Imprinting apparatus, holding portion, transfer method, method of manufacturing electrical-electronic application product, method of manufacturing display, and holding method for holding in imprinting apparatus

Abstract

Provided is a press device, a holding portion for a press device, a transfer method using the press device, a manufacturing method of an electrical-electronic application product using the transfer method, and a manufacturing method of a display, which inhibit adhesion of a microstructure to a surface other than the holding portion of the press device, and in the case where the microstructure is accidentally adhered to the surface, inhibit the microstructure from falling off from the press device. A press device 100 for transferring a microstructure 200 includes a base portion 1 formed on a substrate 10, a holding portion 2 formed on the base portion 1 and having a holding surface 21 for holding the microstructure 200, and an adhesion-inhibiting portion 3 formed around the holding portion 2 on the base portion 1 and having a plurality of convex portions 4 having an adhesion-inhibiting surface 41 having a height lower than the holding surface 21, the adhesion-inhibiting portion 3 being formed to have a cohesive force with which the microstructure 200 does not fall off under a force lower than the weight of the microstructure 200 in the case where the microstructure 200 is adhered to the adhesion-inhibiting portion 3.

Description

Technical Field

[0001] The present invention relates to an imprinting apparatus for transferring a small structure such as a semiconductor element formed or disposed on a substrate to another substrate, a holding part for the imprinting apparatus, a transfer method using the imprinting apparatus, a method for manufacturing an electrical-electronic application product using the transfer method, a method for manufacturing a display, and a holding method for holding the imprinting apparatus. Background Technology

[0002] In recent years, with the miniaturization of semiconductor components, microstructure transfer technology using imprinting devices has attracted attention as an assembly method for electrical and electronic application products that use semiconductor components. In particular, the development of technologies for manufacturing LED displays for signage, television (TV), medical applications, automotive, tablet, smartphone, smartwatch, and augmented reality / virtual reality (AR / VR) applications has become active. This technology allows for the transfer of one or more, or even tens of thousands, of miniature light-emitting diodes (LEDs) (with short sides of 100 μm or more to several tens of thousands) at once.

[0003] The imprinting apparatus, for example, has a convex holding portion 2 made of polydimethylsiloxane (PDMS) rubber, which allows microstructures to attach to the holding portion 2 and be transferred from the supply substrate to the receiving substrate. However, due to various conditions such as pressure conditions, substrate thickness, dot height, imprinting apparatus area, and unfavorable height position of the micro-LEDs, microstructures may sometimes accidentally attach to portions other than the holding portion 2 of the imprinting apparatus. Furthermore, there are cases where micro-LEDs or other foreign matter present as contaminants in the process environment, such as cleaning solutions, may adhere during the imprinting process. Especially when micro-LEDs are attached, the contact area with the imprinting apparatus is relatively large, making removal very difficult by cleaning. If such an imprinting apparatus with attached micro-LEDs is used for pick-up again, the attached micro-LEDs may come into contact with new micro-LEDs and be damaged. Additionally, when using an imprinting apparatus with attached foreign matter, allowing foreign matter to adhere to the micro-LEDs at the transfer source or the micro-LEDs or substrate at the transfer destination may lead to defects. Therefore, as... Figure 1 As shown, it is also considered to prevent accidental attachment of micro-LEDs by providing small protrusions 49 in the portion other than the retaining part 2 (for example, Patent Document 1).

[0004] Existing technical documents

[0005] Patent documents

[0006] Patent Document 1: Japanese Patent No. 6453437 Summary of the Invention

[0007] The problem that the invention aims to solve

[0008] However, even if the surface other than the holding part 2 of the printing apparatus is made rough, it is difficult to completely prevent microstructures from accidentally adhering to the parts other than the holding part 2 of the printing apparatus. On the other hand, if a protrusion 49 is provided on the surface other than the holding part 2 of the printing apparatus, the adhering microstructures will fall off from the printing apparatus before the cleaning process of the printing apparatus, resulting in contamination of the transport path, etc.

[0009] Therefore, the object of the present invention is to provide an embossing device, an embossing device, a embossing device holding part, an embossing device, a transfer method using the embossing device, a method for manufacturing an electrical-electronic application product using the transfer method, a method for manufacturing a display, and a method for holding the embossing device in such cases as microstructures accidentally attach to the surface, which can prevent the microstructures from detaching from the embossing device.

[0010] Technical means to solve the problem

[0011] (X1) To achieve the aforementioned objective, the imprinting apparatus of the present invention is an imprinting apparatus for transferring microstructures, characterized in that it comprises: a base portion formed on a substrate; a holding portion formed on the base portion having a holding surface for holding the microstructure; and an adhesion suppression portion formed on the base portion, having a plurality of protrusions around the holding portion, the protrusions having an adhesion suppression surface with a height lower than the holding surface, wherein when the microstructure is attached to the adhesion suppression portion, the adhesion suppression portion is formed to have an adhesive force that prevents the microstructure from falling off under a force less than the weight of the microstructure.

[0012] (X2) In addition, the imprinting apparatus of the present invention is an imprinting apparatus for transferring microstructures, characterized in that it includes: a base portion formed on a substrate; a holding portion formed on the base portion having a holding surface for holding the microstructure; and an adhesion suppression portion formed on the base portion having a plurality of protrusions around the holding portion, the protrusions having an adhesion suppression surface with a height lower than the holding surface, the area B of the adhesion suppression surface being more than 1 / 100 times the area A of the holding surface.

[0013] (X3) In this case, the area B of the adhesion inhibition surface should preferably be less than 1 / 2 of the area A of the retention surface.

[0014] (X4) Furthermore, the imprinting apparatus of the present invention is an imprinting apparatus for transferring microstructures, characterized in that it includes: a base portion formed on a substrate; a holding portion formed on the base portion having a holding surface for holding the microstructure; and an adhesion suppression portion formed on the base portion having a plurality of protrusions around the holding portion, the protrusions having an adhesion suppression surface with a height lower than the holding surface, the adhesion suppression portion having a shape such that, when a plane with the same shape as the holding surface contacts the adhesion suppression portion at any position, the total contact area T between the plane and the adhesion suppression surface is more than 1 / 100 times the area A of the holding surface.

[0015] (X5) In this case, the adhesion suppression part should preferably be in the shape of a plane with the same shape as the holding surface that is in contact with the adhesion suppression part at any position, such that the total contact area T between the plane and the adhesion suppression surface is less than 1 / 2 times the area A of the holding surface.

[0016] (X6) Furthermore, the imprinting apparatus of the present invention is an imprinting apparatus for transferring microstructures, characterized in that it includes: a base portion formed on a substrate; a holding portion formed on the base portion having a holding surface for holding the microstructure; and an adhesion suppression portion formed on the base portion having a plurality of protrusions around the holding portion, the protrusions having an adhesion suppression surface with a height lower than the holding surface, the adhesion suppression portion having a shape such that, when the microstructure is in contact with the adhesion suppression surface at any position, the total contact area T' with the adhesion suppression surface is at least 1 / 100 times the area A' of the microstructure.

[0017] (X7) Here, the adhesion suppression part should preferably be in the shape of such that, when the microstructure and the adhesion suppression part are in contact at any position, the total contact area T' with the adhesion suppression surface is at most 1 / 2 times or less the area A' of the microstructure.

[0018] (X8) Furthermore, the imprinting apparatus of the present invention is an imprinting apparatus for transferring microstructures, characterized in that it includes: a base portion formed on a substrate; a holding portion formed on the base portion having a holding surface for holding the microstructure; and an adhesion suppression portion formed on the base portion, having a plurality of protrusions around the holding portion, the protrusions having an adhesion suppression surface with a height lower than the holding surface, and having a shape in which the product of the adhesion force of the material constituting the adhesion suppression surface and the area of ​​the adhesion suppression surface is more than 1 / 100 times the product of the adhesion force of the material constituting the adhesion holding portion and the area of ​​the adhesion holding portion.

[0019] (X9) Here, the product of the adhesive force of the material constituting the adhesion-inhibiting surface and the area of ​​the adhesion-inhibiting surface should preferably be less than 1 / 2 times the product of the adhesive force of the material constituting the adhesion-retaining part and the area of ​​the adhesion-retaining part.

[0020] (X10) In addition, the imprinting apparatus of the present invention is an imprinting apparatus for transferring microstructures, characterized in that it includes: a base portion formed on a substrate; and a holding portion formed on the base portion, having a holding surface for holding the microstructure, and having a plurality of protrusions on the side surface connecting the base portion and the holding surface, the protrusions having an adhesion inhibition surface with a height lower than the holding surface.

[0021] (X11) Here, at least a portion of the retaining part is preferably cylindrical, prismatic, frustum conical, or a shape formed by beveling a portion of these.

[0022] (X12) Furthermore, the transfer method of the present invention can use the imprinting apparatus of the present invention to transfer microstructures. Additionally, the method for manufacturing an electrical-electronic application product of the present invention includes a step of transferring microstructures using the aforementioned transfer method. Furthermore, the method for manufacturing a display of the present invention includes a step of transferring microstructures using the aforementioned transfer method.

[0023] (X13) In addition, the holding part of the present invention is a component of an imprinting device for transferring microstructures. The holding part is characterized in that it includes: a holding surface for holding the microstructures and a side surface extending toward a surface opposite to the holding surface, the side surface having a plurality of protrusions, the protrusions having an adhesion inhibition surface.

[0024] (X14) Furthermore, the transfer method of the present invention is a transfer method for transferring microstructures using an imprinting apparatus, characterized by comprising: a pick-up step for holding the microstructure on a holding surface of the imprinting apparatus; and a release step for releasing the microstructure from the holding surface of the imprinting apparatus, the imprinting apparatus comprising: a base portion formed on a substrate; a holding portion formed on the base portion having a holding surface for holding the microstructure; and an adhesion suppression portion formed on the base portion having a plurality of protrusions around the holding portion, the protrusions having an adhesion suppression surface with a height lower than the holding surface, wherein when the microstructure is attached to the adhesion suppression portion, the adhesion suppression portion has an adhesive force that prevents the microstructure from detaching under a force less than the weight of the microstructure.

[0025] (X15) Here, it is preferable to have a removal process that can remove the microstructure from the adhesion inhibition surface.

[0026] (X16) Furthermore, the transfer method of the present invention is a microstructure transfer method utilizing an imprinting device that picks up a microstructure as the transfer target and microstructures other than the transfer target. The imprinting device comprises: a base portion formed on a substrate; a holding portion formed on the base portion having a holding surface for holding the microstructure; and an adhesion suppression portion formed on the base portion, having a plurality of protrusions around the holding portion, the protrusions having an adhesion suppression surface with a height lower than the holding surface. The transfer method includes: a pick-up step holding the microstructure as the transfer target in the holding portion; and a transfer step transferring the microstructure held in the holding portion, wherein during the pick-up step, microstructures other than the transfer target are held in the adhesion suppression portion, and the adhesion force of the adhesion suppression portion is controlled such that microstructures other than the transfer target held in the adhesion suppression portion continue to be held in the adhesion suppression portion during the transfer step.

[0027] (X17) Here, it is preferable to also have a removal process, which removes the microstructures other than the transfer object that continue to remain in the adhesion inhibition section, and controls the adhesion of the adhesion inhibition section or the removal force of the removal process to remove the microstructures other than the transfer object through the removal process.

[0028] (X18) Furthermore, the method for manufacturing an electrical-electronic application product of the present invention includes a step of transferring a microstructure using the transfer method of the present invention. Additionally, the method for manufacturing a display of the present invention includes a step of transferring a microstructure using the transfer method.

[0029] (X19) Furthermore, the holding method of the present invention is a holding method for holding a microstructure other than a pickup object in an imprinting apparatus, characterized in that the imprinting apparatus includes: a base portion formed on a substrate; a holding portion formed on the base portion having a holding surface for holding the microstructure; and an adhesion suppression portion formed on the base portion having a plurality of protrusions around the holding portion, the protrusions having an adhesion suppression surface with a height lower than the holding surface, the holding method comprising: a pickup step, in which a microstructure disposed on a supply substrate as a pickup object is held on the holding surface of the imprinting apparatus; and a release step, in which the microstructure held on the holding surface as a pickup object is released from the holding surface and transferred to a receiving substrate, wherein in the pickup step, a microstructure other than a pickup object detached from the supply substrate is attached to the adhesion suppression portion, and in the state where the microstructure other than a pickup object is held in the imprinting apparatus, after the release step, in a subsequent removal step, the microstructure other than a pickup object held in the state of the imprinting apparatus is removed from the adhesion suppression surface.

[0030] The effects of the invention

[0031] The microstructure transfer embossing apparatus, the holding part for the embossing apparatus, and the transfer method using the embossing apparatus of the present invention, through the structure of the adhesion suppression part, can suppress the accidental detachment of microstructures in the event of accidental adhesion. Attached Figure Description

[0032] [ Figure 1 [ ] is a schematic cross-sectional view of an existing embossing apparatus.

[0033] [ Figure 2 [Illustration] is a schematic cross-sectional view of the embossing apparatus of the present invention.

[0034] [ Figure 3 [Illustration] is a schematic plan view of the embossing apparatus of the present invention.

[0035] [ Figure 4 [Illustration] is a schematic plan view of the embossing apparatus of the present invention.

[0036] [ Figure 5 [Illustration] is a schematic cross-sectional view showing another embossing apparatus of the present invention. Detailed Implementation

[0037] The embossing apparatus 100 of the present invention will be described below. Figure 2 , Figure 3As shown, the imprinting apparatus 100 of the present invention is used to transfer a microstructure 200 and is composed of a base portion 1, a holding portion 2, and an adhesion suppression portion 3. The base portion 1 is formed on a substrate 10, the holding portion 2 has a holding surface 21 for holding the microstructure 200, and the adhesion suppression portion 3 has a plurality of protrusions 4, the protrusions 4 having an adhesion suppression surface 41 with a height lower than the holding surface 21.

[0038] Here, the term "microstructure 200" broadly refers to objects smaller than approximately several millimeters. Specifically, the objects of microstructure 200 include integrated circuit (IC) chips, one-dimensional to three-dimensional packages assembled from ICs and large-scale integrated circuits (LSI), light-emitting diodes (LEDs) and other components including inorganic or organic semiconductors, resistors, capacitors, coils, and other electrical circuit components. Components with sizes that conventional chip bonding machines cannot handle are also included. Particularly in the case of LEDs, the demand for components with dimensions of several hundred micrometers or less is high. This invention is preferably applicable to at least a portion of structures having dimensions in the micrometer unit.

[0039] In the case of the microstructure 200 being an LED, in the case of so-called mini-LEDs with a short side of 100 μm or more to several hundred μm, LEDs with a height of 100 μm to 130 μm are currently achievable. In the case of so-called micro-LEDs with a short side of less than 100 μm or even less than 50 μm, the sapphire substrate layer is removed, resulting in a thickness of 6 μm. In this case, the in-plane deviation between the imprinting device part 13 and the surface to which the microstructure 200 is attached is preferably several times the thickness (height) of the LED.

[0040] Furthermore, tiny objects that cannot be directly grasped by vacuum suction, other than electrical-electronic circuit components, can be arbitrarily transferred and assembled using the microstructure transfer device of the present invention, thereby becoming the transfer object of the present invention, namely the microstructure 200.

[0041] The base portion 1 is formed on the substrate 10 and serves as the base for the holding portion 2 or the attachment suppressing portion 3, which will be described later. The base portion 1 can be made of any material as long as it serves as the base for the holding portion 2 or the attachment suppressing portion 3, for example, silicone rubber or PDMS (polydimethylsiloxane) rubber and other resins.

[0042] If the base portion 1 is too thick, small structures 200 other than the transfer target may easily come into contact with the base portion 1 when the holding portion 2 deforms. Furthermore, when pressure is applied, the substrate 10 and the base portion 1 tend to deform convexly to the side facing the pressure direction, and in this respect, small structures 200 other than the transfer target may also easily come into contact with the base portion 1. These factors can lead to accidental adhesion of small structures 200. Therefore, the base portion 1 should preferably be 3 times or less, more preferably 1 time or less, and even more preferably 1 / 2 time or less, the height of the holding portion 2.

[0043] The substrate 10 is the portion that serves as the base of the base portion 1. The substrate 10 can be made of any material as long as it serves as the base of the base portion 1, such as a quartz glass substrate. The quartz glass substrate is preferably synthetic quartz glass. When the size of the microstructure 200 becomes smaller and its height is less than tens of μm, the flatness of the base portion 1, which serves as the base of the holding portion 2, becomes important. This flatness is preferably within a deviation of about the height of the microstructure 200. The flatness of the quartz glass substrate, which is the substrate for the base portion 1, has a significant impact on the flatness of the base portion 1, such as a silicone-based rubber film. In the case of synthetic quartz glass, an in-plane film thickness uniformity (total thickness variation (TTV)) of about 1 μm or less can be achieved; therefore, by using synthetic quartz glass, the overall film thickness deviation of the imprinting apparatus components can be minimized. Furthermore, the advantage of using synthetic quartz glass is that thermal stability can be obtained when repeatedly performing microstructure transfer operations. That is, the synthetic quartz glass substrate has a coefficient of thermal expansion that is about 1 / 5 that of other quartz glass substrates, which can reduce thermal strain during operation. In particular, when the imprinting apparatus 100 has a holding portion 2, the positional displacement and strain (distortion) of the holding surface 21 of the holding portion 2 caused by thermal expansion and contraction can be reduced, thus enabling accurate transfer operation. Furthermore, the substrate 10 can also be integrally formed with the base portion 1, etc. For example, the substrate 10, the holding portion 2, and the adhesion suppression portion 3 can all be molded together using resin.

[0044] Furthermore, a rigid substrate is preferred. By manufacturing a rigid substrate, slack in the base portion between the holding portions during the pick-up process can be suppressed. Therefore, compared to not using a rigid substrate, the pressure applied by the imprinting apparatus during the pick-up process can be strengthened. In this invention, a rigid substrate refers to a substrate that exhibits substantially no shape change or strain during the pressure applied in the pick-up process. Specific examples include inorganic substrates such as quartz glass substrates or metal substrates. Moreover, as long as it is a rigid substrate, an organic substrate can also be used; even organic materials used for flexible substrates can be used as rigid substrates by adjusting the thickness of the substrate, etc. If it is transparent to visible light, minute structures can be easily observed via the imprinting apparatus, making alignment easier, and therefore this is preferable.

[0045] The so-called holding part 2 is a component formed on the base part 1, having a holding surface 21 for holding the microstructure 200. The number of holding parts 2 on the base part 1 can be one or more. When one is arranged on the base part 1, one of the microstructures 200 densely arranged on the supply substrate can be selectively attached to the holding surface 21 and gripped, and placed at any position on the receiving substrate. This can be used for repair by selectively transferring normal microstructures 200 to the position of defective microstructures 200. On the other hand, when multiple are arranged on the base part 1, multiple microstructures 200 corresponding to the positions of the holding parts 2 can be transferred at once.

[0046] The shape of the retaining part 2 can be any shape as long as it can hold the microstructure 200, as long as it is appropriately designed to best hold the microstructure 200 according to its shape or size. For example, at least a portion of the retaining part 2 can be a columnar shape such as a cylinder or a polygonal prism, a frustum shape such as a truncated cone or a polygonal frustum, or a shape formed by beveling a portion of these, or a shape formed by combining these.

[0047] Furthermore, if the spacing between the retaining parts 2 is large, when the retaining parts 2 deform, small structures 200 other than the transfer object may easily come into contact with the base part 1, resulting in the accidental attachment of small structures 200. Therefore, it is preferable that the retaining parts 2 are spaced apart by a distance of at least 1 / 2 times the height of the retaining parts 2, more preferably 1 times or more, and even more preferably 2 times or more.

[0048] Furthermore, if a microstructure 200 other than the object to be transferred accidentally attaches to the protrusion 4 of the attachment suppression part 3, a low height of the holding part 2 will hinder the transfer of the microstructure 200. Therefore, it is preferable that the holding part 2 be formed to be at least twice, preferably three times, or even more preferably five times the combined height of the protrusion 4 and the thickness of the microstructure 200.

[0049] The material of the retaining part 2 can be any material as long as it can retain the microstructure 200 without damaging it, such as silicone rubber or PDMS (polydimethylsiloxane) rubber and other resins. In addition, the retaining part 2 and the base part 1 can be formed of different materials or integrally formed of the same material.

[0050] The retaining surface 21 is a surface provided on the side of the retaining portion 2 facing the base portion 1, used to retain the microstructure 200 by utilizing the adhesive force of the surface. The retaining surface 21 can directly contact the microstructure 200, thereby retaining the microstructure 200. The shape of the retaining surface 21 can be any shape as long as it can retain the microstructure 200, as long as it is appropriately designed to exert the best adhesive force on the shape or size of the microstructure 200. For example, if the surface of the microstructure 200 held by the retaining surface 21 (hereinafter referred to as the held surface 201) is rectangular in plan view, it can be formed into a rectangle to accommodate it. In addition, the retaining surface 21 is not limited to a plane.

[0051] The adhesion-inhibiting portion 3 is the area surrounding the retaining portion 2 formed on the base portion 1. Furthermore, the adhesion-inhibiting portion 3 has multiple protrusions 4, each having an adhesion-inhibiting surface 41 with a height lower than the retaining surface 21. This inhibits the adhesion of microstructures 200 to the base portion 1. The adhesion-inhibiting portion 3 can be made of any material, such as silicone-based rubber or PDMS (polydimethylsiloxane) rubber. Additionally, the adhesion-inhibiting portion 3 and the base portion 1 can be formed from different materials or integrally formed from the same material.

[0052] Such an embossing apparatus can be manufactured, for example, using an embossing method as described in WO2021 / 132142. In this case, by pre-fabricating a mold with a molding pattern having a base portion, a holding portion, and an adhesion-resisting portion, it is easy to perform integral molding using the same material. Of course, other molding methods are also possible. Alternatively, the base portion, the holding portion, and the adhesion-resisting portion can be molded using different materials by dividing the molding process into multiple steps.

[0053] In addition, by using different materials on the adhesion-inhibiting surface and / or the retaining surface, the difference in adhesion between the adhesion-inhibiting surface and the retaining surface can be controlled.

[0054] The adhesion-suppressing surface 41 can be any surface, whether planar or curved, as long as it can suppress the adhesion of the microstructures 200. In addition, it can be a multifaceted structure including vertices; in this case, the apex angle of the cross-sectional shape passing through the vertex of the face perpendicular to the base surface (substrate surface) is preferably 150 degrees or more. The adhesion-suppressing surface does not need to be entirely planar or curved; it can partially consist of planar or curved surfaces, or a combination thereof. Furthermore, a space formed by a recess can be provided in the central portion, or it can have even smaller irregularities. Thus, a substantially flat surface can preferably be used as the adhesion-suppressing surface.

[0055] In order to suppress the adhesion of the microstructure 200, the adhesion suppression part 3 is formed such that the adhesion force with the microstructure 200 is weaker than that with the holding surface 21. For example, the adhesion suppression part 3 is formed by having a plurality of protrusions 4 such that the area of ​​adhesion to the microstructure 200 is smaller than that with the holding surface 21.

[0056] Regarding the shape of the adhesion suppression surface, it is preferable that the major axis diameter, when viewed from a direction perpendicular to the base surface (substrate surface), is less than twice the minor axis diameter, more preferably less than 1.5 times, and particularly preferably 1 time. By setting it within this range, it is easy to suppress the adhesion of minute structures outside the pickup object, while increasing the density of protrusions in the adhesion suppression section. Here, the minor axis diameter is defined as the minimum interval when the outline of the adhesion suppression surface is clamped by two parallel lines connected to it, and the major axis diameter is defined as the interval measured in a direction perpendicular to the minor axis diameter. By making the shape of the adhesion suppression surface circular, elliptical, polygonal, etc., it becomes easier to control the relationship between the major axis diameter and the minor axis diameter.

[0057] The shape of the connection portion (base of the protrusion) between the protrusion and the base portion constituting the adhesion suppression section is similar to the shape of the adhesion suppression surface. Preferably, the major axis diameter, when viewed from a direction perpendicular to the base portion surface (substrate surface), is 2 times or less than the minor axis diameter, more preferably 1.5 times or less, and particularly preferably 1 time. By setting it within this range, it is easy to suppress the adhesion of small structures outside the pickup object, while increasing the density of protrusions in the adhesion suppression section. Here, the minor axis diameter is defined as the minimum gap when the outline of the connection portion (base of the protrusion) between the protrusion and the base portion is clamped by two parallel lines that connect to it, and the major axis diameter is defined as the gap measured in a direction perpendicular to the minor axis diameter. By making the shape of the connection portion (base of the protrusion) between the protrusion and the base portion circular, elliptical, polygonal, or other shapes, it becomes easier to control the relationship between the major axis diameter and the minor axis diameter.

[0058] The height of the protrusion is preferably 1.5 times or less the major axis diameter of the connection portion between the protrusion and the base portion (the base of the protrusion), more preferably 1.0 times or less. In order to ensure the distance from the surface of the base portion and suppress the adhesion of small structures other than the pickup object to the base portion, it is preferably 0.3 times or more, more preferably 0.5 times or more.

[0059] On the other hand, the adhesion-inhibiting portion 3 preferably not only inhibits the adhesion of the microstructures 200, but also... Figure 3As shown, once attached to the adhesion suppression part 3, the microstructure 200 can be prevented from detaching from the imprinting device 100 and onto the transfer path due to its own weight. Therefore, when the microstructure 200 is attached to the adhesion suppression part 3, it is preferable that the adhesion suppression part 3 is formed to have an adhesive force sufficient to prevent the microstructure 200 from detaching under a force at least less than its own weight. Various design methods are considered for this adhesion suppression part 3, taking into account the microstructure 200 to be transferred. For example, it can be designed as follows.

[0060] (1) When the area A of the holding surface 21 is formed based on the weight of the microstructure 200 to be held, the area B of the adhesion suppression surface 41 can be designed as a ratio to the area A of the holding surface 21. The inventors have found that in order to stably hold the microstructure 200, the adhesion energy of the holding surface needs to be more than 100 times the adhesion energy required to hold the microstructure 200. Therefore, when the holding surface 21 and the adhesion suppression surface 41 are formed of the same material, in order to suppress the microstructure 200 that has been attached once from falling off the imprinting device 100, the area B of the adhesion suppression surface 41 should preferably be more than 1 / 100 times, more preferably more than 1 / 50 times, and even more preferably more than 1 / 30 times the area A of the holding surface 21. In addition, in order to suppress the microstructure 200 from attaching to the adhesion suppression part 3, the area B of the adhesion suppression surface 41 should preferably be less than 1 / 2 times, more preferably less than 1 / 5 times, and even more preferably less than 1 / 10 times the area A of the holding surface 21.

[0061] Furthermore, when the adhesion inhibition surface 41 is a curved surface, its area B can be estimated, for example, using the following formula based on Hertz contact theory.

[0062] B=nπ(3(1-ν2) / 4E)×(L / n)×r)2 / 3

[0063] Here,

[0064] n: The number of protrusions 4 in contact with the microstructure 200

[0065] r: radius of curvature of convex portion 4

[0066] E: Young's modulus of convex part 4

[0067] ν: Poisson's ratio of convex part 4

[0068] L: Load of microstructure 200.

[0069] (2) Furthermore, the shape of the retaining surface 21 is generally formed to match the shape of the microstructure 200 to be retained, and therefore can also be designed based on said shape. For example, such as Figure 4As shown, when an imaginary plane 300 of the same shape as the holding surface 21 and the adhesion suppression part 3 are in contact at any position, the adhesion suppression part 3 can be designed using the ratio of the total contact area T of the plane 300 and the adhesion suppression surface 41 to the area A of the holding surface 21. To suppress the detachment of the microstructure 200 from the imprinting device 100 after a single adhesion, the adhesion suppression part 3 is preferably formed such that the total contact area T is at least 1 / 100 times, preferably at least 1 / 50 times, and more preferably at least 1 / 30 times the area A of the holding surface 21. Furthermore, to suppress the adhesion of the microstructure 200 to the adhesion suppression part 3, the adhesion suppression part 3 is preferably formed such that the total contact area T is less than 1 / 2 times, preferably less than 1 / 5 times, and more preferably less than 1 / 10 times the area A of the holding surface 21. Moreover, this adjustment of the total contact area T can be achieved simply by adjusting the number or arrangement of the protrusions 4 of the adhesion suppression part 3, and the shape or area of ​​the adhesion suppression surface 41. Furthermore, by adjusting the number and arrangement of the protrusions in the adhesion suppression section, so that there are four or more protrusions in contact with the plane, preferably five or more, it becomes easier to retain small structures outside the pickup object that are accidentally attached. If the upper limit of the number is about 10, it is easy to achieve a balance between adhesion suppression and retention.

[0070] (3) Alternatively, the design can be based on the area A' of the held surface 201 of the microstructure 200. For example... Figure 3 As shown, when the microstructure 200 and the adhesion suppression part 3 are in contact at any position, the adhesion suppression part 3 can be designed using the ratio of the total contact area T' of the held surface 201 and the adhesion suppression surface 41 to the area A' of the microstructure 200. For example, in order to suppress the microstructure 200 from detaching from the imprinting device 100 after one adhesion, the adhesion suppression part 3 is preferably formed such that the total contact area T' is at least 1 / 100 times, preferably at least 1 / 50 times, and even more preferably at least 1 / 30 times the area A' of the microstructure 200. In addition, in order to suppress the microstructure 200 from adhering to the adhesion suppression part 3, the adhesion suppression part 3 is preferably formed such that the total contact area T' is less than 1 / 2 times, preferably less than 1 / 5 times, and even more preferably less than 1 / 10 times the area A' of the microstructure 200. Furthermore, the adjustment of this total contact area T' can be achieved simply by adjusting the number of protrusions 4 of the adhesion suppression part 3 and the shape or area of ​​the adhesion suppression surface 41.

[0071] (4) Alternatively, the adhesion-suppressing surface 41 may be made of a different material than the retaining surface 21. In this case, it is sufficient to design it using the ratio of the adhesive force of the materials constituting the retaining surface 21 and the adhesion-suppressing surface 41 to the product of their contact areas. If the adhesive forces of the materials constituting the retaining surface 21 and the adhesion-suppressing surface 41 are set to PA and PB, respectively, then in order to suppress the detachment of the microstructures 200 that have been attached once from the imprinting device 100, it is preferable to form a shape in which PA×A is at least 1 / 100 times, preferably at least 1 / 50 times, and even more preferably at least 1 / 30 times, of PB×B. In addition, in order to suppress the adhesion of the microstructures 200 to the adhesion-suppressing portion 3, it is preferable to form a shape in which PA×A is less than 1 / 2 times, preferably less than 1 / 5 times, and even more preferably less than 1 / 10 times, of PB×B.

[0072] Furthermore, the adhesion of the materials constituting the retaining surface 21 and the adhesion-inhibiting surface 41 is measured as follows.

[0073] First, a sample is formed in an aluminum petri dish with a material thickness of 1 mm constituting the holding surface 21 or adhesion-inhibiting surface 41. At this point, the surface of the sample is formed to be approximately horizontal. Furthermore, since the surface properties of the sample affect adhesion, it is kept smooth to prevent the presence of air bubbles or large bumps or tilts. Additionally, contact with the bonding surface or the adhesion of foreign matter is prevented, including during measurement, to prevent dust from adhering to the sample surface (bonding surface).

[0074] Next, at 23°C and 50% RH (relative humidity), double-sided adhesive tape (manufactured by Nitto Denko Corporation, product name: General Purpose Double-Sided Adhesive Tape No. 501F) was applied to the back of the aluminum petri dish and firmly fixed to the sample stage (lower pressure plate) of the Shimadzu EZ-SX mini benchtop testing machine. A 1 mm square prism-shaped stainless steel (SUS) probe, mounted on the testing machine, was pressed from top to bottom perpendicular to the sample surface (adhesive surface). This pressing applied a contact load of 1 MPa for 15 seconds after the probe made contact with the adhesive surface at a speed of 0.05 mm / s.

[0075] Subsequently, in the opposite direction of pressing, the probe is moved from below to above at a speed of 200 mm / min, perpendicular to the sample surface (adhesive surface), and the force required for the probe to peel off from the sample surface is measured. The maximum value measured is taken as the adhesive force. Five measurements are performed for a single sample, and the average adhesive force in each measurement is taken as the adhesive force in this invention.

[0076] Furthermore, the influence of the probe's surface properties on adhesion cannot be ignored in this measurement. Therefore, the material was set to SUS304, and the surface roughness was limited to approximately 250 nm to 500 nm in terms of root mean square roughness (Rq).

[0077] Furthermore, multiple protrusions 5 with adhesion-suppressing surfaces 51 can be formed on the side surface 25 connecting the base portion 1 and the holding surface 21. In this case, the height of the adhesion-suppressing surface 51 of the protrusion 5 is lower than the height of the holding surface 21. Therefore, when the microstructure 200 is held on the holding surface 21, it is possible to prevent the microstructure 200 from mistakenly attaching to the side surface 25 of the holding portion 2. When the side surface of the holding portion is not inclined relative to the surface of the base portion (substrate surface) (it is at a right angle), due to the pressure applied during the pick-up process, the holding portion deforms, and the side surface may sometimes come into contact with microstructures other than the pick-up target. However, by providing protrusions constituting adhesion-suppressing surfaces on the side surface, the pick-up of unwanted microstructures can be suppressed. Additionally, in cases such as... Figure 5 When the side is tilted relative to the base surface (substrate surface) (tilt angle less than 90 degrees, preferably 40 to 70 degrees), the deformation of the holding part caused by pressure is less likely to occur compared with the case where it is not tilted. However, since the distance between the small structure outside the pickup object and the side becomes closer, the protrusion that constitutes the adhesion suppression part provided on the side plays an effective role.

[0078] Furthermore, the transfer method of the present invention will be described. The transfer method of the present invention is a method for transferring a microstructure 200 using an imprinting apparatus, and mainly consists of a pick-up step and a detachment step. Furthermore, the imprinting apparatus 100 of the present invention can be used as the imprinting apparatus. For example, an imprinting apparatus can be used that includes a base portion 1 formed on a substrate 10; a holding portion 2 formed on the base portion 1, having a holding surface for holding the microstructure 200; and an adhesion suppression portion 3 formed on the base portion 1, having a plurality of protrusions 4 around the holding portion 2, the protrusions 4 having an adhesion suppression surface 41 with a height lower than the holding surface 21, such that when the microstructure 200 is attached to the adhesion suppression portion 3, the adhesion suppression portion 3 has an adhesive force that prevents the microstructure 200 from detaching under a force less than the weight of the microstructure 200.

[0079] The pick-up process is a process of contacting and holding the microstructure 200 with the holding surface 21 of the imprinting apparatus. For example, for one or more microstructures 200 that are arranged in large quantities on the supply substrate, they are brought into contact with the holding surface 21 of the imprinting apparatus and pressure is applied to attach the microstructures 200 to the holding surface 21. Next, if the imprinting apparatus is separated from the supply substrate, the microstructures 200 can be picked up and held on the holding surface 21 of the imprinting apparatus.

[0080] The detachment process is the process of detaching the microstructure 200 from the holding surface 21 of the imprinting apparatus. The detachment process can be performed using any method as long as it allows the microstructure 200 to be detached from the holding surface 21 of the imprinting apparatus. For example, a film with a stronger adhesive force than the holding surface 21 of the imprinting apparatus can be formed on the receiving substrate. Then, the microstructure 200, which has been held on the holding surface 21 of the imprinting apparatus by a pick-up process, is pressed onto the receiving substrate. Subsequently, by separating the imprinting apparatus from the receiving substrate, the microstructure 200 held on the holding surface 21 of the imprinting apparatus can be detached.

[0081] Furthermore, it is preferable to have a removal process capable of removing the microstructures 200 from the adhesion inhibition surface 41. The removal process can be performed in any manner as long as it can remove the microstructures 200 from the adhesion inhibition surface 41; for example, wet cleaning or dry cleaning can be performed. For example, as a wet cleaning method, a method of immersing the imprinting device in an isopropanol bath and applying ultrasound can be used. Alternatively, as a dry cleaning method, supercritical CO2 cleaning can be used.

[0082] Therefore, the microstructures 200 attached to the adhesion inhibition surface 41 can be removed.

[0083] Thus, when tiny structures outside the pickup target adhere to the adhesion suppression surface, these structures remain attached to the adhesion suppression surface until the removal process, thereby suppressing contamination of the system environment, such as the transfer path. Micro-LEDs, mini-LEDs, and other tiny structures are extremely small, and even if they detach and contaminate the system environment along the transfer path, identification is difficult. They may accidentally adhere to or become entangled in other components or devices such as imprinting devices, supply substrates, and receiving substrates, leading to further defects. Therefore, it is preferable to control all tiny structures that accidentally detach from the supply substrate. On the other hand, even if only some detached tiny structures are controlled, system environment contamination can still be reduced.

[0084] Thus, by keeping the tiny structures outside the pick-up object that have detached from the supply substrate in the imprinting apparatus until the removal process, their recovery can be efficiently concentrated in the removal process, thereby reducing the potential risks and the time required for their clarification.

[0085] In addition, the picking and removing processes can be repeated multiple times before the removal process, or other processes can be inserted.

[0086] Another transfer method of the present invention is a method for transferring microstructures 200 using an imprinting apparatus that picks up both the microstructure 200 to be transferred and other microstructures 200. This method mainly consists of a picking step and a transfer step. Furthermore, the imprinting apparatus 100 of the present invention can be used as the imprinting apparatus. For example, an imprinting apparatus can be used that includes a base portion 1 formed on a substrate 10; a holding portion 2 formed on the base portion 1, having a holding surface 21 for holding the microstructure 200; and an adhesion suppression portion 3 formed on the base portion 1, around the holding portion 2, having a plurality of protrusions 4, the protrusions 4 having an adhesion suppression surface 41 with a height lower than the holding surface 21.

[0087] The pick-up process is a process of holding the microstructure 200, which is to be transferred, in the holding part 2. For example, for one or more microstructures 200 that are arranged in large quantities on the supply substrate, they are brought into contact with the holding surface 21 of the imprinting apparatus and pressure is applied, so that the microstructures 200 are attached to the holding surface 21. Next, if the imprinting apparatus is separated from the supply substrate, the microstructures 200 can be picked up and held in the holding surface 21 of the imprinting apparatus.

[0088] The transfer process is a process of transferring the microstructure 200, which is the object of transfer, held in the holding part 2. For example, it is a process in which the microstructure 200 is picked up from the supply substrate and then the microstructure 200 held in the holding part 2 is transferred from the supply substrate to the receiving substrate until the microstructure 200 is placed on the receiving substrate.

[0089] Here, when the microstructure 200 other than the transfer object is held in the adhesion suppression part 3 during the pick-up process, the adhesion force of the adhesion suppression part 3 is controlled so that the microstructure 200 other than the transfer object held in the adhesion suppression part 3 continues to be held in the adhesion suppression part 3 during the transfer process. Regarding the control of adhesion force, for example, it is only necessary to adjust the adhesion force of the adhesion suppression surface, or, as in the imprinting apparatus 100 of the present invention, adjust the number of protrusions 4 of the adhesion suppression part 3, the shape or area of ​​the adhesion suppression surface 41.

[0090] Additionally, a removal process may be included to remove the microstructures 200 that remain attached to the adhesion inhibition section 3, excluding the transfer object. In this case, the adhesion force of the adhesion inhibition section 3 or the removal force of the removal process is controlled to remove the microstructures 200 other than the transfer object through the removal process. The removal process can be performed in any manner as long as the microstructures 200 can be removed from the adhesion inhibition surface 41, such as wet cleaning or dry cleaning.

[0091] The transfer method of the present invention is applicable to manufacturing methods of electrical-electronic application products that include processes for transferring microstructures using the transfer method. Furthermore, the transfer method of the present invention can also be applied to manufacturing methods of displays that include processes for transferring microstructures using the transfer method.

[0092] Each component in the plurality of embodiments can be refined, and the refined components can be individually or in combination introduced into (X1) to (X18). Furthermore, the refined components or combinations thereof can function as inventions to realize their respective mechanisms. In such cases, other components that do not substantially contribute to the realization of the mechanism can naturally be excluded as features of the invention. Representative examples include components such as a substrate, base portion, holding portion, adhesion suppression portion, protrusion constituting the adhesion suppression portion, holding surface, adhesion suppression surface, and side surface, as well as their materials, shapes, dimensions, arrangements, and relationships.

[0093] Explanation of icon numbers

[0094] 1: Base section

[0095] 2: Maintaining section

[0096] 3: Adhesion inhibition section

[0097] 4: convex part

[0098] 5: convex part

[0099] 10: Substrate

[0100] 21: Keep the surface

[0101] 25: Side view

[0102] 41: Adhesion suppression surface

[0103] 51: Adhesion suppression surface

[0104] 100: Imprinting device

[0105] 200: Microstructures

[0106] 300: Plane

Claims

1. An imprinting apparatus for transferring microstructures, the imprinting apparatus characterized in that it comprises: The base portion is formed on the substrate; A retaining portion is formed on the base portion and has a retaining surface for retaining the microstructure; as well as An adhesion-inhibiting portion is formed around the retaining portion on the base portion, and has a plurality of protrusions, the protrusions having an adhesion-inhibiting surface with a height lower than the retaining surface. When the microstructure is attached to the adhesion-inhibiting part, the adhesion-inhibiting part is formed to have an adhesive force that prevents the microstructure from falling off under a force less than the weight of the microstructure itself.

2. An imprinting apparatus for transferring microstructures, the imprinting apparatus characterized by comprising: The base portion is formed on the substrate; A retaining portion is formed on the base portion and has a retaining surface for retaining the microstructure; as well as An adhesion-inhibiting portion is formed around the retaining portion on the base portion, and the protrusions have an adhesion-inhibiting surface with a height lower than the retaining surface. The area B of the adhesion-inhibiting surface is more than 1 / 100 times the area A of the retaining surface.

3. The embossing device according to claim 2, characterized in that The area B of the adhesion-inhibiting surface is less than 1 / 2 of the area A of the retaining surface.

4. An imprinting apparatus for transferring microstructures, the imprinting apparatus characterized in that it comprises: The base portion is formed on the substrate; A retaining portion is formed on the base portion and has a retaining surface for retaining the microstructure; as well as An adhesion-inhibiting portion is formed around the retaining portion on the base portion, and the protrusions have an adhesion-inhibiting surface with a height lower than the retaining surface. The adhesion-suppressing part has the following shape: when a plane with the same shape as the retaining surface contacts the adhesion-suppressing part at any position, the total contact area T between the plane and the adhesion-suppressing surface is more than 1 / 100 times the area A of the retaining surface.

5. The embossing device according to claim 4, characterized in that The adhesion-suppressing part has the following shape: when a plane with the same shape as the retaining surface contacts the adhesion-suppressing part at any position, the total contact area T between the plane and the adhesion-suppressing surface is less than 1 / 2 times the area A of the retaining surface.

6. An imprinting apparatus for transferring microstructures, the imprinting apparatus characterized in that it comprises: The base portion is formed on the substrate; A retaining portion is formed on the base portion and has a retaining surface for retaining the microstructure; as well as An adhesion-inhibiting portion is formed around the retaining portion on the base portion, and the protrusions have an adhesion-inhibiting surface with a height lower than the retaining surface. The adhesion suppression part has the following shape, that is, when the microstructure and the adhesion suppression part are in contact at any position, the total contact area T' with the adhesion suppression surface is more than 1 / 100 times the area A' of the microstructure.

7. The embossing device according to claim 6, characterized in that The adhesion suppression part has the following shape: when the microstructure is in contact with the adhesion suppression part at any position, the total contact area T' with the adhesion suppression surface is less than 1 / 2 times the area A' of the microstructure.

8. An imprinting apparatus for transferring microstructures, the imprinting apparatus characterized in that it comprises: The base portion is formed on the substrate; A retaining portion is formed on the base portion and has a retaining surface for retaining the microstructure; as well as An adhesion-inhibiting portion is formed around the retaining portion on the base portion, and the protrusions have an adhesion-inhibiting surface with a height lower than the retaining surface. The product of the adhesion force and area of ​​the adhesion-inhibiting surface is more than 1 / 100 times the product of the adhesion force and area of ​​the retaining surface.

9. The imprinting apparatus according to claim 8, characterized in that... The product of the adhesion force and area of ​​the adhesion-inhibiting surface is less than 1 / 2 times the product of the adhesion force and area of ​​the retaining surface.

10. An imprinting apparatus for transferring microstructures, the imprinting apparatus characterized in that it comprises: The base portion is formed on the substrate; as well as A retaining portion, formed on the base portion, has a retaining surface for retaining the microstructure. On the side connecting the base portion to the retaining surface, there are multiple protrusions, each protrusion having an adhesion-inhibiting surface with a height lower than the retaining surface.

11. The embossing apparatus according to claim 9, characterized in that... At least a portion of the retaining part is cylindrical, prismatic, frustum conical, or frustum pyramidal, or a shape formed by beveling a portion of these shapes.

12. A holding portion, as a component of an imprinting apparatus for transferring minute structures, characterized in that, This includes a holding surface for holding the microstructure, and a side surface extending toward the surface opposite to the holding surface. The side has multiple protrusions, each protrusion having an adhesion-inhibiting surface.

13. A transfer method for transferring microstructures using an imprinting apparatus, the transfer method being characterized by having: The pickup process holds the microstructure on the holding surface of the imprinting device; as well as In the detachment process, the microstructure is detached from the holding surface of the imprinting device. The imprinting apparatus includes: A base portion is formed on a substrate; a retaining portion is formed on the base portion and has a retaining surface for retaining the microstructure. And an adhesion-inhibiting portion, which is formed around the retaining portion on the base portion, has a plurality of protrusions, the protrusions having an adhesion-inhibiting surface with a height lower than the retaining surface, such that when the microstructure is attached to the adhesion-inhibiting portion, the adhesion-inhibiting portion has an adhesive force that prevents the microstructure from falling off under a force less than the weight of the microstructure itself.

14. The transfer method according to claim 13, characterized in that... It has a removal process capable of removing the microstructures from the adhesion inhibition surface.

15. A transfer method, which utilizes an imprinting device to pick up a microstructure as the transfer target and microstructures other than the transfer target, characterized in that... The imprinting apparatus includes: a base portion formed on a substrate; a holding portion formed on the base portion, having a holding surface for holding the microstructure; and an adhesion-suppressing portion formed on the base portion, having a plurality of protrusions around the holding portion, the protrusions having an adhesion-suppressing surface with a height lower than the holding surface. The transfer method includes: a picking step of holding the microstructure to be transferred in the holding portion; and a transfer step of transferring the microstructure to be transferred from the holding portion. During the picking process, the minute structures other than the transfer object remain in the adhesion inhibition section. The adhesion of the adhesion inhibition portion is controlled so that the small structures that are held outside the transfer object in the adhesion inhibition portion continue to remain in the adhesion inhibition portion during the transfer process.

16. The transfer method according to claim 15, characterized in that... It also includes a removal process that removes microstructures other than the transfer object that remain in the adhesion inhibition section, and controls the adhesion of the adhesion inhibition section or the removal force of the removal process to remove the microstructures other than the transfer object through the removal process.

17. A transfer method, characterized in that, The microstructure is transferred using the imprinting apparatus as described in any one of claims 1 to 11.

18. A method for manufacturing an electrical-electronic application product, comprising a step of transferring a microstructure using the transfer method as described in claim 17.

19. A method for manufacturing an electrical-electronic application product, comprising a step of transferring a microstructure by a transfer method as described in any one of claims 13 to 16.

20. A method of manufacturing a display, comprising a step of transferring a microstructure by means of the transfer method as described in claim 17.

21. A method of manufacturing a display, comprising a step of transferring a microstructure by a transfer method as described in any one of claims 13 to 16.

22. A holding method for holding minute structures outside the pickup object in an imprinting apparatus, wherein... The imprinting apparatus includes: A base portion is formed on a substrate; a retaining portion is formed on the base portion and has a retaining surface for retaining the microstructure. And an adhesion-inhibiting portion, formed around the retaining portion on the base portion, having a plurality of protrusions, the protrusions having an adhesion-inhibiting surface with a height lower than the retaining surface. The holding method includes: a picking step, in which a microstructure, disposed on a supply substrate and designated as a picking target, is held on the holding surface of the imprinting apparatus; and a removing step, in which the microstructure, designated as a picking target, held on the holding surface is removed from the holding surface and transferred to a receiving substrate. In the picking process, a small structure outside the picking object that has detached from the supply substrate is attached to the adhesion suppression section. While the small structure outside the picking object is held in the imprinting device, a detachment process is performed. In a subsequent removal process, the small structure outside the picking object held in the imprinting device is removed from the adhesion suppression surface.

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