JPWO2014129480A1 - Temporary bonding resin, temporary bonding resin layer, hard substrate with temporary bonding resin layer, thin film substrate laminate, and thin film substrate processing process - Google Patents

Abstract

In the processing of thin film substrates used for components and displays in electronic devices, even in heat treatment, the thin film substrate can be fixed and transported accurately and processed without displacement, and decomposed and generated gas (outgas) To provide a temporary adhesion resin layer that does not affect the vacuum apparatus due to contaminants such as, and that does not see the penetration of strong acid or polar solvent during patterning and can maintain good adhesion. Temporary adhesion resin for temporarily adhering the thin film substrate to a hard substrate serving as a base when processing the thin film substrate, comprising at least one fluororesin, And a temporary adhesion resin layer formed from the temporary adhesion resin.

Description

  The present invention relates to a temporary bonding resin, a temporary bonding resin layer, a hard substrate with a temporary bonding resin layer, a thin film substrate laminate, and a thin film substrate processing process. More specifically, when processing the thin film substrate, at least the temporary adhesion resin and the temporary adhesion resin layer for temporarily adhering the thin film substrate to the rigid substrate serving as the pedestal, and at least the rigid substrate serving as the tentative adhesion resin layer. The present invention relates to a hard substrate with a temporary adhesion resin layer provided on one side, a thin film substrate laminate in which a thin film substrate and a pedestal hard substrate are joined via a temporary adhesion resin layer. The present invention also relates to a thin film substrate processing process in which the thin film substrate is processed using the temporary adhesion resin layer.

  Conventionally, substrates such as silicon substrates for semiconductor wafers, sapphire substrates and SiC substrates used for LEDs, metal films, TFT substrates using glass substrates for displays, color filter substrates, base substrates for organic EL panels, etc. It has rigidity because of its thickness, and it does not have to worry about handling such as fixing and moving in processes such as pattern formation on the substrate, heat treatment such as CVD, sputtering, and treatment process with chemicals. It was possible to carry out pattern formation on these substrates while being fixed at an accurate position.

  However, in recent years, components and displays in electronic devices, more specifically, in the semiconductor field, compound semiconductor substrates that serve as substrates, silicon substrates that serve as MEMS devices, passive matrix substrates, and cover glasses used on the surfaces of smartphones Or a front cover glass using an OGS (One Glass solution) substrate with a touch panel sensor attached thereto, or an organic or organic-inorganic hybrid substrate based on silsesquioxane, and more recently called a flexible display. There are active studies to manufacture the above TFT, passive matrix, and color filter substrates using glass substrates or various engineering plastics and super engineering plastics. Development of a type characterized by its volume and thinness has been started.

  It is difficult to directly handle such a light, thin, and non-rigid thin film substrate as in the conventional method for processing and pattern formation. In particular, when pattern formation is performed, there is a problem in that the position is shifted due to slight distortion of the substrate, resulting in a significant decrease in yield. Therefore, recently, various kinds of glass substrates such as quartz, soda lime, tempered glass, etc., silicon substrates and sapphire substrates used in semiconductors, compound semiconductor substrates, or various metal substrates including stainless steel, high tension, etc. A thin film substrate is temporarily fixed via a resin material for fixing, and processed and transported.

  For example, it is known that a double-sided adhesive tape is bonded between a semiconductor wafer serving as a thin film substrate and a supporting wafer serving as a pedestal, and handling including transportation is performed (see Patent Documents 1 to 3). In particular, it is disclosed that a thermal expansion type adhesive or an ultraviolet photosensitive adhesive is used as a double-sided pressure-sensitive adhesive sheet in consideration of peeling after the treatment process. When using such a thermal expansion-type pressure-sensitive adhesive, the adhesive force can be reduced by heat treatment, and when using an ultraviolet photosensitive adhesive, the adhesive force can be reduced by ultraviolet irradiation, and after processing There was an advantage that the semiconductor wafer could be easily peeled off. However, when the thin film substrate is processed under vacuum conditions such as sputtering and CVD, the gas in the microcapsule contained in the thermal expansion adhesive is released, and the adhesive force is reduced during processing, or the vacuum chamber is It was contaminated and the device had to be cleaned again, which could reduce the operating rate. Further, there is a problem that the treatment cannot be performed at a temperature higher than that at the time of heat peeling, or that a residue of 0.5 to 10 μm size derived from the adhesive adheres to the adherend when peeling. On the other hand, in the case of an ultraviolet photosensitive adhesive, a photopolymerization initiator is usually added. However, in an environment treated at a high temperature of 100 ° C. or higher, it decomposes by heat, and thus reacts during the heating process. Therefore, there is a problem that the adhesive strength does not decrease even if ultraviolet irradiation is performed thereafter, and further improvement has been demanded.

  Furthermore, when patterning on various substrates, not only a weak acid such as acetic acid but also a strong acid treatment such as hydrofluoric acid and oxalic acid is required for unnecessary sputtering film etching. Furthermore, in the LED process or the like, depending on the user, application and cleaning are often performed using a polar solvent such as N-methylpyrrolidone or acetone, and the end face of the temporary bonding resin comes into contact with these chemical solutions. In this case, the double-sided pressure-sensitive adhesive tape is barely damaged under extremely short conditions such as within 30 seconds at room temperature, but under these conditions, the chemical solution penetrates from the pressure-sensitive adhesive, contaminates the back surface, or is a substrate in the middle of handling. Sometimes dropped.

JP 2005-116948 A JP 2010-56562 A JP-A-6-216092

  The present invention has a problem with the above-described conventional technology, that is, in the processing of a thin film substrate used for components or displays in electronic devices, the thin film substrate is accurately fixed and transported even in heat treatment, and the position is shifted. It can be processed without contamination, and it does not affect the vacuum device due to contaminants such as decomposition and generated gas (outgas). Furthermore, no strong acid or polar solvent enters during patterning and maintains good adhesion. It is to provide a resin for temporary bonding that is possible. It is another object of the present invention to provide a temporary bonding resin that can be peeled lightly and without contamination when peeling.

  As a result of intensive studies to achieve the above object, the present inventors have found that the above object can be achieved by using a fluororesin as the temporary adhesion resin layer, and the present invention has been completed.

  That is, the present invention is a temporary bonding resin that temporarily bonds the thin film substrate to a hard substrate that serves as a base when the thin film substrate is processed, and includes at least one fluororesin. A temporary bonding resin is provided.

  In one embodiment, at least polytetrafluoroethylene is included as the fluororesin.

  Moreover, this invention provides the resin layer for temporary adhesion formed from the said resin for temporary adhesion.

  In one embodiment, the temporary adhesion resin layer of the present invention has a thermal decomposition rate when the temperature is raised from room temperature to 200 ° C. under conditions of a temperature rising rate of 10 ° C./min and a flow rate of 200 ml / min. Is 1 wt% or less.

  In one embodiment, the resin layer for temporary adhesion is a porous membrane. In one embodiment, the resin layer for temporary adhesion is unfired. In one embodiment, the temporary adhesion resin layer is stretched.

  The present invention is also a hard substrate with a temporary adhesion resin layer for temporarily bonding the thin film substrate when processing the thin film substrate, the hard substrate serving as a pedestal, and provided on at least one surface of the hard substrate. Also provided is a hard substrate with a temporary adhesion resin layer having the temporary adhesion resin layer. In one embodiment, the hard substrate serving as the pedestal is selected from a glass substrate, a silicon substrate, and a sapphire substrate.

  The present invention also provides a thin film substrate laminate formed by bonding a thin film substrate and a hard substrate serving as a base with the resin layer for temporary bonding. In one embodiment, the hard substrate serving as the pedestal is any one selected from a glass substrate, a silicon substrate, and a sapphire substrate.

Furthermore, the present invention is a thin film substrate processing process for processing a thin film substrate,
A step (1) of joining the thin film hard substrate and a hard substrate to be a pedestal by the temporary adhesive resin layer;
Step (2) of performing heat treatment and / or chemical treatment
And a step (3) of peeling the thin film substrate,
A thin film substrate processing process is provided.

  In one embodiment, the chemical solution used in the chemical treatment step is hydrofluoric acid, oxalic acid, acetone, N-methyl-2-pyrrolidone (NMP), dimethyl sulfoxide (DMSO), toluene, potassium hydroxide aqueous solution ( KOH), tetramethylammonium hydroxide aqueous solution (TMAH), diethylene glycol monobutyl ether (BGD), monoethanolamine (MEA), aluminum acid, and isopropyl alcohol.

  The temporary adhesion resin layer formed from the temporary adhesion resin of the present invention is used for a process and / or a chemical immersion process in which a thin film substrate is fixed and transported accurately and performed under heating conditions (including heating under vacuum). Even if it is passed, the product thin film substrate can be firmly fixed without dropping off, there is no problem of outgas, etc., and there is no contamination in the device, and light peeling and contamination are seen in the peeling process after processing Therefore, extremely high production yields can be achieved.

FIG. 1 is a schematic cross-sectional view showing an example of a hard substrate with a resin layer for temporary bonding according to the present invention. FIG. 2 is a schematic top view showing an example of a hard substrate with a resin layer for temporary bonding according to the present invention. FIG. 3 is a schematic cross-sectional view showing an example of the thin film substrate laminate of the present invention. FIG. 4 is a schematic process diagram showing an example of the thin film substrate processing process of the present invention. FIG. 5 is a schematic diagram showing a method for evaluating heat resistance in an example of the present invention.

Hereinafter, embodiments of the present invention will be described in detail.

(Temporary bonding resin)
The temporary bonding resin of the present invention is characterized by containing at least one fluororesin. The temporary bonding resin of the present invention can be used when temporarily bonding a thin film substrate to a hard substrate serving as a base when processing the thin film substrate.

  The fluororesin is optimal as the temporary bonding resin of the present invention because it is excellent in heat resistance, chemical resistance, electrical characteristics, etc., and has little outgas. In the present invention, for example, polytetrafluoroethylene (PTFE), which is a fully fluorinated resin, is preferably used as the fluororesin, but in addition, polychlorotrifluoroethylene (PCTFE), polyvinylidene fluoride (PVDF), polyfluoride Partially fluorinated resins such as vinyl (PVF), perfluoroalkoxy fluororesin (PFA), tetrafluoroethylene / hexafluoropropylene copolymer (FEP), ethylene / tetrafluoroethylene copolymer (ETFE), ethylene A fluorinated resin copolymer such as chlorotrifluoroethylene copolymer (ECTFE), a fluorinated acrylic resin, a fluororubber, or the like can be used. Polytetrafluoroethylene (PTFE) can be used up to the highest temperature among fluororesins, and has an extremely high melt viscosity even when used at a temperature exceeding the melting point. Therefore, when a temporary adhesion resin layer (described later) is formed using PTFE, there is an advantage that the shape of the resin layer can be maintained. In the temporary bonding resin of the present invention, these fluororesins can be used alone or in combination of two or more.

  In the temporary bonding resin of the present invention, a fluororesin having a compressive strength (ASTM D695, 1% deformation, 25 ° C.) of 3 MPa to 14 MPa, more preferably 4 MPa to 10 MPa is preferably used. If a fluororesin in such a range is used, a deformable temporary adhesion resin layer (described later) can be formed. Such a temporary adhesion resin layer has high adhesion at the time of adhesion and a wide contact area, and thus exhibits excellent adhesion.

  When PTFE is used as the fluororesin, the form of the PTFE raw material may be any of molding powder, fine powder, and dispersion, but from the viewpoint of forming a temporary adhesion resin layer having excellent unevenness followability, It is preferable to use molding powder or fine powder, and fine powder is particularly preferable from the viewpoint of workability described later.

  In the present specification, “temporary bonding resin” is a concept including the meaning of the temporary bonding resin composition. That is, the temporary adhesion resin of the present invention may be composed of only a fluororesin, but may further contain other components as long as the effects of the present invention are not impaired. Examples of other components include liquid lubricants, dispersants (surfactants), glass beads, balloons, fillers, pigments, solvents, and the like. When the temporary bonding resin contains the other components, the content ratio of the fluororesin to the total amount of the temporary bonding resin (total amount of the resin and other components) is preferably 5% by mass to 95% by mass. More preferably, it is 10 mass%-90 mass%. On the other hand, when the temporary bonding resin contains a fluororesin as a main component (that is, when a temporary bonding resin that does not include the other components is used), the content of the fluororesin with respect to the total amount of the temporary bonding resin is 50 masses. % Or more, more preferably 60% by mass or more, still more preferably 70% by mass or more, and particularly preferably 80% by mass or more.

  The liquid lubricant is used when a fluororesin is paste-extruded to be described later to form a temporary adhesion resin layer. Further, the dispersant is blended when the fluorine tree is dispersed in the solvent. For example, the dispersant is a fluorine-based compound such as perfluoroalkyl sulfonate, perfluoroalkyl carboxylate, and perfluoroalkyl quaternary ammonium salt. Silicone surfactants such as surfactants, polyether-modified silicone oils, and alcohol-modified silicone oils are used. Specifically, commercially available products such as silicone surfactant “L-77” manufactured by Nihon Unicar Co., Ltd. and nonionic surfactant “Triton X-100” manufactured by Roche Applied Science Co., Ltd. can be used. The solvent is a medium in which the fluororesin is dispersed, and examples thereof include polar solvents such as water, alcohols, dimethylacetamide (DMAC) and dimethylformamide (DMF).

(Resin layer for temporary bonding)
In the present invention, the temporary bonding resin layer is formed from the temporary bonding resin. That is, the temporary adhesion resin layer of the present invention may be formed only of the fluororesin, and may further contain other components in addition to the fluororesin. The production method is not particularly limited, and examples thereof include a method of extruding a temporary bonding resin, a method of spray-coating a temporary adhesive resin dispersion, and the like.

  In the present invention, the temporary adhesion resin layer is preferably a porous film. Moreover, it is preferable that it is unfired (that is, it does not pass through a heat history higher than the melting point in the processing process). Moreover, it is preferable that the extending | stretching process is carried out. In particular, an unfired PTFE porous membrane is preferably used. This is usually produced by a stretching method. A long PTFE porous membrane obtained by a method other than the stretching method can also be used.

  A specific example of the stretching treatment when PTFE is used as the fluororesin will be shown. In addition, when extending | stretching fluororesins other than PTFE, it can handle similarly. First, a paste-like mixture obtained by adding a liquid lubricant to PTFE fine powder is preformed. PTFE fine powder is suitable as a PTFE raw material because of the ease of paste extrusion. The liquid lubricant is not particularly limited as long as it can wet the surface of the PTFE fine powder and can be removed by extraction or heating. For example, hydrocarbons such as liquid paraffin, naphtha, and white oil can be used. . The addition amount of the liquid lubricant is suitably about 5 to 50 parts by mass with respect to 100 parts by mass of the PTFE fine powder. The preforming is performed at a pressure that does not squeeze out the liquid lubricant.

  Next, this preformed body is preferably paste extruded to form a molded body. The shape of the molded body is not particularly limited as long as it can be stretched, and may be, for example, a tape, a sheet, a tube, or the like. The size of the molded body is preferably set so that the PTFE porous membrane has a desired thickness by stretching described later. Moreover, it is good to remove a liquid lubricant suitably by a conventional method in the stage used as a molded object. In the present invention, the unstretched fluororesin layer thus obtained can be used as a temporary adhesive resin layer.

  This molded body is stretched in at least a uniaxial direction to obtain a PTFE porous membrane. The draw ratio is not particularly specified, but the draw ratio is preferably 2 to 15 times and more preferably 5 to 10 times in consideration of stretching unevenness and breakage during stretching. The stretching temperature is not particularly specified, and is generally less than the melting point (327 ° C.) of PTFE (usually 150 ° C. to 300 ° C.). Moreover, after extending | stretching to a uniaxial direction, you may extend | stretch with respect to a perpendicular direction (namely, biaxial stretching). As for the stretching conditions in the case of performing biaxial stretching, the area stretching ratio (integration of the stretching ratio in the uniaxial direction and the stretching ratio in the direction perpendicular thereto) is preferably 50 times to 900 times, and preferably 100 times to 300 times. It is more preferable.

  In the PTFE porous membrane suitable for the present invention, the above-mentioned stretching is usually performed at a temperature of 240 ° C. to 300 ° C., preferably 270 ° C. to 290 ° C., usually 2 times to 15 times, preferably 5 times to 10 times. It can be obtained by uniaxial stretching (longitudinal stretching) at a magnification.

  When it is desired to improve strength, improve dimensional stability, etc., the porous membrane is heated at a temperature equal to or higher than the melting point of the fluororesin (usually 330 ° C. to 500 ° C.), usually 60 seconds or less, and then fired. . The stretching temperature may be set to a temperature equal to or higher than the melting point of the fluororesin and fired while stretching. In the present invention, the temporary adhesion resin layer may be a fired product or an unfired product, but an unfired product is preferable from the viewpoint of adhesiveness.

The temporary adhesive resin layer of the present invention is preferably a porous film. By using the porous film, there is an advantage that the resin can be easily deformed at the time of attachment and sufficient adhesion can be easily obtained. The porosity of the porous membrane is not particularly limited, but is usually preferably 50% to 90%, more preferably 60% to 85%, and even more preferably 65% to 80%. If the porosity is less than 50%, it may be difficult to deform at the time of pasting, and sufficient adhesion may not be obtained. If the porosity exceeds 90%, it is difficult to control the pasting conditions, and if it is not suitable, liquid penetration will occur. May be more likely to occur. The porosity of the porous film is {1- (weight [g] / (thickness [cm] × area [cm ² ] × true density of fluororesin [g / cm ³ ]))} × 100 (%) It can be obtained from the following formula. The true density of the PTFE resin is 2.18 [g / cm ³ ].

  In the present invention, the temporary adhesion resin layer can be obtained from a dispersion of fluororesin. Specifically, there is a method in which a fluororesin is dispersed in water or alcohol, applied by spray coating or an appropriate coating method, and heated and dried as necessary to form a temporary adhesion resin layer. When the temporary adhesive resin layer is obtained by applying and applying the temporary adhesive resin, a heat treatment or a pressure treatment may be added to improve the strength.

  In the present invention, the resin layer for temporary bonding can also be formed by applying a powder of a fluororesin (fine powder) as a powder without dispersing it in a solvent, followed by heating and pressure treatment.

  The resin layer for temporary bonding according to the present invention is characterized by comprising a fluororesin layer containing at least one fluororesin, but may be composed of only a single fluororesin layer, or a plurality The fluororesin layer may be laminated. Furthermore, as long as the effects of the present invention are not impaired, a resin layer made of a resin other than the fluororesin may be included.

  In the present invention, the thickness of the temporary adhesive resin layer is preferably 0.01 μm to 20 mm, more preferably 0.02 μm to 10 mm, still more preferably 0.03 μm to 2 mm, and particularly preferably 0.03 μm. ~ 1 mm. If the thickness is less than 0.01 μm, it is difficult to form a uniform film. If the thickness is more than 20 mm, the cost as a material increases, which is not preferable.

  The temporary adhesive resin layer of the present invention may be in the form of a sheet, film, or tape, or may be stamped or cut into any shape. In particular, when processing into a tape shape, it may be wound as a roll. Moreover, the resin layer for temporary adhesion of this invention may be formed by applying a resin composition containing a fluororesin.

  The resin layer for temporary bonding of the present invention has a thermal decomposition rate of 1 wt% or less when the temperature is raised from room temperature to 200 ° C. under conditions of a temperature rising rate of 10 ° C./min and an air atmosphere at a flow rate of 200 ml / min. Is preferred. If the thermal decomposition rate is 1 wt% or less, even when the temporary adhesion resin layer is exposed to a high temperature (for example, when used at a high temperature during processing of a thin film substrate), Contaminants such as decomposition products and generated gas (outgas) are reduced. Such a temporary adhesion resin layer can prevent a processing apparatus (for example, a vacuum apparatus) from being adversely affected.

  Furthermore, when laminating a plurality of sheet-like or film-like temporary adhesion resin layers, or when winding a tape-like temporary adhesion resin layer, the temporary adhesion resin layers are self-adhering by direct contact with each other. There is. In order to prevent this, a support can be interposed between the temporary adhesion resin layers. By interposing such a support, excessive deformation of the PTFE porous membrane can be prevented.

  As the material for the support, resin and / or paper are preferable. Therefore, as the support, a resin film, paper, and a composite film in which resin is coated on at least one side of paper can be suitably used. Examples of the resin film include a polyester film, a polypropylene film, and a polyethylene film. Examples of paper include art paper and coated paper. As an example of the composite film, there is a paper in which the resin component of the resin film is coated. The support is particularly preferably a polyester film because it has an appropriate strength, high thickness accuracy, and high peelability of the PTFE porous membrane.

  As thickness of a support body, 15 micrometers-50 micrometers are preferable, and 25 micrometers-38 micrometers are more preferable.

(Thin film substrate)
Any appropriate substrate can be used as the thin film substrate. In the present invention, the substrate used as a thin film substrate is a substrate composed of at least one layer. In the semiconductor field, a silicon or a compound semiconductor substrate, a sapphire substrate or an SiC substrate in an LED, or a MEMS device is used. Glass used on the surface of TFT substrates, passive matrix substrates, color filter substrates, organic EL panel base substrates, smartphones, etc. using glass substrates such as silicon substrates, crystal substrates, soda lime and tempered glass in the display field Various plastic materials called substrates and glass substitute films, front cover glasses using organic or organic / inorganic hybrid substrates based on silsesquioxane, OGS substrates with touch panel sensors attached to them, and more recently flexible There is no limitation be any one of a glass substrate or various engineering plastics and super engineering plastic substrate or a metal thin film called stable display. Especially in the flexible display field, polyimide, polycarbonate, polyethersulfone, polyacrylate, polyamide, polynorbornene, polyethylene terephthalate, polyethylene naphthalate, polyetheretherketone, polyamideimide, polyetherimide, polyaramid, polyphenylene sulfide, stainless steel foil, FRP The glass fiber substrate etc. which were included can be used.

  The thin film substrate in the present invention may be not only a single layer but also a multilayer or multilayer, and a treatment layer may be provided on any surface for improving wear resistance and smoothness.

  The surface roughness of the thin film substrate is not particularly limited, but the surface to which the temporary adhesion resin layer is bonded is preferably relatively smooth. In this respect, Rmax is preferably less than 100 μm, and less than 80 μm. Is more preferable, and it is still more preferable that it is less than 50 micrometers.

  The thickness of the thin film substrate is preferably 5 μm to 10 mm, more preferably 10 μm to 5 mm, and even more preferably 20 μm to 1 mm. If it is such a range, a lightweight and thin film will be attained, and final assembly will become easy.

(Rigid board that serves as a base)
Any appropriate substrate can be used as the hard substrate. As the hard substrate used in the present invention, various glass substrates such as soda lime and tempered glass; silicon substrates or sapphire substrates used in semiconductors; compound semiconductor substrates; stainless steel, high tension, etc. may be used. It is preferably any one selected from a glass substrate, a silicon substrate, and a sapphire substrate. In the present invention, it is preferable that the linear expansion coefficients of the hard substrate serving as a pedestal and the thin film substrate serving as a target are from room temperature to 120 ° C., preferably from 200 ° C. By matching the linear expansion coefficients of the hard substrate serving as the pedestal and the thin film substrate, it becomes possible to control warping, bending, and the like during conveyance.

  The rigid substrate may be provided with a pattern or a fine hole for assisting the transportability / peelability as long as the rigidity capable of holding the original intended thin film substrate can be maintained.

  The thickness of the hard substrate is preferably 0.01 mm to 15 mm, more preferably 0.02 mm to 10 mm, and even more preferably 0.03 mm to 7 mm. If the thickness of the hard substrate is 0.01 mm to 15 mm, it is preferable in that it is easy to hold and transport and has impact resistance. If the thickness satisfies the holding / impact resistance, the thinner one is also preferable in this thickness range, because it is lighter and easier to transport.

(Hard substrate with resin layer for temporary bonding)
The hard board | substrate with the resin layer for temporary adhesion of this invention is demonstrated with reference to drawings. FIG. 1 is a schematic sectional view showing an example of the hard substrate 3 with a temporary adhesion resin layer of the present invention. The hard substrate 3 with a temporary adhesion resin layer includes a hard substrate 2 serving as a pedestal and a temporary adhesion resin layer 1 provided on at least one side of the hard substrate 2. The details of the temporary adhesion resin layer 1 are as described above. The hard substrate with a temporary adhesion resin layer of the present invention can be used when processing a thin film substrate.

  FIG. 2 is a schematic top view illustrating an example of the hard substrate 3 with a temporary adhesion resin layer according to the present invention, and four temporary adhesion resin layers 1 are provided on the upper surface of the hard substrate 2 serving as a pedestal. The shape of the hard substrate 2 is not particularly limited, and may be a square or a rectangle, and may be processed into an arbitrary shape. Although the size is not particularly limited, for example, when the shape is substantially rectangular, the vertical length is 10 mm to 3010 mm, and the horizontal length is about 10 mm to 3010 mm. When the shape is substantially circular, the diameter is about 10 mm to 450 mm.

  Further, the shape of the temporary adhesion resin layer 1 provided on the hard substrate 2 is not particularly limited, and may be a square or a rectangle, and may be processed into an arbitrary shape. Although the size is not particularly limited, for example, when the shape is substantially rectangular, the vertical length is 10 mm to 3010 mm, and the horizontal length is about 10 mm to 3010 mm. When the shape is substantially circular, the diameter is about 10 mm to 450 mm.

  Further, the number (number) of the temporary adhesion resin layers 1 provided on the hard substrate 2 is not particularly limited, and may be one or a plurality. The size of the temporary adhesion resin layer 1 with respect to the hard substrate 2 and the thin film substrate 4 to be described later is not particularly limited, but is preferably equal to or smaller than that of the hard substrate 2. Are preferably equal or larger. When the temporary adhesion resin layer 1 is smaller than the thin film substrate 4, the thin film substrate 4 may not be sufficiently fixed. On the other hand, when the temporary adhesion resin layer 1 is larger than the thin film substrate 4, a sufficient adhesive force can be obtained, and when the thin film substrate 4 is peeled off, the temporary adhesion resin layer can be lifted from the end more easily and easily. The thin film substrate 4 can be peeled off without being damaged.

  In order to provide the temporary adhesion resin layer 1 on the hard substrate 2, the previously prepared temporary adhesion resin layer 1 may be attached to the hard substrate 2, or the temporary adhesion resin or temporary adhesion resin may be applied to the hard substrate 2. The resin layer 1 for temporary adhesion may be formed by applying a resin composition. The method of pasting the temporary adhesion resin layer 1 on the hard substrate 2 may be a method of pasting at room temperature, a method of pasting by heating, or pasting by pressurization or reduced pressure (for example, vacuum). It may be attached.

(Thin film substrate laminate)
The thin film substrate laminate of the present invention will be described with reference to the drawings. FIG. 3 is a schematic cross-sectional view showing an example of the thin film substrate laminate 5. The thin film substrate laminate 5 is formed by bonding a thin film substrate 4 and a hard substrate 2 serving as a pedestal with a temporary adhesion resin layer 1. In other words, in the thin film substrate laminate 5, the temporary adhesion resin layer 1 is provided on one surface of the hard substrate 2 serving as a pedestal, and the thin film substrate 4 is further provided. The details of the thin film substrate 4, the hard substrate 2, and the temporary adhesion resin layer 5 are as described above.

  The shape of the thin film substrate 4 is not particularly limited, and may be a square or a rectangle, and may be processed into an arbitrary shape. Although the size is not particularly limited, for example, when the shape is substantially rectangular, the vertical length is 10 mm to 3010 mm, and the horizontal length is about 10 mm to 3010 mm. In FIG. 3, the temporary adhesion resin layer 1 and the thin film substrate 4 are described as having substantially the same shape, but the temporary adhesion resin layer 1 may be set smaller than the thin film substrate 4. Although the temporary adhesion resin layer 1 may be set larger than the thin film substrate 4, it is preferable that the temporary adhesion resin layer 1 is equal to or larger than the thin film substrate 4 as described above.

(Thin film substrate processing process)
The thin film substrate processing process of the present invention is a thin film substrate processing process for processing a thin film substrate, and at least the thin film hard substrate and a hard substrate serving as a pedestal are joined by the temporary adhesion resin layer. Step (1),
Step (2) of performing heat treatment and / or chemical treatment
And a step (3) of peeling the thin film substrate,
It is characterized by including.

The thin film substrate processing process of the present invention will be described with reference to the drawings. FIG. 4 is a schematic process diagram showing an example of a thin film substrate processing process. In this example, first, as shown in FIG. 4A, a hard substrate 3 with a temporary adhesion resin layer and a thin film substrate 4 are prepared. Thereafter, as shown in FIG. 4 (b), the thin film substrate is laminated by attaching and bonding the thin film substrate 4 to the temporary adhesion resin layer 1 provided on one surface of the hard substrate 3 with the temporary adhesion resin layer. The body 5 is produced (step 1). The conditions for attaching the thin film substrate 4 to the temporary adhesion resin layer 1 are not particularly limited, but the temperature is from room temperature to 100 ° C., the pressure is 0.001 to 100 MPa, or the autoclave treatment (0.1 to 10 kg / cm ^2). ) Or 0.1-1 × 10 ⁻⁸ Pa under reduced pressure and vacuum. The attaching method is not particularly limited. For example, it may be bonded by roller bonding, or after being bonded together, the air remaining inside may be extruded toward the outer peripheral portion of the substrate, and becomes a pedestal. You may affix, making a hard board | substrate bend.

  Subsequently, the thin film substrate 4 fixed by the temporary adhesion resin layer 1 provided on one surface of the temporary adhesion resin layer-equipped hard substrate 3 is subjected to heat treatment and / or chemical treatment (step 2). By this heat treatment and / or chemical treatment, as shown in FIG. 4C, a surface treatment layer 6 is formed on the surface of the thin film substrate 4 (the surface opposite to the surface bonded to the temporary adhesion resin layer 1). obtain.

The heat treatment is, for example, a process of forming a circuit pattern or forming a metal layer for heat dissipation on the surface of the thin film substrate 4. The temperature of the heat treatment is usually 110 ° C. or higher. In one embodiment, it is preferable that the temperature of heat processing is 110 to 350 degreeC, and it is more preferable that it is 120 to 350 degreeC. If it is such a range, a device or member with a higher characteristic can be formed. The heating method may be a uniform heating like an oven or a spot heating like a laser. In addition, a xenon lamp or the like is also commonly used. In addition, when forming a metal thin film etc., sputtering, CVD, etc. are often used. The heat treatment may be performed under vacuum conditions, and the degree of vacuum is, for example, about 0.1 Pa to 1 × 10 ⁻⁸ Pa, and may be about 0.05 Pa to 1 × 10 ⁻⁵ Pa. .

  The chemical treatment is, for example, a treatment for leveling and cleaning the circuit pattern layer of the thin film substrate 4 and dissolving or peeling off unnecessary portions for forming a resist / insulating layer for forming a circuit. The chemical solution used for the chemical treatment is not particularly limited as long as it is a commonly used chemical solution and organic solvent. Specifically, hydrofluoric acid, oxalic acid, acetone, N-methyl-2-pyrrolidone (NMP), dimethyl sulfoxide (DMSO), toluene, potassium hydroxide aqueous solution (KOH), tetramethylammonium hydroxide aqueous solution (TMAH), Diethylene glycol monobutyl ether (BGD), monoethanolamine (MEA), aluminum acid, isopropyl alcohol and the like are preferably used. Moreover, these processing temperatures are room temperature-100 degreeC, and processing time is about 10 second-4 hours.

  As the treatment in the step (2), any appropriate treatment other than the heat treatment and the chemical solution treatment may be selected. For example, processing such as thin film processing or vacuum processing may be performed.

  As shown in FIG. 4D, the thin film substrate 4 on which the surface treatment layer 6 is formed is peeled off from the hard substrate 3 with a temporary adhesion resin layer (step 3). At this time, it can be peeled off without applying an external stimulus such as heating or ultraviolet irradiation.

  In the thin film substrate processing process of the present invention, the temporary adhesive resin layer containing at least one fluororesin is used as the temporary adhesive resin layer, so that the thin film substrate can be accurately fixed and transported under heating conditions (vacuum) The thin film substrate that is the product can be firmly fixed without dropping, and there is no problem of outgas and the like, and no contamination occurs in the device. Furthermore, since light peeling and contamination are not observed in the peeling process after the treatment, it is possible to achieve an extremely high production yield.

  Hereinafter, examples and the like specifically showing the configuration and effects of the present invention will be described, but the present invention is not limited to these.

Example 1
PTFE fine powder (trade name “Polyflon PTFE F-104”, compressive strength (ASTM D695, 1% deformation, 25 ° C.) 5 to 6 MPa, manufactured by Daikin Industries, Ltd.) 100 parts by weight, n-dodecane as a liquid lubricant A PTFE unstretched sheet was prepared by paste extrusion using a PTFE composition containing 20 parts by weight of PTFE. Next, the obtained sheet-like mixture was rolled to a thickness of 0.51 mm through a pair of metal rolls, and the molding aid was dried and removed by heating at 150 ° C. to obtain a PTFE sheet molded body. The thickness of the obtained PTFE sheet molded body was 0.50 mm.

(Example 2)
PTFE fine powder (trade name “Polyflon PTFE F-104”, compressive strength (ASTM D695, 1% deformation, 25 ° C.) 5 to 6 MPa, manufactured by Daikin Industries, Ltd.) 100 parts by weight, n-dodecane as a liquid lubricant A PTFE unstretched sheet was prepared by paste extrusion using a PTFE composition containing 20 parts by weight of PTFE. Next, the obtained sheet-like mixture was rolled to a thickness of 0.20 mm through a pair of metal rolls, and the molding aid was dried and removed by heating at 150 ° C. to obtain a PTFE sheet compact. The sheet was longitudinally stretched 5 times at 280 ° C. to produce a uniaxially stretched PTFE porous membrane. The obtained PTFE porous membrane had a thickness of 130 μm and a porosity of 70%.

(Example 3)
PTFE fine powder (trade name “Polyflon PTFE F-104”, compressive strength (ASTM D695, 1% deformation, 25 ° C.) 5 to 6 MPa, manufactured by Daikin Industries, Ltd.) 100 parts by weight, n-dodecane as a liquid lubricant A PTFE unstretched sheet was prepared by paste extrusion using a PTFE composition containing 20 parts by weight of PTFE. Next, the obtained sheet-like mixture was rolled to a thickness of 0.20 mm through a pair of metal rolls, and the molding aid was dried and removed by heating at 150 ° C. to obtain a PTFE sheet compact. This sheet was longitudinally stretched 20 times at 260 ° C. and then transversely stretched 30 times at 150 ° C. to prepare a biaxially stretched PTFE porous membrane. The obtained PTFE porous membrane had a thickness of 10 μm and a porosity of 88%.

(Comparative Example 1)
A double-sided tape in which a silicone pressure-sensitive adhesive layer was bonded to one side of a heat-peelable double-sided pressure-sensitive adhesive sheet (trade name “Riva Alpha No. 31950E”, 200 ° C. foam type, manufactured by Nitto Denko Corporation) was produced.

  In addition, the evaluation item in an Example etc. measured as follows. The results are shown in Table 1.

<Porosity>
The porosity of the PTFE porous membrane, the true density of the PTFE resin as 2.18g / cm ^3, {1- (weight [g] / (thickness [cm] × area [cm ^2] × true density [2. 18 g / cm ³ ]))} × 100 (%).

<Heat resistance evaluation>
The temporary adhesion resin layer prepared in the example was applied as a hard substrate to “MICRO SLIDE GLASS S200034” (size 65 mm × 165 mm, thickness 1.2 mm) manufactured by Matsunami Glass Co., Ltd. on the entire surface with a 2 kg hand roller under 10 reciprocating conditions. I did. Separately, a glass piece obtained by cutting the glass into 40 mm × 120 mm was used as a thin film substrate, and pasted on the opposite surface of the temporary adhesion resin layer with a 2 kg hand roller under 10 reciprocating conditions. This was prepared as an evaluation sample of 50 sheets (see the top view of FIG. 5). Similarly, the double-sided tape of Comparative Example 1 was bonded to glass, but the foamed adhesive surface was the thin film substrate side. After standing on a stand and leaving it at an angle of 45 degrees (see side view in FIG. 5), it is put into a dryer at 180 ° C. for 2 hours, and the floating area between the thin film substrate and the temporary adhesive resin after taking out is set. confirmed. The thing which floated 10% or more with respect to the whole area of a thin film substrate was determined to be unacceptable, and the acceptance rate in all samples was evaluated.

<Contamination evaluation>
By pulling the adhered adhesive resin on the evaluation sample after the heat resistance evaluation, a slight float was generated between the temporary adhesive resin and the edge portion of the thin film substrate. Thereafter, the thin film substrate was peeled off by hand. After each sample was peeled off, it was observed with a microscope, and the number of foreign matters originating from the temporary adhesive resin layer of 10 μm or more was counted. The case where 50 or more were counted in the range of 40 mm x 120 mm was judged as unacceptable, and the acceptance rate in all samples was evaluated.

<Peelability evaluation>
Using the same method as the heat resistance evaluation, as a thin film substrate, a glass “MICRO SLIDE GLASS S200423” made by Matsunami Glass Co., Ltd. having a thickness of 550 μm was used, and those cut into 50 mm × 50 mm were bonded together to prepare 50 evaluation samples. Created. After performing heat treatment at 180 ° C. for 2 hours in the same manner as in the heat resistance evaluation, peeling was performed. The sample in which the crack of the thin film substrate occurred at the time of peeling was judged as unacceptable, and the acceptance rate in all samples was evaluated.

<Pyrolysis evaluation>
About the resin layer for temporary adhesion of an Example and a comparative example, using the differential thermal analyzer "TG / DTA220" (made by SII Nano Technology Inc.), it was made to heat up at 200 degreeC (room temperature-200 degreeC). ) And a thermal decomposition rate at 300 ° C. (a thermal decomposition rate when the temperature was raised from room temperature to 300 ° C.). The measurement conditions were a heating rate of 10 ° C./min, an air atmosphere, and a flow rate of 200 ml / min. When the thermal decomposition rate was less than 0.2 wt%, it was evaluated as ◯, when it was 0.2 wt% to 1 wt%, Δ was evaluated when it was decomposed exceeding 1 wt%. When the thermal decomposition rate exceeded 1 wt%, it was judged as rejected.

<Solvent resistance test>
In the same procedure as the heat resistance evaluation, 100 evaluation samples were prepared for each of the temporary adhesion resin layers prepared in Examples and Comparative Examples.
50 samples of each were used, (1) immersed in 2% KOH aqueous solution at 30 ° C. for 30 minutes, (2) acetone stock solution was immersed for 5 minutes at room temperature, and the presence or absence of liquid intrusion was confirmed from the end. For each sample, the liquid intrusion area with respect to the total adhesion area was confirmed with an optical microscope (5 times magnification), and liquid infiltration rate = (liquid infiltration area / total adhesion area) × 100 (%) was evaluated. The average of the liquid penetration rate of 50 samples was calculated, and if the average liquid penetration rate was less than 1%, it was judged as acceptable.

  In Comparative Example 1 using the conventional heat-peelable pressure-sensitive adhesive, it was confirmed that the characteristics were particularly deteriorated in heat resistance, contamination, and solvent resistance, and the characteristics were inferior when used under high temperature and vacuum conditions. . On the other hand, in Examples 1 to 3 using the temporary bonding resin satisfying the requirements defined in the present invention, the thin film hard substrate does not float even during heating, and there is little decomposition due to heating and the problem of outgassing. It was confirmed that there was a remarkable effect that the solvent was not generated, the solvent resistance was excellent, and the peelability after heating was good.

DESCRIPTION OF SYMBOLS 1 Temporary bonding resin layer 2 Hard substrate 3 Hard substrate with temporary bonding resin layer 4 Thin film substrate 5 Thin film substrate laminated body 6 Surface treatment layer

Claims (13)

  A temporary bonding resin, which is a temporary bonding resin for temporarily bonding a thin film substrate to a hard substrate serving as a base when the thin film substrate is processed, and includes at least one fluororesin.   The temporary adhesive resin according to claim 1, wherein the fluororesin includes at least polytetrafluoroethylene.   A temporary adhesion resin layer formed from the temporary adhesion resin according to claim 1.   The thermal decomposition rate when the temperature is increased from room temperature to 200 ° C under conditions of a temperature increase rate of 10 ° C / min and an air atmosphere at a flow rate of 200 ml / min is 1 wt% or less. Resin layer for temporary bonding.   The resin layer for temporary adhesion according to claim 3 or 4, wherein the resin layer is a porous film.   The temporary adhesion resin layer according to any one of claims 3 to 5, wherein the resin layer is temporarily fired.   The resin layer for temporary adhesion according to any one of claims 3 to 6, wherein the resin layer is temporarily stretched. When processing the thin film substrate, it is a hard substrate with a temporary adhesion resin layer to temporarily bond the thin film substrate,
A hard substrate with a temporary adhesion resin layer, comprising: a hard substrate serving as a base; and the temporary adhesion resin layer according to any one of claims 3 to 7 provided on at least one surface of the hard substrate.   The hard substrate with a temporary adhesion resin layer according to claim 8, wherein the hard substrate serving as the pedestal is any one selected from a glass substrate, a silicon substrate, and a sapphire substrate.   A thin film substrate laminate formed by bonding a thin film substrate and a hard substrate serving as a pedestal with the resin layer for temporary bonding according to any one of claims 3 to 7.   11. The thin film substrate laminate according to claim 10, wherein the hard substrate serving as the pedestal is any one selected from a glass substrate, a silicon substrate, and a sapphire substrate. A thin film substrate processing process for processing a thin film substrate, at least,
The step (1) of bonding the thin film hard substrate and the hard substrate to be a pedestal with the resin layer for temporary bonding according to any one of claims 3 to 7,
Step (2) of performing heat treatment and / or chemical treatment
And a step (3) of peeling the thin film substrate,
A thin film substrate processing process characterized by comprising:   The chemicals used in the chemical treatment process are hydrofluoric acid, oxalic acid, acetone, N-methyl-2-pyrrolidone (NMP), dimethyl sulfoxide (DMSO), toluene, aqueous potassium hydroxide (KOH), tetramethyl hydroxide. 13. The thin film substrate processing process according to claim 12, which is at least one selected from an aqueous ammonium solution (TMAH), diethylene glycol monobutyl ether (BGD), monoethanolamine (MEA), aluminate, and isopropyl alcohol. .

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