Holding member and holding device

Abstract

A holding member 1 is provided with a holding layer (10) having a Martens hardness of a portion in contact with an object that is held of 20-300 N / mm2, and a base material (20) that supports the holding layer (10).

Description

Retaining member and retaining device

[0001] This disclosure relates to a retaining member and a retaining device.

[0002] Conventionally, in electronic circuit mounting processes, semiconductor manufacturing processes, etc., when mounting electronic components onto workpieces such as thin printed circuit boards and flexible circuit boards, a technique is known in which the workpiece is attracted by electrostatic force generated by an applied voltage, as described in Japanese Patent Publication No. 2019-47643 (JP2019-47643A).

[0003] Here, the electrostatic attraction force of the object to be held, such as a semiconductor wafer, may decrease depending on the processing environment of the object to be held.

[0004] This disclosure has been made with these points in mind and aims to provide a new retaining member and retaining device that maintain or improve the retaining force on the object to be held.

[0005] The retaining member of this disclosure has a Martens hardness of 20 to 300 N / mm² at the portion that contacts the object to be held. 2 The present invention is characterized by comprising a retaining layer and a substrate that supports the retaining layer.

[0006] Furthermore, the retaining member of this disclosure includes an adhesion layer that brings the retaining layer and the substrate into close contact, and the Martens hardness of the substrate, the retaining layer and the adhesion layer may be in the relationship: substrate > retaining layer > adhesion layer.

[0007] Furthermore, in the holding member of this disclosure, the mean square surface roughness of the portion of the holding layer that contacts the object to be held is 10 nm / μm 2 The following is also acceptable.

[0008] Furthermore, in the retaining member of this disclosure, the retaining layer may have at least one property selected from the group consisting of plasma resistance, chemical resistance, heat resistance, water resistance, and stain resistance.

[0009] Furthermore, in the retaining member of this disclosure, the retaining layer may include a polyimide resin, a polyamide resin, or a polyolefin resin.

[0010] Furthermore, in the holding member of this disclosure, the base material may be provided with electrodes.

[0011] Furthermore, in the retaining member of this disclosure, the base material may be stretchable.

[0012] Furthermore, in the retaining member of this disclosure, the elongation rate of the retaining layer may be 1 to 15%.

[0013] Furthermore, in the holding member of this disclosure, the elongation rate of the base material may be 5 to 450%.

[0014] Furthermore, in the holding member of this disclosure, the Martens hardness of the base material is 10 to 110 N / mm². 2 That's fine.

[0015] The holding device of this disclosure is characterized by comprising the above-described holding member and an adhesion mechanism for bringing an object to be held into close contact with the holding layer.

[0016] Furthermore, the holding device of this disclosure preferably includes a detachment mechanism for attaching and detaching an object to be held by the holding member.

[0017] This is a cross-sectional view showing the schematic configuration of a retaining member according to an embodiment of the present disclosure. This is a cross-sectional view showing another schematic configuration of a retaining member according to an embodiment of the present disclosure. This is an explanatory diagram showing the surface roughness of the retaining layer of a retaining member according to an embodiment of the present disclosure. This is a cross-sectional view showing the schematic configuration of a retaining member according to another embodiment of the present disclosure. This is a schematic diagram showing an exemplary state when an object to be held is attached to or detached from a retaining member according to another embodiment of the present disclosure.

[0018] Embodiments of this disclosure will be described below with reference to the drawings. Note that the drawings are for illustrative purposes only, and the inventions described herein are not limited to the shape, arrangement, dimensions, proportions, etc., of each component shown.

[0019] <<Embodiment 1>> [Holding Member 1]FIGS. 1 and 2 are cross-sectional views showing the schematic configuration of a holding member according to an embodiment of the present disclosure. The holding member 1 of the present disclosure holds an object to be held (object to be held). As shown in FIG. 1, the holding member 1 includes a holding layer 10 and a base material 20. Further, the holding member 1 may include an adhesion layer 30 (FIG. 2). Hereinafter, these components will be described. The "object to be held" may include so-called wafers (such as silicon wafers, quartz wafers, SiC wafers, etc.), flat panel display (FPD) panels and substrates, metal members, film members, resin members (such as automotive interior materials), glass members, etc. workpieces, and further foreign substances such as dust and resin fragments, but is not particularly limited. When holding foreign substances, the holding member of the present invention can be used for the purpose of removing foreign substances.

[0020] (Holding Layer 10) In the holding member 1, the object to be held is held by the holding layer 10. The martensite hardness of the holding layer 10 (specifically, the portion in contact with the object to be held) at 25°C is 20 to 300 N / mm 2 and preferably 100 to 260 N / mm 2 , more preferably 150 to 230 N / mm 2 is. As a result of intensive studies by the present inventors, it has been found that materials with low martensite hardness (soft materials) tend to adhere easily, and materials with high martensite hardness (hard materials) tend to adhere poorly. Further, based on this finding, it was conceived that if the martensite hardness is within the above range, the holding layer 10 can hold the object to be held well and can be detached (act as a separation functional layer). For example, it can be expected that, apart from the use or action of electrostatic force (Coulomb force) in the semiconductor manufacturing process, the holding force for the object to be held can be maintained or improved (the object to be held does not peel off during the process, and further, the object to be held can be peeled off after the process). Regarding the peeling of the object to be held from the holding layer 10, the martensite hardness of the holding layer 10 at 25°C is 20 N / mm 2 or more, preferably 100 N / mm 2 or more, further 150 N / mm 2 or more, more preferably 180 N / mm 2That concludes the explanation. On the other hand, focusing on the adhesion of the object to be held to the holding layer 10, the Martens hardness of the holding layer 10 is 300 N / mm². 2 Preferably, 230 N / mm 2 Less than, more preferably 160 N / mm 2 It is less than.

[0021] Martens hardness can be measured as follows. For example, a test piece of the retaining layer 10 is cut to a size that can be placed on the sample stage of a nanoindenter device (for example, the ENT series manufactured by Elionix Co., Ltd.), and fixed to a glass plate with adhesive. Then, the Martens hardness can be calculated from the reaction force generated when an indenter is inserted into the test piece.

[0022] The retaining layer 10 may be composed of multiple components (layers, materials). For example, the retaining layer 10 can be composed of a surface layer 12, which is located on the outer surface (opposite side from the base material 20), and an intermediate layer 14, which is another layer (see Figure 2). Here, based on the location (depth) where the Martens hardness is measured, the retaining layer 10 is divided into a surface layer 12 and an intermediate layer 14, and the part of the retaining layer 10 where the Martens hardness is measured is called the surface layer 12. That is, the Martens hardness of the retaining layer 10 is the same as the Martens hardness of the surface layer 12. The surface layer 12 and the intermediate layer 14 may be formed from the same material, or they may be formed from multiple different materials. That is, the surface layer 12 may be formed from multiple materials, but the Martens hardness of the retaining layer 10 (surface layer 12) will be based on actual measurement.

[0023] Furthermore, the portion for measuring Martens hardness (i.e., the portion in contact with the object to be held) may be the entire outer surface (surface layer 12) of the holding layer 10, but it is preferable that the portion having the predetermined Martens hardness described above occupies 50% or more of the area of ​​the surface layer 12. In other words, if the Martens hardness is within the range of 50% to 100% of the area of ​​the surface layer 12, the effects discovered by the inventors are suitably exhibited.

[0024] The retaining layer 10 can hold and release the object to be held even if it is flat, but it may also have irregularities expressed as mean square roughness. Figure 3 shows a schematic example of such irregularities (unit: μm). In this case, the mean square roughness of the portion of the retaining layer 10 that contacts the object to be held (surface layer 12) is 10 nm / μm. 2 Preferably, the following, and more preferably, 2.0 to 10.0 nm / μm 2 More preferably 5.0 to 10.0 nm / μm 2 And more preferably 5.0 to 8.0 nm / μm 2 In this specification, the mean square surface roughness is the value measured using an atomic force microscope in a 20 μm square area at any 10 locations on the retaining layer 10.

[0025] More specifically, from the viewpoint of holding and releasing the object to be held, in order to suitably exert the holding force by the holding member 1, the mean square surface roughness of the portion of the holding layer 10 that comes into contact with the object to be held should be 10 nm / μm 2 The following is preferred: 5.0 nm / μm 2 The following is preferred: 2.5 nm / μm 2 The following is more preferable. On the other hand, focusing on peeling of the object to be held from the holding layer 10, the mean square surface roughness is 0.5 nm / μm 2 The above is preferred, and 1.0 nm / μm 2 The above is even more preferable.

[0026] The material of the retaining layer 10 is not particularly limited as long as it has a Martens hardness within the range described above, but it may include polyimide resins, polyamide resins, or polyolefin resins, and the retaining layer 10 may also be a mixture thereof.

[0027] The holding layer 10 (including the surface layer 12 and the intermediate layer 14) can have at least one property selected from the group consisting of plasma resistance, chemical resistance, heat resistance, water resistance, and stain resistance. In order to impart these functionalities, the following (1) to (4) can be cited as the configuration of the holding layer 10. (1) It includes a thin film containing particles such as alumina, yttria, and zirconia, or composed of the above particles. (2) It contains at least one of PFA (perfluoroalkoxyethylene), PVDF (polyvinylidene fluoride), and PTFE (polytetrafluoroethylene). (3) It contains at least one of PPS (polyphenylene sulfide), PEKK (polyether ketone ketone), and PEEK (polyether ether ketone). (4) It is formed by at least one of polyimide, polyamide, and polyamideimide. When the holding layer 10 has plasma resistance, it is preferably the above (1). When the holding layer 10 has chemical resistance, it is preferably the above (2). When the holding layer 10 has heat resistance, it is preferably at least any one of the above (1) to (4). When the holding layer 10 has water resistance, it is preferably at least any one of (2) to (4). When the holding layer 10 has stain resistance, it is preferably the above (2). These properties may be based not only on the material of the holding layer 10 used, but also on other materials (such as additives and fillers) added to the holding layer 10. In addition, when the holding layer 10 is provided with adhesiveness to the base material 20, the adhesion layer 30 described later will be provided on the holding member 1.

[0028] The shape of the holding layer 10 is not particularly limited, and it may be circular or square according to the shape of the object to be held. Dimensions such as the thickness of the holding layer 10 are also not particularly limited as long as the object to be held can be detached, but for example, the thickness of the holding layer 10 can be set to 0.1 to 100 μm.

[0029] (Base Material 20) In the holding member 1, the holding layer 10 is supported by the base material 20. As long as the holding layer 10 can be supported, the material, shape, dimensions, etc. of the base material 20 are not particularly limited, and it may have through-holes H (Fig. 2). The thickness of the base material 20 can be 50 μm to 1000 μm. Note that by using the through-holes H, hot air or cooling gas can be supplied to the holding layer 10, or lifting pins for lifting the holding layer 10 can be actuated.

[0030] The base material 20 can also include electrodes. Examples of the electrodes include electrodes that form a heater, electrodes that exhibit an electrostatic adsorption force when a voltage is applied, electrodes for plasma generation, etc. Such electrodes include, for example, thin films made of metals such as copper, aluminum, gold, silver, platinum, chromium, nickel, tungsten, and thin films made of at least two metals selected from these metals.

[0031] (Adhesive Layer 30) The adhesive layer 30 adheres the holding layer 10 and the base material 20. Also, the adhesive layer 30 functions as a buffer layer. Further, the adhesive layer 30 can also relax the CTE (coefficient of thermal expansion) difference between the holding layer 10 and the base material 20 and suppress delamination of the holding layer 10. As long as the holding layer 10 and the base material 20 can be adhered, the material, shape, dimensions, etc. of the adhesive layer 30 are not limited.

[0032] It is preferable that the martensitic hardness (25°C) of the base material 20, the holding layer 10, and the adhesive layer 30 is in the relationship of base material 20 > holding layer 10 > adhesive layer 30. Examples of the material of the base material 20 in this case include metals such as aluminum, stainless steel, copper, and non-metals such as silicon, silicon carbide, aluminum nitride, alumina, glass, etc. Examples of the material of the adhesive layer 30 include epoxy resin, polyimide resin, polyamide resin, polyamideimide resin, polyurethane resin, polyester resin, etc. Note that when there is an intermediate layer 14, its martensitic hardness is also lower than that of the base material 20 and higher than that of the adhesive layer 30.

[0033] (Manufacturing method and application of the retaining member 1) The retaining member 1 can be manufactured as follows, for example. First, a base material 20 is prepared. At this time, electrodes for heating or electrostatic adsorption may be provided inside the base material 20 by pattern forming a metal such as copper. Next, the base material 20 and the retaining layer 10 can be brought into close contact via an adhesive layer 30 to manufacture the retaining member 1.

[0034] The holding member 1 can be used, for example, to hold a wafer or other object to be held in dry etching or CVD processes in semiconductor manufacturing. In particular, when electrostatic force is also used to hold the object to be held in apparatus or methods using plasma, even if the electrostatic force decreases, or even if the object to be held is made of a material that is not affected by electrostatic force, the holding force of the holding member 1 according to this disclosure will improve in the high-temperature state caused by plasma irradiation, and the object to be held placed and pressed on the holding member 1 can be held. Furthermore, as the temperature of the holding layer 10 decreases, the holding force of the holding layer 10 decreases, as a result, the object to be held can be easily peeled off the holding layer 10.

[0035] [Holding device] The holding device according to this disclosure comprises the holding member 1 and an adhesion mechanism for bringing an object to be held into close contact with the holding layer.

[0036] (Adhesion Mechanism) The object to be held is brought into close contact with the holding layer 10 by the adhesion mechanism, thereby allowing the object to be held to be suitably held by the holding member 1. The adhesion mechanism is not particularly limited as long as it brings the object to be held into close contact with the holding layer 10, but it is preferable that the object to be held is brought into contact with the holding layer 10 with pressure.

[0037] Means for bringing the object to be held into close contact with the holding layer 10 include, for example, (1) generating pressure on the object to be held by a fluid such as air, a mechanical mechanism (pressing unit, press, etc.), or electrostatic attraction, and (2) removing the air between the object to be held and the holding layer 10 by depressurizing in order to bring the object to be held and the holding member 1 into close contact.

[0038] (Detachment Mechanism) The holding device may further have a detachment mechanism for attaching and detaching the object to be held by the holding member 1. Alternatively, the detachment mechanism may be operated automatically by a detachment control unit. In this specification, the detachment mechanism creates a gap between the object to be held and the holding member.

[0039] As a detachment mechanism, if an electrostatic force is applied to the object to be held by electrodes provided on the base material 20, causing the object to adhere tightly, a mechanism to remove the electrostatic force can be provided. In this case, the adhesion mechanism and the detachment mechanism can be integrated. Another example of an integrated detachment mechanism is a combination of a unit that attaches the object to be held to the holding member 1 and a unit that removes the object from the holding member 1. An example of the former is a unit that applies pressure (pressure) to the object to be held. An example of the latter is a unit that physically moves the holding member 1 and the object to be held using a through hole H.

[0040] Furthermore, a cooling mechanism can be used as a detachment mechanism. The cooling mechanism cools the holding layer 10 and the object to be held. The cooling method is not particularly limited and may involve blowing air onto the object to be held from above, the side, or below, or supplying cold air, cooling gas, heat transfer gas, etc., through the through-hole H. Cooling of the holding member 1 and the entire holding device (including the atmosphere inside the housing) may also be the objective. Known coolers can be used as the cooling mechanism. The object to be held can be detached by utilizing the difference in the coefficients of linear expansion between the holding layer 10 and the object to be held. In this case, it is preferable to employ a cooling mechanism because one can be easily detached by contracting it more than the other through cooling.

[0041] (Heating Mechanism) The holding device may also be equipped with a heating mechanism. The heating mechanism heats the object to be held by the holding member 1, and the heating method may involve heating from above, the side, or below the object to be held. Heating the holding member 1 or the entire holding device (including the atmosphere inside the housing) may also be the objective. The heating mechanism may be a heater composed of electrodes provided on the base material 20 as described above, or a known heater can be used.

[0042] According to the holding member 1 and holding device of this embodiment, which have the above configuration, the Martens hardness (25°C) of the portion in contact with the object to be held is 20 to 300 N / mm 2 A retaining layer 10 and a base material 20 that supports the retaining layer 10 are provided. The retaining device of this disclosure is also provided with a retaining member 1 and an adhesion mechanism that brings the object to be held into close contact with the retaining layer 10. With such a retaining member 1 and retaining device, it is possible to provide a new retaining member and retaining device that maintain or improve the retaining force on the object to be held.

[0043] Furthermore, the holding member 1 and holding device of this embodiment may also be provided with an adhesion layer 30 that brings the holding layer 10 and the base material 20 into close contact. Preferably, the Martens hardness (25°C) of the base material 20, the holding layer 10, and the adhesion layer 30 are in the relationship base material 20 > holding layer 10 > adhesion layer 30. In this way, having the adhesion layer 30 as the softest makes it easier to hold the object to be held more securely. On the other hand, if the relationship is base material 20 > adhesion layer 30 > holding layer 10, the Martens hardness of the adhesion layer is higher than that of the holding layer, making it difficult for the holding layer to deform and easier to peel off the object to be held.

[0044] Furthermore, in the holding member 1 and holding device of this embodiment, the mean square surface roughness of the portion of the holding layer 10 that comes into contact with the object to be held (surface layer 12) is 10 nm / μm 2 The following is also possible: The holding force and release properties to the object to be held can be adjusted by adjusting the surface roughness of the holding layer 10 (surface layer 12). The method of adjusting the surface roughness is not particularly limited, and for example, the surface roughness can be adjusted by treatment with abrasives or chemicals, embossing, matte treatment, etc. Furthermore, the surface roughness and holding force can also be adjusted by partially hardening the holding layer 10 (surface layer 12). The means of hardening are not limited, and heat curing, UV curing, gas curing such as the carbon dioxide method, moisture curing, etc. can be used. For example, heat curing can be performed by applying a heating plate equipped with a heating part and a cooling part to the holding layer 10.

[0045] Furthermore, in the holding member 1 and holding device of this embodiment, the holding layer 10 may have at least one property selected from the group consisting of plasma resistance, chemical resistance, heat resistance, water resistance, and stain resistance. In this way, the holding layer 10 may be given desired properties in accordance with the treatment applied to the object to be held.

[0046] Furthermore, in the retaining member 1 and retaining device of this embodiment, the retaining layer 10 may contain a polyimide resin, a polyamide resin, or a polyolefin resin. These materials are preferred from the viewpoint of plasma resistance and heat resistance.

[0047] Furthermore, in the holding member 1 and holding device of this embodiment, the base material 20 may be provided with electrodes. By utilizing such electrodes, the base material 20 can also function as a member that generates electrostatic force or as a heater, etc.

[0048] Furthermore, in a holding device according to one embodiment of the present disclosure, it is preferable that a detachment mechanism is provided for attaching and detaching an object to be held by the holding member 1. In this way, after processing on the holding member 1, the object to be held can be moved and a series of processes can be carried out.

[0049] However, the retaining member 1 and retaining device according to this embodiment are not limited to the above-described configurations or combinations.

[0050] The present disclosure will be described in more detail below with reference to examples.

[0051] (Examples 1-12, Comparative Examples 1-3) Retaining members were manufactured using materials (retaining layer, adhesion layer, base material) having the thickness and characteristics shown in Table 1. The size of the retaining layer, adhesion layer, and base material was all 100 x 100 mm, and the thickness was as described in Table 1.

[0052] In Examples 1-4 and 8-12, the retaining layer material was prepared using a mixture of thermoplastic polyimide and thermosetting epoxy resin to achieve the Martens hardness (25°C) shown in Table 1. In Examples 5-7, a mixture of thermoplastic elastomer (polymer of polystyrene, polyethylene, and polybutylene) and thermosetting epoxy resin was prepared to achieve the Martens hardness shown in Table 1. In Comparative Example 1, silicone rubber was used; in Comparative Example 2, an acrylic polymer (adhesive); and in Comparative Example 3, a UV-curable resin (polyfunctional acrylate) was used, all prepared to achieve the Martens hardness shown in Table 1.

[0053] As the material for the adhesion layer, an acrylic adhesive was used in Example 9, and an epoxy resin was used in Example 10. In addition, glass was used as the substrate material in all examples and comparative examples.

[0054] Thickness was measured using a contact-type film thickness gauge. Martens hardness was measured using a nanoindenter (Elionix Corporation ultra-micro indentation hardness tester), mean square surface roughness was measured using an atomic spectroscopy (AFM) (Hitachi High-Tech Corporation), and Young's modulus (25°C, tensile modulus) was measured using a thermomechanical analyzer (TMA) (Shimadzu Corporation).

[0055] [Evaluation Method] The following adsorption and peel tests were performed on each holding member. A silicon wafer cut to 25 x 25 mm and 300 μm thick was used as the holding material.

[0056] (Adsorption Test) Each holding member was heated to 100°C, and a silicon wafer was pressed against the holding member with a force of 10N for 10 seconds. Those in which the silicon wafer could be adsorbed by this pressure were evaluated as "○", "○○", or "○○○○", and those in which it could not be adsorbed were evaluated as "×". Here, "adsorption" refers to a state in which the silicon wafer (object to be held) and the holding layer are stuck to each other. In Comparative Example 3, where adsorption was not possible, the silicon wafer was simply placed on top of the holding member. Even when the silicon wafer and the holding layer were adsorbed, there were areas where gaps remained. The area ratio of areas that were in close contact (no gaps) (adsorption performance, adsorption area ratio) was calculated using the following formula, and each holding member was evaluated as "○", "○○", or "○○○○" according to this area ratio. Area ratio = 100 × (area of ​​areas in close contact) / total area of ​​the object to be held. "○" refers to an area ratio of 20-50%, "○○" refers to an area ratio of 51-80%, and "○○○○" refers to an area ratio of 81-100%. The "area of ​​contact" between the retaining layer and the object being held was calculated by image processing (binarization) of the measurement sample. Specifically, if the distance between the retaining layer and the object being held was less than 10 μm, it was considered that there was no gap (contact), and if the distance between them exceeded 10 μm, it was considered that there was a gap, and binarization was performed.

[0057] (Peel Test) After the adsorption test, the force required to peel the silicon wafer from each holding member was measured. Specifically, the peel force was measured using Tensilon (A&D Co., Ltd., RTC series) (25°C). The entire surface of the object to be held was attached to a measuring probe connected to a load cell, and peeled at a speed of 50 mm / min at a 90° angle. Objects that could be peeled were evaluated as "○", "○○", or "○○○○", while those that could not be peeled were evaluated as "×". "○" means a peel force of 20 gf or more and less than 50 gf, "○○" means a peel force of 10 gf or more and less than 20 gf, and "○○○○" means a peel force of 0.1 or more and less than 10 gf. In other words, "○○" and "○○○○" are particularly preferred because the object to be held can be peeled with less force. In Comparative Example 3, the silicon wafer was simply placed in the adsorption test, so no peel test was performed and it was evaluated as "unacceptable".

[0058]

[0059] As shown in Table 1, the Martens hardness of the portion in contact with the object being held is 20 to 300 N / mm². 2 The retaining members (Examples 1 to 12), which comprise a retaining layer and a substrate supporting the retaining layer, showed a better area ratio (adsorption) between the object to be held and the retaining layer in the adsorption test compared to the retaining member (Comparative Example 3) whose Martens hardness was not within the above range. This suggests that the present disclosure can provide new retaining members and retaining devices that maintain or improve the retaining force on the object to be held.

[0060] Furthermore, in Comparative Examples 1-2, a high area ratio (adsorption) was observed between the object to be held and the holding layer in the adsorption test, but the silicon wafer could not be peeled off the holding member in the peel test.

[0061] In contrast, the retaining members of Examples 1 to 12 not only showed good adsorption in the adsorption test, but also showed good peelability in the peel test. From these results, it can be seen that the retaining members of Examples 1 to 12 are all more practical than the retaining members of Comparative Examples 1 to 3.

[0062] Furthermore, focusing on Examples 1 to 8, the Martens hardness (25°C) was 20 to 300 N / mm². 2 Within the specified range, the higher the Martens hardness, the smaller the relatively adsorption area (adsorption) in the adsorption test (more gaps), and the higher the relatively peelability (lower peeling force) in the peel test. In other words, the lower the Martens hardness, the larger the relatively adsorption area (adsorption) in the adsorption test (less gaps), and the lower the relatively peelability (higher peeling force) in the peel test. That is, to achieve a good balance between adsorption and peelability, the Martens hardness of the retaining layer should be between 150 and 230 N / mm². 2 It can be seen that this is preferable. Furthermore, the Young's modulus of the retaining layer shows a similar trend (Table 1).

[0063] Focusing on Examples 1, 11-12, the mean square surface roughness was 2.1-12.1 nm / μm 2Within the specified range, the larger the mean square surface roughness, the smaller the relatively adsorption area (adsorption) in the adsorption test (more gaps), and the higher the relatively peelability (lower peeling force) in the peel test. In other words, the smaller the mean square surface roughness, the larger the relatively adsorption area (adsorption) in the adsorption test (less gaps), and the lower the relatively peelability (higher peeling force) in the peel test. That is, to achieve a good balance between adsorption and peelability, the mean square surface roughness of the retaining layer should be 2.0 μm. 2 10nm / μm or more 2 It can be seen that the following is preferable.

[0064] Focusing on Examples 9 and 10, which included an adhesion layer, when the Martens hardness (25°C) was in the relationship substrate > retaining layer > adhesion layer (Example 9), the adsorption between the retained object and the retaining layer was better than when the Martens hardness (25°C) was adhesion layer > retaining layer (Example 10). Furthermore, in Example 10, the peelability of the retained object in the peel test was good. This is presumed to be because, in Example 10, the Martens hardness of the adhesion layer is higher than that of the retaining layer, making the retaining layer less prone to deformation.

[0065] Although not included in the evaluation criteria, the inventors also found that the presence of an adhesion layer makes delamination between the substrate, retaining layer, and adhesion layer less likely to occur.

[0066] <<Embodiment 2>> An embodiment of the present disclosure (Embodiment 2), different from the holding member 1 according to the embodiment of the present disclosure described above, will be described below. The holding member according to Embodiment 2 maintains or improves the holding force on the object to be held, and allows the object to be suitably attached to and detached. In the following description and drawings, components that have a reference number that is 100 added to the reference number of the components of the holding member 1 have the same or similar function as the components of the holding member 1, unless otherwise specifically stated (i.e., components whose last two digits of the reference number match have the same or similar function), and detailed explanations will be omitted as appropriate.

[0067] [Holding Member 100] The holding member 100 according to Embodiment 2 comprises a holding layer 110 and a base material 120, and the holding member 1 may further comprise an adhesion layer 130 (Figure 4). In Embodiment 2 as well, the object to be held (object to be held) W is placed on the holding layer 110 and held. This object to be held (object to be held) W is not particularly limited as described above.

[0068] In Embodiment 2, the base material 120 is stretchable. Thus, as shown in Embodiment 1, the retaining force is maintained or improved by the retaining layer 110, and the object to be held W can be attached to and detached from the retaining member 100 (see Figure 5, Example, described later).

[0069] The elongation rate of the base material 120 can be 5 to 450%, with 10 to 350% being preferred. In this way, the holding member 100 can exhibit suitable elongation. The elongation rate can be measured as the value at the time the sample is stretched and broken (see Examples for details).

[0070] The elongation rate of the retaining layer 110 is not particularly limited, but can be set to 1 to 15%. In this case, the extensibility of the retaining member 100 can be more reliably ensured. If an adhesive layer 130 is also provided, the elongation rate of the adhesive layer 130 may also be within this range. The material of the retaining layer 110 may be plastically deformable.

[0071] The elongation rate of the base material 120 is preferably higher than that of the retaining layer 110 (adhesion layer 130). By providing a difference in elongation rates, the object to be retained W can be more effectively attached to and detached from the retaining member 100 (Figure 5).

[0072] Figure 5 is a schematic diagram illustrating an exemplary state when attaching and detaching the object to be held W from the holding member 100. Figures 5(a) to (c) show top views of the holding member 100 holding multiple objects to be held W. The outer edge of the holding member 100 is omitted.

[0073] Figure 5(a) shows the state of the holding member 100 holding the object to be held W before extension, and Figure 5(b) shows the state after the holding member 100 has been extended in the left-right direction of the drawing from the state in (a). By extending the holding member 100, the multiple objects to be held W on the holding member 100 also move away from each other. By adjusting the elongation rates of the holding layer 110 and the base material 120, the distance between the objects to be held W can be adjusted so that they do not come into contact with each other more reliably after extension. Although not shown, by making the elongation rate of the base material 120 higher than that of the holding layer 110, if the base material 120 is continued to be stretched after the holding layer 110 has reached its maximum extension, a partial crack will occur in the holding layer 110, and the objects to be held W can be easily detached from the holding member 100 starting from the crack (i.e., the objects to be held W can be detached from the holding member 100 without requiring any special processing).

[0074] Figure 5(c) shows the state after the holding member 100 has been pushed up from below onto the central object W1 among multiple objects W, when the elongation rate of the base material 120 is higher than the elongation rate of the holding layer 110. Although objects W1 to W3 are all the same member, they are given different reference numerals for explanatory purposes. It is assumed that objects W1 to W3 were aligned in a grid pattern before being pushed up. The area indicated by R shows the area of ​​the holding member 100 that has been raised by being pushed up from below. Figure 5(c) shows the state in which the holding layer 110 near W1 has been stretched as the stacked holding layer 110 and base material 120 in the holding member 100 have been pushed up from below (stretched upward). In other words, Figure 5(c) shows that because the holding layer 110 (holding member 100) in region R has stretched, the object to be held W3, which is located farther from region R than the object to be held W2 that is in contact with region R, is hardly affected by the pushing up effect on the holding layer 110 (it remains in the position before the pushing up). On the other hand, in Figure 5(c), the object to be held W1 can be easily detached from the holding member 100 by pushing up from below, starting from a partial tear that occurs when the holding layer 110 exceeds its maximum elongation (the object to be held W1 can be detached from the holding member 100 without requiring any special processing).

[0075] As shown in the examples described later (Table 2), a higher Martens hardness tends to result in a lower elongation of the component. Therefore, it is preferable that the Martens hardness of the base material 120 is lower than that of the retaining layer 110 (the method for measuring Martens hardness is the same as described above). In Embodiment 2, the Martens hardness of the base material 120 is 10 to 110 N / mm². 2 It can be done this way.

[0076] The material of the base material 120 is not particularly limited as long as it can exhibit the above-described properties. For example, an extendable resin can be used, such as a thermoplastic elastomer, thermosetting elastomer, or photocurable elastomer. Specific examples of thermoplastic elastomers include olefin resins, styrene resins, urethane resins, ester resins, and amide resins. Specific examples of thermosetting elastomers include silicone resins, fluororesins, and urethane resins. Photocurable elastomers include acrylic resins, urethane resins, and styrene resins. Other materials (additives, fillers, etc.) may be added as appropriate depending on the material (properties) of the supporting retaining layer 110.

[0077] The Young's modulus of the base material 120 can be 0.01 to 10 MPa, and preferably 0.1 to 2 MPa. The Young's modulus of the retaining layer 110 can be 0.1 to 5,000 MPa, and preferably 0.1 to 3 MPa. When the Young's moduli of the base material 120 and the retaining layer 110 are within this range, the retaining member 100 can exhibit suitable elongation and can suitably attach and detach the object to be held W.

[0078] (Manufacturing method and application of the retaining member 100) The retaining member 100 can be manufactured as follows, for example. First, a retaining layer 110 and a base material 120 are prepared. The retaining layer 110 and the base material 120 can be brought into close contact, for example by a roll press, via an adhesive layer 30 as needed, to manufacture the retaining member 100.

[0079] The shape, dimensions, etc., of the holding member 100 and the object to be held W are not particularly limited and can be appropriately modified according to the application. The holding member 100 can also be used, similar to Embodiment 1, to hold objects such as wafers in dry etching and CVD processes in semiconductor manufacturing. In particular, when electrostatic force is used in conjunction with plasma-based devices and methods for holding objects, even if the electrostatic force decreases, or if the object to be held is made of a material that does not act on electrostatic force, the holding force of the holding layer 110 (holding member 100) improves under high-temperature conditions due to plasma irradiation, allowing the object placed and pressed on the holding member 100 to be held. Furthermore, as the temperature of the holding layer 110 decreases, the holding force of the holding layer 110 decreases, making it easier to peel the object to be held from the holding layer 110.

[0080] For example, when it is desired to suitably attach and detach the object to be held W from the holding member 100, such as when used as a dicing tape (Figure 5), the thickness of the holding layer 110 is preferably 0.1 μm to 100 μm, the thickness of the base material 120 is preferably 50 μm to 1000 μm, and the ratio of the thickness of the holding layer 110 to the thickness of the base material 120 (thickness of base material 120 / thickness of holding layer 110) is preferably 0.5 to 10000.

[0081] [Holding device] As in Embodiment 1, the present disclosure also provides a holding device comprising a holding member 100 and an adhesion mechanism for bringing the object to be held W into close contact with the holding layer 110. The holding device may further have a detachment mechanism for attaching and detaching the object to be held W held by the holding member 100. In Embodiment 2, an example of the detachment mechanism is a pin that physically pushes up the base material 120. The holding device may also include a tensioning mechanism for stretching the holding member 100 along the planar direction.

[0082] However, the retaining member 100 and retaining device according to this embodiment are not limited to the above-described configurations or combinations.

[0083] Embodiment 2 will be described in more detail below with reference to an example.

[0084] (Examples 13-19) Retaining members were manufactured using materials (retaining layer, base material) having the thickness and characteristics shown in Table 2. The size of the retaining layer and base material was 100 x 100 mm in all cases, and the thickness was as described in Table 2.

[0085] In Examples 13 to 19, thermoplastic polyimide was used as the material for the retaining layer, and it was prepared to achieve the Martens hardness (25°C) shown in Table 2.

[0086] As the base material, acrylic rubber was used in Examples 13-15, silicone rubber in Example 16, polyurethane rubber in Example 17, and silicone rubber in Examples 18 and 19.

[0087] Thickness, Martens hardness, mean square surface roughness, and Young's modulus (25°C, tensile modulus) were measured in the same manner as in the example of Embodiment 1.

[0088] The elongation rates of the retaining layer and substrate of each retaining member were measured as follows.

[0089] [Elongation of the base material] The holding member was cut to obtain strip-shaped test pieces (5.0 mm wide, 30 mm long). The longitudinal ends of the test pieces were gripped with a universal tensile testing machine, and a tensile test was performed at a speed of 1 mm / min. The elongation of the base material was measured from the ratio of the length of the test piece (base material) at the time of fracture to the length of the test piece before measurement. Elongation of the base material (%) = Length of the test piece (base material) at fracture / Length of the test piece (base material) before test × 100

[0090] [Elongation of the Retaining Layer] The retaining member was cut to obtain strip-shaped test pieces (5.0 mm wide, 30 mm long). The longitudinal ends of the test pieces were gripped with a universal tensile testing machine, and a tensile test was performed at a speed of 1 mm / min. The elongation of the retaining layer was measured from the ratio of the length of the test piece (retaining layer) at the time of fracture to the length of the test piece before measurement. Elongation of the retaining layer (%) = Length of the test piece (retaining layer) at fracture / Length of the test piece (retaining layer) before test × 100

[0091] [Evaluation Method] Adsorption and peel tests were performed on each holding member in the same manner as in the embodiment of Embodiment 1. A silicon wafer cut to 25 x 25 mm and 300 μm thick was used as the object to be held.

[0092]

[0093] As shown in Table 2, the Martens hardness of the portion in contact with the object being held is 20 to 300 N / mm². 2 The retaining members (Examples 13-19) comprising a retaining layer and a substrate supporting the retaining layer exhibited good adsorption and release properties. This suggests that the present disclosure can provide new retaining members and retaining devices that maintain or improve the retaining force on the object to be held.

[0094] Furthermore, in Embodiment 2, the Martens hardness (25°C) of the retaining layer is 20 to 300 N / mm². 2 Within the specified range, the lower the Martens hardness, the lower the relative peelability (higher peeling force) in the peel test tended to be (Examples 14, 15, and 17). In Example 14, the retaining layer had a higher elongation rate than the substrate, which is presumed to have contributed to the high peeling force because cracking of the retaining layer was less likely to occur.

[0095] In Examples 13 to 19, both the retaining layer and the substrate tended to exhibit lower elongation as their Martens hardness increased, and higher elongation as their Martens hardness decreased. This suggests that, in order to exhibit the effects shown in Figure 5, the materials of the retaining layer and the substrate can be selected based on their Martens hardness. In Example 19, the balance between the elongation of the retaining layer and the substrate was good, suitable cleavage occurred in the retaining layer, and it is thought that particularly good adsorption and release properties were observed.

[0096] In particular, focusing on Examples 13, 16-19, in which the Martens hardness, elongation, and thickness of the retaining layer were equivalent, it was found that good adsorption and release properties were observed when the elongation of the substrate was in the range of 13-420%. Furthermore, the Martens hardness of the substrate was between 5-50 N / mm². 2 It was found that within the specified range, good adsorption and detachability were observed.

Claims

1. The Martens hardness of the part in contact with the object being held is 20 to 300 N / mm². 2 A retaining member comprising a retaining layer and a base material that supports the retaining layer.

2. The retaining member according to claim 1, comprising an adhesion layer for bringing the retaining layer and the substrate into close contact, wherein the Martens hardness of the substrate, the retaining layer and the adhesion layer are in the relationship: substrate > retaining layer > adhesion layer.

3. The mean square surface roughness of the portion of the holding layer that comes into contact with the object to be held is 10 nm / μm 2 The retaining member according to claim 1 or 2, which is as follows:

4. The retaining member according to any one of claims 1 to 3, wherein the retaining layer has at least one property selected from the group consisting of plasma resistance, chemical resistance, heat resistance, water resistance, and stain resistance.

5. The retaining member according to any one of claims 1 to 4, wherein the retaining layer comprises a polyimide resin, a polyamide resin, or a polyolefin resin.

6. The holding member according to any one of claims 1 to 5, wherein the substrate comprises electrodes.

7. The retaining member according to any one of claims 1 to 6, wherein the base material is stretchable.

8. The retaining member according to claim 7, wherein the elongation rate of the retaining layer is 1 to 15%.

9. The retaining member according to claim 7, wherein the elongation rate of the base material is 5 to 450%.

10. The Martens hardness of the substrate is 10 to 110 N / mm². 2 The retaining member according to claim 7.

11. A holding device comprising a holding member according to any one of claims 1 to 10, and an adhesion mechanism for bringing an object to be held into close contact with the holding layer.

12. The holding device according to claim 11, further comprising a detachment mechanism for attaching and detaching an object to be held by the holding member.

Images