention may be modular, but when connected, form a series of systems that create and maintain a controlled ambient environment for processing substrates at the various stations in the system. FIG. 8C shows a total synthesis film system 800a. System 800a is similar to system 800, but in this example, each station is modular, specifically EC layer station 806a, IC layer station 806b, and CE layer station 806c. Although modularity is not required, it is convenient because the total synthesis film system can be assembled as needed to meet customer needs and newly developed processing techniques. For example, FIG. 8D shows a total synthesis film system 800b with two lithium deposition stations 807a and 807b. System 800b is equipped to carry out, for example, a method according to the present invention as described above, for example, the dual lithiation method described with reference to FIG. 7C. System 800b may also be used to perform the single lithiation method described with reference to Figure 7D, for example, by utilizing only lithium station 807b during substrate processing. However, in a modular format, for example, for processes in which single lithiation is desired, one of the lithiation stations is not required and system 800c, as shown in Figure 8E, is utilized. System 800c includes only one lithium deposition station 807.

[0121] Systems 800b and 800c further include a TCO layer station 808 for depositing a TCO layer on the EC stack. Additional stations can be added to the total composite film system depending on the processing required, for example, stations for cleaning processes, laser scoring, capping layer processing, MTC processing, etc.

[0122] Although the invention has been described above in sufficient detail to give a clear understanding, it is to be understood that the described embodiments are to be considered as illustrative only and not limiting, and that modifications and variations within the scope of the appended claims will be apparent to those skilled in the art. [Item 1] 1. An electrochromic window, comprising: (a) an architectural glass substrate; (b) a laminate provided on the architectural glass substrate; The stack comprises: (i) an electrochromic layer of tungsten oxide; (ii) a lithium ion conducting layer of a solid, inorganic material; and (iii) a counter electrode layer of tungsten nickel oxide; the ion-conducting layer separates the electrochromic layer and the counter electrode layer; The electrochromic window has a total of less than about 0.045 visible defects per square centimeter in any portion of the electrochromically active area. [Item 2] 2. The electrochromic window of claim 1, wherein the electrochromic layer comprises WOx, where x is less than 3.0 and at least 2.7. [Item 3] 2. The electrochromic window of claim 1, wherein the tungsten oxide is substantially nanocrystalline in morphology. [Item 4] 2. The electrochromic window of claim 1, wherein the electrochromic layer has a thickness between about 200 nm and about 700 nm. [Item 5] 2. The electrochromic window of claim 1, wherein the electrochromic layer and the counter electrode layer each comprise lithium ions. [Item 6] 2. The electrochromic window of claim 1, wherein the ion conductive layer comprises aluminum silicon oxide. [Item 7] 2. The electrochromic window of claim 1, wherein the ion-conducting layer has a thickness between about 10 nm and about 100 nm. [Item 8] 2. The electrochromic window of claim 1, wherein the counter electrode layer has a thickness between about 150 nm and about 350 nm. [Item 9] 2. The electrochromic window of claim 1, wherein the ratio of the thickness of the electrochromic layer to the thickness of the counter electrode layer is between about 1.7:1 and 2.3:1. [Item 10] 2. The electrochromic window of claim 1, further comprising a first transparent conductive oxide layer in electrical contact with the electrochromic layer and a second transparent conductive oxide layer in electrical contact with the counter electrode layer. [Item 11] Item 11. The electrochromic window of item 10, wherein the first transparent conductive oxide layer and the second transparent conductive oxide layer each have a sheet resistance of between about 5 ohms / square and about 30 ohms / square. [Item 12] 11. The electrochromic window of claim 10, wherein the laminate comprises two transparent conductive oxide layers, one of which is in electronic contact with the electrochromic layer and the other of which is in electronic contact with the counter electrode layer, and the two transparent conductive oxide layers have approximately the same sheet resistance. [Item 13] 2. The electrochromic window of claim 1, wherein the architectural glass substrate is at least about 20 inches wide. [Item 14] Item 1. The electrochromic window of item 1, having less than about 0.04 visible pinhole defects per square centimeter. [Item 15] Item 1. The electrochromic window of item 1 having less than about 0.005 visible short-circuit type defects per square centimeter. [Item 16] Item 1, wherein the electrochromic window develops a number of invisible short-circuit type defects such that the electrochromic window has a leakage current of less than about 5 μA / cm2 at a bias of ±2V. [Item 17] (a) an architectural glass substrate; (b) a laminate provided on the architectural glass substrate; The stack includes: (i) an electrochromic layer of tungsten oxide; (ii) a lithium ion conducting layer of a solid, inorganic material; and (iii) a counter electrode layer of substantially amorphous tungsten nickel oxide; An electrochromic window, wherein the ion conductor layer separates the electrochromic layer and the counter electrode layer. [Item 18] Item 18. The electrochromic window according to item 17, wherein the lithium ion conducting layer of solid and inorganic material comprises aluminum silicon oxide. [Item 19] 18. The electrochromic window of claim 17, having a total of less than about 0.2 visible defects per square centimeter of electrochromic active area. [Item 20] Item 18. The electrochromic window of item 17, wherein the counter electrode layer comprises a substantially amorphous nickel tungsten oxide having an atomic ratio between tungsten and nickel of between about 0.15 and 0.35. [Item 21] Item 18. The electrochromic window of item 17, wherein the counter electrode layer has a thickness between about 150 nm and about 350 nm. [Item 22] 18. The electrochromic window of claim 17, wherein the ratio of the thickness of the electrochromic layer to the thickness of the counter electrode layer is between about 1.7:1 and 2.3:1. [Item 23] Item 18. The electrochromic window of item 17, wherein the electrochromic layer comprises WOx, where x is less than 3.0 and at least 2.7. [Item 24] 24. The electrochromic window of claim 23, wherein the WOx is substantially nanocrystalline in morphology. [Item 25] Item 18. The electrochromic window of item 17, wherein the electrochromic layer has a thickness between about 200 nm and about 700 nm. [Item 26] Item 18. The electrochromic window of item 17, wherein the ion-conducting layer has an atomic ratio between silicon and aluminum of between about 5:1 and 20:1. [Item 27] Item 18. The electrochromic window of item 17, wherein the ion-conducting layer has a thickness between about 10 nm and about 100 nm. [Item 28] Item 18. The electrochromic window of item 17, further comprising a first transparent conductive oxide layer in electrical communication with the electrochromic layer and a second transparent conductive oxide layer in electrical communication with the counter electrode layer. [Item 29] Item 29. The electrochromic window of item 28, wherein the first transparent conductive oxide layer and the second transparent conductive oxide layer each have a sheet resistance of between about 5 ohms / square and about 30 ohms / square. [Item 30] 29. The electrochromic window of claim 28, wherein the laminate comprises two transparent conductive oxide layers, one of which is in electronic contact with the electrochromic layer and the other of which is in electronic contact with the counter electrode layer, and the two transparent conductive oxide layers have approximately the same sheet resistance. [Item 31] Item 18. The electrochromic window of item 17, wherein the architectural glass substrate is at least about 20 inches wide. [Item 32] 1. A method for manufacturing an electrochromic window, comprising the steps of: (a) depositing, on a substrate, (i) an electrochromic layer of a solid, inorganic material, (ii) an ion-conducting layer of a solid, inorganic material, and (iii) a counter electrode layer of a solid, inorganic material to form a laminate, the ion-conducting layer separating the electrochromic layer and the counter electrode layer; (b) performing a multi-step thermochemical conditioning process including heating the laminate in an environment substantially free of components that react with one or more layers of the laminate, and heating the laminate in an environment containing a substance that reacts with one or more layers of the laminate. [Item 33] The step of performing a multi-stage thermochemical conditioning process includes: (i) heating the laminate in an inert environment; (ii) heating the laminate in a controlled oxygen-containing environment; (iii) heating in air. [Item 34] 33. The method according to item 32, wherein the sequentially deposited electrochromic layer, the ion conductor layer, and the counter electrode layer are each deposited using a single total synthetic film system, and the substrate is not removed from the total synthetic film system at any time during the sequential deposition of the electrochromic layer, the ion conductor layer, and the counter electrode layer. [Item 35] 35. The method according to item 34, wherein at least one of the processes included in the multi-stage thermochemical conditioning is carried out outside the total synthetic membrane system. [Item 36] 36. The method of claim 35, wherein the substrate is heated in air after being removed from the total composite film system at a temperature of at least about 80°C. [Item 37] 1. A method for fabricating an electrochromic device on a substrate, comprising the steps of: (a) depositing an electrochromic layer; (b) lithiating the electrochromic layer; (c) depositing an ion conducting layer; (d) depositing a counter electrode layer that reversibly exchanges lithium ions with the electrochromic layer during operation of the electrochromic window; and (e) lithiating the counter electrode layer, By performing steps (a) through (e), a stack is produced on the substrate, with the ion conductor layer separating the electrochromic layer and the counter electrode layer. [Item 38] 38. The method of claim 37, wherein the step of lithiating the electrochromic layer comprises depositing lithium directly onto the electrochromic layer. [Item 39] 38. The method of claim 37, wherein the step of lithiating the counter electrode layer comprises depositing lithium directly onto the counter electrode layer. [Item 40] Item 38. The method according to item 37, wherein steps (d) and (e) are performed before step (c), and steps (a) and (b) are performed after step (c). [Item 41] Item 38. The method of item 37, wherein the electrochromic layer comprises WOx, where x is less than 3.0 and at least 2.7. [Item 42] 42. The method of claim 41, wherein the WOx is substantially nanocrystalline in morphology. [Item 43] Item 38. The method of item 37, wherein the counter electrode layer comprises nickel tungsten oxide. [Item 44] 44. The method of claim 43, wherein the amount of lithium, by mass, deposited on the counter electrode layer in step (d) is between about 1.5 and 2.5 times the amount of lithium, by mass, deposited on the electrochromic layer in step (b). [Item 45] 38. The method of claim 37, wherein when depositing lithium directly onto the electrochromic layer, depositing at least an amount of lithium sufficient to compensate for substantially all of the blind charge contained in the electrochromic layer. [Item 46] 38. The method of claim 37, wherein the lithium deposited in one or both of steps (b) and (d) is deposited by physical vapor deposition. [Item 47] Item 47. The method according to item 46, wherein the lithium deposited by physical vapor deposition in at least one of steps (b) and (d) is deposited in a total synthesis deposition system using two or more lithium targets aligned in series and offset from each other along the path of movement of the substrate. [Item 48] 47. The method of claim 46, wherein the lithium deposited using physical vapor deposition in at least one of steps (b) and (d) is deposited while the substrate moves back and forth through a lithium deposition station. [Item 49] 38. The method of claim 37, wherein the lithium deposited in one or both of steps (b) and (d) is deposited at a rate slow enough such that the deposited lithium is substantially entirely incorporated within the electrochromic layer or the counter electrode layer before deposition of the lithium is completed. [Item 50] 38. The method of claim 37, wherein the thickness of the electrochromic layer and the counter electrode layer does not vary by more than about 4% from the as-deposited thickness after lithiation upon electrochemical cycling of the electrochromic device. [Item 51] 38. The method of claim 37, wherein the electrochromic layer, the ion-conducting layer, and the counter electrode layer are each solid layers. [Item 52] 38. The method of claim 37, wherein the electrochromic layer, the ion-conducting layer, and the counter electrode layer each consist solely of inorganic materials. [Item 53] 38. The method of claim 37, wherein depositing the electrochromic layer comprises depositing the electrochromic layer to a thickness between about 200 nm and about 700 nm. [Item 54] 38. The method of claim 37, wherein the step of depositing an ion conducting layer comprises depositing a material selected from the group consisting of tungsten oxide, tantalum oxide, niobium oxide, and silicon aluminum oxide. [Item 55] 38. The method of claim 37, wherein depositing the ion conductor layer comprises depositing the ion conductor layer to a thickness between about 10 nm and about 100 nm. [Item 56] 38. The method of claim 37, wherein depositing the counter electrode layer comprises depositing a layer of tungsten nickel oxide. [Item 57] 57. The method of claim 56, wherein the layer of nickel tungsten oxide is substantially amorphous. [Item 58] 57. The method of claim 56, wherein depositing the counter electrode layer comprises sputtering a target containing tungsten in nickel at a concentration between about 10 and about 40 atomic percent in nickel in an oxygen-containing environment to produce the layer of tungsten nickel oxide. [Item 59] 38. The method of claim 37, wherein depositing the counter electrode layer comprises depositing the counter electrode layer to a thickness between about 150 nm and about 350 nm. [Item 60] 38. The method of claim 37, wherein the electrochromic layer comprises tungsten oxide and the counter electrode layer comprises tungsten nickel oxide, and the ratio of the thickness of the electrochromic layer to the thickness of the counter electrode layer is between about 1.7:1 and 2.3:1. [Item 61] Item 38. The method of item 37, further comprising depositing a transparent conductive oxide layer on the stack. [Item 62] 38. The method of claim 37, wherein the substrate comprises architectural glass. [Item 63] Item 38. The method of item 37, wherein the substrate is at least about 20 inches wide. [Item 64] 38. The method of claim 37, carried out under conditions such that the electrochromic window has less than about 0.04 visible pinhole defects per square centimeter. [Item 65] 38. The method of claim 37, carried out under conditions such that the electrochromic window has less than about 0.005 visible short-type defects per square centimeter. [Item 66] Item 38. The method of item 37, performed under conditions such that the electrochromic window develops a number of invisible short-type defects resulting in a leakage current of less than about 5 μA / cm2 at a bias of ±2 V. [Item 67] 1. A method for manufacturing an electrochromic window, comprising the steps of: 1. A method of manufacturing a semiconductor device comprising the steps of sequentially depositing on a substrate (i) an electrochromic layer of tungsten oxide, (ii) a lithium ion conductor layer of a solid, inorganic material, and (iii) a counter electrode layer of substantially amorphous tungsten nickel oxide to form a laminate, said ion conductor layer separating said electrochromic layer and said counter electrode layer. [Item 68] Item 68. The method according to item 67, wherein the sequentially deposited electrochromic layer, the ion conductor layer, and the counter electrode layer are each deposited using a single total synthetic film system, and the substrate is not removed from the total synthetic film system at any time during the sequential deposition of the electrochromic layer, the ion conductor layer, and the counter electrode layer. [Item 69] Item 68. The method of claim 67, wherein depositing the substantially amorphous nickel tungsten oxide counter electrode layer comprises producing a nickel tungsten oxide having an atomic ratio between tungsten and nickel of between about 0.15 and 0.35. [Item 70] Item 68. The method of claim 67, wherein the depositing the ion conducting layer comprises forming a silicon aluminum oxide having an atomic ratio between silicon and aluminum of between about 5:1 and 20:1. [Item 71] 68. The method according to item 67, wherein the electrochromic layer comprises WOx, where x is less than 3.0 and at least 2.7. [Item 72] 72. The method of claim 71, wherein the WOx is substantially nanocrystalline in morphology. [Item 73] Item 68. The method of claim 67, wherein (i) the tungsten oxide electrochromic layer, (ii) the solid and inorganic lithium ion conducting layer, and (iii) the substantially amorphous tungsten nickel oxide counter electrode layer are each deposited by physical vapor deposition. [Item 74] Item 73. The method of claim 72, wherein depositing the counter electrode layer comprises sputtering a target containing tungsten in nickel at a concentration between about 10 atomic concentration and about 40 atomic concentration in nickel in an oxygen-containing environment to produce the layer of tungsten nickel oxide. [Item 75] Item 68. The method of claim 67, wherein depositing the counter electrode layer comprises depositing the counter electrode layer to a thickness between about 150 nm and about 350 nm. [Item 76] 68. The method according to item 67, wherein the ratio between the thickness of the electrochromic layer and the thickness of the counter electrode layer is between about 1.7:1 and 2.3:1. [Item 77] Item 68. The method of claim 67, wherein depositing the counter electrode layer comprises depositing nickel tungsten oxide at a pressure between about 1 mTorr and about 50 mTorr. [Item 78] Item 68. The method of claim 67, further comprising depositing a transparent conductive oxide layer on the stack. [Item 79] 68. The method of claim 67, wherein the substrate comprises architectural glass.

Claims

[Claim 1] A first transparent conductive layer; an electrochromic layer comprising a tungsten oxide based electrochromic material doped with one or more materials selected from the group consisting of molybdenum, vanadium, and titanium; a counter electrode layer comprising a nickel oxide based counter electrode material doped with tungsten and tantalum; A second transparent conductive layer. Electrochromic element.

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