Manufacturing method for semiconductor devices

Abstract

The object of the present invention is to provide a method for manufacturing a semiconductor device having a redistribution layer made of an interlayer insulating film that forms high-density wiring and has low dielectric loss tangent and low thermal expansion coefficient characteristics. [Solution] The above problem can be solved by a method for manufacturing a semiconductor device using a redistribution layer obtained by the steps of: forming an interlayer insulating film with a thickness in the range of 0.5 μm to 12 μm; forming a film of a polysiloxane photosensitive resin composition on the interlayer insulating film, and forming a patterned protective layer by exposing and developing the film; removing the interlayer insulating film exposed below the opening of the protective layer by dry etching to form at least one pattern having a line width in the range of 0.5 to 6.0 μm on the interlayer insulating film; and peeling off the patterned protective layer.

Description

[Technical Field]

[0001] This invention relates to a method for manufacturing a semiconductor device. [Background technology]

[0002] Traditionally, the integration of semiconductor devices has progressed through miniaturization in the front-end process. However, in recent years, this approach has reached its limits, and development is actively focused on achieving high integration through back-end packaging technology. A typical example is fan-out packaging technology, which combines a semiconductor chip covered with molded resin with a redistribution layer consisting of an interlayer insulating film and metal wiring, thereby forming fine wiring even in areas outside the chip. Furthermore, technologies are being developed to package multiple semiconductor chips together using an organic substrate containing this redistribution layer as an intermediate substrate.

[0003] The redistribution layer used in such packaging technology is mainly manufactured by repeatedly applying and patterning photosensitive polyimide resins to form an interlayer insulating film and then forming metal wiring such as copper, enabling the creation of thin and high-density packages. (Patent Document 1) [Prior art documents] [Patent Documents]

[0004] [Patent Document 1] Patent No. 6848434 [Overview of the project] [Problems that the invention aims to solve]

[0005] However, with the further evolution of semiconductor devices, conventional interlayer insulating films made of photosensitive polyimide resins and the like lacked the resolution necessary to handle increasingly high-density wiring, and also presented many challenges, such as transmission loss due to high dielectric loss tangent, and warping and cracking due to high thermal expansion coefficients. To solve these problems, one method is to fabricate a non-photosensitive insulating film, such as a polyimide resin, and then process it with a pattern, but there are limited methods capable of forming fine patterns of several micrometers. One such method involves coating a photosensitive resin as an etching protective layer on a non-photosensitive insulating film, patterning it, and then processing the insulating film by etching. However, because non-photosensitive insulating films with the above characteristics have high etching resistance, the film thickness of the photosensitive resin must be increased accordingly, resulting in a problem of reduced resolution.

[0006] Therefore, the present invention aims to provide a method for manufacturing a semiconductor device having a redistribution layer made of an interlayer insulating film that has low dielectric loss tangent and low thermal expansion coefficient, and which allows for the formation of high-density patterns by using a polysiloxane photosensitive resin composition with excellent dry etching resistance and high-resolution patterning as the etching protective layer. [Means for solving the problem]

[0007] After diligent research by the researchers, they found that the above problem can be solved with the following configuration.

[0008] 1) A method for manufacturing a semiconductor device having a semiconductor element and a redistribution layer consisting of wiring and an interlayer insulating film that are electrically connected to the semiconductor element, The aforementioned redistribution layer A process for forming an interlayer insulating film with a film thickness in the range of 0.5 μm to 12 μm. A step of forming a film of a polysiloxane photosensitive resin composition on the interlayer insulating film, and forming a patterned protective layer by exposing and developing the film. Removing the interlayer insulating film exposed under the opening of the protective layer by dry etching to form a pattern having a line width in the range of at least one of 0.5 to 6.0 μm in the interlayer insulating film; A method for manufacturing a semiconductor device, characterized in that it is obtained by a process including a peeling step of peeling the patterned protective layer.

[0009] 2). The method for manufacturing a semiconductor device according to 1), wherein the dielectric tangent of the interlayer insulating film at 10 GHz is 0.0100 or less.

[0010] 3). The method for manufacturing a semiconductor device according to 1) or 2), wherein the thermal expansion coefficient of the interlayer insulating film is 50 ppm / K or less.

[0011] 4). The method for manufacturing a semiconductor device according to any one of 1) to 3), wherein the interlayer insulating film contains a polyimide-based resin, a polybenzoxazole-based resin, a polyphenylene ether-based resin, a liquid crystal resin, a polystyrene-based resin, or a polyolefin-based resin.

[0012] 5). The method for manufacturing a semiconductor device according to any one of 1) to 4), wherein the aspect ratio (= film thickness of the interlayer insulating film ÷ via diameter) between the film thickness of the interlayer insulating film and the minimum pattern line width is in the range of 1.0 to 10.0.

[0013] 6). The method for manufacturing a semiconductor device according to any one of 1) to 5), wherein at least one of oxygen gas, noble gas, and hydrocarbon gas is used as the etching gas for dry etching of the interlayer insulating film.

[0014] 7). The method for manufacturing a semiconductor device according to any one of 1) to 6), wherein in the dry etching, the etching rate of the protective layer is 1 / 2 or less of the etching rate of the interlayer insulating film.

[0015] 8). The method for manufacturing a semiconductor device according to any one of 1) to 7), wherein the content of silicon atoms in the protective layer is 10% by weight or more.

[0016] 9) A method for manufacturing a semiconductor device according to any one of claims 1) to 8), characterized in that the polysiloxane photosensitive resin composition contains a compound having a structure represented by formula III or formula IV. (R in formula III) 4 , R 5 and R 6 Each of these independently represents an organic group with 1 to 20 carbon atoms. m represents an integer from 2 to 10, and n represents an integer from 0 to 10. Also, in formula IV, R 10 ~R 17 Each of these groups is independently selected from a range of monovalent groups, including hydrogen atoms, linear alkyl groups (methyl, ethyl, propyl, and butyl groups, etc.), cycloalkyl groups (cyclohexyl groups, etc.), aryl groups (phenyl and tolyl groups, etc.), groups in which some or all of the hydrogen atoms bonded to the carbon atoms of these groups are substituted with halogen atoms or cyano groups (chloromethyl, trifluoropropyl, and cyanoethyl groups, etc.), alkenyl groups (vinyl, allyl, butenyl, and hexenyl groups, etc.), (meth)acryloyl groups, epoxy groups, and organic groups containing mercapto or amino groups.

[0017] [ka]

[0018] [ka]

[0019] 10) A method for manufacturing a semiconductor device according to any one of items 1) to 9), characterized in that the polysiloxane photosensitive resin contains a compound having the structure represented by X1 or X2 below.

[0020] [ka]

[0021] 11) The interlayer insulating film is pyromellitic dianhydride, 3,3',4,4'-biphenyltetracarboxylic acid dianhydride, 4,4'-oxydiphthalic acid dianhydride, 3,3',4,4'-benzophenonetetracarboxylic acid dianhydride, 9,9-bis[4-(3,4-dicarboxyphenoxy)phenyl]fluorenidioanhydride, p-phenylenebis(trimellitate anhydride), 4,4'-bis(1,3-dioxo-1,3-dihydroisobenzofuran-5-ylcarbonyloxy)biphenyl, 4-[4-(1,3-dioxoisobenzofuran-5-ylcarbonyloxy)-2,3,5-trimethylphenyl]-2,3,6-trimethylphenyl1,3-dioxoisobenzofuran A method for manufacturing a semiconductor device according to any one of claims 1) to 10), characterized in that the polyimide resin contains one or more tetracarboxylic acid dianhydrides selected from n-5-carboxylate, 4-{[4-(1,3-dioxoisobenzofuran-5-ylcarbonyloxy)phenyl]cyclohexyl}phenyl 1,3-dioxoisobenzofuran-5-carboxylate, 4,4'-(4,4'-isopropylidene diphenoxy)diphthalic anhydride, 2,2-bis(4-hydroxyphenyl)propanedibenzoate-3,3',4,4'-tetracarboxylic acid dianhydride, and 4,4-(4,4'-isopropylidene diphenoxy)diphthalic anhydride.

[0022] 12) A method for manufacturing a semiconductor device according to any one of claims 1) to 11), characterized in that the interlayer insulating film is made of a polyimide resin containing one or more diamine components selected from p-phenylenediamine, 4,4'-diamino-2,2'-bis(trifluoromethyl)biphenyl, 4,4'-diamino-2,2'-dimethylbiphenyl, diaminodiphenylsulfone, 1,4-bis(4-aminophenoxy)benzene, 1,3-bis(4-aminophenoxy)benzene, 1,3-bis(3-aminophenoxy)benzene, 2-bis[4-(4-aminophenoxy)phenyl]hexafluoropropane, 1,4-bis(3-aminopropyldimethylsilyl)benzene, and 9,9-bis(4-aminophenyl)fluorene. [Effects of the Invention]

[0023] According to the present invention, it is possible to provide a method for manufacturing a semiconductor device having a redistribution layer made of an interlayer insulating film that forms high-density wiring and has low dielectric loss tangent and low thermal expansion coefficient characteristics. [Brief explanation of the drawing]

[0024] [Figure 1] This is a schematic cross-sectional view of the Funout package. [Figure 2] This is a schematic cross-sectional view of a package containing multiple chips, with an organic substrate including a redistribution layer as the intermediate substrate. [Modes for carrying out the invention]

[0025] The present invention relates to a method for manufacturing a semiconductor device having a semiconductor element and a redistribution layer consisting of wiring electrically connected to the semiconductor element and an interlayer insulating film, The aforementioned redistribution layer A process for forming an interlayer insulating film with a film thickness in the range of 0.5 μm to 12 μm. A step of forming a film of a polysiloxane photosensitive resin composition on the interlayer insulating film, and forming a patterned protective layer by exposing and developing the film. A step of removing the interlayer insulating film exposed below the opening of the protective layer by dry etching to form at least one pattern having a line width in the range of 0.5 to 6.0 μm in the interlayer insulating film. The present invention relates to a method for manufacturing a semiconductor device, characterized by being obtained by a process including a peeling step of peeling off a patterned protective layer.

[0026] The embodiments of the semiconductor device of the present invention will be described below with reference to the drawings. However, the present invention is not limited to the embodiments described below, and the processes, structures, etc., can be modified or added within the scope of its essence.

[0027] Figure 1 is a schematic cross-sectional view of a semiconductor device using a fan-out package according to one embodiment of the semiconductor device of the present invention. As shown in Figure 1, the semiconductor device 1 using a fan-out package is formed from a mold resin 3 covering a semiconductor chip 2 which is a semiconductor element, a redistribution layer 4, and an external connection terminal 5. The redistribution layer 4 is composed of an interlayer insulating film 4a and wiring 4b.

[0028] Figure 2 is a schematic cross-sectional view of a semiconductor device according to one embodiment of the present invention, in which an organic substrate including a redistribution layer 4 is used as an intermediate substrate, and multiple semiconductor chips are packaged together.

[0029] As an embodiment of the present invention, a method for manufacturing a semiconductor device using a fan-out package will be described as a representative example. First, semiconductor chips 2, which have completed the preceding processes and dicing, are placed on a support 6 at predetermined intervals. Next, a molding resin is applied to the support 6 and the semiconductor chips, cured, and molded. Then, the support 6 is peeled off, and the structure in which the semiconductor chips 2 and the molding resin are integrated is inverted. Next, an interlayer insulating film 4a is applied to the structure so that the film thickness is in the range of 0.5 μm to 12 μm, and the film is formed by firing. Furthermore, a polysiloxane photosensitive resin is applied to this interlayer insulating film 4a and dried to form a coating. The coating is then exposed and developed to pattern it and form a protective layer 7. Furthermore, the interlayer insulating film at the openings of the protective layer 7 is removed by dry etching to form the patterned interlayer insulating film 4a. The pattern of the interlayer insulating film 4a includes at least one pattern having a line width in the range of 0.5 to 6.0 μm. Next, the protective layer 7 is peeled off, and wiring 4b is formed at the openings of the interlayer insulating film.

[0030] The redistribution layer 4 may also be composed of a multilayer interlayer insulating film 4a and wiring 4b. In that case, the process of forming the interlayer insulating film 4a and wiring 4b will be repeated multiple times. Then, multiple external connection terminals 5 corresponding to each semiconductor chip 2 are formed, and the semiconductor chips are diced to create individual pieces, thereby obtaining the fan-out package 1.

[0031] In addition to the methods described above, the present invention can also be manufactured by first forming a redistribution layer on a specific substrate and then bonding it to the semiconductor chip and molding resin. In this case, the substrate used for forming the redistribution layer may be peeled off after bonding, or it may be incorporated into the semiconductor device as is.

[0032] [Interlayer insulating film] The interlayer insulating film of the present invention will be described in detail below.

[0033] The interlayer insulating film of the present invention does not have a patterning function on its own; patterning is formed by dry etching using a polysiloxane photosensitive resin as a protective layer, as described later. Subsequent wiring formation is carried out based on the pattern formed on the interlayer insulating film, so the line width of the pattern on the interlayer insulating film roughly corresponds to the line width of the wiring.

[0034] The thickness of the interlayer insulating film of the present invention is preferably in the range of 0.5 μm to 12 μm, more preferably in the range of 1.0 μm to 10 μm, and even more preferably in the range of 2.0 μm to 8 μm, from the viewpoint of maintaining insulation between wirings and making the overall thickness of the semiconductor device as thin as possible.

[0035] In order to form high-density wiring in the interlayer insulating film of the present invention, it is preferable to form a pattern with a line width in the range of 0.5 to 6.0 μm, and more preferably a pattern with a line width in the range of 0.5 to 3.0 μm.

[0036] The method for forming the interlayer insulating film of the present invention may involve applying an interlayer insulating film forming solution in which the material for forming the interlayer insulating film is dissolved, or by attaching an already formed film using lamination or the like.

[0037] As the interlayer insulating film of the present invention, in order to reduce the transmission loss of the semiconductor device, it is preferable that the dielectric loss tangent at 10 GHz is 0.0100 or less, more preferably 0.0060 or less, and even more preferably 0.0040 or less.

[0038] As the interlayer insulating film of the present invention, in order to suppress errors such as warping and cracking during the manufacture or use of semiconductor devices, it is preferable that the coefficient of thermal expansion is 50 ppm or less, more preferably 45 ppm or less, and even more preferably 30 ppm or less.

[0039] In the present invention, for high-density wiring formation, the aspect ratio between the thickness of the interlayer insulating film and the minimum pattern line width formed by dry etching (= thickness of the interlayer insulating film ÷ via diameter) is preferably in the range of 1.0 to 10.0, and preferably in the range of 2.0 to 10.0.

[0040] The materials constituting the interlayer insulating film of the present invention preferably contain polyimide resins, polybenzoxazole resins, polyphenylene ether resins, liquid crystalline resins, polystyrene resins, or polyolefin resins in order to exhibit the above-mentioned properties. Polyimide resins are preferred, especially from the viewpoint of heat resistance.

[0041] <Polyimide resin> The polyimide resin is not particularly limited as long as it is obtained by imidizing the precursor polyamic acid, and the tetracarboxylic dianhydride component and diamine component that are normally used in the synthesis of polyamic acid can be used.

[0042] <Tetracarboxylic acid dianhydride component> The tetracarboxylic dianhydride components include pyromellitic dianhydride, 3,3',4,4'-biphenyltetracarboxylic dianhydride, 2,3,3',4'-biphenyltetracarboxylic dianhydride, 2,3,2',3'-biphenyltetracarboxylic dianhydride, 4,4'-oxydiphthalic dianhydride, 3,4'-oxyphthalic dianhydride, 3,3',4,4'-benzophenonetetracarboxylic dianhydride, 2,2',3,3'-benzophenonetetracarboxylic dianhydride, norbornane-2-spiro-2'-cyclopentanone-5'-spiro-2''-no Lubornan-5,5'',6,6''-tetracarboxylic acid dianhydride, 2,2',3,3'-biphenyltetracarboxylic acid dianhydride, 4,4'-(hexafluoroisopropylidene)diphthalic acid anhydride, 5-(2,5-dioxotetrahydro-3-furanyl)-3-methyl-cyclohexene-1,2-dicarboxylic acid anhydride, 1,2,3,4-benzenetetracarboxylic acid dianhydride, 3,3',4,4'-diphenylsulfonetetracarboxylic acid dianhydride, methylene-4,4'-diphthalic acid dianhydride, 1,1-ethylidene-4,4'-diphthalic acid dianhydride, 2, 2-Propyridene-4,4'-diphthalic acid dianhydride, 1,2-ethylene-4,4'-diphthalic acid dianhydride, 1,3-trimethylene-4,4'-diphthalic acid dianhydride, 1,4-tetramethylene-4,4'-diphthalic acid dianhydride, 1,5-pentamethylene-4,4'-diphthalic acid dianhydride, thio-4,4'-diphthalic acid dianhydride, sulfonyl-4,4'-diphthalic acid dianhydride, 1,3-bis(3,4-dicarboxyphenyl)benzene dianhydride, 1,3-bis(3,4-dicarboxyphenoxy)benzene dianhydride, 1,4-bis(3,4-dicarboxyphenyl Phenoxy)benzene dianhydride, 1,3-bis[2-(3,4-dicarboxyphenyl)-2-propyl]benzene dianhydride, 1,4-bis[2-(3,4-dicarboxyphenyl)-2-propyl]benzene dianhydride, bis[3-(3,4-dicarboxyphenoxy)phenyl]methane dianhydride, bis[4-(3,4-dicarboxyphenoxy)phenyl]methane dianhydride, 2,2-bis[3-(3,4-dicarboxyphenoxy)phenyl]propane dianhydride, bis(3,4-dicarboxyphenoxy)dimethylsilane dianhydride, 1,3-bis(3,4-Dicarboxyphenyl)-1,1,3,3-tetramethyldisiloxane dianhydride, 3,4,9,10-perylenetetracarboxylic acid dianhydride, 2,3,6,7-naphthalenetetracarboxylic acid dianhydride, 2,3,6,7-anthracenetetracarboxylic acid dianhydride, 1,2,7,8-phenanthrenetetracarboxylic acid dianhydride, 9,9-bis[4-(3,4-dicarboxyphenoxy)phenyl]fluorenidioanhydride, p-phenylenebis(trimellitate anhydride), 4,4'-bis(1,3-dioxo-1,3-dihydroisobenzofuran-5-ylcarbonyloxy)biphenyl, 4-[4-(1,3-dioxoisobenzofuran-5-ylcarbonyl Examples include tetracarboxylic acid dianhydride, 4-{[4-(1,3-dioxoisobenzofuran-5-ylcarbonyloxy)phenyl]cyclohexyl}phenyl 1,3-dioxoisobenzofuran-5-carboxylate, 4,4'-(4,4'-isopropylidene diphenoxy)diphthalic anhydride, 2,2-bis(4-hydroxyphenyl)propanedibenzoate-3,3',4,4'-tetracarboxylic acid dianhydride, and 4,4-(4,4'-isopropylidene diphenoxy)diphthalic anhydride, which can be used individually or in combination. Depending on the required properties of the application field, an appropriate tetracarboxylic acid dianhydride component can be selected and used.

[0043] When obtaining a polyimide resin with low dielectric properties, from the above tetracarboxylic dianhydride components, pyromellitic dianhydride, 3,3',4,4'-biphenyltetracarboxylic dianhydride, 4,4'-oxydiphthalic dianhydride, 3,3',4,4'-benzophenonetetracarboxylic dianhydride, 9,9-bis[4-(3,4-dicarboxyphenoxy)phenyl]fluorendioanhydride, p-phenylenebis(trimellitate anhydride), 4,4'-bis(1,3-dioxo-1,3-dihydroisobenzofuran-5-ylcarbonyloxy)biphenyl, 4-[4-(1,3-dioxoisobenzofuran-5-ylcarbonyloxy)-2,3,5- It is preferable to use one or more acid dianhydrides selected from trimethylphenyl]-2,3,6-trimethylphenyl 1,3-dioxoisobenzofuran-5-carboxylate, 4-{[4-(1,3-dioxoisobenzofuran-5-ylcarbonyloxy)phenyl]cyclohexyl}phenyl 1,3-dioxoisobenzofuran-5-carboxylate, 4,4'-(4,4'-isopropylidene diphenoxy)diphthalic anhydride, 2,2-bis(4-hydroxyphenyl)propanedibenzoate-3,3',4,4'-tetracarboxylic dianhydride, and 4,4-(4,4'-isopropylidene diphenoxy)diphthalic anhydride.

[0044] <Diamine component> The diamine components include p-phenylenediamine, m-phenylenediamine, o-phenylenediamine, 4,4'-diamino-2,2'-bis(trifluoromethyl)biphenyl, 4,4'-diamino-2,2'-dimethylbiphenyl, 4,4'-diaminodiphenyl ether, 3,3'-diaminodiphenyl ether, 3,4'-diaminodiphenyl ether, 1,5-diaminonaphthalene, 4-aminophenyl-4-aminobenzoate, 4,4'-diaminobenzanilide, diaminodiphenyl sulfone, 4,4'-diaminodiphenyl Sulfide, 3,4'-diaminodiphenyl sulfide, 3,3'-diaminodiphenyl sulfide, 4,4'-diaminobiphenyl, 3,4'-diaminobiphenyl, 3,3'-diaminobiphenyl, 4,4'-diaminobenzophenone, 3,4'-diaminobenzophenone, 3,3'-diaminobenzophenone, 4,4'-diaminodiphenylmethane, 3,4'-diaminodiphenylmethane, 3,3'-diaminodiphenylmethane, 1,4-bis(4-aminophenoxy)benzene, 1,3-bis(4-aminophenoxy)benzene , 1,3-bis(3-aminophenoxy)benzene, bis[4-(4-aminophenoxy)phenyl]sulfone, bis{4-(3-aminophenoxy)phenyl}sulfone, 4,4-bis(4-aminophenoxy)biphenyl, 4,4-bis(3-aminophenoxy)biphenyl, bis[4-(4-aminophenoxy)phenyl]ether, bis[4-(3-aminophenoxy)phenyl]ether, 1,4-bis(4-aminophenyl)benzene, 1,3-bis(4-aminophenyl)benzene, 9,10-bis(4-aminophenyl) Examples include anthracene, 2,2-bis(4-aminophenyl)propane, 3,3'-diaminobenzophenone, 4,4'-diaminobenzophenone, 2,2-bis(4-aminophenyl)hexafluoropropane, 2,2-bis[4-(4-aminophenoxy)phenyl]propane, 2,2-bis[4-(4-aminophenoxy)phenyl]hexafluoropropane, 1,4-bis(3-aminopropyldimethylsilyl)benzene, and 9,9-bis(4-aminophenyl)fluorene, which can be used individually or in combination.Depending on the required physical properties of the application field, an appropriate diamine component can be selected and used.

[0045] When obtaining a polyimide resin with low dielectric properties, it is preferable to use one or more diamines selected from the above diamine components, specifically p-phenylenediamine, 4,4'-diamino-2,2'-bis(trifluoromethyl)biphenyl, 4,4'-diamino-2,2'-dimethylbiphenyl, diaminodiphenylsulfone, 1,4-bis(4-aminophenoxy)benzene, 1,3-bis(4-aminophenoxy)benzene, 1,3-bis(3-aminophenoxy)benzene, 2-bis[4-(4-aminophenoxy)phenyl]hexafluoropropane, 1,4-bis(3-aminopropyldimethylsilyl)benzene, and 9,9-bis(4-aminophenyl)fluorene, in combination.

[0046] <Method for producing polyamic acid> Polyamic acid, a precursor of the above-mentioned polyimide resin, can be produced by known general methods. For example, a polyamic acid solution can be obtained by reacting (addition polymerization) a tetracarboxylic dianhydride component with a diamine component in an organic solvent.

[0047] In the production of polyamic acid, it is preferable to use a polar organic solvent in terms of its solubility with polyamic acid. Specific examples of solvents include N,N-dimethylformamide, N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, N,N-dimethylacetamide, dimethyl sulfoxide, diethylene glycol dimethyl ether, cyclopentanone, γ-butyrolactone, α-acetyl-γ-butyrolactone, tetramethylurea, 1,3-dimethyl-2-imidazolinone, N-cyclohexyl-2-pyrrolidone, and 2-octanone, which can be used individually or in combination of two or more.

[0048] The molecular weight of polyamic acid can be adjusted by adjusting the ratio of the total number of moles of the tetracarboxylic dianhydride component to the total number of moles of the diamine component. The monomer components used in the production of polyamic acid may include components other than the tetracarboxylic dianhydride and diamine components. For example, monofunctional amines or monofunctional acid anhydrides may be used for purposes such as adjusting the molecular weight.

[0049] The production of polyamic acid by reaction of a tetracarboxylic dianhydride component and a diamine component is preferably carried out in an inert atmosphere such as argon or nitrogen. Polymerization proceeds by dissolving the tetracarboxylic dianhydride component and the diamine component in an organic solvent and mixing them in an inert atmosphere. The order of addition of the tetracarboxylic dianhydride component and the diamine component is not particularly limited. For example, the diamine component may be dissolved in an organic solvent or dispersed in a slurry to form a diamine solution, and the tetracarboxylic dianhydride component may be added to the diamine solution. The tetracarboxylic dianhydride component may be added in a solid state, or it may be added dissolved in an organic solvent or dispersed in a slurry.

[0050] The reaction temperature conditions are not particularly limited. From the viewpoint of suppressing the decrease in molecular weight of polyamic acid due to depolymerization, the maximum temperature during the polyaddition reaction should be 60°C or lower. From the viewpoint of allowing the polymerization reaction to proceed appropriately, a reaction temperature of 0 to 50°C is more preferable. The reaction time can be arbitrarily set within the range of 10 minutes to 30 hours.

[0051] Furthermore, it is preferable to adjust the viscosity and other properties of the polyamic acid solution by adjusting the concentration of polyamic acid (solid content concentration of the solution) before use.

[0052] Various organic or inorganic low-molecular-weight or high-molecular-weight compounds may be added to polyamic acid and polyimide to impart processing properties and various functionalities. For example, the polyamic acid solution may contain dyes, surfactants, leveling agents, plasticizers, fine particles, sensitizers, silane coupling agents, nucleating agents, etc. The fine particles may be either organic or inorganic, and may have a porous or hollow structure.

[0053] <Method for producing polyimide resins> The above-mentioned polyimide resin is produced by imidizing polyamic acid by dehydration and ring closure. Generally, imidization methods are broadly classified into thermal imidization and chemical imidization. Thermal imidization is a method in which imidization is promoted by casting a polyamic acid solution onto a substrate as a film-forming dope and heating, without using dehydration and ring-closing agents. Chemical imidization, on the other hand, is a method in which imidization is promoted by using a film-forming dope prepared by adding at least one of a dehydration and ring-closing agent and an imidization catalyst as an imidization accelerator to a polyamic acid solution. Either method may be used in the present invention.

[0054] Dehydrating ring-closing agents are those that have a dehydrating ring-closing effect on polyamic acid, and aliphatic acid anhydrides, aromatic acid anhydrides, N,N'-dialkylcarbodiimides, lower aliphatic halides, halogenated lower aliphatic acid anhydrides, aryl sulfonic acid dihalides, thionyl halides, or mixtures of two or more of these can be preferably used. Among these, aliphatic acid anhydrides and aromatic acid anhydrides work more effectively. Acetic anhydride is particularly preferred. The preferred amount of dehydrating reagent to introduce is 0.5 to 4.0 moles, preferably 0.7 to 4.0 moles, and particularly preferably 1.0 to 4.0 moles, per mole of amide acid units in the polyamic acid contained in the solution.

[0055] An imidation catalyst is a catalyst that promotes the dehydration and cyclization action of a dehydration cyclization agent on polyamic acid, and can be an aliphatic tertiary amine, an aromatic tertiary amine, or a heterocyclic tertiary amine. Of these, nitrogen-containing heterocyclic compounds such as pyridine, imidazole, benzimidazole, isoquinoline, quinoline, or pyridine compounds in which alkyl groups are substituted at the β and / or γ positions are preferred. In particular, pyridine, isoquinoline, or pyridine compounds in which alkyl groups are substituted at the β and / or γ positions are preferred. A suitable amount of imidation catalyst to introduce is 0.05 to 2.0 moles, preferably 0.1 to 2.0 moles, and particularly preferably 0.2 to 2.0 moles, per mole of amide acid units in the polyamic acid contained in the solution containing the imidation catalyst.

[0056] When adding at least one of the dehydrating cyclizing agent and the imidation catalyst to a polyamic acid solution, they may be added directly without dissolving in an organic solvent, or they may be added after being dissolved in an organic solvent. In the method of adding them directly without dissolving in an organic solvent, the reaction may proceed rapidly before at least one of the dehydrating cyclizing agent and the imidation catalyst diffuses, and a gel may form. Therefore, it is preferable to add a solution obtained by dissolving at least one of the dehydrating cyclizing agent and the imidation catalyst in an organic solvent (imidation accelerator) to the polyamic acid solution.

[0057] The above-mentioned polyimide resin can be manufactured by applying a polyamic acid solution and imidizing it. When using a polyimide resin as the interlayer insulating film of the present invention, a film can be formed by applying a polyamic acid solution and imidizing it, or the applied and imidized film can be attached to another substrate by lamination or other methods.

[0058] <Protective layer> The protective layer of the present invention will be described in detail below. The protective layer of the present invention is formed by coating and patterning a polysiloxane photosensitive resin composition onto an interlayer insulating film. The protective layer functions as a mask (dry etching resist) when patterning the interlayer insulating film by dry etching. In areas where the protective layer is provided, the interlayer insulating film is not etched, while the interlayer insulating film below openings where the protective layer is not provided is etched.

[0059] The thickness of the protective layer in this invention should be set so that the protective layer remains intact when the interlayer insulating film is etched by dry etching. If the etching rate of the protective layer in dry etching is sufficiently small compared to the interlayer insulating film, the protective layer will function as a dry etching resist even if its thickness is small.

[0060] From the viewpoint of improving patterning accuracy, the thickness of the protective layer is preferably 5 μm or less, more preferably 3 μm or less, and even more preferably 2 μm or less. Note that this thickness refers to the thickness of the layer before patterning by dry etching is performed.

[0061] The protective layer of the present invention is formed from a polysiloxane photosensitive resin composition and therefore contains silicon atoms. From the viewpoint of reducing the dry etching rate, the silicon atom content is preferably 10% by weight or more, and more preferably 12% by weight or more. The silicon atom content can be quantified by X-ray electron spectroscopy (XPS).

[0062] <Polysiloxane photosensitive resin composition> The polysiloxane photosensitive resin composition of the present invention is a photosensitive resin composition that can be patterned by photolithography, and contains a polysiloxane resin containing a polysiloxane structure as a binder resin. A polysiloxane structure means a structural skeleton having siloxane units Si-O-Si. The polysiloxane structure may be a cyclic polysiloxane structure. A "cyclic polysiloxane structure" means a cyclic molecular structural skeleton having siloxane units (Si-O-Si) as ring components.

[0063] The polymer may contain a polysiloxane structure in the main chain or in the side chains. When the polymer contains a polysiloxane structure in the main chain, its etching resistance tends to improve in particular.

[0064] <Polysiloxane resin> Polysiloxane resins can be obtained, for example, by a hydrosilylation reaction between a polysiloxane compound having (α) at ​​least two SiH groups in one molecule and a compound having (β) at least two carbon-carbon double bonds (ethylenically unsaturated groups) in one molecule that are reactive with SiH groups. The reaction between a compound (α) having multiple SiH groups and a compound having multiple ethylenically unsaturated groups results in crosslinking of multiple compounds (α), which tends to increase the molecular weight of the polymer and improve film-forming properties and etching resistance of the resin film.

[0065] (Compound (α): Polysiloxane compound having a SiH group) Specific examples of polysiloxane compounds (α) having at least two SiH groups in one molecule include linear hydrosilyl group-containing polysiloxanes, polysiloxanes having hydrosilyl groups at the molecular ends, and cyclic polysiloxanes containing hydrosilyl groups. Polymers containing cyclic polysiloxane structures tend to have superior film-forming properties and etching resistance compared to polymers containing only linear polysiloxane structures.

[0066] The cyclic polysiloxane may have a polycyclic structure, and the polycyclic structure may have a polyhedral structure. To form a film with high heat resistance and mechanical strength, it is preferable to use a cyclic polysiloxane compound having at least two SiH groups in one molecule as compound (α). Compound (α) preferably contains three or more SiH groups in one molecule. From the viewpoint of heat resistance and light resistance, it is preferable that the group present on the Si atom is either a hydrogen atom or a methyl group.

[0067] Examples of the hydrosilyl group-containing polysiloxane having a linear structure include a copolymer of dimethylsiloxane units, methylhydrogensiloxane units, and terminal trimethylsiloxy units; a copolymer of diphenylsiloxane units, methylhydrogensiloxane units, and terminal trimethylsiloxy units; a copolymer of methylphenylsiloxane units, methylhydrogensiloxane units, and terminal trimethylsiloxy units; and polysiloxane blocked at the terminals with dimethylhydrogensilyl groups.

[0068] Examples of the polysiloxane having a hydrosilyl group at the molecular terminals include polysiloxane blocked at the terminals with dimethylhydrogensilyl groups, and polysiloxane composed of dimethylhydrogensiloxane units (H(CH3)2SiO 1 / 2 units), and at least one siloxane unit selected from the group consisting of SiO2 units, SiO 3 / 2 units, and SiO units.

[0069] The cyclic polysiloxane is represented by, for example, the following general formula (III).

[0070] [Chemical formula]

[0071] In the formula, R 4 , R 5 and R 6 each independently represent an organic group having 1 to 20 carbon atoms. m represents an integer of 2 to 10, and n represents an integer of 0 to 10. m is preferably 3 or more. m + n is preferably 3 to 12.

[0072] R 4 , R 5 and R 6 are preferably organic groups composed of elements selected from the group consisting of C, H, and O. R 4 , R 5 and R 6Examples include alkyl groups, hydroxyalkyl groups, alkoxyalkyl groups, oxyalkyl groups, and aryl groups. Among these, chain alkyl groups such as methyl, ethyl, propyl, hexyl, octyl, decyl, and dodecyl groups, cyclic alkyl groups such as cyclohexyl and norbornyl groups, or phenyl groups are preferred. From the viewpoint of the availability of compound (β), R 4 , R 5 and R 6 It is preferable that the group is a methyl group, a propyl group, a hexyl group, or a phenyl group. 4 and R 5 It is more preferably a chain-like alkyl group having 1 to 6 carbon atoms, and a methyl group is particularly preferred.

[0073] Examples of cyclic polysiloxane compounds represented by general formula (III) include 1,3,5,7-tetrahydrogen-1,3,5,7-tetramethylcyclotetrasiloxane, 1-propyl-3,5,7-trihydrogen-1,3,5,7-tetramethylcyclotetrasiloxane, 1,5-dihydrogen-3,7-dihexyl-1,3,5,7-tetramethylcyclotetrasiloxane, 1,3,5-trihydrogen-1,3,5-trimethylcyclosiloxane, 1,3,5,7,9-pentahydrogen-1,3,5,7,9-pentamethylcyclosiloxane, and 1,3,5,7,9,11-hexahydrogen-1,3,5,7,9,11-hexamethylcyclosiloxane. In particular, from the viewpoint of availability and the reactivity of the SiH group, 1,3,5,7-tetrahydrogen-1,3,5,7-tetramethylcyclotetrasiloxane (in general formula (III), m=4, n=0, R 4 Compounds in which the group is a methyl group are preferred.

[0074] Compound (α) may be a polycyclic polysiloxane. The polycyclic structure may be a polyhedral structure. Polysiloxanes having a polyhedral skeleton preferably have 6 to 24 Si atoms constituting the polyhedral skeleton, and more preferably 6 to 10. A specific example of a polysiloxane having a polyhedral skeleton is silsesquioxane (number of Si atoms = 8) represented by the following general formula (IV).

[0075] [ka]

[0076] In the above formula, R 10 ~R 17 Each of these groups is independently selected from a hydrogen atom, a linear alkyl group (methyl, ethyl, propyl, and butyl groups, etc.), a cycloalkyl group (cyclohexyl, etc.), an aryl group (phenyl and tolyl groups, etc.), a group in which some or all of the hydrogen atoms bonded to the carbon atoms of these groups are substituted with halogen atoms or cyano groups, etc. (chloromethyl, trifluoropropyl, and cyanoethyl groups, etc.), an alkenyl group (vinyl, allyl, butenyl, and hexenyl groups, etc.), a (meth)acryloyl group, an epoxy group, and an organic group containing a mercapto or amino group, and is a monovalent group. The number of carbon atoms in the above hydrocarbon group is preferably 1 to 20, more preferably 1 to 10. The cyclic polysiloxane having a polyhedral skeleton has two or more hydrosilyl groups, which are reactive groups in the hydrosilylation reaction. Therefore, R 10 ~R 17 At least two of them are hydrogen atoms.

[0077] To achieve high dry etching resistance (slowing down the dry etching rate), it is desirable that the polysiloxane photosensitive resin composition contains a compound having the structure shown in formula III or formula IV above.

[0078] (Compound (β): Compound containing an ethylenically unsaturated group) Compound (β) contains two or more carbon-carbon double bonds in one molecule that are reactive with SiH groups. Examples of groups containing carbon-carbon double bonds that are reactive with SiH groups (hereinafter sometimes simply referred to as "ethylenically unsaturated groups" or "alkenyl groups") include vinyl groups, allyl groups, metharyl groups, acrylic groups, methacrylic groups, 2-hydroxy-3-(allyloxy)propyl groups, 2-allylphenyl groups, 3-allylphenyl groups, 4-allylphenyl groups, 2-(allyloxy)phenyl groups, 3-(allyloxy)phenyl groups, 4-(allyloxy)phenyl groups, 2-(allyloxy)ethyl groups, 2,2-bis(allyloxymethyl)butyl groups, 3-allyloxy-2,2-bis(allyloxymethyl)propyl groups, and vinyl ether groups.

[0079] Specific examples of compounds (β) having two or more alkenyl groups in one molecule include diallyl phthalate, triallyl trimellitate, diethylene glycol bisallyl carbonate, trimethylolpropane diallyl ether, trimethylolpropane triallyl ether, pentaerythritol triallyl ether, pentaerythritol tetraallyl ether, 1,1,2,2-tetraallyloxyethane, diarylidene pentaerythritol, triallyl cyanurate, triallyl isocyanurate, diallyl monobenzyl isocyanurate, diallyl monomethyl isocyanurate, 1,2,4-trivinylcyclohexane, 1,4-butanediol divinyl ether, nonanediol divinyl ether, 1,4-cyclohexane dimethanol divinyl ether, triethylene glycol divinyl ether, trimethylolpropane trivinyl ether, and pentaerythritol tetravinyl ether. Examples include epoxy resins, diallyl ethers of bisphenol S, divinylbenzene, divinylbiphenyl, 1,3-diisopropenylbenzene, 1,4-diisopropenylbenzene, 1,3-bis(allyloxy)adamantane, 1,3-bis(vinyloxy)adamantane, 1,3,5-tris(allyloxy)adamantane, 1,3,5-tris(vinyloxy)adamantane, dicyclopentadiene, vinylcyclohexene, 1,5-hexadiene, 1,9-decadien, diallyl ethers, bisphenol A diallyl ether, 2,5-diallylphenol allyl ether, and their oligomers, 1,2-polybutadiene (with a 1,2 ratio of 10-100%, preferably 50-100%), allyl ethers of novolacphenol, allylated polyphenylene oxide, and other conventionally known epoxy resins in which all glycidyl groups have been replaced with allyl groups. Furthermore, compounds obtained by replacing the allyl group in the above example compounds with a (meth)acryloyl group (for example, polyfunctional (meth)acrylates) can also be suitably used as compound (β).

[0080] Compound (β) may be a polysiloxane compound having two or more alkenyl groups. Specific examples of cyclic polysiloxane compounds having two or more alkenyl groups include 1,3,5,7-tetravinyl-1,3,5,7-tetramethylcyclotetrasiloxane, 1-propyl-3,5,7-trivinyl-1,3,5,7-tetramethylcyclotetrasiloxane, 1,5-divinyl-3,7-dihexyl-1,3,5,7-tetramethylcyclotetrasiloxane, 1,3,5-trivinyl-1,3,5-trimethylcyclosiloxane, 1,3,5,7,9-pentavinyl-1,3,5,7,9-pentamethylcyclosiloxane, and 1,3,5,7,9,11-hexavinyl-1,3,5,7,9,11-hexamethylcyclosiloxane.

[0081] Compound (β) may be a compound having alkenyl groups at the terminal and / or side chains of polymer chains such as polyethers, polyesters, polyarylates, polycarbonates, polyolefins, polyacrylic acid esters, polyamides, polyimides, and phenol-formaldehyde.

[0082] (Other starting materials) In addition to the above compounds (α) and (β), a compound containing only one functional group involved in the hydrosilylation reaction may be used as a starting material for the hydrosilylation reaction. The functional group involved in the hydrosilylation reaction is either a SiH group or an ethylenically unsaturated group. By using a compound containing only one functional group involved in the hydrosilylation reaction, a specific functional group can be introduced to the ends of the polymer.

[0083] Compounds having photopolymerizable functional groups may be used as starting materials for the hydrosilylation reaction. Examples of photopolymerizable functional groups include cationic polymerizable functional groups and radical polymerizable functional groups. A "cationic polymerizable functional group" refers to a functional group that polymerizes and crosslinks with an acidic active substance generated from a photoacid generator when irradiated with active energy rays. Examples of active energy rays include visible light, ultraviolet rays, infrared rays, X-rays, alpha rays, beta rays, and gamma rays. Examples of cationic polymerizable functional groups include epoxy groups, vinyl ether groups, oxetane groups, and alkoxysilyl groups. From the viewpoint of photosensitivity, epoxy groups are preferred as cationic polymerizable functional groups, and among epoxy groups, alicyclic epoxy groups or glycidyl groups are preferred from the viewpoint of stability. In particular, alicyclic epoxy groups are preferred because they have excellent photocationic polymerizability.

[0084] Specific examples of compounds having an alkenyl group and an epoxy group as a cationic polymerizable functional group in a single molecule include vinylcyclohexene oxide, allyl glycidyl ether, diallyl monoglycidyl isocyanurate, and monoallyl diglycidyl isocyanurate.

[0085] Polysiloxane resins may be alkali-soluble. Alkali solubility can be imparted to the resin by introducing alkali-solubility-imparting groups. When a resin has both photopolymerizable functional groups and alkali-soluble groups, it exhibits solubility in alkali before photocuring and becomes alkali-insoluble after photocuring, thus it can be used as a negative-type photosensitive resin. Furthermore, by combining an alkali-soluble resin with a photosensitive material such as a quinone diazide compound, a positive-type photosensitive resin composition can be obtained.

[0086] Examples of alkali-solubility-imparting groups include isocyanuric acid derivative structures represented by X1 or X2 below, phenolic hydroxyl groups, and carboxyl groups. From the viewpoint of resolution during patterning, it is preferable that compound (A) has a structure represented by the above formula X1 or X2 as an alkali-solubility group. By using a compound containing an acidic group and an alkenyl group and / or a SiH group as a starting material for the hydrosilylation reaction, an alkali-solubility-imparting polysiloxane resin can be obtained.

[0087] [ka]

[0088] Polysiloxane polymers may exhibit alkali solubility in the presence of acid due to the detachment of protective groups. Polymers that exhibit alkali solubility in the presence of acid due to the detachment of protective groups can be used as positive-type photosensitive resins because their protective groups are removed (deprotected) by reaction with the acid generated from a photoacid generator, increasing their alkali solubility.

[0089] (Hydrosilylation reaction) The order and method of the hydrosilylation reaction are not particularly limited. The hydrosilylation reaction may be carried out by charging all the starting materials in a single pot and performing polymerization, or the starting materials may be added in multiple stages and the reaction may be carried out in multiple steps.

[0090] Hydrosilylation catalysts such as chloroplatinic acid, platinum-olefin complexes, and platinum-vinylsiloxane complexes may be used in the hydrosilylation reaction. A hydrosilylation catalyst and a co-catalyst may also be used in combination. The amount of hydrosilylation catalyst added is not particularly limited, but preferably 10 times the total amount (in moles) of alkenyl groups contained in the starting material. -8 ~10 -1 double, more comfortable 10 -6 ~10 -2 It is double.

[0091] The reaction temperature for hydrosilylation can be set appropriately, preferably 30 to 200°C, and more preferably 50 to 150°C. The oxygen volume concentration in the gas phase during the hydrosilylation reaction is preferably 3% or less. From the viewpoint of promoting the hydrosilylation reaction by adding oxygen, the gas phase may contain about 0.1 to 3% by volume of oxygen.

[0092] A solvent may be used in the hydrosilylation reaction. Examples of solvents include hydrocarbon solvents such as benzene, toluene, hexane, and heptane; ether solvents such as tetrahydrofuran, 1,4-dioxane, 1,3-dioxolane, and diethyl ether; ketone solvents such as acetone and methyl ethyl ketone; and halogen solvents such as chloroform, methylene chloride, and 1,2-dichloroethane. Toluene, tetrahydrofuran, 1,4-dioxane, 1,3-dioxolane, or chloroform are preferred because they are easily removed by distillation after the reaction. A gelation inhibitor may be used in the hydrosilylation reaction as needed.

[0093] The polysiloxane photosensitive resin composition of the present invention may contain, in addition to the above-mentioned polysiloxane resin, a photoacid generator, a sensitizer, a quinone diazide compound, a solvent, and the like.

[0094] <Photoacid Generator> The polysiloxane photosensitive resin composition of the present invention may contain a photoacid generator. When the photoacid generator is irradiated with active energy rays such as ultraviolet light, acid is generated. In cationic polymerizable compositions (for example, negative-type photosensitive compositions), the photoacid generator acts as a polymerization initiator, and curing by cationic polymerization proceeds. In chemically amplified positive-type photosensitive compositions, the acid generated from the photoacid generator causes protective groups bonded to alkali-solubility-granting groups (acidic groups) to detach, increasing alkali solubility.

[0095] The photoacid generator included in the polysiloxane photosensitive resin composition is not particularly limited as long as it generates Lewis acid upon exposure. Specific examples of photoacid generators include ionic photoacid generators such as sulfonium salts, iodonium salts, ammonium salts, and other onium salts; and nonionic photoacid generators such as imidosulfonates, oximesulfonates, and sulfonyldiazomethanes.

[0096] The amount of photoacid generator in the polysiloxane photosensitive resin composition is preferably 0.1 to 20 parts by weight, more preferably 0.1 to 15 parts by weight, and even more preferably 0.5 to 10 parts by weight, per 100 parts by weight of the resin content of the composition.

[0097] <Sensitizer> The polysiloxane photosensitive resin composition of the present invention may contain a sensitizer. The use of a sensitizer improves the exposure sensitivity during patterning. Examples of sensitizers include naphthalene compounds, anthracene compounds, and thioxanthone compounds, among which anthracene sensitizers are preferred due to their excellent photosensitizing effect. Specific examples of anthracene-based sensitizers include anthracene, 2-ethyl-9,10-dimethoxyanthracene, 9,10-dimethylanthracene, 9,10-dibutoxyanthracene (DBA), 9,10-dipropoxyanthracene, 9,10-diethoxyanthracene, 9,10-bis(octanoyloxy)anthracene, 1,4-dimethoxyanthracene, 9-methylanthracene, 2-ethylanthracene, 2-tert-butylanthracene, 2,6-di-tert-butylanthracene, and 9,10-diphenyl-2,6-di-tert-butylanthracene.

[0098] The amount of sensitizer in the composition is not particularly limited and can be adjusted as appropriate within a range that can exert a sensitizing effect. From the viewpoint of balancing the curability and physical properties of the resin film, 0.01 to 20 parts by weight, more preferably 0.1 to 15 parts by weight, and even more preferably 0.5 to 10 parts by weight per 100 parts by weight of resin in the composition is preferred.

[0099] <Quinone diazide compounds> The polysiloxane photosensitive resin composition of the present invention may contain a quinone diazide compound. By combining it with a polysiloxane resin to which alkali solubility has been imparted, positive patterning properties are exhibited. There are no particular restrictions on the quinone diazide compound, and any known compound used as a photosensitive agent in the resist field can be used. Two or more quinone diazide compounds may be used in combination. Examples of quinone diazide compounds include esters of a phenol compound with 1,2-benzoquinone diazide-4-sulfonic acid or 1,2-benzoquinone diazide-5-sulfonic acid, and esters of a phenol compound with 1,2-naphthoquinone diazide-4-sulfonic acid or 1,2-naphthoquinone diazide-5-sulfonic acid.

[0100] In the polysiloxane photosensitive resin composition of the present invention, the content of the quinone diazide compound is preferably 1 to 30 parts by weight, more preferably 3 to 20 parts by weight, and even more preferably 5 to 15 parts by weight, per 100 parts by weight of the component excluding the solvent.

[0101] <Solvent> A polysiloxane photosensitive resin composition can be prepared by dissolving or dispersing each of the above components in a solvent. The solvent can be any solvent capable of dissolving the polysiloxane resin and other components, and specifically includes hydrocarbon solvents such as benzene, toluene, hexane, and heptane; ether solvents such as tetrahydrofuran, 1,4-dioxane, 1,3-dioxolane, and diethyl ether; ketone solvents such as acetone, methyl ethyl ketone, methyl isobutyl ketone, and cyclohexanone; glycol solvents such as propylene glycol-1-monomethyl ether-2-acetate (PGMEA), diethylene glycol dimethyl ether, diethylene glycol ethyl methyl ether, and ethylene glycol diethyl ether; and halogen solvents such as chloroform, methylene chloride, and 1,2-dichloroethane. From the viewpoint of film formation stability, propylene glycol-1-monomethyl ether-2-acetate is preferred. The amount of solvent used can be set as appropriate.

[0102] <Other ingredients> Polysiloxane photosensitive resin compositions may contain resin components and additives other than those listed above. For example, they may contain thermoplastic resins, adhesion modifiers, coupling agents such as silane coupling agents, degradation inhibitors, hydrosilylation reaction inhibitors, polymerization inhibitors, polymerization catalysts (crosslinking accelerators), mold release agents, flame retardants, flame retardant aids, surfactants, defoamers, emulsifiers, leveling agents, anti-repellency agents, ion trapping agents, thixotropic agents, tackifiers, storage stability modifiers, light stabilizers, thickeners, plasticizers, reactive diluents, antioxidants, thermal stabilizers, conductivity modifiers, antistatic agents, radiation shielding agents, nucleating agents, phosphorus-based peroxide decomposers, lubricants, metal deactivators, thermal conductivity modifiers, and property modifiers.

[0103] <Photolithography> The polysiloxane photosensitive resin composition of the present invention forms a protective layer patterned by photolithography. The photolithography method is described below. The coating method is not particularly limited as long as it allows for uniform application, and commonly used methods such as spin coating and slit coating can be used.

[0104] As the exposure light source, any light source that emits light at the absorption wavelength of the photoacid generator or quinone diazide compound used can be used. Typically, light sources with wavelengths in the range of 300 to 450 nm can be used, such as high-pressure mercury lamps, ultra-high-pressure mercury lamps, metal halide lamps, high-power metal halide lamps, xenon lamps, carbon arc lamps, and light-emitting diodes. The exposure dose is not particularly limited, but a preferred exposure dose range is 1 to 1000 mJ / cm². 2 , more preferably 1 to 500 mJ / cm² 2 That is the case.

[0105] Furthermore, pre-baking or vacuum defloration processes can be performed before exposure to remove solvents. However, due to issues such as reduced developability caused by heat, the pre-baking temperature is preferably 130°C or lower, and more preferably 120°C or lower. Vacuum defloration and heating can also be performed simultaneously.

[0106] There are no particular restrictions on the development method; the exposed areas can be dissolved and removed to form the desired pattern using commonly used development methods such as immersion or spraying. As for the developer, any commonly used developer can be used without particular restrictions. Specific examples include organic alkaline aqueous solutions such as tetramethylammonium hydroxide aqueous solution and choline aqueous solution, inorganic alkaline aqueous solutions such as potassium hydroxide aqueous solution, sodium hydroxide aqueous solution, potassium carbonate aqueous solution, sodium carbonate aqueous solution, and lithium carbonate aqueous solution, as well as solutions to which alcohol or surfactants have been added to adjust the dissolution rate, and various organic solvents.

[0107] <Dry etching> Dry etching is performed on a laminate in which a patterned protective layer is provided on an interlayer insulating film. Since the protective layer functions as a dry etching resist, the interlayer insulating film is not etched in the areas where the protective layer is present, and the interlayer insulating film below openings where the protective layer is not present is removed by etching. This forms a patterned interlayer insulating film.

[0108] Dry etching is a method of etching materials using reactive gases, ions, or radicals, and includes reactive gas etching, reactive ion etching (RIE), and reactive ion beam etching (ion milling). RIE is particularly preferred because it offers high processability for resin materials.

[0109] For dry etching, the etching gas can be oxygen gas, oxygen-containing gases such as carbon monoxide and carbon dioxide; hydrocarbon gases; hydrogen gas; ammonia gas; chlorine-based gases such as chlorine and boron chloride; fluorine-based gases; or noble gases such as argon and helium. Among these, oxygen gas, hydrocarbon gases, or noble gases are preferred as etching gases because they allow for a lower etching rate of the protective layer made of polysiloxane photosensitive resin and improve etching selectivity.

[0110] For the formation of fine wiring patterns, it is advantageous to minimize the thickness of the protective layer, and it is preferable that the ratio (selectivity ratio) of the etching rate of the interlayer insulating film to the etching rate of the protective layer by dry etching is large. The etching rate of the protective layer is preferably 1 / 2 or less of the etching rate of the interlayer insulating film, more preferably 1 / 3 or less, and even more preferably 1 / 5 or less. The etching rate is the amount of change in film thickness per unit time and can be calculated from the amount of change in film thickness when dry etching is performed for a predetermined time.

[0111] <Removal of protective layer> The protective layer of the present invention is formed by dry etching, which creates an interlayer insulating film, and then peels it off and removes it. The method of peeling is not particularly limited, and any known method for peeling resists can be used. For example, immersion methods using organic solvents or alkaline aqueous solutions, spray methods, or dry etching methods can be used. In particular, when performing peeling by dry etching, selecting an etching gas such as a fluorine-based gas or a chlorine-based gas, which tends to increase the etching rate of polysiloxane photosensitive resins, allows for processing in a short time. [Examples]

[0112] The present invention will be described in detail below based on examples, but the present invention is not limited to the following examples.

[0113] <Synthesis of polysiloxane resin> (Synthesis Example 1) 20 g of toluene and 3 g of 1,3,5,7-tetramethylcyclotetrasiloxane were placed in a 100 mL four-necked flask, the gas phase was purged with nitrogen, and the mixture was heated and stirred at an internal temperature of 100°C. A mixture of 2 g of diallyl isocyanuric acid, 3 g of diallyl monomethyl isocyanurate, 0.7 mg of a xylene solution of a platinum vinylsiloxane complex (containing 3 wt% platinum), and 5 g of toluene was added. 1 After confirming the disappearance of peaks originating from the vinyl group by 1H-NMR, 1 g of vinylcyclohexene oxide was added at an internal temperature of 80°C. 1 After confirming the disappearance of peaks originating from the vinyl group by 1H-NMR, toluene was removed by distillation under reduced pressure to obtain a colorless, transparent liquid, "polysiloxane resin A".

[0114] <Preparation of Polysiloxane Photosensitive Resin Composition> Polysiloxane photosensitive resin compositions 1 and 2, and a polysiloxane-free photosensitive resin composition 3 were prepared using the formulations (weight ratios) shown in Table 1. Composition 1 is a positive-type polysiloxane photosensitive resin composition, composition 2 is a negative-type polysiloxane photosensitive resin composition, and composition 3 is a negative-type photosensitive resin composition made of acrylic resin.

[0115] Composition 3 is a composition containing, as a resin component, an alkali-soluble acrylic resin (Follet ZAH110, manufactured by Soken Chemical Co., Ltd.) and an epoxy compound represented by the following formula (Celoxide 2021P, manufactured by Daicel Corporation).

[0116] [ka]

[0117] Details of each component shown in Table 1 are as follows: Quinone diazide compound A: ((4-{4-[1,1-bis(4-hydroxyphenyl)ethyl]-α,α-dimethylbenzyl}phenol and 1,2-naphthoquinone diazide-5-sulfonic acid (esterification rate 2.0)) Photoacid generator: Sunapro's "CPI210S" (sulfonium salt-based photoacid generator) Sensitizer: 9,10-dibutoxyanthracene Solvent: Propylene glycol monomethyl ether acetate

[0118] <Preparation of the solution for forming the interlayer insulating film> (Solution 1 for forming interlayer insulating film) (Synthesis Example 2) In a 500 mL glass flask, 164.05 g of N,N-dimethylformamide (DMF), 2.47 g of 1,3-bis(4-aminophenoxy)benzene (TPE-R), and 6.71 g of p-phenylenediamine (PDA) were added. While stirring the contents of the flask, 12.45 g of 3,3',4,4'-biphenyltetracarboxylic acid dianhydride (BPDA), 7.44 g of 4,4'-oxydiphthalic acid anhydride (ODPA), and 0.46 g of pyromellitic acid dianhydride (PMDA) were added. The contents of the flask were then stirred for 30 minutes. Next, while stirring the contents of the flask, a pre-prepared PMDA solution (solvent: DMF, amount of PMDA dissolved: 0.46 g, concentration of PMDA: 7.2 wt%) was added to the flask at a rate that did not cause a rapid increase in the viscosity of the flask contents for a predetermined time. Then, when the viscosity of the flask contents reached 1500 poise at a temperature of 23°C, the addition of the PMDA solution was stopped, and the flask contents were stirred for another hour to obtain polyamic acid P1. The obtained polyamic acid solution P1 had a solid content concentration of 15% by weight. The obtained polyamic acid solution P1 also had a viscosity of 1500-2000 poise at a temperature of 23°C.

[0119] Solution 1 for forming an interlayer insulating film was prepared by adding 23 g of an imidation accelerator consisting of a mixture of IQ and DMF (weight ratio: IQ / DMF = 1.8 / 21.2) to 20 g of the polyamic acid solution P1 obtained in Synthesis Example 2.

[0120] (Solution for forming interlayer insulating film 2) A polyimide photosensitive resin composition is prepared as a comparative example of the present invention for forming an interlayer insulating film. Since this composition has a positive-type patterning function, it forms a patterned interlayer insulating film without forming a protective layer or performing a dry etching process.

[0121] (Synthesis Example 3) Under a stream of dry nitrogen, 18.31 g (0.050 mol) of 2,2-bis(3-amino-4-hydroxyphenyl)hexafluoropropane, 5.01 g (0.025 mol) of 4,4'-diaminodiphenyl ether, and 1.24 g (0.005 mol) of 1,1,3,3-tetramethyl-1,3-bis(3-aminopropyl)disiloxane were dissolved in 240 g of N-methyl-2-pyrrolidone (NMP). 44.42 g (0.100 mol) of 4,4'-hexafluoroisopropylidene diphthalic acid dianhydride was added along with 20 g of NMP, and the mixture was reacted at 40°C for 1 hour. Then, a solution of 17.87 g (0.150 mol) of N,N-dimethylformamide dimethylacetal diluted with 30 g of NMP was added dropwise over 10 minutes. After the addition, the mixture was stirred at 40°C for 1 hour. After the reaction was complete, the solution was added to 5 L of water, and the solid precipitate was collected by filtration. The resin solid was dried in a vacuum dryer at 50°C for 72 hours to obtain polyamic acid solution P2.

[0122] 17.5 g of the obtained polyamic acid solution P2 and 2.5 g of quinone diazide compound A were added to 30 g of γ-butyrolactone to obtain interlayer insulating film formation solution 2.

[0123] <Confirmation of etching rate and setting of film thickness of photosensitive resin composition> Interlayer insulating film formation solution 1 was applied by spin coating, and then the coated film was heated at 110°C for 150 seconds and at 250°C for 30 minutes to form an interlayer insulating film. Dry etching was performed using an inductively coupled plasma reactive ion etching apparatus (Samco "RIE800") under the following conditions. The etching rate (nm / min) was calculated from the change in film thickness per unit time, and then the minimum etching time required to completely remove the interlayer insulating film, assuming a film thickness of 4.0 μm, was calculated. Gas type: Oxygen / Argon Gas flow rate: (Oxygen) 10 sccm / (Argon) 10 sccm Applied power: 200W

[0124] Next, photosensitive resin compositions 1 to 3 were applied to separate substrates by spin coating, and then the coated films were heated at 100°C for 120 seconds, followed by a 300 mJ / cm² test using a mask aligner (Mikasa "MA-10"). 2 Exposure was performed, followed by heating at 100°C for 30 minutes to form a protective layer. Then, dry etching was performed in the same manner as above. The etching rate was calculated from the change in film thickness per unit time. From this, the film thickness that would decrease in the minimum etching time required to remove the interlayer insulating film thickness of 4.0 μm calculated above was calculated, and 1.2 times that film thickness was set as the film thickness during semiconductor device manufacturing.

[0125] <Confirmation of silicon atomic weight> Similar to the section on "Confirmation of etching rate and setting of film thickness of photosensitive resin composition," a photosensitive resin composition was applied and fired to form a protective film, and the amount of silicon atoms in the protective layer was measured by elemental analysis using X-ray electron spectroscopy (XPS).

[0126] <Checking pattern resolution> Photosensitive resin compositions 1 to 3 were applied to the substrate by spin coating so that the film thickness after firing would be the same as the film thickness used in the manufacture of the semiconductor device described above. Next, the coated film was heated at 100°C for 120 seconds, and exposed to a photomask with a hole pattern (positive pattern for Example 1, negative pattern for Example 2, Comparative Examples 1 and 2, both with hole patterns ranging from 1 to 100 μm in 1 μm increments) using a mask aligner (Mikasa "MA-10"), developed with a 2.38% TMAH developer, and then fired at 100°C for 30 minutes.

[0127] Subsequent observation confirmed the presence of holes of the specified size that penetrated to the substrate. The above experiment was conducted in the range of exposure doses from 10 to 1000 mJ / cm2 and development times from 30 to 600 seconds, and the smallest hole pattern that could be formed within this range was defined as the pattern resolution of the photosensitive resin composition.

[0128] The polyimide photosensitive resin composition for forming the interlayer insulating film described above was also applied to a substrate by spin coating to achieve a film thickness of 4.0 μm after firing. Following similar heating, exposure, and development treatments, it was fired at 250°C for 30 minutes, and the pattern resolution was evaluated.

[0129] <Method for measuring the physical properties of interlayer insulating films> This document describes methods for measuring the dielectric loss tangent (Df) and coefficient of thermal expansion (CTE) of interlayer insulating films.

[0130] [Dielectric Loss Tangent (Df)] The dielectric loss tangent was measured using a network analyzer (Hewlett-Packard "8719C") and a cavity resonator perturbation dielectric constant measuring device (EM Lab "CP531"). Specifically, first, the interlayer insulating film deposited on the substrate was peeled off in the same manner as described in the section "Confirmation of etching rate and setting of film thickness of photosensitive resin composition," and cut into 2 mm × 100 mm pieces to prepare a sample for dielectric loss tangent measurement. Next, the measurement sample was left for 24 hours in an atmosphere of 23°C and 50% relative humidity, and then the dielectric loss tangent was measured using the network analyzer and the cavity resonator perturbation dielectric constant measuring device under the conditions of 23°C, 50% relative humidity, and a measurement frequency of 10 GHz.

[0131] [Coefficient of linear expansion (CTE)] Using a thermal analyzer (Hitachi High-Tech Science Corporation's "TMA / SS6100"), a film was formed on a substrate in the same manner as described in the section "Confirmation of etching rate and setting of film thickness of photosensitive resin composition." The exfoliated interlayer insulating film was heated from -10°C to 300°C at a heating rate of 10°C / min, and then cooled down to -10°C at a cooling rate of 40°C / min. Next, the sample was heated again to 300°C at a heating rate of 10°C / min, and the coefficient of linear expansion was determined from the amount of strain between 50°C and 250°C during the second heating cycle. The measurement conditions are shown below. Sample size: 3mm wide, 10mm long Load: 1g Measurement atmosphere: Air atmosphere

[0132] Table 2 shows the etching rate, minimum etching time, pattern resolution, dielectric loss tangent, and thermal expansion coefficient of the interlayer insulating film, as confirmed by the above evaluation. Table 1 shows the silicon atomic weight, etching rate, film thickness during semiconductor manufacturing, and pattern resolution of the photosensitive resin composition.

[0133] <Manufacturing of semiconductor devices> (Example 1) After the semiconductor chip with the completed preceding process was sealed with molding resin, the molded substrate was peeled off from the support substrate and inverted. Interlayer insulating film formation solution 1 was applied to the molded substrate by spin coating to a film thickness of 4.0 μm after firing. Next, the coated film was heated at 110°C for 150 seconds and then at 250°C for 30 minutes to form an interlayer insulating film. Subsequently, polysiloxane photosensitive resin composition 1 was applied on the interlayer insulating film by spin coating to the film thickness set above. Next, the coated film was heated at 100°C for 120 seconds, and exposure was performed through a photomask of the design pattern (designed so that the minimum line width was the pattern resolution of the photosensitive resin composition 1 confirmed above) using a mask aligner (Mikasa "MA-10"). Development was performed with 2.38% TMAH developer to form a hole pattern. Furthermore, heating was performed at 100°C for 30 minutes to form a patterned protective layer. Using an inductively coupled plasma reactive ion etching apparatus (Samco "RIE800"), dry etching was performed for 11.9 minutes, which is 1.1 times the minimum etching time for the interlayer insulating film, under the same conditions as in the section "Confirmation of etching rate and setting of film thickness of photosensitive resin composition," to form a patterned interlayer insulating film. Subsequently, the protective layer was removed by immersion in 80°C NMP. Then, copper wiring was formed by copper plating. The above process of forming the patterned interlayer insulating film and copper wiring was repeated three times to form a rewiring layer. After that, external connection terminals were formed to obtain a semiconductor device.

[0134] (Example 2, Comparative Example 1) A semiconductor device was manufactured in the same manner as in Example 1, except that the photosensitive resin composition was changed to photosensitive resin composition 2 and 3, respectively, and the photomask was changed to one designed to have a negative pattern and the pattern resolution of each photosensitive resin composition.

[0135] (Comparative Example 2) After sealing the semiconductor chip, which had completed the previous process, with molding resin, the molded substrate was peeled off from the support substrate and inverted. Interlayer insulating film formation solution 2 was then applied to the molded substrate by spin coating to achieve a film thickness of 4.0 μm after firing. Next, the coated film was heated at 100°C for 120 seconds, and exposure was performed through a photomask of the design pattern (designed so that the minimum line width was the pattern resolution of the interlayer insulating film formation solution confirmed above) using a mask aligner (Mikasa "MA-10"). Development was performed with 2.38% TMAH developer to form a hole pattern. Furthermore, heating was performed at 250°C for 30 minutes to form a patterned interlayer insulating film. Subsequently, copper wiring was formed by copper plating. The above process of forming the patterned interlayer insulating film and copper wiring was repeated three times to form a rewiring layer. After that, external connection terminals were formed to obtain a semiconductor device.

[0136] Table 3 shows the minimum pattern line width of the redistribution layer, the dielectric loss tangent of the interlayer insulating film, and the thermal expansion coefficient of the semiconductor devices obtained as described above in Examples 1 and 2 and Comparative Examples 1 and 2. The semiconductor devices according to the examples of the present invention have a small minimum pattern line width and high wiring density, and because the dielectric loss tangent is low, the transmission loss is low, and because the thermal expansion coefficient is low, errors such as substrate warping and cracking are less likely to occur. On the other hand, in Comparative Example 1, since a polysiloxane photosensitive resin composition is not used, the required film thickness is large, and as a result the pattern resolution is greatly inferior, resulting in a very large minimum pattern line width and low wiring density. In Comparative Example 2, since a polyimide photosensitive resin composition is used to form the interlayer insulating film, the dielectric loss tangent is large, resulting in high transmission loss, and furthermore, the thermal expansion coefficient is large, making it highly likely that the above errors will occur. Furthermore, the pattern resolution is also inferior, so the minimum pattern line width is also large.

[0137] [Table 1]

[0138] [Table 2]

[0139] [Table 3] [Explanation of symbols]

[0140] 1 Semiconductor device 2 Semiconductor chips 3. Mold resin 4 Redistribution layer 4a Interlayer insulating film 4b Wiring 5. External connection terminals

Claims

1. A method for manufacturing a semiconductor device having a semiconductor element and a redistribution layer consisting of wiring and an interlayer insulating film that electrically connects to the semiconductor element, The aforementioned redistribution layer A process for forming an interlayer insulating film with a film thickness in the range of 0.5 μm to 12 μm. A step of forming a film of a polysiloxane photosensitive resin composition on the interlayer insulating film, and forming a patterned protective layer by exposing and developing the film. A step of removing the interlayer insulating film exposed below the opening of the protective layer by dry etching to form at least one pattern having a line width in the range of 0.5 to 6.0 μm in the interlayer insulating film. A method for manufacturing a semiconductor device, characterized by being obtained by a process including a peeling step of peeling off a patterned protective layer.

2. The method for manufacturing a semiconductor device according to claim 1, wherein the dielectric loss tangent of the interlayer insulating film at 10 GHz is 0.0100 or less.

3. The method for manufacturing a semiconductor device according to claim 1, wherein the thermal expansion coefficient of the interlayer insulating film is 50 ppm / K or less.

4. The method for manufacturing a semiconductor device according to claim 1, characterized in that the interlayer insulating film contains a polyimide resin, a polybenzoxazole resin, a polyphenylene ether resin, a liquid crystalline resin, a polystyrene resin, or a polyolefin resin.

5. The method for manufacturing a semiconductor device according to claim 1, characterized in that the aspect ratio between the thickness of the interlayer insulating film and the minimum pattern line width (= thickness of the interlayer insulating film ÷ via diameter) is in the range of 1.0 to 10.

0.

6. The method for manufacturing a semiconductor device according to claim 1, wherein at least one of oxygen gas, noble gas, and hydrocarbon gas is used as the etching gas for dry etching of the interlayer insulating film.

7. The method for manufacturing a semiconductor device according to claim 1, wherein in the dry etching, the etching rate of the protective layer is 1 / 2 or less of the etching rate of the interlayer insulating film.

8. The method for manufacturing a semiconductor device according to claim 1, wherein the silicon atom content in the protective layer is 10% by weight or more.

9. The method for manufacturing a semiconductor device according to claim 1, characterized in that the polysiloxane photosensitive resin composition contains a compound having a structure represented by formula III or formula IV. (R in formula III) ４ , R ５ and R ６ Each of these independently represents an organic group with 1 to 20 carbon atoms. m is an integer from 2 to 10, and n is an integer from 0 to 10. Also, in formula IV, R １０ ~R １７ Each of these groups is independently selected from a range of monovalent groups, including hydrogen atoms, linear alkyl groups (methyl, ethyl, propyl, and butyl groups, etc.), cycloalkyl groups (cyclohexyl, etc.), aryl groups (phenyl and tolyl groups, etc.), groups in which some or all of the hydrogen atoms bonded to the carbon atoms of these groups are substituted with halogen atoms or cyano groups (chloromethyl, trifluoropropyl, and cyanoethyl groups, etc.), alkenyl groups (vinyl, allyl, butenyl, and hexenyl groups, etc.), (meth)acryloyl groups, epoxy groups, and organic groups containing mercapto or amino groups. 【Chemistry 1】 【Chemistry 2】

10. The method for manufacturing a semiconductor device according to claim 1, characterized in that the polysiloxane photosensitive resin contains a compound having a structure represented by X1 or X2 below. 【Transformation 3】

11. The interlayer insulating film is pyromellitic dianhydride, 3,3',4,4'-biphenyltetracarboxylic acid dianhydride, 4,4'-oxydiphthalic acid dianhydride, 3,3',4,4'-benzophenonetetracarboxylic acid dianhydride, 9,9-bis[4-(3,4-dicarboxyphenoxy)phenyl]fluorenidioanhydride, p-phenylenebis(trimellitate anhydride), 4,4'-bis(1,3-dioxo-1,3-dihydroisobenzofuran-5-ylcarbonyloxy)biphenyl, 4-[4-(1,3-dioxoisobenzofuran-5-ylcarbonyloxy)-2,3,5-trimethylphenyl]-2,3,6-trimethylphenyl1,3-dioxoisobenzo A method for manufacturing a semiconductor device according to claim 1, characterized in that the polyimide resin contains one or more tetracarboxylic acid dianhydrides selected from furan-5-carboxylate, 4-{[4-(1,3-dioxoisobenzofuran-5-ylcarbonyloxy)phenyl]cyclohexyl}phenyl 1,3-dioxoisobenzofuran-5-carboxylate, 4,4'-(4,4'-isopropylidene diphenoxy)diphthalic anhydride, 2,2-bis(4-hydroxyphenyl)propanedibenzoate-3,3',4,4'-tetracarboxylic acid dianhydride, and 4,4-(4,4'-isopropylidene diphenoxy)diphthalic anhydride.

12. The method for manufacturing a semiconductor device according to claim 1, characterized in that the interlayer insulating film is made of a polyimide resin containing one or more diamine components selected from p-phenylenediamine, 4,4'-diamino-2,2'-bis(trifluoromethyl)biphenyl, 4,4'-diamino-2,2'-dimethylbiphenyl, diaminodiphenylsulfone, 1,4-bis(4-aminophenoxy)benzene, 1,3-bis(4-aminophenoxy)benzene, 1,3-bis(3-aminophenoxy)benzene, 2-bis[4-(4-aminophenoxy)phenyl]hexafluoropropane, 1,4-bis(3-aminopropyldimethylsilyl)benzene, and 9,9-bis(4-aminophenyl)fluorene.

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