JPS5994744A - Whole solid-state electrochromic display element - Google Patents

Abstract

PURPOSE:To obtain the titled element hardly causing short circuit between electrodes by forming an electrically insulating film specified in thickness on a transparent electrode formed on a substrate. CONSTITUTION:The first <=50nm thick insulating layer 6 is deposited on a desirably patterned transparent electrode 2 formed on substrate 1. This layer 6 is coated with a photoresist 7 and exposed to form a photoresist layer 7 patterned only on the part in which an electrochromic layer is to be deposited. After the second >=50nm thick insulating 8 has been formed on the whole surface of the substrate 1, the photoresist layer 7 is removed, resulting in leaving the <=50nm thick insulating layer 6 in the part to be occupied by the electrochromic layer and the >=50nm thick insulating layer in the part not to be occupied by said layer. Then, at least one of the electrochromic layer 3 and at least one of a solid electrolyte layer 4 are laminated on said substrate 1, and an opposite electrode 5 is formed on the layer 4.

Description

[Detailed description of the invention] [Technical field to which the invention pertains] This invention relates to an all-solid-state electrochromic display element.

[Prior art and its problems]

Drowsiness color display elements using transition metal oxides such as WOs have been attracting attention because of their excellent visibility.

In the all-solid-state electrochromic display element, since a one-body turtle electrolyte is used in the in:M quality, the structure of the element is simpler than that using an fn liquid turtle electrolyte, and there are no problems with the glaze. It has advantages. All-solid-state electrochromic display elements generally have the structure shown in FIG.

That is, a transparent electrode (2) formed on a glass substrate (1)
) is laminated with a drowsy coloring layer (3) made of a transition metal oxide. A solid electrolyte layer (4) such as 5ift eMyF or *NjOssiO is laminated thereon, and an opposing layer (5) is provided.

Although the all-solid-state electrochromic display element is extremely easy to form as described above, the inventors have conducted experiments and found that there are some problems as described below. That is, since the transparent electrode and the opposing polarization are laminated with a layer of 1.sulfide or fluoride having a thickness of at most 1 μm separated, a short circuit between the electrodes is likely to occur. K! If a short circuit occurs between them, no electric field will be applied to the electrochromic layer and the solid electrolyte layer, and ion injection into the electrochromic layer will not occur, resulting in a defective product that does not develop drowsy coloring.

The cause of 0 short circuits between electrodes is usually attributed to the glaze coloring layer, solid electrolyte layer, and cracks in the bottle holes. Therefore, in order to prevent short circuits, it is considered effective to reduce the dust in the work room that causes pinholes, and specifically, to work in a clean room. It is necessary to form a colored solid electrolyte layer densely.

However, these measures have the following problems. First of all, clean room work requires a large number of personnel to maintain the equipment, and in order to keep the equipment fully functional, maintenance and management of the equipment requires a lot of effort and expense, and above all, work efficiency is reduced. The coloring principle of the MFC drowsiness color display element is based on the diffusion of ions between the electrochromic layer and the solid electrolyte layer, so the dense formation of the electrochromic layer and the solid acid electrolyte layer itself This inhibits the diffusion of ions in the thin film, resulting in deterioration of the ia electrochromic properties, that is, a decrease in display contrast and a decrease in response speed.

Therefore, the problem of VIL short circuit has been an extremely important constraint in the production of all-solid-state ECDs. Furthermore, in an actual device that displays character stamps, the transparent part on which the electrochromic layer is not formed occupies a large area, but the transparent part on which the electrochromic layer is not formed also occupies a large area. Since it is opposite to l(-.

Defects generated in the solid solute layer directly lead to short circuits and impede the operation of the device. As described above, the thin film laminated type all-solid-state electroluminescent element is easy to form and has a thin element thickness, and although it is an extremely promising element, it has been very difficult to actually manufacture it.

[Purpose of the invention]

The present invention has been made to solve the drawbacks or problems of the all-solid-state drowsiness coloring element described above, and it is an object of the present invention to provide an all-solid-state drowsiness coloring element having a structure in which short circuits between electrodes are less likely to occur.

[Summary of the invention]

The all-solid drowsiness coloring element of the present invention contains 1. An insulating layer that is easy to form a dense film is laminated on the transparent electrode on which the electrochromic layer is laminated with a thickness of 500X or less (hereinafter referred to as the first short-circuit prevention layer), and the drowsy coloring IL is laminated. A second short-circuit prevention layer with a thickness of 500 A or more and less than C is provided between the feed electrode and the opposing fli electrode on the transparent electrode that is not exposed.
This prevents short circuits between TFIs.

The electrical insulator of the present invention may be composed of a single film having different film thicknesses, or may be composed of a plurality of films as shown in FIGS. 3 to 5. In general, it is easier to fabricate one film if it is formed from multiple films. transparent uA
It is presumed that providing a short-circuit prevention layer between the Hikita and the counter electrode inhibits ion exchange between the Shikiiromura layer and the solid electrolyte and deteriorates the electrochromic properties. By using a material with a thin prevention layer and high contact rate,
Contrary to predictions, it has virtually no effect on electrochromic properties in practice.

[Embodiments of the invention]

Hereinafter, the present invention will be described in detail based on Examples.

Example 1 FIG. 2 is a diagram showing the manufacturing process of the all-solid drowsiness coloring element of the present invention, and will be explained using the drawings. A first short-circuit prevention layer (1) is formed on a glass substrate (1) and patterned into a desired pattern on a transparent electrode (2) using a sputtering method.
6) is deposited on the entire surface with a film thickness of 500λ or less (FIG. 2B). Next, a photoresist (
7) is coated and exposed to light, and the photoresist In (7) is left on only the portion where the transparent-extreme coloring layer is to be deposited (FIG. 2C). (An 8132 short-circuit prevention layer (8) is formed on the entire surface of the substrate to have a thickness of 500^ or more using a sputtering method. Then.

When the resist is removed (so-called lift-off process), the second
The part where the electrochromic layer is formed on the transparent electrode as shown in the figure.
A substrate is obtained in which a glossy edge 111 with a thickness of 1500 Å or less is formed, but an insulating film with a thickness of 500 Å or more is formed in the areas where it is not formed. For example, an electrochromic layer such as WOs is formed on such a substrate by a mask evaporation method or a photoetching method, and then a solid consisting of ZrO, Lf, IVC, and gold (Au) is deposited on the substrate. ) The electroluminescent element according to the present invention can be obtained by vapor-depositing or sputtering opposing electrodes. It is shown in cross section in FIG. Table 1 shows the characteristics of the all-solid-state electrochromic display element thus obtained.

As a comparative example, the 911-η properties of a conventional four-color display element without the first and second short-circuit prevention layers were compared. Providing a short-circuit prevention layer as shown in the table makes it possible to significantly reduce short-circuits between electrodes.

In this example in which the first and second short-circuit prevention layers are provided between the drowsiness coloring layer and the solid electrolyte J-, if the thickness of the first short-circuit prevention layer is particularly large, the drowsiness color Il! ! , deteriorating the characteristics. This &-i, the first short circuit prevention JV is the ion diffusion path 1i
This is considered to be the result of inhibiting lI.

The dielectric constant of the first short-circuit prevention layer shown in Table 1 is a value at a frequency of IR4Hz of a 5000A thin film formed by sputtering. In all samples, the short-circuit prevention effect is clearly recognized. As can be seen from the table, it can be seen that the higher the dielectric constant of the first short-circuit prevention layer and the lower the dielectric constant of the second short-circuit prevention layer, the less influence it has on the electrochromic properties. Koru
This is because the drowsiness capacity l of the short-circuit prevention layer becomes large and can absorb the current caused by the ion spear 9 between the drowsiness coloring layer and the electrolyte layer due to the polarized charge. On the other hand, if the dielectric constant of the second short-circuit prevention layer is large, the blocking capacity of the element itself becomes large, and the coloring/fading speed decreases.

Example 2 In the above-mentioned example, the first short-circuit prevention layer was provided on the entire surface of the transparent electrode, but the first short-circuit prevention layer was subjected to a battening process to form the structure shown cross-sectionally in FIG. 4, that is, an electrochromic layer. It can also be provided only in the part where it is laminated. Although the slamming process increases, this is the most preferable in terms of drunkenness.

Further, as shown in FIG. 5, it is also possible to form the first short circuit prevention layer after first forming the second short circuit prevention layer JvJ.

As explained in the examples above, the all-solid-state drowsiness color display element according to the present invention is easy to form and has a high manufacturing yield (which can be said to have great practical advantages).

〔Effect of the invention〕

According to the present invention, since the short-circuit prevention layer made of a dense and uniform thin film insulates the transparent electrode and the counter electrode, an element is obtained in which electrode short-circuits are less likely to occur.

Varnish thousand years white

[Brief explanation of drawings]

FIG. 1 is a schematic cross-sectional view of an all-solid-state electrochromic display element according to the present invention, showing a conventional example of an all-solid-state electrochromic display element. (1)...Glass substrate, (2)...Transparent electrode, (3
)...Drowsy coloring layer, (4)...Solid electrolyte, (5)
... Counter electrode, (6) ... First short circuit prevention layer, (7)
... Photoresist button, (8) ... Second short circuit prevention layer. Representative Patent Attorney Kensuke Chika (and 1 other person) Figure 1 <C) (/ri/ Figure 8 Figure 4 Figure 511

Claims (1)

[Claims] In an all-solid-state drowsiness coloring display element, which is formed by stacking at least one drowsiness coloring layer and at least one solid electrolyte layer on a substrate with a transparent electrode stamped into a predetermined shape, and then providing a counter electrode, An electrically insulating film having a film thickness of 500X or less in the part where the finest electrochromic layer is laminated and a film thickness of 500X or more in the part where the electrochromic layer is not laminated is the transparent! An all-solid-state electrochromic display element characterized by being formed with the highest quality.