KR102521232B1 - Multi Wavelength Optical Apparatus Using Two-Dimensional Material and Manufacturing Method thereof - Google Patents

Abstract

Disclosed are a multi-wavelength optical element using two-dimensional materials and a manufacturing method thereof. According to one aspect of the present embodiment, the multi-wavelength optical element manufacturing method comprises: a first forming process in which a mask layer is formed on a substrate; a second forming process in which a window layer of a preset pattern is formed in the mask layer; a regrown process of re-growing components of the substrate on the mask layer, on which the window layer is formed, in a preset environment; a deposition process of depositing a two-dimensional material on a regrown substrate; a growth process of growing an epi layer of an optical element on the deposited two-dimensional material; and a separation process of separating the deposited two-dimensional material.

Description

Multi-Wavelength Optical Apparatus Using Two-Dimensional Material and Manufacturing Method thereof

The present invention relates to a multi-wavelength optical device manufactured using a two-dimensional material and a manufacturing method thereof.

The contents described in this part merely provide background information on the present embodiment and do not constitute prior art.

In general, a white light emitting device (White LED) is widely used as a backlight for lighting devices or display devices.

Conventionally, in manufacturing such a white light emitting device, it is largely divided into a method using a phosphor and a method not using a phosphor.

First, as a method of using a phosphor, a method of applying a yellow phosphor to a blue light emitting device is the simplest and widely used. However, the method using the phosphor has a problem in that the color rendering index, which is an index indicating how close to sunlight the color is expressed based on sunlight as 100, is too low and is not suitable for use for lighting.

The method without using phosphors is a method of modularizing and manufacturing three types of light sources, red, green, and blue, and the color rendering index is excellent compared to the method using the above phosphors. However, the light emitting device manufactured by the corresponding method has low price competitiveness, and if even one of the three types of red, green, and blue light sources loses output, the efficiency of the entire light emitting device decreases, eventually adversely affecting the lifespan. In addition, in order to obtain desired white light, it is necessary to finely adjust the current of each light source, along with the problem of requiring a complicated circuit configuration for this purpose, and space constraints in that a plurality of light sources are used to increase the resolution of the display. has been a hindrance

Due to this problem, a method of manufacturing a light emitting device by growing a light emitting device on a substrate having a shape of an inclined plane has emerged recently. When a light emitting device is grown on an inclined plane substrate, the wavelength band of light irradiated at each position is different. Accordingly, by adjusting the size of the light emitting device, it is possible to adjust the wavelength band (including the white wavelength band) to be output by the light emitting device to be manufactured.

Although this method has significantly superior effects compared to conventional methods in manufacturing and operating the light emitting device, there is a very difficult problem in manufacturing the light emitting device in the form of a chip or module due to the morphological characteristics of the substrate. Since there are structurally significant difficulties in the process of electrically connecting electrodes to the light emitting device, there was difficulty in manufacturing the manufactured light emitting device in the form of a chip or module.

An object of one embodiment of the present invention is to provide a semi-polar/non-polar substrate easily separated into substrates using a two-dimensional material and a method for manufacturing the same.

In addition, an object of one embodiment of the present invention is to provide a multi-wavelength optical device that can be easily grown and manufactured on a semi-polarized/non-polarized substrate and a method for manufacturing the same.

According to one aspect of the present invention, a first formation process of forming a mask layer on a substrate, a second formation process of forming a window layer of a predetermined pattern in the mask layer, and a predetermined pattern on the mask layer on which the window layer is formed. A regrowth process of re-growing the components of the substrate in the environment, a deposition process of depositing a 2D material on the re-grown substrate, a growth process of growing an epitaxial layer of an optical device on the deposited 2D material, and separating the deposited 2D material It provides a multi-wavelength optical device manufacturing method characterized in that it comprises a separation process to.

According to one aspect of the present invention, the preset pattern is characterized in that it is formed by etching in a preset direction with a preset interval to the mask layer.

According to one aspect of the present invention, the regrowth substrates in the regrowth process are characterized in that they regrow into different shapes according to a preset environment.

According to one aspect of the present invention, the preset environment is characterized in that the pressure and temperature are different.

According to one aspect of the present invention, the substrate regrown in the regrowth process has a triangular shape as the pressure relatively increases and the temperature decreases, and a trapezoid in which the upper side becomes longer and the hypotenuse becomes shorter as the pressure relatively decreases and the temperature rises. It is characterized by having a shape.

According to one aspect of the present invention, the two-dimensional material is deposited in the form of a thin film having the characteristics of the substrate on which it is deposited, and is separated by receiving an external force, or has a characteristic of changing its shape in the direction in which an external force is applied to be

According to one aspect of the present invention, a multi-wavelength optical device characterized in that it is manufactured according to the above method is provided.

According to one aspect of the present invention, a first formation process of forming a mask layer on a substrate, a second formation process of forming a window layer of a predetermined pattern in the mask layer, and a predetermined pattern on the mask layer on which the window layer is formed. A regrowth process of re-growing the components of the substrate in the environment, a deposition process of depositing a 2D material on the re-grown substrate, a growth process of growing an epitaxial layer of an optical device on the deposited 2D material, and a separation of the deposited 2D material A separation process and a transfer process of transferring the separated two-dimensional material and the epitaxial layer grown on the two-dimensional material to another substrate, wherein the two-dimensional material is deposited in the form of a thin film having the characteristics of the substrate on which it is deposited It provides a multi-wavelength optical device manufacturing method characterized in that it is separated by receiving an external force or has a characteristic of changing its shape in the direction in which an external force is applied.

According to one aspect of the present invention, the epitaxial layer is characterized in that it comprises an n-type semiconductor layer, an active layer and a p-type semiconductor layer.

According to one aspect of the present invention, the regrowth substrate in the regrowth process is characterized in that it regrows in a triangular or trapezoidal shape according to a preset environment.

According to one aspect of the present invention, the active layer is characterized by irradiating light of different wavelength bands according to the grown position.

According to one aspect of the present invention, the two-dimensional material is characterized in that it is straightened by receiving pressure from vertically upward and downward.

According to one aspect of the present invention, the two-dimensional material is characterized in that it is straightened by receiving tensile forces from the left and right sides.

According to one aspect of the present invention, a multi-wavelength optical device characterized in that it is manufactured according to the above method is provided.

As described above, according to one aspect of the present invention, there is an advantage in that a GaN substrate can be easily manufactured using a two-dimensional material and a multi-wavelength optical device can be easily grown and manufactured on the substrate.

1 is a view showing a crystal plane of GaN related to a GaN substrate according to an embodiment of the present invention.
2 is a diagram illustrating a process of remote epitaxy using a two-dimensional material according to an embodiment of the present invention.
3 is a flowchart illustrating a method of manufacturing a multi-wavelength optical device according to an embodiment of the present invention.
4 to 8, 10 and 11 are diagrams illustrating a process of manufacturing a multi-wavelength optical device according to an embodiment of the present invention.
9 is a graph showing optical elements grown on an inclined surface and wavelengths of light emitted from each grown position.

Since the present invention can make various changes and have various embodiments, specific embodiments will be illustrated in the drawings and described in detail. However, this is not intended to limit the present invention to specific embodiments, and should be understood to include all modifications, equivalents, or substitutes included in the spirit and technical scope of the present invention. Like reference numerals have been used for like elements throughout the description of each figure.

Terms such as first, second, A, and B may be used to describe various components, but the components should not be limited by the terms. These terms are only used for the purpose of distinguishing one component from another. For example, a first element may be termed a second element, and similarly, a second element may be termed a first element, without departing from the scope of the present invention. The term and/or includes a combination of a plurality of related recited items or any one of a plurality of related recited items.

It is understood that when an element is referred to as being "connected" or "connected" to another element, it may be directly connected or connected to the other element, but other elements may exist in the middle. It should be. On the other hand, when an element is referred to as “directly connected” or “directly connected” to another element, it should be understood that no intervening element exists.

Terms used in this application are only used to describe specific embodiments, and are not intended to limit the present invention. Singular expressions include plural expressions unless the context clearly dictates otherwise. It should be understood that terms such as "include" or "having" in this application do not exclude in advance the possibility of existence or addition of features, numbers, steps, operations, components, parts, or combinations thereof described in the specification. .

Unless defined otherwise, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which the present invention belongs.

Terms such as those defined in commonly used dictionaries should be interpreted as having a meaning consistent with the meaning in the context of the related art, and unless explicitly defined in the present application, they should not be interpreted in an ideal or excessively formal meaning. don't

In addition, each configuration, process, process or method included in each embodiment of the present invention may be shared within a range that does not contradict each other technically.

1 is a view showing a crystal plane of GaN related to a GaN substrate according to an embodiment of the present invention.

Referring to FIG. 1, the GaN crystal 100 is non-polar with a crystal direction perpendicular to the C-axis (A-plane 1120 or M-plane 1100), or C-plane. It may exhibit semi-polarity with a crystal orientation between 0 and 90 degrees with respect to the (0001) plane or the C-plane (0001).

According to an embodiment of the present invention, the semi-polarity of the GaN crystal 100 exists between the crystal planes of the non-polar A-plane 1120 and M-plane 1100 and the polarized C-plane. At this time, the semi-polar plane extends across the hexagonal unit cell in the polygonal direction, and may form an angle other than 90 degrees with the C-axis.

2 is a diagram illustrating a process of remote epitaxy using a two-dimensional material according to an embodiment of the present invention.

Referring to FIG. 2 , a two-dimensional material 220 having a thickness equal to or less than a predetermined reference value in units of nanometers (nm) or atomic layers is deposited on a GaN substrate 210 . Here, the two-dimensional material 220 is a very thin thin film having an atomic layer thickness, and has high strength and excellent electrical properties comparable to steel while having transparency and flexibility. In addition, it is deposited in the form of a thin film having the properties of the substrate on which it is deposited. As shown in FIG. 2, when the 2D material 220 is deposited on the GaN substrate 210, the 2D material 220 has the crystal information of the GaN substrate 210 (or the surface potential in which the lattice constant is reflected). distribution) has the same characteristics as On the other hand, the two-dimensional material has a characteristic that it is easily separated (separated) by receiving an external force from the substrate on which it is deposited, or its shape is easily changed in the direction in which the external force is applied. Examples of the two-dimensional material 220 having the above characteristics include graphene, fluorographene, graphene oxide, boron nitride (BN), and hexagonal boron nitride (h-BN). : Hexagonal Boron Nitride), transition metal dichalcogenide (TMDC) or transition metal dichalcogenide (TMTC: transition metal dichalcogenide).

3 is a flowchart illustrating a method of manufacturing a multi-wavelength optical device according to an embodiment of the present invention, and FIGS. 4 to 8, 10 and 11 are processes of manufacturing a multi-wavelength optical device according to an embodiment of the present invention. is a drawing showing Manufacture of the multi-wavelength optical device shown in FIG. 3 may be implemented by a multi-wavelength optical device manufacturing apparatus.

A mask layer 410 is formed on the substrate 210 (S310). As shown in FIG. 4 , a mask layer 410 is formed on the GaN substrate 210 . The mask layer 410 is implemented with a dielectric material, and may be implemented with SiO ₂ or SiN _x (x is a natural number, for example, Si ₃ N ₄ ).

A window layer 510 having a predetermined pattern is formed in the mask layer 410 (S320). As shown in FIG. 5 , etching proceeds in a preset direction with a preset spacing to the mask layer 410 . Accordingly, the mask layer 410 remains at predetermined intervals, and the window layer 510 exposing the substrate 210 is formed between each mask layer 410 .

The substrate is re-grown on the mask layer 410 on which the window layer 510 is formed (S330). As shown in FIG. 6, after the window layer 510 is formed at predetermined intervals within the mask layer 410, the GaN substrate is re-grown on the mask layer 410 in a predetermined environment. That is, the same components of the GaN substrate 210 are re-grown onto the mask layer 410 . At this time, when the same component as the GaN substrate is re-grown, the growth form becomes different as the preset environment, more specifically, the pressure and temperature change. As the pressure is relatively increased and the temperature is lowered, it grows in a triangular shape (210b), and as the pressure becomes weaker and the temperature is increased therefrom, it grows in the shape of an isosceles trapezoid (210c, 210d). In particular, the lower the pressure and the higher the temperature, the longer the length of the upper beam and the shorter the length of the hypotenuse.

A two-dimensional material 220 is deposited on the regrown substrate (S340). As shown in FIG. 7 , a two-dimensional material 220 is deposited on a substrate 210b regrown in a preset environment. Deposition of the 2D material 220 may be performed by an evaporator.

Each epitaxial layer 810 to 830 of the optical device grows on the deposited two-dimensional material 220 (S350), as shown in FIG. 8, (substrate 210b re-grown into an appropriate shape according to a preset environment Each epitaxial layer of an optical device, more specifically, an n-type semiconductor layer 810, an active layer 820, and a p-type semiconductor layer 830 are grown on the deposited two-dimensional material 220. Here, the n-type semiconductor layer 810 may be implemented with n-AlInGaN to constitute an n-type layer, and the p-type semiconductor layer 830 may be implemented with p-AlInGaN to constitute a p-type layer.

The growth of the epitaxial layer may be performed by a metal organic chemical vapor deposition (MOCVD) process, a hydride vapor phase epitaxy (HVPE) process, or a molecular beam epitaxy (MBE) process.

At this time, the re-grown substrate 210b always has an inclined surface no matter what environment it grows. Accordingly, when the epitaxial layers 810 to 830 of the optical device grow on the inclined surface of the substrate 210b, the effect shown in FIG. 9 may occur.

9 is a graph showing optical elements grown on an inclined surface and wavelengths of light emitted from each grown position.

FIG. 9(b) shows the intensity for each wavelength band of light irradiated from the active layer 820 at each position 1 to 5 shown in FIG. 9(a). Referring to FIG. 9( b ) , it can be confirmed that the wavelength band of light irradiated from the active layer 820 is different for each position when an optical element is grown on an inclined surface.

Referring back to FIG. 3, as described above, since the two-dimensional material 220 has the characteristics of the substrate on which it is deposited, it is difficult to form the epitaxial layers 810 to 830 of each optical device onto the two-dimensional material 220. can grow without The epitaxial layers 810 to 830, particularly the active layer 820, grown on the deposited 2D material 220 may emit light of different wavelength bands.

The two-dimensional material 220 deposited on the re-grown substrate 210b is separated (S360). As shown in FIG. 10, after each epitaxial layer 810 to 830 of an optical device is grown on the dimensional material, the 2D material 220 is separated from the regrown substrate 210b. Even if only an external force of a preset strength acts, the 2D material 220 can be separated from the regrown substrate 210b without difficulty.

The separated 2D material 220 and the epitaxial layers 810 to 830 grown on the 2D material 220 are transferred to another substrate 1110 (S370). As shown in FIG. 11, when the separation of the 2D material 220 is completed, the separated 2D material 220 and the epitaxial layers 810 to 830 grown on the 2D material 220 are transferred to another substrate 1110. ) to be transcribed. As described above, since the two-dimensional material 220 has flexibility, it can be straightened when pressure is applied from vertically upward or downward, or when tensile forces are applied from the left or right sides of the two-dimensional material 220 . As such, pressure or tensile force is applied to the 2D material 220 and the epitaxial layers 810 to 830 grown on the 2D material 220 to straighten them, and then transferred to another substrate 1110 .

In this way, as the epitaxial layers 810 to 830 are transferred onto the other substrate 1110, optical devices may be entirely manufactured through the remaining optical device manufacturing processes (mesa etching, metal layer arrangement, passivation process, etc.). At this time, since the epitaxial layers 810 to 830 are made of one optical device, the wavelength band of light to be output by the optical device may vary depending on how much area is included. As described above, since the active layer 820 irradiates light of a different wavelength band at each location, the wavelength of light to be output is determined depending on how much area of the active layer 820 is included in the optical device. When the entire area of the active layer 820 that outputs the visible light wavelength band is included in one optical device, the optical device can be implemented as a single device that outputs white light without separately including a light source that outputs red, blue, and green light. there is.

The above description is merely an example of the technical idea of the present embodiment, and various modifications and variations can be made to those skilled in the art without departing from the essential characteristics of the present embodiment. Therefore, the present embodiments are not intended to limit the technical idea of the present embodiment, but to explain, and the scope of the technical idea of the present embodiment is not limited by these embodiments. The scope of protection of this embodiment should be construed according to the claims below, and all technical ideas within the scope equivalent thereto should be construed as being included in the scope of rights of this embodiment.

100: GaN crystal
210: GaN substrate
220: two-dimensional material
410: mask layer
510: window layer
810 to 830: epi layer
1110: substrate

Claims (14)

A first forming process of forming a mask layer on a substrate;
a second forming process in which a window layer having a predetermined pattern is formed in the mask layer;
a re-growth process of re-growing components of the substrate onto the mask layer on which the window layer is formed in a preset environment;
A deposition process of depositing a two-dimensional material on the regrown substrate;
A growth process of growing an epitaxial layer of an optical device on the deposited two-dimensional material; and
Including a separation process for separating the deposited two-dimensional material,
According to the regrowth process, the same component as the substrate grows in a triangular shape or an isosceles trapezoidal shape,
The two-dimensional material is deposited in the form of a thin film having the characteristics of the substrate on which it is deposited, has transparency and flexibility, and has the characteristic of being separated by external force or changing its shape in the direction in which the external force is applied. Characterized in that Multi-wavelength optical device manufacturing method. According to claim 1,
The preset pattern is,
The method of manufacturing a multi-wavelength optical device, characterized in that the mask layer is formed by etching in a predetermined direction at a predetermined interval. According to claim 1,
The substrate re-grown in the re-growth process,
A method of manufacturing a multi-wavelength optical device, characterized in that it re-grows into different shapes according to a preset environment. According to claim 3,
The preset environment is
A method for manufacturing a multi-wavelength optical device characterized in that pressure and temperature are varied. According to claim 4,
The substrate re-grown in the re-growth process,
A method for manufacturing a multi-wavelength optical device, characterized in that it has a triangular shape as the pressure relatively increases and the temperature decreases, and a trapezoid shape in which the upper side becomes longer and the hypotenuse becomes shorter as the pressure relatively decreases and the temperature rises. delete A multi-wavelength optical device characterized in that it is manufactured according to the method of any one of claims 1 to 5. A first forming process of forming a mask layer on a substrate;
a second forming process in which a window layer having a predetermined pattern is formed in the mask layer;
a re-growth process of re-growing components of the substrate onto the mask layer on which the window layer is formed in a preset environment;
A deposition process of depositing a two-dimensional material on the regrown substrate;
A growth process of growing an epitaxial layer of an optical device on the deposited two-dimensional material;
Separation process of separating the deposited two-dimensional material; and
It includes a transfer process of transferring the separated two-dimensional material and the epitaxial layer grown on the two-dimensional material to another substrate,
According to the regrowth process, the same component as the substrate grows in a triangular shape or an isosceles trapezoidal shape,
The two-dimensional material is deposited in the form of a thin film having the characteristics of the substrate on which it is deposited, has transparency and flexibility, and has the characteristic of being separated by external force or changing its shape in the direction in which the external force is applied. Characterized in that Multi-wavelength optical device manufacturing method. According to claim 8,
The epi layer,
A method for manufacturing a multi-wavelength optical device comprising an n-type semiconductor layer, an active layer, and a p-type semiconductor layer. According to claim 9,
The substrate re-grown in the re-growth process,
A method of manufacturing a multi-wavelength optical device, characterized in that it re-grows in a triangular or trapezoidal shape according to a predetermined environment. According to claim 10,
The active layer,
A method for manufacturing a multi-wavelength optical device, characterized in that irradiating light of different wavelength bands according to a grown position. According to claim 8,
The two-dimensional material,
A method of manufacturing a multi-wavelength optical device characterized in that it is straightened by receiving pressure from vertically upward and downwardly. According to claim 8,
The two-dimensional material,
A method of manufacturing a multi-wavelength optical device characterized in that it is straightened by receiving tensile force from the left and right sides. A multi-wavelength optical device produced by the method of any one of claims 8 to 13.

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