JP2014225662A - Photosensitive adhesive composition, and semiconductor device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide: a photosensitive adhesive composition which makes possible to glue semiconductor elements to each other while relaxing the concentration of stress; and a semiconductor device which includes a lamination type semiconductor element arranged by gluing semiconductor elements to each other with such a photosensitive adhesive composition and which is highly reliable and easy to manufacture.SOLUTION: A photosensitive adhesive composition is used between layers of a lamination type semiconductor element. The hardened material of the photosensitive adhesive composition has an elastic modulus of 2.0-3.5 GPa at 25°C. The elastic modulus which the photosensitive adhesive composition has at 25°C before being hardened is 70-120% of the elastic modulus of the hardened material at 25°C. The adhesive force which the composition before being hardened after having gone through an etching process and an ashing process exhibits to a semiconductor element at 25°C is 20-200 N. The minimum melt viscosity which the composition before being hardened has in a range of 100-200°C is 20-500 Pa s. In addition, a semiconductor device 10 comprises: semiconductor chips 20; and adhesion layers 601 each including the hardened material of the photosensitive adhesive composition of the invention.

Description

  The present invention relates to a photosensitive adhesive composition and a semiconductor device.

  The degree of integration of semiconductor devices has been increasing year by year in accordance with what is called Moore's law. However, in recent years, miniaturization of structures formed in semiconductor elements has approached physical limits, and the pace of high integration has slowed. In view of this, a method has been proposed in which the apparent integration degree is increased by stacking a plurality of semiconductor elements instead of increasing the density of one semiconductor element.

  When stacking semiconductor elements, an adhesive film for die bonding is disposed between the semiconductor elements, thereby bonding the elements. On the other hand, a buffer coat is provided between the semiconductor element and the adhesive in consideration of the generation of stress accompanying the curing shrinkage of the adhesive. Thereby, relaxation of stress concentration at the interface between the semiconductor element and the adhesive is achieved.

  In paragraphs 0003, 0078, and 0079 of Patent Document 1, in a stack package in which a plurality of semiconductor elements are stacked, a surface protective layer such as a buffer coat film is formed on a wafer, and this is bonded to a die bonding film (die attach film). Is disclosed.

  Recently, with the widespread use of mobile devices, there is an increasing demand for smaller and thinner semiconductor devices incorporated therein. Therefore, it is necessary to reduce the thickness of a semiconductor device in which a plurality of semiconductor elements are stacked. However, on the other hand, since there is a strong demand for further higher integration, it has been studied to increase the number of stacked semiconductor elements.

JP 2004-051970

  However, when a large number of semiconductor elements are stacked, two layers of a buffer coating film for protecting the surface of each semiconductor element and a die bonding film for bonding the semiconductor elements are interposed between the semiconductor elements. There is a limit to reducing the thickness of the entire semiconductor device. In addition, since the two layers are interposed, the stacking process becomes complicated, and the problem becomes more apparent as the number of stacked layers increases.

  Therefore, it is necessary to reduce the thickness of the entire semiconductor device and simplify the manufacturing process by reducing the number of members interposed between the semiconductor elements. However, since the element protection function of the buffer coat film and the bonding function of the die bonding film also include mutually contradicting elements, it is still insufficient to exert two functions in one layer.

  An object of the present invention is to provide a photosensitive adhesive composition capable of adhering semiconductor elements while relaxing stress concentration, and a laminated semiconductor element in which semiconductor elements are adhered to each other by such a photosensitive adhesive composition. An object of the present invention is to provide a semiconductor device that is highly producible and easy to manufacture.

Such an object is achieved by the present inventions (1) to (4) below.
(1) A photosensitive adhesive composition used between layers of a stacked semiconductor element,
The elastic modulus at 25 ° C. of the cured product is 2.0 to 3.5 GPa,
The elastic modulus at 25 ° C. before curing is 70 to 120% of the elastic modulus at 25 ° C. of the cured product,
The adhesive strength at 25 ° C. to the semiconductor element of the composition before curing subjected to etching treatment and ashing treatment is 20 to 200 N,
The photosensitive adhesive composition characterized by the minimum melt viscosity in 100-200 degreeC of the composition before hardening being 20-500 Pa.s.

(2) The pre-curing composition subjected to the etching treatment and the ashing treatment has an adhesive strength at 25 ° C. of 3.0 N / 25 mm or more with respect to the UV peeling type back grind film, and before the curing after the UV irradiation treatment. The photosensitive adhesive composition according to the above (1), wherein the adhesive strength of the composition at 50 ° C. to the back grind film is 0.5 N / 25 mm or less.
(3) The photosensitive adhesive composition as described in said (1) or (2) containing cyclic olefin resin.

  (4) It is provided with the laminated semiconductor element which laminates | stacks semiconductor elements through the hardened | cured material of the photosensitive adhesive composition of any one of said (1) thru | or (3). A featured semiconductor device.

ADVANTAGE OF THE INVENTION According to this invention, the photosensitive adhesive composition which can adhere | attach semiconductor elements can be obtained, relieving stress concentration.
In addition, according to the present invention, a highly reliable semiconductor device including a stacked semiconductor element can be obtained.

It is sectional drawing which shows embodiment of the semiconductor device of this invention. It is a figure for demonstrating the method to manufacture the semiconductor device of this invention. It is a figure for demonstrating the method to manufacture the semiconductor device of this invention. It is a figure for demonstrating the method to manufacture the semiconductor device of this invention.

Hereinafter, the photosensitive adhesive composition and semiconductor device of the present invention will be described in detail based on preferred embodiments shown in the accompanying drawings.
<Semiconductor device>
First, an embodiment of a semiconductor device of the present invention will be described.

FIG. 1 is a cross-sectional view showing an embodiment of a semiconductor device of the present invention.
A semiconductor device 10 shown in FIG. 1 is an example having a BGA (Ball Grid Array) type semiconductor package, and a plurality of stacked semiconductor chips (semiconductor elements) 20 and an adhesive layer 601 for bonding the semiconductor chips 20 to each other. The package substrate 30 that supports the semiconductor chip 20, the adhesive layer 101 that bonds the semiconductor chip 20 and the package substrate 30, the mold part 50 that seals the semiconductor chip 20, and the solder that is provided below the package substrate 30 And a ball 80. Hereinafter, the process of each part will be described in detail.

The semiconductor chip 20 may be any kind of element, such as a NAND flash memory, a memory element such as a DRAM, an integrated circuit element such as an IC or an LSI.

  The constituent material of the semiconductor chip 20 is not particularly limited, and examples thereof include single crystal materials such as silicon and silicon carbide, polycrystalline materials, and amorphous materials.

The plurality of semiconductor chips 20 are stacked slightly shifted from each other in the in-plane direction, thereby forming a chip stack 200. The semiconductor chips 20 are bonded to each other through an adhesive layer 601.
The adhesive layer 601 is also provided on the upper surface of the chip stack 200.

  A package substrate 30 shown in FIG. 1 is a build-up substrate including a core substrate 31, an insulating layer 32, a solder resist layer 33, a wiring 34, and a conductive via 35.

  Among these, the core substrate 31 is a substrate that supports the semiconductor device 10 and is made of, for example, a composite material in which a glass cloth is filled with a resin material.

  The insulating layer 32 is an interlayer insulating layer that insulates between the wirings 34 and between the wirings 34 and the conductive vias 35, and is made of, for example, a resin material. The solder resist layer 33 is a surface protective layer that protects the wiring formed on the outermost surface of the package substrate 30, and is made of, for example, a resin material.

  The wiring 34 and the conductive via 35 are each an electric signal transmission path, and are made of, for example, a metal material such as a simple substance or an alloy of Au, Ag, Cu, Al, and Ni.

  The solder ball 80 is electrically connected to the wiring 34, and functions as an electrode for connecting the wiring 34 to another electric circuit by being fused to an external electric circuit.

  A chip stack 200 formed by stacking a plurality of semiconductor chips 20 is placed on the upper surface of the package substrate 30. The chip stack 200 and the package substrate 30 are bonded by an adhesive layer 101.

  A part of the wiring 34 of the package substrate 30 is exposed on the upper surface of the package substrate 30, and the exposed portion and the electrode portion of each semiconductor chip 20 are connected by a bonding wire 70.

  The mold unit 50 shown in FIG. 1 is configured to cover the entire top surface of the package substrate 30 while covering the side surface and top surface of the chip stack 200. Thereby, the chip laminated body 200 can be protected from the external environment. Such a mold part 50 is comprised with various resin materials, such as an epoxy resin and a phenol resin, for example.

<Photosensitive adhesive composition>
Next, the photosensitive adhesive composition will be described.
≪Physical properties≫
The adhesive layer 601 for adhering the semiconductor chips 20 is composed of a cured product of the photosensitive adhesive composition of the present invention. Such an adhesive layer 601 is provided with sufficient adhesiveness and stress relaxation properties despite the single layer structure. Therefore, it is possible to obtain a highly reliable chip stack 200 in which stress concentration between layers caused by a difference in thermal expansion and the like is reduced while avoiding a significant increase in the total thickness of the chip stack 200. As a result, a low-profile and highly reliable semiconductor device 10 can be obtained. Such a semiconductor device 10 has a very small internal volume, such as a mobile device, and is particularly useful in an electronic device that is used while being carried. That is, it is useful in that it contributes to the reduction in size, thickness, and weight of the electronic device and that the function of the semiconductor device 10 is hardly impaired even when the electronic device is dropped or swung.

  The cured product of the photosensitive adhesive composition of the present invention, that is, the elastic modulus of the adhesive layer 601 is 2.0 to 3.5 GPa at 25 ° C. In addition, the elastic modulus of the photosensitive adhesive composition of the present invention before curing is set to 70 to 120% of the elastic modulus at 25 ° C. of the cured product at 25 ° C. Moreover, the adhesive force with respect to the semiconductor chip 20 of the photosensitive adhesive composition of this invention in the state before the hardening which performed the etching process and the ashing process shall be 20.0-200.0N in 25 degreeC.

  Such a photosensitive adhesive composition of the present invention has an elastic modulus in a state before curing within a predetermined range with respect to the elastic modulus after curing, for example, the photosensitive adhesive composition before curing. Is significantly deformed or flows out, so that the alignment accuracy when the semiconductor chip 20 is stacked can be increased. Furthermore, since the amount of change in elastic modulus before and after curing is relatively small, the amount of shrinkage associated with photosensitivity can also be reduced, and the stress generated at the interface with the semiconductor chip 20 due to curing shrinkage can be reduced. it can. From this viewpoint, it contributes to improving the reliability of the chip stack 200.

  On the other hand, the photosensitive adhesive composition of the present invention in a state before being subjected to etching treatment and ashing treatment has a sufficient adhesion force required for die bonding to the semiconductor chip 20. For this reason, the adhesive layer 601 that bonds the semiconductor chips 20 to each other securely fixes the semiconductor chips 20 to each other and contributes to improving the reliability of the chip stack 200.

  From the above, according to the photosensitive adhesive composition of the present invention, it is possible to realize the adhesive layer 601 that has both sufficient adhesiveness and stress relaxation properties. In other words, since the adhesive layer 601 combines the element protection function (buffer coating function) of the buffer coating film and the bonding function (die bonding function) of the die bonding film with one layer, the reliability is lowered. It is possible to form the chip stacked body 200 without reducing the thickness of the chip stacked body 200 as compared with the conventional structure using two layers. Further, as the chip stack 200 is made thinner, the volume of the mold part 50 can be reduced and the bonding wire 70 can be shortened, thereby contributing to weight reduction and cost reduction.

  In addition, the elastic modulus of the cured product of the photosensitive adhesive composition of the present invention is set to 2.0 to 3.5 GPa at 25 ° C. as described above, and preferably about 2.2 to 3.2 GPa. More preferably, it is about 2.4 to 3.0 GPa. In addition, when the elasticity modulus of hardened | cured material is less than the said lower limit, the adhesive force of the contact bonding layer 601 will fall, the interface with the semiconductor chip 20 will peel, or when the filler is contained in the mold part 50 In some cases, the filler penetrates the adhesive layer 601 and adversely affects the semiconductor chip 20. On the other hand, when the elastic modulus of the cured product exceeds the upper limit, the flexibility of the adhesive layer 601 is reduced, so that the stress relaxation property is reduced. For example, the residual stress generated due to the stacking of the semiconductor chips 20 or the semiconductor chip 20 is reduced. The local concentration of thermal stress due to the difference in thermal expansion between the semiconductor chip 20 and the adhesive layer 601 cannot be relaxed, causing cracks in the semiconductor chip 20 or peeling between the semiconductor chip 20 and the adhesive layer 601. .

  The elastic modulus of the cured product is, for example, a measurement temperature of 25 ° C., a load of 2 mN, a holding time of 1 second using an ultra-micro hardness meter ENT-1000 (manufactured by Elionix), and Berkovich indenter (triangular pyramid, opposite ridge angle 115 °), and can be obtained by measurement according to ISO14577.

Further, the elastic modulus of the photosensitive adhesive composition of the present invention before curing is set to 70 to 120% of the elastic modulus of the cured product at 25 ° C. as described above, and preferably 75 to 115%. And more preferably about 80 to 110%. In addition, when the elastic modulus in a state before curing is lower than the lower limit value, although the tackiness is increased, the film of the photosensitive adhesive composition is easily deformed. For example, the semiconductor chip 20 is temporarily disposed via the film. In this case, the position may be easily shifted, or the photosensitive adhesive composition may flow out. On the other hand, when the elasticity modulus in the state before hardening exceeds the said upper limit, adhesiveness falls and it becomes difficult to arrange | position the semiconductor chip 20 temporarily.
In addition, the elasticity modulus of the state before hardening can be measured similarly to the elasticity modulus of hardened | cured material.

  Furthermore, the adhesive force of the photosensitive adhesive composition of the present invention to the semiconductor chip 20 in the state before the etching treatment and the ashing treatment is 20 to 200 N as described above at 25 ° C., preferably Is about 30 to 180N, more preferably about 40 to 160N. In addition, when the adhesive force is less than the lower limit value, the reliability of the semiconductor device 10 is deteriorated, for example, by releasing the bonding between the semiconductor chips 20. On the other hand, when the adhesive strength exceeds the upper limit, structural problems do not occur, but no further increase in effect can be expected.

  Moreover, the adhesive force with respect to the semiconductor chip 20 is such that, after the semiconductor chips 20 are bonded to each other through the photosensitive adhesive composition of the present invention in the state before the etching process and the ashing process, the sample is Dage4000 ( It is calculated | required as intensity | strength (die shear intensity | strength) when it pushes in a horizontal direction with a shear tool using a shear tool, and the joining surface between chips | tips is fractured.

The etching process is a process of removing a passivation film on the surface of the semiconductor chip and exposing a pad for connecting a bonding wire. For example, fluorine compound gas (CF ₄ ) and argon gas (Ar ) And oxygen gas (O ₂ ), an output of 2500 W, a time of 6 minutes, and a CF ₄ flow rate / Ar flow rate / O ₂ flow rate of 200 sccm / 200 sccm / 50 sccm.

In addition, the ashing process is a process of removing processing residues and the like generated by the etching process and cleaning the adhesive layer surface and the pad surface. For example, a mixed gas of oxygen gas (O ₂ ) and Ar is used, An example of the plasma treatment is an output of 600 W, a time of 12 minutes, and an O ₂ flow rate / Ar flow rate of 50 sccm / 150 sccm.

  Such an etching process and an ashing process may promote deterioration of the organic material. Therefore, when the adhesive layer 601 has low etching process resistance and ashing process resistance, the semiconductor chips 20 may not be sufficiently bonded to each other. There is.

  On the other hand, since the adhesive layer 601 formed using the photosensitive adhesive composition of the present invention has sufficient etching processing resistance and ashing processing resistance, such etching processing and ashing processing are performed. Even after passing, a decrease in the adhesive strength is suppressed, and as a result, the adhesive strength as described above is exhibited. Therefore, since the photosensitive adhesive composition of the present invention does not need to consider a decrease in adhesiveness in various processes in the semiconductor manufacturing process, the manufacturing process can be simplified and the cost can be easily reduced. It is useful in that respect.

The photosensitive adhesive composition of the present invention has a minimum melt viscosity of 20 to 500 Pa · s in the range of 100 to 200 ° C. in the cured state. Since such a composition is excellent in wettability with respect to the semiconductor chip 20, it becomes difficult for voids or the like to be generated in the adhesive layer 601. Accordingly, since a uniform adhesive layer 601 with little variation in physical properties can be formed, when the semiconductor chips 20 are bonded to each other via the adhesive layer 601, it is difficult to cause local concentration of stress, and cracks are generated in the semiconductor chip 20. In addition, the occurrence of peeling between the semiconductor chip 20 and the adhesive layer 601 can be suppressed. In addition, the melt viscosity after hardening of the photosensitive adhesive composition of this invention can be measured with a rheometer.
The minimum melt viscosity after curing is preferably 25 to 400 Pa · s, more preferably 30 to 300 Pa · s.

  In addition, the photosensitive adhesive composition of the present invention has a certain level of tackiness when it is in its pre-cured state, while reducing its tackiness by subjecting it to UV irradiation treatment. be able to. Therefore, it can be said that the tackiness of the photosensitive adhesive composition of the present invention can be controlled by the presence or absence of UV irradiation treatment.

Specifically, the photosensitive adhesive composition of the present invention is in a state before being cured, and after being subjected to the etching process and the ashing process described above, the UV peeling type back grind film is used. Preferably, it exhibits an adhesive strength of 3.0 N / 25 mm or more at 25 ° C. Such a photosensitive adhesive composition of the present invention can exhibit a sufficient adhesive force to the back grind film even after performing a treatment that promotes deterioration of the organic material such as an etching treatment or an ashing treatment. Therefore, for example, when a dicing process is performed on a semiconductor wafer on which a coating film of the photosensitive adhesive composition of the present invention is formed, the semiconductor wafer can be securely fixed, so that the dicing accuracy can be further improved. it can.
The adhesive strength is more preferably 3.5 N / 25 mm or more and 10.0 N / 25 mm or less.

  The adhesive strength was bonded so that the adhesive surface of the UV peeling type back grind film (width 25 mm, length 75 mm) was in contact with the coating film of the photosensitive adhesive composition of the present invention, and the measurement temperature was 25 ° C. The peeling rate is 10.0 ± 0.2 mm / s, and the back grind is applied from the coating film of the photosensitive adhesive composition of the present invention so that the peeling angle is 180 ° from one end in the longitudinal direction of the back grind film. It can be determined by peeling the film and measuring the average value of the load required for peeling (180 ° peeling adhesive strength, unit: N / 25 mm, JIS Z 0237 compliant).

  On the other hand, the photosensitive adhesive composition of the present invention is in a state before being cured and after being subjected to the UV irradiation treatment, preferably at 50 ° C. with respect to the UV peeling type back grind film. It exhibits an adhesive strength of 0.5 N / 25 mm or less. Such a photosensitive adhesive composition of the present invention can sufficiently reduce the adhesive strength to the back grind film by UV irradiation treatment. For example, when picking up individualized chips after dicing treatment, In addition, the separability between the back grind film and the coating film is improved, and it is possible to prevent the occurrence of defects such as chipping.

Further, by reducing the adhesive force, for example, the photosensitive adhesive composition of the present invention adheres to the dicing blade in the dicing process, or the photosensitive adhesive composition of the present invention adheres to the collet in the mounting process. Can be suppressed. As a result, it is possible to suppress the occurrence of dicing failure and pickup failure.
The adhesive strength is more preferably 0.05 N / 25 mm or more and 0.40 N / 25 mm or less.

In addition, the UV irradiation process is a process of irradiating light having a wavelength of 365 nm so that the integrated light amount is 600 mJ / cm ² .
The UV peeling type back grind film used in the above regulations is made of an acrylic resin.

≪Composition≫
The photosensitive adhesive composition comprises (A) a cyclic olefin resin containing a repeating unit having an acidic group, (B) a photoacid generator, (C) an aliphatic epoxy compound, and (D) a hydroxyl group equivalent of 60. And a phenol compound that is 150 g / eq.

Hereinafter, each material constituting the photosensitive adhesive composition will be described in detail.
<(A) Cyclic Olefin Resin Containing Repeating Unit Having Acid Group>
Examples of the (A) cyclic olefin resin containing a repeating unit having an acidic group (hereinafter sometimes simply referred to as “(A) cyclic olefin resin”) include norbornene resins and benzocyclobutene resins. Among these, norbornene-based resins are preferable. Since the norbornene-based resin is excellent in adhesiveness, the adhesive layer 601 includes the norbornene-based resin, so that the bonding strength between the semiconductor chips 20 is excellent.

In addition, since the norbornene-based resin has high hydrophobicity, it is possible to form the adhesive layer 601 that hardly causes a dimensional change due to water absorption.
In addition, (A) the cyclic olefin-based resin has at least one repeating unit having an acidic group (first repeating unit). The first repeating unit is a structure in which a substituent having an acidic group is bonded to a structure derived from a cyclic olefin (cyclic olefin monomer) as a main skeleton.

  As structures derived from cyclic olefins, monocyclic compounds such as cyclohexene and cyclooctene, norbornene, norbornadiene, dicyclopentadiene, dihydrodicyclopentadiene, tetracyclododecene, tricyclopentadiene, dihydrotricyclopentadiene, tetracyclopentadiene, Examples include structures derived from polycyclic compounds such as dihydrotetracyclopentadiene, and among these, a structure derived from norbornene is particularly preferable from the viewpoints of heat resistance and flexibility after curing.

Examples of the substituent having an acidic group include a substituent having a carboxyl group, a phenolic hydroxyl group, —C (OH) — (CF ₃ ) ₂ , —N (H) —S (O) ₂ —CF _{3, and the} like. Among these, a substituent having any of a carboxyl group and —C (OH) — (CF ₃ ) ₂ is preferable. (A) When cyclic olefin resin contains the substituent which has such an acidic group, the solubility with respect to an alkali developing solution can be improved. For this reason, development with an alkaline developer during manufacture of the semiconductor device becomes possible.

  For this reason, the first repeating unit is particularly preferably at least one selected from the group consisting of formula (2) and formula (3). By including the repeating unit having such a structure, the adhesive layer 601 has excellent adhesion to the semiconductor chip 20 and can be developed with an alkaline developer.

  In the formulas (2) and (3), x and y are each preferably an integer of 0 or more and 10 or less, and particularly preferably an integer of 1 or more and 5 or less. Thereby, it is possible to obtain the adhesive layer 601 that is superior in the bonding strength between the semiconductor chips 20.

  Moreover, (A) cyclic olefin resin should just have a repeating unit (1st repeating unit) which has an at least 1 sort (s) of acidic group, but has a repeating unit which has 2 or more types of different acidic groups. It is preferable. As a result, it is possible to obtain an adhesive layer 601 that can be developed with an alkali developer and that can more reliably fix the semiconductor chip 20.

  (A) Although the content rate of the repeating unit which has an acidic group in cyclic olefin resin can determine an optimal value by whether it can express alkali solubility after exposure, it is 10-80 mol%, for example. Is preferable, and it is more preferable that it is 20-70 mol%. When the content of the first repeating unit is less than the lower limit, it may be difficult to sufficiently develop solubility in an alkaline developer. When the content rate of the first repeating unit exceeds the upper limit, depending on the type of the first repeating unit, there is a possibility that the characteristics of other materials other than the (A) cyclic olefin resin are buried.

  (A) It is preferable that the acidic group in cyclic olefin resin is 0.2-0.1 mol per 1g of polymers. It is more preferable that it is 0.03-0.1 mol. As a result, the above-described effect of developing the solubility in the alkali developer can be remarkably exhibited.

  (A) It is preferable that cyclic olefin resin further has a 2nd repeating unit different from the 1st repeating unit which has the said acidic group.

  As the second repeating unit, a substituent different from the substituent of the first repeating unit is bonded to the structure derived from the cyclic olefin as the main skeleton.

  As the main skeleton of the second repeating unit, those mentioned in the first repeating unit described above can be used, and among these, particularly derived from norbornene from the viewpoints of heat resistance and flexibility after curing. A structure is preferred.

  The main skeletons of the first and second repeating units may be different from each other, but are preferably the same. In particular, the main skeletons of the first and second repeating units are preferably structures derived from norbornene. Thereby, the stress concentration generated at the bonding interface between the semiconductor chips 20 can be further relaxed, and the adhesive layer 601 that is particularly excellent in the bonding strength between the semiconductor chips 20 can be obtained.

  As a substituent which a 2nd repeating unit has, it is preferable that it is C2-C30, and it is more preferable that it is a C4-C15 linear substituent. When the carbon number is within the above range, the elastic modulus after curing of the photosensitive adhesive composition can be made moderate. Therefore, the adhesive layer 601 has moderate flexibility, and can suppress occurrence of cracks and peeling due to stress concentration, damage due to external impact, and the like.

  Moreover, although a cyclic structure, a branched structure, etc. may be sufficient, it is preferable that it is a linear structure. Thereby, the elasticity modulus after hardening of a photosensitive adhesive composition can be made moderate.

  Examples of the linear substituent having 2 to 30 carbon atoms include an alkyl group, an alkenyl group, an alkynyl group, an aryl group, an aralkyl group, and a group having an alkyl ether structure. It is preferable that it is group which has. Thereby, the photosensitive adhesive composition has excellent solubility in an alkaline aqueous solution and excellent flexibility after curing.

  The group having an alkyl ether structure is particularly preferably one represented by the formula (1). As a result, it is possible to obtain an adhesive layer 601 that is particularly excellent in solubility in an alkaline aqueous solution and that has appropriate flexibility.

  In Formula (1), z is preferably an integer of 1 or more and 10 or less, and more preferably an integer of 2 or more and 6 or less. Thereby, while being excellent in the solubility to alkaline aqueous solution, the adhesive layer 601 which has moderate softness | flexibility can be obtained more reliably.

  For this reason, the second repeating unit is particularly preferably the formula (4). By having a repeating unit of such a structure, in addition to the function that the solubility in an alkaline aqueous solution by the first repeating unit can be sufficiently expressed, the elastic modulus after curing of the photosensitive adhesive composition It is possible to achieve a balance with the function of making the thickness moderate. For this reason, the adhesive layer 601 is suppressed from being damaged by an external impact.

In particular, in Formula (4), z is preferably an integer of 1 or more and 10 or less, and more preferably an integer of 2 or more and 5 or less. Thereby, the elasticity modulus after hardening of a photosensitive adhesive composition can be made moderate. Therefore, the adhesive layer 601 has moderate flexibility, and the adhesive layer 601 can be formed in which cracks and peeling due to stress concentration, damage due to external impact, and the like hardly occur.

  In addition, the content of the second repeating unit in the (A) cyclic olefin-based resin is, for example, preferably 20 to 60 mol%, and more preferably 25 to 50 mol%. If the content of the first repeating unit is less than the lower limit, it may be difficult to adjust the elastic modulus after curing of the photosensitive adhesive composition depending on the type of the second repeating unit. Moreover, when the content rate of a 1st repeating unit exceeds the said upper limit, depending on the kind of 2nd repeating unit, when it becomes difficult to juxtapose with the characteristic of other materials other than (A) cyclic olefin resin There is.

  From the above, as the (A) cyclic olefin resin, those represented by the following formula (5) are suitable.

  In formula (5), l, m, and n are integers of 1 or more. As described above, x is preferably an integer of 0 or more and 10 or less, y is preferably an integer of 0 or more and 10 or less, and z is an integer of 1 or more and 10 or less. preferable.

  In the formula (5), the degree of polymerization of the repeating unit having the group containing an alkyl ether structure (second repeating unit) relative to the degree of polymerization of the repeating unit having acidic group (first repeating unit) (ie, (l + m) / N) is preferably 0.3 to 2.0, more preferably 0.4 to 1.5. As a result, it is possible to obtain an adhesive layer 601 that can alleviate the concentration of stress generated at the bonding interface between the semiconductor chips 20 and at the same time make the adhesive strength between the semiconductor chips 20 appropriate.

  The weight average molecular weight of the (A) cyclic olefin resin is preferably 5,000 to 500,000, more preferably 7,000 to 200,000, and 8,000 to 100,000. Is more preferable. Thereby, the adhesive layer 601 provided with sufficient adhesiveness can be obtained.

Here, a weight average molecular weight can be measured using gel permeation chromatography (GPC) using standard polynorbornene (ASTMDS 3536-91 conformity).
Moreover, such (A) cyclic olefin resin is obtained by polymerizing a cyclic olefin monomer.

For example, as a polymerization method of norbornene-based resin, it can be produced by a known polymerization method, and there are an addition polymerization method and a ring-opening polymerization method. Among these, addition polymers obtained by the addition polymerization method include (1) addition (co) polymers of norbornene monomers obtained by addition (co) polymerization of norbornene monomers, and (2) norbornene monomers. -Addition copolymers of-with ethylene or α-olefins, (3) addition copolymers of norbornene-type monomers and non-conjugated dienes, and other monomers as required. Addition (co) polymers are also preferred because they are rich in transparency, heat resistance and flexibility.

  The ring-opening polymer obtained by the ring-opening polymerization method includes (4) a ring-opening (co) polymer of a norbornene-type monomer, and a resin obtained by hydrogenating the (co) polymer, if necessary, (5) a ring-opening copolymer of a norbornene-type monomer and ethylene or α-olefins, and a resin obtained by hydrogenating the (co) polymer if necessary, (6) a norbornene-type monomer and a non-conjugated diene Or a ring-opening copolymer with another monomer, and a resin obtained by hydrogenating the (co) polymer if necessary.

  Among the above, (1) addition (co) polymer obtained by addition (co) polymerization of norbornene type monomer, (4) ring-opening (co) polymer of norbornene type monomer, and A resin obtained by hydrogenating a (co) polymer is preferred.

  Examples of the monomer for obtaining the (A) cyclic olefin resin by such a polymerization method include, for example, monocyclic compounds such as cyclohexene and cyclooctene, norbornene, norbornadiene, dicyclopentadiene, dihydrodicyclopentadiene, and tetracyclododecene. , Tricyclopentadiene, dihydrotricyclopentadiene, tetracyclopentadiene, dihydrotetracyclopentadiene and the like having a substituent bonded thereto. Among these, the norbornene type monomer represented by the formula (6) is particularly preferable.

[In Formula (6), n is an integer of 0-5. R ^{1 to} R ⁴ are each a hydrogen, an alkyl group, an alkenyl group, an alkynyl group, an aryl group, an aralkyl group, a substituent having an alkyl ether structure, a substituent containing an ester group, a substituent containing a ketone group, Of an ether group-containing substituent, a carboxyl group, a phenolic hydroxyl group, a group containing an acidic group such as —C (OH) — (CF ₃ ) ₂ , —N (H) —S (O) ₂ —CF ₃ Any of them may be used. R ^{1 to} R ⁴ may be different among repeating monomers, but at least one of R ^{1 to} R ⁴ of all repeating units has an acidic group. ]

Specific examples of the alkyl group in the formula (6) include methyl, ethyl, propyl, isopropyl, butyl, pentyl, hexyl, heptyl, octyl, nonyl, decyl, dodecyl, cyclopentyl, cyclohexyl, cyclooctyl group and the like. Specific examples include vinyl, allyl, butynyl, cyclohexenyl groups, etc. Specific examples of alkynyl groups include ethynyl, 1-propynyl, 2-propynyl, 1-butynyl, 2-butynyl groups, etc. Examples include phenyl, naphthyl, anthracenyl groups, aralkyl groups such as benzyl and phenethyl groups, and groups containing acidic groups include carboxyl groups, phenolic hydroxyl groups, -C (OH)-( _{CF 3) 2, -N (H} ) -S (O) 2
-CF ₃ can be mentioned.

  In addition, as for the substituent containing an ester group and the substituent containing a ketone group, the structure is not particularly limited as long as it is a substituent having these groups. The substituent containing an ether group includes a functional group containing a cyclic ether such as an epoxy group or an oxetane group.

  The group having an alkyl ether structure is not particularly limited as long as it is a substituent having an alkyl ether structure, but a group having a group represented by the following formula (1) is preferable.

Moreover, the addition polymer of cyclic olefin resin is obtained by coordination polymerization by a metal catalyst, or radical polymerization. Among these, in coordination polymerization, a polymer is obtained by polymerizing a monomer in a solution in the presence of a transition metal catalyst (NiCOLE R. GROVE).
et al. Journal of Polymer Science: part B, P
polymer Physics, Vol. 37, 3003-3010 (1999)).

  Representative nickel and platinum catalysts as metal catalysts for coordination polymerization are described in PCT WO 9733198 and PCT WO 00/20472. Examples of metal catalysts for coordination polymerization include (toluene) bis (perfluorophenyl) nickel, (mesylene) bis (perfluorophenyl) nickel, (benzene) bis (perfluorophenyl) nickel, bis (tetrahydro) bis ( Known metal catalysts such as perfluorophenyl) nickel, bis (ethyl acetate) bis (perfluorophenyl) nickel, and bis (dioxane) bis (perfluorophenyl) nickel may be mentioned.

The radical polymerization technique is described in Encyclopedia of Polymer Science, John Wiley & Sons, 13, 708 (1988).
Generally, in radical polymerization, the temperature is raised to 50 ° C. to 150 ° C. in the presence of a radical initiator, and the monomer is reacted in a solution. Examples of the radical initiator include azobisisobutyronitrile (AIBN), benzoyl peroxide, lauryl peroxide, azobisisocapronitrile, azobisisoleronitrile, and t-butyl hydrogen peroxide.

  A ring-opening polymer of a cyclic olefin resin is obtained by ring-opening (co) polymerization of at least one norbornene-type monomer by a known ring-opening polymerization method using titanium or a tungsten compound as a catalyst. Obtained by producing a thermoplastic saturated norbornene-based resin by hydrogenating the carbon-carbon double bond in the ring-opening (co) polymer by a conventional hydrogenation method, if necessary. .

Moreover, (A) cyclic olefin resin is obtained by superposing | polymerizing the monomer which has an acidic group by the said method directly. However, depending on the polymerization system, if the monomer contains an acidic group, the catalyst or the like may be deactivated and the polymerization may not proceed appropriately. In this case, a cyclic olefin-based resin having an acidic group can be obtained by introducing a protective group into the acidic group, polymerizing, and deprotecting the polymer after production. Alternatively, a method may be adopted in which a functional group capable of chemically reacting with an acidic group is introduced into the monomer, and the functional group is converted into an acidic group by polymer reaction after polymer synthesis.

  As described above, the cyclic olefin-based resin (A) is a monomer obtained by substituting an ionizable hydrogen atom of an acidic group in a cyclic olefin monomer with another structure, polymerizing this, and then deprotecting the original. It can obtain by introduce | transducing the hydrogen atom of. Specific examples of functional groups that can be substituted with hydrogen atoms at this time include tertiary butyl groups, tertiary butoxycarbonyl groups, tetrahydropyran-2-yl groups, trialkylsilyl groups such as trimethylsilyl groups, and methoxymethyl groups. And so on. Deprotection, that is, restoration of the acidic group by elimination of the protecting group from the monomer can be performed by a conventional method in the case of using the functional group as a protective group for the acidic functional group.

A method for obtaining (A) a cyclic olefin-based resin by polymerizing a cyclic olefin-based resin having no acidic group to introduce an acidic group will be described. In the presence of a radical initiator, a cyclic olefin resin having no acidic group is converted into acrylic acid, methacrylic acid, α-ethylacrylic acid, 2-hydroxyethyl (meth) acrylic acid, maleic acid, fumaric acid, itaconic acid, endocis. Unsaturation such as -bicyclo [2.2.1] hept-5-ene-2,3-dicarboxylic acid, methyl-endocis-bicyclo [2.2.1] hept-5-ene-2,3-dicarboxylic acid Mixed with polar group-containing compounds such as carboxylic acid compounds, or esters or amides thereof, or unsaturated carboxylic acid anhydrides such as maleic anhydride, chloromaleic anhydride, butenyl succinic anhydride, tetrahydrophthalic anhydride, citraconic anhydride, etc. Then, (A) a cyclic olefin resin can be obtained by heating.
(A) As a monomer for obtaining cyclic olefin resin, what was described in Unexamined-Japanese-Patent No. 2007-78820 can be used, for example.

Among monomers for obtaining a cyclic olefin-based resin having an acidic group, a monomer having an acidic group or a monomer having a functional group that becomes an acidic group by deprotection is specifically bicyclo [2.2.1. ] Hept-2-ene-5-carboxylic acid, tetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] dodec-3-ene-8-carboxylic acid, 8-methyltetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] dodec-3-ene-8-carboxylic acid, (bicyclo [2.2.1] hept-2-en-5-yl) acetic acid, 2- (bicyclo [2.2.1] hept- 2-ene-5-yl) propionic acid, 3- (bicyclo [2.2.1] hept-2-en-5-yl) butyric acid, 3- (bicyclo [2.2.1] hept-2-ene -5-yl) valeric acid, 3- (bicyclo [2.2.1] hept-2-en-5-yl) caproic acid, succinic acid mono- (2- (bicyclo [2.2.1] hept- 2-ene-5-yl) carbonyloxyethyl) ester, succinic acid mono- (2- (bicyclo [2.2.1] hept-2-en-5-yl) carbonyloxypropyl) ester, succinic acid mono- (2- (Bicyclo [2.2.1] hept-2-en-5-yl) carboni Oxybutyl) ester, mono- (2- (bicyclo [2.2.1] hept-2-en-5-yl) carbonyloxyethyl) ester phthalate, caproic acid mono- (2- (bicyclo [2.2. 1) hept-2-en-5-yl) carbonyloxybutyl) ester, (bicyclo [2.2.1] hept-2-en-5-yl) carbonyloxyacetic acid, 2- (bicyclo [2.2. 1] hept-2-en-5-yl) methylphenol, 3- (bicyclo [2.2.1] hept-2-en-5-yl) methylphenol, 4- (bicyclo [2.2.1] Hept-2-en-5-yl) methylphenol, 4- (bicyclo [2.2.1] hept-2-en-5-yl) phenol, 4- (bicyclo [2.2.1] hept-2 -En-5-yl) methylca Tecor, 3-methoxy-4- (bicyclo [2.2.1] hept-2-en-5-yl) methylphenol, 3-methoxy-2- (bicyclo [2.2.1] hept-2-ene -5-yl) methylphenol, 2- (bicyclo [2.2.1] hept-2-en-5-yl) methylresorcin, 1,1-bistrifluoromethyl-2- (bicyclo [2.2.1] ] Hept-2-en-5-yl) ethyl alcohol, 1,1-bistrifluoromethyl-3- (bicyclo [2.2.1] hept-2-en-5-yl) propyl alcohol, 1,1- Bistrifluoromethyl-4- (bicyclo [2.2.1] hept-2-en-5-yl) butyl alcohol, 1,1-bistrifluoromethyl-5- (bicyclo [2.2.1] hept-2 -En-5-yl Pentyl alcohol, 1,1-bis-trifluoromethyl-6- (bicyclo [2.2.1] hept-2-ene-5-yl) hexyl alcohol, 8 methoxycarbonyltetracyclo [4.4.0.1 ^{2 , 5} . 1 ^7,10 ] dodec-3-ene, 8-ethoxycarbonyltetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] dodec-3-ene, 8-n-propylcarbonyltetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] dodec-3-ene, 8-i-propylcarbonyltetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] dodec-3-ene, 8-n-butoxycarbonyltetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] dodec-3-ene, 8- (2-methylpropoxy) carbonyltetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] dodec-3-ene, 8- (1-methylpropoxy) carbonyltetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] dodec-3-ene, 8-t-butoxycarbonyltetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] dodec-3-ene, 8-cyclohexyloxycarbonyltetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] dodec-3-ene, 8- (4′-t-butylcyclohexyloxy) carbonyltetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] dodec-3-ene, 8-phenoxycarbonyltetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] dodec-3-ene, 8-tetrahydrofuranyloxycarbonyltetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] -3-dodecene, 8-tetrahydropyranyloxycarbonyltetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] dodec-3-ene, 8-methyl-8-methoxycarbonyltetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] dodec-3-ene, 8-methyl-8-ethoxycarbonyltetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] dodec-3-ene, 8-methyl-8-n-propoxycarbonyltetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] dodec-3-ene, 8-methyl-8-i-propoxycarbonyltetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] dodec-3-ene, 8-methyl-8-n-butoxycarbonyltetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] dodec-3-ene, 8-methyl-8- (2-methylpropoxy) carbonyltetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] dodec-3-ene, 8-methyl-8- (1-methylpropoxy) carbonyltetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] dodec-3-ene, 8-methyl-8-t-butoxycarbonyltetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] dodec-3-ene, 8-methyl-8-cyclohexyloxycarbonyltetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] dodec-3-ene, 8-methyl-8- (4′-t-butylcyclohexyloxy) carbonyltetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] dodec-3-ene, 8-methyl-8-phenoxycarbonyltetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] dodec-3-ene, 8-methyl-8-tetrahydrofuranyloxycarbonyltetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] dodec-3-ene, 8-methyl-8-tetrahydropyranyloxycarbonyltetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] -3-dodecene, 8-methyl-8-acetoxytetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] dodec-3-ene, 8,9-di (methoxycarbonyl) tetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] dodec-3-ene, 8,9-di (ethoxycarbonyl) tetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] dodec-3-ene, 8,9-di (n-propoxycarbonyl) tetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] dodec-3-ene, 8,9-di (i-propoxycarbonyl) tetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] dodec-3-ene, 8,9-di (n-butoxycarbonyl) tetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] dodec-3-ene, 8,9-di (t-butoxycarbonyl) tetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] dodec-3-ene, 8,9-di (cyclohexyloxycarbonyl) tetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] dodec-3-ene, 8,9-di (phenoxyloxycarbonyl) tetracyclo [4
. 4.0.1 ^2,5 . 1 ^7,10 ] dodec-3-ene, 8,9-di (tetrahydrofuranyloxycarbonyl) tetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] -3-dodecene, 8,9-di (tetrahydropyranyloxycarbonyl) tetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] -3-dodecene, tetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] dodec-3-ene-8-carboxylic acid, 8-methyltetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] dodec-3-ene-8-carboxylic acid, and the like, but are not limited to these in the present invention.

Among monomers for obtaining a cyclic olefin-based resin having an acidic group, specific examples of monomers other than those described above include the following. As those having an alkyl group, 5-methyl-2-norbornene, 5-ethyl-2-norbornene, 5-propyl-2-norbornene, 5-butyl-2-norbornene, 5-pentyl-2-norbornene, 5-hexyl As those having an alkenyl group, such as 2-norbornene, 5-heptyl-2-norbornene, 5-octyl-2-norbornene, 5-nonyl-2-norbornene, 5-decyl-2-norbornene, 5-allyl- 2-norbornene, 5-methylidene-2-norbornene, 5-ethylidene-2-norbornene, 5-isopropylidene-2-norbornene, 5- (2-propenyl) -2-norbornene, 5- (3-butenyl) -2 -Norbornene, 5- (1-methyl-2-propenyl) -2-norbornene, 5- (4-pen Nyl) -2-norbornene, 5- (1-methyl-3-butenyl) -2-norbornene, 5- (5-hexenyl) -2-norbornene, 5- (1-methyl-4-pentenyl) -2-norbornene 5- (2,3-dimethyl-3-butenyl) -2-norbornene, 5- (2-ethyl-3-butenyl) -2-norbornene, 5- (3,4-dimethyl-4-pentenyl) -2 -Norbornene, 5- (7-octenyl) -2-norbornene, 5- (2-methyl-6-heptenyl) -2-norbornene, 5- (1,2-dimethyl-5-hexenyl) -2-norbornene, 5 Examples of those having an alkynyl group such as-(5-ethyl-5-hexenyl) -2-norbornene and 5- (1,2,3-trimethyl-4-pentenyl) -2-norbornene include 5- Nyl-2-norbornene and the like having an alkoxysilyl group include dimethylbis ((5-norbornen-2-yl) methoxy)) silane and the like having a silyl group such as 1,1,3,3, Examples of those having an aryl group such as 5,5-hexamethyl-1,5-dimethylbis ((2- (5-norbornen-2-yl) ethyl) trisiloxane) include 5-phenyl-2-norbornene, 5-naphthyl- Examples of those having an aralkyl group such as 2-norbornene and 5-pentafluorophenyl-2-norbornene include 5-benzyl-2-norbornene, 5-phenethyl-2-norbornene, 5-pentafluorophenylmethane-2-norbornene, 5- (2-pentafluorophenylethyl) -2-norbornene, 5- (3-pentaph Examples of those having an alkoxysilyl group such as urophenylpropyl) -2-norbornene include 5-trimethoxysilyl-2-norbornene, 5-triethoxysilyl-2-norbornene, and 5- (2-trimethoxysilylethyl). 2-norbornene, 5- (2-triethoxysilylethyl) -2-norbornene, 5- (3-trimethoxypropyl) -2-norbornene, 5- (4-trimethoxybutyl) -2-norbornene, 5- Examples of those having a hydroxyl group, an ether group, an ester group, an acryloyl group or a methacryloyl group, such as trimethylsilylmethyl ether-2-norbornene, include 5-norbornene-2-methanol and this alkyl ether, 5-norbornene-2-methyl acetate Ester, propionic acid 5-norvo Nene-2-methyl ester, butyric acid 5-norbornene-2-methyl ester, valeric acid 5-norbornene-2-methyl ester, caproic acid 5-norbornene-2-methyl ester, caprylic acid 5-norbornene-2-methyl ester, Capric acid 5-norbornene-2-methyl ester, lauric acid 5-norbornene-2-methyl ester, stearic acid 5-norbornene-2-methyl ester, oleic acid 5-norbornene-2-methyl ester, linolenic acid 5-norbornene- 2-methyl ester, 5-norbornene-2-carboxylic acid, 5-norbornene-2-carboxylic acid methyl ester, 5-norbornene-2-carboxylic acid ethyl ester, 5-norbornene-2-carboxylic acid t-butyl ester, 5 -Norbornene-2-carboxylic acid -Butyl ester, 5-norbornene-2-carboxylic acid trimethylsilyl ester, 5-norbornene-2-carboxylic acid triethylsilyl ester, 5-norbornene-2-carboxylic acid isobornyl ester, 5-norbornene-2-carboxylic acid 2-hydroxy Ethyl ester, 5-norbornene-2-methyl-2-carboxylic acid methyl ester, cinnamic acid 5-norbornene-2-methyl ester, 5-norbornene-2-methylethyl carbonate, 5-norbornene-2-methyl n- Butyl carbonate, 5-norbornene-2-methyl t-butyl carbonate, 5-methoxy-2-norbornene, (meth) acrylic acid 5-norbornene-2-methyl ester, (meth) acrylic acid 5-norbornene-2- Ethyl ester, (meth) acrylic Acid 5-norbornene-2-n-butyl ester, (meth) acrylic acid 5-norbornene-2-n-propyl ester, (meth) acrylic acid 5-norbornene-2-i-butyl ester, (meth) acrylic acid 5 -Norbornene-2-i-propyl ester, (meth) acrylic acid 5-norbornene-2-hexyl ester, (meth) acrylic acid 5-norbornene-2-octyl ester, (meth) acrylic acid 5-norbornene-2-decyl ester Examples of those having an epoxy group such as esters include 5-[(2,3-epoxypropoxy) methyl] -2-norbornene, and those consisting of a tetracyclo ring include 8,9-tetracyclo [4.4.0. 1 ^2,5 . 1 ^7,10 ] dodec-3-ene, 8-methyltetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] dodec-3-ene, 8-ethyltetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] dodec-3-ene, 8-methyltetracyclo [4.4.0.1 ^2,5 . 0 ^1,6 ] dodec-3-ene, 8-ethylidenetetracyclo [4.4.0.1 ^2,5 . 1 ^7,12] Dodekku-3-ene, 8-ethylidene tetracyclo [4.4.0.1 ^{2, 5.} 1 ^7,10 0 ^1,6 ] dodec-3-ene. However, the present invention is not limited to these.

  Suitable polymerization solvents for the above-described polymerization system include hydrocarbons and aromatic solvents. Examples of the hydrocarbon solvent include pentane, hexane, heptane, and cyclohexane, but are not limited thereto. Examples of the aromatic solvent include, but are not limited to, benzene, toluene, xylene and mesitylene. Diethyl ether, tetrahydrofuran, ethyl acetate, ester, lactone, ketone, amide can also be used. These solvents can be used alone or as a polymerization solvent.

  The molecular weight of the cyclic olefin resin can be controlled by changing the ratio of the initiator and the monomer or changing the polymerization time. When the above-mentioned coordination polymerization is used, US Pat. As disclosed in US Pat. No. 6,136,499, the molecular weight can be controlled by using a chain transfer catalyst. In the present invention, α-olefin such as ethylene, propylene, 1-hexane, 1-decene and 4-methyl-1-pentene is suitable for controlling the molecular weight.

  Further, as the cyclic olefin resin, those having a glass transition temperature of 100 to 250 ° C. are preferably used. By using the cyclic olefin resin having such a glass transition temperature, the heat resistance of the photosensitive adhesive composition is further increased, and the reliability of the semiconductor device 10 at a high temperature can be further increased.

  In addition, the glass transition temperature of cyclic olefin resin can be calculated | required as temperature which an exothermic reaction produces, when it heats up from normal temperature by the temperature increase rate of 5 degree-C / min, for example by the differential scanning calorimetry.

<(B) Photoacid generator>
The (B) photoacid generator can promote the reaction of crosslinking the (A) cyclic olefin resin by the (C) aliphatic epoxy compound described later by irradiation with energy rays. In addition, (B) a photoacid generator functions as a positive photoacid generator that generates a carboxyl group by a photoreaction during exposure by irradiation with actinic rays and increases the solubility of an exposed portion in an alkaline developer. Have

  (B) Examples of photoacid generators include onium salts, halogenated organic compounds, quinonediazide compounds, α, α-bis (sulfonyl) diazomethane compounds, α-carbonyl-α-sulfonyl-diazomethane compounds, sulfone compounds, and organic compounds. An acid ester compound, an organic acid amide compound, an organic acid imide compound, etc. are mentioned, Among these, it can use 1 type or in combination of 2 or more types. Among these, those having a quinonediazide compound are particularly preferable.

  Examples of the quinonediazide compound include a compound having a 1,2-benzoquinonediazide or a 1,2-naphthoquinonediazide structure. These are known substances from U.S. Pat. Nos. 2,729,975, 2,797,213 and 3,669,658. More preferably, it is an ester compound of 1,2-naphthoquinone-2-diazide-5-sulfonic acid or 1,2-naphthoquinone-2-diazide-4-sulfonic acid and a phenol compound. These function as a positive photoacid generator that generates a carboxyl group by a photoreaction during exposure by radiation irradiation and increases the solubility of the exposed portion in an alkaline developer. For this reason, a high solubility contrast can be obtained with a particularly small exposure amount.

  (B) Although content of a photo-acid generator is not specifically limited, It is preferable that it is 1-50 mass parts with respect to 100 mass parts of (A) cyclic olefin resin, and it is 5-30 mass parts. More preferred. (B) When content of a photo-acid generator is less than the said lower limit, the exposure of a photosensitive adhesive composition and a development characteristic may become bad. On the other hand, if the content of the (B) photoacid generator exceeds the upper limit, the sensitivity is significantly lowered, which is not preferable.

<(C) Aliphatic epoxy compound>
(C) An aliphatic epoxy compound has a function which can bridge | crosslink (A) cyclic olefin resin.

  (C) The aliphatic epoxy compound may have a cyclic structure, but is preferably a branched structure or a linear structure, and more preferably a branched structure. By including the (C) aliphatic epoxy compound having a branched structure, the crosslinking density of the (A) cyclic olefin resin in the photosensitive adhesive composition is increased. For this reason, the adhesive layer 601 has appropriate flexibility. When the adhesive layer 601 has appropriate flexibility, it can have stress relaxation properties that relieve stress concentration (for example, stress accompanying thermal expansion) generated at the bonding interface between the semiconductor chips 20. By providing the adhesive layer 601 containing a norbornene-based resin between the semiconductor chips 20, it is possible to prevent the semiconductor chip 20 from being troubled such as cracking or chipping.

  The (C) aliphatic epoxy compound is preferably a compound containing two or more glycidyl groups in the molecule, and is a compound containing three or more and nine or less glycidyl groups in the molecule. More preferred. Thereby, since the crosslinking density of (A) cyclic olefin resin in a photosensitive adhesive composition becomes high, the stress relaxation property of the contact bonding layer 601 can be made more excellent.

Examples of such (C) aliphatic epoxy compounds include, for example, epoxy-based compounds such as ethylene glycol diglycidyl ether, propylene glycol diglycidyl ether, polyethylene glycol diglycidyl ether, polypropylene glycol diglycidyl ether, and trimethylolpropane. Examples include triglycidyl ether, trimethylolethane triglycidyl ether, sorbitol polyglycidyl ether, pentaerythritol polyglycidyl ether, and the like, and one or more of these can be used in combination. Among these, trimethylolpropane triglycidyl ether is particularly preferable. Thereby, the crosslinking reaction of (A) cyclic olefin resin in a photosensitive adhesive composition can be accelerated | stimulated. Therefore, it is possible to obtain an adhesive layer 601 particularly excellent in adhesiveness and stress relaxation properties.

  (C) Although content of an aliphatic epoxy compound is not specifically limited, It is preferable that it is 1-100 mass parts with respect to 100 mass parts of (A) cyclic olefin resin, and it is 5-50 mass parts. More preferred. (C) If the content of the aliphatic epoxy compound is less than the lower limit, the physical properties after curing of the photosensitive adhesive composition may be poor. (C) When content of an aliphatic epoxy compound exceeds the said upper limit, the viscosity of a photosensitive adhesive composition may become high too much more than necessary.

<(D) Phenol compound having a hydroxyl group equivalent of 60 to 150 g / eq>
(D) A phenolic compound having a hydroxyl group equivalent of 60 to 150 g / eq (hereinafter sometimes simply referred to as “(D) phenolic compound”) has a function of improving the sensitivity of the photosensitive adhesive composition to light. . For this reason, the undissolved residue of the photosensitive adhesive composition after development can be prevented. Further, (B) the residual film ratio can be improved by interacting with the photoacid generator. For this reason, the patterning property during development can be improved.

  Here, the (D) phenol compound has a hydroxyl group equivalent of 60 to 150 g / eq, preferably a hydroxyl group equivalent of 70 to 140 g / eq, and more preferably a hydroxyl group equivalent of 75 to 135 g / eq. . When the hydroxyl equivalent is within the above range, it becomes soluble in an alkaline aqueous solution used during development. On the other hand, if the hydroxyl equivalent is less than the lower limit, there is a risk that the exposure will not be performed during the exposure process. On the other hand, if the hydroxyl equivalent exceeds the upper limit, the solubility in an alkaline aqueous solution is difficult to be exhibited, and undissolved residue is generated, and pattern processing cannot be performed sufficiently.

  The hydroxyl group equivalent in the resin can be measured by titration of the resin solution using a standard alkaline solution.

  (D) Preferred specific examples of the phenol compound include, for example, 4-ethylresorcinol, 2-propylresorcinol, 4-butylresorcinol, 4-hexylresorcinol, 2-hydroxybenzoic acid, 3-hydroxybenzoic acid, 4 -Hydroxybenzoic acid, 4,4'-dihydroxydiphenyl sulfide, 3,3'-dihydroxydiphenyl disulfide, 4,4'-dihydroxydiphenyl sulfone, 2,2'-dihydroxydiphenylmethane, 4,4'-dihydroxydiphenylmethane, 2, 2'-dihydroxydiphenyl ether, 4,4'-dihydroxydiphenyl ether, 4,4 '-(1,3-dimethylbutylidene) diphenol, 4,4'-(2-ethylhexylidene) diphenol, 4,4 '-Ethylidenebispheno 2,2,2'-ethylenedioxydiphenol, 3,3'-ethylenedioxydiphenol, 1,5-bis (o-hydroxyphenoxy) -3-oxapentane, diphenoic acid, Bis-Z (Honshu Chemical) Industrial-made), Ph-RS-Z (made by Honshu Chemical Industry), etc. are mentioned, Among these, it can use 1 type or in combination of 2 or more types.

(D) It is preferable that content of a phenol compound is 0.5-20 mass parts with respect to 100 mass parts of (A) cyclic olefin resin, and it is more preferable that it is 1-10 mass parts. (D) When content of a phenol compound is less than the said lower limit, the effect of a sensitivity improvement and the improvement of undissolved may not fully be recognized. (D) When the content of the phenol compound exceeds the above upper limit, pattern collapse occurs during development and precipitation occurs during frozen storage, which is not preferable.

  The photosensitive adhesive composition further includes phenol resins, leveling agents, antioxidants, flame retardants, plasticizers, silane coupling agents, curing accelerators, etc., if necessary, for the purpose of improving characteristics such as sensitivity. May be included.

<Method for Manufacturing Semiconductor Device>
Next, a method for manufacturing the semiconductor device of the present invention will be described.
2 to 4 are diagrams for explaining a method of manufacturing the semiconductor device of the present invention.

  The method for producing a semiconductor device of the present invention comprises a coating process for coating a liquid containing a photosensitive adhesive composition on a wafer, an exposure process for exposing the obtained coating film, and a coating film in an unexposed area by development. The developing process to be removed, the processing process for etching and ashing the opening formed in the unexposed area, the back grinding process for grinding the back surface of the wafer, and dicing the wafer into a plurality of semiconductor chips. And a mounting step of picking up a semiconductor chip and mounting it on the package substrate, and then picking up another semiconductor chip and press-bonding it onto the semiconductor chip previously mounted. Hereinafter, each process will be described sequentially.

[1] Application Step First, a wafer (semiconductor wafer) for cutting out the semiconductor chip 20 is prepared, and a liquid containing a photosensitive adhesive composition is applied thereon. Thereby, a coating film is obtained on a wafer.

  A coating method is not particularly limited, and examples thereof include a spin coating method, a spray coating method, an ink jet method, a roll coating method, and a printing method.

  If necessary, the applied liquid (liquid film) may be heated and dried (pre-baking). In this case, the heating temperature is preferably about 70 to 160 ° C, and more preferably about 80 to 150 ° C. Moreover, although heating time is suitably set according to heating temperature, it is preferable that it is about 5 second-30 minutes, and it is more preferable that it is about 10 second-15 minutes.

  FIG. 2A is a diagram illustrating an example in which a coating film 601 a is formed by applying a liquid containing a photosensitive adhesive composition to the surface of the wafer 201.

The liquid containing the photosensitive adhesive composition is prepared by appropriately adding a solvent or the like that dissolves the liquid to the photosensitive adhesive composition of the present invention. Moreover, it is preferable that the solvent to be used is a solvent that can be volatilized and removed when heated in a process described later. Specifically, toluene, xylene, benzene, dimethylformamide, tetrahydrofuran, ethyl cellosolve, ethyl acetate, N-methyl-2-pyrrolidone, γ-butyrolactone, N, N-dimethylacetamide, dimethyl sulfoxide, diethylene glycol dimethyl ether, diethylene glycol diethyl ether , Diethylene glycol dibutyl ether, propylene glycol monomethyl ether, dipropylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, methyl lactate, ethyl lactate, butyl lactate, methyl ethyl ketone, cyclohexanone, tetrahydrofuran, methyl-1,3-butylene glycol acetate, 1,3 -Butylene glycol-3-monomethyl ether, methyl pyruvate , Ethyl pyruvate, include methyl 3-methoxy propionate or the like, can be used singly or in combination of two or more of them. Of these, propylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, γ-butyrolactone, and cyclohexanone are preferred because of their high solubility and easy removal by volatilization.

[2] Exposure Step Next, the coating film 601a formed on the wafer 201 is subjected to exposure processing in a desired pattern shape. Thereby, a photocuring reaction occurs in the coating film 601a in the exposed region, and a cured film having a desired pattern shape is obtained.

  As light used for the exposure process, electromagnetic waves and particle beams having various wavelengths are used. For example, ultraviolet rays such as i-rays, visible rays, lasers, X-rays, electron beams, and the like are used. Among these, ultraviolet rays or visible rays having a wavelength of about 200 to 700 μm are preferably used. The exposure process can be performed in, for example, an air atmosphere, an inert gas atmosphere, or a reduced pressure atmosphere.

  In this exposure step, for example, by exposing through a photomask, a photocuring reaction is caused to occur in the coating film existing in a desired pattern region. Note that the use of a photomask can be omitted when a highly directional material such as an X-ray or an electron beam is used.

Although the exposure amount in the exposure processing is appropriately set according to the sensitivity of the photosensitive adhesive composition, it is preferably about 30 to 3000 mJ / cm ² as an example.

[3] Development Step Next, the coating film 601a subjected to the exposure processing is subjected to development processing. Thereby, the coating film 601a of an unexposed part is removed and a desired pattern shape is obtained. By such development processing, for example, a pad for connecting the bonding wire 70 to the semiconductor chip 20 can be exposed, or a coating film on the dicing line can be removed in a dicing process described later.

  In the development process, the developer is brought into contact with the coating film 601a subjected to the exposure process. Thereby, the coating film 601a of an unexposed part melt | dissolves in a developing solution, and is removed. Developers include, for example, alkali metal carbonates, alkali metal hydroxides, alkali developers such as tetraammonium hydroxide, organic developers such as dimethylformamide, N-methyl-2-pyrrolidone, and the like. In particular, an alkali developer is preferably used. Alkali developers have the characteristics that the burden on the environment is small and residues are not easily generated.

  Moreover, as a supply method of a developing solution, systems, such as a spray, a paddle, immersion, and an ultrasonic wave, are mentioned, for example.

[4] Processing Step Next, the wafer 201 exposed by the development step is subjected to an etching process as necessary. Thereby, when the passivation film is formed on the surface of the wafer 201, it can be removed and the pad for connecting the bonding wire 70 can be exposed.

Examples of the etching process include plasma etching (dry etching), various wet etching processes, and the like. Among these, the plasma etching treatment can be performed under generally known conditions. For example, fluorine compound gas (CF ₄ , CHF ₃ ), fluorine compound gas (CF ₄ , CHF ₃ ) and oxygen Using gas mixture with gas (O ₂ ), mixture gas of fluorine compound gas (CF ₄ , CHF ₃ ) and argon gas (Ar), output is 200 to 2000 W, time is 0.2 to 15 minutes, gas flow rate 50-1000
sccm.

  Thereafter, an ashing process is performed as necessary. Thereby, the process residue etc. which generate | occur | produced by the etching process can be removed, and the coating-film 601a surface and the pad surface can be cleaned. As a result, the adhesive force of the adhesive layer 601 can be increased, and the bonding force of the bonding wire 70 to the pad can be increased.

Examples of the ashing process include a wet process using a chemical such as a plasma process. Among these, the conditions for performing the plasma treatment are, for example, oxygen gas (O ₂ ), a mixture gas of oxygen gas (O ₂ ) and argon gas (Ar), etc., the output is 200 to 2000 W, and the time is 0.2. The gas flow can be performed under conditions of ˜15 minutes and gas flow of 50˜1000 sccm.

[5] Back Grinding Step Next, as shown in FIG. 2C, the back surface of the wafer 201 is ground (back grinding). Thereby, the dotted line portion in FIG. 2C is removed, and the thickness of the wafer 201 can be reduced. As a result of this grinding, the thickness of the wafer 201 is reduced to about 20 to 100 μm although it varies depending on the original thickness.
For this grinding, for example, a device called a back grinding wheel is used.

  FIG. 2B is a view showing a state where the back grind film 90 is attached to the surface of the wafer 201 on which the coating film 601a is formed (the upper surface of FIG. 2A). The back grinding process can be performed by attaching the back grinding film 90 to the surface of the wafer 201 and fixing the wafer 201 in this manner. 2B, the wafer 201 on which the coating film 601a is formed is turned upside down with respect to FIG. 2A.

[6] Dicing process Next, the wafer is subjected to a dicing process. As a result, the wafer is cut into a plurality of semiconductor chips 20 and separated into individual pieces.

  In the dicing process, the wafer 201 is attached to a dicing die attach film or a dicing film. This dicing die attach film or dicing film fixes the wafer 201 during the dicing process.

  2 (d1) and 2 (d2) are diagrams showing an example in which a back grind film 90 is attached to the back surface (the top surface of FIG. 2 (c)) of the wafer 201 whose back surface is ground. 2D1 illustrates a wafer 201 and the like for cutting out the semiconductor chip 20 in the lowermost layer (the layer closest to the package substrate 30) of the chip stack 200, while FIG. 2D2 These show a wafer 201 and the like for cutting out semiconductor chips 20 other than the lowermost layer of the chip stack 200. Further, in FIGS. 2 (d1) and 2 (d2), the wafer 201 on which the coating film 601a is formed is turned upside down with respect to FIG. 2 (c).

  In FIG. 2D1, a dicing die attach film 100 that is a laminate of a dicing film 100a and a die attach film 100b is attached to the back surface of the wafer 201, while in FIG. The dicing film 100a is affixed on the back surface.

Next, as shown in FIG. 3 (e1) and FIG. 3 (e2), the back grind film 9
Remove 0.

  Next, as shown in FIGS. 3 (f1) and 3 (f2), a dicing process is performed. In the dicing process, as shown in FIGS. 3 (f1) and 3 (f2), the dicing blade 110 reaches the dicing film 100a. As a result, as shown in FIG. 3 (f1), the coating film 601a, the wafer 201, and the die attach film 100b are separated into individual pieces, and an individual piece 21 formed by laminating the adhesive layer 601, the semiconductor chip 20, and the adhesive layer 101 is obtained. Cut out. Similarly, as shown in FIG. 3 (f2), the coating film 601a and the wafer 201 are separated into individual pieces, and the individual pieces 22 formed by laminating the adhesive layer 601 and the semiconductor chip 20 are cut out.

[7] Mounting Process FIGS. 4 (g1) and 4 (g2) are diagrams illustrating an example in which the cut piece 21 and the piece 22 are picked up by the collet 121 of the bonding apparatus 120, respectively.

  Next, the individual piece 21 is picked up by the collet 121 of the bonding apparatus 120 and is crimped (mounted) on the package substrate 30. At this time, the back surface of the semiconductor chip 20 and the package substrate 30 are bonded via an adhesive layer 101 as shown in FIG. In addition, this contact bonding layer 101 may be comprised with the photosensitive adhesive composition of this invention other than the piece of the die attach film 100b, for example.

  Then, the piece 22 is crimped | bonded on the piece 21 mounted previously. Thereby, as shown in FIG. 4B, two semiconductor chips 20 can be stacked via the adhesive layer 601. Thereafter, by repeating this step, as shown in FIG. 4C, a chip stack 200 in which a large number of semiconductor chips 20 are stacked is obtained. At this time, by stacking the semiconductor chips 20 while shifting the positions thereof, it is possible to secure a region to which the bonding wires 70 are connected.

  Further, when the semiconductor chip 20 is mounted, the adhesive layer 601 is heated. Thereby, sufficient adhesive force is expressed in the adhesive layer 601, and the semiconductor chips 20 can be firmly bonded to each other. In this case, the heating temperature is preferably about 30 to 150 ° C. Moreover, it is preferable that the crimping | compression-bonding load at the time of mounting is about 0.1-100N, and the crimping | compression-bonding time is about 0.1-10 seconds.

  Thereafter, the electrode portion of each semiconductor chip 20 and the exposed portion of the wiring 34 of the package substrate 30 are connected by a bonding wire 70 as shown in FIG.

  And the semiconductor device 10 shown in FIG. 1 is obtained by shape | molding a mold part so that the chip laminated body 200 may be covered.

  The molding of the mold part can be performed, for example, by using a transfer molding machine and injecting a sealing material into the mold. In that case, it is preferable that the temperature of the mold is about 130 to 250 ° C., the injection pressure is about 3 to 10 MPa, and the holding time after injection is about 10 seconds to 10 minutes.

  After mold release, the molded part and the adhesive layer 601 can be finally cured by heating the molded body as necessary. In this case, the heating temperature is preferably about 130 to 250 ° C., and the heating time is preferably about 10 minutes to 10 hours.

As mentioned above, although this invention was demonstrated, this invention is not limited to this, For example,
Arbitrary components may be added to the photosensitive adhesive composition. Further, an arbitrary structure may be added to the semiconductor device.

Next, specific examples of the present invention will be described.
(Example 1)
[1] Polymer Synthesis All glass equipment was dried at 60 ° C. and 0.1 torr for 18 hours. Thereafter, glass equipment was installed in the glow box.

  In a container, toluene (992 g), dimethoxyethane (116 g), 1,1-bistrifluoromethyl-2- (bicyclo [2.2.1] hept-2-en-5-yl) ethyl alcohol (hereinafter, HFANB) ( 148 g, 0.54 mol), ethyl 3- (bicyclo [2.2.1] hept-2-en-2-yl) propanate (hereinafter, EPEsNB) (20.7 g, 0.107 mol), 5-((2 -(2-Methoxyethoxy) ethoxy) methyl) bicyclo [2.2.1] hept-2-ene (hereinafter NBTON) (61.9 g, 0.274 mol) was charged. Purge was performed by flowing nitrogen for 30 minutes while heating the reaction solvent at 45 ° C. To perform sequential addition, additional EPEsNB (14.2 g, 0.073 mol) and NBTON (46.7 g, 0.159 mol) were mixed in a separate container and purged with nitrogen. After complete purging, bis (toluene) bis (perfluorophenyl) nickel (5.82 g, 0.012 mol) dissolved in 60.5 ml of toluene was charged into the reaction vessel. At the same time, the combined monomers were added at a rate to keep unreacted monomers at a constant level for polymerization (3 hours).

  After removing the unreacted monomer by dissolving the reaction solution in about 1 L of methanol / THF (= 4 mol / 5 mol) solution, sodium hydroxide / sodium acetate (= 4.8 mol) at 60 ° C. for 4 hours. The ester was hydrolyzed by using 1 mol) of sodium hydroxide solution. Thereafter, methanol (405 g), THF (87 g), acetic acid (67 g), formic acid (67 g) and deionized water (21 g) were added, and the mixture was stirred at 50 ° C. for 15 minutes. When stirring is stopped, the solution separates into an aqueous layer and an organic layer. Therefore, the upper aqueous layer is removed, and the organic layer is washed with a methanol / deionized water (= 390 g / 2376 g) solution three times at 60 ° C. for 15 minutes. did. Finally, the polymer was diluted in a solvent and replaced with a solvent.

  The yield of the polymer in the synthesis was 93.1%, the weight average molecular weight (Mw) of the obtained polymer was 85,900, and the molecular weight dispersion (PD) of the obtained polymer was 2.52.

The polymer composition of the obtained (A-1) was from ¹ H-NMR to 45.0 mol% of HFANB, 2- (bicyclo [2.2.1] hept-2-en-5-yl) propionic acid (hereinafter referred to as “HFANB”). , EPENB) was 15.0 mol% and NBTON was 40.0 mol%.

(In formula (7), l: m: n = 45: 15: 40)

(Cyclic olefin resin A-1)
The compound represented by the above formula (7) was used as the cyclic olefin-based resin A-1.

[2] Production of photosensitive resin composition Other raw materials used in the photosensitive resin composition of Example 1 are shown below.

(Photoacid generator B-1)
A compound represented by the following formula (8) was prepared as the photoacid generator B-1.

(Aliphatic epoxy compound C-1)
A compound represented by the following formula (9) was prepared with C-1 as the aliphatic epoxy compound.

(Phenol compound D-1)
As the phenol compound D-1, a compound represented by the following formula (10) was prepared. The hydroxyl equivalent of such a compound is 100 g / eq.

(Antioxidant E-1)
As the antioxidant E-1, a compound represented by the following formula (11) was prepared.

(Antioxidant E-2)
As the antioxidant E-2, a compound represented by the following formula (12) was prepared.

  Cyclic olefin resin A-1 (22.0 parts by weight), photoacid generator B-1 (5.0 parts by weight), aliphatic epoxy compound C-1 (5.0 parts by weight), phenol compound D-1 (3.0 parts by weight), antioxidant E-1 (3.0 parts by weight), antioxidant E-2 (2.0 parts by weight), propylene glycol methyl ether acetate as solvent (60.0 parts by weight) Part) to obtain a uniform photosensitive resin composition of Example 1.

(Examples 2-8, Comparative Examples 1-4)
A photosensitive resin composition was obtained in the same manner as in Example 1 except that the raw materials constituting the photosensitive resin composition were changed to those shown in Table 1 and the respective contents were changed to the contents shown in Table 1.

  In addition, the other raw material used with the photosensitive resin composition of each Example and a comparative example is shown below.

(Cyclic olefin resin A-2)
A compound represented by the following formula (13) was prepared as the cyclic olefin-based resin A-2.

(In formula (13), l: m: n = 25: 15: 60)

(Cyclic olefin resin A-3)
A compound represented by the following formula (14) was prepared as the cyclic olefin-based resin A-3.

(In formula (14), l: m: n = 25: 35: 40)

(Phenol compound D-2)
A compound represented by the following formula (15) was prepared using D-2 as the phenol compound. The hydroxyl equivalent of such a compound is 135 g / eq.

(Phenol compound D-3)
A compound represented by the following formula (16) was prepared with the phenol compound as D-3. The hydroxyl equivalent of such a compound is 83 g / eq.

(Phenol compound D-4)
A compound represented by the following formula (17) was prepared using D-4 as the phenol compound. The hydroxyl equivalent of such a compound is 165 g / eq.

(Phenol compound D-5)
A compound represented by the following formula (18) was prepared with a phenol compound as D-5. The hydroxyl equivalent of such a compound is 55 g / eq.

  The following evaluation was performed about the photosensitive resin composition of each Example and each comparative example which were obtained as mentioned above.

[3] Evaluation of Photosensitive Adhesive Composition [3.1] Evaluation of Elastic Modulus [3.1.1] Evaluation of Elastic Modulus Before Curing The photosensitive adhesive composition of each example and each comparative example It was applied onto a silicon wafer, pre-baked at 120 ° C. for 5 minutes, and then heat-treated at 150 ° C. for 40 minutes. After that, using an ultra-micro hardness meter ENT-1000 (manufactured by Elionix), the measurement temperature is 25 ° C., the load is 2 mN, the holding time is 1 second, and a Berkovich indenter (triangular pyramid, 115 ° opposite ridge angle) is used. The elastic modulus of the coating film on the silicon wafer was measured according to the standard. This was made into the elasticity modulus (unit: GPa) in 25 degreeC of the state before hardening of a photosensitive adhesive composition.
In addition, about the photosensitive adhesive composition of the comparative example 4, the elasticity modulus was not able to be measured.

[3.1.2] Evaluation of Elastic Modulus after Curing The photosensitive adhesive compositions of each Example and each Comparative Example were applied on a silicon wafer, pre-baked at 120 ° C. for 5 minutes, 150 ° C., 40 Heat treatment was performed for a minute. And in addition, 1
It was cured by heating in an oven at 75 ° C. for 120 minutes.
After that, using an ultra-micro hardness meter ENT-1000 (manufactured by Elionix), the measurement temperature is 25 ° C., the load is 2 mN, the holding time is 1 second, and a Berkovich indenter (triangular pyramid, 115 ° opposite ridge angle) is used. The elastic modulus of the coating film on the silicon wafer was measured according to the standard. This was made into the elastic modulus (unit: GPa) in 25 degreeC of the hardened | cured material of the photosensitive adhesive composition.
In addition, about the photosensitive adhesive composition of the comparative example 4, the elasticity modulus was not able to be measured.

[3.2] Evaluation of Adhesive Strength to Semiconductor Element Silicon semiconductor chips were bonded to each other through the photosensitive adhesive compositions of the examples and comparative examples to prepare samples for evaluation. Next, with respect to the obtained evaluation sample, the die shear strength (unit: N) per chip when the joint surface between the chips is broken by pressing the horizontal direction from the side with a shear tool using a Dage 4000 (manufactured by Dage). Was measured. The chip size was 4 mm × 4 mm.
In addition, about the photosensitive adhesive composition of the comparative example 4, die shear strength was not able to be measured.

[3.3] Evaluation of Adhesive Strength of Etching and Ashing Coating Film (Before Curing) to Backgrind Film First, photosensitive adhesive compositions of Examples and Comparative Examples on a silicon semiconductor chip Was applied and prebaked at 120 ° C. for 5 minutes. This obtained the coating film.

Next, the obtained coating film was sequentially subjected to etching treatment and dicing treatment. The etching process uses a mixed gas of fluorine compound gas (CF ₄ ), argon gas (Ar) and oxygen gas (O ₂ ), the output is 2500 W, the time is 6 minutes, and the CF ₄ flow rate / Ar flow rate / O ₂ flow rate is The ashing was performed using a mixed gas of O ₂ and Ar, the output was 600 W, the time was 12 minutes, and the O ₂ flow rate / Ar flow rate was 50 sccm / 150 sccm.

  Next, a UV peeling type back grind film was bonded so that the adhesive surface was in contact with the coating film. The back grind film used has a width of 25 mm and a length of 75 mm.

Then, the back grind film is peeled off from the coating film so that the peel angle is 180 ° from one end in the longitudinal direction of the back grind film, and the average value of the load required for peeling (180 ° peel adhesive strength, unit: N / 25 mm, conforming to JIS Z 0237). The measurement temperature was 25 ° C., and the peeling speed was 10.0 ± 0.2 mm / s.
In addition, about the photosensitive adhesive composition of the comparative example 4, adhesive force was not able to be measured.

[3.4] Evaluation of adhesive strength of back-grind film after UV irradiation treatment of coating film (before curing) after etching treatment and ashing treatment First, the photosensitivity of each example and each comparative example on a silicon semiconductor chip The adhesive adhesive composition was applied and prebaked at 120 ° C. for 5 minutes. This obtained the coating film.

Next, an etching process and an ashing process were sequentially performed on the obtained coating film. The etching process uses a mixed gas of fluorine compound gas (CF ₄ ), argon gas (Ar) and oxygen gas (O ₂ ), the output is 2500 W, the time is 6 minutes, and the CF ₄ flow rate / Ar flow rate / O ₂ flow rate is The ashing process is performed using a mixed gas of O ₂ and Ar, the output is 600 W, the time is 12 minutes, and the O ₂ flow rate / Ar flow rate is 50 sccm / 15.
Performed at 0 sccm.

  Next, a UV peeling type back grind film was bonded so that the adhesive surface was in contact with the coating film. The back grind film used has a width of 25 mm and a length of 75 mm.

Then, after applying UV irradiation treatment (wavelength 365 nm) of 600 mJ / cm ² to the back grind film and the paint film, the back grind is applied from the paint film so that the peel angle is 180 ° from one end in the longitudinal direction of the back grind film. The film was peeled off, and the average value of the load required for peeling off (180 ° peeling adhesive strength, unit: N / 25 mm, JIS Z 0237 compliant) was determined. The measurement temperature was 25 ° C., and the peeling speed was 10.0 ± 0.2 mm / s.
In addition, about the photosensitive adhesive composition of the comparative example 4, adhesive force was not able to be measured.

[3.5] Evaluation of minimum melt viscosity The photosensitive adhesive composition of each Example and each Comparative Example was applied on a base material sheet coated with a release agent, pre-baked at 120 ° C for 3 minutes, and then 100 ° C. , Heat treatment for 60 minutes was performed. Then, the obtained coating film was peeled off from the base material sheet to obtain a test piece having a length of 20 mm, a width of 20 mm, and a film thickness of 100 μm. About this test piece, melt viscosity was measured at a frequency of 1 Hz, using a rheometer (Rheo Stress RS150 manufactured by HAAKE) while raising the temperature from 30 ° C. to 200 ° C. at a rate of 10 ° C./min.
And the minimum value of the measured value was calculated | required as minimum melt viscosity.
For the photosensitive adhesive composition of Comparative Example 4, the minimum melt viscosity could not be measured.

[3.6] Evaluation of presence / absence of cracks after temperature cycle (TCT) test The silicon semiconductor chips are bonded to each other through the photosensitive adhesive composition of each example and each comparative example, and the chip stack is formed. Produced. This was mounted on a package substrate using a die bonding sheet, sealed with a sealing material after wire bonding. Thereby, a semiconductor device was obtained. The sealing conditions were a mold temperature of 175 ° C., an injection pressure of 7 MPa, a holding time of 2 minutes, a heating temperature after release of 175 ° C., and a heating time of 2 hours.

  Next, 100 obtained semiconductor devices were subjected to a temperature cycle test (high temperature and low temperature 30 minutes each) at a temperature of −55 ° C. to 125 ° C. for 500 cycles, and the semiconductor device after the test was observed with an ultrasonic flaw detector. And the observation result was evaluated based on the following evaluation criteria. In addition, in the photosensitive adhesive composition of the comparative example 4, a chip laminated body was not able to be produced.

<Evaluation criteria>
(Double-circle): A crack or interface peeling is not recognized at all.
○: The rate of occurrence of cracks or interface peeling is less than 3%.
(Triangle | delta): The incidence rate of a crack or interface peeling is 3% or more and less than 5%.
X: The rate of occurrence of cracks or interfacial peeling is 5% or more.
The above evaluation results are shown in Table 1.

  As is clear from Table 1, the semiconductor device manufactured using the photosensitive adhesive composition of each example sufficiently suppressed the occurrence of cracks and interfacial delamination even in a harsh environment. . This means that even if the temperature changes suddenly, the adhesive layer adheres and fixes the semiconductor chips well without causing the adhesion between the semiconductor chips to be released or causing problems in the semiconductor chips. It shows that. That is, it has been clarified that the photosensitive adhesive composition of the present invention can satisfactorily bond semiconductor chips while relaxing stress concentration in bonding between semiconductor chips.

  On the other hand, in the semiconductor device manufactured using the photosensitive adhesive composition of each comparative example, a relatively large number of cracks or interface peeling was observed after the temperature cycle test. This can be considered that due to a rapid change in temperature, the bonding between the semiconductor chips by the adhesive layer has been released, or cracks due to stress concentration have occurred on the semiconductor chip.

DESCRIPTION OF SYMBOLS 10 Semiconductor device 101 Adhesion layer 20 Semiconductor chip 200 Chip laminated body 201 Wafer 21, 22 Piece 30 Package substrate 31 Core substrate 32 Insulating layer 33 Solder resist layer 34 Wiring 35 Conductive via 50 Mold part 601 Adhesive layer 601a Coating film 70 Bonding wire 80 Solder balls 90 Back grind film 100 Dicing die attach film 100a Dicing film 100b Die attach film 110 Dicing blade 120 Bonding device 121 Collet

Claims (4)

A photosensitive adhesive composition used between layers of a laminated semiconductor element,
The elastic modulus at 25 ° C. of the cured product is 2.0 to 3.5 GPa,
The elastic modulus at 25 ° C. before curing is 70 to 120% of the elastic modulus at 25 ° C. of the cured product,
The adhesive strength at 25 ° C. to the semiconductor element of the composition before curing subjected to etching treatment and ashing treatment is 20 to 200 N,
The photosensitive adhesive composition characterized by the minimum melt viscosity in 100-200 degreeC of the composition before hardening being 20-500 Pa.s.   The composition before curing subjected to the etching treatment and the ashing treatment has an adhesive strength at 25 ° C. of 3.0 N / 25 mm or more to the UV peeling type back grind film, and the composition before curing subjected to the UV irradiation treatment. The photosensitive adhesive composition according to claim 1, wherein the adhesive strength at 50 ° C. of the back grind film is 0.5 N / 25 mm or less.   The photosensitive adhesive composition of Claim 1 or 2 containing cyclic olefin resin.   A semiconductor device comprising a stacked semiconductor element formed by stacking semiconductor elements through a cured product of the photosensitive adhesive composition according to claim 1.