TW201238887A - A method for making epitaxial structure - Google Patents

Abstract

The present invention relates to a method for making epitaxial structure. The method includes following steps of: providing a substrate having an epitaxial growth surface; placing a first carbon nanotube layer on the epitaxial growth surface; epitaxially growing a first epitaxial layer on the epitaxial growth surface to cover the first carbon nanotube layer; placing a second carbon nanotube layer on the first epitaxial layer; and epitaxially growing a second epitaxial layer on the first epitaxial layer to cover the second carbon nanotube layer. The method is simple and low cost.

Description

201238887 VI. Description of the Invention: [Technical Field of the Invention] [0001] The present invention relates to a method for preparing an epitaxial body. [Prior Art] [0002] Epitaxial structures, particularly heteroepitaxial structures, are one of the main materials for fabricating semiconductor devices. For example, in recent years, gallium nitride epitaxial wafers for preparing light-emitting diodes (LEDs) have become a research hotspot. [0003] The gallium nitride epitaxial wafer refers to a gallium nitride material divided into a regular arrangement and grown on a sapphire substrate under certain conditions. However, the preparation of high quality GaN epitaxial wafers has been a difficult point of research. Due to the difference in lattice constant and thermal expansion coefficient of the gallium and sapphire substrates, there are many dislocation defects (disl() catiQn defect) in the gallium nitride epitaxial layer. Moreover, there is a relatively large stress between the gallium nitride epitaxial layer and the sapphire substrate, and the greater the stress, the GaN epitaxial layer is broken. This heteroepitaxial structure generally has a lattice loss phenomenon, and (4) defects such as misalignment 〇 先前 The prior art provides a method for improving the above-mentioned deficiencies, which uses a non-flat blue to epitaxially grow gallium nitride. However, the prior art generally uses a microelectronic method such as photolithography to form a groove on the surface of the sapphire substrate to form a non-planar epitaxial growth surface. This method not only has a complicated manufacturing process, but also has a high cost, and it also pollutes the epitaxial growth surface of the sapphire substrate, thereby affecting the quality of the epitaxial structure. SUMMARY OF THE INVENTION [0005] In summary, the description of ^ A,» consumption is a simple process, the cost is low, and the method of preparing the epitaxial structure Zhao which does not cause dyeing of the substrate surface is necessary. 100112867 Form No. Α0101 « 0 1002021430-0 Page 3 / Total 48 Pages 201238887 [0006] A method of preparing an epitaxial structure, comprising the steps of: providing a substrate, the germanium substrate having an epitaxial growth surface; a first carbon nanotube layer is disposed on the epitaxial growth surface; a first epitaxial layer is grown on the epitaxial growth surface of the substrate and covers the first carbon nanotube layer; and a second surface is disposed on the surface of the first epitaxial layer a carbon nanotube layer, wherein a surface of the first epitaxial layer is an epitaxial growth surface of the first epitaxial layer; and a second epitaxial layer is grown on the surface of the first epitaxial layer and covers the second nano-layer Carbon tube layer. [0007] A method for preparing an epitaxial structure, comprising the steps of: providing a substrate having an epitaxial growth surface; providing a photomask layer on an epitaxial growth surface of the substrate; and growing on an epitaxial growth surface of the substrate The ins layer covers the photomask layer; the surface of the first epitaxial layer is sequentially stacked to grow the second to eleven epitaxial layers, and at least one adjacent epitaxial layer is provided with a photomask layer; wherein η is greater than or equal to 3 An integer of at least one of the mask layers in the mask layer is a carbon nanotube layer. Compared with the prior art, the method for obtaining a patterned photomask by providing a carbon nanotube layer on the epitaxial growth surface of the substrate is simple in process and low in cost, and the preparation cost of the epitaxial structure is greatly reduced. At the same time, it reduces the pollution to the environment. The epitaxial structure comprising the carbon nanotube layer allows the epitaxial structure to have a wide range of uses. [Embodiment] [00091] The epitaxial structure, the stopper, and the preparation method thereof according to the embodiments of the present invention will be described in detail below with reference to the accompanying drawings. In order to facilitate understanding of the technical solution of the present invention, the present invention first introduces a method of preparing an epitaxial structure. 100112867 Please refer to FIG. 1, Form No. Α0101. Embodiments of the present invention provide an epitaxial structure j. Preparation of page 4/48 pages 100 1002021430-0 [0010] 201238887 [0011] [0012] [0014] [0014] [0016] 〇100112867 The method specifically includes the following steps: S1〇: providing a substrate 1〇〇, and the substrate 1〇〇 has an epitaxial growth surface 1〇1 supporting the growth of the first epitaxial layer 104; S20: a first carbon nanotube layer 102 is disposed on the epitaxial growth surface 1〇1 of the substrate 10〇; S30: a first epitaxial layer 104 is grown on the epitaxial growth surface 1〇1 of the substrate 1 ;; S40: A surface 1〇6 of the first epitaxial layer 1〇4 is provided with a first carbon nanotube layer 107; S50: a second epitaxial layer 109 is grown on the surface 1〇6 of the first epitaxial layer 1〇4. In step S10, the substrate 1 is provided with an epitaxial growth surface 101 of the epitaxial layer 1〇4. The epitaxial growth surface 101 of the substrate 100 is a molecularly smooth surface, and impurities such as oxygen or carbon are removed. The substrate 100 can be a single layer or a plurality of layers. When the substrate 100 has a single layer structure, the substrate 100 may be a single crystal structure and have a crystal plane as the epitaxial growth surface 101 of the first epitaxial layer 104. The material of the single-layer structure substrate 100 may be GaAs, GaN, Si, SOI (Siiicon inn insultor), AIN, SiC, MgO, ZnO, LiGaO, LiAlO. Or Al9〇, etc. When the substrate 100 is a plurality of layers, it is necessary to include at least one layer of the single crystal structure, and the single crystal structure has a crystal plane as the epitaxial growth surface 101 of the first epitaxial layer 104. The material of the substrate 1 可 may be selected according to the first epitaxial layer 1G4 to be grown, and preferably, the substrate 100 and the epitaxial layer 1G4 have similar lattice constants and thermal expansion coefficients. The thickness 大小, thickness, size and shape of the substrate are not limited, and can be selected according to the actual number of the form page 5 / 48 pages should be selected 201238887. The substrate 100 is not limited to the materials listed above, as long as the substrate 100 having the epitaxial growth surface 1〇1 supporting the growth of the first epitaxial layer 104 is within the scope of the present invention. [0017] In step S20, the first carbon nanotube layer 102 is a continuous overall structure including a plurality of carbon nanotubes. The plurality of carbon nanotubes in the first carbon nanotube layer 1〇2 extend in a direction substantially parallel to the surface of the first carbon nanotube layer i 〇 2 . When the first carbon nanotube layer 1〇2 is disposed on the epitaxial growth surface 101 of the substrate 1 , the extending direction of the plurality of carbon nanotubes in the first carbon nanotube layer 1〇2 is basically An epitaxial growth surface 1〇1 parallel to the substrate 1〇〇. The thickness of the first carbon nanotube layer 1〇2 is 1 nm to 1 μm, or 1 nm to 1 μm, or 1 nm to 2 μN, preferably 1 N Meters ~ 100 nm. The first carbon nanotube layer 102 can be a patterned carbon nanotube layer. The ''patterning' means that the first carbon nanotube layer 102 has a plurality of first openings 105, and the plurality of first openings 105 penetrate through the thickness direction of the first carbon nanotube layer 102. The first carbon nanotube layer is 1〇2. When the first carbon nanotube layer 102 covers the epitaxial growth surface 101 of the substrate 1 , so that the epitaxial growth surface 1 〇 1 of the substrate 1 对 corresponds to the first opening 1 〇 5 Partial exposure facilitates growth of the first epitaxial layer 丨〇4. The first opening 105 can be a micro hole or a gap. The size of the first opening 1〇5 is 10 nm to 500 μm, and the size refers to the diameter of the micropores or the pitch of the gap in the width direction. The first opening ^ 〇 5 has a size of 10 nm to 300 μm, or 10 nm to 12 μm or 1 〇 nanometer to 80 μm, or 1 〇 nanometer to 1 μm. The smaller the size of the first opening 1〇5, the smaller the generation of misalignment defects during the growth of the epitaxial layer, to obtain the high-quality first epitaxial layer 1〇4. Preferably said first opening 100112867 Form No. A0101 Page 6 / Total 48 pages 1002021430-0 201238887 [0018] [0020] The size of 100112867 105 is from 10 nm to 1 μm. Further, the duty ratio of the first carbon nanotube layer 102 is 1:100~100:1, or 1:1〇~1〇:1, or 1:2~2:1, or 1:4 ~4:1. Preferably, the duty cycle is four. The term "duty ratio" means that the first carbon nanotube layer 1〇2 is disposed on the epitaxial growth surface 101 of the substrate 100, and the portion of the epitaxial growth surface 1〇1 occupied by the first carbon nanotube layer 102 is The area ratio of the portion exposed through the first opening 1〇5. Further, the "graphical" means that the arrangement of the plurality of carbon nanotubes in the first carbon nanotube layer 1〇2 is ordered and regular. For example, the first nanometer The axial direction of the plurality of carbon nanotubes in the carbon tube layer 102 is substantially parallel to the epitaxial growth surface of the substrate 1 且 and extends substantially in the same direction. Alternatively, the first carbon nanotube layer 102 has a plurality of The axial direction of the carbon nanotube may extend substantially in more than two directions. Or, the axial direction of the plurality of carbon nanotubes in the first carbon nanotube layer 102 extends along a crystal orientation of the substrate 100 or Extending at an angle to a crystal orientation of the substrate 100. Adjacent carbon nanotubes extending in the same direction in the first carbon nanotube layer 102 are connected end to end by van der Waals f〇rce. On the premise that the first carbon nanotube layer 102 has the first opening 1〇5 as described above, the plurality of carbon nanotubes in the first carbon nanotube layer 102 may also be disorderly arranged, Preferably, the first carbon nanotube layer 102 is disposed on the entire epitaxial growth surface 1 of the substrate 1 1. The carbon nanotubes in the first carbon nanotube layer 1〇2 may be one or a plurality of single-walled carbon nanotubes, double-walled carbon nanotubes or multi-walled carbon nanotubes, The length and diameter can be selected as needed. Form No. 101 0101 Page 7 / Total 48 Page 1002021430-0 201238887 [0022] [0023] The first carbon nanotube layer 102 is used to grow the first epitaxial layer 1 The photomask of 4 means that the first carbon nanotube layer 102 is used to block a portion of the epitaxial growth surface 101 of the substrate 100, and exposes a portion of the epitaxial growth surface 101' such that the first epitaxial layer 1 〇4 is only grown from the exposed portion of the epitaxial growth surface 1〇1. Since the first carbon nanotube layer 1〇2 has a plurality of first openings 1 0 5 , the first nano tube breaking layer 1 〇 2 Forming a patterned mask. After the first carbon nanotube layer 102 is disposed on the epitaxial growth surface 1 〇1 of the substrate 1 , the plurality of carbon nanotubes extend in a direction parallel to the epitaxial growth surface i 〇丨Forming a plurality of first openings 1〇5 due to the first carbon nanotube layer 1〇2 on the epitaxial growth surface 101 of the substrate 10〇, thereby causing the The epitaxial growth surface 1 〇 1 of the bottom 100 has a patterned mask. It can be understood that the method for epitaxial growth by providing a carbon nanotube layer 1 〇 2 mask is simple, compared with microelectronic methods such as photolithography. The cost is low, it is not easy to introduce pollution on the epitaxial growth surface 1 of the substrate 100, and the environmental protection can greatly reduce the preparation cost of the epitaxial structure 1 可以. It can be understood that the substrate 1 and the first carbon nanotube The layers 102 collectively constitute a substrate for growing the first epitaxial layer 〇4. The substrate can be used to grow a first epitaxial layer 不同4 of a different material, such as a semiconductor epitaxial layer, a metal epitaxial layer or an alloy epitaxial layer. The substrate can also be used to grow a homoepitaxial layer. The first carbon nanotube layer 〇2 can be directly formed on the epitaxial growth surface 10 of the substrate 100 after being formed. The first carbon nanotube layer 1〇2 is a macroscopic structure, and the first carbon nanotube layer 1〇2 is a self-supporting structure, and the self-supporting refers to the first carbon nanotube layer. 1〇2 does not require a large area of support, but as long as the support is provided on both sides, it can be suspended and maintained in its own state, that is, the first carbon nanotube layer i02 is placed (100112867 Form No. A0) 01 No. 8 Page / Total 48 pages 1002021430-0 201238887 or = 疋 ) 间隔 间隔 间隔 间隔 间隔 间隔 间隔 间隔 间隔 间隔 间隔 间隔 间隔 间隔 间隔 间隔 第一 第一 第一 第一 第一 第一 第一 第一 第一 第一 第一 第一 第一 第一 第一 第一 第一 第一 第一 第一 第一 第一 第一 第一 第一 第一 第一 第一 第一 第一The carbon tube layer (10) is a self-supporting structure, and the first layer 1〇2 does not have to pass through the epitaxial growth surface m of the base layer ι〇〇 by a leaking chemical method. Preferably, the first carbon nanotube layer, ... L is composed of a plurality of carbon nanotubes composed of a carbon nanotube. The so-called "pure naphthalene does not contain any functional groups such as carboxyl groups" means that the carbon nanotube layer is modified without any chemical modification or acidification treatment throughout the preparation process. The first-nano carbon nanotubes (4) 2 may also be _ a composite structure of a plurality of n-ray tubes and an additive material, and the additive materials include graphite or graphite, carbonized carbide, nitriding, gasification, sulphur dioxide, amorphous carbon, and the like. The additive material may also include one or a plurality of metal carbide metal oxides, metal nitrides, etc. The additive material is coated on at least the carbon nanotubes of the first carbon nanotube layer 1〇2. A portion of the surface is disposed in the first opening 10 5 of the first carbon nanotube layer 102. Preferably, the additive material is coated on the surface of the carbon nanotube. Since the additive material is coated on the nanometer. The surface of the carbon tube makes the diameter of the carbon nanotubes larger, thereby reducing the first opening 105 between the carbon nanotubes. The additive material can be deposited by chemical vapor deposition (CVD), physical vapor deposition ( PVD), magnetron sputtering, etc. Surface of the carbon nanotubes. [0025] After the first carbon nanotube layer 1〇2 is laid on the epitaxial growth surface 101 of the substrate 1 , an organic solvent treatment step may be further included to enable the first step. The carbon nanotube layer 102 is more closely bonded to the epitaxial growth surface 1〇1. The organic solvent may be one of ethanol, decyl alcohol, acetone, dioxane and chloroform or 100112867 Form No. A0101 Page 9 of 48 1002021430-0 201238887 Several kinds of mixing. The organic solvent in this embodiment uses ethanol. The step of treating with an organic solvent can drip the organic solvent on the surface of the first carbon nanotube layer 102 through a test tube to infiltrate the entire first nai. The carbon nanotube layer 102 or the substrate 100 and the entire first carbon nanotube layer 102 are immersed in a container containing an organic solvent to infiltrate. [0026] The first carbon nanotube layer 102 can also pass through a chemical vapor phase. A method such as deposition (CVD) is directly grown on the epitaxial growth surface 101 of the substrate 100 or on the surface of the ruthenium substrate, and then transferred to the epitaxial growth surface 101 of the substrate 100, or the solution containing the carbon nanotubes is directly Epitaxial deposition on the substrate 100 The method of growing surface 101, etc. is formed. [0027] Specifically, the first carbon nanotube layer 102 may include a carbon nanotube film or a nano carbon pipeline. The first carbon nanotube layer 102 may be a single a layer of carbon nanotube film or a plurality of stacked carbon nanotube films. The first carbon nanotube layer 102 may comprise a plurality of parallel carbon nanotubes or a plurality of interdigitated carbon nanotubes. When the first carbon nanotube layer 102 is a plurality of stacked carbon nanotube films, the number of layers of the carbon nanotube film is not too high, preferably 2 to 100. When the first nanocarbon When the tube layer 102 is a plurality of carbon nanotubes arranged in parallel, the distance between the adjacent two nano carbon lines is from 0.1 μm to 200 μm, preferably from 10 μm to 100 μm. The space between the adjacent two nanocarbon lines constitutes a first opening 105 of the first carbon nanotube layer 102. The length of the gap between two adjacent nanocarbon lines may be equal to the length of the nanocarbon line. The carbon nanotube film or the carbon nanotube line may be directly laid on the epitaxial growth surface 101 of the substrate 100 to constitute the first carbon nanotube layer 102. By controlling the number of layers of the carbon nanotube film or the distance between the carbon nanotubes, the first carbon nanotube layer 102 can be controlled to be 100112867. Form No. A0101 Page 10 / Total 48 Page 1002021430-0 201238887 First opening 105 size of. [0028] Ο

The carbon nanotube membrane is a self-supporting structure composed of a number of carbon nanotubes. The plurality of carbon nanotubes extend in a preferred orientation along the same direction. The preferred orientation means that the majority of the carbon nanotubes in the carbon nanotube film extend substantially in the same direction. Moreover, the overall direction of extension of the majority of the carbon nanotubes is substantially parallel to the surface of the carbon nanotube film. Further, the plurality of carbon nanotubes in the carbon nanotube film are connected end to end by van der Waals force. Specifically, each of the plurality of carbon nanotubes extending substantially in the same direction in the carbon nanotube film is connected end to end with a vanadium force in the extending direction. Of course, there are a small number of randomly arranged carbon nanotubes in the carbon nanotube membrane, and these carbon nanotubes do not significantly affect the overall orientation of most of the carbon nanotubes in the carbon nanotube membrane. The self-supporting carbon nanotube film does not require a large-area carrier support, but can maintain a self-membrane state as long as the supporting force is provided on both sides, that is, the carbon nanotube film is placed (or fixed on) When the two supports are placed at a certain distance, the carbon nanotube film located between the two supports can be suspended to maintain the self-membrane state. The self-supporting is mainly achieved by the presence of continuous carbon nanotubes extending through the end of the van der Waals force in the carbon nanotube film. [0029] Specifically, the plurality of carbon nanotubes extending substantially in the same direction in the carbon nanotube film are not absolutely linear and may be appropriately bent; or are not completely aligned in the extending direction, and may be appropriately deviated Extend the direction. Therefore, partial contact between the carbon nanotubes juxtaposed in the plurality of carbon nanotubes extending substantially in the same direction of the carbon nanotube film cannot be excluded. 100112867 Form No. Α 0101 Page 11 of 48 1002021430-0 201238887 [0030] Referring to Figures 2 and 3, in particular, the carbon nanotube membrane comprises a plurality of continuous and oriented elongated carbon nanotube segments 143. The plurality of carbon nanotube segments 143 are connected end to end by van der Waals force. Each of the carbon nanotube segments 143 includes a plurality of carbon nanotubes 145 which are parallel to each other, and the plurality of mutually parallel carbon nanotubes 145 are tightly bonded by van der Waals force. The carbon nanotube segments 143 have any length, thickness, uniformity, and shape. The carbon nanotube film can be obtained by directly drawing a part of a carbon nanotube from an array of carbon nanotubes. The carbon nanotube film has a thickness of from 1 nm to 100 μm, and the width is related to the size of the carbon nanotube array in which the carbon nanotube film is taken out, and the length is not limited. There are micropores or gaps between adjacent carbon nanotubes in the carbon nanotube film to form a first opening 105, and the pore size or gap size of the micropores is less than 10 microns. Preferably, the carbon nanotube film has a thickness of from 100 nm to 10 μm. The carbon nanotubes 145 in the carbon nanotube film extend in a preferred orientation in the same direction. For details of the carbon nanotube film and the preparation method thereof, please refer to the patent No. 13271 77 of the Republic of China patent "Nano Carbon Tube Film Structure" filed on July 12, 2010, filed by the applicant on February 12, 2010. And its preparation method". In order to save space, only the above is cited, but all the technical disclosures of the above application should also be considered as part of the technical disclosure of the present application. [0031] Referring to FIG. 4, when the carbon nanotube layer includes a plurality of laminated carbon nanotube films stacked in a stack, the extending direction of the carbon nanotubes in the adjacent two carbon nanotube films forms a cross. The angle α, and α is greater than or equal to 0 degrees and less than or equal to 90 degrees (0.S α $90.). [0032] In order to reduce the thickness of the carbon nanotube film, the carbon nanotube film may be further subjected to heat treatment. In order to prevent the carbon nanotube film from being destroyed upon heating, the method of heating the carbon nanotube film adopts a local heating method. Specifically, it includes 100112867 Form No. 1010101 Page 12/48 pages 1002021430-0 201238887 ❹ The following steps: locally heating the carbon nanotube film to partially oxidize the carbon nanotube film at a local position; The carbon nanotubes are locally heated to achieve heating of the entire carbon nanotube film from partial to integral. Specifically, the carbon nanotube film can be divided into a plurality of small regions, and the carbon nanotube film is heated region by region in a manner from the local to the whole. The method of locally heating the carbon nanotube film may be plural, such as laser heating, microwave heating, or the like. In this embodiment, the carbon nanotube film is irradiated by a laser scan having a power density of more than 0.1 x 10 4 watts per square meter, and the carbon nanotube film is heated from a partial to a whole. The carbon nanotube film is irradiated by laser, and some of the carbon nanotubes are oxidized in the thickness direction, and at the same time, the larger diameter carbon nanotube bundle in the carbon nanotube film is removed, so that the carbon nanotube film becomes thin. [0033]

It is to be understood that the above method of scanning the carbon nanotube film is not limited as long as the carbon nanotube film can be uniformly irradiated. The laser scanning can be carried out row by row along the arrangement direction of the carbon nanotubes in the parallel carbon nanotube film, or can be carried out column by column along the arrangement direction of the carbon nanotubes perpendicular to the carbon nanotube film. The smaller the speed of the laser-scanned carbon nanotube film with fixed power and fixed wavelength, the more heat absorbed by the carbon nanotube bundle in the carbon nanotube film, the more the corresponding carbon nanotube bundle is destroyed, after laser treatment The thickness of the carbon nanotube film becomes small. However, if the laser scanning speed is too small, the carbon nanotube film will absorb too much heat and be burned. 5秒。 In this embodiment, the laser power density is greater than 0. 053x1 012 watts / square meter, the diameter of the laser spot is in the range of 1 mm to 5 mm, the laser scanning exposure time is less than 1.8 seconds. Preferably, the laser is a carbon dioxide laser having a power of 30 watts, a wavelength of 10.6 microns, a spot diameter of 3 mm, a laser device and a nanometer 100112867 Form No. A0101 Page 13 of 48 Page 1002021430-0 201238887 The relative movement speed of the carbon film is less than ίο mm / sec. [0034] The nanocarbon line may be a non-twisted nanocarbon line or a twisted nanocarbon line. The non-twisted nanocarbon line and the twisted nanocarbon line are both self-supporting structures. Specifically, referring to Figure 5, the non-twisted nanocarbon pipeline includes a plurality of carbon nanotubes extending in a direction parallel to the length of the non-twisted nanocarbon pipeline. Specifically, the non-twisted nanocarbon pipeline includes a plurality of carbon nanotube segments, and the plurality of carbon nanotube segments are connected end to end by a van der Waals force, and each of the carbon nanotube segments includes a plurality of parallel and pass through a van der Waals force. Tightly bonded carbon nanotubes. The carbon nanotube segments have any length, thickness, uniformity, and shape. 5纳米至1 00微米。 The non-twisted nano carbon line length is not limited, the diameter is 0. 5 nm ~ 1 00 microns. The non-twisted nano carbon line is obtained by treating the carbon nanotube membrane with an organic solvent. Specifically, the organic solvent is used to impregnate the entire surface of the carbon nanotube film, and the mutually parallel complex carbon nanotubes in the carbon nanotube film pass through the surface tension generated by the volatilization of the volatile organic solvent. The wattage is tightly combined to shrink the carbon nanotube membrane into a non-twisted nanocarbon pipeline. The organic solvent is a volatile organic solvent such as ethanol, methanol, acetone, dihexane or gas, and ethanol is used in this embodiment. The non-twisted nanocarbon line treated by the organic solvent has a smaller specific surface area and a lower viscosity than the carbon nanotube film which is not treated with the organic solvent. [0035] The twisted nanocarbon line is obtained by twisting both ends of the carbon nanotube film in opposite directions by a mechanical force. Referring to Figure 6, the twisted nanocarbon line includes a plurality of carbon nanotubes extending axially around the twisted nanocarbon line. Specifically, the twisted nanocarbon pipeline includes a plurality of carbon nanotube segments, and the plurality of carbon nanotube segments are connected end to end by van der Waals 100112867 Form No. A0101 Page 14 / 48 pages 1002021430-0 201238887, each The carbon nanotube segments include a plurality of carbon nanotubes that are parallel to each other and closely coupled by van der Waals. The carbon nanotube segments have any length, thickness, uniformity, and shape. 5纳米〜100微米。 The twisted nano carbon line length is not limited, the diameter is 0. 5 nanometers ~ 100 microns. Further, the twisted nanocarbon line can be treated with a volatile organic solvent. Under the action of the surface tension generated by the volatilization of the volatile organic solvent, the adjacent carbon nanotubes in the treated twisted nanocarbon pipeline are tightly bonded by van der Waals to make the specific surface area of the twisted nanocarbon pipeline Decrease, increase in density and strength. [0036] The nano carbon pipeline and the preparation method thereof are referred to the patent of the Republic of China patent No. 1303239, which was filed by the applicant on November 5, 2002, and filed on November 21, 2008. Applicant: Hon Hai Precision Industry Co., Ltd., and the application for the Republic of China patent No. 1 31 2337, filed on December 16, 2005, the applicant: Hon Hai Precision Industry Co., Ltd. [0037] The carbon nanotube film may also be formed by: a, providing a substrate at the bottom of a beaker; b, dispersing the prepared single-walled carbon nanotube carbon tube in a solvent in another beaker, and Ultrasonic shaking for about ten minutes, removing the precipitate and obtaining a solution floating on the surface layer, and then pouring the solution floating on the surface layer into a beaker provided with a substrate; C, heating the beaker to evaporate the solvent, so that the carbon carbon nanotube tube is uniform The deposition on the substrate forms a carbon nanotube film on the surface of the substrate. In addition, the carbon nanotubes in the carbon nanotube film obtained by the method have a non-directional arrangement of carbon nanotubes. It will be understood that the carbon nanotube film may be formed by other methods such as electrophoresis or precipitation. [0038] In step S30, the growth method of the first epitaxial layer 104 may be performed by molecular beam epitaxy (MBE), chemical beam epitaxy (CBE), decompression epitaxy 100112867, form number A0101, page 15 / total 48 pages 1002021430 -0 201238887 ', low temperature epitaxy, selective epitaxy, liquid phase deposition epitaxy (LPE) metal organic vapor phase epitaxy (MOVPE), ultra-vacuum chemical vapor deposition (UHVCVD), hydride vapor phase epitaxy (HVPE) And one or more of metal organic chemical vapor deposition (MOCVD). [0040] The first epitaxial layer 104 refers to a single crystal structure in which the outer growth surface 丨〇1 of the substrate 100 is grown by epitaxial method, and the material thereof is different from the substrate 100, so it can also be called It is a heteroepitaxial layer. The thickness of the growth of the first epitaxial layer 104 can be prepared as needed. 5纳米〜1毫米。 The thickness of the first epitaxial layer 104 may be 0. 5 nanometers ~ 1 mm. For example, the thickness of the first epitaxial layer 1〇4 may be from 1 nanometer to 500 micrometers, or from 200 nanometers to 200 micrometers or from 5 nanometers to 1 micrometer. The first epitaxial layer 1〇4 may be a half-conductor epitaxial layer' and the material of the semiconductor epitaxial layer is GaMnAs, GaAlAs

GalnAs, GaAs, SiGe, InP, Si, AIN, GaN, GalnN A1InN, GaAIN or AlGalnN. The first epitaxial layer may be a five-element epitaxial layer' and the material of the metal epitaxial layer is aluminum, platinum, copper or silver. The first epitaxial layer 104 may be an __alloy epitaxial layer, and the material of the alloy epitaxial layer is MnGa, CoMnGa or Co MnGa. 2 Referring to FIG. 7 'specifically' the growth process of the first epitaxial layer 1 具体 4 specifically includes the following steps: ~ S31 : nucleation along the epitaxial growth plane substantially perpendicular to the substrate 1 并Epitaxially growing a plurality of epitaxial grains 1 〇 42; [0042] S32: the plurality of epitaxial grains 1042 are epitaxially grown along a substantially parallel epitaxial growth surface 101 to form a continuous film 1044; & epitaxial thin 100112867 Form No. A0101 Page 16 / Total 48 Page 1002021430-0 201238887 [0044] [0045] Ο

[0046] S33: the epitaxial film 1〇44 is epitaxially grown along a direction perpendicular to the epitaxial growth surface 1〇1 of the substrate 1形成 to form a first epitaxial layer 1〇4. In step S31, the complex epitaxial grains 1042 are grown on the epitaxial growth surface 101 of the substrate 1 through the portion of the first opening 105 of the first carbon nanotube layer 1〇2, and The growth direction is substantially perpendicular to the epitaxial growth surface 1〇1 of the substrate 1〇0, that is, the plurality of epitaxial grains 1〇42 in this step are longitudinally epitaxially grown. In step S32, 'the first epitaxial grains 1 〇 42 are homogenously epitaxially grown and integrated in a direction substantially parallel to the epitaxial growth surface 101 of the substrate 1 by controlling growth conditions to integrate the first nanometer. The carbon tube layer is covered by 1〇2. That is, in the step, the plurality of epitaxial grains 1 〇 42 are laterally epitaxially grown and directly closed, and finally a plurality of first holes 1 〇 3 are formed around the carbon nanotubes to surround the carbon nanotubes. Preferably, the carbon nanotubes are spaced apart from the first epitaxial layer 104 surrounding the carbon nanotubes. The shape of the holes is related to the arrangement direction of the carbon nanotubes in the first carbon nanotube layer 102. When the first carbon nanotube layer 102 is a single-layer nano tube or a plurality of parallel carbon nanotubes, the plurality of first holes 103 are substantially parallel grooves. When the first carbon nanotube layer 102 is a plurality of layers of carbon nanotube film or a plurality of interdigitated carbon nanotubes, the plurality of first holes 1 〇 3 are interconnected trench networks. . In step S33, due to the presence of the first carbon nanotube layer 1〇2, lattice dislocations between the epitaxial grains 1042 and the substrate 100 stop growing during the formation of the continuous epitaxial film 1044. Therefore, the first epitaxial layer 104 of this step corresponds to homoepitaxial growth on the surface of the epitaxial film 丨〇44 having no defects. The first epitaxial layer 104 has fewer defects. 100112867 Form No. A0101 Page 17 of 48 1002021430-0 201238887 In the first embodiment of the present invention, the substrate 100 is a sapphire (Al2〇3) substrate, the first carbon nanotube layer 102 is a single layer of carbon nanotube film. This embodiment uses epitaxial growth by MOCVD. Among them, high-purity ammonia (nh3) is used as the source gas of nitrogen, hydrogen (h2) is used as the carrier gas, and trimethylgallium (TMGa) or triethylgallium (TEGa) or trimethylindium (TMIn) is used. Trimethylaluminum (TMA1) acts as a Ga source, an In source, and an A1 source. Specifically includes the following steps

[〇_] First, put the sapphire substrate 100 into the reaction chamber, heat it to 1100 ° C ~ 1 200 ° C, and pass H2, \ or its mixed gas as a carrier gas, high temperature baking 2 0 0 seconds ~ 1 0 0 0 seconds. [0049] Next, continue to pass the carrier gas, and reduce the temperature to 500 ° C ~ 650 ° C, pass through trimethyl gallium or triethyl gallium and ammonia, grow GaN low temperature buffer layer, the thickness of 10 nm ~ 50 Nano. [0050] Then, stop the introduction of trimethyl gallium or triethyl gallium, continue to pass ammonia gas and carrier gas, while raising the temperature to 1100 ° C ~ 1 200 ° c, and maintaining a constant temperature of 30 seconds ~ 3 0 0 seconds, annealing was performed. [0051] Finally, the temperature of the substrate 100 is maintained at 1 000 ° C to 1100 ° C, and the ammonia gas and the carrier gas are continuously introduced, and the tris-gallium or triethyl gallium is re-introduced to complete the GaN at a high temperature. The lateral epitaxial growth process and the growth of a high quality G a N epitaxial layer. [0052] After the samples were grown, the samples were observed and tested by scanning electron microscopy (SEM) and transmission electron microscopy (TEM), respectively. Referring to FIG. 8 and FIG. 9 , in the epitaxial structure prepared in this embodiment, the first epitaxial layer starts to grow only from the position where the epitaxial growth surface of the substrate has no carbon nanotube layer, and then is connected to 100112867, Form No. A0101, page 18 / A total of 48 pages 1002021430-0 201238887 into one. The secret hole,

Interval setting. Ο [0053]

[0054] G

[0055] 100112867 The orientation of the carbon = is related, and the plurality of holes are connected to each other in a plane. Preferably, the plurality of holes are nano-scale holes. Specifically, it is clear from Fig. 8 that the interface between the GaN epitaxial layer and the sapphire substrate is seen, wherein the dark portion is a GaN epitaxial layer and the light portion is a sapphire substrate. The surface of the GaN epitaxial layer in contact with the sapphire substrate has a row of holes. As can be seen from Fig. 9, a carbon nanotube is disposed in each of the holes. The carbon nanotubes in the holes are disposed on the surface of the sapphire substrate and are spaced apart from the GaN epitaxial layer forming the holes. In step S40, the structure, arrangement, formation method, material, and the like of the second carbon nanotube layer 107 are the same as those of the first carbon nanotube layer 102. Therefore, no further description is given here. The second carbon nanotube layer 1 has a plurality of second openings 1〇8, and the plurality of second openings 108 penetrate the second carbon nanotubes from the thickness direction of the second carbon nanotube layer 1〇7 Layer 丨〇 7. When the second carbon nanotube layer 107 covers the surface 106 of the first epitaxial layer 104, the surface 1〇6 of the first epitaxial layer 104 is exposed to a portion corresponding to the second opening 1〇8. In order to grow the second epitaxial layer 109. The second opening 108 can be a microhole or a gap. The second opening 108 is sized and distributed in the same manner as the first opening 105. In the step S50, the second epitaxial layer 1〇9 refers to a single crystal structure grown on the surface 1 of the first epitaxial layer 104 by epitaxial method, and the material thereof may be the same as that of the first epitaxial layer 104. Not the same. The second outer form number A0101, page 19 / total 48 pages 1002021430-0 201238887 The growth method and material of the extension layer 109 can adopt the growth method and material of the Chu-e epitaxial layer 104 of step S2{) T . [0056] [0060] [0060] Referring to FIG. 10, specifically, the second epitaxial layer 1 〇 9 body includes the following steps: The growth process has S51: along the basic Vertically nucleating and epitaxially growing in the direction of the surface 106 of the first epitaxial layer 1() 4 to form a complex number ____ gorge 1092 S52: the complex epitaxial grains 1 092 are substantially parallel to the first The outer surface of the surface of the substrate 100 away from the surface of the substrate 100 is formed by a bite growth - a continuous epitaxial film 1 094; S53: the epitaxial film 1 〇 94 is substantially perpendicular to the substrate 100 away from the substrate 100 The second epitaxial layer 109 is epitaxially grown in the surface 1〇6 direction. The epitaxial layer first-epitaxial layer length forms a step S5lt', and the complex epitaxial grain 1() 92 passes through the second nanocarbon of the first epitaxial layer away from the substrate 1()(4) surface 1()6 The exposed portion of the second opening σ1{)8 of the tube layer 107 begins to grow and its growth direction is substantially perpendicular to the surface 106' of the first epitaxial layer 1G4 away from the substrate 100. That is, the plurality of epitaxial grains 1G92 in this step In the longitudinal epitaxial growth step S 5 2, 'the plurality of epitaxial grains 1092 are along the substantially flat rod by controlling the growth conditions; the first epitaxial layer 104 is homogenous in the direction away from the substrate 1 to 106. Epitaxially growing and integrating to form the second carbon nanotube layer 1〇7. That is, the complex epitaxial grains 1092 in the step are directly closed to epitaxial growth, and finally form a number around the carbon nanotubes. ΗΠ0ΗΠ Page 20 of 48 1002021430-0 201238887 [0062] Ο Two holes 1 0 9 3 surrounded by a broken tube. Preferably, the carbon nanotubes are spaced apart from the second epitaxial layer 109 surrounding the carbon nanotubes. The shape of the hole is related to the arrangement direction of the carbon nanotubes in the second carbon nanotube layer 107. When the second carbon nanotube layer 107 is a single-layer carbon nanotube film or a plurality of parallelly disposed nanocarbon lines, the plurality of second holes 1 093 are substantially parallel disposed grooves. When the second carbon nanotube layer 107 is a plurality of layers of carbon nanotube films or a plurality of interdigitated carbon nanotube circuits, the plurality of second holes 1093 are interposed groove networks. In step S53, due to the presence of the second carbon nanotube layer 107, lattice dislocations between the epitaxial grains 1 092 and the substrate 100 stop growing during the formation of the continuous epitaxial film 1094. Therefore, the second epitaxial layer 109 of this step corresponds to homoepitaxial growth on the surface of the epitaxial film 1094 which is free from defects. The second epitaxial layer 109 has fewer defects. In the first embodiment of the present invention, the second carbon nanotube layer 107 is a single-layer carbon nanotube film. In this embodiment, the second epitaxial layer 109 is epitaxially grown by the MOCVD method. Among them, high-purity ammonia (ΝΗ3) is used as the source gas of nitrogen, hydrogen (Η2) is used as the carrier gas, and trimethylgallium (TMGa) or triethylgallium (TEGa) or trimethylindium (TMIn) is used. Trimethylaluminum (TMA1) is used as a Ga source, an In source, and an A1 source. Specifically, the following steps are included: [0064] First, the substrate 100 on which the first epitaxial layer 104 is grown is placed in a reaction chamber, heated to 1100 ° C to 1 200 ° C, and h2, \ or a mixed gas thereof is used as a carrier gas. , high temperature baking 200 seconds ~ 1 000 seconds. [0065] Next, continue to carry the same carrier gas, and cool down to 500 ° C ~ 650 ° C, through the tri-n-gallium or triethyl gallium and ammonia, grow GaN low-temperature buffer layer, the thickness of 100112867 Form No. A0101 21 pages / total 48 pages 1002021430-0 201238887 for 10 nm ~ 50 nm. [0066] Then 'stop the introduction of trimethyl gallium or triethyl gallium, continue to pass ammonia and carrier gas, while raising the temperature to ll 〇〇 t ~ 1200t, and maintaining the temperature for 30 seconds ~ 300 seconds, annealing. [0067] Finally, the temperature of the substrate 100 on which the first epitaxial layer 104 is grown is maintained at 1000 ° C to 1100 ° C, and the ammonia gas and the carrier gas are continuously supplied, and the germanium or triethyl gallium is re-introduced. The lateral epitaxial growth of GaN is completed at a high temperature, and a higher quality GaN epitaxial layer is grown. [0068] Referring to FIG. 11 and FIG. 12, an epitaxial structure 10 obtained by the first embodiment of the present invention includes: a substrate 1 〇〇, a first carbon nanotube layer 102, and a first epitaxy. The layer 1〇4, a second carbon nanotube layer 7 and a second epitaxial layer 109. The substrate 1 has an epitaxial growth surface. The first carbon nanotube layer 102 is disposed on the epitaxial growth surface 101 of the substrate 1 '. The first carbon nanotube layer 102 has a plurality of first openings 1 〇 5, and the epitaxial growth surface of the substrate 100 A portion of the first opening 1〇5 corresponding to the first carbon nanotube layer 102 is exposed. The first epitaxial layer 1〇4 is disposed on an epitaxial growth surface of the substrate 1 and covers the first carbon nanotube layer 102. The first carbon nanotube layer 1〇2 is disposed between the first epitaxial layer 104 and the substrate 100. The second carbon nanotube layer IQ is disposed on a surface 1〇6 of the first epitaxial layer 104 away from the substrate 1 , and the second carbon nanotube layer 107 has a plurality of second openings 1〇8, The surface 1〇6 of the first epitaxial layer 104 remote from the substrate 100 is exposed to a portion of the second opening 108 of the second carbon nanotube layer 107. The second epitaxial layer 1 is disposed on the surface 1〇6 of the first epitaxial layer 104 away from the substrate ι and covers the second nano-barrier layer 107. The second carbon nanotube layer ι〇7 100112867 Form No. Α0101 Page 22 of 48 201238887 is located between the second epitaxial layer 1〇9 and the first epitaxial layer 104. [0069] 第 the first epitaxial layer 104 covers the first nano-tube layer 1G2 and penetrates the plurality of the first-nano-damage layer 102, and the epitaxial growth of the opening 105 and the substrate 100 The facet 1 contact, that is, the first epitaxial layer 104 is infiltrated into the plurality of first openings 1〇5 of the first nanocarbon layer 102. The first epitaxial layer 1G4 and the covered nano-barrier layer 1〇2 are microscopically spaced apart, that is, the surface of the first epitaxial layer 1〇4 in contact with the substrate 1〇〇 forms a plurality of first holes 1 〇3, the first carbon nanotube layer 1〇2 is disposed in the first hole 103. Specifically, the carbon nanotubes in the first carbon nanotube layer 102 are respectively disposed in the plurality of holes/holes 103. Inside. The first hole 103 is formed on a surface of the first epitaxial layer 1〇4 in contact with the substrate 100, and the first hole Ϊ03 is a blind hole in a thickness direction of the first epitaxial layer 104. In each of the first holes, the carbon nanotubes are substantially not in contact with the first epitaxial layer 104. [0070] ❹ the second epitaxial layer 1〇9 covers the second carbon nanotube layer 107 and penetrates the plurality of second openings 108 of the second carbon nanotube layer 1〇7 and the first The surface 106 of the epitaxial layer 104 remote from the substrate 1 is in contact with the first epitaxial layer 109 in the plurality of second openings 1 〇 8 of the first carbon nanotube layer 107. The second epitaxial layer 1〇9 is microscopically spaced from the second carbon nanotube layer 107 covered by the second epitaxial layer 1〇9, that is, the surface of the second epitaxial layer 1〇9 in contact with the first epitaxial layer 104 forms a plurality of The second carbon nanotube layer 107 is disposed in the second hole 1〇93, and specifically the carbon nanotubes in the second carbon nanotube layer 107 are respectively disposed in plural Inside the second hole 1093. The second hole 1 093 is formed on a surface of the second epitaxial layer 109 that is in contact with the first epitaxial layer ι 4, in the 100112867 Form No. A0101 Page 23 / Total 48 Page 1002021430-0 201238887 First The second holes 1 093 are all blind holes in the thickness direction of the epitaxial layer 104. Within each of the second holes 1 0 9 3 , the carbon nanotubes are substantially not in contact with the second epitaxial layer 109. [0071] The first carbon nanotube layer 102 and the second carbon nanotube layer 107 are both self-supporting structures. The carbon nanotube layer comprises a carbon nanotube membrane or a nanocarbon pipeline. In this embodiment, the first carbon nanotube layer 102 and the second carbon nanotube layer 107 are respectively a single-layer carbon nanotube film, and the carbon nanotube film comprises a plurality of carbon nanotubes. The axial direction of the plurality of carbon nanotubes extends in a preferred orientation in the same direction, and adjacent carbon nanotubes extending in the same direction are connected end to end by van der Waals force. Micropores or gaps are provided at intervals between adjacent carbon nanotubes perpendicular to the extending direction to constitute a first opening 105 and a second opening 108. Referring to FIG. 13, an epitaxial structure 20 prepared according to a second embodiment of the present invention includes: a substrate 100, a first carbon nanotube layer 102, and a first epitaxial layer 104'. The carbon nanotube layer 107 and a second epitaxial layer 109. The material of the first epitaxial layer 104 and the second epitaxial layer 109 of the epitaxial structure 20 in the second embodiment of the present invention, and the substrate 100, the first carbon nanotube layer 102, the first epitaxial layer 104, and the second nanometer The positional relationship between the carbon tube layer 1 〇7 and the second epitaxial layer 109 is substantially the same as that of the epitaxial structure 10 of the first embodiment, except that the first carbon nanotube layer 102 and the second carbon nanotube layer 107 is composed of a plurality of parallel and spaced carbon nanotubes, and micropores are formed between adjacent nanocarbon lines. [0073] The nanocarbon line may be a non-twisted nanocarbon line or a twisted nanocarbon line. Specifically, the non-twisted nanocarbon line includes a plurality of carbon nanotubes extending along the length of the non-twisted nanocarbon line. The 100112867 form number A0101 page 24 / total 48 page 1002021430-0 201238887 [0074] [0075]

The twisted nanocarbon line includes a plurality of carbon nanotubes extending axially around the twisted nanocarbon line. In addition, in the embodiment, the substrate 100 is a silicon-on-insulator (SOI) substrate. In the present embodiment, the first epitaxial layer 104 is epitaxially grown by the M0CVD method. Among them, tricarbyl gallium (TMGa) and trisyl aluminum (TMA1) are used as the source materials of Ga and A1, ammonia (NH3) is used as the source of nitrogen, hydrogen (H2) is used as carrier gas, and horizontal level is used. The furnace is heated. Specifically, a plurality of parallel and spaced carbon nanotube lines are first laid on the epitaxial growth surface 101 of the SOI substrate 100. Then, a GaN epitaxial layer is epitaxially grown on the epitaxial growth surface 101 of the substrate 100, the growth temperature is 1070 ° C, and the growth time is 450 seconds, mainly for longitudinal growth of GaN; then, the pressure of the reaction chamber is kept constant, and the temperature is raised to 1110 ° C. At the same time, the Ga source flow rate is reduced, while the ammonia gas flow rate is kept constant to promote lateral epitaxial growth, and the growth time is 4900 seconds. Finally, the temperature is lowered to 1070 ° C, and the Ga source flow rate is increased to continue longitudinal growth for 1 0000 seconds. Referring to FIG. 14 , a third embodiment of the present invention provides an epitaxial structure 30 including a substrate 100 , a first carbon nanotube layer 102 , a first epitaxial layer 104 , and a second carbon nanotube layer . 107 and a second epitaxial layer 109. The substrate 100, the material of the first epitaxial layer 104 and the second epitaxial layer 109 of the epitaxial structure 30 in the third embodiment of the present invention, and the substrate 100, the first carbon nanotube layer 102, the first epitaxial layer 104, The positional relationship between the second carbon nanotube layer 107 and the second epitaxial layer 109 is substantially the same as that of the epitaxial structure 10 of the first embodiment, except that the first carbon nanotube layer 102 and the second carbon nanotube layer 107 are different. Each consists of a plurality of carbon nanotubes that are interdigitated and spaced apart, and micropores are formed between the intersecting and adjacent four nanocarbon lines. Form No. A0101, page 25 of 48, 1002021430-0 201238887. Specifically, the plurality of carbon nanotubes are respectively disposed in parallel with the second direction in the first direction, and the first direction is disposed to intersect the second direction. An opening is formed between the four adjacent carbon carbon lines that are adjacent to each other. In this embodiment, two adjacent nanocarbon pipelines are arranged in parallel, and the two nanocarbon pipelines intersecting each other are perpendicular to each other. It can be understood that the nano carbon pipeline is also arranged in any way, and only the first carbon nanotube layer 1〇2 and the second carbon nanotube layer 107 are respectively formed into a plurality of openings, so that the substrate 1〇 The epitaxial growth surface of the epitaxial layer 1〇4 may be partially exposed. The epitaxial structure 30 of the third embodiment of the present invention can be produced by the same method as the first embodiment or the second embodiment. A fourth embodiment of the present invention provides a plurality of epitaxial structures including a substrate, a plurality of carbon nanotube layers, and a plurality of epitaxial layers. The carbon nanotube layer in the fourth embodiment of the present invention may adopt the carbon nanotube layer of the first embodiment to the third embodiment, the material and the positional relationship between the substrate, the carbon nanotube layer and the epitaxial layer. The first embodiment is substantially the same, except that the epitaxial structure of the present embodiment includes a plurality of stacked epitaxial layers, and an epitaxial growth surface of the substrate and a carbon nanotube layer are disposed between each adjacent epitaxial layer. The fourth embodiment of the present invention further provides a method for preparing a plurality of epitaxial structures, which specifically includes the following steps: [0079] Step 1. Providing a substrate and having an epitaxial growth surface supporting epitaxial layer growth [0080] Step 2: providing a carbon nanotube layer on the epitaxial growth surface of the substrate, the substrate and the carbon nanotube layer together forming a substrate; 100112867 Form No. A0101 Page 26 / Total 48 Page 1002021430 -0 201238887 [0081] Step 3 [0082] Step 4 [0083] Step 5 [0084] Step 6 Carbon tube layer; [0085] Step 7 Epitaxial layer; Growth of the first epitaxial growth surface of the substrate Layer; surface of the first epitaxial layer a carbon nanotube layer is disposed; a second epitaxial layer is grown on the surface of the first epitaxial layer; and a surface of the second epitaxial layer remote from the first epitaxial layer is provided on the surface of the second epitaxial layer away from the first epitaxial layer [0086] Step S: providing a carbon nanotube layer on the surface of the η epitaxial layer away from the epitaxial layer n-1; [0088] Step S+1: in the η epitaxial The n + 1 epitaxial layer of the layer is grown away from the surface of the epitaxial layer n-1. Wherein S is an integer greater than or equal to 8, and η is an integer greater than or equal to 3. [0090] The growth method of each epitaxial layer of the fourth embodiment of the present invention is substantially the same as the growth method of the epitaxial layer of the first embodiment. [0091] It can be understood that the second to n-layer epitaxial layers are sequentially stacked and grown on the surface of the first epitaxial layer, and a photomask layer is disposed between each adjacent epitaxial layer, and at least one photomask layer in the photomask layer is Carbon nanotube layer. When the nth epitaxial layer is grown, the surface of the n-1th epitaxial layer away from the n-2th epitaxial layer may be provided with, for example, a patterned process, in addition to the carbon nanotube layer being used as a photomask layer. Wait for other mask layers. [0092] The present invention uses a carbon nanotube layer as a mask to be disposed on the substrate epitaxial 100112867. Table No. A0101 Page 27 / Total 48 Page 1002021430-0 201238887 The growth surface growth epitaxial layer has the following effects: [0093] The _, the carbon nanotube layer is a self-supporting structure that can be directly laid on the epitaxial growth surface of the substrate, and the reticle is formed by a manufacturing method such as post-deposition lithography with respect to the prior art, and the process of the invention is simple and low-cost It is conducive to mass production. [0094] Second, the carbon nanotube layer is a patterned structure, and the thickness and the opening size thereof can reach a nanometer level, and the epitaxial grains formed when the substrate is used to grow the epitaxial layer have a smaller ruler. <, it is advantageous to reduce the generation of dislocation defects to obtain a high quality epitaxial layer. [0095] Third, the carbon nanotube layer has an opening size up to the nanometer level, and the epitaxial layer is grown from the exposed epitaxial growth surface corresponding to the nanometer opening, so that the grown epitaxial layer and the substrate are between The contact area is reduced, and the stress between the epitaxial layer and the substrate during the growth process is reduced, so that the epitaxial layer having a larger thickness can be grown, and the quality of the epitaxial layer can be further improved. [0096] Fourth, by setting the carbon nanotube film multiple times and epitaxially growing the epitaxial layer multiple times, defects in the epitaxial layer can be further reduced, and the quality of the epitaxial layer can be improved. [0097] In summary, the present invention has indeed met the requirements of the invention patent, and the patent application is filed according to law. However, the above description is only a preferred embodiment of the present invention, and it is not possible to limit the scope of the patent application of the present invention. Equivalent modifications or variations made by those skilled in the art will be encompassed within the scope of the following claims. BRIEF DESCRIPTION OF THE DRAWINGS [0098] FIG. 1 is a flow chart showing a manufacturing method of a method for fabricating an epitaxial structure according to an embodiment of the present invention. 100112867 Form No. A0101 Page 28/Total 48 Page 201238887 [0099] FIG. 2 is a scanning electron micrograph of a carbon nanotube film used in an embodiment of the present invention [0100] FIG. 3 is a carbon nanotube film of FIG. Schematic diagram of the structure of the carbon nanotube fragments in the middle. 4 is a scanning electron micrograph of a carbon nanotube film disposed at a plurality of layers in an embodiment of the present invention. 5 is a scanning electron micrograph of a non-twisted nanocarbon line used in an embodiment of the present invention. Figure 6 is a scanning electron micrograph of a twisted nanocarbon line used in an embodiment of the present invention. 7 is a schematic view showing a growth process of a first epitaxial layer in an embodiment of the present invention. 8 is a scanning electron micrograph of a cross section of an epitaxial structure prepared in accordance with a first embodiment of the present invention. 9 is a transmission electron micrograph at the interface of the epitaxial structure prepared in the first embodiment of the present invention. 10 is a schematic view showing a growth process of a second epitaxial layer in an embodiment of the present invention. 11 is a perspective view showing the three-dimensional structure of an epitaxial structure according to a first embodiment of the present invention. 12 is a schematic cross-sectional view of the epitaxial structure shown in FIG. 11 taken along line X11 - X11. 13 is a perspective view showing a perspective structure of an epitaxial structure according to a second embodiment of the present invention. 100112867 Form No. A0101 Page 29 of 48 1002021430-0 201238887 [0111] FIG. 14 is a perspective view showing a three-dimensional structure of an epitaxial structure according to a third embodiment of the present invention. [Explanation of main component symbols] [0112] Epitaxial structure: 10, 20, 30 [0113] Substrate: 100 [0114] Epitaxial growth surface: 101 [0115] First carbon nanotube layer: 102 [0116] First hole : 1 0 3 [0117] First epitaxial layer: 104 [0118] First opening: 1 0 5 [0119] Surface: 106 [0120] Second carbon nanotube layer: 107 [0121] Second opening: 108 [ 0122] Second epitaxial layer: 109 [0123] Epitaxial grain: 1042 [0124] Epitaxial film: 1044 [0125] Epitaxial grain: 1092 [0126] Second hole: 1093 [0127] Epitaxial film: 1094 [0128] Carbon tube fragment: 143 1002021430-0 100112867 Form number A0101 Page 30 of 48 145 201238887 [0129] Nano carbon tube

100112867 Form No. A0101 Page 31 of 48 1002021430-0

Claims (1)

201238887 VII. Patent application scope: 1. A method for preparing an epitaxial structure, comprising the steps of: providing a substrate having an epitaxial growth surface; and providing a first carbon nanotube layer on an epitaxial growth surface of the substrate Forming a first epitaxial layer on the epitaxial growth surface of the substrate and covering the first carbon nanotube layer; and providing a second carbon nanotube layer on a surface of the first epitaxial layer, wherein the The surface of an epitaxial layer is an epitaxial growth surface of the first epitaxial layer; and a second epitaxial layer is grown on the surface of the first epitaxial layer and covers the second carbon nanotube layer. 2. The method of preparing a structure according to claim 1, wherein the first epitaxial layer is a heteroepitaxial layer. 3. The method according to claim 1, wherein the substrate is a single crystal structure, and the material of the substrate is GaAs 'GaN, Si, SOI, AIN, SiC, MgO, ZnO 'LiGa〇2, LiA102 or Al2〇3. 4. The method for preparing an outer structure according to the first aspect of the invention, wherein the method of providing a carbon nanotube layer on an epitaxial growth surface of the substrate or a surface of the first epitaxial layer is a carbon nanotube The film or nano carbon line is directly laid on the epitaxial growth surface of the substrate as a carbon nanotube layer. 5. The method according to claim 1, wherein the carbon nanotube layer has a plurality of openings, and the first epitaxial layer or the second epitaxial layer is from the epitaxial growth surface. The portion exposed through the opening grows 1002021430-0 100112867 Form No. A0101 Page 32 / Total 48 Page 201238887 6. As claimed in the patent scope! The growth process of the first epitaxial layer or the second epitaxial layer is smothered in the following steps: 戒 nucleation of a plurality of epitaxial grains in a direction perpendicular to the epitaxial growth surface The plurality of epitaxial grains are grown along a substantially parallel epitaxial thin film extending substantially parallel to the epitaxial growth surface; and the epitaxial film is formed along a length substantially perpendicular to the epitaxial growth surface An epitaxial layer. The method for growing the first or second epitaxial layer, the chemical beam exfoliation method, the decompression surgery, the low temperature external one, the permeation (10) fist gas, the liquid, is as described in the application of the full-time enclosure. Phase deposition epitaxy, metal organic vapor phase epitaxy, super-true: vapor phase deposition, hydride vapor phase epitaxy, and metal organic deposition method In the preparation method of the outer structure ship according to the sixth aspect of the patent application scope, the first or second epitaxial layer is in the section; the strip meter travels wide circumference 9.10.11. The nano-tubes in the carbon nanotube layer are described. The method for preparing a composition according to the above-mentioned item (4), wherein the first epitaxial layer or the second epitaxial layer has a wide heteroepitaxial extension. The outer structure according to claim 1, wherein the carbon nanotube material is a self-cutting structure. The method for preparing an outer structure according to the first aspect of the invention, wherein the carbon nanotube layer is disposed on the epitaxial growth surface, further comprising treating the carbon nanotube layer with an organic solvent to form a carbon nanotube The layer is more closely attached to the epitaxial growth surface. 100112867 Form No. A0101 Page 33 of 48 1002021430-° 201238887 12. A method of preparing an epitaxial structure, comprising the steps of: providing a substrate having an epitaxial growth surface; epitaxial growth on the substrate Forming a mask layer on the surface; growing a first epitaxial layer on the epitaxial growth surface of the substrate and covering the surface of the first epitaxial layer of the photomask layer to sequentially grow the second to nth epitaxial layers, each adjacent two epitaxial layers A photomask layer is disposed therebetween; wherein η is an integer greater than or equal to 3, and at least one of the photomask layers is a carbon nanotube layer. 100112867 Form Number Α0101 Page 34 of 48 1002021430-0