JPS62129823A - Production of fully solid state electrochromic element - Google Patents

Abstract

PURPOSE:To produce an excellent electrochromic element by impressing a voltage which is below the breakdown voltage of the element and controlled to obviate the generation of a coloring and decoloring reaction between both color forming layers and ion donative layers between counter electrodes after lamination thereby burning down the leak part in the element. CONSTITUTION:The inside of a vacuum vessel is maintained in a dry atmosphere. Respective lead wires 8, 9 are so connected to terminals 34, 35 of a voltage impressing device 33 that an upper transparent electrode 7 side is positive pole and a lower transparent electrode 3 is a negative pole under an atm. pressure. The initial impressed voltage is impressed between the electrodes 3 and 7 and the same operation is repeated until the final impressed voltage attains a prescribed value by stepwise increasing the impressed voltage. Eddy current flows between the electrodes 3 and 7 when the leak part exists in the element but the leak part is heated and melted by the Joule heat generated by the impressed voltage; therefore, the leak part is quickly burnt down. The voltage is so controlled as to obviate the generation of the coloring and decoloring reaction during the voltage impression. The voltage impression is quickly executed to avoid the generation of the transfer of ions in the element.

Description

[Detailed Description of the Invention] Object of the Invention (Field of Industrial Application) The present invention relates to a method for manufacturing an all-solid-state electrochromic device, and more specifically, a modification treatment for improving the characteristics of an all-solid-state electrochromic device. It is about law.

(Prior art) Electrochromic device (hereinafter abbreviated as ECD)
is an element whose color and light transmittance change reversibly by inducing a redox reaction in the electrochromic substance inside the element when voltage is applied from the outside, and is used in LEDs (light emitting diodes) and LCDs (liquid crystals). Practical applications are progressing as devices with unique features.

Various types of ECDs have been developed, but all-solid-state ECDs, in which all the layers constituting the device are made of solid materials, are excellent devices in terms of reliability, cost, and versatility. It is.

In addition, the above-mentioned all-solid-state BCD can be manufactured using various physical vapor deposition (PVD) methods, such as vacuum evaporation, sputtering, a combination of these two methods, or an ion-build method developed by the present inventors. A method that combines the rating method and the electron beam (EB) i deposition method has been adopted.

(Problem to be solved by the invention) However, during the above manufacturing process, impurities in the atmosphere or in the device mix into the device, causing pinholes and forming a partial leak between the opposing electrodes. This has become a problem.

Particularly in the case of a method that combines a vacuum evaporation method and a sputtering method, it is necessary to move the element from one device to another each time, so there is a high possibility that impurities in the atmosphere will be mixed in.

Furthermore, since each layer of the device is composed of an extremely thin porous film, both electrodes may partially leak, which causes deterioration of the device's performance characteristics.

Structure of the Invention (Means for Solving the Problems) In order to solve the above problems, the present invention provides an oxidized coloring layer between a pair of opposing electrodes, one of which is a transparent electrode,
In a method for producing an all-solid-state ECD comprising laminating an ion donor layer and a reductive coloring layer, the recoloring layer and ion donor An all-solid-state type E characterized in that the leakage portion in the element is burnt out by applying a voltage controlled so that no coloring/decoloring reaction occurs between the body layers.
This method adopts the CD manufacturing method.

(Function) The all-solid-state ECDO coloring/decoloring reaction occurs due to the reversible movement of ions between the oxidation coloring layer, the ion donor layer, and the reduction coloring layer. It is presumed that the water content is involved.

Therefore, a controlled voltage is gradually applied so that the coloring/decoloring reaction does not occur between the opposing electrodes of the ECD after lamination, that is, the movement of ions does not occur due to the electrochemical reaction between moisture and each of the layers. By applying this voltage, only electron movement occurs inside the element.

Then, the leak portion generates heat and melts due to Joule heat caused by the movement of electrons, and thus the leak portion is burned out.

(Example) An example embodying the method of the present invention will be described below with reference to FIGS. 1 to 3.

The ECD1 manufactured in this example is a cellular all-solid-state ECD, and as shown in FIG.
It is formed on a substrate 2 made of a 60 x 1 n+ soda lime glass plate with an interelectrode area of 50 x 50 x 1.

The specific structure is that ITO (5% by weight S) is applied to the upper surface of the substrate 2.
The film thickness is approximately 200 mm.
A lower transparent electrode 3 is formed on the upper surface of the lower transparent electrode 3, and an oxidation coloring layer 4 made of NiO (about 6000 thick) and an ion donor layer 4 made of Ta205 about 5000 thick are formed on the upper surface of the lower transparent electrode 3. 5, and a reduction coloring layer 6 made of WO3 and having a thickness of about 6000m are sequentially laminated.Furthermore, an upper transparent electrode 7 made of ITO and having a thickness of about 2000m is formed on the upper surface of the reduction coloring layer 6. Furthermore, lead wires 8.9 are connected to the ends of the lower transparent electrode 3 and the lower transparent electrode 7, respectively.

Next, a method of manufacturing the ECD 1 having the above structure will be explained.

First, regarding the configuration of the apparatus A used in this manufacturing method, the ECD 1 is manufactured in a vacuum chamber 21 as shown in FIG.

At the bottom center of the vacuum chamber 21, each layer 3.4.
A crucible 23 is installed for placing tablets of raw materials 5.6 and 7. Also, below the crucible 23 is an E
An EB gun 25 connected to the B electric fi 24 is installed, and a high frequency coil 27 connected to a high frequency power source 26 is installed above the crucible 23. And the above EB gun 23
The tablet vapor evaporated by the high frequency coil 27
It is designed to be ionized by

Furthermore, a holder 28 for supporting the substrate 2 is installed above the vacuum chamber 21, and a heater 28 for heating the substrate 2 is installed above the holder 28.

Hereinafter, a method for producing ECD1 using apparatus A having the above configuration will be explained step by step.

(1) Cleaning of the substrate 2 First, the substrate 2 was ultrasonically cleaned in a neutral detergent solution, rinsed with distilled water, and further air-dried in a clean atmosphere.

(2) Formation of Lower Transparent Electrode 3 As shown in FIG. 2, the substrate 2 was placed in a holder 28 and preheated to about 200° C. by a heater 29. Further, after reducing the pressure inside the vacuum chamber 21 to 1X10 Torr, argon gas and oxygen gas were supplied to adjust the pressure to 5X10 Torr.

Next, the ITO tablet in the crucible 23 is inserted into the EB gun 25.
The lower transparent electrode 3 was formed by heating and evaporating the vapor by an electron beam emitted from the substrate, and ionizing the vapor by a high-frequency coil 27 to deposit it on the substrate 2.

(3) Formation of oxidized coloring layer 4 The temperature of the substrate 2 is kept at 200°C, and only argon gas is supplied into the vacuum chamber 21.
The atmosphere was created.

Next, the NiO tablet in the crucible 23 was heated and evaporated by an electron beam emitted from the gun 25 in an EB, and the vapor was deposited on the lower transparent electrode 3 to form the oxidized coloring layer 4.

(4) Formation of ion donor N5 The substrate 2 is heated to about 300° C., and argon gas and oxygen gas are supplied into the vacuum chamber 21 for 5×10T.

Created a rr atmosphere.

Next, the Taz05 tablet in the crucible 23 was heated and evaporated by an electron beam emitted from the EB gun 25, and the vapor was ionized by the high frequency coil 27, thereby forming the ion donor layer 5 on the oxidized coloring layer 4.

(5) Formation of reduction coloring layer 6 The temperature of the substrate 2 is set to about 200°C, and argon gas (or nitrogen gas) is supplied into the vacuum chamber 21.
Created an atmosphere of rr.

Next, the WO3 tablet in the crucible 23 is placed in the EB gun 25.
It was heated and evaporated by an electron beam emitted from the ion donor layer 5, and the vapor was deposited on the ion donor layer 5 to form a reduction coloring layer 6.

(6) Formation of Upper Transparent Electrode 7 The upper transparent electrode 7 was formed on the reduction coloring layer 6 by the same method as for forming the lower transparent electrode 3 above.

(7) Attaching the lead wires: After the above lamination process was completed, the ECD 1 was taken out of the vacuum chamber 21, and the lead wires 8.9 were bonded to each of the electrodes 3.7.

(8) Modification treatment By applying a predetermined DC voltage (1 to several ■) between both electrodes 3.7 of the ECD 1 obtained as above,
A coloring/decoloring reaction occurs between both full color layers 4.6. However,
As described above, during the above manufacturing process, impurities in the atmosphere or in the device may enter the device, resulting in pinholes, and a leakage portion may be formed partially between the electrodes 3 and 7.

Further, since each layer of the element is composed of an extremely thin porous film, a leakage portion may be partially formed between the electrodes 3.7. Therefore, the leakage portion caused by the above cause was removed in the following manner.

That is, the inside of the vacuum chamber 21 is made into a dry atmosphere, and each lead wire 8. 9
was connected to terminals 34 and 35 of voltage application device 33.

Then, as shown in Fig. 3, a voltage was applied between the two electrodes 3.7 for 3 seconds at an initial applied voltage of 5 µ, and then the applied voltage was increased stepwise until the final applied voltage reached 100 µ. The same operation was repeated. At this time, if there is a leakage part in the element, an overcurrent will flow between the two electrodes 3.7.
The leak portion generates heat and melts due to the Joule heat generated by the applied voltage, so that the leak portion is quickly burnt out. The peak current at each stage indicates that a leakage portion exists in the element and that the leakage portion is burned out due to heat generation due to the applied voltage.

In order to burn out the leakage part, a higher applied voltage is required than when causing the coloring/decoloring reaction.
It is necessary to perform this while controlling the voltage so that coloring/decoloring reactions do not occur. That is, it is necessary to perform the process in a short time so that ion movement does not occur within the device.

Since it is presumed that water is involved in the coloring/decoloring reaction, it is desirable to carry out the above operation in a dry atmosphere. That is, the less water in the element, the less likely the coloring/decoloring reaction will occur, so that a sufficient voltage can be applied to the leakage portion, and as a result, the leakage portion can be burned out in a short time. Therefore, when performing the above operation in the atmosphere, it is necessary to repeatedly apply a pulse voltage, and it takes a long time to burn out the leakage portion.

In addition, the breakdown voltage of all-solid-state ECD is 5 M V/c
Since the voltage is about m, it is necessary to apply a voltage below this value.

It should be noted that the present invention is not limited to the configuration of the above-mentioned embodiment, but can also be embodied as follows, for example.

(2) In addition to soda glass, resin glasses such as polymethyl methacrylate and polycarbonate may be used as the ECD substrate, and the elements may be laminated at a temperature below the deformation temperature.

■ T + Oz, Sn 02, as electrode constituent materials
Au, Ag, Pt, etc. may also be used.

■ N' (OH)x as a constituent of the oxidized coloring layer
, Cr2O2,I r (OH),, T ro,
, Rh0%, Rh(0)()X, Ru(OH)
, etc. may be adopted.

■ LiF 5t02 as ion donor layer constituent material
, Z r 02, Crzo3, MgF2, Ca FZ,
Al2O3, Y2O3, Na-β-alumina, L 13
N (L') or the like may be adopted.

■ Y0O3, V2O, Nb as reduced coloring layer constituents
2O, etc. may be adopted.

■ Other ion blating methods, sputtering methods,
The element may be formed using a vacuum evaporation method or the like.

Effects of the Invention As detailed above, the method of the present invention burns out the leakage portion of the electrochromic device by applying a voltage between both electrodes of the device that is controlled so that no redox reaction occurs in the device. Therefore, it exhibits an excellent effect of improving the characteristics of the device, and is an extremely useful means as a method for manufacturing an electrochromic device, especially as a method for modifying the device.

[Brief explanation of drawings]

Figure 1 is a cross-sectional view showing the modification process of all-solid-state ECD;
FIG. 2 is a cross-sectional view showing the lamination process of the ECD, and FIG. 3 is a diagram showing the relationship between voltage application to the ECD and interelectrode current over time. 1. Electrochromic device (ECD), 2. Substrate, 3. Lower transparent electrode, 4. Oxidation coloring layer, 5. Ion donor layer, 6. Reduction coloring layer, 7. Upper transparent electrode. , 33...voltage application device.

Claims (1)

[Claims] 1. An oxidation coloring layer (4), an ion donor layer (5) and a reduction coloring layer (6) are provided between a pair of opposing electrodes (3, 7), at least one of which is a transparent electrode. In the production of an all-solid-state electrochromic device formed by stacking, there is a layer between the opposing electrodes (3, 7) that has a breakdown voltage equal to or lower than the breakdown voltage of the device, and that both the coloring layers (4, 6) and Manufacture of an all-solid-state electrochromic device characterized in that leakage portions in the device are burnt out by applying a voltage controlled so that no coloring/decoloring reaction occurs between the ion donor layer (5). Method. 2. The applied voltage is a DC voltage, and the electrode (3) on the side of the oxidized coloring layer (4) is a negative pole, and the reduced coloring layer (
6. The method for manufacturing an all-solid-state electrochromic device according to claim 1, wherein the electrode (7) on the side (6) is a positive electrode. 3. The method for manufacturing an all-solid-state electrochromic device according to claim 1, wherein the voltage is applied in a dry atmosphere.