JPS60193535A - Film forming device - Google Patents

Abstract

PURPOSE:To enable not only easy continuous accumulation of monomolecular films but also cleaning up of the liquid in a liquid tank by controlling the surface pressure of the monomolecular films so as to obtain desired surface density and interposing additionally a filter means in a liquid circulating system. CONSTITUTION:A circulating path 12 for a liquid and a filter means 16 are added to a liquid tank 3 contg. the liquid for spreading molecules for film forming. For example, a filter 16 which removes >=0.5mu dust is inserted into said tank. As a result, the visible dust is not admitted even after the device is used >=100 times, while in the prior art the visible dust is admitted in the tank 3 after just about 2-5 times (5-10hr in time) of use of said device. The easy continuous accumulation of the monomolecular films and the simultaneous cleaning up of the water in the water tank are made possible by the simple constitution of inserting the filter into the circulating system of the water flow path. The labor and time required for preparation for the accumulation are thus reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field The present invention relates to an apparatus for producing a thin film, which is a functional part of a semiconductor or optical device, and particularly relates to an apparatus for producing a thin film, which is a functional part of a semiconductor or optical device.

The present invention relates to an LB film manufacturing apparatus using a medium molecule accumulation method, that is, the Langmuir-Blodgett method (LB method).

BACKGROUND ART Conventionally, the use of materials in the semiconductor technology field and the optical technology field has mainly focused on inorganic materials that are relatively easy to handle. This is because the technological progress in the field of organic chemistry is compared to that in the field of inorganic materials, but the recent technological progress in the field of organic chemistry is remarkable.
It is said that the development of materials for aircraft has almost reached its limit. Therefore, there is a demand for the development of functional organic materials as new functional materials that surpass inorganic materials. The advantages of organic materials are that they are inexpensive, easy to manufacture, and highly functional. On the other hand, organic materials that have overcome heat resistance and mechanical strength, which have been thought to be inferior, have recently been created one after another. Based on this technical background, some of the functional parts (mainly thin film parts) of IC devices such as logic elements, memory elements, and photoelectric conversion elements, and optical devices such as microlens arrays and guiding waveguides. Or, from the proposal to replace the conventional inorganic thin film with an organic thin film, we ended up with a molecular electronic device or bio-related material in which a single organic molecule has functions such as a logic element or a memory element. Proposals to create logic devices (eg, bio-cheaps) have recently been announced by several research institutions.

Thin films used to create the various devices described above using such organic materials can be formed by a known single molecule accumulation method, that is, the Langmuir-Blodgett method (LB method).

The LB method refers to the parent tree group 1a and the hydrophobic group i in FIG.
The middle molecule l composed of b, that is, the membrane constituent material, is dissolved in a volatile solvent such as benzene or chloroform, and dropped onto the water surface surrounded by a frame 4 arranged in the water tank 3, and after the solvent evaporates. The monomolecular film 2 left on the water surface (at this point, it is a gas film) is transformed into a solid film by reducing the area surrounded by the frame 4 and increasing the areal density of the monomolecular film 2, which is then vertically immersed. In this method, the film is transferred to a substrate (not shown) using a method or a horizontal adhesion method.

However, according to this method, the area of a single molecule on the water surface decreases by the amount of middle molecule Hg transferred onto the substrate. In other words, since the monomolecular film (solid film) on the water surface is required to be uniform, when the monomolecular film is continuously transferred to the substrate E while keeping its areal density constant, Since the area surrounded by the frame gradually decreases and approaches 0, there is naturally a limit to the number of times it can be transferred.

<Disclosure of the Invention> The purpose of the present invention is to solve the above-mentioned problems, and for this purpose, the surface pressure of the monomolecular membrane is controlled so as to obtain a desired areal density, and furthermore, a filtration means is provided in the liquid circulation system. By interposing the monomolecular film, it is possible not only to easily and continuously accumulate the monomolecular film, but also to purify the liquid in the liquid tank.

The principle of the present invention will be explained below with reference to FIG.

When a monomolecular film 2 is spread on a water surface with a certain flow velocity, the monomolecular H2 is kept constant in the direction of water flow (direction of the arrow) due to the attractive force between the molecules constituting the monomolecular film 2 and the water. being pulled by the force of At this time, if there is a barrier 8 in the path of the monomolecular film 2 that blocks only the movement of the monomolecular film 2 without affecting the flow of the wood, the monomolecular film 2 will have a certain force. It is pressed against this barrier 8. In other words, the force of the middle molecular film 2 pressing against the barrier 8, in other words, the single molecule 1! 2 shows that the surface pressure can be easily controlled by changing the water flow rate. The present invention
It is characterized by applying this principle.

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that in each drawing, the same reference numerals represent the same structural members and have the same functions.

First, the first "j!" embodiment will be described with reference to FIG.

Stearic acid in the solvent chloroform at 1×10−]M/
0.1 m/! , 20cm/
When a drop is dropped in a region 9 (hereinafter referred to as the dripping region 9) of 1-flow as seen from the barrier 8 on the water surface flowing in the direction of the arrow at a speed of sec, the water surface surrounded by the barrier 8 is A single molecule +1Q 2 of approximately 120 cm' was formed. When the surface pressure of single molecule IIA 2 was measured using a surface pressure measuring device (not shown), it was 24 dyne/cm (7)
It was confirmed that the monomolecular film 2 had formed the desired solid state. Furthermore, increase the speed to 15 to 25 cm/s.
When the surface pressure was changed within the range of ee, it was confirmed that the surface pressure changed almost in proportion to this, and it became clear that the surface pressure could be controlled by the flow rate. Moreover, at this time, the amount of dripping is also 0.
When the amount was varied within the range of 0.05 to 0.3 ml, it was confirmed that the surface pressure also varied in proportion to this. In other words, it has become clear that the surface pressure can also be controlled by the amount of dripping. On the other hand, in the area 10 near the barrier 8 (hereinafter referred to as the accumulation area IO), when the monomolecular film was accumulated on the substrate by the vertical dipping method, a good accumulation rate of 80 to almost 100% was obtained. I was able to obtain a membrane.

Then, while controlling the flow rate so that the surface pressure remains constant,
In addition, as a result of repeating the accumulation operation while compensating for the decrease in the monomolecular film 2 transferred to the substrate in the accumulation region 10 with the droplets r of the film constituent material in the dropping region 9, continuous accumulation, which was difficult with conventional equipment, was performed. This could be achieved easily.

Next, a second embodiment will be explained according to FIG.

This embodiment is characterized in that, in the first embodiment, the outflowing water is recycled and returned to the aquarium, thereby reusing the water. In FIG. 7, Pyrex glass tubes are used for most of the circulation path 12, and the water accumulated in the water tank 13 is pumped out by a pump 14, and the flow rate is controlled by a gate valve 15. .

In this way, by circulating the water that flows out, there is no need for a system to replenish lost water, and the entire device becomes more convenient.

Next, a third embodiment will be described with reference to FIG.

This embodiment is characterized in that a dust removal filter 1B is inserted in the middle of the circulation path 12, as shown in the figure. Specifically, when the filter 16 that removes dust of 0.5 microns or more was inserted, it was necessary to use the device only 2 to 5 times (5 to 10 hours), and the amount of dust that could be seen in the aquarium 3 was increased. 100 pieces of garbage were confirmed.
No visible dust was found even after using the device more than once. In other words, with a simple configuration of inserting a filter into the circulation system of the water channel, it is possible to not only easily and continuously accumulate a monomolecular film, but also to deceive the water in the aquarium at the same time. , I was able to save 11 days and time required for preparation for accumulation.

Next, a fourth embodiment will be explained according to FIG.

As shown in the figure, this embodiment is characterized in that a P)l control device 3o is provided in a part of the circulation path 12. Specifically, when predetermined amounts of sodium hydroxide solution and hydrochloric acid were respectively charged into the device using a micro cylinder, diffusion of sodium hydroxide and hydrochloric acid, which was difficult in the past, was achieved in this example. Because of the flowing flow, it became possible to obtain a predetermined pH within a very short time (5 to 30 minutes). Furthermore, it is clear that according to this device, it is also possible to control the pH while the monomolecular film is formed on the water surface.

Next, a fifth embodiment will be explained according to FIG. 7.

In this embodiment, as shown in the figure, the circulation path 12
It is characterized in that a heat exchanger 31 is provided in a part of the unit.

Specifically, it has a diameter of 378 inches and a wall thickness of 0 through which the circulating water passes.
．． A heat exchanger 31 is provided in which a 5-inch Pyrex glass tube is wrapped around a hollow copper pipe. The temperature of the circulating water was controlled by flowing a liquid at that temperature. As a result, the water in the aquarium was reduced by 5 to 8
It was possible to control the temperature within a range of 0°C with an accuracy of ±0.5°C. Therefore, it became possible to easily control the temperature conditions during monolayer accumulation. Furthermore, it is clear that according to the present apparatus, it is also possible to control the temperature while the monomolecular film is formed on the water surface.

Next, a sixth embodiment will be described with reference to FIG.

This embodiment is a slight improvement of the first embodiment. That is, in the first embodiment, in the accumulation region lO, the flow of water is disturbed by the substrate (not shown) that is submerged in water in the case of accumulation by the vertical immersion method, as well as the barrier 8, and the monomolecular film 2 is bent. This is undesirable because the surface pressure, which should be constant, may fluctuate temporarily. Therefore, in this embodiment, by varying the depth of the water tank and slowing down the flow (flow velocity) of water in the accumulation area IO,
The first embodiment has been improved. Specifically, a region 11 (hereinafter referred to as
This is called a surface pressure forming region 11. ) is made shallow to lc■, and the depth of the water tank in the cumulative area lO is set to 1.
(The depth was increased to 1'c. As a result, the surface pressure forming area 11
Even if the flow velocity at is 20CII/SeC, the cumulative area l
The flow rate in O was about 1/10, and when the middle molecular film was accumulated on the substrate, the yield was 20-100% in the first example, but it was 50-100%. did.

Next, a seventh embodiment will be described with reference to FIG.

This embodiment is a modification of the sixth embodiment, and is an improvement over the first embodiment by varying the width of the water tank and slowing down the flow velocity in the accumulation region 10. Specifically, the width of the water tank in the surface pressure forming region 11 including the dripping region 9 was narrowed to 2 cm, and the width of the water tank in the accumulation region 10 was widened to 20 cm. As a result, the surface pressure forming area 11
Even if the flow velocity at is 20 cm/secC, the cumulative area IO
The flow rate was reduced to about 1/10, and when the monomolecular film was accumulated on the substrate, the yield was 2 in the first example.
It may have been 0-60%, but it was 50-100%.

Next, the eighth embodiment will be described according to FIGS. 1θ (a) and (b).

In this embodiment, a single aquarium is partitioned off only near the water surface by a plurality of (five in this embodiment) fan-shaped barriers 8.
Hereinafter, the partitioned areas will be referred to as blocks. ), water flows into each block from near the center toward the outer periphery. The apparatus according to this embodiment has the following features regarding the ability to accumulate the monomolecular film 2 on the substrate and the ease of continuous accumulation.
This is similar to the first embodiment.

Furthermore, a unique feature of this embodiment is that it is possible to easily accumulate different types of single molecules (heterostructure). That is, in each block, a monomolecular film of a different material is spread on the water surface in advance, and after the monomolecular film is accumulated on the substrate H using the vertical dipping method in one block, the same operation is performed in another block. By repeating this process, it was possible to easily form a hetero-accumulated film (the molecules constituting the middle molecular film differ in the direction of accumulation). At this time, it is possible to move between blocks in the gas phase or in the aqueous phase, so for example, a heterojunction in a film forming a Y-type film has hydrophobicity between the parent wood groups as well. They were also able to freely set their own standards among the base comrades.

Finally, the ninth embodiment is shown in FIGS. 11(a) and (b).
Explain according to the following.

This embodiment is characterized in that the barrier 8 in the previous embodiment is configured to be movable in the horizontal direction. Specifically, the barrier 8 is operated by a motor (not shown) (however,
It is also possible to do it manually. ), it becomes possible to wash away the unnecessary middle molecular film 2 on the water surface and clean the water surface, greatly reducing the effort and time required for preparation for monomolecular film accumulation. I was able to do that.

As explained below, the present invention provides for easy accumulation of 1IIU of monolayer by intervening a filtration means in the liquid circulation system as explained below. This has the effect of reducing the effort and time required for preparation.

[Brief explanation of drawings]

FIG. 1 is a schematic diagram of a conventional LB film manufacturing apparatus, FIG. 4 is a schematic diagram of the second embodiment, FIG. 5 is a schematic diagram of the third embodiment, and FIG. 6 is a schematic diagram of the fourth embodiment. 7 is a schematic configuration diagram of the fifth embodiment, FIG. 8 is a schematic sectional view of the sixth embodiment, FIG. 9 is a schematic perspective view of the seventh embodiment, 1st
Figures (a) and (b) are a schematic perspective view and a cross-sectional view of the eighth embodiment, respectively, and Figures 11 (a) and (b) are a diagram of the ninth embodiment before the barrier 8 is removed and It is a schematic sectional view after removing. 1--1 Monomolecule 1a-m- Parent tree group 1b-m- Water curtain 2-m- Monomolecular film 3-m- Water tank 4- Frame 7-m- Water flow generator 8-m- Barrier 9-m - Droplet F region 10-m-Accumulation region 11-m-Surface pressure formation region 12-m-Circulation path 13-m-Water tank 14-m-Pump 15-m-Gate valve 16--Filter 21-- - pH sensor 30--- pH control device 31--1 Heat exchanger 32--1 Temperature control device 33-m-Temperature sensor whistle 6m Figure ■

Claims (1)

[Claims] 1. A film forming apparatus comprising: a liquid tank containing a liquid for developing molecules for formation 11II;