TW201239949A - A substrate with micro-structure and method for making the same - Google Patents

Abstract

The present invention relates to a substrate with micro-structure and a method for making the same. The method includes following steps: providing a substrate with a surface for epitaxial growth; growing a buffer layer on the surface; disposing a carbon nanotube layer on the buffer layer; growing an epitaxial layer on the buffer layer; and removing the substrate.

Description

201239949 * VI. DESCRIPTION OF THE INVENTION: TECHNICAL FIELD [0001] The present invention relates to a substrate having a microstructure and a method of fabricating the same. [Prior Art] [0002] A micro-structured substrate formed of a nitride mainly composed of GaN, InGaN, or AlGaN is a semiconductor structure that has been attracting attention in recent years, and has a direct band gap with variable performance, and excellent physical and chemical stability. Characteristics such as high saturation electron mobility make it a preferred semiconductor structure for optoelectronic devices and microelectronic devices such as lasers and light-emitting diodes. 〇 _] Due to the limitations of GaN and other growth techniques, the prior art towel has a large area.

Most of the GaN semiconductor layers are grown on other substrates such as sapphire. Due to the different lattice constants of the gallium nitride and sapphire substrates, there are many dislocation defects in the gallium nitride epitaxial layer. The prior art provides a method for improving the above-mentioned deficiencies by epitaxially growing gallium nitride on a non-flat sapphire substrate. However, the prior art generally uses a microelectronic fabrication method such as photolithography to form a trench on the surface of the sapphire substrate to form a non-tanned epitaxial growth surface. The method not only has a complicated manufacturing process, but also has high cost, and pollutes the epitaxial growth surface of the sapphire substrate, thereby affecting the quality of the epitaxial structure. SUMMARY OF THE INVENTION [0004] There is a method for preparing a micro-structured substrate which is simple in manufacturing method, low in cost, and does not cause contamination on the surface of the substrate, and a widely used micro-structured substrate. It is really necessary. [0005] A method for preparing a substrate having a microstructure, comprising the steps of: 100112849 providing a sapphire substrate having an epitaxial growth surface form number A0101 Page 3 of 41 page 1002021407-0 201239949 [0006] [0009] [0010] 100112849; growing a low temperature GaN buffer layer on the epitaxial growth surface of the substrate; providing a carbon nanotube layer on the surface of the buffer layer away from the substrate; Forming a GaN epitaxial layer from the surface of the buffer layer; and removing the substrate, a method for preparing a microstructured substrate, comprising the steps of: providing a substrate, the substrate having an epitaxial growth surface; a buffer layer is grown on the epitaxial growth surface of the substrate; a carbon nanotube layer is disposed on the surface of the buffer layer; an epitaxial layer is grown on the surface of the buffer layer provided with the carbon nanotube layer; and the substrate is removed. a micro-structured substrate comprising a semiconductor epitaxial layer and a carbon nanotube layer, wherein a surface of the semiconductor epitaxial layer has a plurality of grooves to form a patterned surface, and the carbon nanotube layer is disposed on the substrate A patterned surface of the semiconductor epitaxial layer and embedded in the semiconductor epitaxial layer. Compared with the prior art, the micro-structured substrate provided by the present invention and the preparation method thereof use the carbon nanotube layer as a mask to grow the epitaxial layer, which greatly reduces the preparation cost of the micro-structured substrate, and the nai The carbon nanotube layer has good electrical conductivity, making the micro-structured substrate have a wide range of uses. [Embodiment] Hereinafter, a substrate having a microstructure and a method for fabricating the same according to embodiments of the present invention will be described in detail with reference to the accompanying drawings. Referring to FIG. 1 , a first embodiment of the present invention provides a method for fabricating a substrate 10 having a microstructure. The method further includes the following steps: S11, providing a substrate 1 〇〇, and the substrate 100 having a supporting epitaxial form number A0101 4 pages/total 41 pages 002021407^ [0011] 201239949 long epitaxial growth surface 101; 12 a buffer layer 1 〇41 is grown on the epitaxial growth surface of the substrate 1〇〇; [0013] Sl3 'in the buffer layer The surface of 1〇41 is provided with a carbon nanotube layer 1〇2; [〇〇14] Sl4′ is grown on the surface of the buffer layer 1041 provided with the carbon nanotube layer 102 _ epitaxial layer 104; [] S15, removing the Substrate, the substrate having the microstructure is obtained [0016]

100112849 In step S11, the substrate 1〇〇 provides an extended epitaxial layer 101 outside the epitaxial layer 1〇4. The epitaxial growth surface 1〇1 of the substrate 1为 is a molecularly smooth surface' and impurities such as oxygen or carbon are removed. The substrate 丨〇〇 may be a single layer or a plurality of layers. When the substrate 1 is a single layer structure, the substrate 1〇〇 may be a single crystal structure and have a crystal plane as the epitaxial growth surface 101 of the epitaxial layer 1〇4. The material of the single layer structure of the substrate 丨00 may be GaAs,

GaN, Si, SOI (Silicon-On-Insulator), AIN, SiC, MgO, ZnO, LiGa〇2, LiA1〇2 or ^2〇3, and the like. When the substrate 100 is a plurality of layers, it needs to include at least one layer of the above single crystal structure, and the single crystal structure has a crystal plane as an epitaxial layer called an epitaxial growth surface. The epitaxial layer 104 to be grown is selected, preferably, the substrate 1 〇〇 has an adjacent lattice constant and thermal expansion coefficient of the epitaxial layer 1 〇 4, and the thickness, size and shape of the substrate (10) are not limited. Need to choose. The substrate (10) is not limited to the materials listed above, as long as the base state of the epitaxial growth surface m supporting the epitaxial layer is within the protection range of the present invention. In the embodiment, the material of the substrate 100 is Ai 〇. Form No. A0101 Page 5 of 41 1002021407-0 201239949 [〇〇17] In step S12, the growth method of the buffer layer 1041 can be respectively performed by molecular beam epitaxy (MBE), chemical beam epitaxy (CBE), Decompression epitaxy, 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 One or more of HVPE), metal organic chemical vapor deposition (MOCVD), etc. The material of the buffer layer 1041 may be Si, GaAs, GaN, GaSb, InN, InP, InAs, InSb, A1P, AlAs, AlSb, AIN, GaP,

SiC, SiGe, GaMnAs, GaAlAs, GalnAs, GaAIN, GalnN 'AlInN, GaAsP, InGaN, AlGalnN, AlGalnP, GaP: Zn or GaP: N. When the material of the buffer layer 104 is different from the material of the substrate loo, the growth method is called heteroepitaxial growth. When the material of the buffer layer 1041 can be the same as the material of the substrate 100, the growth method is called homoepitaxial growth. In the first embodiment of the present invention, the epitaxial growth buffer layer 1041 is performed by an MOCVD process. Among them, high-purity ammonia gas (κυρ is used as the source gas of nitrogen, hydrogen gas (h2) is used as carrier gas, and trimethylgallium (TMGa) or triethylgallium (TEGa), trimethylindium (TMIn), and three are used. Methyl aluminum (TMA1) is used as a Ga source, an In source, and an A1 source. The growth of the buffer layer 1〇41 specifically includes the following steps: [0019] First, the sapphire substrate 100 is placed in a reaction chamber and heated to 11 Torr.匚~1200 C, and pass H2, \ or its mixed gas as carrier gas, and bake at high temperature for 200 seconds~1 sec. [0020]

Secondly, 'continue to pass the carrier gas and cool down to 500 ° c ~ 65 (rc, pass through trimethyl gallium or triethyl gallium and ammonia, low temperature growth of GaN layer, the low temperature GaN 100112849 form number A0101 page 6 / Total 41 pages 1002021407-0 201239949 [0021] Ο [0022]

The layer serves as a buffer layer 1041 for continuing to grow the epitaxial layer 104, and has a thickness of 10 nm to 50 nm. Since the GaN epitaxial layer 104 and the sapphire substrate 100 have different lattice constants, the buffer layer 1041 serves to reduce lattice mismatch during the growth of the epitaxial layer 104, and reduce the bit error density of the grown epitaxial layer 104. . In step S13, the carbon nanotube layer 102 is disposed on a surface of the buffer layer 1041 away from the substrate 100. The carbon nanotube layer 102 is placed in contact with the buffer layer 1041. The carbon nanotube layer 102 includes a plurality of carbon nanotubes extending in a direction substantially parallel to the surface of the carbon nanotube layer 102. When the carbon nanotube layer 102 is disposed on the surface of the buffer layer 1041, the plurality of carbon nanotubes in the carbon nanotube layer 102 extend substantially parallel to the surface of the buffer layer 1041. The carbon nanotube layer 102 has a plurality of openings 105 through which the buffer layer 1041 is partially exposed. The carbon nanotube layer 102 is a continuous overall structure comprising a plurality of carbon nanotubes. The carbon nanotube layer 102 is a macrostructure. Further, the carbon nanotube layer 102 is a self-supporting structure. By "self-supporting", the carbon nanotube layer 102 does not require a large area of carrier support, but can maintain its own state by simply providing a supporting force on both sides, that is, placing the carbon nanotube layer 102 (or When fixed to two supports disposed at a certain distance apart, the carbon nanotube layer 102 located between the two supports can be suspended to maintain its own state. Since the carbon nanotube layer 102 is a self-supporting structure, the carbon nanotube layer 102 can be directly disposed on the surface of the buffer layer 1041 by a laying method, and the surface of the buffer layer 1041 can be disposed without complicated steps. The formation of a uniform carbon nanotube layer 102 is simple and controllable, and is advantageous for mass production in a large-scale mass production of 100112849 Form No. A0101, Page 7 of 41, 1002021407-0 201239949. Preferably, the carbon nanotube layer 1〇2 is a pure carbon nanotube structure composed of a plurality of carbon nanotubes. The term "pure carbon nanotube structure" means that the carbon nanotube layer does not require any chemical modification or acidification treatment throughout the preparation process, and does not contain any functional group modification such as a carboxyl group. The plurality of carbon nanotubes in the nano-reverse layer 102 extend in a direction substantially parallel to the surface of the carbon nanotube layer 102. [0023] When the carbon nanotube layer 102 is disposed on the buffer layer 1〇41, the plurality of carbon nanotubes in the carbon nanotube layer 102 extend substantially parallel to the buffer layer 1041. The carbon nanotube layer has a thickness of from 1 nm to 1 μm, or from 1 nm to 1 μm, or from 1 nm to 200 nm, preferably from 〇 nm to 100 nm. The carbon nanotube layer 1〇2 is a patterned nanocarbon layer 102. The "patterning" means that the carbon nanotube layer 1 〇 2 has a plurality of openings 105 penetrating the carbon nanotubes from the thickness direction of the carbon nanotube layer 1 〇 2 Layer 1〇2. The opening 1〇5 may be a micro hole or a gap. The size of the opening 105 is 1 〇 nanometer to 5 〇〇 micrometer, and the size refers to the aperture of the micro hole or the pitch of the gap in the width direction. The size of the opening 105 is from 1 nanometer to 300 micrometers, or from 1 nanometer to 120 micrometers, or from 1 nanometer to 80 micrometers, or from 1 nanometer to 1 micrometer. The smaller the size of the opening 105 is, it is advantageous to reduce the occurrence of misalignment defects during the growth of the epitaxial layer ι 4 to obtain a high-quality epitaxial layer 1 〇 4. Preferably, the size of the opening 105 is from 1 nanometer to 10 micrometers. Further, the duty ratio of the carbon nanotube layer 102 is ι··ι〇〇~ι〇0:ι, or noqo:;!, or 1:2, 2:1, or 1:4~4 :1. Preferably, the duty ratio is 1: 4 to 4:1. The term "duty cycle" means that the carbon nanotube layer 1 〇 2 is disposed after the buffer layer 1041, and the carbon nanotube layer ι 2 is occupied by the buffer layer 1 〇 41. The part number is A1121. Page 41, 1002021407-0, 201239949 The area ratio of the portion exposed to the buffer layer 1041 through the opening 1〇5 [0024] [0025] [0026] The patterning described in the 'step' refers to the The carbon nanotube layer 10 is a number of carbon nanotubes in the state of the way of riding, and there are specifications. For example, the intermediate carbon nanotubes in the carbon nanotube layer 102 are all in the axial direction, and the buffer layer is '~'. 1041 and extending substantially in the same direction. In the above, the axial direction of the plurality of carbon nanotubes in the carbon nanotube layer 102 can be regularly extended in two or more directions. Adjacent carbon nanotubes extending in the same direction in the tube layer 1〇2 are connected end to end by a van de Waals force. The nanocarbon layer 102 has an opening 1 as described above. Under the premise of 〇5, the plurality of carbon nanotubes in the carbon nanotube layer 102 may also be randomly arranged and randomly arranged. The carbon nanotube layer 1〇2 The carbon nanotube tube may be one or a plurality of single-walled carbon nanotubes, double-walled carbon nanotubes or multi-millimeter carbon tubes, and the length and direct control thereof may be selected according to requirements. As a mask in the growth epitaxial layer 1〇4, the phrase “mask A refers to the epitaxial layer 104 grown to the height at which the carbon nanotube layer 1〇2 is located, only from the opening 1Q5 of the carbon nanotube layer 102. Grow outward. Since the carbon nanotube layer 1G2 has a plurality of openings 1 () 5, the carbon nanotube layer 1 〇 2 forms a patterned mask. When the carbon nanotube layer 1〇2 is disposed in the buffer of the Tang 1〇41, the plurality of carbon nanotubes may extend in a direction parallel to the surface of the buffer layer 1〇41. The nanocarbon (4) 1Q2 may also include a composite structural layer comprising a plurality of nylon tubes and an additive material. The additive material includes a graphite, a graphite thinner, a carbonized sphere, a nitrided hair, a dioxic cut, an amorphous carbon, and the like. 100112849 Form No. A0101 Page 9 / Total 41 Page 1002021407-0 [0027] 201239949 Kind or plural. The additive material may further include one or more of metal carbides, metal oxides, metal nitrides, and the like. The additive material is coated on at least a part of the surface of the carbon nanotube in the carbon nanotube layer 1 () 2 or in the opening σ 1 () 5 of the carbon nanotube layer 1 〇 2 . Preferably, the additive material is coated on the surface of the carbon nanotube. Since the additive material is coated on the surface of the carbon nanotube, the diameter of the carbon nanotube is made larger, so that the opening 1〇5 of the carbon nanotube is reduced. The additive material may be formed on the surface of the carbon nanotube by chemical vapor deposition (CVD), physical vapor deposition (PVD), magnetron sputtering or the like. [0029] Further, after the carbon nanotube layer 102 is laid on the surface of the buffer layer 1041, the carbon nanotube layer 102 may be further treated with an organic solvent, and the organic solvent is used for volatilization. The generated surface tension causes the adjacent carbon nanotubes in the carbon nanotube layer 102 to be partially bundled, and further the carbon nanotubes in the nanotube layer 102 are in close contact with the buffer layer. To increase the mechanical strength and adhesion stability of the carbon nanotube layer 102. The organic solvent of 5 kel can be selected from one or a combination of ethanol, methanol, propylene carbonate, ethylene bromide and gas. The organic solvent in this embodiment is ethanol. The step of treating with an organic solvent may immerse the organic solvent in a test tube to wet the entire carbon nanotube layer 1 〇 2 on the surface of the nanotube layer 10 2 or immerse the entire carbon nanotube layer 102 in a container containing an organic solvent. Infiltration. Specifically, the nano-tube layer 102 may include a carbon nanotube film or a nanocarbon line. The carbon nanotube layer 102 can be a single layer of carbon nanotube film or a plurality of stacked carbon nanotube films. The carbon nanotube layer 102 may comprise a plurality of parallel carbon nanotubes disposed in parallel with a plurality of carbon nanotubes or a plurality of carbon nanotubes. When the 100112849 Form No. A0101 Page 10 / Total 41 Page 1002021407-0 201239949 Ο [0030] When the carbon nanotube layer 102 is a plurality of stacked carbon nanotube membranes, the number of layers of the carbon nanotube film should not be too More preferably, it is from 2 layers to 100 layers. When the carbon nanotube layer 102 is a plurality of carbon nanotubes arranged in parallel, the distance between adjacent two nanocarbon lines is 0.1 micron to 200 micrometers, preferably 10 micrometers to 1 00. Micron. The space between the adjacent two nanocarbon lines constitutes the opening 105 of the carbon nanotube layer 102. The carbon nanotube film or the nano carbon line may be a self-supporting structure, and the carbon nanotube layer 102 may be directly formed on the surface of the buffer layer 1041. The size of the opening 105 in the carbon nanotube layer 102 can be controlled by controlling the number of layers of the carbon nanotube film or the distance between the carbon nanotubes.

The carbon nanotube membrane is a self-supporting structure composed of a plurality 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, most of the carbon nanotubes in the carbon nanotube membrane 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 100112849 Form No. Α0101 Page 11 / Total 41 Page 1002021407-0 201239949 can be suspended to maintain its own membranous 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. [0031] 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, it is not possible to exclude partial contact between the carbon nanotubes juxtaposed in the majority of the carbon nanotube membranes extending substantially in the same direction. Referring to FIG. 2 and FIG. 3, in particular, the carbon nanotube film includes a plurality of continuous and oriented extended 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 an opening 105, and the pore size or gap of the micropore 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 document "Nano Carbon Tube Film" of the Republic of China No. 1327177, which was filed on February 12, 2010 by the applicant. Form 100112849 Form No. A0101 Page 12 of 41 Page 1002021407-0 201239949 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. [0033] 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 The angle α is crossed, and α is greater than or equal to 0 degrees and less than or equal to 90 degrees (0. Each α $90.) [0034] Ο

In order to reduce the thickness of the carbon nanotube film, the carbon nanotube film may be further heat treated. 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, the method comprises the steps of: locally heating the carbon nanotube film, so that a part of the carbon nanotube film is oxidized at a local position; and moving the carbon nanotube to be locally heated, from the local to the whole Heating of the carbon nanotube film. Specifically, the method of dividing the carbon nanotube film into a plurality of small regions and heating the carbon nanotube film layer by region from a local to the whole manner may have a plurality of methods for locally heating the carbon nanotube film. Kinds, such as laser heating, microwave heating, etc. Specifically, the carbon nanotube film can be irradiated by a laser scan having a power density greater than l. lx 1 〇 4 watts/m 2 to heat the carbon nanotube film locally to the whole. The carbon nanotube film is irradiated by laser 'partially, the carbon nanotubes are oxidized in the thickness direction, and at the same time, the larger diameter carbon nanotube bundles in the carbon nanotube film are removed', so that the carbon nanotube film becomes thin. [0035] It can be understood that the above method of recording a scanning carbon nanotube film is limited as long as the nanotube film can be uniformly irradiated. The mis-scanning can be performed row by row in the direction of the column of the nanotubes in the parallel carbon nanotube film, or in the direction perpendicular to the arrangement of the nanotubes in the carbon nanotube film. With 100112849 Form No. A0101 Page 13 of 41 1002021407-0 201239949 The lower the speed of a fixed-power, fixed-wavelength laser-scanned carbon nanotube film, the more heat absorbed by the nanotube bundle in the carbon nanotube film More, the more the carbon nanotube bundles corresponding to the destruction, the smaller the thickness of the carbon nanotube film after the laser treatment. However, if the laser scanning speed is too small, the carbon nanotube film will absorb too much heat and be burned. 5秒。 The laser light irradiation time is less than 1.8 seconds. The laser light irradiation 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 micrometers, a spot diameter of 3 mm, and a relative movement speed of the laser device and the carbon nanotube film of less than 10 mm. /second. [0036] The nanocarbon line may be a non-twisted nanocarbon line or a twisted nanocarbon line. The non-twisted nanocarbon pipeline and the twisted nanocarbon pipeline 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〜100微米。 The non-twisted nano carbon line length is not limited, the diameter is 0. 5 nanometers ~ 100 microns. The non-twisted nanocarbon line is obtained by treating the carbon nanotube film described in Fig. 2 above 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 film into a non-twisted nano 100112849 Form No. A0101 Page 14 of 41 1002021407-0 201239949 [0037] ❹

[0039] A carbon line. The organic solvent is a volatile organic solvent such as ethanol, methanol, acetone, di-ethane or gas. 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. The twisted nanocarbon line is obtained by twisting both ends of the carbon nanotube film shown in Fig. 2 in the direction in which the carbon nanotube is extended in the opposite direction 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, and each of the carbon nanotube segments includes a plurality of parallel and through van der Waals Tightly bonded carbon nanotubes. 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 micrometers. 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. For the nano carbon pipeline and its preparation method, please refer to the Republic of China patent No. 1303239, filed on November 5, 2008, filed by the applicant on November 5, 2002. Applicant: Hon Hai Precision Industry Co., Ltd. And the application for the Republic of China patent No. 1 312337, which was filed on December 16, 2005, was filed on July 21, 2009. Applicant: Hon Hai Precision Industry Co., Ltd. It can be understood that the substrate 100, the buffer layer 1041, and the carbon nanotube layer 102 100112849 form number A0101 page 15/41 page 1002021407-0 201239949 together constitute a substrate for growing the epitaxial layer 1〇4. [0042] [0042] Step S14, the growth method of the 1 () 4 can be passed through molecular beam epitaxy & CMBE), chemical beam epitaxy (GBE), decompression epitaxy, low temperature epitaxy Method, selective epitaxy, liquid phase deposition epitaxy αρΕ), metal organic vapor phase epitaxy (_PE), ultra-vacuum chemical vapor deposition (UHVCVD), hydride vapor phase epitaxy (HvpE), and metal organic chemical gas One or more of the phase deposition methods (MOCVD) and the like may be implemented, and the material of the epitaxial layer 104 may be the same as or different from the material of the buffer layer i〇41. The thickness of the growth of the epitaxial layer 104 can be prepared as needed. Specifically, the thickness of the epitaxial layer 104 may be 〇, 5 nm to 丨 mm. For example, the thickness of the epitaxial layer 1〇4 may be from 1 nanometer to 5 nanometers, or from 200 nanometers to 200 micrometers or from 500 nanometers to 1 micrometer. The material of the epitaxial layer 104 is a semiconductor material such as Si, GaAs, GaN, GaSb,

InN, InP, InAs, InSb, A1P, AlAs, AlSb, AIN,

GaP , SiC , SiGe , GaMnAs , GaAlAs , GalnAs , GaAIN ' GalnN ' AlInN ' GaAsP ' InGaN ' AlGalnN ' Al-GalnP, GaP: Zn or GaP: N. It can be understood that the material of the epitaxial layer 104 may also be other materials such as metal or alloy, as long as the material is grown by the above-mentioned growth methods such as MBE, CBE, MOVPE, etc., that is, the preparation method of the epitaxial layer 104 is The temperature of the substrate 1 provided with the carbon nanotube layer 102 and the buffer layer 1041 is maintained at 1 〇〇〇 ° c to 1100 ° C, and the ammonia gas and the carrier gas are continuously supplied while introducing trimethyl gallium or three Ethyl gallium grows a high quality outer layer 104 at elevated temperatures. Specifically, the epitax 100112849 Form No. A0101 Page 16 / Total 41 page 1002021407-0 201239949 The preparation method of the layer 104 includes the following steps [0043] S141: epitaxial growth along substantially perpendicular to the buffer layer 1 〇41 Complex epitaxial crystal; surface nucleus [0044] S142: the plurality of epitaxial grains are epitaxially grown along a direction substantially parallel to the surface of 1041 - a continuous gradual retardation layer, epitaxial thin layer; [0045] The epitaxial film is epitaxially grown along a direction substantially perpendicular to the broad surface to form an epitaxial layer 1〇4. Buffer layer 1 [ [0046] Ο In step S141, since the carbon nanotube layer 1〇2 is disposed on the surface of the '1041, the epitaxial grains are only grown from the buffer layer and the punch layer 41. That is, the epitaxial grains come out from the opening Q of the carbon nanotube layer 102. 〇5 growth [0047]

In step S142, after the epitaxial grains are grown from the carbon nanotube layer 1〇2 from the opening D of the substrate, substantially along the surface of the carbon nanotube layer 102 surrounding the surface of the buffer layer 1041. The carbon tube side is outwardly grown by % ^, and the iron is gradually integrated into one body, so that the carbon nanotube layer is 1 〇 2 half & _ _ semi-enclosed as the finger, due to the existence of the carbon nanotubes, The surface of the pad 104 forms a plurality of grooves 103, the carbon nanotube layer 1 is disposed in the groove 103, and the groove 103 and the buffer layer 1〇41 wrap the carbon nanotube layer 102 As a result, the carbon nanotubes in the nanotube breaking layer 1〇2 are in contact with the surface of the groove 103. The plurality of grooves ι 3 form a "patterned" structure on the surface of the epitaxial layer 104, and the patterned surface of the outer layer 104 is substantially identical to the pattern in the patterned carbon nanotube layer. 1125 [0048] 100112849 In step S15, the method for removing the substrate 100 may be a laser irradiation method, single number A0101, page 1/3, total 41 pages, 1〇〇2〇214〇7, 〇201239949, corrosion method or temperature difference self-peeling law. The removal method can be selected according to the material of the substrate 100 and the epitaxial layer 104. [0049] In this embodiment, the method for removing the substrate 100 is a laser irradiation method. Specifically, the removing method includes the following steps: [0050] S151, polishing and cleaning the surface of the substrate 100 where the epitaxial layer 1〇4 is not grown; [0051] S152, placing the surface-cleaned substrate 100 on a substrate (not shown), and scanning and irradiating the substrate 100 and the epitaxial layer 104 by using a misalignment; [0052] S153, immersing the substrate 1 after laser irradiation into a solution to remove the substrate 100, The substrate 1 having the microstructure is formed. [0053] In step S151, the polishing method may be a mechanical polishing method or a chemical polishing method to flatten the surface of the substrate 100 to reduce scattering of laser light in subsequent laser irradiation. The cleaning may be performed by rinsing the surface of the substrate 100 with hydrochloric acid, sulfuric acid or the like to remove metal impurities, oil stains and the like on the surface. [0054] In step S152, the laser is incident from the polished surface of the substrate 1 , and the incident direction is substantially perpendicular to the polished surface of the substrate 1 , ie, substantially perpendicular to the substrate 100 and the epitaxial layer. 1〇4 interface. The wavelength of the laser is not limited and may be selected according to the materials of the buffer layer 1041 and the substrate 1〇〇. Specifically, the energy of the laser is less than the band gap energy of the substrate 1 ,, and is greater than the band gap energy of the buffer layer 1041 so that the laser can pass through the substrate 1 〇〇 to reach the buffer layer 1041 at the buffer layer 1 〇 41 and the substrate Laser peeling was performed at the interface of 1 inch. The buffer layer 1〇41 at the interface strongly absorbs the laser, so that the temperature of the buffer layer 1〇41 at the interface is rapidly increased and decomposed 100112849. Form No. A0101 Page 18/41 Page 1002021407-0 201239949 Ο [ 0055] [0057] [0057]. In this embodiment, the epitaxial layer 104 is GaN, and the band gap energy is 3·3 ev; the substrate 100 is sapphire, and the band gap energy is 9. 9 ev; the laser is a laser wavelength emitted by the KrF laser device. It is 248nm, its energy is 5ev, the pulse width is 2〇~40ns, and the energy density is 4〇〇~6〇〇mJ/cm2. The spot shape is square, its focusing size is 〇. 5mmx 〇· 5mm; scanning position is from 5毫米/斯。 The starting step of the substrate 1 开始, scanning step length of 0. 5mm / s. The GaN buffer layer 1041 begins to decompose into 〇3 and \ during scanning. It can be understood that the pulse width, the energy density, the spot shape, the focus size and the scanning step length can be adjusted according to actual needs; the laser of the corresponding wavelength can be selected according to the buffer layer 1041 to have a strong absorption of the laser of a specific wavelength. The GaN buffer layer 1041 has a strong absorption effect on the laser of the above wavelength, and therefore, the temperature of the buffer layer 1041 rapidly rises and decomposes; and the epitaxial layer 104 has weak or no absorption of the laser light of the above wavelength. Therefore, the epitaxial layer 104 is not destroyed by the laser. It can be understood that lasers of different wavelengths can be selected for different buffer layers 1041 to make the buffer layer 1041 have a strong absorption effect on the laser. The laser irradiation process is carried out in a vacuum environment or a protective gas atmosphere to prevent the carbon nanotubes from being destroyed by oxidation during the laser irradiation. The protective gas may be an inert gas such as nitrogen, helium or argon. In step S153, the substrate 100 and the epitaxial layer 1〇4 after laser irradiation may be immersed in an acidic solution to remove Ga after decomposition of GaN. Thereby, the substrate 100 and the epitaxial layer 104 are peeled off to form the micro-structured substrate iO. The solution may be a solvent capable of dissolving Ga such as hydrochloric acid, sulfuric acid or nitric acid. Due to the presence of the buffer layer 1041, on the one hand, the buffer layer 1 〇 41 is set to 100112849. Form No. A0101, page 19 / 41 pages 1002021407-0 201239949 is disposed between the carbon nanotube layer 102 and the substrate 100, The carbon nanotubes in the carbon nanotube layer 102 are isolated from the substrate 100. Therefore, during the process of peeling off the substrate 100, the carbon nanotubes are not directly adsorbed on the substrate 100 and are peeled off from the epitaxial layer 104; In one aspect, during the laser irradiation of the buffer layer 1041, after the buffer layer 1041 is thermally decomposed and dissolved by the solution, the carbon nanotube layer 102 is detached from the buffer layer 1041, so that the carbon nanotubes are retained. In the groove 103. Further, during the thermal decomposition of the buffer layer 1041, the gas generated by the decomposition of the buffer layer 1041 is thermally expanded, and the carbon nanotube layer 102 is pushed away from the buffer layer 1041 and the substrate 100, thereby making the carbon nanotube layer 102 is more easily separated from the buffer layer 1041. [0058] Due to the presence of the carbon nanotube layer 102, the contact area between the epitaxial layer 104 and the buffer layer 1041 is reduced, thereby reducing the epitaxial layer 104 during the growth process. The stress between the layers 1041. Therefore, in the process of removing the substrate 100 by laser irradiation, the peeling of the buffer layer 1041 and the substrate 100 is made easier, and the damage to the epitaxial layer 104 is also reduced. As shown in FIG. 7 and FIG. 8 , the present invention further provides a micro-structured substrate 10 prepared by the first embodiment. The micro-structured substrate 10 includes an epitaxial layer 104, and the epitaxial layer 104 has A patterned surface, a carbon nanotube layer 102 is disposed on the patterned surface of the epitaxial layer 104. The carbon nanotube layer 102 is embedded in the surface of the epitaxial layer 104. [0060] Specifically, the surface patterned by the epitaxial layer 104 has a plurality of grooves 103, and the carbon nanotubes in the carbon nanotube layer 102 are disposed in the grooves 103 of the epitaxial layer 104, thereby A carbon nanotube layer 102 is embedded in the surface of the epitaxial layer 104. The carbon nanotubes in the carbon nanotube layer 102 are partially exposed to the surface by the surface of the groove 103 by 100112849 Form No. A0101 Page 20 of 41 1002021407-0 201239949. The micro-structured substrate 10 refers to the microstructure of the epitaxial layer 104 having a plurality of grooves 103 formed on the surface, and the mixed structure is difficult to grow in the layer 1 () 4, and the epitaxial layer 1 〇 4 is from the nano layer. The opening in the carbon tube layer 102 is grown, and then formed by lateral epitaxial growth around the carbon nanotube. After the substrate 1 is peeled off, a plurality of grooves 3 are formed on the surface of the epitaxial layer 104. Therefore, the microstructures described in this embodiment are the grooves 103 of the epitaxial layer 104. [0061] Ο

G The carbon nanotube layer 102 is a self-supporting structure. The carbon nanotube layer comprises a carbon nanotube membrane or a nanocarbon pipeline. In this embodiment, the carbon nanotube layer 102 is a single-layer carbon nanotube film, and the carbon nanotube film includes a plurality of carbon nanotubes, and the axial direction of the plurality of carbon nanotubes is preferentially oriented in the same direction. The adjacent carbon nanotubes extending in the same direction are connected end to end by van der Waals force. A micro-hole or gap is provided at a portion of the interval between adjacent carbon nanotubes perpendicular to the extending direction to constitute the opening 105. The carbon nanotube layer 1〇2 has a plurality of openings 丨〇5, and the epitaxial layer 1〇4 penetrates into the plurality of openings 105′ of the carbon nanotube layer 102, that is, the plurality of carbon nanotube layers 102 The epitaxial layer 104 is infiltrated throughout the opening 105. The opening 105 has a size of 1 〇 nanometer to 3 〇 0 μm, or 10 nm to 12 〇 micrometers, or 10 nanometers to 80 micrometers, or 1 nanometer to 10 micrometers. The smaller the size of the opening 105, the less the generation of misalignment defects during the growth of the epitaxial layer 104, to obtain a high quality epitaxial layer 104. Preferably, the opening 105 has a size of 10 nm to 10 μm. The surface of the epitaxial layer 104 has a plurality of grooves 103, and each of the grooves 103 is provided with a carbon nanotube or a plurality of carbon nanotubes. The composition of the tube bundles 'the carbon nanotubes disposed in the plurality of grooves 103 are mutually connected by van der Waals to form the carbon nanotubes 100112849 Form No. 1010101 21 tribute / Total 41 pages 1002021407-0 201239949 Layer 102. The carbon nanotubes in the carbon nanotube layer 102 are in partial contact with the inner surface of the groove 103. Because of the strong adsorption of the carbon nanotubes, the carbon nanotubes are adsorbed to the concave surface by the van der Waals force. In the slot 103. [0062] Further, the carbon nanotube layer 102 may also be a plurality of parallel and spaced carbon nanotubes. The surface of the epitaxial layer 104 has a plurality of parallel and spaced grooves 103, which are correspondingly disposed in the grooves 103 of the surface of the epitaxial layer 104. The distance between adjacent two nanocarbon lines is from 0.1 micron to 200 micron, preferably from 10 micron to 100 micron. The space between the adjacent two nanocarbon lines constitutes the opening 105 of the carbon nanotube layer 102. The smaller the size of the opening 105, the less the generation of misalignment defects during the growth of the epitaxial layer 104, to obtain a high quality epitaxial layer 104. [0063] Further, the carbon nanotube layer 102 may also be a plurality of carbon nanotubes that are interdigitated and spaced apart. Specifically, the plurality of carbon nanotubes are respectively disposed in parallel with the second direction along the first direction. One direction is intersected with the second direction. The surface of the epitaxial layer 104 has a plurality of intersecting grooves 103, and the nanocarbon pipelines are disposed correspondingly in the grooves 103 to form a lattice structure. Preferably, the two nanocarbon lines intersecting each other are perpendicular to each other. It can be understood that the nano carbon pipeline can also be arranged in any intersecting manner to form a grid structure, and only the carbon nanotube layer 102 is formed into a plurality of openings 105, so that the epitaxial layer 104 can penetrate and extend out of the opening 105. A plurality of grooves 103 are formed corresponding to the mesh structure to form a patterned surface. [0064] The micro-structured substrate provided by this embodiment can directly have a micro-structure 100112849 because the carbon nanotube layer is directly exposed to the surface of the epitaxial layer. Form No. A0101 Page 22 / Total 41 Page 1002021407-0 The large-area electrode of the substrate of 201239949 can improve the electric field distribution and current direction in the substrate with different microstructures, and improve the working efficiency of the substrate with micro-structure. [0065] The third embodiment of the present invention provides The method for preparing the substrate 1(4) comprises the following steps: just S21, providing a substrate 1〇〇, and the substrate 1〇〇 has an epitaxial growth surface 10 supporting the growth of the epitaxial layer 104}: [0067] S22, at the substrate 1GG Epitaxial growth surface 1Q1 growth-buffer layer 1〇41; 〇[0068] S23, a carbon nanotube layer 102 is laid on the surface of the buffer layer 1041 away from the substrate 1〇〇; [0069] S24, in the setting The epitaxial layer 104 is grown on the surface of the buffer layer 1〇41 having the carbon nanotube layer 1〇2; [0070] S25, the substrate is immersed in an etching solution, and the substrate is peeled off to obtain the substrate 10 having the microstructure. Q [0071] This hair The manufacturing method of the micro-structured substrate 10 of the second embodiment is substantially the same as that of the first embodiment, except that the material of the substrate 100 in the embodiment is Sic, which is grown on the epitaxial growth surface 101. The buffer layer 1041 is A1N or TiN, the epitaxial layer 104 is GaN, and the removal method is a rot method. [0072] Specifically, in step S24, the substrate 100 on which the epitaxial layer 1〇4 is grown is immersed into In the corresponding etching solution, the buffer layer 1041 is dissolved in the solution, thereby achieving separation of the substrate 100. The solution may be selected according to the material of the buffer layer 1041 and the epitaxial layer 1〇4, that is, the solution is soluble 100112849 Form No. A0101 Page 23 / Total 41 Page 1002021407-0 201239949 The buffer layer 1041 is not dissolved and the epitaxial layer i〇4 is not dissolved. The solution may be a NaOH solution, a KOH solution, a NH4〇H solution or the like, this embodiment _, The solution is a K0H solution. The quality concentration of the K0H solution may be 3〇%~5〇%, and the immersion time is 2 minutes~1〇 minutes, so that the K0H solution is immersed in the groove 103 of the epitaxial layer 104, and gradually erodes away. A1N buffer layer makes The Sic substrate is detached. Since the carbon nanotubes in the carbon nanotube layer 1〇2 are in contact with the groove 1〇3, the carbon nanotubes have a strong adsorption effect, so during the corrosion of the buffer layer 1041, The a1N is gradually dissolved in the K〇H solution to be detached from the surface of the carbon nanotube, so that the carbon nanotube is adsorbed in the groove 1〇3, and the substrate 1 having the microstructure is obtained. It is to be understood that the material of the buffer layer 1041 and the solution is not limited to the above, as long as the solution is capable of dissolving the buffer layer 1041 and not dissolving the epitaxial layer 1〇4. When the buffer layer is TiN, the solution may be nitric acid. [0073] Further, in the etching method, the substrate 1〇〇 may be directly dissolved and removed, so that the buffer layer 1〇41 and the substrate 1〇〇 can be simultaneously dissolved during the dissolution process, so that the nanometer is made. The carbon tube layer 1〇2 is exposed to the surface of the epitaxial layer 1〇4. It will be appreciated that if the substrate 100 is directly dissolved and removed, the step of growth buffering can also be omitted. [0074] In the etching method, due to the presence of the carbon nanotube layer 1〇2, there are a plurality of grooves or gaps between the carbon nanotube layer 102 and the buffer layer 1〇41, so that the corresponding solution can be made uniform. Dispersing into the buffer layer 1〇41 dissolves the buffer layer 1〇41 to achieve rapid peeling, and it is possible to better maintain the smoothness and smoothness of the peeling surface of the micro-structured substrate. [0075] A third embodiment of the present invention provides a method for fabricating a substrate 1 having a microstructure, and specifically includes the following steps: 100112849 Form No. A0101 Page 24 / Total 41 Page 1002021407-0 201239949 [0076] [0078] [0080] θ [0081] ❹ 100112849 S31, a substrate 100 is provided, and the substrate 100 has an epitaxial growth surface 101 supporting the growth of the epitaxial layer 104; S32, a buffer is grown on the epitaxial growth surface 101 of the substrate 100. a layer 1041; S33, a carbon nanotube layer 102 is laid on the surface of the buffer layer 1041 away from the substrate 100; S34, an epitaxial layer is grown on the surface of the buffer layer 1041 provided with the carbon nanotube layer 102; S35 The substrate 100 on which the epitaxial layer 104 is grown is cooled, and the substrate 100 is peeled off to obtain the substrate 10 having the microstructure. The method of fabricating the microstructured substrate 10 of the third embodiment of the present invention is substantially the same as the method of fabricating the semiconductor layer of the first embodiment, and the difference is that, in step S35, the stripping method is a temperature difference separation method. The temperature difference separation method is to rapidly reduce the temperature of the south temperature substrate 100 to below 200 ° C in the time of 2 min to 20 min after the completion of the growth of the GaN at the south temperature, using the epitaxial layer 104 and the substrate 100. The stress due to the difference in thermal expansion coefficient separates the two. It can be understood that in the method, the epitaxial layer 104 and the substrate 100 can be heated by applying an electric current to the carbon nanotube layer 102, and then cooled to achieve peeling. In the process of peeling off the substrate 100, the carbon nanotubes in the carbon nanotube layer 102 are adsorbed in the grooves 103 without falling off. This is because on the one hand, the carbon nanotube layer 102 is a unitary structure, and there is contact with the groove 103; on the other hand, the carbon nanotubes in the carbon nanotube layer 102 are embedded in the epitaxial layer 104. In the middle, the groove 103 partially encloses the carbon nanotube; thirdly, the substrate 100 can be peeled off in a direction parallel to the patterned surface of the epitaxial layer 104, so that the form number A0101 page 25/41 page 1002021407- 0 201239949 The carbon nanotube remains in the groove 103. Further, after the epitaxial layer 104 is separated from the substrate 100, a step of continuously growing the epitaxial layer laterally on the surface of the epitaxial layer 104 may be included. The step of further growing the epitaxial layer can reduce cracking on the epitaxial layer 104 during the separation of the substrate 100. [0082] As shown in FIG. 9, a fourth embodiment of the present invention provides a method for fabricating a substrate 20 having a microstructure, which mainly includes the following steps: [0083] S41, a substrate 100 is provided, and the substrate 100 has a supporting epitaxial structure. The epitaxial growth surface 101 of the layer 104 is grown; [0084] S42, a buffer layer 1041 is grown on the epitaxial growth surface 101 of the substrate 100; [0085] S43, the surface of the buffer layer 1041 away from the substrate 100 is laid flat. a carbon nanotube layer 202; [0086] S44, an epitaxial layer 104 is grown on the surface of the buffer layer 1041 provided with the carbon nanotube layer 102; [0087] S45, a further layer is disposed on the surface of the epitaxial layer 104 away from the substrate 100. a carbon nanotube layer 202; [0088] S46, further growing an epitaxial layer 2 0 4 on the surface of the epitaxial layer 104 away from the substrate 100; [0089] S47, peeling the substrate 100 to obtain the micro-structured The substrate 20 is prepared in the same manner as the first embodiment, and the difference is that the epitaxial layer 104 is further laid away from the surface of the buffer layer 1041. One carbon nanotube layer 202 100112849 form Step S45 of No. A0101, page 26 of 41, 1002021407-0 201239949, and step S46 of further growing an epitaxial layer 2〇4. The carbon nanotube layer 2〇2 is disposed in contact with the epitaxial layer 1〇4, and the epitaxial layer 204 is grown around the carbon nanotubes in the carbon nanotube layer 2〇2, and the nano-stone is discolored. The tube layer 202 is sandwiched between the epitaxial layer 1〇4 and the epitaxial layer 204, and the carbon nanotubes are embedded in the epitaxial layer 204. Due to the presence of the carbon nanotubes, the epitaxial layer 2〇4 forms a plurality of recesses 1〇3' near the surface of the epitaxial layer 104. The carbon nanotube layer 202 is disposed in the recesses 1〇3. The plurality of recesses 103 form a "patterned" structure on the surface of the epitaxial layer 2?4, and the patterned surface of the epitaxial layer 204 is substantially the same as the pattern in the patterned carbon nanotube layer 2?. The carbon nanotube layer 202 and the epitaxial layer 204 are substantially the same as the structure of the carbon nanotube layer 1〇2 and the epitaxial layer 104, respectively, and the material of the epitaxial layer 204 may be the same as or different from the epitaxial layer 1〇4. . It can be understood that the carbon nanotube layer can be further disposed on the surface of the epitaxial layer 2〇4, and the epitaxial layer can be further grown to form a composite structure having a plurality of epitaxial layers and a plurality of carbon nanotube layers. The materials of the plurality of epitaxial layers may be the same or different, and the plurality of carbon nanotube layers may serve as different electrodes, so that the micro-structured substrate can be conveniently applied to different electronic devices. [0091] The method for preparing a microstructured substrate provided by the present invention has the following beneficial effects. First, the carbon nanotube layer is a self-supporting structure, and thus can be directly disposed on the buffer layer by a laying method. The surface can form a uniform carbon nanotube layer on the surface of the buffer layer without complicated steps, and the method is simple and controllable, which is advantageous for mass production; secondly, the carbon nanotube layer is a patterned structure. The thickness and opening size can reach the nanometer level, and the epitaxial grains formed when the epitaxial layer is grown have 1002021407-0 100112849. Form No. A0101 Page 27 / Total 41 Page 201239949 Smaller size, which is beneficial to reduce misalignment defects Produced to obtain a high-quality epitaxial layer; again, due to the presence of the carbon nanotube layer, the contact area between the grown epitaxial layer and the buffer layer is reduced, and the epitaxial layer and the buffer layer during growth are reduced. The stress between them can further grow the thicker epitaxial layer and further improve the quality of the epitaxial layer; at the same time, since the carbon nanotube layer has a plurality of openings, The contact area between the epitaxial layer and the buffer layer is small, and therefore, in the process of peeling off the substrate, peeling of the substrate is made easier, and damage to the epitaxial layer is also reduced. [0092] 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 in light of the spirit of the invention are intended to be included within the scope of the following claims. BRIEF DESCRIPTION OF THE DRAWINGS [0093] FIG. 1 is a process flow diagram of a method of fabricating a substrate having a microstructure in accordance with a first embodiment of the present invention. 2 is a scanning electron microscope photograph of a carbon nanotube film used in the first embodiment of the present invention. 3 is a schematic structural view of a carbon nanotube segment in the carbon nanotube film of FIG. 2. 4 is a scanning electron micrograph of a carbon nanotube film of a plurality of cross-settings used in the present invention. 5 is a scanning electron micrograph of a non-twisted nanocarbon pipeline used in the present invention 100112849 Form No. A0101 Page 28/41 Page 1002021407-0 201239949 [0098] FIG. 6 is a twisted nanometer used in the present invention. Scanning electron micrograph of the carbon pipeline. 7 is a schematic view of a substrate having a microstructure in accordance with a first embodiment of the present invention. 8 is a schematic cross-sectional view of the substrate having the microstructure shown in FIG. 7 taken along line Μ-Μ. 9 is a process flow diagram of a method for fabricating a substrate having a microstructure according to a fourth embodiment of the present invention. 〇[0102] [Description of main component symbols] Substrate with microstructure: 10,20 [0103] Substrate: 100 S [0104] Epitaxial growth surface: 101 [0105] Carbon nanotube layer: 102, 202 [0106] Concave Slot: 103 [0107] Epitaxial layer: 104, 204 W [0108] Opening: 105 [0109] Buffer layer: 1041 [0110] Carbon nanotube segment: 143 [0111] Carbon nanotube: 145 100112849 Form number A0101 29 pages / total 41 pages 1002021407-0

Claims (1)

201239949 VII. Patent application scope: 1 . A method for preparing a substrate having a microstructure, which comprises the following steps: providing a sapphire substrate having an epitaxial growth surface; growing on the epitaxial growth surface of the substrate a low temperature GaN buffer layer; a carbon nanotube layer disposed on the surface of the buffer layer; a GaN epitaxial layer grown on the surface of the buffer layer; and removing the substrate. 2. The method for preparing a microstructured substrate according to claim 1, wherein the substrate is removed by scanning the substrate with a laser in a vacuum environment or a protective gas atmosphere. The method for preparing a micro-structured substrate according to claim 2, wherein the laser wavelength is 248 nm, the pulse width is 20 to 40 ns, and the energy density is 400 to 600 mJ/cm 2 . The spot shape is a square, and the focus size is 0. 5mmx0. 5mm, and the scanning step is 〇·5mm/s. 4. A method of fabricating a microstructured substrate, comprising the steps of: providing a substrate having an epitaxial growth surface; growing a buffer layer on an epitaxial growth surface of the substrate; and disposing a surface on the buffer layer a carbon nanotube layer; an epitaxial layer is grown on the surface of the buffer layer provided with the carbon nanotube layer; and the substrate is removed. 5. The method of preparing a microstructured substrate according to claim 4, wherein the nanocarbon layer is a continuous self-supporting structure. 6. The method of preparing a microstructured substrate according to claim 4, wherein the carbon nanotube layer is disposed in contact with the buffer layer. 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 The carbon nanotube layer has a plurality of openings from which the epitaxial layer is epitaxially grown. The method of preparing a microstructured substrate according to claim 7, wherein the buffer layer is exposed from an opening of the carbon nanotube layer, and the epitaxial layer is grown from the exposed portion of the buffer layer. The method for preparing a microstructured substrate according to the fourth aspect of the invention, wherein the epitaxial layer forms a plurality of grooves around the carbon nanotube layer, the grooves to the carbon nanotubes The carbon nanotubes in the layer are half surrounded. The method for preparing a microstructured substrate according to the fourth aspect of the invention, wherein the method for growing the epitaxial layer comprises molecular beam epitaxy, chemical beam epitaxy, reduced pressure epitaxy, low temperature epitaxy, selective epitaxy One or more of a method, a liquid phase deposition epitaxy method, a metal organic vapor phase epitaxy method, an ultra-vacuum chemical vapor deposition method, a hydride vapor phase epitaxy method, and a metal organic chemical vapor deposition method. The method for preparing a substrate having a microstructure as described in claim 4, wherein the method for removing the substrate comprises a laser irradiation method, an etching method, and a temperature difference separation method. The method for preparing a microstructured substrate according to claim 4, further comprising: before the substrate is removed, a carbon nanotube layer disposed on the surface of the epitaxial layer away from the substrate; and the epitaxial layer The step of further growing the epitaxial layer away from the surface of the substrate. A micro-structured substrate comprising a semiconductor epitaxial layer and a carbon nanotube layer, wherein a surface of the semiconductor epitaxial layer has a plurality of grooves to form a patterned surface, and the carbon nanotube layer is disposed on the semiconductor The patterned surface of the epitaxial layer is embedded in the semiconductor epitaxial layer. The micro-structured substrate according to claim 13, wherein the carbon nanotubes in the carbon nanotube layer are disposed on the substrate of the micro-structure of the carbon nanotubes of claim 13; The groove of the patterned surface. 15. The microstructured substrate of claim 14, wherein the carbon nanotube layer is partially exposed to the patterned surface. The micro-structured substrate according to claim 13, wherein each of the grooves is provided with a carbon nanotube or a carbon nanotube bundle composed of a plurality of carbon nanotubes, and is disposed in a plurality of concave The carbon nanotubes in the tank are connected to each other by a van der Waals force to form the carbon nanotube layer. The microstructural substrate of claim 13, wherein the carbon nanotube layer has a plurality of openings, each of which is infiltrated with a semiconductor epitaxial layer. 18. The microstructured substrate of claim 13, wherein the carbon nanotubes in the carbon nanotube layer are in contact with the inner surface of the groove, and the carbon nanotubes are Adsorbed in the groove under the action of wattage. 100112849 Form No. A0101 Page 32 of 41 1002021407-0