KR20190054521A - Method for manufacturing three-dimensional laminated structure and three-dimensional laminated structure manufactured thereby - Google Patents

Abstract

The present invention relates to a manufacturing method of a three-dimensional stacked structure and the three-dimensional stacked structure manufactured by the same. According to an embodiment of the present invention, the manufacturing method of the three-dimensional stacked structure includes: a step (a) of forming a first block layer including at least one functional layer; a step (b) of transferring the first block layer on a substrate; a step (c) of forming a quantum dot layer including quantum dots of a core-shell structure in at least one part on the first block layer; a step (d) of forming a second block layer including at least one functional layer; and a step (e) of stacking the second block layer on the quantum dot layer. The present invention is provided to improve the electrical characteristics of the stacked structure.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a method of manufacturing a three-dimensional laminated structure, and a three-dimensional laminated structure produced by the method.

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of manufacturing a three-dimensional laminated structure and a three-dimensional laminated structure produced thereby, and more particularly, to a three-dimensional laminated structure produced by laminating a material layer of a two-dimensional structure and quantum dots of a non-

2D transition metal dichalcogenides have recently attracted a great deal of attention due to their excellent photoelectric properties associated with a two dimensional confined chemical structure unique to an insulator, direct bandgap semiconductor to metal.

In recent years, studies have been made on the fabrication of transistors with a new structure by laminating two-dimensional transition metal decalcogenide materials having different electrical characteristics and observing the electrical characteristics thereof. In addition, by using the WS ₂ and MoS ₂ the chemical vapor deposition (CVD) is grown directly on a silicon (Si) substrate was made a hetero-junction triggered active research on evaluation new material properties, WS ₂ / MoS ₂ or WSe _{- 2} / MoS ₂ structure has been reported several times for application to optoelectronic devices such as solar cell and photodetector. 2. Description of the Related Art [0002] Research has been actively conducted on various application fields using a two-dimensional transition metal dicalcogenide material having various electrical characteristics, and attention has been paid to effectively stacking such structures.

There has been a problem in forming a material layer having a uniform two-dimensional structure in accordance with the surface characteristics of the target substrate when the conventional two-dimensional structure material layer is formed by chemical vapor deposition. In particular, when a non-dimensional quantum dot layer is formed between two-dimensional structure material layers, it is difficult to form a uniform surface layer because the surface is not smooth when stacking additional material layers by chemical vapor deposition, The characteristics of the quantum dots may be changed.

SUMMARY OF THE INVENTION Accordingly, the present invention has been made to solve the above-mentioned problems and it is an object of the present invention to provide a method for effectively stacking a two-dimensional structure material layer and a zero-dimensional quantum dot.

It is another object of the present invention to effectively protect quantum dots by stacking multi-layered material layers of quantum dots and two-dimensional structures, and to improve the electrical characteristics of a multilayer structure used in optoelectronic devices.

However, these problems are exemplary and do not limit the scope of the present invention.

According to an aspect of the present invention, there is provided a method of manufacturing a semiconductor device, comprising: (a) forming a first block layer including at least one functional layer; (b) (C) forming a quantum dot layer including quantum dots of a core-shell structure on at least a part of the first block layer; (d) forming a second block layer including at least one functional layer And (e) laminating the second block layer on the quantum dot layer.

According to an embodiment of the present invention, the method may further include the step of laminating the quantum dot layer and the first block layer or the second block layer on the second block layer.

According to an embodiment of the present invention, the step (a) includes the steps of (a1) forming a first functional layer on a metal plate layer, (a2) (A3) removing the metal plate layer, and (a4) removing the carrier polymer layer.

According to an embodiment of the present invention, there is provided a method of manufacturing a semiconductor device, comprising the steps of: (a3) forming a second functional layer on a metal plate layer; (a6) And (a7) removing the metal plate layer.

According to an embodiment of the present invention, the step (d) includes the steps of (d1) forming the third functional layer on the metal plate layer, (d2) forming a carrier polymer layer on the third functional layer, (D3) removing the metal plate layer, and (d4) removing the carrier polymer layer.

According to an embodiment of the present invention, there is provided a method of manufacturing a semiconductor device, comprising the steps of: (d3) forming a fourth functional layer on a metal plate layer; (d6) The step of transferring the carrier polymer layer, and (d7) the step of removing the metal plate layer.

According to an embodiment of the present invention, the functional layer may be formed by a chemical vapor deposition method using a functional material precursor.

According to an embodiment of the present invention, the functional layer may be any one selected from the group consisting of graphene, h-BN, WSe _2, and MoS ₂ .

According to an embodiment of the present invention, the quantum dot layer may be formed by spin coating quantum dots of the core-shell structure.

According to an embodiment of the present invention, the quantum dot of the core-shell structure may be any one selected from the group consisting of CdSe, CdTe, CdS, InP, ZnCdSe, PbS, PbSe, CGS, CIGS and CIS , And the shell may be any one selected from the group consisting of ZnS, CdS, and ZnSe.

According to an embodiment of the present invention, the substrate may include silicon and silicon oxide.

According to an aspect of the present invention for solving the above problems, there is provided a three-dimensional laminated structure manufactured by the above-described manufacturing method.

According to one embodiment of the present invention as described above, it is possible to provide a method of fabricating a three-dimensional stacked structure that effectively stacks a two-dimensional structure material layer and a zero-dimensional quantum dot.

Further, according to the present invention, there is an effect that the quantum dots are effectively laminated by stacking multi-layered quantum dots and two-dimensional material layers by the above-described manufacturing method, and electrical characteristics of the three-dimensional stacked structure used in the optoelectronic devices are improved.

Of course, the scope of the present invention is not limited by these effects.

1 is a flowchart showing a method of manufacturing a three-dimensional laminated structure according to an embodiment of the present invention.
2 is a cross-sectional view illustrating a three-dimensional laminated structure according to an embodiment of the present invention.
3 is a schematic view showing a method of forming a functional layer according to an embodiment of the present invention.
4 is a schematic view showing a method of forming a block layer by stacking functional layers according to an embodiment of the present invention.
5 is a schematic diagram illustrating a method of fabricating a three-dimensional stacked structure including a graphene, an h-BN functional layer, and a CdSe-ZnS quantum dot according to an embodiment of the present invention.
6 is a schematic view showing a three-dimensional stacked structure including a graphene, an h-BN functional layer, and a CdSe-ZnS quantum dot according to an embodiment of the present invention.
FIG. 7 is a transmission electron microscope photograph showing a cross section of a three-dimensional laminated structure including a graphene, an h-BN functional layer and a CdSe-ZnS quantum dot according to an embodiment of the present invention.
8 and 9 are graphs showing line profile results of a three-dimensional laminated structure according to an embodiment of the present invention.
10 is a graph showing the results of experiments for measuring photoluminescence intensity of quantum dots according to one example of the present invention and one comparative example.
11 is a schematic diagram showing an application example of an optoelectronic device including a three-dimensional laminate structure 10 according to an embodiment of the present invention.

The following detailed description of the invention refers to the accompanying drawings, which illustrate, by way of illustration, specific embodiments in which the invention may be practiced. These embodiments are described in sufficient detail to enable those skilled in the art to practice the invention. It should be understood that the various embodiments of the present invention are different, but need not be mutually exclusive. For example, certain features, structures, and characteristics described herein may be implemented in other embodiments without departing from the spirit and scope of the invention in connection with an embodiment. It is also to be understood that the position or arrangement of the individual components within each disclosed embodiment may be varied without departing from the spirit and scope of the invention. The following detailed description is, therefore, not to be taken in a limiting sense, and the scope of the present invention is to be limited only by the appended claims, along with the full scope of equivalents to which such claims are entitled, if properly explained. In the drawings, like reference numerals refer to the same or similar functions throughout the several views, and length and area, thickness, and the like may be exaggerated for convenience.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings, so that those skilled in the art can easily carry out the present invention.

A method of manufacturing the three-dimensional laminated structure 10 according to an embodiment of the present invention will be described with reference to FIGS. 1 and 2. FIG.

FIG. 1 is a flowchart showing a method of manufacturing a three-dimensional laminated structure 10 according to an embodiment of the present invention, and FIG. 2 is a sectional view showing a three-dimensional laminated structure 10 according to an embodiment of the present invention.

According to an embodiment of the present invention, the three-dimensional laminated structure 10 includes the steps of: (a) forming a first block layer 100 including at least one functional layer (S10); (b) (S20) of transferring the layer 100 onto the substrate 50, (c) forming a quantum dot layer 310 including the quantum dot 310 of the core-shell structure on at least a part of the first block layer 100 (D) forming a second blocking layer 200 including at least one functional layer (S40); and (e) forming a second blocking layer on the quantum dot layer 300 (Step S50).

The three-dimensional laminated structure 10 may include a functional layer having excellent electrical characteristics and a quantum dot 310 capable of absorbing external energy, and the three-dimensional laminated structure 10 may be effectively applied to an optical device. On the other hand, the functional layer of the present invention may be a conductive layer having a high energy conductivity, and may be an insulating layer having excellent insulating properties and a semiconductor functional layer having a bandgap. However, the present invention is not limited thereto.

The first block layer 100 may form a structure in which at least one functional layer is stacked. The functional layer has a two-dimensional structure and can be formed in a flat shape or a sheet shape. The first block layer 100 may have one or more functional layers stacked thereon, which can be appropriately adjusted according to the use of the three-dimensional laminated structure 10. The second block layer 200 is a block layer having a structure similar to that of the first block layer 100 but differentiated from each other in the three-dimensional laminate structure 10. [ The first block layer 100 refers to a layer formed on the lowermost substrate 50 in the three-dimensional laminate structure 10 while the second block layer 200 refers to a layer formed on the lowermost substrate 50 in the three- Or one or more layers may be formed to form the uppermost layer. The first block layer 100 and the second block layer 200 are block layers that are separated from each other, but have at least one functional layer and have a similar structure and effect. That is, in the three-dimensional laminate structure 10, the first block layer 100 and the second block layer 200 may have the same effect by stacking one or more layers. However, a block layer to be transferred onto the lowermost substrate 50 is defined as a first block layer 100.

The three-dimensional stacked structure 10 may include a first block layer 100, a quantum dot layer 300 and a second block layer 200 which are sequentially stacked on the second block layer 200 formed on the top, The layer 300 and the second block layer 200 may be alternately stacked. According to an embodiment of the present invention, a method of manufacturing a three-dimensional laminated structure 10 includes the steps of forming a quantum dot layer 300 and a first block layer 100 or a second block layer 200 ) May be further stacked. This can be controlled by repeating the same process as needed during the manufacturing process. When a plurality of quantum dot layers 300 including quantum dots 310 having external energy absorbing characteristics are required, the first and second block layers 100 and 200 are alternately stacked to form a three-dimensional A multi-layered structure can be formed in the laminated structure 10.

Particularly, when the quantum dot layer 300 is formed and the second block layer 200 is stacked, it can be safely and effectively stacked using a building block method. When a quantum dot layer 300 is formed and then a block layer including a functional layer is laminated on the quantum dot layer 300, the method of directly laminating may affect the surface characteristics of the quantum dot 310. On the other hand, if the block layer separately manufactured using the building block method is laminated by a method of transferring on the quantum dot layer 300, the quantum dot 310 can be safely stacked without affecting the surface of the quantum dot 310, And the functional layer of the separately produced block layer can have a uniform surface.

FIG. 3 is a schematic view showing a method of forming a functional layer according to an embodiment of the present invention, and FIG. 4 is a schematic diagram showing a method of forming a functional layer by stacking functional layers according to an embodiment of the present invention.

Referring to FIG. 3, according to one embodiment of the present invention, the functional layer may be formed by chemical vapor deposition (CVD) using a functional material precursor.

In the case of the conventional Scotch tape method for manufacturing a material layer of a two-dimensional structure, there is a disadvantage in that mass production can not be achieved by a method of directly peeling each layer using a scotch tape. On the other hand, chemical vapor deposition (CVD) is a method of depositing a precursor material in a gaseous state on a substrate to form a material layer of a two-dimensional structure, which can be mass-produced and synthesized in a large area, .

According to an embodiment of the present invention, in the step of forming the first block layer 100, step (a) includes the steps of (a1) forming a first functional layer 110 on the metal foil layer 500 (A2) forming a carrier polymer layer 510 on the first functional layer 110, (a3) removing the metal plate layer 500, and (a4) removing the carrier polymer layer 510 ). ≪ / RTI > After step (a3), (a5) forming the second functional layer 120 on the metal plate layer 500, (a6) forming the first functional layer 110 and the carrier polymer layer 120 on the second functional layer, (A7) removing the metal plate layer 500, as shown in FIG.

According to an embodiment of the present invention, in the step of forming the second block layer 200, (d) includes the steps of (d1) forming a third functional layer 230 on the metal plate layer 500 (D2) forming a carrier polymer layer 510 on the third functional layer 230, (d3) removing the metal plate layer 500, and (d4) removing the carrier polymer layer 510 Step < / RTI > (D5) forming a fourth functional layer 240 on the metal plate layer 500, (d6) forming a third functional layer 230 on the fourth functional layer 240, Transferring the carrier polymer layer 510, and (d7) removing the metal plate layer 500.

When a functional material is laminated by chemical vapor deposition, it is affected when a functional material is formed depending on the surface characteristics of the substrate on which the deposition is performed. And, the functional material formed in the previous step may change shape or crack in the temperature and pressure environment in the chamber where the chemical vapor deposition process is performed. In order to prevent such problems, the functional materials formed by the chemical vapor deposition method can be effectively stacked by using the building block method.

First, in step (a1), a first functional layer 110 is formed on a metal plate layer 500 by chemical vapor deposition. At this time, the metal plate layer 500 is not limited to the type, but preferably a copper plate or an iron plate can be used, or a metal foil including copper or iron. When the first functional layer 110 is formed through chemical vapor deposition, a desired functional layer can be formed by controlling the kind of precursor, temperature, pressure, and time.

Meanwhile, according to one embodiment of the present invention, the functional layer may be any one selected from the group consisting of graphene, h-BN, WSe _2, and MoS ₂ .

Graphene and h-BN have a hexagonal planar structure, and WSe ₂ and MoS ₂ have a planar structure as a two-dimensional transition metal dicalcogenide material. All of these materials are excellent in electric characteristics and can be used in optical devices or electric devices. The three-dimensional laminated structure 10 can be manufactured by selecting a functional material according to needs of the product to be used.

Next, in step (a2), a carrier polymer layer 510 is formed on the first functional layer 110. Preferably, the carrier polymer layer 510 may comprise poly (methyl methacrylate) (PMMA). The carrier polymer layer 510 protects and protects the first functional layer 110 during its transfer. Even when the metal plate is removed, the first functional layer 110 formed by the functional material can maintain a two-dimensional structure.

In step (a3), the metal plate layer 500 is etched and removed to produce the first functional layer 110 having the carrier polymer layer 510 formed thereon. If only the functional layer and the carrier polymer layer 510 are formed, the step of transferring and stacking the functional layer and the carrier polymer layer 510 on other functional layers can be performed safely and effectively. In step (a4), the first block layer 100 including the first functional layer 110 may be formed by removing the carrier polymer layer 510. [

On the other hand, since the first block layer 100 includes at least one functional layer, the functional layer may be one or more layers. According to an embodiment of the present invention, after step (a3), a second functional layer 120 is formed on the metal plate layer 500, and (a6) a second functional layer 120 is formed on the metal plate layer 500, (A7) removing the metal plate layer 500, so that the first block layer 100 has at least one functional layer, and at least one functional layer is formed on the first functional layer 110 and the carrier polymer layer 510, A laminated structure can be formed. At this time, (a4) the step of removing the carrier polymer layer 510 may be performed to form the first block layer 100 in which [the second functional layer 120 / the first functional layer 110] is formed have.

(The fourth functional layer 240 / the third functional layer 230) is the same as the above method (the steps (a1) to (a7) correspond to the steps d1) to d7) The second block layer 200 can be formed. Since the first functional layer 110 to the fourth functional layer 240 are formed in the same manner and in the same structure but are stacked in the first and second block layers 100 and 200, Layer. According to an embodiment of the present invention, the first functional layer 110 to the fourth functional layer 240 may include the same type of functional material or different types of functional materials. The present invention is not limited thereto.

When the first block layer 100 and the second block layer 200 are formed through the above-described method, it is possible to form a uniform functional layer over the functional layer by a direct chemical vapor deposition method, It is possible to prevent the functional layer from being damaged. Particularly, since the first block layer 100 and the second block layer 200 are formed in a block shape and can be stacked by the building block method, the quantum dot layer 300 included in the three- When the first block layer 100 or the second block layer 200 is transferred and laminated, the characteristics and shape of the quantum dot 310 can be safely maintained.

According to an embodiment of the present invention, the quantum dot 310 of the core-shell structure may be formed of any one selected from the group consisting of CdSe, CdTe, CdS, InP, ZnCdSe, PbS, PbSe, CGS, CIGS and CIS And the shell may be any one selected from the group consisting of ZnS, CdS, and ZnSe.

The quantum dot 310 may have high light emission and energy absorption rate. Dimensional laminate structure 10 used for an electric device to absorb energy and transmit energy to the functional layers formed on the upper and lower sides to realize excellent electrical characteristics of the three-dimensional laminate structure 10. [

According to an embodiment of the present invention, the quantum dot layer 300 may be formed by spin coating the quantum dot 310 of the core-shell structure.

It is possible to form the quantum dot layer 300 by removing the carrier polymer layer on the first block layer 100 or the second block layer 200 by using a commonly used spin coater and spin coating the quantum dot 310 have.

According to an embodiment of the present invention, the substrate 50 may include silicon and silicon oxide. The substrate 50 may be a substrate of a type commonly used in electrical devices. A substrate used for a transistor, a photocatalyst, a memory, and the like includes silicon and silicon oxide, and the three-dimensional laminate structure 10 of the present invention can also be manufactured using the substrate 50 as a base.

Referring to FIG. 2, the three-dimensional laminate structure 10 forms the lowermost portion of the substrate 50 including silicon and silicon oxide. A first block layer 100 including one layer of the first functional layer 110 and one layer of the second functional layer 120 is formed on the substrate 50. The first block layer 100 may include one or more functional layers. Preferably, the first functional layer 110 and the second functional layer 120 may be included one by one.

The quantum dot layer 300 and the second block layer 200 are alternately formed on the first block layer 100. 2, the quantum dot layer 300 and the second block layer 200 are each formed of two layers, but the present invention is not limited thereto. Since the quantum dot layer 300 has the functional layers sandwiched between the upper and lower portions, the energy absorbed by the quantum dot 310 can be effectively transmitted. In addition, since a block layer is formed by a method of forming and transferring a block layer instead of forming a functional layer directly by chemical vapor deposition on the quantum dot 310, it is possible to form a laminate structure safely on the quantum dot 310 Do.

The second block layer 200 may include at least one functional layer. Preferably, the third functional layer 230 and the fourth functional layer 240 may be alternately formed. The quantum dot layer 300 is not formed on the second block layer 200 formed on the top of the three-dimensionally stacked structure 10. On the other hand, in the second block layer 200 formed on the intermediate layer, the carrier polymer layer is removed and the quantum dot 310 is spin-coated to form the quantum dot layer 300, and a second block layer 200 is formed thereon So that a multilayer laminated structure can be formed.

Hereinafter, a three-dimensional laminated structure using graphene and h-BN according to an embodiment of the present invention will be described with reference to FIGS. 5 to 10. FIG.

FIG. 5 is a schematic view showing a method of fabricating a three-dimensional stacked structure including a graphene, an h-BN functional layer and a CdSe-ZnS quantum dot according to an embodiment of the present invention. A h-BN functional layer and a CdSe-ZnS quantum dot according to the present invention.

Example 1: Preparation of a graphene functional layer by a chemical vapor deposition (CVD) method

A method of manufacturing a first functional layer including a graphene according to an embodiment of the present invention will be described. The catalyst used was Cu (35 nm) and methane (CH ₄ ) as a precursor. First, copper foil used as a substrate on which graphene is formed is washed in the order of acetone, isopropyl alcohol (IPA), and ethanol (Ethanol). Then, Cu foil is loaded on a 2 inch quartz tube where chemical vapor deposition is performed. H ₂ gas is supplied to the quartz tube at 100 sccm and annealing is performed for 90 minutes. Thereafter, 100 sccm of H ₂ gas and 5 sccm of CH ₄ gas are supplied for 1 minute. Then, 100 sccm of H ₂ gas and 13 sccm of CH ₄ gas were supplied for 8 minutes to grow a functional layer containing graphene. After 8 minutes, the quartz tube is opened and cooled to 15 sccm of H2 gas until the temperature of the copper foil falls below 200 ° C. Through the above method, a first functional layer having graphene formed on a copper foil is produced.

Example 2: Preparation of h-BN (Hexagonal boron nitride) functional layer by chemical vapor deposition (CVD)

Next, a method for manufacturing a second functional layer including h-BN (hexagonal boron nitride) according to an embodiment of the present invention will be described.

First, an iron foil used as a base on which h-BN is formed was cut into a size of 2 cm x 10 cm and used. As the precursor of h-BN, borazine ((BH) 3 (NH) 3) was used. It is desirable to maintain the temperature at 10 ° C so that the vapor pressure remains constant without being affected by the temperature. At sub-zero temperature, the gaseous phase is not well vaporized, so gaseous diluted burezine can be used as a precursor by adding hydrogen and connecting the tube to a liquid-state borazine. The gaseous borazine precursor is advantageous in that it is easier to control the flow rate and does not generate solid impurities than the solid precursor.

To prepare the second functional layer having h-BN, iron foil was treated with acetone, isopropanol and ethanol to remove organic impurities and washed with distilled water. First, the inside of the CVD chamber prior to heating the iron foil enough dry pump 1 hours ^vacuum-made (1 x 10 ⁴ Torr or less) to eliminate the outside air particles and water, the flow rate of 100sccm for H ₂ gas at a pressure of 1Torr state . The iron foil in the CVD chamber was then heated from room temperature to 1,100 ° C over 30 minutes, and when the temperature reached 1,100 ° C, it was held at 1,100 ° C for 30 minutes for thermal stabilization. At a temperature of 1,100 ° C, the iron foil becomes more soluble in nitrogen and boron than at room temperature. Under these conditions, the precursor of h-BN, which is a precursor of borazine gas, is 0.15 sccm, the carrier gas is H ₂ The gas was supplied at 100 sccm to allow the precursor to dissolve into the iron foil for 1 hour. The iron foil in which the precursor of h-BN is dissolved is then cooled down to 700 ° C at a rate of 5 ° C / min. In this cooling process, a second functional layer having h-BN formed on the iron foil is prepared from borazine, which is an h-BN precursor dissolved in an iron foil.

Example 3 Preparation of MoS ₂ Functional Layer by Chemical Vapor Deposition (CVD)

Next, a method for manufacturing a functional layer including MoS ₂ according to an embodiment of the present invention will be described. First, the SiO ₂ / Si substrate washed with acetone and IPA is poured into a chamber having a purity of 99.999% argon (Ar) gas atmosphere. The high-purity MoO ₃ (99.5%) and sulfur powder (99.5%) were placed in a furnace and placed in a furnace. Subsequently, the furnace was purged with argon (150 sccm) at 650 ° C for 30 minutes To prepare an MoS ₂ functional layer.

Example 4 Preparation of WSe ₂ Functional Layer by Chemical Vapor Deposition (CVD) Method

Next, a method of manufacturing a functional layer including WSe ₂ according to an embodiment of the present invention will be described. First, the SiO ₂ / Si substrate washed with acetone and IPA is poured into a chamber having a purity of 99.999% argon (Ar) gas atmosphere. High purity MoO ₃ (99.5%) and Sulfur powder (99.5%) were placed in a quartz boat, placed in a chamber, and then injected at an atmospheric pressure of 650 sccm for 30 minutes in an amount of 150 sccm. MoS ₂ functional layer.

Place the SiO ₂ / Si substrate washed with acetone and IPA in the chamber, and place 0.3 g of WO ₃ and Se powder in a ceramic boat divided into two chambers. And reacted at 270 ° C. Thereafter, the carrier gas is maintained at 80 sccm of argon and the pressure of 20 sccm of hydrogen at 1 Torr, reacted at 925 ° C for 15 minutes, and then cooled to room temperature to form a WSe ₂ functional layer.

Example 5: Preparation of CdSe-ZnS quantum dots

Next, a CdSe-ZnS quantum dot manufacturing method according to an embodiment of the present invention will be described. Trioctylamine (TOA), oleic acid (OA), and cadmium oxide were placed in a 125 ml flask equipped with a reflux condenser and stirred at 300 ° C and 700 rpm to prepare a mixture. Separately, a Se-TOP complex solution is prepared by dissolving Se powder in 97% purity trioctylphosphine (TOP). The Se-TOP complex solution is injected at a high rate into the stirred mixture at 300 ° C to react. During the reaction, a constant stirring speed was maintained in a nitrogen atmosphere. CdSe cores are prepared by the above method, and ZnMe ₂ and (TMS) ₂ S are injected to prepare quantum dots having a CdSe core and a ZnS shell. The quantum dot nanoparticles are dissolved in 15 mL of hexane and purified. 15 mL of a mixed solution of CHCl ₃ and CH ₃ OH in a volume ratio of 1: 1 was added to a hexane solution containing nanoparticles to extract quantum dots. Only the upper layer was separated because pure Qd nanoparticles were dissolved in the upper layer of the mixed solution. The separated upper layer solution is centrifuged using acetone. When the quantum dots formed were green, the reaction was carried out at 140 ° C for 30 minutes. The reaction was carried out at 240 ° C for 30 minutes for red and at 120 ° C for 10 minutes for blue to obtain nanoparticles.

Example 6: Method for producing a three-dimensional laminated structure using a building block method

A method of fabricating a three-dimensional laminated structure according to an embodiment of the present invention will be described with reference to FIGS. 5 and 6, using the functional layer manufactured in the first and second embodiments and the quantum dot prepared in the fifth embodiment .

(1) Production of first block layer

First, polymethyl methacrylate (PMMA) was coated on the first functional layer including the graphene of Example 1, and the copper foil was removed by etching the copper (Cu etchant) Pin / PMMA] layer is formed. Then, a [graphene / PMMA] layer is transferred onto the second functional layer including h-BN in the second embodiment. The first block layer having the PMMA layer of [h-BN / graphene / PMMA] layer was prepared by removing Cu (Fe) in the same manner and transferred to a silicon substrate to produce [Silicon / silicon dioxide / BN / graphene / PMMA] layer. Thereafter, it is immersed in acetone for 1 hour, followed by washing with distilled water for 20 minutes, followed by drying in a 60 ° oven to remove PMMA. The CdSe-ZnS quantum dots of Example 3 dispersed in toluene at a concentration of 2 wt% were coated with a spin coater at 3000 rpm for 40 seconds, and heat treatment was performed at 110 DEG C for 10 minutes. Silicon / Silicon dioxide / h-BN / graphene / CdSe-ZnS quantum dot structure is formed through the above process.

(2) Production of second block layer

Next, except for the step of (1) the step of transferring to the silicon substrate in the production of the first block layer and the step of spin-coating the CdSe-ZnS quantum dot [h-BN / graphene / PMMA ] Layer, which is then transferred onto the graphene functional layer of Example 1 to remove Cu. Through the above process, a second block layer having PMMA having a structure of [graphene / h-BN / graphene / PMMA] is prepared.

(3) Production of a three-dimensional laminated structure

Next, the second block layer is transferred to the first block layer and the CdSe-ZnS quantum dots are coated by the same method as described in (1) the first block layer. Then, another second block layer is manufactured, and the second block layer is transferred and the PMMA is removed. As shown in FIG. 6, the three-dimensional laminated structure according to an embodiment of the present invention can be manufactured.

Example 7: Analysis of composition of three-dimensional laminated structure

A transmission electron microscope was used for structural analysis of the three-dimensional laminated structure manufactured in Example 6 above. FIG. 7 is a transmission electron microscope (SEM) image showing a cross-section of a three-dimensional laminated structure including graphene, an h-BN functional layer, and a CdSe-ZnS quantum dot according to an embodiment of the present invention.

According to FIG. 7, graphene and h-BN are stacked on each other and a CdSe-ZnS quantum dot is formed therebetween. For accurate qualitative analysis of the structure, line profiles were used to determine what constituents were present in each layer.

 8 and 9 are graphs showing line profile results of a three-dimensional laminated structure according to an embodiment of the present invention.

In the three-dimensional laminate structure including the graphene, the h-BN functional layer and the CdSe-ZnS quantum dots according to an embodiment of the present invention, the component analysis according to the position based on the lower part where the silicon substrate is formed Respectively.

8 (a), in the transmission electron microscope photograph of the three-dimensional laminated structure, a spherical dark region corresponds to a CdSe-ZnS quantum dot, and a region where a linear stripe is formed around the spherical dark region corresponds to graphene and h- It corresponds to the functional layer of BN. The functional layer formed by the chemical vapor deposition method is laminated to a thin thickness and the CdSe-ZnS quantum dot is coated thereon. The second block layer including the functional layer and the quantum dot layer may be repeatedly laminated on at least one layer. The PMMA is removed from the uppermost layer of the three-dimensional laminated structure, and only the functional layer can be formed without coating the quantum dots.

8 (b) is a graph showing energy dispersive X-ray spectroscopy (EDS) results according to the position of the three-dimensional laminated structure according to an embodiment of the present invention. In order to selectively analyze the CdSe-ZnS quantum dots, the intensity of the X-ray signal emitted from the quantum dots using the EDS is represented by counts. In FIG. 8 (b), the two regions where the number of counts, i.e., the number of counts, which is the strength of the signal, are high refers to a layer in which CdSe-ZnS quantum dots are formed. The quantum dots 310 have an average size of about 2 nm to 10 nm, forming a single layer in the three-dimensional laminate structure 10. That is, as shown in FIG. 6 (b), the thickness of the quantum dot layer 300 is on the average of 5 nm to 7 nm, and it is found that the thickness is very thin. The number of counts around the layer where the quantum dots are formed is low, which means that graphene and h-BN functional layers are formed.

The functional layer of the two-dimensional structure forms an extremely thin layer having an average thickness of about 0.5 nm. In FIG. 8 (b), the number of counts, which is the intensity of a signal, appears in the form of a peak. The interval between peaks is about 0.5 nm, which is formed at the upper and lower portions of the quantum dots, it means.

FIG. 9A is a transmission electron microscope photograph showing a cross section of a three-dimensional laminated structure according to an embodiment of the present invention, FIG. 9B is a line profile showing component analysis according to a region of the three- Graph.

9 (b), the number of Cd, Se, S, N, C and B elements contained in the graphene, h-BN functional layer and CdSe-ZnS according to the position of the laminated structure . The number of counts of C, B and N elements is high in a region with a position of 10 nm to 11 nm, a region of 20 to 21 nm, and a region of 28 to 29 nm. This means that a [graphene / h-BN / graphene] layer included in the first block layer and the second block layer in the three-dimensional stacked structure is formed.

On the other hand, the number of counts of Cd, Se and S elements is high in the region of 15 to 17 nm in height and in the region of 25 to 27 nm, which means a layer in which CdSe-ZnS quantum dots are formed in the three-dimensional laminated structure. This is because the three-dimensional laminated structure according to an embodiment of the present invention can form a thin layer by forming a functional layer using a chemical vapor deposition method, spin-coating the quantum dot on the upper layer, and then transferring the layer. It is possible to effectively stack two-dimensional and zero-dimensional structure material layers without intermixing or partial defects.

EXPERIMENTAL EXAMPLE 1: Analysis of physical properties of a three-dimensional laminated structure

Next, physical property analysis of the three-dimensional laminated structure according to an experimental example of the present invention will be described with reference to FIG.

10 is a graph showing the results of experiments for measuring photoluminescence intensity of quantum dots according to one example of the present invention and one comparative example. When the quantum dots were irradiated with light and absorbed energy, the energy transferred by the graphene or h-BN functional layer was measured.

The photoluminescence intensity was measured by preparing a [CdSe-ZnS] layer and a [graphene / CdSe-ZnS] layer as one comparative example and a [graphene / CdSe-ZnS / Was measured. 10 (a) is a schematic view showing a three-dimensional laminated structure in which graphene and CdSe-ZnS quantum dots are stacked according to one embodiment of the present invention and one comparative example, and FIG. 10 (b) Of the present invention.

Referring to FIG. 10 (b), in the case of a [graphene / CdSe-ZnS] layer having a graphene layer having a high energy transfer ability in only one direction, 52% And the photoluminescence intensity is reduced by 52% by quenching. On the other hand, in the case of the [graphene / CdSe-ZnS / graphene] layer in which graphene layers were formed in both directions, the energy absorbed by the quantum dots in both directions was transmitted and showed an energy reduction of 81%.

In addition, the same experiment was performed using the h-BN functional layer and the CdSe-ZnS quantum dot having strong insulating properties. As a comparative example, a [h-BN / CdSe-ZnS / graphene] layer was prepared as one example of a [CdSe-ZnS] layer and an [h-BN / CdSe-ZnS] Respectively. 8 (c) is a schematic view showing a laminated structure in which graphene, an h-BN functional layer and a CdSe-ZnS quantum dot are laminated according to an embodiment of the present invention and a comparative example, and FIG. 10 (d) 3 is a graph showing experimental results of measurement of photoluminescence intensity of a three-dimensional laminated structure.

10 (d), when the h-BN functional layer is formed only in one direction of the quantum dots and when the h-BN and the graphene functional layer are formed in both directions, the light emission intensity is 15% , And 88%, respectively. The photoluminescence intensity measurement experiment shows that the multilayer structure can transfer energy more effectively than when a single functional layer is formed by stacking multiple functional layers above and below the quantum dot at which energy is absorbed.

Therefore, the three-dimensional laminated structure according to an embodiment of the present invention can efficiently stack the quantum dots and the functional layer (two-dimensional transition metal dicalcogenide, graphene, h-BN), and the energy absorbed by the quantum dots through the functional layer It is possible to improve the transmission rate of the signal.

11 is a schematic diagram showing an application example of an optoelectronic device including a three-dimensional laminate structure 10 according to an embodiment of the present invention.

11, a quantum dot layer 310 including a first block layer 100 and a second block layer 200 including a functional layer having a two-dimensional structure and a quantum dot 310 capable of absorbing energy is formed on the first block layer 100, It can be seen that the stacked three-dimensional laminated structure 10 is utilized as an LED, a solar cell, a photodetector, and a memory. Energy can be effectively transferred to the functional layers formed on the upper and lower portions of the quantum dot 310 and the optoelectronic device having excellent electrical characteristics can be manufactured using the three-dimensional laminated structure 10. [

Accordingly, the present invention can efficiently stack the functional layers of two-dimensional structure and the quantum dots of the zero-dimensional structure, and the three-dimensional laminated structure manufactured through the method can improve the electrical characteristics of the three-dimensional laminated structure including the quantum dots having high light efficiency .

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is clearly understood that the same is by way of illustration and example only and is not to be taken in conjunction with the present invention. Variations and changes are possible. Such variations and modifications are to be considered as falling within the scope of the invention and the appended claims.

10: laminated structure
50: substrate
100: first block layer
110: first functional layer
120: second functional layer
200: second block layer
230: third functional layer
240: fourth functional layer
300: Quantum dot layer
310: QD
500: metal plate layer
510: carrier polymer layer

Claims (12)

(a) forming a first block layer including at least one functional layer;
(b) transferring the first block layer onto a substrate;
(c) forming a quantum dot layer including quantum dots of a core-shell structure on at least a part of the first block layer;
(d) forming a second blocking layer including at least one functional layer; And
(e) stacking the second block layer on the quantum dot layer
And a step of forming the three-dimensional laminated structure. The method according to claim 1,
Further comprising laminating the quantum dot layer and the first block layer or the second block layer on the second block layer. The method according to claim 1,
The step (a)
(a1) forming a first functional layer on a metal plate layer;
(a2) forming a carrier polymer layer on the first functional layer;
(a3) removing the metal plate layer and
(a4) removing the carrier polymer layer
And a step of forming the three-dimensional laminated structure. The method of claim 3,
After the step (a3)
(a5) forming a second functional layer on the metal plate layer;
(a6) transferring the first functional layer and the carrier polymer layer onto the second functional layer and
(a7) removing the metal plate layer
Further comprising a step of forming the three-dimensional laminate structure. The method according to claim 1,
The step (d)
(d1) forming the third functional layer on the metal plate layer;
(d2) forming a carrier polymer layer on the third functional layer;
(d3) removing the metal plate layer and
(d4) removing the carrier polymer layer
And a step of forming the three-dimensional laminated structure. 6. The method of claim 5,
After the step (d3)
(d5) forming a fourth functional layer on the metal plate layer;
(d6) transferring the third functional layer and the carrier polymer layer onto the fourth functional layer, and
(d7) removing the metal plate layer
Further comprising a step of forming the three-dimensional laminate structure. The method according to claim 1,
Wherein the functional layer is formed by a chemical vapor deposition method using a functional material precursor. The method according to claim 1,
Wherein the functional layer is any one selected from the group consisting of graphene, h-BN, WSe _2, and MoS ₂ . The method according to claim 1,
Wherein the quantum dot layer is formed by spin coating a quantum dot of a core-shell structure. The method according to claim 1,
The quantum dots of the core-
Wherein the core is any one selected from the group consisting of CdSe, CdTe, CdS, InP, ZnCdSe, PbS, PbSe, CGS, CIGS, and CIS,
Wherein the shell is any one selected from the group consisting of ZnS, CdS, and ZnSe. The method according to claim 1,
Wherein the substrate comprises silicon and silicon oxide. ≪ RTI ID = 0.0 > 11. < / RTI > A three-dimensional laminate structure produced by the method of any one of claims 1 to 11.

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