KR101456724B1 - Method and apparatus for manufacturing wafer, and curable resin composition - Google Patents

Abstract

An object of the present invention is to eliminate warping and bending of a wafer in a grinding process step of a wafer surface without causing warping of the wafer during curing of a coated layer of the curable material.

(A) preparing a wafer, (B) a curing resin composition layer forming step of coating a specific curable resin composition on the first surface of the wafer to a thickness of 10 to 200 mu m, and (C) A planarizing step of pressing the second surface of the wafer coated with the curable resin composition with a pressing means to planarize the curable resin composition layer applied to the first surface, (D) (E) a first grinding step of grinding the second surface of the wafer fixed on the curable resin composition layer, (F) a second grinding step of grinding the second surface of the wafer on the reference surface And a second grinding step of grinding the first surface.

Description

TECHNICAL FIELD [0001] The present invention relates to a method and a device for manufacturing a wafer, and a method of manufacturing a curable resin composition,

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a method for manufacturing a wafer used in a semiconductor device, and more particularly to a means for eliminating warpage and waviness of a wafer which occurs when a single crystal ingot represented by silicon is sliced.

Conventional wafer fabrication is produced, for example, by the process shown in Fig. First, in step S10, for example, a single crystal ingot manufactured by a single crystal pulling method is subjected to outer periphery grinding, and then subjected to, for example, orientation flat processing or notch processing for positioning in the crystal direction, The ingot is sliced (step S10: slicing step). Subsequently, in step S20, the outer peripheral portion of the sliced wafer is chamfered (step S20: chamfering step) by the grinding stone, and then in step S30, the thickness is made uniform by the lapping step or the double-head grinding step .

Thereafter, in step S40, the grinding wheel grinds (grinds) the wafer surface one surface or both surfaces at the same time to eliminate the bending of the wafer caused by the slice, thereby flattening the both surfaces of the wafer. At this time, when the both surfaces of the wafer are ground by the grinder, a damaged layer occurs on the surface of the wafer. Thus, in step S50, the damaged layer is removed by polishing with acid or alkali by etching or chemical mechanical polishing (CMP).

Conventionally, wafers typified by silicon are produced in this way. However, since the number of processes from the single crystal ingot to the wafer production is large, a simplification of the wafer manufacturing process has been demanded.

Thus, it has been studied to omit the lapping process or the double-head grinding process. However, there has been a problem in that warpage and bending of the surface of the wafer, which occurs at the time of slicing the single crystal ingot, can not be removed by a normal grinding process.

A method for eliminating such bending is disclosed in Patent Document 1 or Patent Document 2. In these methods, first, wax or resin is coated on either side of the sliced wafer and the wafer is cured. When curing, a flat plate is pressed against the surface of the wax or resin so that the surface of the cured resin becomes a uniform flat surface (reference plane). Subsequently, after the wax or the resin is cured, the surface of the chuck table is brought into contact with the cured surface downward, and the wafer is held on the chuck table. Further, the upper surface of the wafer held on the chuck table is ground by the grinding wheel. Thus, a uniform flat surface can be formed by removing the bending on the surface and grinding a necessary amount. Thereafter, the wafer is held on the chuck table with the flat surface formed on the upper surface of the wafer downward. After removing the hardened wax or resin before grinding, the other surface of the wafer is subjected to bending removal and grinding, so that the wafer can be finished to a predetermined thickness while flattening the surface.

However, in the above method, since the thickness of the wax or resin coated on the surface of the wafer is not specified, the following problems may occur depending on the thickness. For example, if the thickness of the resin coated on the wafer is excessively thin, the bending can not be sufficiently absorbed by the resin or the like, and the bending is transferred to the processed surface of the wafer at the time of grinding. On the other hand, if the thickness of the resin or the like coated on the wafer is excessively large, the wafer is repelled from the grinding stone by the elastic action of the resin or the like, so that the wafer can not be ground to a uniform thickness even if the bending of the surface can be removed .

In order to solve such a problem, Patent Document 3 and Patent Document 4 disclose a surface-fixing means for providing a reference surface on a wafer surface by using a paste-type hardening material, and by using this hardening material, Technology has been proposed.

Patent Document 3 discloses only the use of an adhesive material as a means for fixing a wafer as a structure for absorbing warping and bending. Patent Document 4 discloses a technique of absorbing bending by coating a curable material to a specific thickness.

However, it is difficult to remove both the warp and curvature of the wafer surface at the same time, and when a curable resin composition is used, since shrinkage due to curing occurs after coating and curing on a substrate, Warpage occurs. For this reason, there has been a demand for development of a material capable of eliminating warping and bending of the wafer during grinding and suppressing warping of the wafer upon curing of the curable resin composition.

[Patent Document 1] Japanese Patent Application Laid-Open No. 11-111653

[Patent Document 2] Japanese Unexamined Patent Publication No. 2000-5982

[Patent Document 3] Japanese Patent Application Laid-open No. Hei 8-66850

[Patent Document 4] Japanese Patent Application Laid-Open No. 2006-269761

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and an object of the present invention is to provide a curable resin composition coated with a curable resin composition, which does not cause warping of the cured resin composition coated on the surface of the wafer, The present invention provides a new and improved wafer manufacturing method and apparatus capable of grinding a wafer with a required thickness, and a curable resin composition used in the above manufacturing method.

The present invention designed to solve the above problems is a wafer manufacturing method having the following constitution. In other words,

(A) a step of preparing a thin plate-like wafer obtained by slicing from an ingot,

(B) a curable resin composition layer forming step of coating a curable resin composition having the following characteristics (b1) and (b2) on the first surface of the wafer at a film thickness of 10 m to 200 m;

(b1) Curing shrinkage is not more than 7%

(b2) the value of at 25 ℃ of storage modulus (E ') of the cured resin ^{1.0 × 10 6 ㎩~3.0 × 10 9} ㎩

(C) a planarizing step of planarizing the curable resin composition layer applied to the first surface by pressing the second surface of the wafer coated with the curable resin composition by a pressing means,

(D) a curing resin composition layer immobilization step of irradiating an active energy ray onto the curable resin composition layer coated on the wafer after the pressurization by the pressing means is released,

(E) a first grinding step of grinding the second surface of the wafer fixed on the curable resin composition layer in a flat manner,

(F) a second grinding step of grinding the first surface with the second surface of the wafer flattened by the first grinding step as a reference surface.

The present invention also relates to an apparatus for manufacturing a wafer used in a method of manufacturing the wafer. A stage having a substantially horizontal holding surface for holding the first surface of the wafer coated with the curable resin composition so as to expose the second surface of the wafer coated with the curable resin composition; An active energy ray irradiating means for irradiating an active energy ray to the curable resin composition applied to the wafer, and a second active energy ray irradiating means for irradiating the active energy ray to the second side of the wafer fixed on the curable resin composition layer And a second grinding means for grinding the first surface with the second surface of the wafer flattened by the first grinding means as a reference surface Wherein the wafer is a wafer.

In this method for producing a wafer, a specific curable resin composition is coated on the first surface of a wafer obtained by slicing from an ingot to form a curable resin composition layer. As the coating method, it is possible to carry out by coating a curable resin composition in advance on a light-transmitting member such as a PET film, and placing a wafer on the curable resin composition layer. However, unless specifically impeding the function of the present invention, It does not. Subsequently, in order to make the surface of the side on which the curable resin composition layer is formed to be the reference surface, the wafer is uniformly pressed by a pressing means such as a flat plate member or the like so that the side on which the curable resin composition layer is present is the bottom surface, do. Then, the curable resin composition layer is irradiated with active energy rays such as ultraviolet rays, electron beams, and gamma rays to cure the curable resin composition layer. At this time, after the pressing means is separated from the wafer, the active energy ray is irradiated to cure the curable resin composition layer. This is to prevent internal stress from remaining in the curable resin composition layer. The wafer is placed so that the flat surface is in contact with a member such as a chuck table constituting the wafer holding means, and the second surface of the wafer on the other side of the flat surface is ground. Here, the curable resin composition is characterized in that the storage modulus (E ') at 25 ° C is 1.0 × 10 ⁶ Pa to 3.0 × 10 ⁹ Pa. By setting the thickness to 10 μm to 200 μm, The warpage and bending of the wafer can be sufficiently absorbed by the layer of the curable resin composition and warping and bending are not transferred to the processed surface of the wafer in the grinding process. Further, the surface of the wafer can be ground to a uniform thickness by appropriate elastic action of the curable resin composition layer. In addition, since the curable resin composition layer has a characteristic that the curing shrinkage rate is 7% or less, a phenomenon that the wafer follows the shrinkage of the curable resin composition and causes a new warp in the wafer during curing can do.

In this manner, the second surface of the wafer is processed into a uniform flat surface with no warping or bending by the grinding process, without performing the lapping process or the double-head grinding process. Thereafter, the first surface of the wafer is processed, wherein the layer of the curable resin composition coated on the first surface may be removed before grinding the first surface. As the removing method, it is preferable to remove the layer by immersing it in hot water (hot water) at 60 ° C to 90 ° C to easily peel off the layer of the curable composition of the present invention. However, But may be removed by, for example, organic solvent immersion or steam steam or the like. When the curable resin composition layer is formed on a film, the curable resin composition layer can be easily peeled off by peeling off the film. Thereafter, the wafer is placed on a holding member such as a chuck table and the first surface is ground so that the second flat surface is contacted. At this time, since the second surface that is in contact with the fixing member is a flat surface, the first surface is not warped or bent, and the flat surface of uniform thickness can be processed.

As described above, instead of grinding the first surface after removing the curable resin composition layer as described above, the curable resin composition layer is attached on the first surface of the wafer without removing the layer of the curable resin composition, The first surface of the wafer may be ground together with the curable resin composition layer. As described above, the removal of the curable resin composition and the warping and bending of the wafer can be performed by one cutting step, and the wafer can be processed into a flat surface having a uniform thickness.

In the present invention, the curable resin composition layer may be formed by previously coating a curable resin composition on a light-transmitting flexible thin film and placing the wafer on the curable resin composition of the film after the treatment. By forming the curable resin composition layer on the film, it is possible to easily peel off the wafer from the wafer when the first surface of the wafer is processed and then remove the curable resin composition layer, so that the peeling step can be simplified, It is possible to reduce the possibility that an excessive stress is applied to the wafer, thereby damaging the wafer. As the material of the film, PET and polyolefin are particularly preferable because they are excellent in flexibility and good followability of the curable resin composition layer, but the present invention is not limited thereto.

The present invention also relates to a curable resin composition for use in the method for producing a wafer. That is, the curable resin composition is characterized by having the following characteristics (b1) and (b2).

(b1) Curing shrinkage is not more than 7%

(b2) the value of at 25 ℃ of storage modulus (E ') of the cured resin ^{1.0 × 10 6 ㎩~3.0 × 10 9} ㎩

INDUSTRIAL APPLICABILITY As described above, according to the present invention, in the grinding step, warping and bending of the wafer surface generated at the time of slicing can be eliminated, and the wafer is ground to a required thickness without causing a new warp on the wafer surface And a curable resin composition for use in the above-mentioned production method can be provided.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the present specification and drawings, constituent elements having substantially the same functional configuration are denoted by the same reference numerals, and redundant description will be omitted.

First, a method of manufacturing a wafer of the present invention will be described with reference to the drawings. 1 is a flowchart showing a method of manufacturing a wafer according to an exemplary embodiment of the present invention. Fig. 2 is a schematic diagram for explaining the steps (A) to (F) in the method of manufacturing a wafer.

The present invention eliminates warping and surface bending of a wafer which can not be removed by a conventional grinding process in a grinding process in a manufacturing method of a wafer.

In the step (A) of the method for producing a wafer of the present invention, as shown in Fig. 1, a single crystal ingot is first sliced to obtain a sliced wafer (step S110: slicing step). In step S110, for example, the single crystal ingot produced by the single crystal pulling method is subjected to the outer periphery grinding, and then subjected to, for example, orientation flat processing or notch processing for positioning in the crystal direction. Then, the single crystal ingot is sliced by a wire saw to obtain a wafer.

Subsequently, in step (B), a curable resin composition is coated on the first surface of the sliced wafer to form a curable resin composition layer (step S120: curable resin composition layer formation step). As shown in Fig. 2 (a), sliced wafers 10 have warpage and curvature generated when the single crystal ingot is sliced. When these reference surfaces and the other machining surface are ground by placing the surfaces with the curvature and curvature as reference surfaces on the holding member 12 such as a chuck table, the bending is transferred to the machining surface. Therefore, it is necessary to form a flat reference surface, and a curable resin composition is coated on the first surface 10a of the wafer 10 to form a flat surface.

The method of coating the curable resin composition on the first surface 10a of the wafer 10 in step S120 is not particularly limited and may be, for example, film formation of a curable resin composition, spin coating, screen printing, roll coater, die coater, A curtain coater or the like. 2 (b), a curable resin composition is applied to a transparent thin film 11 having a light transmittance in advance to form a curable resin composition layer, and the wafer 10 is placed on the curable resin composition layer 20, The curable resin composition layer 20 is formed on the first surface 10a of the wafer 10. In this case,

The thickness of the curable resin composition layer 20 to be coated is 10 占 퐉 to 200 占 퐉, preferably 20 占 퐉 to 100 占 퐉. By forming the curable resin composition layer 20 having a thickness in this range, it is possible to sufficiently absorb the warpage and bend existing on the wafer surface. If the film thickness is smaller than 10 탆, the curable resin composition layer 20 can not sufficiently absorb the impact during grinding of the wafer 10, and warpage and bending remain. If the film thickness is larger than 200 탆, It is thrown away from the grinding stone at the time of grinding, and as a result, warping and bending remain. When the thickness is larger than 200 탆, when the curable resin composition layer 20 is peeled off by hot water immersion, moisture can not penetrate sufficiently into the adhesive interface, and it is difficult to peel off without residue.

The curable resin composition to be coated herein preferably has a curing shrinkage ratio of 7% or less (b1), a value of the storage modulus of the cured product at 25 占 폚 of 1.0 x 10 ⁶ Pa to 3.0 x 10 ⁹ Pa, more preferably 5.0 × 10 ⁶ Pa to 1.5 × 10 ⁹ Pa. If the hardening shrinkage exceeds 7%, the wafer 10 follows the curable resin composition when the curable resin composition is cured, and the wafer 10 is warped. If the value of the storage elastic modulus of the cured product at 25 캜 exceeds 3.0 x 10 ⁹ Pa, the warpage and bending of the wafer 10 can not be absorbed. If the value is less than 1.0 x 10 ⁶ Pa, Is bounced off the grinding stone, and warping and bending are transferred to the machining surface, and the warping and the bending are left on the wafer surface, respectively.

The curable resin composition having the above-mentioned characteristics is not limited in its kind, but in the present invention, (A) a polyester di (meth) acrylate, a polyurethane di (meth) acrylate, an epoxy di (Meth) acrylic compound having at least two (meth) acrylic groups in the molecule and (c) a photopolymerization initiator having at least two (meth) acrylic groups, It is preferable that the curable resin composition is a curable resin composition. Further, (meth) acryl is a generic name of acrylic and methacrylic as is commonly used.

Here, each component of (a), (b), and (c) will be described. The component (A) preferably used in the present invention is at least one selected from a polyester (meth) acrylate, a polyurethane (meth) acrylate and an epoxy (meth) acrylate having a (meth) Is not particularly limited. Polyester (meth) acrylate is a compound having a main chain structure of a polyester obtained by reacting a polyol and a polybasic acid, and having at least two acrylic groups at both ends of the molecular chain. Polyurethane (meth) acrylate is a compound having a main chain skeleton of a polyurethane obtained by reacting a polyol and a polyisocyanate, and having at least an acrylic group at both terminals of the molecular chain. The epoxy (meth) acrylate refers to an epoxy resin having at least two glycidyl groups in the molecule, such as bisphenol A or bisphenol F type epoxy resin, phenol novolak type epoxy resin, cresol novolak type epoxy resin, (Meta) acrylic compound having a (meth) acrylic group at both ends of a molecular chain synthesized by reacting a glycidyl group with a (meth) acrylic acid. In the present invention, it is particularly preferable that the number average molecular weight of the component (A) is 600 to 1800 in order that the curing shrinkage ratio of the curable resin composition is 7% or less.

The component (b) preferably used in the present invention is not particularly limited as long as it is a hydrophilic (meth) acrylic compound having at least two (meth) acrylic groups in the molecule. As used herein, the term " hydrophilic " means a molecule having a polar atom or atomic group with high polarity and having a certain solubility in water or hot water, and examples thereof include a polyalkylene glycol structure such as polyethylene glycol and polypropylene glycol, (Meth) acrylic compounds having a polyethylene glycol structure (polyethylene glycol di (meth) acrylate) having a structure, an alcohol structure, and other polar functional groups in the molecule. Acrylate] is preferred. The term "polyethylene glycol structure" as used herein means a structure having two or more repeating units of - (CH ₂ CH ₂ O) -.

In the present invention, in order for the cured product of the curable resin composition to have a storage elastic modulus at 25 ° C of 1.0 x 10 ⁶ Pa to 3.0 x 10 ⁹ Pa, the number average molecular weight of the polyethylene glycol di (meth) Is preferably used. When the curable resin composition layer 20 is formed on a PET film, polyethylene glycol di (meth) acrylate is used as the component (b), and the curable resin composition layer 20 The residue can be easily removed without removing the residue.

As the component (c), a polymerization initiator commonly used for the (meth) acrylic resin can be used. In the present invention, it is preferable to use a photopolymerization initiator for the purpose of imparting photocurability to the curable resin composition. Examples of the photopolymerization initiator include benzophenone, acetophenone, Michler's ketone, benzyl, benzoin, benzoin methyl ether, benzoin ethyl ether, tetramethylthiuramsulfide, thioxanetrichlorotoxane, benzyldimethyl ketal, Mates, and the like. Examples of commercially available products include DAROCURE 1173 (2-hydroxy-2-methyl-1-phenylpropan-1-one), IRGACURE 2959 (1- [4- (2-hydroxyethoxy) -phenyl] IRGACURE 184 (1-hydroxycyclohexyl phenyl ketone), IRGACURE 651 (2,2-dimethoxy-1,2-diphenylethane-1-one), IRGACURE 369 (2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butanone-1), IRGACURE 379 -Morpholin-4-yl-phenyl) -butan-1-one), IRGACURE 819 (bis (2,4,6-trimethylbenzoyl) -phenylphosphine oxide, available from Chiba Specialty Chemicals). Among them, IRGACURE 184 is particularly preferred in the present invention from the viewpoints of curability, preservability and releasability.

In order to set the curing shrinkage of the cured product to 7% or less and the storage elastic modulus (E ') of the cured product at 25 ° C to 1.0 x 10 ⁶ Pa to 3.0 x 10 ⁹ Pa in the curable resin composition having the above- Is preferably 30 kJ / m < 2 > but is not limited thereto, and is not particularly limited as long as the curing shrinkage percentage and the storage elastic modulus of the cured product fall within the specified ranges.

From the viewpoint of workability at the time of coating, the curable resin composition preferably has a viscosity at the time of uncured curing of 1000 mPa · s to 50000 mPa · s, more preferably 3000 mPa · s to 10000 mPa · s, Is preferably in the range of 4500 mPa · s to 6500 mPa · s. If the viscosity of the curable resin composition is less than 1000 mPa · s at the time of uncured curing, the coating film having a constant thickness can not be formed because of the shape retentiveness being too small, and formation on the film is also difficult. If the viscosity at the time of uncured is larger than 50000 mPa · s, the flowability is too low, which makes the coating process itself difficult.

The curable resin composition used in the present invention may contain a coloring agent such as pigment and dye, a reactive diluent such as a low molecular weight monomer, a transparent filler such as fumed silica and glass microspheres, Inorganic fillers such as calcium carbonate, magnesium carbonate, calcium sulfate, calcium silicate, barium sulfate, barium titanate, amorphous silica, clay, clay, diatomaceous earth, graphite, talc, carbon, silica, spinel, alumina, aluminum hydroxide, A plasticizer, an antioxidant, a defoaming agent, a coupling agent, a leveling agent, and a rheology control agent. By these additions, a curable resin composition having more preferable physical properties can be obtained.

By using the curable resin composition having the above-described constitution in the present invention, it is possible to absorb the bending of the wafer 10 as a deposition member during grinding and to easily cure the cured product of the curable resin composition from the wafer 10 It can peel off.

The curable resin composition used in the present invention is intended to prevent the influence of heat on the wafer at the time of curing and is a photosensitive resin composition which is cured by irradiating active energy rays such as ultraviolet rays, electron beams and gamma rays. The curing of the curable resin composition is carried out by irradiating active energy rays after separating the pressing means 13 from the wafer 10. [ This is to prevent the internal stress from remaining in the curable resin composition layer 20. When the internal stress is left in the curable resin composition layer 20, when the curable resin composition layer is removed from the wafer 10 after the grinding process, the wafer 10 is released from the internal stress, .

Subsequently, the surface of the curable resin composition layer 20 coated on the first surface 10a of the wafer 10 is processed flat (step S130: planarization step). 2 (c), before the curable resin composition is cured, a pressing member 13 such as a flat plate member, for example, a ceramic plate having a high flatness, The resin composition layer 20 is pressed uniformly. At this time, the coated surface of the curable resin composition is placed on the stage 12 having a flat horizontal holding surface. When the surface of the curable resin composition coated with the curable resin composition, for example, on the surface of the light transmitting film 11, the active energy ray is irradiated from the surface having the light transmitting film 11, The composition layer 20 is cured (step S140: curable resin composition layer immobilization step). By this process, the surface of the curable resin composition layer 20 on the opposite side of the wafer 10 becomes a cured body formed with a uniform flat surface. Since the curing shrinkage ratio of the cured product of the curable resin composition is 7% or less, new bending due to the wafer 10 following shrinkage of the curable resin composition due to the curing at this time does not occur and a flat surface is formed, the flat surface of the curable resin composition can be used as a reference surface when the second surface 10b of the wafer 10 is processed, as shown in Fig.

Thereafter, the second surface 10b of the wafer 10 is ground (step S150: first grinding step). In this step, the wafer 10 is placed on the flat fixing member 12 such as a chuck table of a grinding apparatus so that the flat surface of the curable resin composition serving as the reference surface is placed on the chuck table by vacuum suction or the like . Thereafter, the driving force of the motor is transmitted through a spindle or the like, and the chuck table is rotated at a predetermined speed in the horizontal direction. Then, the driving force of the motor is transmitted from the upper side of the chuck table through the spindle and the diamond wheel, and the grinding stone is lowered while rotating at high speed. Then, the grinding wheel is pressed against the second surface 10b of the wafer 10, and the wafer 10 is ground until the wafer 10 has a predetermined thickness. Thus, the bending of the second surface 10b can be removed, and the wafer 10 can be ground to a required thickness. In this way, the machined surface 10b is formed into a uniform flat surface from which the bend is removed as shown in Fig. 2 (e).

At this time, since the wafer 10 is fixed on the flat fixing member 12 by vacuum suction or the like of the vacuum adsorption device, the relative position of the wafer 10 does not change even when a large stress acts on the wafer 10. [ The cured resin composition layer 20 cured to a specific thickness is integrally and firmly formed on the wafer 10. The cured product of the curable resin composition has a value of E 'at 25 ° C of 1.0 × 10 ⁶ Pa 3.0 x 10 < ⁹ > Pa, elastic deformation does not occur on the wafer 10 because the curable resin composition layer 20 absorbs this stress even when a large stress acts on the wafer 10, Therefore, the curvature can be eliminated. Also, the warpage of the wafer 10 due to curing of the curable resin composition can be remarkably reduced by the property that the cured shrinkage percentage of the cured resin composition is 7% or less.

In the next step, the wafer 10 integrated with the curable resin composition layer 20 is reversed (Fig. 1 (f)). At this time, the curable resin composition layer 20 coated on the wafer 10 may be removed Step S160: Curable resin composition layer removing step). In step S160, the curable resin composition layer 20 coated on the first surface 10a is removed before the first surface 10a is processed, but without removing the curable resin composition layer 20 in this step, In the next second grinding step, the wafer may be ground and the curable resin composition layer 20 may be grind-removed. The method of removing the curable resin composition layer 20 is not particularly limited and a method of dissolving and removing the curable resin composition layer 20 with a solvent and a method of modifying the curable resin composition layer 20 by radiation such as light A method of peeling off the curable resin composition layer 20 by applying a force in a direction in which the coated layer of the curable resin composition 20 is easy to peel off or a method of dipping in hot water of 60 to 90 占 폚 to form a curable A method of peeling off the resin composition layer 20 by swelling the resin composition layer 20, or the like. When the curable resin composition layer 20 is formed on the light transmitting film 11, it can be peeled off easily together with the light transmitting film 11. [ In addition, although the curable resin composition layer 20 remains on the first surface 10a of the wafer 10, the residue is also removed in the subsequent second grinding step.

After the wafer is inverted by the above step, the first surface 10a is ground (step S170: second grinding step). As shown in FIG. 2 (g), in step S170, the wafer 10 is placed on the fixing member 12 such that the second surface 10b processed in step S140 abuts on a flat fixing member 12 such as a chuck table. (12). The grinding wheel is then pressed against the first face 10a of the wafer 10 to grind the first face 10a to remove the curvature of the first face 10a and move the wafer 10 to a desired thickness Grinding can be done. Thus, the bending of the first face 10a and the second face 10b is removed as shown in FIG. 2 (h), and a wafer ground to a predetermined thickness is formed.

Here, after the curable resin composition layer 20 is removed in step S160, the first surface 10a is ground in step S170, but step S160 may be omitted. In this case, after the second surface 10b is ground in step S150, the wafer 10 is placed on the second surface 10b so that the second surface 10b is in contact with the fixing member 12. [ Subsequently, the grinding wheel is pressed against the curable resin composition layer 20 to grind and remove the curable resin composition. As the grinding proceeds, the grinding wheel reaches the first surface 10a and further grinds the wafer 10, thereby removing the bending of the first surface 10a and cutting the wafer 10 to a predetermined thickness . As described above, the one-pass grinding can remove the curable resin composition and grind the first surface 10a, thereby eliminating the bending of the first surface 10a and the second surface 10b, To form a wafer ground.

Thereafter, it is preferable to remove the damaged layer by polishing the wafer with acid or alkali, or CMP (Chemical Mechanical Polishing) (Step S180).

The manufacturing method of the wafer according to the present embodiment has been described above. The present invention is characterized in that the cured material properties of the curable resin composition to be coated in step S120 are specified as follows. (b1) the curing shrinkage ratio of the cured product is 7% or less, and (b2) the storage elastic modulus (E ') of the cured product at 25 ° C is 1.0 × 10 ⁶ Pa to 3.0 × 10 ⁹ Pa. The curable resin composition having such characteristics is preferably selected from polyester di (meth) acrylate, polyurethane di (meth) acrylate, and epoxy di (meth) acrylate, (Meth) acrylic compound having at least two (meth) acrylic groups, (b) a hydrophilic (meth) acrylic compound having at least two (meth) acrylic groups in the molecule, and (c) a photopolymerization initiator.

The present invention also includes a wafer manufacturing apparatus capable of realizing the above process. For example, a film-like film 100 having a light-transmitting property capable of carrying a wafer, i.e., a device shown in Fig. 3, and a resin coating means (not shown) for supplying and coating a curable resin composition onto the surface of the film 100 (Not shown) for feeding and placing a wafer 110 on a film 100 coated with a curable resin composition and a wafer 110 placed on the film 100 are uniformly placed on the stage 120, A curing means 130 for curing the curable resin composition on the surface of the wafer 110 by irradiating an active energy ray to the wafer 110 and a curing means 130 for curing the curable resin composition A cutting means 140 for cutting the wafer 110 together with the film 100 so as to surround the wafer 110 and a non-planarized surface of the wafer 110 cut together with the film 100 The first grinding means A second grinding means for grinding the other surface that has not been planarized after the wafer 110 having been ground on one side is inverted in front and back, and the like, but the present invention is not limited thereto .

To describe the manufacturing apparatus in detail, a film 100 formed in a roll shape is fed out from one end of the motor and wound around the other end of the motor.

In the resin applying means 101, the liquid curable resin composition is coated on the film 100 by a slit coater or the like, and then the wafer 110 is supplied from the wafer supplying means (not shown) onto the applied curable resin composition After the wafer 110 and the film 100 are sandwiched between the rollers, the wafer 110 and the film 100 are transferred to the pressing means 121.

A curing unit 130 is disposed inside the stage 120 of the pressing unit 121 and the UV lamp 131 is irradiated from the film side to cure the curable resin composition. A blocking means 132 is provided at an upper portion of the UV lamp 131. When the blocking means 132 is closed, all the light generated from the UV lamp 131 is blocked. A filter 133 for blocking light other than ultraviolet light is disposed on the blocking means 132. Since the temperature of the inside of the stage 120 is raised by the irradiation of the UV lamp 131 and the stage 120 may be thermally expanded, the atmosphere inside the atmosphere is discharged to the outside by the exhaust means 135 have.

The cutting means 140 has a ring-shaped cutting edge portion larger than the diameter of the wafer 110 and cuts the wafer 110 together with the film 100 so as to surround the wafer 110 on the stage.

Subsequently, the wafer 110 advances in the direction of the arrow and is accommodated in a cassette or the like. Then, only the cut film 150 around the wafer is wound.

Thereafter, the wafer 110 is transported to the grinding apparatus, and the surface is ground smoothly.

The present invention also includes a curable resin composition used in the above-described method for producing a wafer, wherein the curable resin composition of the present invention satisfies the above-mentioned (b1) and (b2).

<Examples>

Hereinafter, the present invention will be described in more detail with reference to examples and comparative examples, but the method for producing a wafer of the present invention is not limited to these examples.

The following apparatuses and conditions were applied to manufacture a wafer according to the present invention.

Substrate wafer:? 200 mm Silicon (wire top finish) as slice wafer.

Curing shrinkage ratio: The volume shrinkage ratio defined in JIS-K-6901 was used to cure the curable resin composition under an irradiation light quantity of 30 kJ / m &lt; 2 &gt; times twice and change in volume before and after curing was measured, .

Storage elastic modulus: The storage elastic modulus of the cured product was measured by using a viscoelastic spectrometer (DMS, manufactured by SII ANA NanoTechnology Co., Ltd.) and curing the curable resin composition under an irradiation condition of 30 kJ / m &lt; 2 &gt;

Evaluation of film formability: When the curable resin composition was applied on a PET film having a thickness of 75 占 퐉 to a predetermined thickness using a slit coater, whether or not a film integrated with the curable resin composition layer can be formed Respectively. It was found that a curable resin composition layer having a constant film thickness could be obtained and that a curable resin composition layer having a constant film thickness could not be formed due to too high fluidity or problematic workability, Respectively. In Example 6, the curable resin composition was applied directly to the wafer without using a film.

Warping evaluation: The WARP and the best fit were measured by an optical interference flatness measuring apparatus (manufactured by ADE). When the warpage was not more than about 8 占 퐉,? Was not more than 10 占 퐉 and? Was not more than 10 占 퐉.

Flexural evaluation: Magic mirror observation was carried out by YIS-3000 manufactured by Yamashita Denso Corporation, and the residual property of the curvature was visually evaluated. As shown in Fig. 4, the bending was completely lost. The bending was almost eliminated as shown in Fig. 5, and the bending was observed as bending as shown in Fig.

Film delamination: When the layer of the curable resin composition formed on the film was peeled off, the layer in which the layer of the curable resin composition was able to be peeled off without residue was indicated as "Good" and the remaining portion was indicated as "Failed".

The curable resin compositions used in Examples and Comparative Examples are as follows.

Curable resin composition A: 60 parts by weight of polyurethane diacrylate (Mn 1600), 40 parts by weight of polyethylene glycol diacrylate (Mn 550), 5 parts by weight of cleavage type radical polymerization initiator (IRGACURE 184) And 3 parts by weight of a modifier (dry silica powder).

Curable resin composition B: 50 parts by weight of polyurethane diacrylate (Mn 1600), 50 parts by weight of polyethylene glycol diacrylate (Mn 550) and 5 parts by weight of a cleavable radical polymerization initiator.

Curable resin composition C: 65 parts by weight of epoxy diacrylate (Mn 1500), 35 parts by weight of polyethylene glycol diacrylate (Mn 1150), 5 parts by weight of a cleavable radical polymerization initiator, and 3 parts by weight of a viscosity adjusting agent.

Curable resin composition D: 60 parts by weight of polyester diacrylate (Mn 1200), 40 parts by weight of polyethylene glycol diacrylate (Mn 550), and 5 parts by weight of a cleavable radical polymerization initiator.

Curable resin composition E: 30 parts by weight of polyurethane diacrylate (Mn 1600), 20 parts by weight of polyethylene glycol diacrylate (Mn 550), 50 parts by weight of acrylic monomer, and 5 parts by weight of cleavable radical polymerization initiator.

Curable resin composition F: 65 parts by weight of polyurethane diacrylate (Mn 1600), 35 parts by weight of 2-hydroxy-3- (acryloyloxy) propyl methacrylate, 5 parts by weight of a cleavable radical polymerization initiator, And 5 parts by weight of a modifier.

Curable resin composition G: 50 parts by weight of polyurethane diacrylate (Mn 2000), 50 parts by weight of polyethylene glycol diacrylate (Mn 550), 5 parts by weight of a cleavable radical polymerization initiator, and 4 parts by weight of a viscosity adjusting agent.

Curable resin composition H: 50 parts by weight of polyester monoacrylate (Mn 950), 50 parts by weight of polyethylene glycol diacrylate (Mn 800), 20 parts by weight of alicyclic monoacryl monomer, 5 parts by weight of cleavable radical polymerization initiator, And 11 parts by weight of a viscosity adjusting agent.

Curable resin composition I: 50 parts by weight of epoxy diacrylate (Mn 1500), 50 parts by weight of polyethylene glycol monoacrylate (Mn 360), 5 parts by weight of a cleavable radical polymerization initiator, and 7 parts by weight of a viscosity adjusting agent.

Curable resin composition J: 65 parts by weight of epoxy diacrylate (Mn 1500), 35 parts by weight of a hydroxyalkylmonoacryl monomer, 5 parts by weight of a cleavable radical polymerization initiator, and 7 parts by weight of a viscosity adjusting agent.

Curable resin composition K: 100 parts by weight of polyethylene glycol diacrylate (Mn 800), 5 parts by weight of a cleavage type radical polymerization initiator, and 10 parts by weight of a viscosity adjusting agent.

In Comparative Example 1, the surface of the wafer was ground without using the curable resin composition, but a large warpage remained as a result of the flatness measurement, and a curvature remained on the surface as shown in the photograph of the magic mirror in FIG. On the other hand, all of the wafers manufactured using the curable resin composition included in the constitution of the present invention were all free from warping and surface bending.

Even in the case of using the curable resin composition, it can be seen that the warp of the wafer and the bending of the surface remain in the curable resin composition which does not satisfy the requirements (b1) and (b2) according to the present invention. That is, it can be seen that the hardening shrinkage rate is larger than 7%, or that the storage elastic modulus is larger than 3.0 x 10 ⁹ Pa or smaller than 1.0 x 10 ⁶ Pa, warpage or curvature remains on the wafer surface. Even curing shrinkage percentage is less than 7%, the storage elastic modulus is 1.0 × 10 ⁶ ㎩~3.0 × not in the range of 10 ⁹ ㎩ warp, bending, and both remaining, opposed to storage modulus is 3.0 × 10 ⁹ ㎩ below even the curing shrinkage ratio of 7% If it is larger, the bending is eliminated, but the bending remains. This is considered to be caused by warping of the wafer due to curing shrinkage of the curable resin composition. It was also confirmed that even if the curing shrinkage ratio and the storage elastic modulus were all within the specified range, the warpage and bending could not be eliminated if the film thickness was larger than 200 탆.

According to the present invention, it is possible to provide a high-quality wafer because the wafer can be processed with high precision and smoothness in grinding.

1 is a flowchart showing a method of manufacturing a wafer of the present invention.

2 is a schematic view for explaining a coating step of the present invention and a surface processing step of a curable resin composition layer.

3 is a schematic diagram of an example of a wafer manufacturing apparatus of the present invention.

4 is a photograph of a mirror mirror observation of a wafer in which bending is completely lost.

5 is a photograph of a mirror mirror observation of a wafer in which the bending is almost lost.

FIG. 6 is a photograph of a mirror mirror observation of a wafer in which the residual curvature is visible.

Fig. 7 is a photograph of a mirror mirror observation of a wafer produced without using a curable resin composition. Fig.

8 is a flowchart showing a conventional method of manufacturing a wafer.

Description of the Related Art

10: wafer 10a: first surface of the wafer

10b: second surface 11 of the wafer: translucent film

12: flat fixing member 13: flat plate-like pressing member

20: Curable resin composition layer

Claims (6)

A method of manufacturing a wafer, (A) a pre-process for preparing a thin plate-like wafer obtained by slicing from an ingot (B) a curable resin composition layer forming step of coating a curable resin composition having the following characteristics (b1) and (b2) on the first surface of the wafer at a film thickness of 10 m to 200 m (b1) Curing shrinkage is not more than 7% (b2) the value of at 25 ℃ of storage modulus (E ') of the cured resin ^{1.0 × 10 6 ㎩~3.0 × 10 9} ㎩ (C) a planarizing step of planarizing the cured resin composition layer applied to the first surface by pressing the second surface of the wafer coated with the curable resin composition by the pressing means (D) a step of immobilizing the curable resin composition layer, which is cured on the surface of the wafer, by irradiating the active energy ray onto the curable resin composition layer coated on the wafer after releasing the pressure by the pressing means (E) a first grinding step for grinding the second surface of the wafer fixed on the curable resin composition layer in a flat manner (F) a second grinding process for grinding the first surface with the second surface of the wafer flattened by the first grinding process as a reference surface / RTI &gt; Wherein the curable resin composition in the step (B) is at least one selected from the group consisting of polyester di (meth) acrylate, polyurethane di (meth) acrylate and epoxy di (meth) acrylate, (Meth) acrylic compound having at least two (meth) acrylic groups, (b) a hydrophilic (meth) acrylic compound having at least two (meth) acrylic groups in the molecule, and (c) a photopolymerization initiator. Gt; The method of manufacturing a wafer according to claim 1, wherein the curing shrinkage ratio (b1) of the curable resin composition is 5.8% or less. The method according to claim 1 or 2, wherein the step of forming the curable resin composition layer in the step (B) is a step of forming the wafer on the curable resin composition previously coated on the light- Way. The method for producing a wafer according to claim 1 or 2, wherein the viscosity of the curable resin composition in the step (B) at the time of uncuring is 1000 mPa · s to 50000 mPa · s. A curable resin composition for use in the method for producing a wafer according to any one of claims 1 to 3, (A) a (meth) acrylic compound selected from polyester di (meth) acrylate, polyurethane di (meth) acrylate and epoxy di (meth) acrylate and having at least a (meth) (B) a hydrophilic (meth) acrylic compound having at least two (meth) acrylic groups in the molecule, and (c) a photopolymerization initiator, And has the following characteristics (b1) and (b2). (b1) Curing shrinkage is not more than 7% (b2) the value at 25 ℃ 1.0 × 10 of the storage modulus (E ') of the cured body ⁶ ㎩~3.0 × 10 ⁹ Pa The curable resin composition according to claim 5, wherein the curing shrinkage ratio (b1) is 5.8% or less.

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