Preparation method of multilayer micro-nano material

Abstract

This invention discloses a method for preparing multilayer micro / nanomaterials, comprising the following steps: preparing a first growth layer on a patterned thin film structure having a filled region and a first region outside the filled region to obtain a first multilayer micro / nanostructure, wherein the first upper surface of the first growth layer in the filled region is not higher than the upper surface of the first region; preparing an auxiliary mask layer on the first multilayer micro / nanostructure, wherein the material of the auxiliary mask layer is different from that of the first growth layer; performing mask etching using a planar removal etching method until the first growth layer on the upper surface of the first region is completely removed; removing the residual auxiliary mask layer in a manner that does not damage the residual first growth layer to obtain the finished multilayer micro / nanostructure, thereby protecting the first growth layer in the filled region through the residual auxiliary mask layer; and the difficulty of mask removal is not significantly related to the thickness of the patterned mask layer, the filled region, and the first growth layer.

Description

Technical Field

[0001] This invention relates to the field of micro-nano device technology, and more specifically to a method for preparing multilayer micro-nano materials. Background Technology

[0002] As micro- and nano-devices develop towards higher integration and multifunctionality, their structures are gradually evolving from planar two-dimensional to three-dimensional stacked structures. Multilayer micro / nano material filling technology aims to solve the core fabrication challenge of accurately, non-destructively, and conformally filling various heterogeneous materials into deep trenches or pores at the nanoscale. It provides crucial process support for overcoming the limitations of traditional planar photolithography, achieving device miniaturization, and realizing new physical effects, and has significant application prospects in fields such as three-dimensional chip packaging, multilayer optical filters, metamaterials, and energy storage devices.

[0003] Currently, multilayer micro / nano material filling typically requires first forming trenches or pores on the material surface to achieve precise, non-destructive, and conformal filling of the multilayer material. The conventional process involves retaining the mask after material patterning and etching, depositing the filler material, and then physically or chemically peeling off the mask to form the desired pattern. However, this process is limited by factors such as mask thickness, filling depth, and filler material thickness. Especially when the pattern size is small and dense, or when the material etching and filler deposition thickness are large, mask peeling is often difficult. In such cases, re-etching is usually required before filler material deposition to form a thicker mask, thereby improving the peeling success rate. However, this method is complex, has a narrow process window, is difficult to adjust flexibly according to actual conditions, and is prone to problems such as pattern displacement and surface morphology degradation. Furthermore, methods such as chemical mechanical polishing (CMP) planarization to remove the mask and material outside the filling area require specific equipment under strict conditions, resulting in high costs, long process cycles, poor process compatibility, and the planarization process may damage the surface of sensitive materials. Summary of the Invention

[0004] To address at least one of the aforementioned problems, according to one aspect of the present invention, a method for preparing multilayer micro / nanomaterials is provided.

[0005] The method for preparing this multilayer micro / nanomaterial includes the following steps: S20: A first growth layer is prepared on a patterned thin film structure to obtain a first multilayer micro / nano structure. The patterned thin film structure has a filled region and a first region outside the filled region. The first upper surface of the first growth layer in the filled region is not higher than the upper surface of the first region. S30: An auxiliary mask layer is prepared on the first multilayer micro-nano structure to obtain a second multilayer micro-nano structure. The material of the auxiliary mask layer is different from the material of the first growth layer. S40: The mask etching process is performed by planar removal etching until the first growth layer on the upper surface of the first region is completely removed to obtain the third multilayer micro-nano structure. The part of the first growth layer in the third multilayer micro-nano structure that is in the filling region is the residual first growth layer, and the part of the auxiliary mask layer in the third multilayer micro-nano structure that is in the filling region is the residual auxiliary mask layer. S50: Remove the residual auxiliary mask layer without damaging the residual first growth layer to obtain the multilayer micro / nano structure product.

[0006] This invention sets the first upper surface of the first growth layer in the filled region to be no higher than the upper surface of the first region outside the filled region in the patterned thin film structure. This allows a residual auxiliary mask layer to remain on the first upper surface of the first growth layer in the filled region during planar removal etching until the first growth layer on the upper surface of the first region is completely removed. This residual auxiliary mask layer protects the first growth layer in the filled region. Furthermore, the removal difficulty of the patterned mask layer and the residual auxiliary mask layer is far lower than that of the first growth layer, and the removal difficulty is not significantly related to the thickness of the patterned mask layer, the filled region, and the first growth layer. Moreover, it eliminates the need for the complex and unstable process of re-etching a thicker mask before the first growth layer is prepared to improve the lift-off success rate, and also eliminates the need for costly, time-consuming, and incompatible methods such as CMP to remove the mask and materials outside the filled region. This application proposes a method for preparing multilayer micro / nano materials. This method is applicable to scenarios involving patterning and dense filling of micro / nano materials, and can solve the problems of difficult peeling after material deposition, poor morphology, and complex pattern filling processes. Moreover, the technical solution of this application can be realized through conventional micro / nano processes, with low equipment requirements. The process is universal, simple, compatible, and inexpensive, which is of great significance in promoting the application of micro / nano device fabrication technology from the laboratory to practical use.

[0007] In some embodiments, in step S20, the pattern in the patterned thin film structure is at the micrometer and / or nanometer scale. When used on thin film structures with micrometer or nanometer scale patterns, the method of the present invention can achieve rapid and efficient mask removal without significantly increasing cost or reducing efficiency, even if the patterned mask layer is thick, the filling region is deep, or the first growth layer is thick.

[0008] In some embodiments, in step S30, the thickness of the auxiliary mask layer within the filled region is greater than its thickness outside the filled region. Therefore, when the first growth layer on the upper surface of the first region is completely removed in step S40 using a planar removal etching method, the auxiliary mask layer still remains in the filled region to provide physical protection for the first growth layer within the filled region.

[0009] In some embodiments, the upper surface of the auxiliary mask layer is planar in step S30. Therefore, when the first growth layer on the upper surface of the first region is completely removed in step S40 using a planar removal etching method, the auxiliary mask layer still remains in the filled region to provide physical protection for the first growth layer in the filled region.

[0010] In some embodiments, in step S20, the first growth layer can be prepared by at least one of the following methods: evaporation, sputtering, electroplating, and vapor deposition. This allows the first growth layer to be uniformly grown onto the surface of the patterned thin film structure.

[0011] In some embodiments, in step S30, the auxiliary mask layer can be prepared by at least one of spin coating, thermal deposition, or selective growth. Thus, the auxiliary mask layer, due to its fluidity, can have a thickness greater in the filled area than outside the filled area, or its final upper surface can be planar.

[0012] In some embodiments, in step S20, the patterned thin film structure is patterned on the patterned thin film structure by providing a patterned mask layer on the bottom material layer.

[0013] In some embodiments, the material of the auxiliary mask layer is at least one of photoresist, electron adhesive, electron beam resist, spin-coated glass, spin-coated polymer, and low-melting-point metal. Thus, an auxiliary mask layer with a thickness greater in the filled area than outside the filled area, or an auxiliary mask layer with a planar upper surface, can be obtained by spin coating, selective growth, or thermal deposition.

[0014] In some implementations, the bottom material layer is a patterned bottom material layer, and the patterned thin film structure is not removed before the first growth layer is fabricated. The patterned mask layer can increase the height difference between the inside and outside of the filled area, enlarge the process window, increase the etching time range, and increase the process tolerance.

[0015] In some embodiments, the bottom material layer is a non-patterned bottom material layer, and the patterned thin film structure is not removed before the first growth layer is fabricated. Thus, the first growth layer can be given a structure with a specific pattern using the patterned mask layer.

[0016] In some implementations, the material of the first growth layer is different from the material of the patterned mask layer. Therefore, by selecting a suitable method for removing the patterned mask layer, the surface of the first growth layer can be removed without damaging it.

[0017] In some embodiments, the patterned mask layer is made of a different material than the surface material of the underlying material layer without being removed before fabricating the first growth layer. Therefore, by selecting a suitable method for removing the patterned mask layer, the surface of the underlying material layer can be removed without damaging it.

[0018] In some embodiments, without removing the patterned mask layer before fabricating the first growth layer, the removal of the residual auxiliary mask layer in step S50 also avoids damaging the surface of the underlying material layer. Therefore, by selecting a suitable method for removing the residual auxiliary mask layer, it is possible to remove it without damaging the surface of the underlying material layer.

[0019] In some embodiments, the material of the patterned mask layer is photoresist, electron beam resist, porous material film, nanoimprint stencil, metal, non-metal, metal compound, non-metal compound, electron paste, SiO2, and SiN. x At least one of them.

[0020] In some embodiments, the bottom material layer is a patterned bottom material layer, and the patterned thin film structure has its patterned mask layer removed before the first growth layer is fabricated. Since the patterned mask layer is difficult to remove after the first growth layer is fabricated, removing the patterned mask layer before fabricating the first growth layer can reduce the difficulty of patterned mask layer removal.

[0021] In some embodiments, the first growth layer grows in both the filled region and the first region. Therefore, the first growth layer can be prepared using conventional growth processes, avoiding increased production costs.

[0022] In some embodiments, the patterned mask layer is removed before the first growth layer is fabricated, and the removal of the patterned mask layer does not damage the surface of the underlying material layer. Therefore, the surface of the underlying material layer can be kept undamaged during the removal of the patterned mask layer.

[0023] In some embodiments, based on removing the patterned mask layer before preparing the first growth layer, in step S50, the method of removing the residual auxiliary mask layer without damaging the residual first growth layer and the patterned bottom material layer is at least one of dry etching, wet etching, plasma treatment, adhesion, and high-temperature decomposition.

[0024] In some implementations, planar removal etching can be achieved through dry etching or grinding and polishing.

[0025] In some embodiments, the material of the first growth layer is at least one of a metal, a metal compound, a nonmetal, a nonmetal compound, and a polymer. Attached Figure Description

[0026] Figure 1 This is a schematic diagram of a patterned thin film structure according to the first embodiment of the method for preparing multilayer micro / nano materials of the present invention. Figure 2 This is a schematic diagram of the first multilayer micro / nano structure of the multilayer micro / nano material preparation method according to the first embodiment of the present invention. Figure 3 This is a schematic diagram of the second multilayer micro / nano structure of the multilayer micro / nano material preparation method according to an embodiment of the present invention; Figure 4 This is a schematic diagram of the third multilayer micro-nano structure in the multilayer micro-nano material preparation method of the first embodiment of the present invention. Figure 5 The multilayer micro-nano structure product of the multilayer micro-nano material preparation method of the first embodiment of the present invention; Figure 6 This is a schematic diagram of a patterned thin film structure according to the second embodiment of the method for preparing multilayer micro / nano materials of the present invention. Figure 7 This is a schematic diagram of the first multilayer micro-nano structure of the multilayer micro-nano material preparation method according to the second embodiment of the present invention. Figure 8 This is a schematic diagram of the second multilayer micro-nano structure of the multilayer micro-nano material preparation method according to the second embodiment of the present invention. Figure 9 This is a schematic diagram of the third multilayer micro-nano structure in the second embodiment of the preparation method of multilayer micro-nano materials of the present invention. Figure 10 The multilayer micro-nano structure product of the multilayer micro-nano material preparation method according to the second embodiment of the present invention; Figure 11 This is a schematic diagram of a patterned thin film structure according to the third embodiment of the preparation method of multilayer micro / nano materials of the present invention. Figure 12 This is a schematic diagram of the first multilayer micro-nano structure of the multilayer micro-nano material preparation method according to the third embodiment of the present invention. Figure 13 This is a schematic diagram of the second multilayer micro-nano structure of the multilayer micro-nano material preparation method according to the third embodiment of the present invention. Figure 14 This is a schematic diagram of the third multilayer micro-nano structure in the third embodiment of the preparation method of multilayer micro-nano materials of the present invention. Figure 15 for Figure 1 A schematic diagram of the graphic thin film structure from another perspective; Figure 16This is a schematic diagram of a patterned thin film structure according to another embodiment of the present invention; Figure 17 This is a schematic diagram of a patterned thin film structure according to another embodiment of the present invention; Reference numerals: 21 / 21` / 21``, patterned thin film structure; 210 / 210` / 210``, bottom material layer; 211 / 211` / 211``, first material layer; 212 / 212` / 212``, second material layer; 213 / 213`, patterned mask layer; 2131 / 2131`, second upper surface; 214 / 214` / 214``, filled region; 22 / 22` / 22``, first growth layer; 221 / 221` / 221``, first growth sublayer; 222 / 222` / 222` `、Second growth sublayer; 2221 / 2221` / 2221``、First upper surface; 222a / 222a` / 222a``、Residual first growth layer; 22a / 22a` / 22a``、First multilayer micro / nano structure; 23 / 23` / 23``、Auxiliary mask layer; 231 / 231` / 231``、Residual auxiliary mask layer; 231a / 231a` / 231a``、Third multilayer micro / nano structure; 23a / 23a` / 23a``、Second multilayer micro / nano structure; 24 / 24`、Finished multilayer micro / nano structure. Detailed Implementation

[0027] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other.

[0028] It should also be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising" or "including" include not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Unless otherwise specified, an element defined by the phrase "comprising..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element. The terminology used herein is generally that commonly used by those skilled in the art; in case of any discrepancy with commonly used terminology, the terminology used herein shall prevail.

[0029] In this invention, the term "micro / nanomaterials" refers to materials with thickness and / or pattern size in the micrometer and / or nanometer range.

[0030] Furthermore, for ease of description, spatial relative terms such as “below,” “under,” “lower,” “above,” and “upper” may be used herein to describe the relationship between one element or component and another (or other elements or components) as shown in the figure. In addition to the orientations shown in the figure, spatial relative terms are intended to include different orientations of the device during use or operation. The device may be oriented in other ways (rotated 90 degrees or in other orientations), and the spatial relative descriptors used herein can be interpreted accordingly.

[0031] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0032] According to the present invention, a method for preparing multilayer micro / nanomaterials is provided.

[0033] The method for preparing this multilayer micro / nanomaterial includes the following steps: S20: A first growth layer is prepared on a patterned thin film structure to obtain a first multilayer micro / nano structure. The patterned thin film structure has a filled region and a first region outside the filled region. The first upper surface of the first growth layer in the filled region is not higher than the upper surface of the first region. S30: An auxiliary mask layer is prepared on the first multilayer micro-nano structure to obtain a second multilayer micro-nano structure. The material of the auxiliary mask layer is different from the material of the first growth layer. S40: The mask etching process is performed by planar removal etching until the first growth layer on the upper surface of the first region is completely removed to obtain the third multilayer micro-nano structure. The part of the first growth layer in the third multilayer micro-nano structure that is in the filling region is the residual first growth layer, and the part of the auxiliary mask layer in the third multilayer micro-nano structure that is in the filling region is the residual auxiliary mask layer. S50: Remove the residual auxiliary mask layer without damaging the residual first growth layer to obtain the multilayer micro / nano structure product.

[0034] If a stripping process of the patterned mask layer is used after step S20, it is possible to obtain a multilayer micro / nano structure. However, this process is limited by factors such as mask thickness, filling depth, and filling material thickness. Especially when the pattern size is small (sub-micron) and dense, or when the material etching and filling material deposition thickness are large, the mask is often difficult to strip. For example, when the pattern is at the micro / nano level and there is at least one of the following conditions: small patterned mask layer thickness, large filling depth, and large first growth layer thickness, the patterned mask layer may be difficult to strip. Moreover, since the patterned mask layer is covered by the first growth layer, conventional stripping processes are extremely difficult to remove the first growth layer and patterned mask layer outside the filling area. The solution is difficult to penetrate and dissolve. Generally, the thickness of the patterned mask layer needs to be controlled to be more than three times the thickness of the first growth layer to achieve easier stripping of the first growth layer and patterned mask layer outside the filling area.

[0035] This invention, by setting the first upper surface of the first growth layer in the filled region to be no higher than the upper surface of the first region outside the filled region in the patterned thin film structure, allows a residual auxiliary mask layer to remain on the first upper surface of the first growth layer in the filled region during planar removal etching until the first growth layer on the upper surface of the first region is completely removed. This residual auxiliary mask layer protects the first growth layer in the filled region. Furthermore, the removal difficulty of the patterned mask layer and the residual auxiliary mask layer is far lower than that of the first growth layer, and the removal difficulty is not significantly related to the thickness of the patterned mask layer, the filled region, and the first growth layer. Moreover, it eliminates the need for the complex and unstable process of re-etching a thicker mask before the first growth layer is prepared to improve the lift-off success rate, and also eliminates the need for costly, time-consuming, and incompatible methods such as CMP to remove the mask and materials outside the filled region. This application proposes a method for preparing multilayer micro / nano materials. This method is applicable to scenarios involving patterning and dense filling of micro / nano materials, and can solve the problems of difficult peeling after material deposition, poor morphology, and complex pattern filling processes. Moreover, the technical solution of this application can be realized through conventional micro / nano processes, with low equipment requirements. The process is universal, simple, compatible, and inexpensive, which is of great significance in promoting the application of micro / nano device fabrication technology from the laboratory to practical use.

[0036] In some embodiments, the patterned thin film structure can be an epitaxial structure or a film of other materials (e.g., metal film, oxide film, nitride film, etc.) grown on the surface of the epitaxial structure.

[0037] In some embodiments, in step S20, the pattern in the patterned thin film structure is micrometer-scale and / or nanometer-scale. When used on thin film structures with micrometer-scale or nanometer-scale patterns, the method of the present invention can achieve rapid and efficient mask removal without significantly increasing cost or reducing efficiency, even if the patterned mask layer is thick, the filling region is deep, or the first growth layer is thick.

[0038] In some embodiments, the material of the first growth layer is at least one of a metal, a metal compound, a nonmetal, a nonmetal compound, and a polymer.

[0039] In some embodiments, in step S20, the first growth layer can be prepared by at least one of the following methods: vapor deposition, sputtering, electroplating, and vapor deposition.

[0040] In some embodiments, in step S20, the patterned thin film structure is patterned on the patterned thin film structure by providing a patterned mask layer on the bottom material layer.

[0041] In some embodiments, the first growth layer is grown in both the filled region and the first region. Therefore, the first growth layer can be prepared using conventional growth processes, thus avoiding increased production costs.

[0042] In some embodiments, in step S20, the patterning employs photolithography or electron beam exposure techniques commonly used in the prior art.

[0043] In some embodiments, such as Figure 1 As shown, the patterned thin film structure includes a first material layer, a second material layer epitaxially grown on the first material layer, and a patterned mask layer on the surface of the second material layer, wherein the pattern is formed on the second material layer. In some embodiments, the first material layer is made of sapphire, and / or the second material layer is made of GaN.

[0044] In some preferred embodiments, the material of the patterned mask layer is photoresist, electron beam resist, porous material film, nanoimprint stencil, metal, non-metal, metal compound, non-metal compound, electron adhesive, SiO2, and SiN. x At least one of them.

[0045] In some preferred embodiments, the material of the patterned mask layer is different from the surface material of the underlying material layer, so that by selecting an appropriate removal method for the patterned mask layer, the surface of the underlying material layer can be removed without damaging it.

[0046] In some embodiments, such as Figure 15 As shown, in step S20, the patterned shape is an array of distributed circles to form a filled area in the pattern. In other embodiments, such as Figure 16 As shown, in step S20, the graphic shape is an array of rectangles to form a filled area in the graphic.

[0047] In some embodiments, in step S30, the thickness of the auxiliary mask layer within the filled region is greater than its thickness outside the filled region, so that when the first growth layer on the upper surface of the first region is completely removed by a planar removal etching method in step S40, the auxiliary mask layer still remains in the filled region, providing physical protection for the first growth layer in the filled region. And / or in some embodiments, in step S30, the upper surface of the auxiliary mask layer is planar, so that when the first growth layer on the upper surface of the first region is completely removed by a planar removal etching method in step S40, the auxiliary mask layer still remains in the filled region, providing physical protection for the first growth layer in the filled region.

[0048] In some embodiments, in step S30, the auxiliary mask layer can be prepared by at least one of spin coating, thermal deposition, and selective growth.

[0049] In some embodiments, the material of the auxiliary mask layer is at least one of photoresist, electron adhesive, electron beam resist, spin-coated glass, spin-coated polymer, and low-melting-point metal.

[0050] In some embodiments, planar removal etching can be achieved through dry etching or grinding and polishing.

[0051] In some embodiments, the dry etching technique may employ any of the existing techniques such as ICP (Inductively Coupled Plasma), IBE (Ion Beam Etching), and RIE (Reactive Ion Etching).

[0052] Figures 1 to 5 The structure of a product prepared by the multilayer micro / nanomaterial preparation method according to the first embodiment of the present invention is shown by way of example.

[0053] In some embodiments, the bottom material layer is a non-graphical bottom material layer (such as...). Figure 1 As shown), the patterned thin film structure does not remove the patterned mask layer before fabricating the first growth layer (as shown). Figure 2 As shown), the first growth layer has a specific pattern structure by using a patterned mask layer.

[0054] In some preferred embodiments, the material of the first growth layer is different from the material of the patterned mask layer, so that by selecting an appropriate removal method for the patterned mask layer, the surface of the first growth layer can be removed without damaging it.

[0055] In some embodiments, an auxiliary mask layer is fabricated on the first multilayer micro / nanostructure to obtain a second multilayer micro / nanostructure, such as... Figure 3 As shown.

[0056] In some embodiments, a planar removal etching method is used for mask etching until the first growth layer on the upper surface of the first region is completely removed, resulting in a third multilayer micro / nano structure. Figure 4 As shown.

[0057] In some embodiments, the residual auxiliary mask layer is removed without damaging the residual first growth layer to obtain a multilayer micro / nano structure product, such as... Figure 5 As shown.

[0058] In some embodiments, without removing the patterned mask layer before preparing the first growth layer, the method of removing the residual auxiliary mask layer in step S50 does not damage the surface of the bottom material layer. By selecting an appropriate method for removing the residual auxiliary mask layer, the surface of the bottom material layer can be removed without damaging it.

[0059] In some embodiments, in step S50, the method of removing the residual auxiliary mask layer without damaging the residual first growth layer is at least one of dry etching, wet etching, plasma treatment, adhesion, and high-temperature decomposition.

[0060] Figures 6 to 10 The structure of a product prepared by the multilayer micro / nanomaterial preparation method according to the second embodiment of the present invention is shown by way of example.

[0061] The main difference between the second embodiment of the multilayer micro / nanomaterial preparation method and the first embodiment is that the bottom material layer is a patterned bottom material layer (e.g., Figure 6 As shown), the patterned thin film structure does not remove the patterned mask layer before fabricating the first growth layer (as shown). Figure 7 As shown, by using a patterned mask layer to increase the height difference between the inside and outside of the filling area, the process window is enlarged, the etching time range is increased, and the process tolerance is increased.

[0062] In some preferred embodiments, such as Figures 6 to 9 As shown, when the patterned thin film structure includes a first material layer, a second material layer epitaxially grown on the first material layer, and a patterned mask layer on the surface of the second material layer, the first material layer is patterned, while the second material layer is not patterned.

[0063] In some embodiments, an auxiliary mask layer is fabricated on the first multilayer micro / nanostructure to obtain a second multilayer micro / nanostructure, such as... Figure 8 As shown.

[0064] In some embodiments, a planar removal etching method is used for mask etching until the first growth layer on the upper surface of the first region is completely removed, resulting in a third multilayer micro / nano structure. Figure 9 As shown.

[0065] In some embodiments, the residual auxiliary mask layer is removed without damaging the residual first growth layer to obtain a multilayer micro / nano structure product, such as... Figure 10 As shown.

[0066] Figures 11 to 14 The structure of a product prepared by the multilayer micro / nanomaterial preparation method according to the third embodiment of the present invention is shown by way of example.

[0067] The main difference between the third embodiment of the multilayer micro / nanomaterial preparation method and the second embodiment is that the bottom material layer is a patterned bottom material layer, resulting in a patterned thin film structure as shown in the figure. Figure 11 As shown, the patterned thin film structure is obtained by removing the patterned mask layer before fabricating the first growth layer, resulting in the first multilayer micro / nano structure. Figure 12 As shown.

[0068] In some embodiments, the patterned mask layer is removed before the first growth layer is prepared, and the removal of the patterned mask layer does not damage the surface of the bottom material layer, so that the surface of the bottom material layer can be guaranteed to remain undamaged when the patterned mask layer is removed.

[0069] In some embodiments, an auxiliary mask layer is fabricated on the first multilayer micro / nanostructure to obtain a second multilayer micro / nanostructure, such as... Figure 13 As shown.

[0070] In some embodiments, a planar removal etching method is used for mask etching until the first growth layer on the upper surface of the first region is completely removed, resulting in a third multilayer micro / nano structure. Figure 14 As shown.

[0071] In some embodiments, the residual auxiliary mask layer can be removed without damaging the residual first growth layer to obtain a multilayer micro / nano structure product. (See reference for further details.) Figure 10 As shown.

[0072] In some embodiments, based on removing the patterned mask layer before preparing the first growth layer, in step S50, the method of removing the residual auxiliary mask layer without damaging the residual first growth layer and the patterned bottom material layer is at least one of dry etching, wet etching, plasma treatment, adhesion, and high-temperature decomposition.

[0073] Figure 17 The structure of a product prepared by the multilayer micro / nanomaterial preparation method according to the fourth embodiment of the present invention is shown by way of example.

[0074] The main difference between the fourth embodiment of the multilayer micro / nanomaterial preparation method and the second embodiment is that the patterned thin film structure only includes a first material layer and a patterned mask layer on the surface of the second material layer. The first material layer is patterned (e.g., ...). Figure 17 (As shown).

[0075] This application's technical solution is applicable to multilayer micro / nanomaterial filling at the wafer level of various sizes, and is not limited by pattern size, pattern distribution, material type, or material thickness relationship (such as the ratio of photoresist to deposited film thickness). It causes no damage to the materials (bottom and filling material), and has significant advantages, especially for filling multilayer materials within holes with pattern size and spacing below the hundred nanometer scale. It offers a large process window, good repeatability, stability and controllability, low cost, simple process, and good compatibility with micro / nano device fabrication processes. Using this method, excellent multilayer micro / nanomaterial filling effects can be achieved through conventional micro / nano processes. This application's technical solution can also be applied to other scenarios requiring material patterning through mask peeling, unaffected by the relationship between mask thickness and deposited material thickness; the patterning accuracy can be improved by reducing the mask thickness.

[0076] The following specific embodiments illustrate the preparation method of multilayer micro / nano materials of this application.

[0077] The experimental methods described in the examples are all conventional methods; the reagents, materials and equipment involved are all commercially available.

[0078] Example 1 This embodiment describes a method for preparing multilayer micro / nanomaterials, and the preparation steps include: First, a second material layer 212 is epitaxially grown on a first material layer 211 using chemical vapor deposition (CVD). The first and second material layers 211 together constitute a non-patterned bottom material layer 210. Then, a patterned mask layer 213 is formed on the surface of the second material layer 212 using electron beam lithography (EBRT) to form a filling region 214 on the patterned mask layer 213. The pattern size is on the micrometer scale. The material of the first material layer 211 is a sapphire substrate, the material of the second material layer 212 is GaN, and the material of the patterned mask layer 213 is photoresist. The first material layer 211, the second material layer 212, and the patterned mask layer 213 together constitute a patterned thin film structure 21 (e.g., ...). Figure 1 (As shown).

[0079] The second step involves depositing a first growth layer 22 on the patterned thin film structure 21 using vapor deposition. The material of the first growth layer is Ni / TiN / SiO2, resulting in... Figure 2 The first multilayer micro / nano structure 22a shown; the first growth layer 22 includes a first growth sublayer 221 deposited on the second upper surface 2131 of the patterned mask layer 21 and a second growth sublayer 222 deposited in the filling region 214, wherein the first upper surface 2221 of the second growth sublayer 222 is not higher than the second upper surface 2131 of the patterned mask layer 21.

[0080] The third step involves spin-coating an auxiliary mask layer 23 onto the first multilayer micro / nano structure 22a. The auxiliary mask layer 23 is made of photoresist, resulting in the following... Figure 3 The second multilayer micro / nano structure 23a is shown; the thickness of the auxiliary mask layer 23 within the filled region 214 is greater than its thickness outside the filled region.

[0081] Fourthly, the second multilayer micro / nano structure 23a is subjected to planar removal etching using ICP technology to completely remove the first growth layer 22 (i.e., the first growth sublayer 221) on the second upper surface 2131 of the patterned mask layer 213. The remaining portion of the first growth layer 22 in the filled region 214 is the residual first growth layer 222a, resulting in the following... Figure 4 The third multilayer micro / nano structure 231a is shown.

[0082] Fifth step: Remove the residual auxiliary mask layer 231 in the patterned mask layer 213 and the filled area 214 by wet etching to obtain the following... Figure 5 The multilayer micro / nano structure product 24 is shown.

[0083] Example 2 This embodiment describes a method for preparing multilayer micro / nanomaterials, and the preparation steps include: The first step involves epitaxially growing a second material layer on a first material layer using chemical vapor deposition (CVD). Then, a patterned mask layer is formed on the surface of the second material layer using electron beam lithography (EBRT). The pattern size is on the micrometer scale. The first material layer is a sapphire substrate, the second material layer is GaN, and the patterned mask layer is made of photoresist. The resulting structural reference... Figure 1 As shown.

[0084] In the second step, using the patterned mask layer 213' as a protective layer, the second material layer 212' is etched using a dry etching method, so that the second material layer 212' and the patterned mask layer 213' form a filling region 214'. The first material layer 211' and the second material layer 212' together constitute the patterned bottom material layer 210', resulting in a patterned thin film structure 21' as shown in the figure. Figure 6 As shown.

[0085] The third step involves depositing a first growth layer 22' on the patterned thin film structure 21' using vapor deposition. The material of the first growth layer 22' is Ni / TiN / SiO2, resulting in the following... Figure 7 The first multilayer micro / nano structure 22a' shown; the first growth layer 22' includes a first growth sublayer 221' deposited on the second upper surface 2131' of the patterned mask layer 213' and a second growth sublayer 222' deposited in the filling region 214', wherein the first upper surface 2221' of the second growth sublayer 222' is not higher than the second upper surface 2131' of the patterned mask layer 213'.

[0086] Fourth step: An auxiliary mask layer 23' is deposited on the first multilayer micro / nano structure 22a' using spin coating. The material of the auxiliary mask layer 23' is photoresist, resulting in the following... Figure 8 The second multilayer micro / nano structure 23a' shown has an auxiliary mask layer 23' with a thickness within the filling region 214' that is greater than its thickness outside the filling region 214'.

[0087] Fifth, the second multilayer micro / nano structure 23a' is subjected to planar removal etching using ICP technology to completely remove the first growth layer 22' (i.e., the first growth sublayer 221') on the second upper surface 2131' of the patterned mask layer 213'. The remaining portion of the first growth layer 22' in the filled region 214' is the residual first growth layer 222a', resulting in the following... Figure 9 The third multilayer micro / nano structure 231a' is shown.

[0088] Step 6: Remove the residual auxiliary mask layer 231' in the patterned mask layer 213' and the filled area 214' using wet etching to obtain the following... Figure 10 The multilayer micro / nano structure product 24' is shown.

[0089] Example 3 This embodiment describes a method for preparing multilayer micro / nanomaterials, and the preparation steps include: The first step involves epitaxially growing a second material layer 212'' on a first material layer 211'' using molecular beam epitaxy. Then, a patterned mask layer is formed on the surface of the second material layer 212'' using photolithography. The pattern size is on the nanometer scale. The material of the first material layer 212'' is GaN, the material of the second material layer 212'' is TiO2, and the material of the patterned mask layer is SiO2. The resulting structural reference... Figure 1 As shown.

[0090] The second step involves using a patterned mask layer as a protective layer and employing dry etching to etch the second material layer 212'', causing the second material layer 212'' to form the filling region 214''. The first material layer 211'' and the second material layer 212'' together constitute the bottom material layer 210', resulting in a structural reference. Figure 6 As shown.

[0091] The third step involves removing the patterned mask layer using wet etching to obtain the patterned thin film structure 21``. Figure 11 As shown.

[0092] The fourth step involves depositing a first growth layer 22'' on the patterned thin film structure 21'' using sputtering. The material of the first growth layer 22'' is Al, resulting in the following... Figure 12 The first multilayer micro / nano structure 22a`` is shown; the first growth layer 22`` includes a first growth sublayer 221`` deposited on the upper surface of the second material layer 212`` and a second growth sublayer 222`` deposited in the filling region 214``, wherein the first upper surface 2221`` of the second growth sublayer 222`` is not higher than the upper surface of the second material layer 212``.

[0093] Fifth step: An auxiliary mask layer 23'' is deposited on the first multilayer micro / nano structure 22a'' using a thermal deposition method. The material of the auxiliary mask layer 23'' is photoresist, resulting in... Figure 13 The second multilayer micro / nano structure 23a`` is shown; the upper surface of the auxiliary mask layer 23a`` is planar.

[0094] Step 6: Using IBE technology, the second multilayer micro / nano structure 23a'' is subjected to planar removal etching to completely remove the first growth layer 22'' (i.e., the first growth sublayer 221'') on the upper surface of the second material layer 212''. The portion of the first growth layer 22'' remaining in the filling region 214'' is the residual first growth layer 222a'', and the portion of the auxiliary mask layer 23'' remaining in the filling region 214'' is the residual auxiliary mask layer 231'', resulting in the following... Figure 14The third multilayer micro / nano structure 231a`` is shown.

[0095] Step 7: Remove the residual auxiliary mask layer 231'' in the filled area by wet etching. The resulting multilayer micro / nano structure can be referenced. Figure 10 As shown.

[0096] Example 4 This embodiment describes a method for preparing multilayer micro / nanomaterials, and the preparation steps include: The first step involves using chemical vapor deposition (CVD) to form a patterned mask layer on the first material layer via electron beam lithography. The pattern size is on the micrometer scale. The first material layer (212'') is made of GaN, and the patterned mask layer is made of SiN. x .

[0097] The second step involves using a patterned mask layer as a protective layer and employing dry etching to etch the first material layer, forming the filling region. The resulting patterned thin film structure is shown below. Figure 17 As shown.

[0098] The third step involves depositing a first growth layer on the patterned thin film structure using electroplating. The material of the first growth layer is Al, resulting in a first multilayer micro / nano structure. The first growth layer includes a first growth sublayer deposited on the second upper surface of the patterned mask layer and a second growth sublayer deposited in the filling region. The first upper surface of the second growth sublayer is not higher than the second upper surface of the patterned mask layer.

[0099] The fourth step involves depositing an auxiliary mask layer on the first multilayer micro / nano structure using selective area growth. The auxiliary mask layer is made of electronic adhesive, resulting in the second multilayer micro / nano structure. The thickness of the auxiliary mask layer within the filled region is greater than its thickness outside the filled region.

[0100] The fifth step involves performing planar removal etching on the second multilayer micro / nano structure using RIE technology. This completely removes the first growth layer (first growth sublayer) on the second upper surface of the patterned mask layer. The remaining portion of the first growth layer in the filled area is the residual first growth layer, resulting in the third multilayer micro / nano structure.

[0101] The sixth step involves removing the patterned mask layer and residual auxiliary mask layer in the filled area using wet etching to obtain the finished multilayer micro / nano structure.

[0102] The above descriptions are merely some embodiments of the present invention. Those skilled in the art can make various modifications and improvements without departing from the inventive concept of the present invention, and these all fall within the scope of protection of the present invention.

Claims

1. A method for preparing multilayer micro / nano materials, characterized in that, Includes the following steps: S20: A first growth layer is prepared on a patterned thin film structure to obtain a first multilayer micro / nano structure. The patterned thin film structure has a filled region and a first region outside the filled region. The first upper surface of the first growth layer in the filled region is not higher than the upper surface of the first region. S30: An auxiliary mask layer is prepared on the first multilayer micro-nano structure to obtain a second multilayer micro-nano structure, wherein the material of the auxiliary mask layer is different from the material of the first growth layer. S40: The mask etching process is performed by planar removal etching until the first growth layer on the upper surface of the first region is completely removed to obtain the third multilayer micro-nano structure. The part of the first growth layer in the third multilayer micro-nano structure that is in the filling region is the residual first growth layer, and the part of the auxiliary mask layer in the third multilayer micro-nano structure that is in the filling region is the residual auxiliary mask layer. S50: Remove the residual auxiliary mask layer without damaging the residual first growth layer to obtain the multilayer micro / nano structure product.

2. The method for preparing multilayer micro / nanomaterials according to claim 1, characterized in that, In step S20, the patterns in the patterned thin film structure are micrometer-scale and / or nanometer-scale; and / or In step S30, the thickness of the auxiliary mask layer within the filling area is greater than the thickness outside the filling area, or the upper surface of the auxiliary mask layer is planar.

3. The method for preparing multilayer micro / nanomaterials according to claim 2, characterized in that, In step S20, the first growth layer can be prepared by at least one of the following methods: evaporation, sputtering, electroplating, and vapor deposition; and / or In step S30, the auxiliary mask layer can be prepared by at least one of spin coating, thermal deposition, and selective growth.

4. The method for preparing multilayer micro / nanomaterials according to claim 2, characterized in that, In step S20, the patterned thin film structure is patterned on the patterned thin film structure by setting a patterned mask layer on the bottom material layer; and / or The auxiliary mask layer is made of at least one of photoresist, electron adhesive, electron beam resist, spin-coated glass, spin-coated polymer, and low-melting-point metal.

5. The method for preparing multilayer micro / nano materials according to claim 4, characterized in that, The bottom material layer is a patterned bottom material layer, and the patterned thin film structure does not remove the patterned mask layer before preparing the first growth layer.

6. The method for preparing multilayer micro / nano materials according to claim 5, characterized in that, The material of the first growth layer is different from the material of the patterned mask layer; and / or The material of the patterned mask layer is different from the surface material of the bottom material layer.

7. The method for preparing multilayer micro / nanomaterials according to claim 6, characterized in that, In step S50, the removal of the residual auxiliary mask layer does not damage the surface of the underlying material layer; and / or The patterned mask layer is made of photoresist, electron beam resist, porous material film, nanoimprint adhesive, metal, non-metal, metal compound, non-metal compound, electron adhesive, SiO2, and SiN. x At least one of them.

8. The method for preparing multilayer micro / nanomaterials according to claim 4, characterized in that, The bottom material layer is a patterned bottom material layer, and the patterned thin film structure has its patterned mask layer removed before the first growth layer is fabricated; and / or The first growth layer grows in both the filled region and the first region.

9. The method for preparing multilayer micro / nano materials according to claim 8, characterized in that, The method of removing the patterned mask layer does not damage the surface of the underlying material layer; and / or In step S50, the method for removing the residual auxiliary mask layer without damaging the residual first growth layer and the patterned bottom material layer is at least one of dry etching, wet etching, plasma treatment, adhesion, and high-temperature decomposition.

10. The method for preparing multilayer micro / nanomaterials according to any one of claims 1 to 9, characterized in that, The planar removal etching method can be achieved through dry etching or grinding and polishing; and / or The material of the first growth layer is at least one of metal, metal compound, nonmetal, nonmetal compound and polymer.

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