JPH0394857A - Method and device for producing organic molecule ultrathin-film and surface pressure gage - Google Patents

Abstract

PURPOSE:To isotropically compress an ultrathin-film and to produce a high quality LB film by changing water level utilizing the conical shape of a water tank. CONSTITUTION:The truncated conical water tank 11 is prepared, and the truncated conical part is narrowed toward the upper part or widened toward the upper part. The pure water in a second pure water reservoir 13 is then injected into the tank 11 to a specified level, and an org. molecule ultrathin-film forming material is dripped on the water surface at the specified level to form the thin film thereon. Pure water is again injected into or extracted from the tank 11 to move the water level to reduce the area of the water surface, hence the ultrathin-film is isotropically compressed, and the compressed ultrathin-film is collected by a collector 16.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a method for producing an isotropically compressible ultra-thin film of organic molecules, an apparatus for producing the same, and a surface pressure gauge used in this production method.

[Prior art and its problems] Ultra-thin organic molecule film (Langmuir-Blodget
T-film: Hereafter abbreviated as LB film) In the production device, it is completely molecular]
The process of forming a monomolecular film consisting of layers (approximately one billionth of a meter thick) is repeated and the monomolecular films are stacked to form an ultra-thin multilayer film.

Hereinafter, conventional problems in creating such an ideal monolayer consisting of a single layer of molecules will be described.

In order to create an ultra-thin film of organic molecules, several molecules of material are dropped onto the water surface, and then the organic molecule layer on the water surface is appropriately compressed to bring the individual molecules into close contact with each other. They must be made so that they do not overlap. Therefore,
Water surface compaction is considered one crucial process to create homogeneous LB films.

In conventional LB film forming apparatuses, when compressing the water surface, the water surface is generally compressed in only one direction. For this reason,
Nonuniform stress was applied to the LB film on the water surface, and it was difficult to take a homogeneous pattern, especially for a highly rigid film. In order to solve this problem, a production device that compresses the water surface from multiple directions has recently been devised and is being put into practical use.

FIG. 1 is an example of this, and shows the configuration of an LB film forming apparatus that compresses the water surface from two directions.

This two-way compression type LB film production device uses water}! 1 is provided with a water surface compression barrier 2 that moves on the water surface from left to right, and further narrows in width from left to right.
A moving wall 3 (wall made of tape) is provided that goes around the pair of wall plates. Then, the water surface compression barrier 2 installed in the aquarium 1 moves quietly on the water surface from left to right, and at the same time, the tape wall 3 also moves as shown by the arrow to remove the organic matter present on the water surface. Molecules are swept to the right,
2 by water surface compression barrier 2 and moving wall 3
Achieves directional compression.

Compared to the water surface compression method (unidirectional compression method) using only a barrier without the moving wall 3, this method improves the uniformity of the stress acting on the ultra-thin film on the water surface, making it possible to create a high-quality LB film. It has become.

However, even with this method, complete isotropic compression of organic molecules is impossible, and one of the major problems is considered to be that it is difficult to create a monolayer that is perfect at the molecular level.

In addition, with conventional ultra-thin film production equipment, the water level does not rise at all even when the water surface begins to compress, so in order to collect the LB film on the water surface onto a substrate such as a glass plate, it is necessary to drive It is necessary to lower the substrate from above the water surface until it is in close contact with the water surface using the type film collecting device 5, but there is vibration of the water surface due to the motor drive, and it is difficult to control the quality of the ultra-thin film on the water surface. There was a problem.

Furthermore, in the conventional LB film forming apparatus, the water level does not change due to compression. The surface pressure 21 used for this purpose will be explained with reference to FIG. 2, for example. Figure 2 shows the principle of the most commonly used hanging plate method, in which a solid plate 6 made of hydrophilic glass or mica is suspended above the water surface to be measured, and a portion is immersed in the water. Soak. At this time, the force acting on the plate 6 is considered to be the sum of gravity ε surface tension acting downward and the buoyant force of the portion immersed in water acting upward. However, the buoyancy of the identification plate 6 in the air is ignored. The surface pressure (surface tension) is then measured using a torsion balance 7 that utilizes the torsional stress of the gold i-wire. At this time, as can be seen from the operating principle described above, in order to measure the surface pressure, among the forces acting on the plate, forces other than the surface tension must always remain constant during measurement. This condition is automatically satisfied in conventional LB film forming apparatuses in which the water surface does not rise due to compression of the water surface.

[Problems to be Solved by the Invention] The present invention has been made to solve the above-mentioned problems. It is an object of the present invention to provide a method for manufacturing an ultra-thin organic molecule film and an apparatus for manufacturing the same, in which stress can be applied and compressed completely isotropically to the thin film.

Fourth, it is an object of the present invention to provide a method for producing an ultra-thin organic molecule film and an apparatus for producing the same, which allows the produced ultra-thin organic molecule film to be taken out without vibrating the water surface.

Furthermore, an eleventh object of the present invention is to provide a surface pressure gauge suitable for the method for producing an ultra-thin film of organic component f1 and the apparatus for producing the same according to the present invention.

[Means to solve the problem]

The method for producing an ultra-thin film of a-molecules according to the present invention for achieving the desired results includes preparing a water tank in which at least a portion of the tank is shaped like a truncated pyramid, and the truncated-pyramid-shaped portion is directed upward. an upper part arranged so as to narrow or spread toward a stop; a lower part to inject pure water into the water tank until it reaches a predetermined level of the truncated cone shaped part; and a water surface at the predetermined level. By dropping a material for forming an ultra-thin film of organic molecules onto the top of the tank and forming an ultra-thin film of organic molecules there, and by re-injecting or extracting pure water into the water tank, The water surface level is moved so that the surface area of the water surface forming the thinning is reduced, and the ultra-thin film of organic molecules is isotropically compressed using this table, and the compressed ultra-thin film of organic molecules is collected. What is the process and what is done?

Further, the organic molecule ultra-thin film manufacturing apparatus of the present invention for achieving the above-mentioned goal has at least a part of the shape in a truncated pyramid shape, and the truncated pyramid shape part narrows toward the end. A water tank arranged to spread upward, a means for injecting and extracting pure water into the water tank, and a material for forming an ultra-thin film of organic molecules dripping onto the water surface in the water tank. and a means for collecting an ultra-thin film of organic molecules formed on the water surface in the aquarium, the collecting means comprising:
Preferably it is fixed in place.

To achieve the above object, the surface pressure gauge of the present invention is a surface pressure gauge for determining the surface pressure of a membrane formed on water, which is suspended above the water surface and partially immersed in water. a solid plate connected to the solid plate, a means for detecting and measuring the surface pressure applied to the solid plate, and a means for monitoring the height of the water surface and outputting an output signal corresponding to Ωi of the water quotient. water surface height sensor means; a motor controller connected to the sensor means and outputting a motor drive signal based on an output signal from the sensor means; connected to the motor controller and outputting a motor drive signal based on an output signal from the motor controller h roller; (The solid plate is equipped with a motor that raises or lowers the solid plate so that the immersion depth of the solid plate in water becomes a predetermined depth at S.

Another surface pressure gauge of the present invention for achieving the above object is as follows:
A surface pressure gauge that measures the surface pressure of a membrane formed on the water surface includes a solid plate suspended above the water surface and partially immersed in water, and a surface connected to the solid plate and applied to the solid plate. means for detecting pressure; water surface height sensor means for monitoring the height of the water surface and outputting an output signal corresponding to the height of the water surface; connected to the sensor means and the surface pressure detection means, respectively; Calculate the underwater immersion depth of the solid plate based on the output signals from the sensor f and stage, manually input the surface pressure detection signal from the surface pressure detection means, and calculate the surface pressure detection signal ε from the underwater immersion depth calculation value. , and an arithmetic processing device L that measures the surface pressure applied to the same body plate.

[Operations and Effects] According to the method and apparatus for producing an ultra-thin film of organic molecules of the present invention, the ultra-thin film can be isotropically compressed by utilizing the conical shape of the water tank and changing the water surface. 3 quality LB films can be created. Moreover, since the only operation involved is changing the water surface level, the device is simple and easy to control during operation.

Furthermore, since the membrane collecting device can be fixed, there is an advantage that the problem of water surface vibration is eliminated.

Furthermore, according to the table bending force meter of the present invention, the plate can be moved to the A iE position in response to changes in the water level, or the submerged plate can be calculated i, 'r, table translation. It is possible to measure pressure accurately.

[Example] FIG. 3 shows an example of an apparatus for producing an ultra-thin film of perfectly homogeneous 6-compressed molecules according to the present invention. In this device, a truncated cone-shaped water tank 11 with an open top and bottom is arranged so as to narrow in seven directions. A first pure water reservoir] 2 is provided at the bottom of this water tank 11, and this first pure water reservoir 12
is bolted to the 11-color flange part of the aquarium. The water tank and pure water reservoir ε are all stainless steel (SUS304)
The inner surface is coated with Teflon to improve water repellency and at the same time prevent metal ions from dissolving in the pure water from the water tank and pure water reservoir. The first pure water reservoir 12 is connected to the water tank 1 via a Teflon vibrator 4.
1 is connected to a second pure water reservoir 13 for supplying pure water. A Teflon valve 15 is attached to the vibrator 14. Further, on both sides of the upper water tank 11, a membrane collecting device 16 inserted into the tank is fixedly provided.

In the method of the present invention, the second pure water reservoir 13 is first filled with pure water, the valve 15 is opened, the pure water from the second pure water reservoir 13 is injected into the first pure water reservoir 12, and the water level of the first pure water reservoir 12 is When the height of ε matches that of the upper flange, drop the L8 membrane material into the water. After that, by raising the water level in the water table 11 and reducing the surface area of the water surface, the LB above the water surface is
Compress the membrane completely isotropically. Then, when the LB membrane above the water surface is compressed by a desired amount, the membrane is collected by a fixed type membrane collecting device 16 installed above the LB membrane.

In this way, in the bag holder of the present invention, since the water level rises as it is compressed, there is no need to move the loading haze repeatedly, and the LB
Vibration of the water surface, which is one of the major problems in film production, can be prevented.

The aquarium of the present invention only needs to have at least a portion with a truncated weight shape. Further, the water tank may be arranged so as to expand upward. In this case, the LB film is isotropically compressed by lowering the water surface level on which the B film was formed.

Next, the case where the surface pressure of the present invention is 1 will be explained.

As mentioned above, in conventional LB film production equipment, the water level does not fluctuate due to compression, so ``forces acting on the plate other than surface tension must always remain constant during measurement.'' 5 conditions However, in the device of the present invention, this condition is not satisfied because the water level changes with compression.

In view of the above problems, the configuration of a surface pressure gauge proposed for the device of the present invention is shown in FIGS. 4 and 5. The surface pressure gauge shown in FIG. 4 includes a solid plate 20, which is suspended above the water surface 21 by a metal wire 22 and partially immersed in water. A torsion balance 23 is connected to the metal wire, and the surface pressure of the LB membrane above the water surface can be detected and measured by this torsion balance. The configuration of this torsion balance is well known (edited by the Chemical Society of Japan, New Experimental Chemistry Course, Boundaries and Colloids,
(See Maruzen Co., Ltd., 1978, pp. 449-452).

The present invention includes a water surface height sensor means 24 that constantly monitors the height of the water surface using a mechanical or optical method and outputs an output signal corresponding to the height of the water surface. A seventh controller 25 is connected to this sensor means 24, which outputs a motor drive number 1d based on the output signal from the sensor means, and the motor controller 25 is further connected to an output number 1d from the motor fan l/roller. A motor 26 is connected to the motor 26, which is driven by the motor. This motor is attached to one end of the scale 2, and inside the motor casing,
A guide bar 27 having a spiral groove formed on the outer circumferential surface passes through the guide bar 27 vertically. When the motor is driven, the torsion scale is raised or lowered together with the motor, so that the immersion depth of the same body plate in water is always a predetermined depth.

On the other hand, the surface JE force meter shown in Fig. 5 is basically the same as that shown in Fig. 4. It uses the hanging plate method, but it has four beams as shown in Fig. 4, and the torsion scale does not move up and down, but instead uses water. The depth at which the solid plate 20 sinks into the water changes depending on the height of the song 2]. The surface pressure gauge of the present invention includes a solid plate 20, which is suspended above the water surface by a metal wire 22 and partially immersed in water. A torsion scale 23 is connected to the gold 14 wire, and this t
The scale measures the surface pressure applied to the body plate. Further, a detection means 30 for detecting surface pressure is connected to the torsion balance 23, and a detection II word is outputted from the detection means to an arithmetic processing unit 31. This surface pressure 1 is further equipped with a water face height sensor means 24 which monitors the height of the water surface and outputs a force signal corresponding to the height of the water surface. The sensor means is connected to the arithmetic processing device 31,
The detection signal is sent to the arithmetic processing unit 31. This arithmetic processing unit 31 determines whether the solid plate is immersed in water based on the output signal from the previous sensor means 24. A calculation is performed to correct the change in the if force applied to the solid plate from the r It measures the surface pressure applied to the body plate. The measurement results are displayed on the display device 32. That is, the 7lt calculation processing device 31
Then, when the height of the water surface changes, the buoyancy force due to water acting on the solid plate 20 changes, but the change in the buoyancy force is proportional to the length of the fixed plate submerged in the water surface, so the height of the water surface changes. An electric signal proportional to the buoyancy force is manually inputted to the arithmetic processing unit 31, and the change in buoyancy is corrected through arithmetic processing.

The principle of correction based on the deduction process will be described below, taking the hanging plate method as an example. In the suspended plate method, the forces acting on the plate are thought to be the sum of gravity and surface tension acting downward, and the buoyancy of the part immersed in water acting upward. {jl t,, the buoyancy of the solid plate in air is ignored. This can be expressed as an L-order equation.

F-mg+27(w+t)eosθ-ρ,gw
ih (1) formula, where F is the force acting on the plate at the same time, m is the mass of the suspended plate,
g is the gravitational acceleration, γ is the surface tension, and w, i, and h are the width and thickness of the suspension plate, and the length of the portion of the suspension plate submerged in water, respectively. Generally, it is used under the condition of θ-0, so (1
) can be written as follows.

F-mg+2γ (w 10t)-ρ. gwti (2) formula In this formula (2), the first term on the stone side is the force applied to the suspension plate, the second term is the surface tension, and the third term is the buoyant force applied to the part of the suspension plate submerged in water. It is.

Now, in this device, the height of the water surface changes as the water surface is compressed, but when the height of the water surface is h1, the force applied to the suspension plate is F, and as the height of the water surface changes, h2. ! :． Let F2 be the force applied to the single plate when this happens. These situations can be expressed using equations as follows by applying equation (2).

F1 -rr+g+2 7 (w+t)'
D − gw j h, (3) formula F2 −mg+27 (w+t) -ρ, gwth2
(4) Equation ε where there is no ultra-thin molecular material on the water surface 7, F1 and F2
If we make corrections so that they are equal, we can calculate this from s, F2-F. →−ρ− gwt (h2 h+) (5)
The formula becomes In this device, the water surface height sensor outputs electrical signals according to the values of h2 and h1, so if the arithmetic processing unit performs calculations based on equation (5) and makes corrections, the above measurement method can be applied. is realized.

Next, experiments conducted using these devices will be explained. A commonly used method for observing the applied stress distribution state due to compression of the water surface is to float talc powder on the water surface instead of the organic molecular material and visually observe how the talc is swept up. Using this method, we observed the water surface compression of this prototype device. As a result, no stress concentration was observed at the edges of the water tank or around the barrier, which was observed in the conventional device.

Next, a diacetylene derivative (manufactured by Wako Pure Chemical Industries, Ltd., trade name, L8
203) was used as the material to actually create an LB film.
Ta. As a result, no stress concentration was observed in the polymer film, which had increased rigidity by irradiating the LB film on the water surface with ultraviolet rays.
It was confirmed that high quality LB membrane could be collected.

Using a Fourier transform infrared spectrophotometer (FTIR) to determine the orientation of the molecules that make up the ultra-thin model, we found that the film-forming molecules used in the experiment were different from the conventional method shown in Figure 1. With the device, the angle was 60 to 70 degrees to the substrate, but when this device was used, it was measured to be at an angle of about 80 degrees, indicating that the stress was uniform. Therefore, it was quantitatively confirmed that a high-quality ultra-thin film could be obtained.

In addition, in the second embodiment, the surface pressure gauge is classified as a suspension plate method, but the present invention is not limited to the above embodiments, and can be applied to other surface pressure gauges classified as a suspension plate method. Alternatively, it can also be applied to a known surface pressure gauge such as a surface pressure if1 aneroid type surface pressure gauge classified as a float method.

[Brief explanation of drawings]

Fig. 1 is a perspective view of a conventional apparatus for producing ultra-thin organic molecule films, and Fig. 2 is a diagram showing a conventional surface pressure of 1'. FIG. 3 is a perspective view showing an example of an apparatus for producing an ultra-thin organic molecule film of the present invention, FIG. 4 is a diagram showing an example of a surface pressure gauge of the present invention, and FIG. 5 is a diagram showing an example of a surface pressure gauge of the present invention. It is a diagram showing another example. 11... Water tank, 12... First pure water reservoir, 13... Second pure water reservoir, 14... Vibrator, 15... Valve, 16
...Membrane sampling device, 20...Fixed option, 21...Water surface, 22...Gold bending wire, 23...Torsion balance, 24...
Sensor means, 25...Sweater jacket, 26...
- Motor, 27... Guide rod, 30... Surface pressure detection r stage, 31... Arithmetic processing unit, 32... Display device.

Claims (5)

[Claims] (1) A step of preparing an aquarium having at least a portion shaped like a truncated cone and arranging it so that the truncated cone shaped portion narrows upward or widens upward; and the decapitation. There is a process of injecting pure water into the water tank until it reaches a predetermined level in the cone-shaped part, and dropping a material to form an ultra-thin film of organic molecules onto the water surface at the predetermined level. By forming the thin film and re-injecting or withdrawing pure water into the water tank, the water surface level is moved so that the surface area of the water surface on which the ultra-thin film of organic molecules is formed becomes smaller, and this results in the above-mentioned A method for producing an ultra-thin organic molecule film, comprising: isotropically compressing the ultra-thin organic molecule film; and collecting the compressed ultra-thin organic molecule film. (2) A water tank having at least a part of the shape shaped like a truncated cone and arranged so that the truncated cone shape part narrows upward or widens upward, and pure water is contained in the water tank. means for injecting and extracting the organic molecule ultra-thin film formed on the water surface in the aquarium; An apparatus for producing ultra-thin films of organic molecules. (3) The apparatus for producing an ultra-thin film of organic molecules according to claim 1, wherein the film collecting means is fixed at a predetermined position. (4) A surface pressure gauge that measures the surface pressure of a membrane formed on a water surface, comprising: a solid plate suspended above the water surface and partially immersed in water; and a solid plate connected to the solid plate and connected to the solid plate. means for detecting and measuring applied surface pressure; water surface height sensor means for monitoring the height of the water surface and producing an output signal corresponding to the height of the water surface; a motor controller that outputs a motor drive signal based on the output signal; and a motor controller that is connected to the motor controller and raises the solid plate so that the immersion depth of the solid plate in water becomes a predetermined depth based on the output signal from the motor controller. or a surface pressure gauge equipped with a motor that lowers the surface pressure. (5) A surface pressure gauge that measures the surface pressure of a membrane formed on a water surface, comprising: a solid plate suspended above the water surface and partially immersed in water; and a solid plate connected to the solid plate and connected to the solid plate. means for detecting applied surface pressure; water surface height sensor means for monitoring the height of the water surface and outputting an output signal corresponding to the height of the water surface; connected to the sensor means and the surface pressure detection means, respectively; Calculating the underwater immersion depth of the solid plate based on the output signal from the sensor means, inputting a surface pressure detection signal from the surface pressure detection means, and using the surface pressure detection signal and the underwater immersion depth calculation value, A surface pressure gauge equipped with a calculation processing device that measures the surface pressure applied to a solid plate.