Method for manufacturing semiconductor device

Abstract

A method for manufacturing a semiconductor device according to one example involves: positioning semiconductor chip components 20A, 20Bin a flip chip bonder so that electrodes 25 of the semiconductor chip components 20A, 20B face electrodes 15 of an interposer substrate 10; and heating the semiconductor chip components 20A, 20B at a low temperature to temporarily crimp the semiconductor chip components 20A, 20B to the interposer substrate 10. An underfill material 30 is filled between the temporarily crimped semiconductor chip components 20A, 20B and the interposer substrate 10, and a temporarily connected body 100B is manufactured. Thereafter, the temporarily connected body 100B is heated at a high temperature by means of a reflow device 300. The temporary crimping temperature is lower than the reflow temperature and is 180°C or less. Consequently, warping of the semiconductor chip components when the semiconductor chip components are bonded by thermal compression bonding (TCB) is reduced and connection reliability is improved.

Description

Method for manufacturing a semiconductor device

[0001] The present disclosure relates to a method for manufacturing a semiconductor device.

[0002] In recent years, with the rapid increase in functionality of electronic devices represented by AI / HPC, etc., the size and density of semiconductor packages have been rapidly increasing. The package structure is not limited to the high density of surface mounting, but also includes inorganic (silicon) or organic interposer (Bridge die / RDL) technology, 2.xD mounting using the same, and 3D mounting (HBM / Chiplet) technology using TSV, etc., and the package structure and mounting process are becoming more complex and diverse. For example, Resonac Co., Ltd. is mainly based on the 'Packaging Solution Center' and is developing technologies for next-generation semiconductor packaging processes from the perspective of customers (semiconductor manufacturers) by combining mounting processes and materials.

[0003] As a technology in such a semiconductor package field, Patent Document 1 (see paragraphs

[0058] to

[0062] ) discloses a method of mounting a semiconductor chip on a semiconductor substrate and filling an underfill material between the semiconductor substrate and the semiconductor chip.

[0004] Japanese Unexamined Patent Application Publication No. 2015-067788

[0005] When semiconductor chip components are mounted on a semiconductor substrate under normal thermal compression bonding (TCB) conditions, warping may occur in the semiconductor chip components. This is thought to be partly due to the fact that under normal TCB conditions, the heating temperature is high (e.g., 260°C or higher), which can cause temperature unevenness in the heater, leading to the formation of residual stress in the semiconductor chip components. When such warping occurs, the distance between the electrodes varies in the planar direction when mounting the semiconductor chip components on the semiconductor substrate and connecting the two electrodes, thus reducing the reliability of the connection between them. For example, the distance between the semiconductor chip component and the semiconductor substrate may differ on the inside and outside in the planar direction due to the warping, with the distance between the outer electrodes of the semiconductor chip component being greater than the distance between the inner electrodes. Therefore, it is desirable to reduce the warping of semiconductor chip components when mounting them on a semiconductor substrate and to improve the reliability of the connection of semiconductor devices.

[0006] The purpose of this disclosure is to provide a method for manufacturing a semiconductor device that can improve connection reliability.

[0007] [1] This disclosure relates in part to a method for manufacturing a semiconductor device. This method for manufacturing a semiconductor device comprises the steps of: preparing a semiconductor substrate having a substrate body and a plurality of first electrodes, and at least one semiconductor chip component having a plurality of second electrodes; positioning the semiconductor chip component on the semiconductor substrate such that the plurality of second electrodes face the plurality of first electrodes, and heating the semiconductor chip component at a first temperature to temporarily press-bond the semiconductor chip component to the semiconductor substrate; filling the space between the temporarily pressed semiconductor chip component and the semiconductor substrate with underfill material to create a temporary connector; and heating the temporary connector at a second temperature. In this manufacturing method, the first temperature is lower than the second temperature, and is 180°C or lower.

[0008] In this manufacturing method, the first temperature during temporary crimping is lower than the second temperature, being 180°C or below. In this case, the temperature at which the semiconductor chip components are initially crimped (temporarily crimped) is lower than in conventional methods, and the heating during temporary crimping makes it less likely for the semiconductor chip components to warp. On the other hand, in a later process, the temporary connector filled with underfill material is heated at a second temperature higher than the first temperature, causing the underfill material to harden and the second electrode of the semiconductor chip component to permanently bond to the first electrode of the semiconductor substrate. As a result, semiconductor devices with reduced warping and improved connection reliability can be manufactured.

[0009] [2] In the semiconductor device manufacturing method described in [1] above, the first temperature is preferably 150°C or lower. In this case, the warping of the semiconductor chip component is further reduced. Therefore, the connection reliability of the semiconductor device is further improved.

[0010] [3] In the semiconductor device manufacturing method described in [1] or [2] above, the second temperature may be 200°C or higher. In this case, when the semiconductor chip component is permanently connected to the semiconductor substrate, the second electrode is reliably connected to the first electrode by melting at high temperature. Therefore, the connection reliability of the semiconductor device is further enhanced.

[0011] [4] In any of the semiconductor device manufacturing methods described in [1] to [3] above, the step of heating the temporary connector at the second temperature is preferably performed while applying pressure to the temporary connector at a pressure of 0.05 MPa to 1 MPa. In this case, the semiconductor chip component is firmly connected to the semiconductor substrate, and the second electrode is reliably connected to the first electrode. Therefore, the connection reliability of the semiconductor device is further enhanced.

[0012] [5] In any of the semiconductor device manufacturing methods described in [1] to [4] above, it is preferable that the temporary connector be heated in a vacuum inside the heating device housing the temporary connector. In this case, air or moisture contained in the connection between the first electrode and the second electrode or in the voids of the underfill material is reliably removed by vacuum. As a result, impurities are reduced, and the connection reliability of the semiconductor device is further improved.

[0013] [6] Any of the semiconductor device manufacturing methods described in [1] to [5] above may further include a step of sealing semiconductor chip components after filling with underfill material. In this case, the semiconductor chip components are sealed and protected by the sealing material.

[0014] [7] In the semiconductor device manufacturing method described in [6] above, it is preferable to heat the temporary connector at a second temperature before sealing the semiconductor chip component. In this case, the temporary connector is heated reliably and uniformly, and the second electrode is reliably connected to the first electrode. Therefore, the connection reliability of the semiconductor device is further enhanced.

[0015] [8] In any of the semiconductor device manufacturing methods described in [1] to [5] above, the underfill material may be filled when the semiconductor chip components are sealed. In this case, the injection of the underfill material to protect the electrode connections and the formation of the sealing layer to protect the semiconductor chip components are performed almost simultaneously. This improves the manufacturing efficiency of the semiconductor device.

[0016] [9] In any of the semiconductor device manufacturing methods described in [1] to [8] above, in the temporary crimping step, multiple second electrodes may be temporarily connected to multiple first electrodes, and in the step of heating the temporary connection at a second temperature, multiple second electrodes may be permanently connected to multiple first electrodes. In this case, since the electrodes are temporarily connected by temporary crimping, the semiconductor chip components will not be misaligned when the underfill material is filled. Furthermore, since the temporary connection is heated at a high second temperature in a later step, the electrodes can be firmly connected to each other. Here, "temporary connection of electrodes" means that the electrodes are in contact (touching), and "permanent connection of electrodes" means that the electrodes are wet (solder forms an alloy layer).

[0017]

[10] In any of the semiconductor device manufacturing methods described in [1] to [9] above, the underfill material is preferably a thermosetting resin composition containing a thermosetting component. In the step of heating the temporary connector at the second temperature, it is preferable that the underfill material is thermosetting. In this case, when the temporary connector is heated at the second temperature, not only is the connection between the electrodes strengthened, but the underfill material is also hardened. Thus, manufacturing efficiency is improved.

[0018]

[11] In any of the semiconductor device manufacturing methods described in [1] to

[10] above, it is preferable that the plurality of first electrodes and the plurality of second electrodes are flux-free. In this case, it is possible to prevent flux from remaining.

[0019] According to this disclosure, the connectivity reliability of semiconductor devices can be improved.

[0020] Figures 1(a) to 1(c) are cross-sectional views illustrating a method for manufacturing a semiconductor device according to the first embodiment. Figure 2 is a cross-sectional view illustrating a method for manufacturing a semiconductor device according to the first embodiment, and is a cross-sectional view illustrating a reflow process performed after the process shown in Figure 1(c). Figures 3(a) to 3(c) are cross-sectional views illustrating a method for manufacturing a semiconductor device according to the first embodiment, and are cross-sectional views illustrating each process performed after the reflow process shown in Figure 2. Figures 4(a) and 4(b) are cross-sectional views illustrating a method for manufacturing a semiconductor device according to the first embodiment, and are cross-sectional views illustrating each process performed after the process shown in Figure 3(c). Figures 5(a) to 5(c) are cross-sectional views illustrating a method for manufacturing a semiconductor device according to the second embodiment. Figure 6 is a cross-sectional view illustrating a method for manufacturing a semiconductor device according to the second embodiment, and is a cross-sectional view illustrating a reflow process performed after the process shown in Figure 5(c). Figures 7(a) to 7(c) are cross-sectional views illustrating a method for manufacturing a semiconductor device according to the second embodiment, and are cross-sectional views illustrating each process performed after the reflow process shown in Figure 6.

[0021] The embodiments of this disclosure will be described in detail below with reference to the drawings. In the following description, the same or corresponding parts will be denoted by the same reference numerals, and redundant descriptions will be omitted. Furthermore, unless otherwise specified, positional relationships such as top, bottom, left, and right will be based on the positional relationships shown in the drawings. Moreover, the dimensional ratios in the drawings are not limited to those shown.

[0022] In this specification, the term "layer" includes not only structures that are formed across the entire surface when observed in a plan view, but also structures that are formed in only a part of the surface. In this specification, the term "process" includes not only independent processes, but also processes that cannot be clearly distinguished from other processes, as long as their intended function is achieved.

[0023] In this specification, numerical ranges indicated using "~" represent a range that includes the numbers before and after "~" as the minimum and maximum values, respectively. In numerical ranges described in stages in this specification, the upper or lower limit of one stage of the numerical range may be replaced with the upper or lower limit of another stage of the numerical range. In numerical ranges described in this specification, the upper or lower limit of that numerical range may be replaced with the values ​​shown in the examples.

[0024] [First Embodiment] A method for manufacturing a semiconductor device according to the first embodiment will be described with reference to Figures 1 to 5. In the first embodiment, CUF (Capillary Under Fill) is used as the underfill material.

[0025] In the semiconductor device manufacturing method according to the first embodiment, a semiconductor substrate 10 and semiconductor chip components 20A and 20B are prepared, as shown in Figure 1(a). In Figure 1(a), multiple semiconductor chip components 20A and 20B are prepared, but in this manufacturing method, it is sufficient to prepare at least one semiconductor chip component 20A or 20B.

[0026] The semiconductor substrate 10 is a wiring substrate including wiring, and has a substrate body 12 and a plurality of electrodes 15 (a plurality of first electrodes). The substrate body 12 is, for example, a disc-shaped silicon wafer, or it may be an interposer substrate such as a silicon interposer. The diameter of the substrate body 12 may be, for example, 100 mm or more, 300 mm or more, or 450 mm or less. The substrate body 12 may also be in the shape of a rectangular panel.

[0027] The multiple electrodes 15 are electrodes connected to the wiring within the substrate body 12, and are electrodes formed on the surface 12a of the substrate body 12. The electrodes 15 are, for example, conductive pads, bumps, or a combination thereof. The electrodes 15 may include metal bumps (e.g., copper bumps). If the electrodes 15 are copper pillars, they may be subjected to Au plating, organic treatment (OSP), or inorganic treatment. Flux may not be used on the electrodes 15; that is, they may be flux-free. The width of the electrodes 15 may be 0.5 μm to 35 μm. The height of the electrodes 15 may be 0.5 μm to 100 μm or less. The pitch between the electrodes 15 may be 1 μm or more and 40 μm or less, 40 μm or less, 35 μm or less, 30 μm or less, 25 μm or less, or 20 μm or less. The pitch here refers to the distance between the centers of adjacent electrodes 15. In the example shown in Figure 1(a), the electrode 15 includes a group of electrodes connected to semiconductor chip component 20A and a group of electrodes connected to semiconductor chip component 20B.

[0028] The semiconductor chip component 20A has a chip body 21A and a plurality of electrodes 25 (a plurality of second electrodes) provided on the outer surface of the chip body 21A. The semiconductor chip component 20B has a chip body 21B and a plurality of electrodes 25 provided on the outer surface of the chip body 21B. The chip body 21A and the chip body 21B may each include one or more bare chips. Each electrode 25 is connected to the wiring of these bare chips. In the example of Figure 1(a), the electrode 25 is a metal bump having a conductive columnar portion 25a and a solder bump 25b provided on the columnar portion 25a. The surface of the solder bump 25b may be planar or curved, such as a hemisphere. The electrode 25 may be flux-free, similar to the electrode 15. The electrodes 25 are arranged at substantially the same pitch as the electrode 15 to which they are connected. The width of the electrode 25 may be 0.5 μm or more and 35 μm or less. The height of the electrode 25 may be 0.5 μm or more and 100 μm or less.

[0029] Once the semiconductor substrate 10 and semiconductor chip components 20A and 20B are prepared, the semiconductor chip components 20A and 20B are held by a flip-chip bonder (not shown), and as shown in Figure 1(a), the semiconductor chip components 20A and 20B are positioned on the semiconductor substrate 10 so that each electrode 25 of the semiconductor chip components 20A and 20B faces the corresponding electrode 15 of the semiconductor substrate 10. Then, the semiconductor chip components 20A and 20B are heated to a predetermined temperature (first temperature) by the flip-chip bonder and temporarily bonded to the semiconductor substrate 10. This temporary bonding is performed by TCB (Thermal Compression Bonding). The heating temperature during this temporary bonding may be 180°C or lower, 150°C or lower, 120°C or lower, or 100°C or lower, and is kept lower than the conditions for normal TCB. This temporary crimping temporarily connects the electrode 25 to the electrode 15 to such an extent that the semiconductor chip components 20A and 20B do not move relative to the semiconductor substrate 10. This temporary connection results in the electrodes being in contact with each other. The heating temperature during temporary crimping is preferably, for example, 25°C or higher, so that this temporary connection is achieved. As a result, the temporary connector 100A shown in Figure 1(b) is manufactured.

[0030] Once the temporary connector 100A is fabricated, as shown in Figure 1(c), underfill material 30 is filled into the gap between the semiconductor substrate 10 and the semiconductor chip components 20A and 20B. The underfill material 30 is a thermosetting resin composition containing a thermosetting component and may be liquid at room temperature (25°C). A portion of the underfill material 30 may protrude from the gap between the semiconductor substrate 10 and the semiconductor chip components 20A and 20B. The temporary connector 100B is then fabricated. At this stage, the underfill material 30 is in an uncured or semi-cured state.

[0031] The thermosetting components contained in the underfill material 30 are, for example, epoxy resin and its curing agent. Some or all of the epoxy resin constituting the thermosetting components may be liquid at 25°C. Examples of epoxy resins include diglycidyl ether type epoxy resin, novolac type epoxy resin, glycidyl ester type epoxy resin, glycidylamine type epoxy resin, linear aliphatic epoxy resin, and alicyclic epoxy resin. Diglycidyl ether type epoxy resin may be, for example, diglycidyl ether of bisphenol A, bisphenol F, bisphenol AD, bisphenol S, or hydrogenated bisphenol A. Novolac type epoxy resin is a compound epoxidized from a novolac resin formed from phenols and aldehydes, and an example of this is orthocresol novolac type epoxy resin. Glycidyl ester type epoxy resin may be, for example, glycidyl ester of phthalic acid or dimer acid. The glycidylamine-type epoxy resin may be, for example, triglycidyl-p-aminophenol, N,N,N',N'-tetraglycidyl-4,4'-diaminodiphenylmetadaminodiphenylmethane, or triglycidyl isocyanurate.

[0032] The curing agent for epoxy resins may include, for example, aromatic amines, phenolic compounds, or combinations thereof. Examples of aromatic amines that can be used as curing agents include diethyltoluenediamine, 1-methyl-3,5-diethyl-2,4-diaminobenzene, 1-methyl-3,5-diethyl-2,6-diaminobenzene, 1,3,5-triethyl-2,6-diaminobenzene, 3,3'-diethyl-4,4'-diaminodiphenylmethane, 3,5,3',5'-tetramethyl-4,4'-diaminodiphenylmethane, and dimethylthiotoluenediamine. Examples of phenolic compounds that can be used as curing agents include various novolac resins.

[0033] The underfill material 30 may contain an inorganic filler. The inorganic filler may be particles or short fibers (e.g., glass fibers) containing one or more selected from silica, calcium carbonate, clay, alumina, silicon nitride, silicon carbide, boron nitride, calcium silicate, potassium titanate, aluminum nitride, beryllia, zirconia, zircon, fossterite, steatite, spinel, mullite, titania, aluminum hydroxide, magnesium hydroxide, zinc borate, and zinc molybdate. The inorganic filler may be silica particles, and in particular, spherical silica particles. The inorganic filler may be surface-treated with a silane coupling agent or the like.

[0034] When the average particle size of the inorganic filler is small, it tends to be easier to fill the underfill material 30 between the semiconductor substrate 10 and the semiconductor chip components 20A and 20B. Therefore, from the viewpoint of adjusting the filling properties, it is preferable that the average particle size of the inorganic filler in the underfill material 30 is smaller than the average particle size of the inorganic filler in the sealing material used in the sealing process described later. The average particle size of the inorganic filler in the underfill material 30 may be 0.1 μm to 5.0 μm, 4.0 μm to 3.0 μm, or 2.0 μm or less. The average particle size of the inorganic filler can be the volume-based cumulative 50% diameter, which can be determined from the particle size distribution measured by laser diffraction.

[0035] When the inorganic filler content is small, the coefficient of linear expansion of the cured product when the underfill material 30 is cured tends to be large. From the viewpoint of adjusting the coefficient of linear expansion, the inorganic filler content in the underfill material 30 may be smaller than the inorganic filler content in the sealing material used in the sealing process. The inorganic filler content in the underfill material 30 may be 0% by mass or more, 5% by mass or more, 10% by mass or more, 20% by mass or more, 30% by mass or more, 40% by mass or more, or 50% by mass or more, based on the mass of the underfill material 30, and may also be 70% by mass or less, 67% by mass or less, less than 67% by mass, 65% by mass or less, or 60% by mass or less.

[0036] When the underfill material 30 is injected between the semiconductor substrate 10 and the semiconductor chip components 20A and 20B, the temporary connector 100B is placed in a reflow apparatus 300 (heating device) and heated to a predetermined temperature (second temperature) under pressure, as shown in Figure 2. The reflow apparatus 300 includes a chamber 301, a mounting table 302 on which the temporary connector 100B is placed, a heater 303 for heating the temporary connector 100B, and a cooling mechanism 304 for cooling the heater 303. The temperature at which the reflow apparatus 300 heats the temporary connector 100B (second temperature) is higher than the temperature at which temporary bonding occurs (first temperature), for example, 200°C or higher, and may be 250°C or higher. The heating temperature in the reflow apparatus 300 is preferably above the melting temperature of the electrode 25 (solder bump 25b). This high temperature melting causes the electrode 25 to melt, ensuring that the electrodes 15 and 25 are securely connected to each other. The temperature at which the temporary connector 100A described above was fabricated (first temperature) is lower than the heating temperature (second temperature) by the reflow apparatus 300. This heating by the reflow apparatus 300 may be performed over a period of time, for example, 3 to 20 minutes.

[0037] Furthermore, the pressure applied when pressurizing the temporary connector 100B by the reflow apparatus 300 may be, for example, 0.05 MPa to 1 MPa, or 0.4 MPa or less. Such pressurization promotes the heating connection between the electrode 15 and the electrode 25. The reflow apparatus 300 may also be a device capable of vacuuming. In this case, the heating and pressurizing treatment of the temporary connector 100B may be performed with the chamber 301 of the reflow apparatus 300 under vacuum. Vacuuming allows for the appropriate removal of gas (air) or moisture contained in the underfill material 30.

[0038] By heating and pressurizing the temporary connector 100B using the reflow apparatus 300 as described above, electrodes 15 and 25, which were in a temporary connection state, become permanently connected, and the two are firmly joined. Similarly, the underfill material 30 between the semiconductor substrate 10 and the semiconductor chip components 20A and 20B is heat-cured and becomes a hardened material. Furthermore, with the permanent connection of the electrodes, the electrodes become wet (solder forms an alloy layer). Thus, the temporary connector 100B becomes the connector 100C.

[0039] Once the connector 100C, in which electrodes 15 and 25 are firmly connected, is fabricated, as shown in Figure 3(a), the semiconductor chip components 20A and 20B are sealed with a sealing material on the substrate body 12 on the semiconductor substrate 10 to form a sealing layer 40. This fabricates the sealed body 200. As the sealing material used here, a general thermosetting sealing material can be used, and a thermosetting resin composition containing a thermosetting component and an inorganic filler may also be used. The sealing layer 40 is formed, for example, by compression molding of the sealing material, which is in powder form.

[0040] The thermosetting components contained in the sealing material may include epoxy resin and its curing agent, and examples of such components may be the same as those exemplified for the thermosetting components of the underfill material.

[0041] The encapsulant may contain an acrylic copolymer. An encapsulant containing an acrylic copolymer readily forms a cured product with an appropriate flexural modulus. The acrylic copolymer is a copolymer of two or more monomers, including monomers having an acryloyl group, monomers having a methacryloyl group, or a combination thereof.

[0042] The acrylic copolymer may have radical polymerizable functional groups. The acrylic copolymer having radical polymerizable functional groups is considered a component of the thermosetting component. The radical polymerizable functional groups may be, for example, acryloyl groups, methacryloyl groups, allyl groups, vinyl groups, or maleimide groups. The thermosetting component may include a radical polymerization initiator together with the acrylic copolymer having radical polymerizable functional groups.

[0043] The acrylic copolymer that can be included in the sealing material may contain an alkyl (meth)acrylate having a linear or branched alkyl group with 6 to 9 carbon atoms as a monomer unit, and the proportion may be 10% by mass or more and 40% by mass or less based on the amount of all monomer units in the acrylic copolymer. The alkyl (meth)acrylate having a linear or branched alkyl group with 6 to 9 carbon atoms may be one or more selected from n-hexyl (meth)acrylate, n-heptyl (meth)acrylate, n-octyl (meth)acrylate, n-nonyl (meth)acrylate, 2-methyloctyl (meth)acrylate, 2-ethylheptyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, isooctyl (meth)acrylate, and isononyl (meth)acrylate.

[0044] The sealing material may contain an elastomer. The sealing material containing an elastomer is likely to form a cured product having an appropriate flexural modulus. The elastomer may be, for example, polyisoprene, polybutadiene, 1,2-polybutadiene, styrene-butadiene rubber, acrylonitrile-butadiene rubber, polychloroprene, poly(oxypropylene), poly(oxytetramethylene) glycol, polyolefin glycol, poly-ε-caprolactone, silicone rubber, polysulfide rubber, fluororubber, or a combination of two or more selected from these. The elastomer may have a functional group that can react with the thermosetting component. The elastomer having the functional group is regarded as a component constituting the thermosetting component.

[0045] The elastomer may be a thermoplastic elastomer. The thermoplastic elastomer may be, for example, a polyester-based thermoplastic elastomer, a polybutadiene-based thermoplastic elastomer, an acrylic-based thermoplastic elastomer, or a combination of two or more selected from these.

[0046] In addition, the sealing material may further contain other components if necessary. Examples of other components include surfactants, coupling agents, curing accelerators, and ion trap agents. The same applies to the underfill material 30 described above.

[0047] When the sealing layer 40 is formed, as shown in (b) of FIG. 3, the sealing layer 40 may be polished and ground, and the upper surfaces of the semiconductor chip components 20A and 20B may be exposed from the sealing layer 40. If necessary, as shown in (c) of FIG. 3, electrodes 50 may be formed on the back surface 12b of the substrate body 12 of the semiconductor substrate 10. In the example of (c) of FIG. 3, the electrode 50 is formed from a conductive columnar portion 50a and a solder bump 50b. The solder bump 50b may be provided after the encapsulation body 200 is singulated.

[0048] As shown in (a) and (b) of FIG. 4, the encapsulation body 200 may be singulated by cutting the encapsulation body 200 along the dicing line DL. By singulation, a plurality of semiconductor devices 200A can be obtained from one encapsulation body 200. The semiconductor device 200A includes a wiring member 210 which is the singulated semiconductor substrate 10, semiconductor chip components 20A and 20B, an underfill portion 30A, a sealing layer 40, and electrodes 50. The wiring member 210 includes a wiring substrate 212 cut out from the substrate body 12 and a plurality of electrodes 15. The method of singulating the encapsulation body 200 is not particularly limited, and a normal method such as blade dicing may be used.

[0049] As described above, in the method for manufacturing a semiconductor device according to the present embodiment, the first temperature during temporary bonding is lower than the second temperature during reflow heating and is 180° C. or lower. Thereby, the first temperature when the semiconductor chip components 20A and 20B are first pressure-bonded (temporarily bonded) becomes lower than in the prior art, and warping hardly occurs in the semiconductor chip components 20A and 20B due to the heating during temporary bonding. On the other hand, in the subsequent reflow process, the temporarily connected body 100B filled with the underfill material 30 is heated at a second temperature higher than the first temperature of temporary bonding, so that the underfill material 30 is cured and the electrodes 25 of the semiconductor chip components 20A and 20B are permanently connected to the electrodes 15 of the semiconductor substrate 10. As described above, a semiconductor device with reduced warping and enhanced connection reliability can be manufactured.

[0050] In the semiconductor device manufacturing method according to this embodiment, when the temporary connector 100B is heated in the reflow apparatus 100, the temporary connector 100B is heated while being pressurized at a pressure of 0.05 MPa to 1 MPa. As a result, the semiconductor chip components 20A and 20B are firmly connected to the semiconductor substrate 10, and the electrode 25 is reliably connected to the electrode 15. Therefore, the connection reliability of the semiconductor device is further enhanced.

[0051] In the semiconductor device manufacturing method according to this embodiment, when heating the temporary connector 100B in the reflow apparatus 100, the reflow apparatus 300 housing the temporary connector 100B may be heated under vacuum. This ensures that air or moisture contained in the connection between the electrode 15 and the electrode 25 or in the voids of the underfill material 30 is reliably removed by vacuum. As a result, impurities are reduced, and the connection reliability of the semiconductor device is further improved.

[0052] In the semiconductor device manufacturing method according to this embodiment, it is preferable that electrodes 15 and 25 are flux-free. In this case, it is possible to prevent flux from remaining.

[0053] [Second Embodiment] Next, a method for manufacturing a semiconductor device according to the second embodiment will be described with reference to Figures 5 to 7. In the following, the differences from the first embodiment will be mainly described, and redundant explanations may be omitted. In the second embodiment, MUF (Mold Under Fill) is used as the underfill material.

[0054] In the semiconductor device manufacturing method according to the second embodiment, a semiconductor substrate 10 and semiconductor chip components 20A and 20B are prepared, as shown in Figure 5(a), similar to the first embodiment. Once the semiconductor substrate 10 and semiconductor chip components 20A and 20B are prepared, the semiconductor chip components 20A and 20B are held by a flip-chip bonder, similar to the first embodiment, and the semiconductor chip components 20A and 20B are positioned on the semiconductor substrate 10 such that each electrode 25 of the semiconductor chip components 20A and 20B faces the corresponding electrode 15 of the semiconductor substrate 10. Then, the semiconductor chip components 20A and 20B are heated to a predetermined temperature (first temperature) by the flip-chip bonder and temporarily bonded to the semiconductor substrate 10. The heating conditions can be the same as in the first embodiment. As a result, a temporary connector 100A is manufactured.

[0055] Once the temporary connector 100A is fabricated, a sealing material is prepared, and as shown in Figure 5(c), the semiconductor chip components 20A and 20B are sealed with the sealing material on the substrate body 12 on the semiconductor substrate 10 to form a sealing layer 40A. In the manufacturing method according to the second embodiment, when forming this sealing layer 40A, the same sealing material is also filled as an underfill material in the gap between the semiconductor substrate 10 and the semiconductor chip components 20A and 20B. The temporary connector 100B is then fabricated.

[0056] Once the semiconductor chip components 20A and 20B are sealed and underfill material is injected between the semiconductor substrate 10 and the semiconductor chip components 20A and 20B, the temporary connector 100B is placed in the reflow apparatus 300 and heated to a predetermined temperature (second temperature) under pressure, as shown in Figure 6. The temperature at which the reflow apparatus 300 heats the temporary connector 100B and the pressure applied can be the same as in the first embodiment. The sealed body 200 is then manufactured (see Figure 7(a), etc.).

[0057] As described above, by heating and pressurizing the temporary connector 100B with the reflow apparatus 300, in the second embodiment as well, the electrodes 15 and 25, which were in a temporary connection state, become permanently connected, and the two are firmly joined. Similarly, a portion of the sealing material, which is the underfill material between the semiconductor substrate 10 and the semiconductor chip components 20A and 20B, and the sealing material covering the semiconductor chip components 20A and 20B are heat-cured and become a cured product. As a result, the temporary connector 100B becomes the connector 100C.

[0058] Once the connector 100C, in which electrodes 15 and 25 are firmly connected, is fabricated, the sealing layer 40A is polished and ground to expose the upper surfaces of the semiconductor chip components 20A and 20B from the sealing layer 40A, as shown in Figures 7(a) and 7(b). If necessary, electrodes 50 may be formed on the back surface 12b of the substrate body 12 of the semiconductor substrate 10, as shown in Figure 7(b). In the example of Figure 7(b), the electrodes 50 are formed from a conductive columnar portion 50a and solder bumps 50b.

[0059] The encapsulant 200 may be cut along the dicing line DL to form individual pieces, as shown in Figure 7(c). By forming individual pieces, multiple semiconductor devices 200A can be obtained from a single encapsulant 200.

[0060] As described above, in the semiconductor device manufacturing method according to this embodiment, similar to the first embodiment, the first temperature during temporary crimping is lower than the second temperature during reflow heating, being 180°C or lower. As a result, the first temperature during the initial crimping (temporary crimping) of the semiconductor chip components 20A and 20B is lower than in conventional methods, and warping of the semiconductor chip components 20A and 20B is less likely to occur during heating by temporary crimping. On the other hand, in the subsequent reflow process, the temporary connector 100B filled with the underfill material is heated at a second temperature higher than the first temperature during temporary crimping, causing the underfill material to harden and the electrodes 25 of the semiconductor chip components 20A and 20B to be permanently connected to the electrodes 15 of the semiconductor substrate 10. As a result, it is possible to manufacture a semiconductor device with reduced warping and improved connection reliability.

[0061] In the semiconductor device manufacturing method according to this embodiment, the sealing material constituting the sealing layer 40A includes a material that functions as an underfilm and a material that functions as a covering for semiconductor chip components 20A and 20B. The temporary connection body including these is then heated and pressurized in a reflow apparatus 300. As a result, the two types of sealing materials described above can be heat-cured, and the permanent connection between electrode 15 and electrode 25 can also be made. Therefore, the manufacturing method according to the second embodiment can further improve manufacturing efficiency. In addition, the second embodiment can also achieve the same effects as the first embodiment.

[0062] Although embodiments of the present disclosure have been described above, the present invention is not limited to the embodiments described above, and modifications may be made as appropriate without departing from the spirit of the invention.

[0063] 10... Semiconductor substrate, 12... Substrate body, 15... Electrodes (multiple first electrodes), 20A, 20B... Semiconductor chip components, 25... Electrodes (multiple second electrodes), 30... Underfill material, 40... Sealing layer, 100A, 100B... Temporary connectors, 200A... Semiconductor device, 300... Reflow apparatus (heating device).

Claims

1. A method for manufacturing a semiconductor device, comprising the steps of: preparing a semiconductor substrate having a substrate body and a plurality of first electrodes, and at least one semiconductor chip component having a plurality of second electrodes; positioning the semiconductor chip component on the semiconductor substrate such that the plurality of second electrodes face the plurality of first electrodes, and heating the semiconductor chip component at a first temperature to temporarily press-bond the semiconductor chip component to the semiconductor substrate; filling the space between the temporarily pressed semiconductor chip component and the semiconductor substrate with underfill material to create a temporary connector; and heating the temporary connector at a second temperature, wherein the first temperature is lower than the second temperature and is 180°C or lower.

2. The method for manufacturing a semiconductor device according to claim 1, wherein the first temperature is 150°C or lower.

3. The method for manufacturing a semiconductor device according to claim 1 or 2, wherein the second temperature is 200°C or higher.

4. The method for manufacturing a semiconductor device according to any one of claims 1 to 3, wherein the step of heating the temporary connector at the second temperature is to heat the temporary connector while pressurizing it with a pressure of 0.05 MPa to 1 MPa.

5. The method for manufacturing a semiconductor device according to any one of claims 1 to 4, wherein in the step of heating the temporary connector at the second temperature, the heating is performed while the heating device housing the temporary connector is under vacuum.

6. A method for manufacturing a semiconductor device according to any one of claims 1 to 5, further comprising the step of sealing the semiconductor chip component after filling the underfill material.

7. The method for manufacturing a semiconductor device according to claim 6, wherein the semiconductor chip component is sealed after the temporary connector is heated at a second temperature.

8. The method for manufacturing a semiconductor device according to any one of claims 1 to 5, wherein in the step of filling the underfill material, the underfill material is filled when sealing the semiconductor chip component.

9. The method for manufacturing a semiconductor device according to any one of claims 1 to 8, wherein in the step of temporary crimping, the plurality of second electrodes are temporarily connected to the plurality of first electrodes, and in the step of heating the temporary connection at the second temperature, the plurality of second electrodes are permanently connected to the plurality of first electrodes.

10. The method for manufacturing a semiconductor device according to any one of claims 1 to 9, wherein the underfill material is a thermosetting resin composition containing a thermosetting component, and in the step of heating the temporary connector at the second temperature, the underfill is thermosetting.

11. The method for manufacturing a semiconductor device according to any one of claims 1 to 10, wherein the plurality of first electrodes and the plurality of second electrodes are flux-free.

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