KR0144636B1 - Method for manufacture and apparatus of langmuir-blodgett thin film - Google Patents

Abstract

In order to improve the known Langmuir-Blodgett (LB) thin film production apparatus and method, an LB thin film production apparatus and method having an electric field applied thereto are described. The LB thin film manufacturing apparatus to which the electric field of the present invention is applied comprises: a main body 2 for containing a mixed solution of water and a polymer; A substrate (1) immersed in the water and polymer mixed solution in a direction perpendicular to the surface of the solution; A barrier (3) arranged on a side opposite to the substrate surface in a direction parallel to the substrate surface; It consists of a pair of electrodes 4 formed on the inner wall of the barrier opposite the substrate surface and arranged to form a longitudinal electric field. A voltage is applied to the electrode 4 provided on the barrier, the barrier 3 is gradually approached in the direction of the substrate 1, and then the substrate is gradually lifted in the vertical direction of the surface of the solution. LB thin films aligned with each other are deposited. According to the LB thin film manufacturing apparatus of the present invention, the LB thin film aligned in any direction as well as the LB thin film aligned in the transverse direction according to the installation position of the electrode can be obtained.

Description

An improved apparatus and method for producing a Langmuir-Blodgett thin film by applying an electric field.

Figure 1 (a) is a plan view of a conventional Langmuir-Bloze (LB) thin film manufacturing apparatus.

(B) is a longitudinal cross-sectional view of a well-known LB thin film manufacturing apparatus, and a partial enlarged sectional view of the board | substrate site | part in which LB thin film is formed.

FIG. 1C is a front view of the substrate showing an enlarged LB thin film formed by a known LB thin film device and its bonsai arrangement.

Fig. 1 (d) is an enlarged view of the molecular arrangement appearing on the side of the substrate when a polymer having a hydrophilic group and a hydrophobic group is formed by a known LB thin film production apparatus.

2A is a plan view of an LB thin film manufacturing apparatus to which an electric field in the longitudinal direction of the present invention is applied.

(B) of FIG. 2 is a longitudinal cross-sectional view of the LB thin film manufacturing apparatus which applied the electric field of the longitudinal direction of this invention.

FIG. 2C is a front view of the substrate, in which the LB thin film and the arrangement of the molecules thereof are formed when the longitudinal electric field of the present invention is applied.

Figure 2 (d) is an enlarged view of the substrate side array of the polymer having a hydrophilic group and a hydrophobic group of the present invention.

(F) of FIG. 2 shows that a polymer having a hydrophilic group and a hydrophobic group of the present invention and formed on the side of the substrate when a polymer having a symmetrical structure in the axial direction is formed by an LB thin film production apparatus applying a longitudinal electric field. Magnified view of molecular arrangement.

3A is a plan view of an LB thin film manufacturing apparatus to which an electric field in a lateral direction of the present invention is applied.

FIG. 3B is a front view of the substrate showing an enlarged LB thin film and its molecular arrangement when a lateral electric field of the present invention is applied.

4 is a Π-A graph showing the relationship between the surface pressure (Π) and the effective area per molecule (A) required for monomolecular film formation.

* Explanation of symbols for main parts of the drawings

Substrate to form a 1: LB thin film

2: Main body of LB thin film manufacturing apparatus

3: Barrier of LB thin film manufacturing equipment

4: An electrode installed on the barrier of an LB thin film manufacturing apparatus to apply an electric field to a substrate.

5: An electrode for applying a transverse electric field to the substrate.

6: water

7: A polymer that floats on the water or forms an LB thin film deposited on a substrate.

8: A hydrophilic group of a polymer having both hydrophilic and hydrophobic groups.

9: A hydrophobic group of a polymer having a hydrophilic group and a hydrophobic group at the same time.

The present invention relates to the production of LB thin film, and more particularly, to an LB thin film manufacturing apparatus and method capable of forming a film while making its constituent molecules in a uniform alignment.

In the related art of the present invention, Langmuir studied a monomolecular organic film behaving on a liquid surface in 1917, and then, by Langmuir and Blodgett, these steps A technique for forming a molecular organic film has been developed. In Fig. 1 (a) to (d), a conventional LB thin film manufacturing apparatus used by Langmuir and Blojet is shown. According to the conventional LB thin film device, as the two barriers gradually approach toward the substrate, the polymer floating on the water maintains (forms) a dense and uniform monomolecular film due to the presence of hydrophobic groups of the polymer. Gradually lifting 1) in the vertical direction causes the polymer to stick to the substrate as shown in (b), (c) and (d) of FIG. 1 to form a thin and uniform monolayer thin film on the substrate. . A conventional method of approaching the barrier to a substrate will now be described with reference to FIG. In other words, as the barrier gradually approaches toward the substrate, the effective area per molecule becomes smaller. At this time, the movement between the molecules floating on the surface of the water initially forms a gas phase, and as the gap between molecules narrows, it changes to a solid phase through the liquid phase. After passing through the effective area A ₁ , the boundary point between the liquid and solid phases, the membrane overlaps the membrane and the monomolecular membrane collapses. Therefore, in order to form a thin film with a single molecule, the substrate must be lifted just before the transition from the liquid phase to the solid phase (A ₁ ).

The monomolecular film formed by the known apparatus shown in FIG. 1 is called Langmuir-Blodgett (LB) thin film. Using the conventional LB thin film manufacturing method, the organic monomolecular film formed at the interface between water and air can be repeatedly accumulated and accumulated on the solid substrate as many times as desired to produce the thickness of the organic monomolecular film in angstrom units. It is possible to arrange the polymers constituting the organic monomolecular film constantly in a direction perpendicular to the substrate.

However, the conventional LB thin film manufacturing method may arrange the polymers constituting the LB thin film in a direction perpendicular to the substrate, but may not be formed in a direction parallel to the substrate.

Accordingly, the present invention is to provide an improved LB thin film manufacturing apparatus and method for forming a polymer LB thin film closely aligned not only in the direction parallel to the substrate but also in the vertical direction.

It is also an object of the present invention to provide an improved LB thin film manufacturing apparatus and method for forming a polymer LB thin film closely aligned in any constant direction.

The present invention also provides an electrode 4 for applying an electric field in the longitudinal direction and an electrode for applying an electric field in the lateral direction to the barrier 3 of a known LB thin film manufacturing apparatus, An improved LB thin film production apparatus and method for forming an LB thin film capable of more precisely controlling the degree of uniformity of an LB thin film formed by adhesion between thin films.

Another object of the present invention is to improve the LB to form a polymer LB thin film closely aligned in the parallel and vertical direction to the substrate even when the polymer for forming the LB thin film has only hydrophobic groups as well as hydrophilic and hydrophobic groups at the same time It is to provide a thin film manufacturing apparatus and method.

It is still another object of the present invention to provide an improved LB thin film manufacturing apparatus and method which can align the orientation of a polymer deposited on a substrate in any direction other than horizontal or vertical.

In order to achieve the above object, the LB thin film manufacturing apparatus of the present invention includes a main body (2) for containing a mixed solution of water and polymer; A substrate (1) immersed in the water and polymer mixed solution in a direction perpendicular to the surface of the solution; Barriers (3) arranged on the opposite side of the substrate surface in parallel with the substrate surface; It consists of a pair of electrodes 4 formed on the inner wall of the barrier opposite the substrate surface and installed to form a longitudinal electric field, and after applying a voltage to the electrodes 4 provided on the barrier, the barrier ( 3) is gradually approached in the direction of the substrate 1 until just before it becomes a solid phase, and then gradually lifts the substrate in the vertical direction of the surface of the solution while maintaining the surface pressure at that time to align the longitudinal direction on the substrate. The LB thin film is formed into a film.

Hereinafter, the improved LB thin film manufacturing apparatus and method of the present invention will be described with reference to the accompanying drawings. In each figure, the same components used the same reference numerals.

Figure 2 (a) is a schematic configuration of the LB thin film manufacturing apparatus of the present invention is shown. In the LB thin film manufacturing apparatus of the present invention, electrodes 4 are disposed on two barriers 3 for arranging in parallel with the substrate and applying a voltage to generate a longitudinal electric field of the substrate. Further, in order to generate a lateral electric field, a pair of opposing electrodes 5 are provided on the outer surface of the main body 2 of the LB thin film device, respectively, in a direction perpendicular to the substrate surface. When a voltage is applied to the electrodes 4 provided on the two barriers 3, an electric field is generated in the longitudinal direction (that is, the direction perpendicular to the substrate 1), and the polymer has a unique dielectric constant value due to the electric field. 7) is aligned in a constant direction. As the polymer used in the present invention, for example, azobenzene, oligomer (1,4-distyrylnebenzene), porphyrin derivative, phthalocyanine and the like can be used. When a voltage is applied to the polymer, the polymer is aligned in the longitudinal direction (ie, perpendicular to the substrate surface) by an electric field formed between the electrode 4 and the substrate 1. When the barrier 3 is gradually pushed toward the substrate 1, the polymer 7, which was further on the water 6 due to the presence of the hydrophobic group 9, maintains a uniform molecular film in a tight and aligned state by an electric field. . At this time, if the substrate 1 is slowly lifted in the vertical direction, the polymer 7 sticks to the substrate 1 in a state aligned with the electric field, and comes up along with the substrate 1 as shown in FIG. LB thin films aligned in the longitudinal (vertical) direction of the substrate 1 are formed. The polymer 7 may have a hydrophilic group 8 and a hydrophobic group 9 at the same time. In this regard, the hydrophobic group 9 of the polymer has a side chain, as shown in (d) of FIG. 2 or the hydrophobic group 9 is divided into, as shown in (e) of FIG. It may have a symmetrical structure in the magnetic axis direction. When the hydrophobic group (9) has a side branch, the hydrophobic groups themselves of each polymer are also aligned in a certain direction by the electric field, as well as the tail is aligned in a constant direction under the influence of the electric field. In addition, when the hydrophobic group 9 has a symmetrical structure in the molecular direction, the entire hydrophobic group 9 is aligned in a constant direction by the electric field. When the LB thin film thus formed is viewed from the front of the substrate 1, only the hydrophobic group 9 having the tail or the symmetrical structure in the molecular direction will be seen, and thus (c), (c), and (c) of FIG. As shown in (b) of FIG. 3, the LB thin film of the polymer 7 formed on the substrate 1 shows only the hydrophobic group 9 except for the hydrophilic group 8. Even if the polymer (7) does not have a hydrophilic group (8), the polymer (7) is floating on the water (6) due to the presence of the hydrophobic group (9) by the barrier (3) is pushed by the hydrophobic group (9) It is directly attached to the substrate 1, so that the arrangement direction of the polymer 7 on the substrate 1 is determined constant according to the direction of the electric field as described above.

On the other hand, as shown in (a) of FIG. 3, when the voltage is applied in a direction perpendicular to the substrate 1, the voltage is applied to the electrode 5 provided on the outer surface of the main body 2. (1) An electric field in a lateral direction parallel to the surface is generated, and the polymer 7 having an inherent well constant value is aligned in the same direction as the electric field. When the barrier 3 is gradually pushed toward the substrate 1 again, the polymer 7 maintains a uniform monolayer in a dense and aligned state. At this time, if the substrate 1 is gradually lifted in the vertical direction, the polymers 7 It adheres to the substrate 1 in a state aligned in a constant direction and comes up together to form an LB thin film aligned in the transverse (horizontal) direction with respect to the substrate 1 as shown in FIG. The polymer (7) may have a hydrophobic group (9) and a hydrophilic group (8) at the same time, or have only a hydrophobic group (9), or may be longitudinally or transversely aligned as described above with reference to FIG. 2 or 3. An LB thin film of the polymer 7 is formed.

2 (a) and 3 (a) illustrate only a pair of electrodes 4 and 5 arranged only in the longitudinal or transverse direction with respect to the substrate 1, respectively. Can be installed at a predetermined angle with respect to the substrate, and the orientation of the polymer 7 deposited on the substrate 1 can be arbitrarily controlled by arbitrarily adjusting the selection angle.

Therefore, even in the case of a conductive polymer, the conductive polymer may be oriented in a predetermined direction on the substrate by the LB thin film manufacturing apparatus and method of the present invention.

The present invention has been described in detail above. However, various modifications and changes may be made by those skilled in the art without departing from the scope of the present invention. Therefore, the present invention is not limited only to the above-described embodiments or drawings, but only by the claims.

Claims (10)

A main body 2 for containing a mixed solution of water and a polymer; A substrate (1) immersed in the water and polymer mixed solution in a direction perpendicular to the surface of the solution; A barrier (3) arranged on a side opposite to the substrate surface in a direction parallel to the substrate surface; A pair of electrodes 4 formed on the inner wall of the barrier opposite the substrate surface and installed to form a longitudinal electric field and applying a voltage to the electrodes 4 provided on the barrier, the barrier 3 ) Gradually approaching the substrate 1 direction, and then slowly lifting the substrate in the vertical direction of the solution surface to form an LB thin film vertically aligned on the substrate. Manufacturing device. The apparatus of claim 1, wherein the LB thin film manufacturing apparatus applying the electric field further includes a pair of electrodes 5 arranged on an outer sidewall of the main body in a direction perpendicular to the surface of the substrate to form a transverse electric field. LB thin film manufacturing apparatus is applied to the electric field, characterized in that the LB thin film arranged in the longitudinal and transverse direction is formed on the substrate. The electric field is applied according to claim 1, wherein the arrangement direction of the electrode 4 is provided in a direction having an angle on the surface of the substrate so that the orientation of the polymer deposited on the substrate can be arbitrarily controlled. One LB thin film manufacturing apparatus. A main body 2 for containing a mixed solution of water and a polymer; A substrate (1) immersed in the water and polymer mixed solution in a direction perpendicular to the surface of the solution; A barrier (3) arranged on a side opposite to the substrate surface in a direction parallel to the substrate surface; A pair of electrodes 5 arranged on an outer sidewall of the body in a direction perpendicular to the substrate surface to form a lateral electric field, applying a voltage to the electrodes 5, and applying the barrier 3 to the Apparatus for applying LB thin film to an electric field, characterized in that after gradually approaching the substrate 1 direction, the substrate is gradually lifted in the vertical direction of the surface of the solution to form a horizontally aligned LB thin film on the substrate. . The method according to claim 4, wherein the arrangement direction of the electrode 5 is provided in a direction having an arbitrary angle on the surface of the substrate, so that the direction of the polymer deposited on the substrate can be arbitrarily controlled. The LB thin film manufacturing apparatus which applied the electric field to make. Placing a mixed solution of water and a polymer in the main body 2; Immersing the substrate (1) in the water and polymer mixed solution in a direction perpendicular to the surface of the solution; Arranging a barrier (3) on a side opposite to the substrate surface in a direction parallel to the substrate surface; Installing a pair of electrodes (4) formed on an inner wall of the barrier opposite the substrate surface to form a longitudinal electric field; Applying a voltage to an electrode (4) provided at the barrier; Gradually approaching the barrier (3) in the direction of the substrate (1); And gradually lifting the substrate in a vertical direction of the surface of the solution, wherein a longitudinally aligned LB thin film is formed on the substrate to produce an LB thin film. 7. The method according to claim 6, wherein the method for producing an LB thin film by applying the electric field comprises the step of installing the pair of electrodes 4, followed by an external sidewall of the body in a direction perpendicular to the substrate surface to form a transverse electric field. A method of manufacturing an LB thin film by applying an electric field, characterized in that it further comprises the step of installing a pair of electrodes (5) on the substrate, the LB thin film aligned in the longitudinal and transverse directions. In the step of installing the electrode 4 of claim 6, the arrangement direction of the electrode 4 is arranged in a direction having an arbitrary angle on the surface of the substrate, thereby arbitrarily controlling the orientation of the polymer deposited on the substrate. Method for producing an LB thin film by applying an electric field characterized in that it can be done. Placing the mixed solution of water and polymer in the main body (2); Immersing the substrate (1) in the water and polymer mixed solution in a direction perpendicular to the surface of the solution; Arranging a barrier (3) on a side opposite to the substrate surface in a direction parallel to the substrate surface; Installing a pair of electrodes (5) on an outer sidewall of the body in a direction perpendicular to the substrate surface to form a transverse electric field; Applying a voltage to an electrode (5) provided on an outer sidewall of the body; Gradually approaching the barrier (3) in the direction of the substrate (1); And gradually lifting the substrate in a vertical direction of the surface of the solution, wherein a horizontally aligned LB thin film is formed on the substrate to produce an LB thin film. In the step of installing the electrode (5) of claim 9, the arrangement direction of the electrode (5) is provided in a direction having an arbitrary angle on the surface of the substrate, so that the orientation of the polymer deposited on the substrate is arbitrarily selected. Method for producing an LB thin film by applying an electric field characterized in that it can be controlled.