JPH06136551A - Gold single crystal thin film and its production and application therefor - Google Patents

Abstract

PURPOSE:To produce the gold single crystal thin film usable for the comb-shaped electrodes of a surface acoustic wave element having excellent mechanical migration resistance and oxidation deterioration resistance, a curved crystal for X-ray spectroscopy having an excellent wavelength resolving power and light condensing performance, an adhesive element by the stress relieving of the common electrode of a liquid crystal panel and the coagulation effect utilizing the superplane of the gold thin film, etc. CONSTITUTION:The gold complex in a gold complex soln. is subjected to a decomposition treatment, by which the gold in the soln. is changed into a supersatd. state. A substrate 1 is brought into contact with this soln. to form the nucleus of the gold on the surface of the substrate 1 and the gold thin film consisting of the gold single crystal or gold single crystal group is grown by self-matching on the surface of the substrate on the basis of such nucleus, by which the gold single crystal thin film 3 is obtd.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a device or element useful for various electronic techniques, in particular, a surface acoustic wave element, a polycrystal type X-ray spectroscopic curved crystal for simultaneously focusing or focusing X-rays, TECHNICAL FIELD The present invention relates to an electrode for a liquid crystal optical panel and an adhesive element for adhering by a cohesive action using a hyperplane of a gold thin film, a thin film made of a gold single crystal or a gold single crystal group used therefor, and a manufacturing method thereof.

[0002]

2. Description of the Related Art First, a prior art relating to a first invention, a surface acoustic wave element, will be described.

A surface acoustic wave device for generating and receiving a surface acoustic wave by at least one comb-shaped electrode (IDT) provided on a piezoelectric substrate has been actively researched in recent years and widely applied to filters, resonators, convolvers and the like. Has been done. Further, when a high frequency electric signal is input to the comb-shaped electrode (IDT) provided on the piezoelectric substrate, electro-mechanical conversion occurs due to the piezoelectric effect of the piezoelectric substrate, surface acoustic waves are generated, and propagate on the piezoelectric substrate. It has been known. These comb-shaped electrodes (IDT) are made of a conductive material such as Al and Au, and are usually formed by using a photolithography technique.

FIG. 19 is a schematic view showing such a conventional surface acoustic wave element. FIG. 19A is a plan view and FIG. 19B is a sectional view taken along the line AA 'in FIG. In the figure, 1 is lithium niobate (LiNb ₃ ), lithium tantalate (Li
A piezoelectric substrate such as TaO ₃ ) or quartz (SiO ₂ ), and 6 is a comb-shaped electrode formed on the surface of the piezoelectric substrate 1.

However, in the surface acoustic wave device of the above example, since the comb-shaped electrode is mainly made of polycrystalline Al formed by a vapor deposition method, a sputtering method, or the like, mechanical stress is caused by the surface acoustic wave stress. There is a problem of electrode deterioration such as occurrence of migration and breaking of comb-shaped electrode fingers.

It is considered that this mechanical migration is caused by polycrystalline metal atoms diffusing at grain boundaries due to surface acoustic wave stress.

Since the surface acoustic wave stress applied to the comb-shaped electrode increases as the power and frequency increase, the electrode surface is deteriorated in a surface acoustic wave filter for communication and a surface acoustic wave resonator that require high-frequency high power transmission. Becomes even more problematic.

In particular, in the surface acoustic wave device for automobile telephones, which requires power of 1 to 5 W in the 800 MHz band, improvement of the comb-shaped electrode is indispensable.

In order to suppress the electrode deterioration due to such mechanical migration, for example, Al or Cu or Ni is used.
Although a method of suppressing the grain boundary diffusion of metal atoms by adding Al is being studied, there is a problem that further higher durability is required and there are variations and fluctuations in the electrode film composition and an increase in the electrode film resistance. .

Next, a second invention, a prior art relating to a curved crystal for polycrystalline X-ray spectroscopy will be described.

X having a relatively short wavelength of about 1 to 10Å
Lines are widely used for crystal structure evaluation and composition analysis.

For these measurements, it is often necessary to extract only the desired wavelength. In this wavelength range, a filter, a dispersive crystal, a total reflection mirror, etc. have a spectral function. Of these, the filter and the total reflection mirror have a wide wavelength band, and the band is also largely restricted. For this reason, a dispersive crystal is used when a narrow wavelength band is required. Further, the X-ray optical system may be required to have the function of condensing the X-rays or simultaneously focusing the X-rays or forming an X-ray image at the same time. When these are performed in the narrow wavelength band, a curved crystal in which the crystal is curved into a desired shape to have a spectral action and a light focusing action is often used.

When X-rays are focused or imaged only in one-dimensional direction, a cylindrical curved crystal is used. On the other hand, when the X-ray is focused or imaged two-dimensionally, a three-dimensionally curved crystal such as an ellipsoidal surface or a spherical surface is used.

The curved dispersive crystal utilizes plastic deformation or elastic deformation of the crystal material, and therefore has a radius of curvature of 10
If the size is reduced to about cm, the crystal is cracked due to strain during processing. For this reason, the light-collecting performance and the spectral performance are deteriorated, and a uniform X-ray image cannot be obtained when used for imaging. Therefore, it is difficult to manufacture such a crystal having a small radius of curvature, and there is a problem that the device becomes large. Further, it is difficult to deal with a three-dimensional curved surface such as an elliptic surface or a spherical surface.

In order to solve these problems, the crystal has been thinly cut out and attached to a desired curved surface. However, cracks and dislocations in the crystal cannot be prevented, and the resolution is deteriorated due to stress. I will end up.

Furthermore, a method of making incisions in a crystal at a fine pitch and bonding the crystals on a curved substrate having a desired shape has been attempted. However, this processing has a problem that the cutting is very difficult because the cutting pitch is fine and the cutting must be deep.

In addition, there has been proposed a method of growing a single crystal thin film on a desired curved substrate by using a technique of graphoepitaxy or selective nucleation. Graphoepitaxy forms a fine structure on the substrate surface and utilizes the property that the orientation of the crystal nuclei is influenced by the substrate structure to generate polycrystalline nuclei with uniform crystallographic orientations, which are then grown and continuously grown into single crystals. It is to crystallize. In the selective nucleation method, when a region having a high nucleation density is finely provided on the surface of a substrate having a low nucleation density and a film-forming substance is deposited, a single nucleus is formed on a substance having a high nucleation density. Then, a polycrystalline thin film is formed by growing on the surface of the substrate having a low nucleation density.

In the curved dispersive crystal, the crystal lattice plane to be diffracted by X-rays must be curved in a desired shape. Therefore, in the above method, the crystal orientation such that the crystal lattice planes are parallel to each other on the curved substrate of a desired shape is grown.
A polycrystalline or single crystal thin film having a crystal plane along the curved surface of the substrate is formed. At present, a perfect single crystal cannot be obtained even by the graphoepitaxy method, and a mosaic polycrystal is formed. Therefore, each crystal is actually a polycrystal thin film in which each crystal is oriented perpendicular to the substrate surface.

When a polycrystalline thin film is formed on a curved substrate to form a dispersive crystal, the most important issue is the parallelism between the individual crystal planes and the substrate plane. This tolerance is the focal length, image resolution,
Determined by energy resolution, etc. For example, a magnification of 20
Double, in order to obtain an image resolution of 10 μm in an imaging system in which the distance between the crystal plane and the image is 10 cm, the shift angle of the crystal needs to be 10 ⁻³ rad or less. Generally, when a diffraction intensity curve of a single crystal is measured by an X-ray diffraction method, the spread is 10 ^-4 ra.
Although it is about d, the crystallinity of the polycrystalline thin film obtained by the above-mentioned graphoepitaxy has a considerable variation in both the vertical and horizontal orientations with respect to the substrate. In some cases, there is a variation of about 2.5 × 10 ^-2 rad or more. The shift angle of the crystal is larger in the selective nucleus growth. Therefore, it has been a problem that the polycrystalline dispersive crystal produced by these methods cannot obtain sufficient spectral performance, light-collecting performance, and imaging performance.

Further, in the selective nucleus growth method and the like, since the crystal thin film is formed by the CVD method and the substrate temperature is raised to several hundreds of degrees or more, the substrate which is previously formed into a desired shape by polishing or the like is largely deformed. It was also a problem.

Next, the third invention, the prior art relating to the electrodes of the liquid crystal optical panel will be described.

With the progress of electronics technology, especially semiconductor technology, the amount of information that can be handled is increasing at an accelerating rate. Correspondingly, since most of the information exchange between electronic devices and human beings is performed visually, the dependence on displays is increasing more and more.

In order to make the conventional liquid crystal optical panel have higher gradation, higher contrast and higher brightness, or to realize high image quality on a large screen, large-sized panels and a large number of pixels have been actively researched and developed. . In order to satisfy both the large size and the high performance of the panel at the same time, there is an increasing demand for the technical content which has not been considered as a problem in the conventional liquid crystal panel manufacturing technology.

Conventionally, a liquid crystal optical panel is, for example, a TFT-
There is an example of using amorphous Si in an LCD, and FIG. 27 shows its general configuration. In the figure, 213 is amorphous Si, 214 is a gate electrode, 215 is a gate insulating film, 216 is a pixel electrode, 217 is a protective film, 218 is a drain electrode (V _D ), 219 is a source electrode (V _COM ), 2
Reference numeral 20 denotes a black matrix and 221 denotes a color filter. Further, 203 is an alignment film, 204 is a glass substrate, 2
Reference numeral 07 is a common electrode (V _COM ), and 209 is a liquid crystal. The common electrode 207 for the pixel electrode 216 is generally formed as a solid film over the entire surface of the panel as shown in the figure. Usually, ITO or the like is used as an electrode having high transmittance, and also has good conductivity and good transmittance.
A sputtering method is used as a film forming method for satisfying the two conditions.

However, in the conventional structure, since the common electrode is solidly attached by sputtering ITO or the like, there is a problem in that the glass substrate is distorted by stress. Therefore, when forming a liquid crystal panel of 3 inch to 5 inch or more, it is very difficult to form a constant gap between the liquid crystal layer at the center and the edge of the panel, and the liquid crystal internal electric field is equal to the same driving voltage. Since such a phenomenon does not occur, it leads to deterioration of high image quality performance at the edges and deterioration of reliability of the panel, and it is very problematic when performing gradation display with a ferroelectric liquid crystal or the like.

In particular, in the case of a ferroelectric liquid crystal which is characterized by having a high-speed response as compared with a TN (twisted nematic) liquid crystal which has been used as a conventional display element, generally, it is necessary to control the alignment. 1 to 2 gaps
It is extremely thin at μm. On the other hand, upsizing of the liquid crystal panel,
It is inevitable that the uniformity of the gap will be more and more strict as the gradation becomes higher.

Further, the prior art relating to the fourth invention and the adhesive element will be described.

Conventionally, the Japan Institute of Metals (Vol. 46, No. 9,
1982, p.935-943), etc., room temperature pressure bonding (adhesion) is to remove the surface film by ion sputtering in ultra-high vacuum and then bring the adhesion surface gap close to an atomic order distance. It required plastic deformation to produce the siding line. That is, an external load is required at the time of bonding in order to cause plastic deformation.

However, in the above-mentioned conventional example, the joining of metals is mainly performed by melting, diffusing action at high temperature such as welding, diffusion or pressure welding at room temperature, or while plastically deforming by applying a load at room temperature. Each of them has the following drawbacks because it must be performed by the action of bringing the bonding surface gap closer to an atomic order distance. (1) Since it is performed at a high temperature, it is difficult to bond materials having a large difference in melting point. (2) Since the diffusion is carried out at a high temperature, the bonding time becomes long, which makes it easy to generate an intermetallic compound at the bonding interface. (3) In the case of adhesion at room temperature, application of an external load causes plastic deformation of the adhesive material, and therefore a large external load needs to be applied during the adhesion.

[0030]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a gold single crystal thin film which can solve the above problems. The present invention also provides various uses of this gold single crystal thin film.

[0031]

Means for Solving the Problems As a result of intensive studies for solving the above-mentioned problems, the present inventors have found that the gold complex in a gold complex solution is decomposed and the gold in the solution is brought into a supersaturated state. The inventors have found that a gold crystal thin film composed of a single crystal and a group of single crystals can be formed on the surface of a substrate, and have completed the present invention.

[0032]

Here, in order to help understanding of the present invention, the gold complex in the gold complex solution is decomposed to shift the gold in the solution to a supersaturated state and form a gold thin film consisting of a gold single crystal group on the substrate surface. The process of forming will be described.

As an example, a case where a thin film is formed on a LiNbO ₃ substrate by [AuI ₄ ] ⁻ as a gold complex and by a volatilization process as a decomposition treatment means will be described.

First, potassium iodide and iodine are added to distilled water to prepare an iodine aqueous solution, and then gold is added to prepare a gold complex solution containing [AuI ₄ ] ^- . At this time, it is considered that I ₃ ⁻ and K ⁺ are present in the solution in addition to [AuI ₄ ] ⁻ .

Next, after the surface of the LiNbO ₃ substrate is brought into contact with the above solution, the temperature of the solution is raised to 30 to 100 ° C. to accelerate the volatilization of the iodine component. In order to maintain an equilibrium state by volatilizing the iodine component existing in the I ₃ ⁻ state in the solution system,
[AuI _4] ^- degradation by dissociation of the iodine components from, or [AuI _4] ^- degradation by direct volatilization believed to proceed iodine component in the complex present in the form of gold is supersaturated state as a result of .

Although the kind of gold complex and the method of decomposition are different, gold powder for conductive gold paste is deposited in a floating state in the system by utilizing the gold supersaturation phenomenon in the solution due to the decomposition of the gold complex. Techniques for this are disclosed in JP-A-56-38406 and JP-A-55-54509. The inventors of the present invention randomly deposit the gold thus supersaturated in the solution as nuclei on the substrate surface, and after that, the nucleation continues for a while, but when a certain number of nuclei are formed. , The growth of nuclei stopped, the nuclei grew in a self-aligned single crystal, and the growth was continued, and it was found that grain boundaries are formed by the collision of each single crystal.

The gold complex used in the present invention includes [A
uI ₄ ] ⁻ , [AuCl ₄ ] ⁻ , [Au (CN) ₂ ] ⁻ , [A
u (CN) _3] ^- or the like include gold complexes containing.

As a means for decomposing the gold complex in the present invention, a method of volatilizing a component which is likely to volatilize such as an iodine component in the complex by heating to shift gold to a supersaturated state,
Examples thereof include a method of reducing to gold atoms by adding a reducing agent.

The heating temperature is preferably about 30 to 100 ° C.

Examples of the reducing agent include hydroquinone,
Pyrogallol, Pyrocachytene, Guchcine, Metol hydroquinone, Amidole, Metol, Sodium sulfite,
Other than sodium thiosulfate, a substance having a reducing action in a solution is used.

In the present invention, the substrate on which the gold single crystal thin film is to be formed is brought into contact with or immersed in the solution containing the above gold complex, and heating or the addition of the reducing agent is started, whereby the gold single crystal is formed on the substrate. A crystal thin film is formed.
The process of forming this gold single crystal thin film is shown in FIG. First, nuclei are generated on the surface 2 of the substrate 1 (FIG. 1 (A)), and a single crystal grows in a self-aligned manner centering on the nuclei in the surface direction of the substrate (FIG. 1 (B)), and then a single crystal is formed. The crystals collide with each other to form grain boundaries 4 and the crystal growth stops (FIG. 1C). In the obtained thin film of gold single crystal group, randomly grown gold single crystals 3 form grain boundaries 4 as shown in FIG.

In the gold crystal thin film formed by the above method, each crystal is a single crystal having no defect, and has a 111 orientation in the direction perpendicular to the substrate. The crystal surface is extremely smooth.

The crystal orientation, which is important when used as a dispersive crystal, is extremely high and is slightly inferior to that of a Si single crystal. When the diffraction intensity curve is measured by the X-ray diffraction method, the angular spread of the diffraction peak is almost 10 ^-3 ra.
It is less than d and never exceeds 10 ^-2 rad. Therefore,
If the gold crystal thin film described above is formed as an X-ray diffraction layer on a curved substrate having a desired shape and used as a curved crystal for X-ray spectroscopy, it is possible to create a curved crystal with a small radius of curvature. Compared to the case where the X-ray diffraction layer is formed by the selective nucleus growth method, the spectral performance and the light collection performance are high, and when used for imaging, high image resolution and a uniform image can be obtained. Further, since the surface is extremely smooth, not only the secondary processing of the surface is unnecessary, but also scattered light can be extremely reduced.

Further, the present method is characterized in that the crystal thin film can be formed at almost room temperature and normal pressure, so that the deformation of the substrate after film formation is extremely small and the substrate shape can be maintained.

[0045]

EXAMPLES The present invention will be described in detail with reference to the following examples, but the present invention is not limited to these examples.

Example 1 By using Ti as a surface made of a material having a high nucleation density, LiNbO ₃ as a surface having a low nucleation density, [AuI ₄ ] ⁻ as a gold complex, and volatilization as a decomposition treatment means. An example of producing a comb electrode for a surface acoustic wave element will be described.

First, after Ti is vapor-deposited on the entire surface of the LiNbO ₃ wafer 1, etching is carried out using a resist.
As shown in FIGS. 3 (a) and 3 (b), _{3 is formed} on the LiNbO ₃ wafer.
A substrate was obtained in which the Ti thin film 2 having a size of 3 μm square was formed substantially in the center of the comb-shaped electrode formation region.

In the present invention, by making the surface made of a material having a high nucleation density a sufficiently small area, it is possible to generate nuclei of only a single nucleus, and the size thereof is preferably 10 μm or less, more preferably 5 μm
It is the following.

Next, potassium iodide and iodine are added to distilled water to form an aqueous iodine solution, and then gold is added and dissolved by stirring to prepare a gold complex solution containing [AuI ₄ ] ^- . At this time, in addition to the gold complex [AuI ₄ ] ^- , I
₃ ^- is considered that K ⁺ is present.

The iodine aqueous solution can also be prepared by dissolving an iodide compound other than potassium iodide, such as ammonium iodide. Further, an iodine alcohol solution using alcohol as a solvent or an iodine alcohol aqueous solution using a mixture of alcohol and water as a solvent can also be used in the present invention. The concentrations of iodine, iodide compound in the solution define the amount of gold that can be dissolved.

Next, after the surface of the above-mentioned substrate is brought into contact with the solution, the temperature of the solution is raised to 30 to 100 ° C. to accelerate the volatilization of the iodine component.

[0052] In the solution-based, I ₃ ^- for the maintenance of the equilibrium state of the solution system caused by volatilization of iodine component which is present in the state,
[AuI _4] ^- degradation by dissociation of the iodine components from, or [AuI _4] ^- degradation by direct volatilization believed to proceed iodine component in the complex present in the form of gold is supersaturated state as a result of . The gold 3 supersaturated in the solution is deposited as a single nucleus only on the surface of the Ti thin film 2 having a high nucleation density. At this time, LiNbO having a low nucleation density
₃ Nucleation was not observed on the wafer surface 5 (Fig. 4).
(A), (b)).

As a result of analysis, the formed crystal was a single crystal having no defect and had a 111 orientation. Moreover, as a result of observing the growth rate, the vertical direction: the horizontal direction is 1: 1.
It was found that it was growing at a rate of 00 to 200.

When the growth is further continued, the grain size is about 100.
A gold crystal thin film of 0 μm single crystal was formed (FIG. 5).
(A), (b)).

As described above, the gold single crystal thin film according to the present invention is
The formation position (crystal position and grain boundary position) can be determined by design.

This example shows the effect that a gold single crystal having an extremely smooth surface can be formed. It is considered that this is because the iodine ions present in the solution suppress the generation of new nuclei on the growing gold crystal due to the gold dissolving action.

Thereafter, a resist pattern 7 having a desired comb-shaped electrode pattern is formed on the gold single crystal thin film by using a normal photolithography technique (FIGS. 6A and 6B), and then by an etching method. Then, the comb-shaped electrode 6 was formed by removing the gold in the portion where the resist pattern was not formed (FIGS. 7A and 7B).

Example 2 Next, an example of producing a comb-shaped electrode using a reducing agent as a decomposition treatment means will be described.

In the same manner as in Example 1, a substrate was obtained in which a 3 × 3 μm square Ti thin film was formed on the LiNbO ₃ wafer in the approximate center of the comb electrode formation region. Then, the substrate was contacted with the same gold complex solution as in Example 1. Next, a hydroquinone aqueous solution as a reducing agent was slowly added dropwise to the gold complex solution to cause crystal growth. Further growth, average particle size 100μ
A single crystal of m could be selectively formed.

After that, the same resist pattern as the desired comb-shaped electrode pattern is formed on the gold single crystal thin film by using a normal photolithography technique, and then the gold of the portion where the resist pattern is not formed is etched by an etching method. By removing, a comb-shaped electrode was formed.

Example 3 In the same manner as in Example 1, Ti was vapor-deposited on the entire surface of the LiNbO ₃ wafer, and then etching was performed using a resist to form the LiNbO ₃ wafer 1 on the LiNbO ₃ wafer 1 as shown in FIGS. 8 (a) and 8 (b). Three
A substrate having a 3 μm square Ti thin film 2 formed in a matrix with a feeling of 100 μm was obtained.

The interval between nucleation surfaces is such that nucleation on a material having a low nucleation density is suppressed so that nuclei are not formed by long-range order, that is, the average grain size when a thin film is formed on the entire surface under the same conditions. The following range is preferable.

Next, gold crystals were deposited in the same manner as in Example 1. The gold supersaturated in the solution is deposited as a single nucleus only on the surface of the Ti thin film 2 having a high nucleation density, and no nucleation is observed on the surface 5 made of a material having a low nucleation density. (FIGS. 9 (a) and 9 (b)).

When the crystal growth is further continued, the crystals collide with each other and a grain boundary is formed almost in the middle of each surface made of a material having a high nucleation density, and many surfaces made of a material having a low nucleation density are formed. As shown in FIGS. 10A and 10B, the gold crystal thin film 3 composed of a single crystal group having a grain size of about 50 μm could be formed in the comb-shaped electrode forming region.

As described above, the formation position (crystal position and grain boundary position) of the gold single crystal of the present invention can be known by design.

Thereafter, as shown in FIGS. 11A and 11B, a resist pattern same as a desired comb-shaped electrode pattern is formed on the gold single crystal thin film by using a normal photolithography technique, and then an etching method is performed. Then, the comb-shaped electrode was formed by removing the gold in the portion where the resist pattern was not formed (FIGS. 12A and 12B).

Example 4 First, a negative resist pattern of a comb-shaped electrode was formed on a LiNbO ₃ wafer by using a normal photolithography technique (FIGS. 13A and 13B). Next, potassium iodide and iodine are added to distilled water to form an aqueous iodine solution, and then gold is added and dissolved by stirring to prepare a gold complex solution containing [AuI ₄ ] ^- . Then, after the surface of the above-mentioned substrate is brought into contact with the solution, the temperature of the solution is raised to 30 to 100 ° C to promote volatilization of the iodine component. Gold supersaturated in the solution is deposited as random nuclei on the LiNbO ₃ substrate and the resist. At this time, the nuclei grow in a self-aligned manner while the nucleation density is low.

When the growth is further continued, the crystals collide with each other,
Grain boundaries are formed. Further, on the LiNbO ₃ substrate, the crystals colliding with the resist stopped growing, covered the comb-shaped electrode pattern region surface on the substrate, and a gold crystal thin film pattern consisting of a single crystal group with a grain size of about 50 μm was formed (Fig. 14 (a),
(B)). Then, the resist and the gold thin film on the resist were removed to obtain a comb-shaped electrode (FIGS. 15A and 15B).

Example 5 As a fifth embodiment, an example in which a comb-shaped electrode is manufactured by using a resist as a surface made of a material having a high nucleation density and a surface made of Cr and a surface made of a material having a low nucleation density. Will be described.

After the Cr surface 2 was vapor-deposited in the comb-shaped electrode forming region on the LiNbO ₃ wafer, the negative resist pattern 7 of the comb-shaped electrode was formed (FIGS. 16A and 16B).

Then, gold crystals were deposited in the same manner as in Example 1, so that the gold single crystal group 3 became LiN as shown in FIG.
The area where the resist pattern was not formed on the bO ₃ substrate was filled up. Then, the resist and Cr were removed to obtain the comb-shaped electrode 6 (FIGS. 18A and 18B).

As described above, by forming Cr between the gold thin film and the LiNbO ₃ substrate, the adhesion of the gold thin film can be improved.

In the present invention, the surface made of a material having a low nucleation density and the surface made of a material having a high nucleation density are not limited, and as a result, there is a relative difference in nucleation density and It is sufficient that the material having a high formation density has a sufficiently fine surface so that a single nucleus is formed.

The maximum distance when the surface made of a material having a low nucleation density and the surface made of a material having a high nucleation density are arranged on the entire surface under the same conditions on the surface made of a material having a low nucleation density. It is preferably within the average particle size.
In other words, in order to increase the maximum arrangement interval, LiNbO ₃ and LiTa having a particularly low nucleation density are used.
It is preferable to use an insulating material such as O ₃ , SiO ₂ , Al ₂ O ₃ .

As a material having a high nucleation density, Au,
Ti, Cr, Cu, W, WSi, MoSi, Fe, S
Conductive and semiconductor materials such as i and Ge can be used.

In the above embodiments, the surface acoustic wave filter is shown as an example of the surface acoustic wave element.
Similar effects can be obtained with an element using a comb-shaped electrode, such as a surface acoustic wave resonator or a surface acoustic wave convolver.

The substrate 1 is not limited to a piezoelectric single crystal such as lithium niobate, but may have a structure in which a piezoelectric film is added on a semiconductor or glass substrate, for example.

Furthermore, by forming the comb-shaped input electrode in the above-mentioned embodiment into a double electrode (split electrode), it is possible to suppress the reflection of the surface acoustic wave at the input electrode and to further improve the characteristics of the device. You can

It goes without saying that the surface acoustic waves excited by the comb-shaped electrodes in the above-described embodiments can be applied not only to Rayleigh waves but also to surface acoustic waves such as Love waves and Sezawa waves that can be transmitted and received by the comb-shaped electrodes.

Example 6 Next, a curved crystal for polycrystalline X-ray spectroscopy will be described.

FIG. 20 is a typical view showing the structure of a polycrystalline X-ray spectroscopy curved crystal 103 according to the present invention. In the figure, 101 is a substrate processed into a curved shape, and
Reference numeral 02 denotes an X-ray diffraction layer of a crystal thin film made of the gold single crystal group formed by this method.

An example of using the curved crystal for X-ray spectroscopy of the present invention in an imaging optical system will be described below.

Substrate 10 is made of silicon carbide whose concave surface is polished to be a part of a spheroid having a major axis of 300 mm and a minor axis of 50 mm.
Used as 1. After mixing 30 ml of hydrochloric acid and 10 ml of nitric acid to prepare aqua regia, 2 g of gold was added to this solution and dissolved by stirring. After dissolution, 10 ml of this solution was taken and placed in a reaction vessel, and 100 ml of distilled water was further added thereto and stirred.
Next, 1 part of sodium hydroxide (NaOH) was added to this solution.
An aqueous solution in which 0 g is dissolved is gradually added.

The surface of the substrate is brought into contact with this solution, and the solution is kept at 40 ° C. After about 1 hour, a gold crystal thin film composed of a gold single crystal group having a grain size of about 100 μm is formed on the substrate. This gold crystal thin film is used as the X-ray diffraction layer 102.
The curved crystal 103 for X-ray spectroscopy is formed.

FIG. 21 shows the structure of an X-ray imaging optical system using the curved crystal 103 for spectroscopy. Reference numeral 104 is an X-ray source, 103 is a curved crystal for spectroscopy, 105 is an X-ray, 106 is a detector, 107 is an object (sample) to be measured, 108 is an object image formed on the detector 106, and 109 is An incident light cutting aperture 110 is a diffracted light cutting aperture. A sample 107 is illuminated by using a copper target X-ray tube as the X-ray source 104. Sample 107 and detector 10
6 are arranged on the focus of the spheroid of the curved crystal 103 for spectroscopy. At this time, the angle of incidence and emission of X-rays on the curved crystal 103 for spectroscopy is 19.09 °. Therefore, the X-ray 105 transmitted and scattered by the sample 107 is reflected and diffracted by the spectroscopic curved crystal 103, and an object image 108 is formed on the detector 106. At this time, X-rays of different wavelengths are emitted from the curved crystal 103 for spectroscopy.
Since the diffraction angles at are different, it is possible to obtain an object image with only X-rays of a desired wavelength by the diffracted light cutting aperture. As the sample 107, a 3 μm mesh pattern formed of gold on a silicon nitride membrane was used.
When an X-ray film is used as the detector 106, the mesh pattern of the sample 107 magnified about 14 times is clearly observed on the X-ray film. From this, the copper Kβ ray and continuous line are separated by the curved crystal for spectroscopy,
It can be seen that a uniform image is formed only by α rays.

Conventionally, a curved crystal having a radius of curvature of about 50 mm is
It is difficult to create a single crystal by elastic or plastic deformation, and sufficient spectral performance and imaging could not be obtained by selective nucleation growth or graphoepitaxy, but the method of the present invention has a small radius of curvature. It was shown that crystals can also be made.

Example 7 Next, an example of using the curved crystal for X-ray spectroscopy of the present invention for spectroscopy and focusing will be described.

The curved crystal used in this example is prepared as follows.

The substrate 101 is obtained by polishing quartz so as to form a concave spherical surface having a radius of 80 mm. Potassium iodide and iodine are added to distilled water to prepare an iodine aqueous solution, and then gold is added and dissolved by stirring to prepare a gold complex solution containing [AuI ₄ ] ^- . Next, after contacting the surface of the substrate 101 with the solution, the temperature of the solution is raised to 70 ° C. to promote volatilization of the iodine component. Gold that was supersaturated in the solution was deposited on the substrate,
A gold crystal thin film 102 made of a gold single crystal group having a grain size of about 400 μm is formed. Each gold single crystal of this gold crystal thin film has a 111 orientation with respect to the substrate. The thickness of the gold crystal thin film is about 3 μm. The gold crystal thin film is used as an X-ray diffraction layer.

FIG. 22 shows the structure of the curved crystal 103 for spectroscopy applied to an electron beam excited X-ray composition analysis method.

An electron gun 111 irradiates the sample 113 with an electron beam 112 generated from the electron gun. As a result, the fluorescent X-ray 114 corresponding to the composition is generated from the sample.
Since the fluorescent X-rays are generated in a direction wider than the surface of the sample, they are condensed by the curved crystal 103 for spectroscopy, and at the same time, X-ray spectroscopy is performed. For this reason, the sample 113 and the diffraction X-ray cutting aperture 115 are arranged so that the X-ray incident / emission angle θ to the spectroscopic curved crystal is the Bragg angle of the X-ray wavelength to be spectroscopically arranged on the Rowland circle having a radius of 40 mm. . Further, the curved crystal 103 for spectroscopy is arranged so as to be in contact with the apex of the Rowland circle. The wavelength of the X-ray to be detected can be changed by changing the arrangement of the curved crystal 103 for spectroscopy, the aperture 115 and the detector 116 behind the same along the Rowland circle and changing the angle of incidence and emission of the X-ray. it can.

When a metal plate containing titanium and vanadium was used as the sample 113 and the X-ray spectrum was measured by changing the X-ray entrance and exit angles θ, titanium and vanadium were clearly separated at θ = 35.7 ° and 32.1 °, respectively. And was observed.
From this, it was shown that the curved crystal for X-ray spectroscopy according to the present invention has appropriate spectral performance. Moreover, the radius of the Rowland circle can be reduced to 40 mm, and the size of the entire device can be reduced.

Example 9 Next, an embodiment of an electrode for a liquid crystal optical panel according to the third invention of the present application will be described. FIG. 23 is a drawing best showing the features of the present invention. In FIG.
Is a transparent electrode such as ITO, 202 is a stress-free (or extremely small) electrode portion, and 203 is a liquid crystal alignment film.

The electrode 203 shown in FIG. 23 is, for example, as shown in FIG.
It can be formed by the process as shown in FIG. That is, first, the liquid crystal panel drive wiring 2 is formed on the glass substrate 204.
A resist pattern 210 is formed in a region equal to or narrower than a portion shielded by 05 (same for both simple matrix and active matrix TFT) by using a normal photolithography technique. At this time, a resist such as photosensitive PI (positive type) or OMR-83 (negative type) is preferably used so that the resist can be easily removed in a later step. The exposure can be performed using ultraviolet light or far ultraviolet light. As described above, the gold single crystal thin film 202 ′ is formed on the substrate surface on which the resist pattern is formed.

As a method for forming a gold single crystal thin film, the gold crystal composed of a single crystal group is formed on the surface of the substrate by decomposing the gold complex shown in each of the above-mentioned examples to shift the gold in the solution to a supersaturated state. A method for forming a thin film can be appropriately selected and used.

Gold supersaturated in the solution is randomly deposited as nuclei on the substrate surface. After that, the nucleation continues for a while, but when a certain number of nuclei are formed, the nuclei stop increasing and the nuclei grow in a self-aligned single crystal. Then, by continuing the growth, the single crystals collide with each other to form grain boundaries. When the growth is further continued, the crystals collide with each other, grain boundaries are formed almost in the middle of the surfaces each made of a material having a high nucleation density, and the gold crystal thin film can be formed by covering the substrate surface. This film is defect-free, has low stress, has perfect orientation, and has excellent conductivity and thermal conductivity.

After the gold single crystal thin film having a desired film thickness is formed on the portion where the resist pattern is not formed as described above, the resist pattern and the gold single crystal formed on the resist are formed by using an ordinary resist removing agent. The thin film is removed at the same time.

IT conventionally used as a transparent electrode
O has a thickness of 1000 to 1000, which can ensure sufficient conductivity.
About 3000Å is required. For example, if the gold single crystal film is formed to the same thickness as the film thickness of ITO, the resist that covers the gold single crystal pattern is formed as follows by utilizing the fact that ultraviolet light and far ultraviolet light are sufficiently shielded. That is, FIG.
4 (e) and 4 (f), a resist is applied to the gold pattern forming surface, the glass substrate surface side is irradiated with ultraviolet light or far ultraviolet light to expose the resist, and then the resist is developed. The resist can be formed only on the gold pattern.

When ITO having a desired film thickness is formed by the sputtering method ((g) in the figure) and the resist is removed, an electrode surface which is a partially gold single crystal film as shown in (h) in the figure can be formed. it can.

By using this process, it is possible to form an electrode plate, as shown in FIG. 25, in which the gold single crystal pattern 202 is accommodated in the portion 208 which is shielded by the liquid crystal drive wiring portion. However, 212 represents an opening (non-light-shielding portion).

The electrodes produced as described above are made of ITO.
The stress caused by the problem solves the problem that the substrate is distorted and the gap of the liquid crystal panel is different between the center and the end of the panel. As a result, the orientation of the liquid crystal becomes uniform over the entire panel, and high-definition display is possible. Also,
Since the gap of each pixel can uniformly hold a desired value, it is possible to provide the liquid crystal panel excellent in gradation by maximally utilizing the electric power supplied by the transistor or the like.

Furthermore, according to the method for producing a gold single crystal film, the film is formed in a solution at about 30 to 100 ° C.
Compared with other film formation, it has an advantage that it is a low temperature process and at the same time a film can be formed in a large area.

It is not necessary to provide a portion having a low stress in all the portions shielded by the drive wiring portion, and a necessary and sufficient amount can be obtained depending on the stress generated in the process characteristics when forming the transparent electrode film, the direction, and the size. The low stress portion may be provided, and the pattern can be formed as shown in FIG. 26, for example. As a result, the gap between the center and the end of the liquid crystal panel, which is relatively large such as 3 to 5 inches, is made uniform, and high-definition display can be performed.

Example 10 FIG. 28 shows an example in which the gold single crystal thin film according to the present invention was used for an adhesive element. In the figure, 301, 302 and 303 are S
i substrate, 304 is a weight portion made of a Si substrate, 305 is a Si substrate that dynamically connects the weight portion 304 and the Si substrate 303 by adhesion, and 306 is a surface formed by plating on the Si substrate 301. Thickness of 2 μm and size of 500 μm with smoothness of about 20 angstroms
307 is a gold single crystal thin film, 307 is a gold single crystal thin film similar to the gold single crystal thin film 306 formed on the Si substrate 302, and 308 and 309 are the gold single crystals formed on both surfaces of the Si substrate 303. It is a gold single crystal thin film similar to the thin films 306 and 307.

Next, in the above structure, the Si substrates 301, 302 and 303 can be integrated by pressing the Si substrates 301 and 302 into each other from both sides of the Si substrate 303 with the load F, and at the same time, the Si substrate 301 and the Si substrate 301 can be integrated. The gap between 303 and the Si substrates 302 and 303 can be controlled to the thickness of the gold single crystal thin films 306 to 309. The load F was extremely small, and the Si substrates 301, 302, and 303 were adhered to each other simply by placing them quietly.

Si using the adhesive elements 306 to 309
The substrates 301 to 303 were bonded at room temperature in the air, and by using this bonding element, a structure of an acceleration sensor as shown in FIG. 28 could be easily manufactured.

The gold single crystal thin film as this adhesive element was formed as follows.

Potassium iodide (4 g) and iodine (6 g) were added to distilled water (500 ml), and the mixture was stirred and dissolved. Gold (3 g) was added to the solution.
100 ml of a solution obtained by charging and stirring was taken and put in a reactor, 500 ml of distilled water was further added and stirred therein, and then 100 m of hydroquinone was added to the resulting solution.
A film was formed by gradually adding 50 ml of an aqueous solution in which g was dissolved, and then immersing the Si substrate in this solution for 3 hours at room temperature.

Embodiment 11 FIGS. 29 to 31 are for explaining a second embodiment of an adhesive element, and in FIG. 29, 301, 302, 3
06 and 307 are the same as those in FIG. 28, and 310 is Si
The glass rod 311 that is mechanically connected to the substrate 301 by anodic bonding does not cause an excessive load at the time of bonding to the bonding elements 306 and 307, that is, a spring (plate having a small elastic coefficient for generating a minute load). 313, and 312 is a micrometer capable of freely moving the adhesive element 306 in the XYZ directions, and 313
Is a stage, 314 is a heat-resistant glass (trade name: Pyrex) for anodic bonding with the Si substrate 302, and 315 is a heater.

Next, in the above structure, the micrometer 3
When the adhesive element 306 and the adhesive element 307 are lightly contacted with each other by operating 12, the upper portion is pulled up (FIG. 3).
0). That is, the Si substrate 302 is also pulled up at the same time. In the next step, the Si is placed on the heat-resistant glass 314 on the heater 315 by operating the micrometer 312.
The substrate 302 is placed, and the heat-resistant glass 314 is placed on the Si substrate 30.
After anodic bonding to No. 2, the adhesive element 306 is slowly moved in the arrow direction (FIG. 31). By this method, it is possible to prevent particles and the like from being contaminated by conventional tweezers, and the Si substrate 302 and the heat-resistant glass 3 in a particle-free or dust-free state between the bonding surfaces.
Anodic bonding with 14 was possible.

The gold single crystal thin film, which is the adhesive element used in this example, was also formed on the Si substrate in the same manner as in Example 10.

[0112]

As described above, according to the present invention, by moving the gold in the solution containing the gold complex to the supersaturated state, no special device is required, and the atmospheric pressure and the temperature close to room temperature are obtained. Thus, a thin film composed of a gold single crystal and a gold single crystal group can be selectively formed. The gold single crystal thin film obtained by the present invention has a crystal plane 111-oriented with high accuracy in the direction perpendicular to the substrate, and can form an extremely smooth plane.

Using the thin film composed of the gold single crystal and the gold single crystal group, a surface acoustic wave device having a comb-shaped electrode having excellent resistance to mechanical migration and oxidation deterioration and having low electric resistance can be manufactured. . In addition, by forming a thin film of a gold single crystal group on a curved substrate having a desired shape, a polycrystalline type that has a small radius of curvature, high wavelength resolution and light focusing performance, and can obtain a more uniform image A curved crystal for X-ray spectroscopy is obtained.

By providing the gold thin film of the present invention as a portion for relieving the stress of the counter surface electrode in the portion shielded by the drive wiring portion of the liquid crystal optical panel, the gap between the end portion and the center portion of the panel is made uniform. By improving and making the gap uniform, the orientation of the injected liquid crystal is improved, and high-definition liquid crystal display can be performed even in a relatively large liquid crystal panel of 3 to 5 inches.

Further, by forming an adhesive element composed of the gold single crystal thin film of the present invention on a Si substrate, at the time of manufacturing a structure composed of a small and complicated Si substrate such as a micromachine, at room temperature and with a small load. S only by applying
There is an effect as particle-free and dust-free tweezers that enables the i substrates to be bonded to each other and is also capable of handling the Si substrate.

[Brief description of drawings]

FIG. 1 is a schematic cross-sectional view showing a manufacturing process of a gold single crystal thin film of the present invention.

FIG. 2 is a schematic plan view of the obtained gold single crystal thin film.

3A and 3B are views for explaining a substrate used in Example 1 of the present invention, in which FIG. 3A is a plan view and FIG. 3B is a cross-sectional view taken along line AA ′ of FIG. ).

FIG. 4 is a view showing a state where gold nuclei are formed on the substrate of FIG.

5 is a view showing a state in which a gold single crystal thin film is formed around the gold nuclei in FIG.

6 is a view showing a state in which a resist pattern is formed on the formed gold single crystal thin film of FIG.

FIG. 7 is a diagram showing the obtained comb-shaped electrode.

FIG. 8 is a diagram showing a substrate on which a Ti film used in Example 3 of the present invention is formed in a matrix.

9 is a view showing a state where gold nuclei are formed on the substrate of FIG.

10 is a diagram showing a state in which a gold single crystal thin film is formed around the gold nuclei in FIG.

11 is a view showing a state in which a resist pattern is formed on the formed gold single crystal thin film of FIG.

FIG. 12 is a diagram showing an obtained comb-shaped electrode.

FIG. 13 is a diagram showing a state in which a negative resist pattern is formed on a substrate in Example 4 of the present invention.

FIG. 14 is a view showing a state in which a gold single crystal thin film is formed on a portion of the substrate of FIG. 13 where a resist is not formed.

FIG. 15 is a diagram showing an obtained comb-shaped electrode.

FIG. 16 is a diagram showing a state in which a negative resist pattern is formed on a Cr film in Example 5 of the present invention.

17 is a diagram showing a state in which a gold single crystal thin film is formed on a portion of the substrate of FIG. 16 where a resist is not formed.

FIG. 18 is a diagram showing an obtained comb-shaped electrode.

FIG. 19 is a diagram showing a comb-shaped electrode.

FIG. 20 is a schematic view of a curved crystal for polycrystalline X-ray spectroscopy according to the present invention.

FIG. 21 is a schematic sectional view of the optical system described in Example 6.

FIG. 22 is a schematic diagram of the system described in Example 7.

FIG. 23 is a cross-sectional view of a liquid crystal panel embodying the present invention.

24 is a diagram illustrating a step of manufacturing a common electrode of the liquid crystal panel shown in FIG.

FIG. 25 is a plan view showing an example of a common electrode plate of a liquid crystal panel.

FIG. 26 is a plan view showing another example of the common electrode plate of the liquid crystal panel.

FIG. 27 is a cross-sectional view showing a general structure of a conventional TFT-LCD.

FIG. 28 is a schematic cross-sectional view showing the structure of an acceleration sensor using an adhesive element made of the gold single crystal thin film of the present invention.

FIG. 29 is a schematic view showing the constitution of another example using the adhesive element made of the gold single crystal thin film of the present invention.

FIG. 30 is a plan view of FIG. 29.
It is a schematic diagram which shows the state which pulled up the i board | substrate.

FIG. 31 is a schematic view showing a state in which heat-resistant glass is anodically bonded to the pulled-up substrate in FIG. 29 and the adhesive element is separated.

[Explanation of symbols]

 1 Substrate 2 Nucleation Surface 3 Gold Single Crystal Film 4 Grain Boundary 6 Comb Electrode 7 Resist 101 Substrate 102 Gold Single Crystal Thin Film 103 Curved Crystal 201 ITO Transparent Electrode 202 Low Stress Electrode Part (Gold Single Crystal Thin Film) 207 Common Electrode 301, 302, 303 Si substrate 306-309 Adhesive element (gold single crystal thin film)

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification number Reference number within the agency FI Technical indication H03H 9/145 Z 7259-5J (72) Inventor Tomoko Maruyama 3-30-2 Shimomaruko, Ota-ku, Tokyo No. Canon Inc. (72) Inventor Masami Hayashida 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (72) Keimei Fukuda 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. Within the corporation

Claims (28)

[Claims] 1. Obtained by decomposing a gold complex in a gold complex solution to transfer gold in the solution to a supersaturated state and growing a gold thin film consisting of a gold single crystal or a group of gold single crystals on the surface of a substrate. Gold single crystal thin film. 2. The gold single crystal thin film according to claim 1, wherein the single crystal is a single crystal having a high 111 orientation. 3. The gold single crystal thin film according to claim 1, wherein the gold complex contains [AuI ₄ ] ⁻ . 4. The gold single crystal thin film according to claim 1, wherein the gold complex contains [AuCl ₄ ] ⁻ . 5. The gold simple substance according to claim 1, wherein the decomposition treatment is carried out by volatilization of components constituting the gold complex from a solution system. Crystal thin film. 6. The decomposition treatment is performed by adding a reducing agent to a solution system.
5. The gold single crystal thin film according to any one of items 4 to 4. 7. A method of decomposing a gold complex in a gold complex solution to transfer the gold in the solution to a supersaturated state and growing a gold thin film composed of a gold single crystal or a group of gold single crystals on the surface of a substrate. A method for manufacturing a gold single crystal thin film. 8. The method for producing a gold single crystal thin film according to claim 7, wherein the single crystal is a single crystal having a high 111 orientation. 9. The method for producing a gold single crystal thin film according to claim 7, wherein the gold complex contains [AuI ₄ ] ^- . 10. The method for producing a gold single crystal thin film according to claim 7, wherein the gold complex contains [AuCl ₄ ] ⁻ . 11. The gold simple substance according to claim 7, wherein the decomposition treatment is performed by volatilization of a component constituting the gold complex from a solution system. Crystal thin film manufacturing method. 12. The method for producing a gold single crystal thin film according to claim 7, wherein the decomposition treatment is performed by adding a reducing agent to a solution system. . 13. In a surface acoustic wave element for generating and receiving a surface acoustic wave by at least one comb electrode provided on a piezoelectric substrate, the comb electrode is made of gold single crystal or
A surface acoustic wave device formed by a thin film of a gold single crystal group. 14. The surface acoustic wave device according to claim 13, wherein the thin film made of the gold single crystal or the gold single crystal group is the thin film according to claim 1. 15. A substrate in which a thin film made of the gold single crystal group is provided with a surface made of a material having a high nucleation density and a surface made of a material having a low nucleation density adjacent to each other in a gold complex solution. It is characterized in that by decomposing the gold complex, the gold in the solution is transferred to a supersaturated state, and a gold crystal thin film composed of a single crystal group is formed only on the surface of the material having a high nucleation density. The surface acoustic wave device according to claim 13. 16. The surface acoustic wave device according to claim 15, wherein the surface made of a material having a high nucleation density is a surface sufficiently fine to form a single nucleus. 17. The surface acoustic wave device according to claim 15, wherein the material having a high nucleation density is a semiconductor material. 18. The surface acoustic wave device according to claim 15, wherein the material having a high nucleation density is a conductive material. 19. The surface acoustic wave device according to claim 15, wherein the material having a low nucleation density is an insulating material. 20. A curved crystal for X-ray spectroscopy, wherein an X-ray diffraction layer made of a gold single crystal group oriented in a 111 direction in a direction perpendicular to the substrate surface is formed on a curved substrate surface having a desired shape. Curved crystal for polycrystalline X-ray spectroscopy. 21. The polycrystalline X-ray spectroscopy curved crystal according to claim 20, wherein the single crystal group is the gold single crystal thin film according to claim 1. 22. With respect to the orientation of the gold single crystal group with respect to the substrate surface, the peak half value width of the diffraction intensity curve by the X-ray diffraction method of the gold single crystal group is 10 ⁻² rad or less. 20 polycrystal type curved crystals for X-ray spectroscopy. 23. An electrode of a liquid crystal optical panel, characterized in that an electrode portion is provided in a process different from that of a portion of a portion which is shielded by a drive wiring from a portion which is not shielded from light. 24. The electrode according to claim 23, wherein the electrode in the portion shielded by the drive wiring is the gold single crystal thin film according to claim 1. 25. The electrode according to claim 23 or 24, which is used in a liquid crystal optical panel using a ferroelectric liquid crystal. 26. A hyperplane on a Si substrate.
1. An adhesive element comprising the gold single crystal thin film, wherein the gold single crystal thin film is provided, and the hyperplanes of the single crystal thin films are superposed on each other, and then the gold single crystal thin film can be bonded only by applying an extremely small load. 27. The adhesive element according to claim 26, wherein the application of the load is performed at room temperature. 28. The adhesive element according to claim 26, which has a flat plate shape.