JPH08262502A - Iridium oxide film for electrointerchangeable device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a nitrogen contained iridium oxide film active in an electro-enantiotropic state and used for a transparent or opaque electro- enantiotropic device by sticking an iridium target by sputtering in a sputter chamber having a base material. SOLUTION: A transparent base material is generally nonconductive. In the case of adjusting an electro-enantiotropic device, it is desirable that the base material is first coveted with a conductive film. This film is formed of fluorine doped tin oxide usually called indium/tin oxide(ITO). A conductive film such as ITO is stuck onto a polymer base material by direct current sputtering. The covered base material is alternately rotated through a rapid metal sputter area and powerful reactive plasma. A DC magnetron sputter cathode functions in a partial pressure separation regime in combination with a erotating cylindrical workpiece transfer system. The ITO film with required visible transmissiveness and sheet resistance is thus adjusted.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION This invention relates generally to the field of electrochromic cells, and more particularly to using iridium oxide as a complementary electrochromic film and as a charge-balancing counter electrode. The field of transparent electrochromic devices.

[0002] Conventional electrochromic cells are persistent electrochromic materials, ie, the application of an electric field of a given polarity and sufficient voltage to change from a highly transparent non-absorbing state to a less transparent absorbing or reflecting state. Having a thin film of material that is responsive. The film of electrochromic material remains in a substantially low transmission state after the electric field is interrupted. When an electric field of opposite polarity is applied to this electrochromic material, it returns to its original high transmission state. A film of an electrochromic material that is both an ionic and an electrical conductor is in ionic conductive contact, preferably in direct physical contact, with a layer of ionic conductive material. The ion-conducting material can be a solid, liquid or gel. The electrochromic film and the ion conductive layer are provided between two electrodes to form a cell. In some applications, a complementary electrochromic film is used to form the cell, and in other applications, an optical electrochromic film is used instead of the complementary electrochromic film to form the cell. Inactive (passi
ve) Film or metal is used.

When a voltage is applied between the two electrodes, the ions are conducted through the ion conducting layer. The electrode adjacent to the film of electrochromic material is the cathode,
If the electrochromic material is cathodically colored, application of an electric field to this material causes a darkening of the film. Reversing the polarity of the electric field causes a reversal of the electrochromic properties, causing the film to revert to the highly transparent state. Traditionally, cathodically coloring electrochromic materials, usually tungsten oxides or their compounds, are deposited on a glass substrate precoated with an electrically conductive film such as tin oxide or indium / tin oxide (ITO). One electrode is formed by being attached. In some electrochromic devices, the counter electrode is a carbon paper construction backed by a similar tin oxide or indium / tin oxide coated glass substrate or metal plate.

Schiavone is a journal
Of the Electrochemical Society, No. 1
28, No. 6, 1212-1214, June 1981, the deposition of electrochromic iridium oxide by reactive sputtering of iridium targets is described. Iridium oxide films are deposited by reactive radio frequency sputtering of iridium targets in pure oxygen to deposit the film in the fully colored state.

Kang and Shay were sputtered blue in Journal of the Electrochemical Society, Volume 130, No. 4, p. 766, et al., April 1983. The iridium oxide film will be described. The properties are compared to those of black sputtered and anodically grown iridium oxide films. Blue iridium oxide film has 2
It is deposited by reactive dc sputtering of iridium in an 80/20 argon / oxygen gas mixture on a glass substrate held at 38 ° K. The method used by the author was a 15 minute target pre-sputter step in pure argon followed by a 25 minute in-situ substrate cleaning step,
And another 10 minute pre-sputter step in the argon / oxygen gas mixture used for the actual coating. As an electrochromic display electrode, a blue sputtered iridium oxide film is described as having an improved open circuit erasable and written-state memory, and an improved appearance. Cogan et al., SPIE, Volume 823, Volume 182.
Issue, 1987, indium / tin oxide
An electrochromic device having an (ITO) coated glass sheet, an electrochromic film of tungsten oxide and iridium oxide, and a polymer electrolyte of poly-2-acrylamido-2-methylpropanesulfonic acid (polyAMPS) is described.

US Pat. No. 4,350,41 to Takahashi et al.
No. 4 is a pair of electrodes, iridium hydroxide and /
Or an oxidizable film of nickel hydroxide, a reducible film of tungsten oxide and / or molybdenum oxide, and an insulating film between those films that allow the conduction of protons but inhibit the conduction of electrons (eg, tantalum oxide, zirconium). Disclosed is a solid state electrochromic device having oxide, niobium oxide, alumina, magnesium fluoride, silicon oxide, titanium oxide, hafnium oxide or yttrium oxide).

US Pat. No. 5,327,28 to Corgan et al.
No. 1 describes a solid polymer electrolyte for electrochromic devices laminated between an amorphous tungsten trioxide coated indium / tin oxide coated glass substrate and an iridium oxide coated indium / tin oxide coated glass substrate. To do.

[0008]

The present invention is directed to nitrogen-containing iridium oxide films. More particularly, the present invention relates to electrochromatically active nitrogen-containing iridium oxide films for use in transparent and opaque electrochromic devices. This film is deposited by sputtering an iridium target in a sputter chamber with a substrate, the film being deposited under conditions such that the nitrogen in the oxygen-containing reactive gas is incorporated into the iridium oxide. It No special means is required for the attachment method, for example:
No low temperatures or extreme preconditioning of the iridium sputter target is required. Iridium oxide films containing nitrogen have been found to exhibit desirable properties when used as complementary electrochromic films in solid state electrochromic devices. Nitrogen-containing iridium oxide films are electrochemically precharged (prechar
When ged (reduced), such films are found to be more stable than iridium oxide films containing no nitrogen. This is evidenced by the low change in permeability after application to the electric field. That is, no self-darkening of the film is observed after application of the electric field when exposed to ambient conditions. Such films are resistant to oxidation when exposed to air. In addition, a high deposition rate of 100 Å / min for nitrogen-containing iridium oxide films is obtained.

The substrate for the iridium oxide film of the present invention is, in one embodiment, suitable for providing lenses for use in glass or plastic, preferably spectacles, such as polymer lenses prepared from synthetic optical lenses. Transparent materials such as transparent materials, especially transparent materials. Polymer lenses have either a normal refractive index (about 1.48 to 1.5), a relatively high refractive index (about 1.60 to 1.75), or a medium refractive index (about 1.48 to 1.5), depending on the end use. 1.55
˜1.56). Alternatively, the polymer lens is anywhere between about 1.48 and 1.75 (eg, about 1.5
It may have a refractive index of 0 to 1.66).

Synthetic polymer substrates that can be used as lens materials include, but are not limited to:
Thermoplastic polycarbonates such as carbonate-bonded resins derived from bisphenol A and phosgene, sold under the trademark "Lexsan"; polyesters such as the materials sold under the trademark "Mylar"; Poly (methyl methacrylate), such as the material sold under the trademark; and sold under the trademark "CR-39",
Polymer of polyol (allyl carbonate) monomer, especially diethylene glycol bis (allyl carbonate). The above-mentioned monomer / resin copolymers may also be used as the lens material. In addition, transparent and opaque polymeric substrates known to those skilled in the art for use in various optical and non-optical applications can also be used as substrates for nitrogen-containing iridium oxide films.

Substrates on which the iridium oxide film is deposited, such as transparent substrates, are generally not electrically conductive. When preparing an electrochromic device, the substrate is
Preferably it is first coated with an electrically conductive film. The electrically conductive film can be any known to those skilled in the art for use as an electrically conductive film in an electrochromic device. Typically, such films are transparent thin films of metal or metal oxide. For example, fluorine-doped tin oxide or tin-doped indium oxide, commonly referred to as ITO (indium / tin oxide). It is preferably ITO having a weight ratio of indium and tin of about 90:10. Other materials such as antimony-doped tin oxide and aluminum-doped zinc oxide can be used as the electrically conductive film. Preferably, the film has a sheet resistance of 10-30 ohms / square. The thickness of the electrically conductive film is preferably in the range of 1300 to 4000 angstroms, for example 2000 to 4000 angstroms, and more preferably 2500 to 2800 angstroms. And preferably, the film has a sheet resistance of about 18-30 ohms / square for desirable electrical conductivity.

The electrically conductive film can be applied by various methods known to those skilled in the art, so long as the substrate is not adversely affected by the method. High temperature pyrolysis may be used to deposit the electrically conductive film on the glass. However, such methods are generally not suitable for lower melting polymer substrates. The preferred method for depositing an electrically conductive film such as ITO on a polymer substrate is direct current
(DC) Sputtering. In particular, U.S. Pat. No. 4,851,0
95 and 5,225,057 and co-pending US patent application Ser. No. 08/08/19, filed Aug. 19, 1994.
DC magnetron reactive sputtering (MSVD) such as the high deposition rate, low temperature method, Meta Mode ^R sputtering system described in 293,129. Vacuum web coating using a cooling drum IT on plastic substrate
Another method of coating O.

In the above mentioned '095 and' 097 patents, the substrate to be coated is rotated alternately through a high velocity metal sputter region and an intense reactive plasma. The DC magnetron sputter cathode works in a partial pressure separation regime in combination with a rotating cylindrical workpiece transfer system. Using such techniques, ITO films with a visible transmission of greater than 80% and a sheet resistance of 18-20 ohms / square can be prepared at 20 ° C.

Generally, the adhesion of electrically conductive metal oxide films to plastic substrates is not suitable due to their durability in the environment and the long circulation of the electrochromic device (coloring / decoloring circulation). In such a case, it is preferable to provide an adhesion-improving polymer undercoat at the interface between the substrate and the electrically conductive film to improve the adhesion of the electrically conductive film to the surface of the plastic substrate. In addition, the polymeric primer helps prevent cracking and / or cracking of plastic substrates and electrically conductive films. Preferred plasmamers for polymer substrates prepared from optical resins containing CR-39 ^R allyl diglycol carbonate monomer are acrylate copolymers, preferably acrylic acid and cyanoethyl acrylate, hydroxyethyl acrylate, methyl methacrylate and such substituted acrylates. A copolymer with a substituted acrylate, such as a mixture of Preferably, the substituted acrylate is methyl methacrylate and the molar ratio of acrylic acid to the substituted acrylate, such as methyl methacrylate, is about 3: 1 to about 1: 3.

Preferably, the primer is applied as a solution of the monomer in an organic solvent to the surface of the plastic substrate by dip, flow or other conventional application technique. The organic solvent is then evaporated and the polymeric primer is cured at slightly elevated temperature, typically at about 160-200 ° F (about 80-92 ° C) for about 8 hours. Generally, the monomer solution contains an initial amount of free radical initiator such as azobisisobutyronitrile. The monomer solution may also include cycloaliphatic diepoxide to crosslink the acrylate copolymer. The diepoxide referred to here is
2- [3,4-epoxycyclohexyl-5,5-spiro-3,4-epoxy] cyclohexane-metadioxane; bis [3,4-epoxycyclohexyl] adipate; and 3,4-epoxycyclohexyl-3,4- Includes epoxy-cyclohexane-carboxylate. Preferably, the monomer solution may include a catalyst such as dibutyltin dilaurate (DBTDL) or uranyl nitrate to cure the primer.

Organic solvents used for the monomer solution include cyclohexanone, 1-propanol, 1-butanol,
It can be a mixture of acetone and such a solvent. The preferred organic solvent is 1-propanol. The method of applying the primer is to dip the plastic substrate in the monomer solution of the primer, remove the substrate from the solution, and dry and cure the primer coating on the substrate. Then, the undercoating agent is removed by polishing from the surface not covered with the electrically conductive film. Another method of applying a primer to a plastic substrate is to spin coat a monomer solution on one surface of the substrate and dry and cure the resulting primer coating. Preferably, the primer coating has a thickness of about 0.01 to 0.50 microns, more preferably about 0.5.
It is in the range of 29 to 0.46 micron.

To prepare a transparent electrochromic device, a transparent plastic substrate coated with two primed electrically conductive films is combined. The electrically compatible film is deposited on the electrically conductive film of one plastic substrate and the complementary electrochromic film is deposited on the electrically conductive film of the other plastic substrate. molybdenum
(MoO ₃ ), tungsten (WO ₃ ), vanadium (V
₂ O ₅ ), niobium (Nb ₂ O ₅ ), titanium (TiO ₂ ), chromium (Cr
₂ O ₃ ), praseodymium (PrO ₂ ), and ruthenium (Ru
Of the various known electrochromic materials such as O ₂ ) oxides, tungsten oxide and compounds of tungsten oxide are preferred. In addition, MoWO ₃ , NbWO ₃ ,
K _1-x WO ₃ and Na _1-x WO ₃ (where x is less than 1)
Ternary metal oxides such as and tungsten bronze may be used.

The tungsten oxide may be deposited on the substrate by thermal evaporation of the tungsten oxide. However, US Pat. Nos. 4,851,095 and 5,2
It is preferred to deposit by direct current (DC) magnetron sputtering of tungsten in a noble gas / oxygen atmosphere at high total gas pressures (greater than 20 mtorr) using a device such as the Metamode ^R system described in 25,057. The thickness of the electrochromic, eg tungsten oxide film is preferably 3000 to 5000 angstroms, more preferably about 3700 ± 5000 angstroms. Electrochromic films, such as tungsten oxide, are transparent (highly transparent) in the as-deposited state.

According to an embodiment of the present invention, another subbed and electrically conductive film coated substrate is further coated on the electrically conductive film with a film of nitrogen-containing iridium oxide. The iridium oxide film can be deposited by radio frequency (rf) or direct current (DC) magnetron sputtering. The sputter gas is oxygen,
Includes nitrogen (or a nitrogen-containing gas) and an inert gas such as argon, neon, krypton or xenon. From the viewpoint of cost, argon is preferred as the inert gas. The partial pressure of nitrogen is preferably equal to or above the partial pressure of the inert gas, eg argon. Furthermore, high partial pressures of oxygen are used in this system. Preferably, the partial pressure of oxygen is 20-50% of the total gas pressure. The flow ratio of oxygen to nitrogen is about 2 to 8: 1, for example 4 to 7: 1.
It has been found that the amount of nitrogen in the iridium oxide film increases as the relative amount of oxygen increases with respect to the inert gas, eg argon.

In the electrochromic film, the complementary electrochromic film of nitrogen-containing iridium oxide can be deposited using the Metamode ^R system. It includes a DC magnetron reactive sputter deposition system in which the reactive gas is separated from the non-reactive gas by a low pressure region. Deposition of the metal species occurs on the substrate and moves and / or rotates between the deposition area of the sputter target and the reactive gas plasma area.
The reactive gas region consists of positively biased electrodes,
This results in the formation of a plasma rich in reactive ionic species, which bombards the newly deposited metal on the substrate, thereby forming a compound of the metal such as oxide, nitride, oxynitride or combinations thereof. It This system adheres to the desired film thickness-
It can be simply described as a sequence of reaction-attachment-reaction.

The total system gas pressure in the system is 5 to 100,
For example, it is in the range of 40 to 75 millitorr. The reactive gas partial pressure in the system is in the range of 7-40 mtorr. Nitrogen or a nitrogen-containing gas can be introduced at any suitable location in the Metamode ^R system. For example, in the attachment area, the reaction area or any inert attachment area. Typical cathode power and ion source flow are in the range of 1-5 kilowatts and 1-3 amps, respectively. Optimal conditions can be determined through statistical design for nitrogen-containing iridium oxide films.

Sputtering of iridium oxide is carried out using an iridium target of suitable size and shape for the size and shape of the substrate to be coated. A preferred spacing is, for example, 3 to 6 inches (7.62 to 15.24 cm), but the spacing may be in close proximity to deposit a uniform coating on the substrate. Preferably, the sputter chamber is evacuated to less than 10 ^-5 torr, preferably less than 10 ^-6 torr prior to introducing the reactive gas composition of the sputtering atmosphere. Deposition of the nitrogen-containing iridium oxide sputters the iridium target and, depending on the particular sputtering equipment used, the sputtered iridium with a reactive gas, i.e., one containing an oxidizing atmosphere, preferably an oxygen- and nitrogen-containing gas, About 5-100, for example 40
It is carried out by contacting at a chamber pressure in the range of ~ 75 mtorr.

According to the present invention, the presence of nitrogen in the iridium oxide film renders the film more stable to loss of transparency when electrochemically reduced and exposed to air. For example, self-darkening or erasing for a short time, eg 30 minutes, is minimal.
In other words, the nitrogen-containing iridium oxide film shows a significant improvement in retaining the high bleached state optical transmission. In addition, if the nitrogen-containing iridium oxide film is electrochemically reduced, it will not oxidize again when exposed to air.

The reactive gas atmosphere in the sputter chamber contains a sufficient amount of nitrogen to result in the incorporation of a stabilizing amount of nitrogen into the iridium oxide film. That is, the film contains sufficient nitrogen to prevent significant changes in permeability after being electrochemically precharged.
In other words, the amount of nitrogen incorporated into the iridium oxide film is sufficient to stabilize the film so that its permeability does not change significantly during electrochemical reduction. Nitrogen in the sputter chamber atmosphere can be as pure nitrogen gas or in the form of air or other nitrogen-containing gas composition such as ammonia. The nitrogen source is filled into the chamber separately or sequentially, or as part of an oxygen source that provides an oxidizing atmosphere.

The deposited iridium oxide film contains at least 2 atomic%, more preferably at least 5, most preferably at least 8 atomic% nitrogen. The iridium oxide film of the present invention contains about 2-20, such as 4 or 8-18, or 12-18 atomic% nitrogen. However, films containing more than 20 atomic% nitrogen are also considered here. The thickness of the nitrogen-containing iridium oxide film is preferably about 300-800.
Angstrom range. These films are from Rutherford Backscatter Spectrometry
(RBS), which is the atomic number density (atoms / c
The analytical results are provided as m ² ) and are referred to herein as atomic%.
In one embodiment, the film is said to contain 66-68 atomic% oxygen and 4-12 atomic% nitrogen, and the atomic oxygen to iridium ratio is in the range of about 2-3.

The amount of nitrogen incorporated into the iridium oxide film can be controlled by changing the flow rate (or partial pressure) of nitrogen while keeping other processing conditions the same. Another way to control the amount of nitrogen incorporated into the film is to change the relative flow rate ratio of oxygen to an inert gas such as argon at a constant nitrogen flow rate. At present, the exact chemistry of nitrogen in iridium oxide films has not been established. Nitrogen is required to be present as elemental nitrogen or other forms of nitrides or oxynitrides.

It has been found that the amount of nitrogen in the iridium oxide film affects the electrochromic properties of the film. Switching speed, tinting efficiency (defined by the change in optical density versus charge density), charge capacity, and tinting / bleaching range all vary depending on the level of atomic nitrogen contained in the film.

If radio frequency (rf) magnetron sputtering is used to deposit the iridium oxide film, the power output can be selected in relation to the sputtering equipment, 100 to 135 watts, more preferably about 42 cm upon deposition. ^It can be about 125 watts for a target size of ² . The power density is preferably 1-5, more preferably 2-4, most preferably 2.5-3.5 watts / cm ² . Typically, the target and chamber are water cooled during the rf magnetron sputter coating deposition process. In the Metamode ^R system, the target alone is usually cooled with water.

Nitrogen-containing iridium oxide film coated on ITO coated substrate is galvanic electrostatically
(galvano static) or potential difference electrostatic (potentiostati
c) It may be electrochemically precharged using any of the techniques in an acid bath such as 0.1 molar Molar hydrochloric acid or 0.1 molar Molar sulfuric acid. In one embodiment, the cell structure has three electrodes. That is, the working electrode (WE) and the reference electrode (RE)
And a counter electrode (CE). The working electrode is a nitrogen-containing iridium oxide film. The reference electrode is a standard calomel electrode (SCE). And the counter electrode is a platinum foil with an area of 25 cm ² .

For standard calomel electrodes -0.5 to -0.
The amount of charge that is inserted and removed is approximately 13-40 mC using potentiometric electrostatic conditions with a voltage in the range of 1 volt.
/ Cm ² .

Electrochemical reduction can also be performed under galvanic electrostatic conditions including a current of about 1.5 × 10 ^-3 amps and a voltage limit set at 1.5 volts. The amount of charge inserted and removed under these conditions is about 23 mC / cm ² . A coulometer wired in connection with the WE can be used to measure the charge. The accumulated charge is about 1-40, preferably 15-29, more preferably 20-29 mC / cm ² .

A cell having an electrochromic film in a face-to-face relationship by assembling a pair of the plastic substrates after being primed, coated with an electrically conductive film and further coated with the electrochromic film. To form.
The cells may be provided by preferably providing a preformed sheet of ion-conducting polymer between two half cells and laminating the resulting assembly in an autoclave. The layer of ion-conducting material is preferably an ion-conducting polymer that adheres both electrochromic surfaces to form a laminated article.
In a preferred embodiment of the invention, the ionically conducting polymer electrolyte is a proton conducting polymer. Preformed sheet form is laminated between the 2-acrylamido-2-methylpropanesulfonic acid (AMPS ^R (Lubrizol trademark of)) and AMPS and copolymers substrate with various monomers or in situ, Used in the form of a liquid reaction mixture of monomers to be cast or cured. Preferred proton conducting polymer electrolytes according to the present invention are AMPS and N, N-dimethylacrylamide (DM).
It is a copolymer with A). Preferably, they are cast or cured in situ. Preferred AMPS and DMA
The copolymer with A has a molar ratio of A in the range of about 1: 3 to 1: 2.
Prepared from MPS and DMA monomers. The thickness of the polymer electrolyte is preferably 0.001-0.025 inch
(0.0254 to 0.625 mm), more preferably 0.00
It is 5 to 0.015 inches (0.127 to 0.381 mm). This is disclosed in US patent application Ser. No. 08 / 152,340, filed November 12, 1993, the disclosure of which is hereby incorporated by reference.

The AMPS / DMA copolymer proton conducting electrolyte is preferably cast in situ as a solution of 1-methyl-2-pyrrolidone (NMP) and the monomer in water. The monomer solution contains a photoinitiator for polymerizing the monomer by exposure to actinic radiation, preferably ultraviolet (UV) light. Preferred UV initiators include benzoin methyl ether and diethoxyacetophenone. The monomer solution is 0.005-0.025 inches (0.381-0.508 m) that is held in place with a commercially available sealant, such as "Toll Seal ^R " available from Varian Vacuum Products.
It can be poured between two separate electrical conductivity and electrical photochromic coated polymeric lens substrate assembled with Teflon ^R spacer m). Curved lenses typically have a diameter of about 70 mm and a thickness of 1-2 mm. For a pair of curved lens substrates, the monomer solution is poured onto the concave surface of one lens substrate and the convex surface of the other lens substrate is placed in contact with the monomer solution. In this way, the monomer solution is formed as a thin film between the lens substrates. Sufficient UV light exposure to cure the polymer electrolyte is about 30 minutes for mercury lamps and about 1 to about 1 for xenon lamps.
3 minutes. Although the above discussion is directed to curved substrates, the nitrogen-containing iridium oxide films of the present invention are also applicable to flat substrates used in applications other than lenses.

In addition to the ion-conducting polymer electrolytes described above, other materials may be used, such as hydrogen uranyl phosphate or materials containing polyethylene oxide / LiClO ₄ . In addition, LiNbO ₃ , LiBO ₃ , LiTaO ₃ ,
LiF, Ta ₂ O ₅ , Na ₂ AlF ₆ , Sb ₂ O ₅ · nH ₂ O + Sb ₂
O ₃ , Na ₂ O.11Al ₂ O ₃ , MgF ₂ , ZrO ₂ , Nb ₂ O ₅
Also, inorganic films such as Al ₂ O ₃ are considered for use as electrolyte materials.

The resulting electrochromic lens has a slight haze
(0.3-0.4%), but generally there are no cracks.
Electrical contact to the electrochromic device is preferably made using electrically conductive busbars. The optical transmission of the lens at 550 nm is about 75% or higher in the bleached state and in the voltage range of about +1.5 to -1.5 volts for a charge in the range of about 23 to 29 mC / cm ² . Have a minimum of about 10% in the darkened state. The charge capacity of such films can range from less than 3 to over 30 mC / cm ² . For electrochromic articles other than glasses, the transparency in the bleached state may be lower and the darkened state may be higher or lower.

[0036]

The present invention will be described in more detail by the following examples, which are intended to be illustrative, and numerical modifications and improvements thereof will be apparent to those skilled in the art.

Example 1 Polymer lens substrate having a diameter of 70 mm, 6 plano and a thickness of 2 mm
(CR-39 ^R monomer, manufactured by PPG Industry Co., Ltd.) was undercoated with a polymer undercoating agent composed of a copolymer of acrylic acid and methyl methacrylate (molar ratio 3: 1). The primed surface was then exposed to 90% by weight indium and 10% by weight tin from a target of 80% argon and 20%.
DC at 140 ° F (60 ° C) in an atmosphere of% oxygen
It was coated by depositing an electrically conductive layer of indium / tin oxide (ITO) about 2600-2800 angstroms thick by sputtering. Finally, the radio frequency on the primed and electrically conductive coated surface
A thin film of iridium oxide containing nitrogen was deposited by (rf) magnetron sputtering. The base pressure for sputter coating was 2 × 10 ^-3 Torr. Target is purity 9
It is 9.9% iridium metal and the target dimensions are 2.
It was 87 inches (7.3 cm). The distance from the target to the substrate was 6 inches (15.24 cm). The rf power was 125 watts and the power density was 3 watts / cm ² and lasted 44 minutes. Typical sputter rates were 9-15 Angstroms / minute. The nitrogen-containing iridium oxide film had a thickness of about 600 Å.

The coated sample was analyzed for optical transmission in the visible region. Then coat this coating with 1.5 × 10
^It was electrochemically precharged in a bath of 0.1 N hydrochloric acid (HCl) at a voltage limit of ^-3 amps steady-state current of 1.5 volts (V). The amount of charge inserted and removed is about 21 mC / c
It was m ² . After this galvanic electrostatic treatment, optical transmission and coating adhesion were measured. The deposited nitrogen-containing iridium oxide film had a phototopic permeability of about 40%. A charge of the film at 21 mC / cm ² after 3 electrochemical oxidation / reduction cycles gave about 75% phototopic permeability. The charge retention of the film was excellent. After 30 minutes of exposure to air, there was only 1% change in permeability in the hot topic area. In contrast, the iridium oxide film deposited without nitrogen changed 5-8%. For film adhesion after precharging, the crosshatch test, ASTM D3359, Method A, passed a rating of 5. Electrochemical experiments showed that the protons were able to successfully reverse the lattice of iridium oxide, with a charge exchange of about 23 mC / cm ² . Cyclic voltammogram of nitrogen-containing iridium oxide film
s) (CV) shows good stability after repeated cycling.

Then, 28% by weight of AMPS, 47% of DMA, 6% of 1-methyl-2-pyrrolidinone (NMP)
And AM prepared from a reaction mixture containing 19% water
PS / DMA copolymer thickness 0.020 inch (0.0
(051 mm) as the ion-conducting layer, and the iridium oxide coated lens was coated with a polymer substrate prepared from CR-39 ^R monomer, the undercoat and ITO described above.
Laminates with layers and a tungsten oxide coated lens with a tungsten oxide film about 3700 ± 500 Å thick. The electrochromic article exhibited 76% bleached state transmission and 25% darkened state transmission as measured by a Spectroguard Color System, Model 96 Spectral Photometer.

Example 2 US Pat. Nos. 4,851,095 and 5,225,0
C using the DC magnetron sputtering system described in No. 57.
R-39 was the ^R allyl diglycol carbonate monomer on a plastic substrate prepared from a resin composition containing the deposited nitrogen containing film iridium oxide. 12.75 x 5.25 x 0.25 inch (32.39 x
An iridium metal target of 13.34 x 0.64 cm) was used. The substrate had an area of 25 cm ² . The conditions of the deposition process used are shown in Table 1 below.

[0041]

[Table 1] Cathode output: 1K watt Sputter gas: Argon @ 100sccm Ion source current: 1 amp Reaction gas: Oxygen @ 850sccm Nitrogen gas flow rate: 110sccm Total gas pressure: 40m Torr Drum diameter: 34 inches (86.3cm) drum rotation : 100 rpm Distance between target substrates: 3 inches (7.6 cm) Iridium oxide film thickness: 600 angstrom Deposition rate: 100 angstrom / min (sccm = standard cubic centimeter / min)

The iridium oxide film was analyzed for nitrogen using Rutherford Backscatter Spectroscopy and found to contain 8% atomic nitrogen. The 600 Å film had 40% transmission as deposited. The film was electrochemically reduced in 0.1 M (Molelar) hydrochloric acid using a three-electrode Pontesio electrostatic technique.
-0.5V was applied to the sample (working electrode) with respect to a saturated calomel reference electrode. A 25 cm ² platinum foil was used as the counter electrode. The amount of injected charges is 750 mC (30 mC / c
m ² ). Then the charge is (for SCE) +1.0
It was extracted by applying V. This process was repeated 3-5 cycles before removing the sample from the acid solution. The discolored transmission of this sample was 70%.

The amount of charges injected into such a sample can be changed by controlling the potential difference static electricity. About 2
Charge levels of 3 to about 40 mC / cm ² are obtained by such a method.

Example 3 Using the DC magnetron sputtering unit described in Example 2, I having a sheet resistance of 5 ohm / square
An iridium oxide film was deposited on a 4 cm ² glass square with a TO electrically conductive coating. The nitrogen gas flow rate was kept constant at 220 sccm. However, the oxygen and argon flow rates were varied. The total flow rate of combined oxygen and argon gas was kept at 950 sccm. The total gas pressure was maintained at 40 mtorr by carefully adjusting the conductance of the high vacuum pump used to control the total gas pressure. Films prepared at the gas flow rates shown in Table 2 were analyzed by RBS for nitrogen. Table 2 shows the results.

[0045]

Table 2 Flow of film O ₂ Flow of N ₂ Film% T loss b Dynamic velocity ^a N% in dynamic velocity ^a (5 minutes) 1 600 220 5.0 3.8 3.8 800 220 220 8.0 2.0 3 850 220 220 9.0 1.7 4 890 220 220 110 ^a sccm (standard cm ³ / min) ^b Permeability

The results in Table 2 show that the amount of nitrogen contained in the iridium oxide film was increased from 5% to 11% when the oxygen flow rate was increased compared to the argon flow rate. .

These examples are presented to illustrate the invention without limiting its field of view. Various other materials and processes not specifically described will be apparent to those skilled in the art. For example, the counter electrode is not complementary but inactive
(passive), materials such as In ₂ O ₃ , fluorine-doped tin oxide, tin-doped iridium oxide (IT
O) and Nb ₂ O ₅ may be used. Organic electrochromic materials such as polyamylene and viologen (1,1-diheptyl-4,4-bipyridinium dibromide) can also be used in the electrochromic device of the present invention.

Although particular embodiments of the present invention have been described, these details are not to be construed as limiting the scope of the invention which falls within the scope of the appended claims.

 ─────────────────────────────────────────────────── --Continued Front Page (71) Applicant 595160008 Optical Coatings Laboratory Incorporated Optical Coatings Laboratory, Inc. 2789 North Point Parkway, Santa Rosa, Calif. 95407-7397 (72) Inventor Philip Sea You United States, 15239 United States, 15239 Kayuga Drive, Pittsburgh, Pennsylvania, 2134 (72) Inventor, David Bee Backfish, United States, 15146 Monroeville, Monroville, Pennsylvania, 2059 (72) Inventor, Nada A. O'Brien Maher, Santa Rosa, CA 95405, USA Drive 2322 (72) Inventor Bryant Pee Hichiwa 95405 Santa Rosa, California USA Presley Road 4100

Claims (27)

[Claims] 1. An electrochromatically active iridium oxide film containing iridium oxide and a stabilizing amount of nitrogen. 2. The stabilizing amount of nitrogen is about 2 to 20 atomic%.
The film according to claim 1, which is 3. The stabilizing amount of nitrogen is about 8-18 atom%.
The film according to claim 1, which is 4. The iridium oxide film comprises about 6
The film of claim 1 containing 6-68 atom% oxygen, 4-12 atom% nitrogen, and having an oxygen to iridium atom ratio in the range of about 2-3. 5. A) placing the substrate and the iridium metal target in close proximity in a vacuum chamber; b) sputtering the iridium metal target; and c) the sputtered iridium and oxygen and nitrogen containing gas. Providing a nitrogen-containing iridium oxide film on the surface of the substrate, the method comprising: contacting with a gas mixture comprising: thereby depositing the nitrogen-containing iridium oxide film on the target-facing surface of the substrate. Method. 6. The substrate and the iridium metal target are about 3
The method of claim 5, wherein the methods are separated by a distance of ~ 6 inches. 7. The method of claim 5, wherein the gas mixture comprises an inert gas. 8. The method of claim 7, wherein the nitrogen-containing gas is nitrogen, air or ammonia. 9. The method of claim 5, wherein the iridium metal target is sputtered using DC magnetron sputtering. 10. The method of claim 9, wherein the gas mixture contains argon. 11. Oxygen and nitrogen are separately introduced into the vacuum chamber, and the flow ratio of oxygen gas and nitrogen gas is about 2.
11. The method of claim 10, wherein the partial pressure of nitrogen in the chamber is at least equal to 8: 1 and at least equal to the partial pressure of argon therein. 12. The method of claim 11, wherein the nitrogen-containing iridium oxide film contains about 2-20 atomic% nitrogen. 13. The method of claim 11, wherein the substrate and iridium metal target are separated by a distance of about 3-6 inches. 14. The total gas pressure in the chamber during sputtering is in the range of about 5-100 mtorr.
The method described in 1. 15. The method of claim 14, wherein the chamber pressure is in the range of 40-75 mtorr. 16. The method of claim 14, wherein the substrate is selected from the group consisting of glass and organic polymers. 17. The method of claim 14, wherein the surface of the substrate provided in step (a) has a coating of electrically conductive metal oxide film. 18. The method of claim 17, wherein the electrically conductive metal oxide is selected from the group consisting of tin oxide and indium / tin oxide. 19. A) a first transparent substrate having a first layer of an electrically conductive metal oxide film and a second layer of an electrochromic film on its surface; b) an electrically conductive metal oxide on its surface. Film first
A second transparent substrate having a layer and a second layer of electrochromically active nitrogen-containing iridium oxide film; c) provided between and in contact with the electrochromic film and the iridium oxide film. An electrochromic article having an ion conductive layer; 20. The first and second transparent substrates are selected from the group consisting of glass and organic polymers.
Item 9. 21. The article of claim 19, wherein the electrically conductive metal oxide film is selected from the group consisting of fluorine-doped tin oxide and tin-doped indium oxide. 22. The article of claim 19, wherein the electrochromic film is selected from tungsten oxide and compounds of tungsten oxide. 23. The iridium oxide film is 4
20. The article of claim 19 containing .about.12 atomic% nitrogen. 24. The iridium oxide film is 1
20. The article of claim 19 containing 2-18 atomic% nitrogen. 25. The electrically conductive metal oxide film is tin-doped iridium oxide, the electrochromic film is tungsten oxide, and the iridium oxide film contains 4-18 atomic% nitrogen. The listed supplies. 26. The article of claim 25, wherein the transparent substrate is selected from the group consisting of glass and organic polymers. 27. The transparent substrate is an organic polymer,
27. The article of claim 26, wherein an adhesion improving organic polymer primer is provided between the respective interfaces of the surface of the electrically conductive metal oxide film and the transparent substrate.