Method for manufacturing semiconductor device having a stone tomb structure, method for manufacturing support sheet, and laminated film for support sheet formation

Abstract

Disclosed is a method for manufacturing a support sheet, which is a method for manufacturing a support sheet used in a manufacturing process of a semiconductor device having a mausoleum structure, the semiconductor device including a substrate, a first chip disposed on the substrate, a plurality of support sheets disposed on the substrate and around the first chip, and a second chip supported by the plurality of support sheets and disposed so as to cover the first chip, the method for manufacturing the support sheet including: (A) a step of preparing a laminated film having, in order, a base material film, a pressure-sensitive adhesive layer, and a support sheet-forming film; (B) a step of forming a plurality of support sheets on a surface of the pressure-sensitive adhesive layer by singulating the support sheet-forming film; and (C) a step of picking up the support sheets from the pressure-sensitive adhesive layer, the support sheet-forming film having a shear viscosity of 4000 Pa·s or more at 120°C.

Description

Technical Field

[0001] This disclosure relates to a method for manufacturing a semiconductor device with a dome-shaped tomb structure. The semiconductor device with the dome-shaped tomb structure includes: a substrate; a first chip disposed on the substrate; a plurality of support sheets disposed on the substrate and surrounding the first chip; and a second chip supported by the plurality of support sheets and disposed to cover the first chip. Furthermore, this disclosure relates to a method for manufacturing the support sheets and a laminated film for forming the support sheets. Additionally, a dome-shaped tomb is a type of stone tomb, comprising a plurality of support stones and plate-shaped rocks placed thereon. In the semiconductor device with the dome-shaped tomb structure, the support sheets are equivalent to the "support stones," and the second chip is equivalent to the "plate-shaped rocks." Background Technology

[0002] In recent years, the field of semiconductor devices has seen a demand for high integration, miniaturization, and high speed. As one type of semiconductor device, the structure of stacking semiconductor chips on a controller chip disposed on a substrate has attracted attention. For example, Patent Document 1 discloses a semiconductor die assembly including a controller die and a memory die supported on the controller die by a support member. Patent Document 1... Figure 1 The semiconductor component 100 shown in Figure A can be described as having a support structure. That is, the semiconductor component 100 includes a packaging substrate 102, a controller chip 103 disposed on the surface of the packaging substrate 102, a memory chip 106a and a memory chip 106b disposed above the controller chip 103, and support members 130a and 130b supporting the memory chip 106a.

[0003] Existing technical documents

[0004] Patent documents

[0005] Patent document: 1 Japanese Patent Publication No. 2017-515306 Summary of the Invention

[0006] The technical problem to be solved by the invention

[0007] Patent Document 1 discloses a support component (support sheet) that can use semiconductor materials such as silicon, and more specifically, can use fragments of semiconductor material obtained by dicing semiconductor wafers (see

[0012] ,

[0014] and

[0015] of Patent Document 1). Figure 2 To manufacture the support sheet for the tomb structure using a semiconductor chip, the process is similar to that of manufacturing a regular semiconductor chip, and includes, for example, the following steps.

[0008] (1) The process of attaching back grind tape to a semiconductor wafer;

[0009] (2) Backside grinding process of semiconductor wafers;

[0010] (3) A process of attaching a film with a pressure-sensitive adhesive layer and an adhesive layer (dicing / die-bonding integrated film) to the dicing ring and the back-grinding semiconductor wafer disposed therein;

[0011] (4) The process of removing the back polishing tape from the semiconductor wafer;

[0012] (5) The process of monolithizing semiconductor wafers;

[0013] (6) The process of picking up a support sheet containing a semiconductor chip and an adhesive sheet from a pressure-sensitive adhesive layer.

[0014] This disclosure provides a method for manufacturing a semiconductor device, which simplifies the process of fabricating a support sheet in the manufacturing process of a semiconductor device with a support structure, thereby enabling stable support of the stacked semiconductor chip. Furthermore, this disclosure provides a method for manufacturing a support sheet and a laminated film for forming the support sheet.

[0015] means for solving technical problems

[0016] One aspect of this disclosure relates to a method for manufacturing a semiconductor device having a tomb structure, the semiconductor device comprising: a substrate; a first chip disposed on the substrate; a plurality of support sheets disposed on the substrate and surrounding the first chip; and a second chip supported by the plurality of support sheets and disposed to cover the first chip. The method for manufacturing the semiconductor device includes the following steps.

[0017] (A) A process for preparing a laminated film having a substrate film, a pressure-sensitive adhesive layer, and a support sheet forming film in sequence;

[0018] (B) A process of forming multiple support sheets on the surface of a pressure-sensitive adhesive layer by monolithizing the support sheet forming film;

[0019] (C) The process of picking up the support sheet from the pressure-sensitive adhesive layer;

[0020] (D) The process of mounting the first chip on a substrate;

[0021] (E) A process of arranging multiple support sheets on a substrate and around the first chip;

[0022] (F) A process for preparing a chip with an adhesive sheet, the chip having an adhesive sheet comprising a second chip and an adhesive sheet disposed on one side of the second chip; and

[0023] (G) The process of constructing a stone tomb structure by placing chips with adhesive sheets on the surface of multiple support sheets.

[0024] According to one aspect of the semiconductor device manufacturing method disclosed herein, a support sheet can be obtained by monolithically forming a support sheet film. Therefore, compared to conventional manufacturing methods that use fragments of semiconductor material obtained by dicing semiconductor wafers as support sheets, the process of manufacturing the support sheet can be simplified. That is, while the processes (1) to (6) mentioned above are conventionally required, since the support sheet forming film does not contain a semiconductor wafer, the processes (1), (2), and (4) related to back-side grinding of the semiconductor wafer can be omitted. Furthermore, since semiconductor wafers, which are more expensive than resin materials, are not used, costs can also be reduced.

[0025] Furthermore, the shear viscosity of the support film at 120°C is 4000 Pa·s or higher. When the shear viscosity of the support film at 120°C is 4000 Pa·s or higher, the degree of flow deformation of the support film is reduced, resulting in stable support of the stacked semiconductor chip. The support film may contain a thermosetting resin layer.

[0026] (A) The pressure-sensitive adhesive layer of the laminated film prepared in step (A) can be either pressure-sensitive or UV-curable. That is, the pressure-sensitive adhesive layer can be cured by UV irradiation or not; in other words, it may or may not contain a photoreactive resin with carbon-carbon double bonds. Furthermore, the pressure-sensitive adhesive layer may also contain a photoreactive resin with carbon-carbon double bonds. For example, the adhesiveness of a designated area of ​​the pressure-sensitive adhesive layer can be reduced by irradiating it with UV light, and for example, a photoreactive resin with carbon-carbon double bonds may remain. In the case of a UV-curable pressure-sensitive adhesive layer, the adhesiveness of the pressure-sensitive adhesive layer can be reduced by performing a step of irradiating the pressure-sensitive adhesive layer with UV light between steps (B) and (C).

[0027] When the support film forming film includes a thermosetting resin layer, the process of heating the support film forming film or the support to cure the thermosetting resin layer or adhesive sheet can be performed at an appropriate time, for example, before process (G). During the stage where the chip with adhesive sheet is arranged in contact with the surfaces of multiple support sheets, the thermosetting resin layer has already cured, thereby preventing the support sheets from deforming as the chip with adhesive sheet is arranged. Furthermore, since the thermosetting resin layer has adhesive properties relative to other components (e.g., the substrate), the adhesive layer can be omitted from the support sheets.

[0028] The thickness of the support film can be, for example, 5 μm to 180 μm or 20 μm to 120 μm. By making the thickness of the support film within this range, a support structure with an appropriate height relative to the first chip (e.g., a controller chip) can be constructed. The support film may contain a thermosetting resin layer. The thermosetting resin layer contains, for example, epoxy resin, and preferably contains an elastomer. By including an elastomer in the thermosetting resin layer constituting the support, stress within the semiconductor device can be mitigated.

[0029] One aspect of this disclosure relates to a method for manufacturing a support sheet, which is a method for manufacturing a support sheet used in the manufacturing process of a semiconductor device having a support structure. The method for manufacturing the support sheet includes the following steps.

[0030] (A) A process for preparing a laminated film having a substrate film, a pressure-sensitive adhesive layer, and a support sheet forming film in sequence;

[0031] (B) A process of forming multiple support sheets on the surface of a pressure-sensitive adhesive layer by monolithizing the support sheet forming film; and

[0032] (C) The process of picking up the support sheet from the pressure-sensitive adhesive layer.

[0033] In addition, the shear viscosity of the film used to form the support sheet is above 4000 Pa·s at 120°C.

[0034] One aspect of this disclosure relates to a laminated film for forming a support sheet, used in a manufacturing process of a semiconductor device having a support-tomb structure, the semiconductor device comprising: a substrate; a first chip disposed on the substrate; a plurality of support sheets disposed on the substrate and surrounding the first chip; and a second chip supported by the plurality of support sheets and disposed to cover the first chip, wherein the laminated film for forming the support sheet sequentially comprises a substrate film, a pressure-sensitive adhesive layer, and the support sheet forming film, and the shear viscosity of the support sheet forming film at 120°C is 4000 Pa·s or higher. The support sheet forming film may contain a thermosetting resin layer.

[0035] Invention Effects

[0036] According to this disclosure, a method for manufacturing a semiconductor device having a support structure is provided, which simplifies the process of fabricating a support sheet and thereby stably supports the stacked semiconductor chips. Furthermore, according to this disclosure, a method for manufacturing a support sheet and a laminated film for forming the support sheet are provided. Attached Figure Description

[0037] Figure 1 This is a cross-sectional view schematically illustrating a first embodiment of a semiconductor device.

[0038] Figure 2 (a), (b) and (c) are plan views that schematically illustrate the positional relationship between the first chip and a plurality of support sheets.

[0039] Figure 3 (a) is a plan view schematically illustrating one embodiment of a laminated film for forming a support sheet. Figure 3 (b) is along Figure 3 (a) is a sectional view cut by the bb line.

[0040] Figure 4 This is a cross-sectional view schematically illustrating the process of bonding a pressure-sensitive adhesive layer to a support sheet to form a film.

[0041] Figure 5 (a), (b), (c), and (d) are schematic cross-sectional views illustrating the fabrication process of the support sheet.

[0042] Figure 6 It is a schematic cross-sectional view showing a substrate with multiple support sheets arranged around the first chip.

[0043] Figure 7 This is a schematic cross-sectional view illustrating an example of a chip with an adhesive sheet.

[0044] Figure 8 It is a schematic cross-sectional view showing the supporting tomb structure formed on the substrate.

[0045] Figure 9 This is a cross-sectional view schematically illustrating a second embodiment of a semiconductor device.

[0046] Figure 10 (a) is a top view showing an example of a substrate with a support sheet used in the embodiment. Figure 10 (b) is along Figure 10 (a) is a sectional view cut by the bb line. Figure 10 (c) is a cross-sectional view showing an example of a stacked body used in the embodiment. Detailed Implementation

[0047] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the accompanying drawings. However, the present invention is not limited to the following embodiments. Furthermore, in this specification, "(meth)acrylic acid" refers to acrylic acid or methacrylic acid, and "(meth)acrylate" refers to acrylate or its corresponding methacrylate. The term "A or B" may include either A or B, or both.

[0048] In this specification, the term "layer," when viewed in a planar view, includes not only the structure forming the entire surface but also the structure forming only a portion of it. Furthermore, the term "process" in this specification refers not only to an independent process but also to any process that achieves its intended function, even if it cannot be clearly distinguished from other processes. The numerical range indicated by "~" represents the range of minimum and maximum values ​​for the values ​​listed before and after the "~".

[0049] In this specification, the content of each component in the composition refers to the total amount of the multiple substances present in the composition when multiple substances equivalent to each component are present in the composition, unless otherwise specified. Furthermore, the exemplary materials may be used alone or in combination of two or more, unless otherwise specified. Also, the upper or lower limit of the numerical ranges described in this specification for a particular period may be replaced with the upper or lower limit of the numerical range for other periods. Furthermore, the upper or lower limit of the numerical ranges described in this specification may be replaced with the values ​​shown in the examples.

[0050] <First Implementation>

[0051] (Semiconductor devices)

[0052] Figure 1 This is a cross-sectional view schematically illustrating a first embodiment of a semiconductor device. Figure 1 The semiconductor device 100 shown includes: a substrate 10, a chip T1 (first chip) disposed on the surface of the substrate 10, a plurality of support sheets Dc disposed on the surface of the substrate 10 and around the chip T1, a chip T2 (second chip) disposed above the chip T1, an adhesive sheet Tc held by the chip T2 and the plurality of support sheets Dc, a chip T3 and a chip T4 stacked on the chip T2, a plurality of wires w electrically connecting electrodes (not shown) on the surface of the substrate 10 to the chips T1 to T4 respectively; and a sealing material 50 filling the gaps between the chips T1 and T2.

[0053] In this embodiment, a support structure is formed on the substrate 10 by multiple support sheets Dc, a chip T2, and an adhesive sheet Tc located between the support sheets Dc and the chip T2. The chip T1 is separated from the adhesive sheet Tc. By appropriately setting the thickness of the support sheets Dc, space can be ensured for the wires w connecting the upper surface of the chip T1 to the substrate 10.

[0054] The substrate 10 can be an organic substrate or a metal substrate such as a lead frame. From the viewpoint of suppressing warping of the semiconductor device 100, the thickness of the substrate 10 is, for example, 90 μm to 300 μm, or 90 μm to 210 μm.

[0055] Chip T1, for example, is a controller chip, bonded to substrate 10 by adhesive sheet Tc and electrically connected to substrate 10 by wire w. When viewed from above, the shape of chip T1 is, for example, rectangular (square or elongated). The length of one side of chip T1 is, for example, less than 5 mm, but can also be 2 mm to 5 mm or 1 mm to 5 mm. The thickness of chip T1 is, for example, 10 μm to 150 μm, but can also be 20 μm to 100 μm.

[0056] Chip T2 is, for example, a memory chip, and is bonded to the support sheet Dc via an adhesive sheet Tc. Viewed from above, chip T2 is larger than chip T1. The shape of chip T2 when viewed from above is, for example, rectangular (square or elongated). The length of one side of chip T2 is, for example, less than 20 mm, but can also be 4 mm to 20 mm or 4 mm to 12 mm. The thickness of chip T2 is, for example, 10 μm to 170 μm, but can also be 20 μm to 120 μm. Additionally, chips T3 and T4 are also, for example, memory chips, bonded to chip T2 via adhesive sheets Tc. The length of one side of chips T3 and T4 only needs to be the same as that of chip T2, and the thickness of chips T3 and T4 also only needs to be the same as that of chip T2.

[0057] The support sheet Dc functions as a spacer forming a space around the chip T1. The support sheet Dc contains a cured product of the support sheet forming film (a cured product of a thermosetting resin composition). As described later, the shear viscosity of the support sheet forming film at 120°C is 4000 Pa·s or higher. Furthermore, as... Figure 2 As shown in (a), two support plates Dc (rectangular shape) can be arranged at spaced positions on both sides of chip T1, or as shown in (a). Figure 2 As shown in (b), a support piece Dc (shape: square, 4 in total) is arranged at the position corresponding to the corner of chip T1, and can also be as follows: Figure 2 As shown in (c), a support sheet Dc (rectangular shape, 4 in total) is disposed at a position corresponding to the edge of chip T1. The length of one side of the support sheet Dc when viewed from above is, for example, less than 20 mm, or 1 mm to 20 mm or 1 mm to 12 mm. The thickness (height) of the support sheet Dc is, for example, 10 μm to 180 μm, or 20 μm to 120 μm.

[0058] (Manufacturing method of support sheet)

[0059] An example of a method for manufacturing the support sheet will be described. The manufacturing method of this embodiment includes the following steps (A) to (C).

[0060] (A) A process for preparing a laminated film 20 for forming a support sheet (hereinafter sometimes referred to as "laminated film 20") having a substrate film 1, a pressure-sensitive adhesive layer 2, and a support sheet forming film D in sequence (see reference). Figure 3 , Figure 4 );

[0061] (B) The process of forming multiple support sheets Da on the surface of the pressure-sensitive adhesive layer 2 by monolithizing the support sheet forming film D (refer to) Figure 5 (b)); and

[0062] (C) The process of picking up the support sheet Da from the pressure-sensitive adhesive layer 2 (refer to) Figure 5 (d)

[0063] in addition, Figure 1 The support sheet Dc shown is the support sheet after its contained adhesive sheet (thermosetting resin composition) has cured. On the other hand, the support sheet Da is the support sheet in the state before its contained adhesive sheet (thermosetting resin composition) has completely cured (for example, see reference). Figure 5 (b)

[0064] Processes (A) to (C) are the processes for manufacturing multiple support sheets Da. The following is a reference... Figures 3-5 The process steps (A) to (C) are explained.

[0065] [(A) Process]

[0066] (A) is the process of preparing the laminated film 20. The laminated film 20 includes a substrate film 1, a pressure-sensitive adhesive layer 2, and a support sheet forming film D. The substrate film 1 is, for example, a polyethylene terephthalate (PET) film. The pressure-sensitive adhesive layer 2 is formed into a circular shape by punching or the like (see reference). Figure 3 (a)). The pressure-sensitive adhesive layer 2 may contain a pressure-sensitive type pressure-sensitive adhesive or a UV-curable type pressure-sensitive adhesive. When the pressure-sensitive adhesive layer 2 contains a UV-curable type pressure-sensitive adhesive, the pressure-sensitive adhesive layer 2 has the property of decreasing adhesiveness upon exposure to UV light. The support sheet forming film D is formed into a circular shape by punching or the like, and has a diameter smaller than that of the pressure-sensitive adhesive layer 2 (see reference). Figure 3 (a)). The film D for forming the support sheet may also include a thermosetting resin layer 5 containing a thermosetting resin composition.

[0067] The thermosetting resin composition constituting the thermosetting resin layer 5 of the support sheet forming film D, after passing through a semi-cured state (stage B), can become a fully cured product (stage C) through a subsequent curing treatment. To facilitate the adjustment of shear viscosity to a specified range, the thermosetting resin composition may contain epoxy resin, curing agent, elastomer (e.g., acrylic resin), and, if necessary, further contain inorganic fillers and curing accelerators. Details of the thermosetting resin composition constituting the thermosetting resin layer 5 of the support sheet forming film D will be described later.

[0068] The thickness of the film D used for forming the support sheet can be, for example, 5 μm to 180 μm or 20 μm to 120 μm. By making the thickness of the film used for forming the support sheet within this range, a support structure with an appropriate height relative to the first chip (e.g., a controller chip) can be constructed.

[0069] The shear viscosity of the support film D at 120°C is 4000 Pa·s or higher. The shear viscosity of the support film D at 120°C can also be 4500 Pa·s or higher, 5000 Pa·s or higher, 7000 Pa·s or higher, 10000 Pa·s or higher, 15000 Pa·s or higher, 18000 Pa·s or higher, 20000 Pa·s or higher, or 23000 Pa·s or higher. When the shear viscosity of the support film D at 120°C is 4000 Pa·s or higher, the degree of flow deformation of the support film is reduced, resulting in improved support stability of the semiconductor chip. There is no particular upper limit to the shear viscosity of the support film D at 120°C; it can be 100000 Pa·s or lower, 70000 Pa·s or lower, or 50000 Pa·s or lower. The shear viscosity of the film D used for forming the support sheet at 120°C can be adjusted, for example, by appropriately adjusting the type and content of the components contained in the thermosetting resin composition described later.

[0070] The laminated film 20 can be manufactured, for example, by laminating a first laminated film and a second laminated film, wherein the first laminated film has a substrate film 1 and a pressure-sensitive adhesive layer 2 on the surface of the substrate film 1, and the second laminated film has a cover film 3 and a support sheet forming film D (see reference) on the surface of the cover film 3. Figure 4 The first laminated film can be obtained through the following steps: forming a pressure-sensitive adhesive layer on the surface of the substrate film 1 by coating, and processing the pressure-sensitive adhesive layer into a predetermined shape (e.g., circular) by punching or the like. The second laminated film can be obtained through the following steps: forming a support sheet forming film on the surface of the cover film 3 (e.g., PET film or polyethylene film) by coating, and processing the support sheet forming film into a predetermined shape (e.g., circular) by punching or the like. When the laminated film 20 is used, the cover film 3 is peeled off at an appropriate time.

[0071] [(B) Process]

[0072] (B) Process (2) involves forming multiple support sheets Da on the surface of the pressure-sensitive adhesive layer 2 by monolithizing the support sheet forming film D. For example... Figure 5 As shown in (a), the cutting ring DR is attached to the laminated film 20. That is, the cutting ring DR is attached to the pressure-sensitive adhesive layer 2 of the laminated film 20, resulting in a state where a support sheet forming film D is disposed inside the cutting ring DR. The support sheet forming film D is monolithically formed by cutting (see reference). Figure 5 (b)). Thus, multiple support sheets Da can be obtained from the support sheet forming film D.

[0073] [(C) Process]

[0074] (C) is the process of picking up the support sheet Da from the pressure-sensitive adhesive layer 2. For example... Figure 5 As shown in (c), the support sheets Da are separated from each other by expanding the substrate film 1. Then, as... Figure 5 As shown in (d), the support sheet Da is peeled off from the pressure-sensitive adhesive layer 2 by pushing the support sheet Da upward with the push clamp 42, and the support sheet Da is picked up by suction with the suction chuck 44.

[0075] (Semiconductor device manufacturing method)

[0076] The manufacturing method of the semiconductor device 100 will be described. The manufacturing method of this embodiment includes steps (A) to (C), and also includes steps (D) to (H) below.

[0077] (D) The process of arranging the first chip T1 on the substrate 10;

[0078] (E) A process of arranging a plurality of support sheets Da (at least a support sheet Da comprising a metal sheet 6p) obtained by the manufacturing method on the substrate 10 and around the first chip T1 (refer to) Figure 6 );

[0079] (F) The process of preparing a chip T2a with an adhesive sheet, wherein the chip T2a with an adhesive sheet includes a second chip T2 and an adhesive sheet Ta disposed on one side of the second chip T2 (see reference). Figure 7 );

[0080] (G) The process of constructing a stone-supported tomb structure by placing chips T2a with adhesive sheets on the surfaces of multiple support sheets Dc (refer to) Figure 8 );

[0081] (H) The process of sealing the gap between chip T1 and chip T2 with sealing material 50, etc. (refer to) Figure 1 ).

[0082] Processes (D) to (H) are processes for constructing a support structure on substrate 10 using multiple support sheets Da. The following refers to... Figures 6-8 The processes (D) to (H) are described.

[0083] [(D) Process]

[0084] (D) is a process of placing the first chip T1 on the substrate 10. For example, firstly, the chip T1 is placed at a predetermined position on the substrate 10 via an adhesive layer T1c. Then, the chip T1 is electrically connected to the substrate 10 via a wire w.

[0085] [(E) Process]

[0086] (E) is a process in which multiple support sheets Da are arranged on the substrate 10 and around the first chip T1. The chip is fabricated through this process. Figure 6 The structure 30 shown includes a substrate 10, a chip T1 disposed on the surface of the substrate 10, and a plurality of support sheets Da. The support sheets Da are disposed by a pressing process. The pressing process is preferably performed for 0.5 seconds to 3.0 seconds at a temperature of 80°C to 180°C and a pressure of 0.01 MPa to 0.50 MPa. Regarding the support sheets Da, the adhesive sheet 5p contained therein may be completely cured at the time of step (E) to become the support sheet Dc, or it may not be completely cured at that time. Preferably, the adhesive sheet 5p contained in the support sheet Da is completely cured before the start of step (G) to become the adhesive sheet 5c.

[0087] [(F) Process]

[0088] (F) Process is preparation Figure 7 The process of the chip T2a with adhesive sheet shown is illustrated. The chip T2a with adhesive sheet includes a chip T2 and an adhesive sheet Ta disposed on one surface of the chip T2. The chip T2a with adhesive sheet can be obtained, for example, using a semiconductor wafer and a die-bonded integrated film, through a dicing process and a pick-and-place process.

[0089] [(G) process]

[0090] (G) is a process in which a chip T2a with an adhesive sheet is placed above a chip T1 in contact with the upper surfaces of multiple support sheets Dc. Specifically, the chip T2a is pressed onto the upper surface of the support sheets Dc via the adhesive sheet Ta. This pressing process is preferably performed for 0.5 to 3.0 seconds at 80°C to 180°C and 0.01 MPa to 0.50 MPa. Subsequently, the adhesive sheet Ta is cured by heating. This curing process is preferably performed for 5 minutes or more at 60°C to 175°C and 0.01 MPa to 1.0 MPa. Thus, the adhesive sheet Ta is cured to become the adhesive sheet Tc. After this process, a support structure is constructed on the substrate 10 (see reference). Figure 8 ).

[0091] After process (G) and before process (H), chip T3 is disposed on chip T2 using an adhesive sheet, and then chip T4 is disposed on chip T3 using an adhesive sheet. The adhesive sheet can be any thermosetting resin composition similar to the adhesive sheet Ta described above, and is cured by heating to become adhesive sheet Tc (see reference). Figure 1 On the other hand, chips T2, T3, and T4 are electrically connected to the substrate 10 via wires w, respectively. Furthermore, the number of chips stacked on top of chip T1 is not limited to three as in this embodiment; it can be appropriately set.

[0092] [(H) process]

[0093] Process (H) involves sealing the gap between chip T1 and chip T2 using sealing material 50. After this process, the process is complete. Figure 1 The semiconductor device 100 shown.

[0094] (Thermosetting resin composition)

[0095] As described above, in order to easily adjust the shear viscosity to a specified range, the thermosetting resin composition constituting the thermosetting resin layer 5 for forming the support sheet film D contains epoxy resin, curing agent, and elastomer, and may further contain inorganic fillers and curing accelerators as needed. According to the research of the inventors, the support sheet Da and the cured support sheet Dc preferably have the following characteristics.

[0096] • Feature 1: When the support sheet Da is hot-pressed to a specified position on the substrate 10, it is not easy for positional displacement to occur;

[0097] Feature 2: The adhesive sheet 5c in the semiconductor device 100 provides stress relief (the thermosetting resin composition contains an elastomer (rubber component));

[0098] • Feature 3: The adhesive strength of the adhesive sheet Tc to the chip with adhesive sheet is sufficiently high (the grain shear strength of the adhesive sheet 5c (i.e., the cured film containing the thermosetting resin layer) relative to the adhesive sheet Tc is, for example, 2.0 MPa to 7.0 MPa or 3.0 MPa to 6.0 MPa).

[0099] Characteristic 4: The shrinkage rate during curing is sufficiently small;

[0100] Feature 5: Good visibility of the camera-based support sheet Da during the pickup process (thermosetting resin composition, for example, containing colorants);

[0101] Feature 6: Adhesive sheet 5c has sufficient mechanical strength.

[0102] [Epoxy Resin]

[0103] There are no particular limitations on epoxy resins if they are substances that provide adhesive properties for curing. The following can be used: difunctional epoxy resins such as bisphenol A, bisphenol F, and bisphenol S; phenolic varnish epoxy resins such as phenolic varnish epoxy resins and cresol varnish epoxy resins. Furthermore, commonly known resins such as polyfunctional epoxy resins, glycidylamine epoxy resins, heterocyclic epoxy resins, and alicyclic epoxy resins can also be used. These can be used individually or in combination.

[0104] [Curing agent]

[0105] Examples of curing agents include phenolic resins, ester compounds, aromatic amines, aliphatic amines, and acid anhydrides. Among these, phenolic resins are preferred from the viewpoint of achieving high grain shear strength. Commercially available phenolic resins include, for example: LF-4871 (trade name, BPA phenolic varnish type phenolic resin) manufactured by DIC Corporation; HE-100C-30 (trade name, phenyl aralkyl type phenolic resin) manufactured by AIR WATER INC.; Phenolite KA and TD series manufactured by DIC Corporation; Milex XLC- and XL series (e.g., Milex XLC-LL) manufactured by Mitsui Chemicals, Inc.; HE series (e.g., HE100C-30) manufactured by AIR WATER INC.; MEHC-7800 series (e.g., MEHC-7800-4S) manufactured by Meiwa Plastic Industries, Ltd.; JDPP series manufactured by JEF Chemical Corporation; and PSM series (e.g., PSM-4326) manufactured by Gun Ei Chemical Industry Co., Ltd. These can be used individually or in combination.

[0106] Regarding the mixing ratio of epoxy resin and phenolic resin, from the viewpoint of achieving high grain shear strength, the equivalent ratio of epoxy resin to hydroxyl resin is preferably 0.6 to 1.5, more preferably 0.7 to 1.4, and even more preferably 0.8 to 1.3. By keeping the mixing ratio within the above range, it is easy to achieve sufficiently high levels of both curability and flowability.

[0107] [Elastomer]

[0108] Examples of elastomers include: acrylic resins, polyester resins, polyamide resins, polyimide resins, silicone resins, polybutadiene, acrylonitrile, epoxy-modified polybutadiene, maleic anhydride-modified polybutadiene, phenol-modified polybutadiene, and carboxyl-modified acrylonitrile.

[0109] From the viewpoint of membrane formability, acrylic resins are preferred as elastomers, and even more preferred are acrylic resins such as epoxy-containing (meth)acrylic copolymers obtained by polymerizing functional monomers such as glycidyl acrylate or glycidyl methacrylate, which have epoxy or glycidyl groups as crosslinking functional groups. Among acrylic resins, epoxy-containing (meth)acrylic ester copolymers and epoxy-containing acrylic rubbers are preferred, and epoxy-containing acrylic rubbers are more preferred. Epoxy-containing acrylic rubbers are rubbers with epoxy groups, mainly composed of acrylates, including copolymers of butyl acrylate and acrylonitrile, copolymers of ethyl acrylate and acrylonitrile, etc. Furthermore, acrylic resins may not only have epoxy groups, but also crosslinking functional groups such as alcoholic or phenolic hydroxyl groups and carboxyl groups.

[0110] Commercially available acrylic resins include: SG-70L, SG-708-6, WS-023EK30, SG-280EK23, and SG-P3 solvent-modified products (trade name: acrylic rubber, weight average molecular weight: 800,000, Tg: 12℃, solvent: cyclohexanone) manufactured by Nagase ChemteX Corporation, and SG-P3 low molecular weight products (trade name: acrylic rubber manufactured by Nagase ChemteX Corporation, weight average molecular weight: 300,000, Tg: 12℃, solvent: cyclohexanone), etc.

[0111] From the viewpoint of membrane formability, the glass transition temperature (Tg) of the acrylic resin is preferably -50°C to 50°C, more preferably -30°C to 30°C. From the viewpoint of membrane formability, the weight-average molecular weight (Mw) of the acrylic resin is preferably 100,000 to 3,000,000, more preferably 500,000 to 2,000,000. Here, Mw refers to the value obtained by gel permeation chromatography (GPC) and conversion using a standard curve based on standard polystyrene. Furthermore, by using an acrylic resin with a narrow molecular weight distribution, there is a tendency to form highly elastic adhesive sheets.

[0112] From the viewpoint of achieving high grain shear strength (shear strength), the amount of acrylic resin contained in the thermosetting resin composition is preferably 10 to 200 parts by mass relative to 100 parts by mass of the total epoxy resin and epoxy resin curing agent, more preferably 20 to 100 parts by mass.

[0113] From the viewpoint of achieving high shear viscosity, the amount of acrylic resin contained in the thermosetting resin composition is preferably 50 parts by mass or more, relative to 100 parts by mass of the total epoxy resin and epoxy resin curing agent.

[0114] [Inorganic packing]

[0115] Examples of inorganic fillers include: aluminum hydroxide, magnesium hydroxide, calcium carbonate, magnesium carbonate, calcium silicate, magnesium silicate, calcium oxide, magnesium oxide, aluminum oxide, aluminum nitride, aluminum borate whiskers, boron nitride, crystalline silicon dioxide, and amorphous silicon dioxide. These can be used individually or in combination with two or more.

[0116] From the viewpoint of achieving high grain shear strength, the average particle size of the inorganic filler is preferably 0.005 μm to 1.0 μm, more preferably 0.05 μm to 0.5 μm. From the viewpoint of achieving high grain shear strength, the surface of the inorganic filler is preferably chemically modified. Examples of materials for chemically modifying the surface include silane coupling agents. Examples of functional groups that can be used in silane coupling agents include vinyl, acryloyl, epoxy, mercapto, amino, diamino, alkoxy, and ethoxy groups.

[0117] From the viewpoint of achieving high grain shear strength (shear strength), the content of inorganic filler is preferably 20 to 200 parts by mass relative to 100 parts by mass of the resin component of the thermosetting resin composition, and more preferably 30 to 100 parts by mass.

[0118] [Curing Accelerator]

[0119] Examples of curing accelerators include imidazoles and their derivatives, organophosphorus compounds, secondary amines, tertiary amines, and quaternary ammonium salts. From the viewpoint of achieving high grain shear strength, imidazole compounds are preferred. Examples of imidazoles include 2-methylimidazolium, 1-benzyl-2-methylimidazolium, 1-cyanoethyl-2-phenylimidazolium, and 1-cyanoethyl-2-methylimidazolium. These can be used individually or in combination.

[0120] From the viewpoint of achieving high grain shear strength (shear strength), the content of curing accelerator in the thermosetting resin composition is preferably 0.04 parts by mass to 3 parts by mass, more preferably 0.04 parts by mass to 0.2 parts by mass, relative to a total of 100 parts by mass of epoxy resin and epoxy resin curing agent.

[0121] <Second Implementation>

[0122] Figure 9This is a schematic cross-sectional view illustrating a second embodiment of the semiconductor device. In contrast to the semiconductor device 100 of the first embodiment, where the chip T1 and the adhesive sheet Tc are separate, in the semiconductor device 200 of this embodiment, the chip T1 and the adhesive sheet Tc are in contact. That is, the adhesive sheet Tc is in contact with the upper surface of the chip T1 and the upper surface of the support sheet Dc. For example, by appropriately setting the thickness of the film D for forming the support sheet, the position of the upper surface of the chip T1 can be made to coincide with the position of the upper surface of the support sheet Dc.

[0123] In the semiconductor device 200, chip T1 is not wire-bonded to substrate 10, but rather connected via flip chip. Furthermore, if the chip is configured to be embedded in the adhesive sheet Ta of chip T2a, which together with chip T2 forms an adhesive sheet, then even if chip T1 is wire-bonded to substrate 10, chip T1 can still be in contact with adhesive sheet Tc.

[0124] Example

[0125] The present disclosure will be described below through embodiments, but the present invention is not limited to these embodiments.

[0126] [Fabrication of the membrane for forming the support sheet]

[0127] <Preparation of Varnish>

[0128] Use the materials shown in Table 1 according to the composition ratios (unit: parts by mass) shown in Table 1. Add cyclohexanone to the epoxy resin, phenolic resin, and inorganic filler, and stir to mix. Adjust the content of cyclohexanone in the final varnish to a solid component ratio of 40% by mass. Add the elastomer, then add the coupling agent and curing accelerator, and stir until all components are homogeneous to prepare varnishes A to E.

[0129] Details of each component shown in Table 1 are as follows.

[0130] • Epoxy resin: YDCN-700-10 (trade name, manufactured by NIPPON STEEL & SUMIKIN CHEMICAL CO.,LTD., o-cresyl phenolic varnish type epoxy resin, epoxy equivalent: 209g / eq)

[0131] • EXA-830CRP (trade name, manufactured by DIC Corporation, bisphenol F type epoxy resin, epoxy equivalent: 159g / eq)

[0132] • Phenolic resin (curing agent): HE-100C-30 (trade name, manufactured by AIR WATER INC., phenolic aralkyl type phenolic resin, hydroxyl equivalent: 170g / eq)

[0133] • Phenolic resin (curing agent): PSM-4326 (trade name, manufactured by Gun Ei Chemical Industry Co., Ltd., phenolic resin for varnish, hydroxyl equivalent: 105g / eq)

[0134] • Inorganic filler: Aerosil R972 (trade name, manufactured by NIPPON AEROSIL CO.,LTD., silica, average particle size 0.016μm)

[0135] • Inorganic filler: SC2050-HLG (trade name, manufactured by Admatechs Company Limited, silica filler dispersion, average particle size 0.50μm)

[0136] • Elastomer: SG-P3 solvent-modified product (trade name, manufactured by Nagase ChemteX Corporation, acrylic rubber, weight-average molecular weight: 800,000, Tg: 12℃, solvent: cyclohexanone)

[0137] • Elastomer: SG-P3 low molecular weight product (trade name, manufactured by Nagase ChemteX Corporation, acrylic rubber, weight average molecular weight: 300,000, Tg: 12℃, solvent: cyclohexanone)

[0138] • Coupling agent: A-189 (trade name, manufactured by Momentive Performance Materials Inc., γ-mercaptopropyltrimethoxysilane)

[0139] • Coupling agent: A-1160 (trade name, manufactured by Momentive Performance Materials Inc., γ-ureidopropyltriethoxysilane)

[0140] • Curing accelerator: Curezol 2PZ-CN (trade name, manufactured by SHIKOKU CHEMICALS CORPORATION, 1-cyanoethyl-2-phenylimidazolium)

[0141] [Table 1]

[0142]

[0143] <Fabrication of the film for forming the support sheet>

[0144] (Example 1)

[0145] Varnish A was filtered using a 100-mesh filter and then degassed under vacuum. A 38 μm thick polyethylene terephthalate (PET) film with a release treatment was prepared as the substrate film, and the degassed varnish A was coated onto the PET film. The coated varnish A was then subjected to two-stage heating and drying at 90°C for 5 minutes, followed by 130°C for 5 minutes, to obtain the support sheet forming film of Example 1 in stage B. The coating thickness of varnish A was adjusted to 50 μm.

[0146] (Example 2)

[0147] The varnish A was replaced with varnish B, and the support sheet forming film of Example 2 was obtained in the same manner as in Example 1.

[0148] (Example 3)

[0149] The varnish A was replaced with varnish C, and the support sheet forming film of Example 3 was obtained in the same manner as in Example 1.

[0150] (Comparative Example 1)

[0151] The varnish A was replaced with varnish D, and the film for forming the support sheet of Comparative Example 1 was obtained in the same manner as in Example 1.

[0152] (Comparative Example 2)

[0153] The varnish A was replaced with varnish E, and the film for forming the support sheet of Comparative Example 2 was obtained in the same manner as in Example 1.

[0154] [Evaluation of the film used for support sheet formation]

[0155] <Determination of Shear Viscosity>

[0156] The films used for forming the support sheets in Examples 1-3, Comparative Examples 1 and 2 (50 μm thick) were each cut to a specified size, and four films were prepared. The four films were then laminated on a heating plate at 60°C using a rubber roller, thereby producing a sample with a thickness of 200 μm. The samples obtained by punching were tested using a shear viscometer (manufactured by TA Instruments Japan Inc., trade name: ARES-G2) at a measurement temperature of 120°C under the following conditions. The results are shown in Table 1.

[0157] • Measurement frequency: 1Hz

[0158] • Heating rate: 5℃ / min

[0159] • Measurement temperature: 35℃~130℃

[0160] • Axial force: 100gf (0.98N)

[0161] <Evaluation of Support Stability>

[0162] (Fabrication of a substrate with a support sheet)

[0163] The support sheet forming films (50 μm thick) from Examples 1 to 3 and Comparative Examples 1 and 2 were respectively attached to pressure-sensitive adhesive films (10 μm thick, manufactured by Showa Denko Materials Co., Ltd.) having a substrate film and a pressure-sensitive adhesive layer to create laminated films. The obtained laminated films were monolithized using a fully automatic cutting machine DFD-6361 (manufactured by DISCO Inc.). Cutting blades ZH05-SD4000-N1-xx-BB (all manufactured by DISCO Inc.) were used. The cutting conditions were a blade rotation speed of 4000 rpm, a cutting speed of 50 mm / s, and a size of 6 mm × 3 mm. Next, the support sheets were picked up using a pick-up jig.

[0164] Next, the two support plates were placed on a solder resist substrate (TAIYO HOLDINGS CO.,LTD., trade name: AUS-308) and hot-pressed together to obtain the substrates with support plates of Examples 1 to 3, and Comparative Examples 1 and 2. The hot-pressing conditions were: temperature 120°C, time 1 second, and pressure 0.1 MPa. Figure 10 (a) is a top view showing an example of a substrate with a support sheet used in the embodiment. Figure 10 (b) is along Figure 10 The sectional view at line bb in (a). Figure 10 As shown, the substrate 300 with support sheets includes: a substrate 310 and two support sheets Da disposed on the substrate 310 in such a way as to be connected to the two opposing sides of the substrate 310.

[0165] (Fabrication of a chip with an adhesive layer)

[0166] A die-bonding integrated adhesive film (film adhesive: 50 μm thick, pressure-sensitive adhesive film: 110 μm thick, manufactured by Showa Denko Materials Co., Ltd.) containing both a film adhesive and a pressure-sensitive adhesive film, and a silicon wafer with a thickness of 400 μm were prepared. A die-bonding sample was fabricated by laminating the silicon wafer onto the film adhesive of the die-bonding integrated adhesive film at a stage temperature of 70°C.

[0167] The diced samples were cut using a fully automated DFD-6361 dicing machine (manufactured by DISCO CORPORATION). The cutting was performed using a stepped cutting method with two blades: ZH05-SD3500-N1-xx-DD and ZH05-SD4000-N1-xx-BB (both manufactured by DISCO CORPORATION). The cutting conditions were: blade speed 4000 rpm, cutting speed 50 mm / s, and chip size 6 mm × 12 mm. The first stage of cutting left approximately 200 μm of silicon wafer residue. The second stage of cutting then created a 20 μm kerf in the pressure-sensitive adhesive film. Finally, a pick-up chuck was used to pick up the chip, resulting in a chip with an adhesive pad attached.

[0168] (Evaluation sample preparation)

[0169] The adhesive sheets of the chips with adhesive sheets were respectively disposed on the support sheets of the substrates with support sheets in Examples 1 to 3 and Comparative Examples 1 and 2, and then hot-pressed together. The hot-pressing conditions were: temperature 120°C, time 1 second, and pressure 0.1 MPa. Figure 10 (c) is a cross-sectional view showing an example of a stacked body used in the embodiment. Figure 10 As shown in (c), the laminate 400 includes: a substrate 300 with a support sheet, a chip T300a with an adhesive sheet including an adhesive sheet Ta and a chip T300, and two support sheets Da disposed between the substrate 300 with the support sheet and the chip T300a with the adhesive sheet. Next, the laminate obtained by hot pressing is placed in a dryer and heated and cured at 170°C for 1 hour, thereby obtaining the evaluation samples of Examples 1 to 3 and Comparative Examples 1 and 2.

[0170] (Observation through a cross-section under a microscope)

[0171] The cross-sections of the evaluation samples from Examples 1 to 3, and Comparative Examples 1 and 2 were observed under a microscope to evaluate the deviation in the height of the support sheet. Those where the support sheet did not deform or shrink, and the substrate and chip remained parallel, were rated "A"; those where the support sheet deformed or shrank, and the substrate and chip became non-parallel, were rated "B". The results are shown in Table 2.

[0172] [Table 2]

[0173]

[0174] As shown in Table 2, compared with the evaluation samples of Comparative Examples 1 and 2, which used a support sheet forming film with a shear viscosity of 4000 Pa·s or higher at 120°C, the deviation in the height of the support sheet was suppressed in the evaluation samples of Examples 1 to 3, which used a support sheet forming film with a shear viscosity of less than 4000 Pa·s at 120°C. It is thus confirmed that the semiconductor device manufacturing method of the present invention can manufacture a semiconductor device capable of stably supporting stacked semiconductor chips.

[0175] Industrial availability

[0176] According to this disclosure, a method for manufacturing a semiconductor device having a support structure is provided, which simplifies the process of fabricating a support sheet and thereby stably supports the stacked semiconductor chips. Furthermore, according to this disclosure, a method for manufacturing a support sheet and a laminated film for forming the support sheet are provided.

[0177] Symbol Explanation

[0178] 1-Substrate film, 2-Pressure-sensitive adhesive layer, 5-Thermosetting resin layer, 10, 310-Substrate, 20-Laminated film for forming support sheet, 50-Sealing material, 100, 200-Semiconductor device, 300-Substrate with support sheet, 400-Laminated body, D-Film for forming support sheet, Da-Support sheet, Dc-Support sheet (cured), T1-First chip, T2-Second chip, T300: Chip, T2a, T300a-Chip with adhesive sheet, Ta-Adhesive sheet, Tc-Adhesive sheet (cured).

Claims

1. A method for manufacturing a semiconductor device, which is a method for manufacturing a semiconductor device having a dolmen structure, the semiconductor device comprising: Substrate; a first chip disposed on the substrate; a plurality of support pieces disposed on the substrate and around the first chip; and a second chip supported by the plurality of support pieces and disposed so as to cover the first chip, the method for manufacturing the semiconductor device comprising: (A) a step of preparing a laminated film provided with, in order, a base material film, a pressure-sensitive adhesive layer, and a support piece-forming film; (B) a step of forming a plurality of support pieces on a surface of the pressure-sensitive adhesive layer by singulating the support piece-forming film; (C) a step of picking up the support pieces from the pressure-sensitive adhesive layer; (D) a step of disposing a first chip on a substrate; (E) a step of disposing a plurality of the support pieces on the substrate and around the first chip; (F) a step of preparing a chip with an adhesive sheet provided with a second chip and an adhesive sheet provided on one face of the second chip; and (G) a step of constructing a dolmen structure by disposing the chip with the adhesive sheet on surfaces of the plurality of support pieces, the support piece-forming film has a shear viscosity of 15000 Pa·s or more at 120°C, the support piece-forming film includes a thermosetting resin layer composed of a thermosetting resin composition, the thermosetting resin composition contains an epoxy resin, a curing agent, and an elastomer, and the elastomer includes an epoxy group-containing acrylic rubber.

2. The method for manufacturing the semiconductor device according to claim 1, wherein the method for manufacturing the semiconductor device includes a step of heating the support piece-forming film or the support pieces before the step (G).

3. A method of manufacturing a support sheet, which is a method of manufacturing a support sheet used in a manufacturing process of a semiconductor device having a mausoleum structure, the semiconductor device comprising: Substrate; a first chip disposed on the substrate; a plurality of support pieces disposed on the substrate and around the first chip; and a second chip supported by the plurality of support pieces and disposed so as to cover the first chip, the method for manufacturing the semiconductor device comprising: (A) a step of preparing a laminated film provided with, in order, a base material film, a pressure-sensitive adhesive layer, and a support piece-forming film; (B) a step of forming a plurality of support pieces on a surface of the pressure-sensitive adhesive layer by singulating the support piece-forming film; and (C) a step of picking up the support pieces from the pressure-sensitive adhesive layer, the support piece-forming film has a shear viscosity of 15000 Pa·s or more at 120°C, the support piece-forming film includes a thermosetting resin layer composed of a thermosetting resin composition, the thermosetting resin composition contains an epoxy resin, a curing agent, and an elastomer, and the elastomer includes an epoxy group-containing acrylic rubber.

4. A laminated film for support sheet formation, which is used in a manufacturing process of a semiconductor device having a stele tomb structure, the semiconductor device comprising: Substrate; a first chip disposed on the substrate; a plurality of support pieces disposed on the substrate and around the first chip; and a second chip supported by the plurality of support pieces and disposed so as to cover the first chip, the support piece-forming laminated film being provided with, in order: a base material film; a pressure-sensitive adhesive layer; and a support piece-forming film, the support piece-forming film has a shear viscosity of 15000 Pa·s or more at 120°C, the support piece-forming film includes a thermosetting resin layer composed of a thermosetting resin composition, the thermosetting resin composition contains an epoxy resin, a curing agent, and an elastomer, and the elastomer includes an epoxy group-containing acrylic rubber. The thermosetting resin composition contains an epoxy resin, a curing agent, and an elastomer, the elastomer including an epoxy group-containing acrylic rubber.

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