Packaged device manufacturing method

Abstract

To provide a manufacturing method of a package device by which a workpiece encapsulated by a mold resin together with a device chip is thinned and flattened while suppressing occurrence of cracking or chipping and which divides the workpiece.SOLUTION: The present invention relates to a manufacturing method of a package device. A device chip is disposed on a first region of a workpiece, and the device chip and the workpiece are covered by a mold resin by supplying the mold resin to a second region, which is higher than the first region, and the first region. Thinning is performed by processing the mold resin to such a thickness that the second region of the workpiece is not exposed and that the device chip is not exposed, and the second region of the workpiece is exposed by polishing the mold resin. Further, the mold resin disposed in the first region and the second region are polished, a flat surface including the mold resin and the second region is formed on one side of the workpiece and the workpiece is divided, such that each package device is manufactured.SELECTED DRAWING: Figure 5

Description

[Technical Field]

[0001] The present invention relates to a method for manufacturing a packaged device, in which device chips are placed on a workpiece such as a semiconductor wafer and sealed with a molding resin, and the workpiece is divided into individual device chips to form packaged devices. [Background technology]

[0002] In recent years, there has been a remarkable trend toward smaller and thinner electronic devices, such as mobile phones and personal computers. Accordingly, the demand for smaller and more highly integrated device chips mounted on electronic devices continues to grow. In particular, a packaging technology for device chips has been attracting attention. This technology involves placing multiple device chips on a substrate, sealing them with a sealing material (mold resin), forming a redistribution layer (RDL), and then singulating them. This technology enables thinner chips, lower costs, and shorter wiring lengths.

[0003] However, if the entire surface of a substrate on which a device chip is mounted is covered and sealed with a mold resin, the shrinkage of the mold resin causes the entire substrate to warp, making subsequent processing of the substrate more difficult. Therefore, in order to reduce the amount of mold resin used and suppress substrate warping, a technique has been proposed in which a recess is formed in the substrate, a device chip is placed in the recess, the substrate is covered with mold resin, and then the substrate is ground to remove the mold resin outside the recess (see Patent Document 1). In this technique, grinding is continued until the substrate is exposed outside the recess.

[0004] Another technique has been proposed in which other components are placed in advance on the surface of a substrate other than the area where the device chip is to be mounted, the device chip is then placed in that area, and the substrate, along with the other components and the device chip, is sealed with a mold resin (see Patent Document 2). In this technique, the component placed on the substrate and sealed together with the substrate with a mold resin is called a gap filling component. In this technique, the mold resin placed on the gap filling component is ground away until the gap filling component is exposed.

[0005] These techniques reduce the amount of molding compound remaining on the substrate by grinding it away, thereby reducing the warpage of the substrate caused by the molding compound.The substrate that has been thinned and flattened by grinding is then further processed to separate the substrate into individual packaged devices. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Special Publication No. 2019-512168 [Patent Document 2] Japanese Patent Publication No. 2020-92147 Summary of the Invention [Problem to be solved by the invention]

[0007] The gap-filling material is made of a material such as silicon, which has a smaller coefficient of thermal expansion than the mold resin. This prevents warping of the substrate due to the gap-filling material. However, when the mold resin on the gap-filling material is removed and the exposed gap-filling material is ground, the gap-filling material is prone to chipping and cracking. Also, even in a technique in which a recess is formed in a substrate, the substrate is covered with mold resin, and then ground, when the mold resin on the substrate outside the recess is removed and the exposed substrate is ground, the substrate is prone to chipping and cracking.

[0008] This is thought to be because, when the gap filler or the substrate is exposed and ground, a fracture layer is formed in the gap filler or the substrate, and chips or cracks grow from the fracture layer due to stress caused by the mold resin. If chips or cracks occur, the resulting package device will be defective. Therefore, there is a need to establish a method for thinning the substrate by simultaneously processing the gap filler or the substrate and the mold resin without causing chips or cracks in the gap filler or the substrate.

[0009] The present invention has been made in consideration of such problems, and aims to provide a method for manufacturing a packaged device, which thins and flattens a workpiece sealed with a molded resin together with a device chip while suppressing the occurrence of cracks and chips, and then divides the workpiece. [Means for solving the problem]

[0010] According to one aspect of the present invention, a method for manufacturing a package device includes a workpiece preparation step of preparing a workpiece having a first region on one surface of which a plurality of mutually intersecting planned division lines are set, in which device chips are to be disposed in each of the sections defined by the planned division lines on the one surface, and a second region outside the first region; a device chip arrangement step of arranging the device chips on the first region of the workpiece; a resin molding step of supplying a molding resin to the second region, which is higher than the first region, and to the first region, to cover the device chips and the workpiece with the molding resin, after the workpiece preparation step and the device chip arrangement step; and a step of applying the molding resin from the one surface of the workpiece to a thickness such that the second region of the workpiece covered with the molding resin is not exposed and the device chips disposed in the first region are not exposed. Grinding with a grinding wheel a resin thinning step of thinning the workpiece by polishing the molding resin from the one surface side with a polishing pad after the resin thinning step to expose the second region of the workpiece, and further polishing the molding resin disposed in the first region and the second region with the polishing pad to form a flat surface including the molding resin and the second region on the one surface side of the workpiece; and a dividing step of dividing the workpiece along the planned dividing lines to manufacture individual packaged devices each including the device chip. In the resin thinning step, the workpiece covered with the molding resin is not ground. A method for manufacturing a packaged device is provided.

[0011] Preferably, the first region of the workpiece is constituted by a recess formed in the workpiece.

[0012] Alternatively, preferably, in the workpiece preparation step, a gap filling member having an opening is placed on a substrate to prepare the workpiece having on one side the first region located in the opening and the second region located outside the opening, and the gap filling member is formed from a material whose volume expansion rate when temperature increases or pressure decreases is smaller than that of the molding resin.

[0013] More preferably, the gap filling member has the same planar shape as the planar shape of the substrate, and the opening of the gap filling member is configured as a through-hole or a recess.

[0014] Preferably, the method further comprises, before the resin thinning step, a measuring step of measuring the thickness of the workpiece covered with the molding resin in order to determine the amount of molding resin to be removed in the resin thinning step, and in the measuring step, the thickness of the workpiece in the second region is measured from the other surface opposite to the one surface using a non-contact thickness gauge.

[0015] Also, preferably, in the resin molding step, the second region of the workpiece covered with the molding resin is higher than an upper end of the device chip disposed in the first region.

[0016] According to another aspect of the present invention, there is provided a method for manufacturing a package device, comprising: a workpiece preparation step of preparing a workpiece having a plurality of mutually intersecting planned division lines set on one surface thereof; a device chip arrangement step of arranging device chips on each of the areas partitioned by the planned division lines on the one surface of the workpiece; a resin molding step of supplying a molding resin to the one surface side of the workpiece to cover the device chips and the workpiece with the molding resin after the workpiece preparation step and the device chip arrangement step; and a step of applying the molding resin from the one surface side of the workpiece to a thickness that does not expose the device chips after the resin molding step. Grinding with a grinding wheela resin thinning step of thinning the mold resin by polishing the mold resin from the one surface side of the workpiece with a polishing pad to expose the device chip, and further polishing the mold resin and the device chip with the polishing pad to form a flat surface including the mold resin and the device chip; , applicable a dividing step of dividing the workpiece along the dividing lines to produce individual packaged devices each including the device chip. In the resin thinning step, the device chip and the workpiece covered with the molding resin are not ground. A method for manufacturing a packaged device is provided. [Effects of the Invention]

[0018] In a method for manufacturing a package device according to one aspect of the present invention, when the mold resin covering the workpiece is ground, grinding is stopped before the portion covered by the mold resin is exposed. Then, polishing is performed to completely remove the mold resin in a certain region, and further polishing is performed to form a flat surface including the remaining mold resin. In other words, grinding is not performed on the exposed portion where the mold resin has been removed, and therefore no fracture layer due to grinding is formed, and cracks or chips resulting from the fracture layer do not occur.

[0019] Therefore, one aspect of the present invention provides a method for manufacturing a packaged device, which thins and flattens a workpiece sealed with a molded resin together with a device chip while suppressing the occurrence of cracks and chips, and then divides the workpiece. [Brief explanation of the drawings]

[0020] [Figure 1] FIG. 1 is a perspective view schematically showing a grinding and polishing apparatus. [Figure 2] FIG. 2 is a plan view schematically showing a turntable, a grinding unit, and a polishing unit. [Figure 3] FIG. 3(A) is a perspective view schematically showing a workpiece according to a first example, and FIG. 3(B) is a perspective view schematically showing how a workpiece according to a second example is prepared. [Figure 4]Figure 4(A) is a cross-sectional view schematically showing the workpiece before the recess is formed, Figure 4(B) is a cross-sectional view schematically showing the workpiece according to the first example, and Figure 4(C) is a cross-sectional view schematically showing the workpiece in the device chip placement step. [Figure 5] Figure 5(A) is a cross-sectional view schematically showing the workpiece in the resin molding step, Figure 5(B) is a cross-sectional view schematically showing the ground workpiece, and Figure 5(C) is a cross-sectional view schematically showing the polished workpiece. [Figure 6] Figure 6(A) is a cross-sectional view schematically showing the workpiece at the first stage of the processing steps, Figure 6(B) is a cross-sectional view schematically showing the workpiece at the second stage of the processing steps, and Figure 6(C) is a cross-sectional view schematically showing the workpiece at the third stage of the processing steps. [Figure 7] FIG. 7(A) is a cross-sectional view schematically showing the workpiece in the fourth stage of the processing steps, and FIG. 7(B) is a cross-sectional view schematically showing the workpiece in the fifth stage of the processing steps. [Figure 8] Figure 8(A) is a cross-sectional view schematically showing the workpiece at the sixth stage of the processing steps, Figure 8(B) is a cross-sectional view schematically showing the workpiece at the seventh stage of the processing steps, and Figure 8(C) is a cross-sectional view schematically showing the workpiece at the division step. [Figure 9] Figure 9(A) is a cross-sectional view schematically showing the substrate of a workpiece according to the second example, Figure 9(B) is a cross-sectional view schematically showing a workpiece having an adhesive layer formed on its surface, and Figure 9(C) is a cross-sectional view schematically showing a workpiece according to the second example. [Figure 10] FIG. 10(A) is a cross-sectional view schematically showing the workpiece in the device chip disposing step, and FIG. 10(B) is a cross-sectional view schematically showing the workpiece on which the measuring step is carried out. [Figure 11]Figure 11(A) is a cross-sectional view schematically showing a workpiece on which a resin thinning step has been performed, Figure 11(B) is a cross-sectional view schematically showing a workpiece on which a polishing step has been performed, and Figure 11(C) is a cross-sectional view schematically showing a package device formed by performing a division step. [Figure 12] FIG. 12(A) is a cross-sectional view schematically showing the state in which a device chip is arranged on a workpiece according to the third example, and FIG. 12(B) is a cross-sectional view schematically showing the workpiece at the resin molding step. [Figure 13] Figure 13(A) is a cross-sectional view schematically showing a workpiece on which a resin thinning step has been performed, Figure 13(B) is a cross-sectional view schematically showing a workpiece on which a polishing step has been performed, and Figure 13(C) is a cross-sectional view schematically showing a package device formed by performing a division step. [Figure 14] 1 is a flowchart showing the flow of each step in a method of manufacturing a packaged device. DETAILED DESCRIPTION OF THE INVENTION

[0021] Hereinafter, an embodiment of the present invention will be described with reference to the accompanying drawings. First, a grinding and polishing apparatus that performs the resin thinning step and polishing step of the manufacturing method for a package device according to this embodiment will be described. Figure 1 is a perspective view that schematically shows a grinding and polishing apparatus 2 that grinds and polishes a workpiece. The grinding and polishing apparatus 2 performs grinding and polishing on a workpiece such as a silicon wafer.

[0022] The grinding / polishing apparatus 2 includes a base 4 that supports each of the components that make up the grinding / polishing apparatus 2. An opening 4a is formed in the upper surface of the front end of the base 4, and a transport unit (transport mechanism) 6 is provided inside this opening 4a. In addition, in a region further forward of the opening 4a, a cassette mounting table 4b on which a cassette 8 is placed and a cassette mounting table 4c on which a cassette 10 is placed are provided. For example, cassette 8 stores a plurality of workpieces before processing, and cassette 10 stores a plurality of workpieces after processing.

[0023] A tape-like protective member (not shown) for protecting the workpiece may be attached to the underside of the workpiece to be ground and polished by the grinding and polishing device 2. Specifically, the protective member includes a circular base material and an adhesive layer (glue layer) provided on the base material. The base material is made of a resin such as polyolefin, polyvinyl chloride, or polyethylene terephthalate, and the adhesive layer is made of an epoxy-based, acrylic-based, or rubber-based adhesive. The adhesive layer may also be made of an ultraviolet-curable resin that hardens when exposed to ultraviolet light.

[0024] The workpieces to which the protective members are attached are stored in a cassette 8 shown in Fig. 1, and the cassette 8 storing the plurality of workpieces is placed on the cassette mounting table 4b. Then, the transport unit 6 pulls out one workpiece from the cassette 8 and transports it.

[0025] An alignment mechanism 12 is provided diagonally behind the opening 4a of the grinding / polishing device 2. The workpieces housed in the cassettes 8 are transported to the alignment mechanism 12 by the transport unit 6. The alignment mechanism 12 then aligns and positions the workpieces in a predetermined position.

[0026] A transport unit (transport mechanism, loading arm) 14 that holds and rotates the workpiece is provided adjacent to the alignment mechanism 12. The transport unit 14 is equipped with a suction pad that adsorbs the top surface of the workpiece, and after the workpiece has been aligned by the alignment mechanism 12, it is adsorbed and held by the suction pad and transported rearward.

[0027] A disk-shaped turntable 16 is provided behind the transport unit 14. The turntable 16 is connected to a rotary drive source (not shown) such as a motor, and rotates around a rotation axis that is generally parallel to the Z-axis direction (vertical direction, up-down direction). In addition, on the turntable 16, a plurality of chuck tables (holding tables) 18 (four in FIG. 1 etc.) that hold workpieces are arranged at generally equal intervals along the circumferential direction of the turntable 16.

[0028] 2 includes a plan view schematically showing the four chuck tables 18 mounted on the turntable 16. The upper surfaces of the chuck tables 18 form holding surfaces 18a that hold the workpieces. The holding surfaces 18a are formed to have the same planar shape and approximately the same size as the workpieces. The holding surfaces 18a are connected to a suction source (not shown), such as an ejector, via a flow path (not shown) formed inside the chuck tables 18.

[0029] There is no limitation on the type or structure of the chuck table that holds the workpiece. For example, instead of chuck table 18, a chuck table that holds the workpiece by a mechanical method, an electrical method, or the like may be used.

[0030] Each chuck table 18 is connected to a rotary drive source (not shown) such as a motor, and rotates around a rotation axis that is approximately parallel to the Z-axis direction. The turntable 16 rotates counterclockwise (in the direction indicated by arrow α) in a plan view, and positions each chuck table 18 in the following order: transfer position A, rough grinding position B, finish grinding position C, polishing position D, and transfer position A. The transfer unit 14 then transfers the workpiece placed in the alignment mechanism 12 onto the chuck table 18 positioned at transfer position A.

[0031] A columnar support structure 20 is disposed behind the rough grinding position B and behind the finish grinding position C (behind the turntable 16). A Z-axis movement mechanism 22 is provided on the front side of the support structure 20. The Z-axis movement mechanism 22 includes a pair of Z-axis guide rails 24 disposed generally parallel to the Z-axis direction, and a plate-shaped Z-axis movement plate 26 is attached to the pair of Z-axis guide rails 24 in a state where it can slide along the Z-axis guide rails 24.

[0032] A nut portion (not shown) is provided on the rear surface side (back surface side) of Z-axis moving plate 26, and Z-axis ball screw 28, which is disposed generally parallel to Z-axis guide rail 24, is threadedly engaged with this nut portion. Furthermore, Z-axis pulse motor 30 is connected to one end of Z-axis ball screw 28. When Z-axis pulse motor 30 rotates Z-axis ball screw 28, Z-axis moving plate 26 moves in the Z-axis direction along Z-axis guide rail 24.

[0033] Grinding unit 32a, which performs rough grinding of the workpiece, is attached to the front side (surface side) of Z-axis moving plate 26, which is positioned above rough grinding position B. Meanwhile, grinding unit 32b, which performs finish grinding of the workpiece, is attached to the front side (surface side) of Z-axis moving plate 26, which is positioned above finish grinding position C. Movement of grinding units 32a and 32b in the Z-axis direction is controlled by Z-axis moving mechanism 22.

[0034] Each of the grinding units 32a and 32b includes a cylindrical housing 34 attached to the Z-axis moving plate 26. A cylindrical spindle 36 constituting a rotation axis is rotatably accommodated in the housing 34, and the lower end (tip) of the spindle 36 protrudes from the lower end of the housing 34.

[0035] A grinding wheel 38a for rough grinding the workpiece is attached to the lower end of the spindle 36 of the grinding unit 32a, and a grinding wheel 38b for finish grinding the workpiece is attached to the lower end of the spindle 36 of the grinding unit 32b.

[0036] Grinding wheels 38a, 38b attached to grinding units 32a, 32b have an annular base made of metal such as stainless steel, aluminum, etc. A plurality of grinding stones 38c, 38d for grinding the workpiece are arranged in an annular shape at approximately equal intervals on the underside of the base.

[0037] For example, the grinding wheels 38c, 38d are formed by fixing abrasive grains made of diamond, cBN (cubic boron nitride), or the like with a binder such as a metal bond, a resin bond, or a vitrified bond. However, there are no limitations on the material, shape, structure, size, etc. of the grinding wheels 38c, 38d. Furthermore, the number of grinding wheels 38c, 38d provided on the grinding wheels 38a, 38b can be set as desired.

[0038] A rotary drive source (not shown), such as a motor, is connected to the upper end (base end) of the spindle 36, and the grinding wheels 38a, 38b rotate around a rotation axis roughly parallel to the Z-axis direction by the rotational force transmitted from the rotary drive source via the spindle 36. Furthermore, a grinding fluid supply path (not shown) for supplying a grinding fluid, such as pure water, is provided inside the grinding units 32a, 32b. The grinding fluid is supplied toward the workpiece and grinding wheels 38c, 38d when the workpiece is ground.

[0039] Grinding unit 32a grinds the workpiece held by chuck table 18 positioned at rough grinding position B with grinding wheel 38c, thereby performing rough grinding of the workpiece. Grinding unit 32b grinds the workpiece held by chuck table 18 positioned at finish grinding position C with grinding wheel 38d, thereby performing finish grinding of the workpiece.

[0040] A pillar-shaped support structure 40 is disposed to the side of the polishing position D (to the side of the turntable 16). An XZ-axis movement mechanism 42 is provided on the front surface side (turntable 16 side) of the support structure 40. The XZ-axis movement mechanism 42 includes a pair of first guide rails 44 disposed generally parallel to the X-axis direction (front-rear direction), and a plate-shaped first moving plate 46 is attached to the pair of first guide rails 44 in a state where it can slide along the first guide rails 44.

[0041] A nut portion (not shown) is provided on the rear surface side of the first moving plate 46, and a first ball screw 48 disposed generally parallel to the first guide rail 44 is threadedly engaged with this nut portion. A first pulse motor 50 is connected to one end of the first ball screw 48. When the first pulse motor 50 rotates the first ball screw 48, the first moving plate 46 moves in the X-axis direction along the first guide rail 44.

[0042] A pair of second guide rails 52 arranged generally parallel to the Z-axis direction are provided on the front surface side (turntable 16 side) of the first moving plate 46. A plate-shaped second moving plate 54 is attached to the pair of second guide rails 52 in a state where it can slide along the second guide rails 52. A nut portion (not shown) is provided on the back surface side of the second moving plate 54, and a second ball screw 56 arranged generally parallel to the second guide rails 52 is screwed into this nut portion.

[0043] A second pulse motor 58 is connected to one end of the second ball screw 56. When the second pulse motor 58 rotates the second ball screw 56, the second moving plate 54 moves in the Z-axis direction along the second guide rail 52. A polishing unit 60 that polishes the workpiece is attached to the front surface side (turntable 16 side) of the second moving plate 54. The XZ-axis movement mechanism 42 controls the movement of the polishing unit 60 in the X-axis and Z-axis directions.

[0044] The polishing unit 60 includes a cylindrical housing 62 attached to the second moving plate 54. A cylindrical spindle 64 constituting a rotation axis is rotatably accommodated in the housing 62, with the lower end of the spindle 64 protruding from the lower end of the housing 62. A disc-shaped polishing pad 66 for polishing the workpiece is attached to the lower end of the spindle 64. A rotational drive source (not shown), such as a motor, is connected to the upper end (base end) of the spindle 64. The polishing pad 66 rotates around a rotational axis that is generally parallel to the Z-axis direction by the rotational force transmitted from the rotational drive source via the spindle 64.

[0045] The polishing unit 60 polishes the workpiece held by the chuck table 18 positioned at the polishing position D with the polishing pad 66. In this way, the workpiece is polished.

[0046] A transport unit (transport mechanism, unloading arm) 68 that holds and turns a workpiece is provided adjacent to the transport unit 14. The transport unit 68 is equipped with suction pads that suction-hold the upper surface of the workpiece, and transports the workpiece placed on the chuck table 18 located at transport position A by suction-holding it with the suction pads. Also, a cleaning unit (cleaning mechanism) 70 that cleans the processed workpiece with a cleaning liquid such as pure water is provided in front of the transport unit 68.

[0047] The workpieces cleaned by the cleaning unit 70 are transported by the transport unit 6 and stored in the cassette 10. That is, the cassette 10 stores a plurality of workpieces that have been processed by the grinding units 32a and 32b and the polishing unit 60.

[0048] A specific example will be described below of the operation of the grinding and polishing apparatus 2 when a workpiece is ground and polished by the grinding and polishing apparatus 2. When processing the workpiece, first, a plurality of unprocessed workpieces are stored in a cassette 8, and the cassette 8 is placed on the cassette mounting table 4b.

[0049] Next, one workpiece contained in cassette 8 is transported by transport unit 6 to alignment mechanism 12, which aligns the workpiece. After alignment, the workpiece is transported by transport unit 14 onto chuck table 18 located at transport position A.

[0050] The workpiece is placed on the chuck table 18 so that its lower surface faces the holding surface 18a and its upper surface is exposed upward. In this state, by applying negative pressure from a suction source to the holding surface 18a, the workpiece is sucked and held by the chuck table 18 via the protective member.

[0051] Next, the turntable 16 rotates, and the chuck table 18 holding the workpiece is positioned at the rough grinding position B. Then, the workpiece held by the chuck table 18 positioned at the rough grinding position B is ground by the grinding wheel 38c of the grinding unit 32a.

[0052] While the chuck table 18 and the grinding wheel 38a are rotated in a predetermined direction at a predetermined rotation speed, the grinding wheel 38a is lowered toward the chuck table 18 by the Z-axis movement mechanism 22. The speed at which the grinding wheel 38a is lowered is adjusted so that the multiple grinding stones 38c are pressed against the workpiece with an appropriate force.

[0053] When the lower surfaces of the rotating grinding wheels 38c come into contact with the workpiece, the workpiece is ground away. This grinding process is performed on the workpiece, thinning it down. When the workpiece is thinned down to a predetermined thickness, rough grinding of the workpiece is complete.

[0054] When the workpiece is ground by the grinding wheels 38c, a grinding fluid such as pure water is supplied to the workpiece and the grinding wheels 38c. The grinding fluid cools the workpiece and the grinding wheels 38c and washes away chips (grinding chips) generated by grinding the workpiece.

[0055] Next, the turntable 16 rotates, and the chuck table 18 holding the workpiece is positioned at the finish grinding position C. Then, the workpiece held by the chuck table 18 positioned at the finish grinding position C is ground by the grinding wheel 38d of the grinding unit 32b.

[0056] The configuration and operation of grinding unit 32b are similar to those of grinding unit 32a. However, the average grain size of the abrasive grains of grinding stones 38d provided on grinding wheel 38b is smaller than the average grain size of the abrasive grains of grinding stones 38c provided on grinding wheel 38a. The workpiece is ground by the lower surfaces of the grinding stones 38d provided on grinding wheel 38b coming into contact with the workpiece. Then, when the workpiece is thinned to a predetermined thickness, the finish grinding of the workpiece is completed.

[0057] Next, the turntable 16 rotates, and the chuck table 18 holding the workpiece is positioned at the polishing position D. Then, the workpiece held by the chuck table 18 positioned at the polishing position D is polished by the polishing unit 60. When the chuck table 18 is positioned at the polishing position D, the workpiece is positioned below the polishing unit 60.

[0058] The polishing pad 66 attached to the polishing unit 60 has a disk-shaped base made of a metal material such as stainless steel or aluminum. A polishing layer for polishing the workpiece is fixed to the underside of the base. For example, the polishing layer is formed in a disk shape with roughly the same diameter as the base and is attached to the underside of the base with an adhesive or the like. The underside of this polishing layer forms the polishing surface for polishing the workpiece.

[0059] The polishing layer is formed by incorporating abrasive grains such as silicon dioxide (SiO2), green carborundum (GC), white alundum (WA), etc. into a base member made of nonwoven fabric, urethane foam, etc. The abrasive grains contained in the polishing layer are, for example, abrasive grains with an average grain size of 0.1 μm to 10 μm. However, the material of the polishing layer and the grain size and material of the abrasive grains can be changed as appropriate depending on the material of the workpiece, etc.

[0060] When polishing a workpiece, first, the polishing pad 66 is positioned so that the polishing layer overlaps the entire workpiece. Then, while the chuck table 18 and the polishing pad 66 are rotated in a predetermined direction at a predetermined rotation speed, the polishing pad 66 is lowered toward the chuck table 18 by the XZ-axis movement mechanism 42. The speed at which the polishing pad 66 is lowered is adjusted so that the polishing layer is pressed against the workpiece with an appropriate force.

[0061] The workpiece is polished by pressing the polishing pad 66 against the workpiece while rotating. When the workpiece is thinned to a predetermined thickness, the polishing of the workpiece is complete. This polishing removes machining marks (cutting marks) and crushed layers formed on the workpiece when it was ground by the grinding units 32a and 32b, and also flattens the top surface of the polished workpiece.

[0062] When the workpiece is polished, no liquid (polishing liquid) such as a chemical solution (slurry) or pure water is supplied to the workpiece and polishing pad 66. In other words, the workpiece is processed by dry polishing using the polishing pad 66 containing abrasive grains.

[0063] However, the workpiece may also be processed by wet polishing. In this case, a polishing liquid that does not contain abrasive grains is supplied to the workpiece and polishing pad 66 when the workpiece is polished. Examples of polishing liquids that can be used include chemical liquids such as acidic polishing liquids and alkaline polishing liquids, as well as pure water. Examples of acidic polishing liquids include acidic solutions containing permanganate and the like, and examples of alkaline polishing liquids include alkaline solutions containing sodium hydroxide or potassium hydroxide.

[0064] In wet polishing, a chemical solution (slurry) containing abrasive grains may be supplied to the workpiece and polishing pad 66. The chemical solution (slurry) contains abrasive grains made of, for example, silicon oxide (SiO2), alumina (Al2O3), etc. as loose abrasive grains. In this case, the polishing pad 66 does not contain abrasive grains.

[0065] Next, the turntable 16 rotates, and the chuck table 18 holding the workpiece is positioned at the transfer position A. Then, the workpiece that has been ground and polished is transferred by the transfer unit 68 from the chuck table 18 positioned at the transfer position A to the cleaning unit 70. Then, the processed workpiece is cleaned by the cleaning unit 70.

[0066] Next, a method for manufacturing a packaged device according to this embodiment will be described. In this method, a device chip is disposed on a workpiece having a shape such as a flat plate, the device chip and the workpiece are covered with a molding resin, the molding resin is partially removed to form a flat surface, and the workpiece is divided to manufacture a packaged device. Figure 14 is a flowchart showing the flow of each step in the method for manufacturing a packaged device according to this embodiment.

[0067] First, a method for manufacturing a packaged device according to a first example of the present embodiment will be described. In the method for manufacturing a packaged device according to the first example, a packaged device is manufactured by processing a workpiece 11 shown in Fig. 3(A) etc. For example, the workpiece 11 is a wafer formed in a disk shape, and is made of a material such as silicon (Si), sapphire (Al2O3), gallium arsenide (GaAs), or silicon carbide (SiC).

[0068] The workpiece 11 has one surface (front surface) 11a and the other surface (back surface) 11b. A plurality of mutually intersecting planned division lines (streets) 13a, 13b are set on the one surface 11a of the workpiece 11, and these planned division lines 13a, 13b divide the one surface 11a of the workpiece 11 into a plurality of areas 15. For example, if the planned division lines 13a, 13b are set in a grid pattern, each area 15 will be rectangular.

[0069] Each of the regions 15 defined by the division lines 13a and 13b on one surface 11a of the workpiece 11 includes a first region 17a where a device chip is to be disposed and a second region 17b outside the first region 17a. The first region 17a is formed, for example, by a recess formed in the workpiece 11. Fig. 4(B) is a cross-sectional view schematically showing the workpiece 11 in which a recess 19a is formed in the first region 17a, and Fig. 4(A) is a cross-sectional view schematically showing the workpiece 11 before the recess 19a is formed.

[0070] 4(C) includes a cross-sectional view of a device chip 31 disposed in the first region 17a of the workpiece 11. The device chip 31 is, for example, an integrated circuit such as an IC (Integrated Circuit) or an LSI (Large Scale Integration), an image sensor such as a CCD (Charge Coupled Device) or a CMOS (Complementary Metal Oxide Semiconductor), or a passive component such as a capacitor or resistor. A protrusion 33 including a terminal portion 33a and an adhesive layer 33b is provided on the bottom surface of the device chip 31.

[0071] In the manufacturing method of the package device according to this embodiment, first, a workpiece preparation step S10 is performed to prepare a workpiece 11. As a method for preparing the workpiece 11 according to the first example, for example, a flat plate-shaped workpiece 11 as shown in Fig. 4(A) is prepared, and the workpiece 11 is processed in the first region 17a to form a recess 19a in the workpiece 11 as shown in Fig. 4(B).

[0072] For example, a resist film (not shown) is formed on one surface 11a of workpiece 11 in an area other than first region 17a of workpiece 11, and etching is performed on one surface 11a of workpiece 11 for a predetermined time. As a result, recesses 19a of a predetermined depth can be formed in first region 17a of workpiece 11.

[0073] However, the method of forming the recess 19a in the workpiece 11 is not limited to this. For example, an annular cutting blade having a blade thickness corresponding to the width of the recess 19a is prepared, and the rotating cutting blade is caused to cut into the first region 17a of the workpiece 11 to a predetermined depth. This allows the recess 19a to be formed to a predetermined depth. Note that the recess 19a may also be formed by other methods.

[0074] 3(A) and 4(B) is prepared by performing the workpiece preparation step S10, and then the device chip disposing step S20 is performed to dispose the device chip 31 on the first region 17a of the workpiece 11. FIG. 4(C) is a cross-sectional view schematically showing the workpiece 11 on which the device chip 31 is disposed on the first region 17a. For example, the device chip 31 is attached to the first region 17a of the workpiece 11 by the adhesive layer 33b of the protrusion 33.

[0075] Then, after the workpiece preparation step S10 and the device chip arrangement step S20, a resin molding step S30 is performed. Fig. 5(A) is a cross-sectional view schematically showing the workpiece 11 after the resin molding step S30 has been performed.

[0076] In the resin molding step S30, molding resin 35 is supplied to the first region 17a and to the second region 17b, which is higher than the first region 17a, to cover the device chip 31 and the workpiece 11. For example, the molding resin 35 is supplied from one surface 11a of the workpiece 11 in a heated and softened state, permeates every corner of the recess 19a in the first region 17a, and then hardens over time as heat is lost.

[0077] Here, the mold resin 35 is composed of an insulating synthetic resin such as epoxy resin, silicone resin, urethane resin, unsaturated polyester resin, acrylic urethane resin, or polyimide resin. It is preferable that the mold resin 35 be made of a highly heat-resistant material so that it can withstand processes such as the formation of the through electrodes 43 (see FIG. 7(B) and the like) described below. However, mold resins 35 made of highly heat-resistant materials tend to have a high shrinkage rate, which increases the stress acting on the workpiece 11, the device chip 31, and the like. This makes the polishing step S60 described below even more important.

[0078] After the resin molding step S30, the workpiece 11 is carried into the grinding and polishing apparatus 2 shown in Fig. 1, where the workpiece 11 is ground and polished in order to flatten one surface 11a of the workpiece 11 while reducing warpage of the workpiece 11 caused by stress generated in the molding resin 35. Next, the steps performed in the grinding and polishing apparatus 2 will be described in detail.

[0079] The grinding and polishing device 2 performs a resin thinning step S50. In the resin thinning step S50, the molding resin 35 is processed and thinned from one surface 11a of the workpiece 11 to a thickness that does not expose the second region 17b of the workpiece 11 covered with the molding resin 35 and does not expose the device chip 31 arranged in the first region 17a.

[0080] The resin thinning step S50 is performed by grinding using the grinding wheels 38c and 38d, for example. For example, the resin thinning step S50 may be performed in two stages: rough grinding the workpiece 11 with the grinding wheel 38c at the rough grinding position B, and then finish grinding the workpiece 11 with the grinding wheel 38d at the finish grinding position C.

[0081] In the grinding and polishing apparatus 2, the workpiece 11 is transferred onto the holding surface 18a of the chuck table 18 positioned at the transfer position A. At this time, the other surface (back surface) 11b of the workpiece 11 faces the holding surface 18a, and one surface (front surface) 11a is exposed upward. Then, the suction source of the chuck table 18 is activated, and the workpiece 11 is suction-held by the chuck table 18. Thereafter, the turntable 16 is rotated, and the chuck table 18, which is suction-holding the workpiece 11, is sent to the rough grinding position B.

[0082] At rough grinding position B, the grinding wheel 38c of the grinding unit 32a roughly grinds the molding resin 35 from one surface 11a of the workpiece 11. That is, the chuck table 18 and the grinding wheel 38a are rotated, and the grinding unit 32a is lowered at a relatively fast processing feed rate, bringing the grinding wheel 38c into contact with the molding resin 35 and roughly grinding the molding resin 35. Then, the rough grinding of the molding resin 35 is completed, leaving a predetermined thickness.

[0083] Next, the turntable 16 is rotated, and the chuck table 18, which holds the roughly ground workpiece 11 by suction, is sent to the finish grinding position C. At the finish grinding position C, the molding resin 35 is finish-ground from one surface 11a of the workpiece 11 by the grinding wheel 38d of the grinding unit 32b. That is, the chuck table 18 and the grinding wheel 38b are each rotated, and the grinding unit 32b is lowered at a relatively slow processing feed rate, so that the grinding wheel 38d comes into contact with the molding resin 35 and the molding resin 35 is finish-ground.

[0084] 5(B) is a cross-sectional view schematically showing the workpiece 11 after the resin thinning step S50 has been performed. The finish grinding of the molding resin 35 is completed so that the second region 17b of the workpiece 11 covered with the molding resin 35 and the device chip 31 are not exposed when the finish grinding is completed. The amount of molding resin 35 removed during rough grinding, the amount of molding resin 35 removed during finish grinding, and methods for determining these amounts will be described in detail later.

[0085] Regardless of the manufacturing method for a package device according to this embodiment, if at least one of the second region 17b of the workpiece 11 and the device chip 31 is exposed by the grinding process, a fractured layer with minute damage is formed on the exposed surface by the grinding wheel 38d. In this case, this fractured layer grows due to stress caused by the mold resin 35 partially remaining on the workpiece 11, and cracks occur in the workpiece 11, etc. Therefore, in the manufacturing method for a package device according to this embodiment, the workpiece 11 and the device chip 31 are not exposed by the grinding process.

[0086] After the resin thinning step S50, the polishing step S60 is performed. First, the turntable 16 is rotated to send the chuck table 18, which holds the finish-ground workpiece 11 by suction, to the polishing position D. Then, the chuck table 18 and the polishing pad 66 are rotated, and the polishing unit 60 is lowered to bring the polishing pad 66 into contact with the molding resin 35 covering the workpiece 11.

[0087] When the molding resin 35 is polished from one surface 11a of the workpiece 11 with the polishing pad 66, the molding resin 35 is removed from the second region 17b of the workpiece 11, exposing the second region 17b. Even if the polishing pad 66 comes into contact with the exposed second region 17b, a fractured layer is not formed in the second region 17b, unlike when the grinding wheels 38c and 38d come into contact. Therefore, stress caused by the remaining molding resin 35 does not cause cracks in the second region 17b.

[0088] In the polishing step S60, the molding resin 35 disposed in the first region 17a and the second region 17b are polished with a polishing pad 66 to form a flat surface including the molding resin 35 and the second region 17b on one surface 11a of the workpiece 11. FIG. 5C is a cross-sectional view schematically showing the workpiece 11 after the polishing step S60 has been performed. In the polishing step S60, when the polishing unit 60 has descended to a predetermined height, the descent of the polishing unit 60 is stopped, and polishing of the workpiece 11 is completed.

[0089] Depending on the thickness of the device chip 31 disposed in the first region 17a of the workpiece 11 and the depth of the recess 19a that constitutes the first region 17a, the upper surface of the device chip 31 may be exposed from the mold resin 35 when the polishing step S60 is performed. Even in this case, the grinding wheels 38c and 38d do not come into contact with the device chip 31, so cracks do not occur in the device chip 31. Then, a flat surface is formed by the second region 17b of the workpiece 11, the mold resin 35, and the device chip 31.

[0090] After the resin thinning step S50 and the polishing step S60 are performed, the turntable 16 is rotated to send the chuck table 18 to the transfer position A, the workpiece 11 is cleaned in the cleaning unit 70, and is then removed from the grinding and polishing apparatus 2. Various further processes are performed on the workpiece 11 removed from the grinding and polishing apparatus 2. Next, an example of processing performed on the workpiece 11 after the resin thinning step S50 and the polishing step S60 will be described as processing step S70.

[0091] 6(A) is a cross-sectional view schematically showing the workpiece 11 in the first stage of processing step S70. In this first stage, the workpiece 11 is turned upside down so that one surface (front surface) 11a faces downward and the other surface (back surface) 11b faces upward. Then, an insulator layer 37 is formed on the other surface 11b of the workpiece 11.

[0092] The insulating layer 37 is, for example, a silicon oxide film, a silicon nitride film, a resin film, or the like. However, the material of the insulating layer 37 is not limited to these. The insulating layer 37 is formed by, for example, a CVD method, a sputtering method, a spin coating method, or the like.

[0093] 6(B) is a cross-sectional view schematically illustrating the workpiece 11 in the second stage of processing step S70. In this second stage, a resist film 39 is formed on the insulator layer 37 to expose the protrusion 33 of the device chip 31. A material that will become the resist film is deposited on the insulator layer 37, and light is irradiated onto predetermined regions of the material to partially alter the material. A developer is then applied to remove some of the material, thereby forming a patterned resist film 39. The resist film 39 has openings 41 formed at predetermined positions.

[0094] 6(C) is a cross-sectional view schematically illustrating the workpiece 11 in the third stage of processing step S70. In this third stage, the area of ​​the insulator layer 37 exposed in the opening 41 of the resist film 39 is etched to thin the insulator layer 37 to a predetermined thickness. This step is performed by, for example, reactive ion etching (RIE). However, the step of removing a portion of the insulator layer 37 may be performed by other methods.

[0095] 7(A) is a cross-sectional view schematically showing the workpiece 11 in the fourth stage of processing step S70. In this fourth stage, etching is further carried out to form through-holes 41a that reach the terminal portions 33a of the device chip 31. The etching in this fourth stage may be performed by, for example, the Bosch process or reactive ion etching.

[0096] The resist film 39 used in the etching performed in the third stage may be used as is for the etching performed in the fourth stage. Alternatively, after the etching performed in the third stage is completed, the resist film 39 may be removed, a new resin member may be supplied to the other surface 11b of the workpiece 11, and a predetermined region of the resin member may be irradiated with light to cause a developer to act thereon, thereby forming a new resist film. In this case, a resist film suitable for the etching performed in the fourth stage may be used.

[0097] 7(B) is a cross-sectional view schematically showing the workpiece 11 in the fifth stage of processing step S70. In this fifth stage, the resist film 39 is removed, and an electrode material is supplied to the through-holes 41a formed in the fourth stage to form through-electrodes 43 connected to the terminal portions 33a of the device chip 31. The through-electrodes 43 are, for example, copper through-electrodes formed by an electroplating filling process. However, the method for forming the through-electrodes 43 is not limited to this.

[0098] The device chip 31 does not necessarily have the protrusion 33 including the terminal portion 33a, and may have a terminal of another configuration connected to the through electrode 43. For example, the device chip 31 may have a structure in which a plurality of copper pillars are formed on the surface, the spaces between the pillars are filled with a resin film such as polyimide, and the surface side is flattened with a surface planer, instead of the protrusion 33. In this case, the device chip 31 does not have the protrusion 33, and the through electrode 43 is connected to the pillar exposed from the resin film. That is, the pillar functions as the terminal portion.

[0099] 8(A) is a cross-sectional view schematically showing workpiece 11 in a sixth stage of processing step S70. In this sixth stage, a wiring layer 45 is formed on the other surface (back surface) 11b of workpiece 11. Wiring layer 45 may be formed from conductors 47, 49 made of a metal member patterned into a predetermined shape, and an insulating film surrounding conductors 47, 49.

[0100] More specifically, for example, a metal film is formed on the other surface 11b of the workpiece 11, the metal film is patterned into a predetermined shape by a photolithography process, the metal film is covered with an insulating film, and openings are formed in the insulating film at predetermined positions to expose the metal film. Alternatively, an insulating film is formed on the other surface 11b of the workpiece 11, the insulating film is patterned into a predetermined shape, and a metal member is disposed in the area where the insulating film has been removed. The wiring layer 45 is formed on the other surface 11b of the workpiece 11 by these methods or other methods.

[0101] 8(B) is a cross-sectional view schematically illustrating the workpiece 11 in the seventh stage of processing step S70. In this seventh stage, the terminal portion 51 of the new device chip 53 is connected to the conductor portions 47 and 49 of the wiring layer 45, and the new device chip 53 is disposed on the other surface 11b of the workpiece 11. This ultimately results in a packaged device including multiple device chips 31 and 53. The device chip 53 may then be sealed with a new molding resin.

[0102] The processing step S70 described above is one example. After the resin thinning step S50 and the polishing step S60 have been performed, the workpiece 11 is subjected to any processing, and device chips 31, 53 are packaged in each of the areas 15 defined by the division lines 13. In the method for manufacturing a packaged device according to this embodiment, a dividing step S80 is then performed in which the workpiece 11 is divided along the division lines 13 to manufacture individual packaged devices 55 each including the device chips 31, 53.

[0103] 8(C) is a cross-sectional view schematically showing the workpiece 11 undergoing the dividing step S80. The dividing step S80 is performed, for example, by a cutting device equipped with a cutting unit 72. The cutting device includes a chuck table (not shown) configured similarly to the chuck table 18 of the grinding / polishing device 2, and the cutting unit 72 that cuts the workpiece 11 held by the chuck table.

[0104] The cutting unit 72 includes a spindle 74 whose base end is connected to a rotary drive source, and a cutting blade 76 fixed to the tip end of the spindle 74. The cutting blade 76 includes an annular cutting edge made up of a grinding wheel portion, and the cutting blade 76 also rotates when the spindle 74 is rotated. When the cutting edge of the rotating cutting blade 76 cuts into the workpiece 11, the workpiece 11 is cut.

[0105] In the dividing step S80, the cutting unit 72 is lowered so that the lowest end of the rotating cutting blade 76 reaches a height position below the lower end of the workpiece 11, and the chuck table and the cutting unit 72 are moved relatively along the processing feed direction. This cuts the workpiece 11 along the planned dividing lines 13, dividing the workpiece 11. When the workpiece 11 has been divided along all of the planned dividing lines 13 set on the workpiece 11, individual package devices 55 are manufactured.

[0106] As described above, in the method for manufacturing a package device according to this embodiment, when the mold resin 35 is partially removed to suppress warpage of the workpiece 11, the second region 17b of the workpiece 11 and the device chip 31 are not ground. Therefore, a fractured layer caused by grinding is not formed in the workpiece 11, etc., and cracks caused by stress generated in the mold resin 35, etc., do not grow and form from the fractured layer.

[0107] The first example described above is a silicon wafer or the like in which the first region 17a is formed by the recess 19a and the outside of the first region 17b is the second region 17b, and the workpiece 11 is prepared in the workpiece preparation step S10. However, the workpiece prepared in the workpiece preparation step S10 may be prepared by other methods, for example, by placing a gap filling member on a disk-shaped silicon wafer or the like. Next, a second example of the method for manufacturing a package device according to this embodiment will be described.

[0108] 3(B) is a perspective view schematically illustrating a workpiece preparation step S10 in the manufacturing method of a package device according to the second example. In the workpiece preparation step S10, a gap filling member 25 having a through hole (opening) 19b is placed on and integrated with a substrate 23 to prepare a workpiece 21 having, on one surface thereof, a first region located in the through hole (opening) 19b and a second region located outside the through hole (opening) 19b.

[0109] Here, substrate 23 is made of a material such as silicon, similar to workpiece 11 described above. Fig. 9(A) is a cross-sectional view schematically showing substrate 23. As shown in Fig. 9(A) and other figures, conductor portions 59 and a wiring layer 57 may be formed on one surface (front surface) 23a of substrate 23. Wiring layer 57 includes, for example, a metal layer having a predetermined pattern made of a conductive film such as copper or aluminum, and an insulator layer made of a silicon oxide film, a silicon nitride film, or the like.

[0110] In order to integrate the substrate 23 with the gap filling member 25, an adhesive layer is provided on one or both of one surface 23a of the substrate 23 and the other surface (back surface) 25b of the gap filling member 25. Fig. 9(B) is a cross-sectional view schematically showing the substrate 23 on which an adhesive layer 61 is provided on one surface 23a.

[0111] Furthermore, gap filling member 25 is made of, for example, the same material as substrate 23, such as silicon, and has the same planar shape as that of substrate 23. Gap filling member 25 has a plurality of through holes 19b penetrating from one surface 25a to the other surface 25b, or recesses (not shown) opening on one surface 25a formed therein.

[0112] This through hole 19b or recess (not shown) accommodates a device chip 65 (see FIGS. 10A and 10B), as will be described later. That is, when the substrate 23 and the gap filling member 25 are combined to form the workpiece 21, this through hole 19b or recess defines a first region 17c of the workpiece 21. The outside of the first region 17c of the workpiece 21 becomes a second region 17d. The through hole 19b or recess is formed in the disk-shaped wafer by etching or another method.

[0113] Here, gap filling member 25 is a member used to partially remove mold resin 69 (see FIG. 10(B)) supplied to workpiece 21, with the aim of reducing warpage caused by mold resin 69 on workpiece 21. Therefore, to prevent warpage of workpiece 21 caused by gap filling member 25 instead of mold resin 69, gap filling member 25 is preferably formed from a material whose volume expansion rate when temperature rises or pressure drops is smaller than that of mold resin 69.

[0114] In workpiece preparation step S10, as shown in Fig. 3(B), gap filling member 25 is placed on and fixed to substrate 23 to prepare workpiece 21 in which substrate 23 and gap filling member 25 are integrated. Fig. 9(C) is a cross-sectional view schematically showing workpiece 21 prepared by integrating substrate 23 and gap filling member 25.

[0115] 9(C), the through hole (opening) 19b of the gap filling member 25 is formed in the gap filling member 25 so as to be located in a region that will become the first region 17c of the workpiece 21 when the substrate 23 and the gap filling member 25 are integrated to form the workpiece 21. Conversely, by placing the gap filling member 25 having the through hole (opening) 19b on the substrate 23, the workpiece 21 is formed to have, on one surface 21a, the first region 17c located in the through hole (opening) 19b and the second region 17d located outside the through hole (opening) 19b. The first region 17c may be formed as a recess formed in the gap filling member 25.

[0116] Next, a device chip disposing step S20 is performed in which a device chip 65 is disposed on the first region 17c of the workpiece 21. Fig. 10(A) is a cross-sectional view schematically showing the workpiece 21 on which the device chip 65 is disposed in the device chip disposing step S20. For example, a terminal portion 67 of the device chip 65 is connected to the wiring layer 57 of the substrate 23. Note that the device chip 65 may have a copper pillar surrounded by a resin film instead of the terminal portion 67, and the pillar may be connected to the wiring layer 57 of the substrate 23.

[0117] In the method for manufacturing a packaged device according to this embodiment, it is not necessary to perform the device chip arrangement step S20 after the workpiece preparation step S10. For example, the workpiece preparation step S10 and the device chip arrangement step S20 may be performed simultaneously, or the workpiece preparation step S10 may be performed after the device chip arrangement step S20.

[0118] In other words, before the gap filling member 25 is placed on the substrate 23, the device chip 65 may first be disposed on the substrate 23 at a position that will become the first region 17c of the workpiece 21. Then, the gap filling member 25 may be placed on the substrate 23 so as to accommodate the device chip 65 inside the through-hole (opening) 19b, thereby preparing the workpiece 21. In this case, it can be said that the device chip disposing step S20 is completed simultaneously with the workpiece preparing step S10.

[0119] After the workpiece preparation step S10 and the device chip arrangement step S20, a resin molding step S30 is performed in which a molding resin 69 is supplied to the second region 17d and the first region 17c to cover the device chip 65 and the workpiece 21 with the molding resin 69. Fig. 10(B) is a cross-sectional view schematically showing the workpiece 21 covered with the molding resin 69.

[0120] When the resin molding step S30 is performed, the second region 17d of the workpiece 21, which is formed by one surface (surface) 25a of the gap filling member 25, is higher than the first region 17c of the workpiece 21, which is formed by the through-hole (opening) 19b of the gap filling member 25. Next, the workpiece 21 is sent to the grinding and polishing device 2, where the resin thinning step S50 and the polishing step S60 are performed.

[0121] Before the resin thinning step S50 is performed, a measuring step S40 may be performed in the grinding and polishing apparatus 2 or outside the grinding and polishing apparatus 2 to measure the thickness of the workpiece 21 covered with the molding resin 69. In the measuring step S40, the thickness of the workpiece 21 is measured to determine the amount of molding resin 69 to be removed in the resin thinning step S50, i.e., to determine the amount of molding resin 69 to be ground by the grinding wheels 38c, 38d.

[0122] Fig. 10(B) is a cross-sectional view that schematically shows the measurement step S40. In the measurement step S40, for example, a non-contact thickness gauge 78 shown in Fig. 10(B) is used. The non-contact thickness gauge 78 measures the thickness of the workpiece 21 by, for example, irradiating the workpiece 21 with light such as infrared light having a wavelength that can pass through the workpiece 21 from the other surface (back surface) 21b side and detecting the reflected light.

[0123] Here, when an attempt is made to irradiate light from the non-contact thickness measuring device 78 onto one surface (front surface) 21a of the workpiece 21, the light is blocked by the mold resin 69. Therefore, the non-contact thickness measuring device 78 irradiates light onto the workpiece 21 from the other surface 21b (other surface 23b of the substrate 23) side of the workpiece 21.

[0124] The light emitted from the non-contact thickness measuring device 78 travels so as to pass through the workpiece 21. Thereafter, when the light reaches one surface 21a of the workpiece 21 (one surface 25a of the gap filling member 25) on which the molding resin 69 is placed, the light is reflected and travels in the opposite direction through the workpiece 21. The reflected light then reaches the other surface 21b of the workpiece 21 (the other surface 23b of the substrate 23) and returns to the non-contact thickness measuring device 78.

[0125] In particular, in the measuring step S40, it is preferable to measure the thickness of the workpiece 21 in the second region 17d of the workpiece 21 using a non-contact thickness measuring device 78. Then, it is preferable to determine the amount of molding resin 69 to be removed (grinded away) in the resin thinning step S50 according to the thickness of the workpiece 21 in the second region 17d measured in the measuring step S40.

[0126] For example, the removal amount (grinding amount) of molding resin 69 is determined so that second region 17d is not exposed in workpiece 21 when molding resin 69 is ground in resin thinning step S50, and so that second region 17d can be exposed in the polishing step S60 that is performed subsequently. In particular, it is preferable to determine the removal amount (grinding amount) in rough grinding performed by grinding unit 32a of grinding / polishing device 2 and the removal amount (grinding amount) in finish grinding performed by grinding unit 32b.

[0127] For example, if the molding resin 69 is formed on the workpiece 21 to a thickness of about 100 μm, it is recommended to remove the molding resin 69 to a thickness of about 78 μm in the rough grinding and then remove the molding resin 69 to a thickness of about 20 μm in the finish grinding. In this case, when the resin thinning step S50 is completed, the molding resin 69 will remain in the second region 17d of the workpiece 21 to a thickness of about 2 μm.

[0128] In other words, in resin thinning step S50, rough grinding is performed so that molding resin 69 is ground to a position higher than holding surface 18a of chuck table 18 by a height equal to the thickness of workpiece 21 plus 22 μm. Then, finish grinding is performed so that molding resin 69 is ground to a position higher than holding surface 18a by a height equal to the thickness of workpiece 21 plus 2 μm. Figure 11(A) is a cross-sectional view schematically showing workpiece 21 after resin thinning step S50 has been performed.

[0129] After the resin thinning step S50 is performed, the polishing step S60 is performed. Fig. 11(B) is a cross-sectional view schematically showing the workpiece 21 after the polishing step S60 has been performed. In the polishing step S60, for example, the molding resin 69 remaining in the second region 17d of the workpiece 21 is polished and removed by a polishing pad 66 to expose the second region 17d of the workpiece 21.

[0130] Then, the polishing of the workpiece 21 is further continued until the workpiece 21 is thinned by about 1 μm, and a flat surface made up of the molding resin 69 remaining in the first region 17c and the second region 17d is formed on one surface 21a of the workpiece 21. Note that the amount of molding resin 69 removed (grinding amount) in the resin thinning step S50 and the amount of molding resin 69 removed (polishing amount) in the polishing step S60 may be applied to the manufacturing method of the package device according to the first example described above.

[0131] Here, a detailed description will be given of the depth of the through hole (opening) 19b of the gap filling member 25, i.e., the difference in height between the second region 17d and the first region 17c. The depth of the through hole (opening) 19b of the gap filling member 25 is preferably set so that when the device chip 65 is disposed in the first region 17c formed by the through hole (opening) 19b, the upper end of the device chip 65 does not protrude from the through hole 19b.

[0132] That is, it is preferable that the depth of the through hole 19b is greater than the height of the device chip 65. In other words, it is preferable that the height of the second region 17d of the workpiece 21 is greater than the height of the first region 17c by a difference that exceeds the thickness of the device chip 65. For example, if the thickness of the device chip 65 is 250 μm, it is preferable that the depth of the through hole (opening) 19b of the gap filling member 25 is about 400 μm.

[0133] However, the depth of the through-hole (opening) 19b may be equal to or smaller than the height of the device chip 65. The depth of the through-hole 19b is preferably set so that the device chip 65 is not exposed from the molding resin 69 when the resin thinning step S50 is performed, and so that the second region 17d of the workpiece 21 is exposed when the polishing step S60 is performed. In this case, the device chip 65 is exposed from the molding resin 69 in the polishing step S60.

[0134] In addition, in the workpiece 11 of the manufacturing method of the packaged device according to the first example described above, the depth of the recess 19a constituting the first region 17a (the height of the second region 17b relative to the first region 17a) may be determined in a similar manner. More specifically, it is preferable that the depth be set so that when the device chip 31 is housed in the recess 19a, the upper end of the device chip 31 does not protrude from the recess 19a. In other words, it is preferable that the depth of the recess 19a is greater than the height of the device chip 31.

[0135] For example, if the workpiece 11 is a wafer with a thickness of 775 μm and the device chip 31 is 250 μm thick, the depth of the recess 19a should be 400 μm. However, the depth of the recess 19a may be the same as or smaller than the height of the device chip 31. The depth of the recess 19a should be set so that the device chip 31 is not exposed from the molding resin 35 when the resin thinning step S50 is performed, and so that the second region 17b of the workpiece 11 is exposed when the polishing step S60 is performed.

[0136] Returning to the description of the method for manufacturing a package device according to the second example, after polishing step S60 is performed, predetermined processing is performed on workpiece 21, and finally dividing step S80 is performed to divide workpiece 21 along planned dividing lines 13. This results in the formation of individual package devices 71 as shown in FIG. 11(C).

[0137] If the molding resin 69 formed in the second region 17d of the workpiece 21 is removed by grinding alone, a fractured layer is formed on one surface (front surface) 25a of the gap filling member 25. In this case, cracks propagate from the fractured layer due to the influence of stress caused by the molding resin 69 remaining in the workpiece 21. In contrast, in the manufacturing method for a package device according to the second example, the gap filling member 25 of the workpiece 21 is not ground, and a fractured layer is not formed in the gap filling member 25, thereby suppressing the occurrence of cracks.

[0138] Here, in the manufacturing methods of package devices according to the first and second examples described above, the second regions 17b, 17d are higher than the first regions 17a, 17c in which the device chips 31, 65 are disposed in the workpieces 11, 21. The mold resins 35, 69 are ground and polished to expose the second regions 17b, 17d.

[0139] However, in the method for manufacturing a packaged device according to this embodiment, there may be no difference in height between the area where the device chip is disposed and the area outside of that area. Furthermore, when the workpiece is ground and polished, the workpiece may not be exposed, and only the device chip may be exposed from the molding resin. Next, a third example of the method for manufacturing a packaged device according to this embodiment will be described.

[0140] First, a workpiece preparation step S10 is performed to prepare a workpiece having a plurality of mutually intersecting planned dividing lines set on one surface. Fig. 12(A) includes a cross-sectional view schematically showing a workpiece 73 in a manufacturing method for a package device according to a third example. The workpiece 73 is, for example, a wafer made of a material such as silicon.

[0141] 12(A), a conductor portion 77 and a wiring layer 75 may be formed on one surface (front surface) 73a of the workpiece 73 prepared in the workpiece preparation step S10. The wiring layer 75 includes a metal layer having a predetermined pattern and made of a conductive film such as copper or aluminum, and an insulator layer made of a silicon oxide film, a silicon nitride film, or the like.

[0142] Next, a device chip disposing step S20 is performed in which device chips 81 are disposed on each of the areas defined by the dividing lines 13 on one surface 73a of the workpiece 73. Fig. 12(A) is a cross-sectional view schematically showing the workpiece 73 on which the device chips 81 are disposed. For example, terminal portions 83 of the device chips 81 are connected to the wiring layer 75 of the workpiece 73.

[0143] After the workpiece preparation step S10 and the device chip arrangement step S20, a resin molding step S30 is performed in which a molding resin 85 is supplied to one surface (front surface) 73a of the workpiece 73 to cover the device chip 81 and the workpiece 73 with the molding resin 85. Fig. 12(B) is a cross-sectional view schematically showing the workpiece 73 covered with the molding resin 85.

[0144] After the resin molding step S30, the workpiece 73 is sent to the grinding and polishing device 2, where the resin thinning step S50 and the polishing step S60 are performed. In the resin thinning step S50, the workpiece 73 is placed on the chuck table 18 with the other surface (back surface) 73b facing downward, and the molding resin 85 is ground from one surface of the workpiece 73 with grinding wheels 38c, 38d to a thickness that does not expose the device chip 81. For the procedure of the resin thinning step S50, refer to the explanation of the resin thinning step S50 in the manufacturing method of a packaged device according to another example, as appropriate.

[0145] 13(A) is a cross-sectional view schematically showing the workpiece 73 after the resin thinning step S50 has been performed. As shown in FIG. 13(A), a small thickness of the molding resin 85 is left on the device chip 81. This thickness of the molding resin 85 is set to a thickness that will be sufficiently removed in the polishing step S60, which will be described next, and the resin thinning step S50 is performed so that this thickness of the molding resin 85 remains.

[0146] For example, if the molding resin 85 is removed to a thickness of about 3 μm in the polishing step S60, the molding resin 85 may be ground in the resin thinning step S50 so that the molding resin 85 remains on the device chip 81 to a thickness of about 2 μm.

[0147] After the resin thinning step S50, a polishing step S60 is performed. Fig. 13(B) is a cross-sectional view schematically showing the workpiece 73 after the polishing step S60 has been performed. In the polishing step S60, the molding resin 85 is polished from one surface (front surface) 73a of the workpiece 73 with a polishing pad 66 to expose the device chips 81 from the molding resin 85.

[0148] In the polishing step S60, the mold resin 85 remaining on the outside of the device chip 81 and the device chip 81 are polished with the polishing pad 66 to form a flat surface including the mold resin 85 and the device chip 81. Here, the grinding wheels 38c and 38d are not in contact with the device chip 81, so no fractured layer is formed in the device chip 81. Therefore, cracks caused by stress generated in the mold resin 85 remaining around the device chip 81 do not extend from the fractured layer.

[0149] Thereafter, various processes may be performed on the workpiece 73 removed from the grinding and polishing apparatus 2. Finally, a dividing step S80 is performed to divide the workpiece 73 along the planned dividing lines 13. FIG. 13(C) is a cross-sectional view schematically showing package devices 87 manufactured by dividing the workpiece 73 in the dividing step S80. When the dividing step S80 is performed, individual package devices 87 each including a device chip 81 are manufactured.

[0150] In this way, even if there is substantially no difference in height between the area where the device chip 81 is provided on the workpiece 73 and the area outside of it, the method for manufacturing a package device according to this embodiment can suppress the occurrence of cracks in the device chip 81.

[0151] In the above-described method for manufacturing a package device, the molding resin 35, 69, 85 covering the workpiece 11, 21, 73 is thinned by grinding with grinding wheels 38c, 38d in resin thinning step S50. However, one aspect of the present invention is not limited to this. That is, in the method for manufacturing a package device according to one aspect of the present invention, the molding resin 35, 69, 85 may be thinned by a processing method other than grinding.

[0152] For example, instead of using grinding wheels 38c and 38d, molding resin 35, 69, and 85 may be thinned by cutting molding resin 35, 69, and 85 with a cutting tool (not shown) having a cutting blade at its lower end. The cutting tool is performed with a cutting tool cutting device (surface planer). In this case, in resin thinning step S50, workpiece 11, 21, and 73 are passed from the side below the cutting tool that rotates and moves on a circular orbit contained in a horizontal plane, and molding resin 35, 69, and 85 are cut by the cutting blade of the cutting tool.

[0153] At this time, the relative heights of the turning tool and the workpiece 11, 21, 73 are set in advance so that a predetermined amount of molding resin 35, 69, 85 is removed and a predetermined thickness remains on the workpiece 11, 21, 73. In this manner, in the manufacturing method for a package device according to one aspect of the present invention, the resin thinning step S50 can also be performed by turning a turning tool.

[0154] In addition, the structures, methods, etc. according to the above-described embodiments can be modified as appropriate without departing from the scope of the object of the present invention. [Explanation of symbols]

[0155] 11,21,73 Workpiece 11a,11b,21a,21b,23a,23b,25a,25b side 13, 13a, 13b Planned division line 15 areas 17a, 17c First Area 17b, 17d Second Area 19a Recess 19b Through hole 23 Circuit Board 25 Gap filling material 31,53,65,81 Device chips 33 Protrusion 33a,67 Terminal section 33b,61 Adhesive layer 35,69,85 Mold resin 37 Insulator layer 39 Resist film 41 Aperture 41a Through hole 43 Through electrode 45,57,75 wiring layer 47, 49, 59, 77 Conductor 51,83 Terminal section 55,71,87 packaged devices 73a,73b side 2 Grinding and polishing equipment 4 Foundation 4a aperture 4b, 4c Cassette stand 6,14,68 Transport unit 8,10 cassettes 12 Alignment mechanism 16 Turntable 18 Chuck table 18a Holding surface 20,40 Support structure 22 Z-axis movement mechanism 24 Z-axis guide rail 26 Z-axis moving plate 28 Z-axis ball screw 30 Z-axis pulse motor 32a, 32b Grinding unit 34,62 Housing 36,64,74 spindle 38a, 38b Grinding wheels 38c, 38d Grinding wheels 42 XZ axis movement mechanism 44 First guide rail 46 First moving plate 48 First ball screw 50 First pulse motor 52 Second guide rail 54 Second moving plate 56 Second ball screw 58 Second pulse motor 60 Polishing Unit 66 Polishing Pad 70 Cleaning Unit 72 Cutting unit 76 Cutting Blade 78 Non-contact thickness measuring instrument

Claims

1. A method of manufacturing a packaged device, comprising: a workpiece preparation step of preparing a workpiece having a first region on one surface of which a plurality of mutually intersecting planned division lines are set, the first region being partitioned by the planned division lines on the one surface and in which device chips are to be disposed in each of the sections, and a second region outside the first region; a device chip disposing step of disposing the device chip on the first region of the workpiece; a resin molding step of supplying a molding resin to the second region higher than the first region and the first region, after the workpiece preparing step and the device chip arranging step, to cover the device chip and the workpiece with the molding resin; a resin thinning step, performed after the resin molding step, of grinding the molding resin from the one surface side of the workpiece with a grinding wheel to a thickness such that the second region of the workpiece covered with the molding resin is not exposed and the device chip disposed in the first region is not exposed; a polishing step in which, after the resin thinning step, the molding resin is polished from the one surface side with a polishing pad to expose the second region of the workpiece, and the molding resin disposed in the first region and the second region are polished with the polishing pad to form a flat surface including the molding resin and the second region on the one surface side of the workpiece; a dividing step of dividing the workpiece along the dividing lines to produce individual packaged devices each including the device chip; Equipped with The method for manufacturing a packaged device is characterized in that the workpiece covered with the molding resin is not ground in the resin thinning step.

2. 2. The method for manufacturing a packaged device according to claim 1, wherein the first region of the workpiece is formed by a recess formed in the workpiece.

3. In the workpiece preparation step, a gap filling member having an opening is placed on a substrate to prepare the workpiece having, on one surface thereof, the first region located in the opening and the second region located outside the opening; 2. The method for manufacturing a package device according to claim 1, wherein the gap filling member is formed of a material whose volume expansion rate when temperature rises or pressure drops is smaller than that of the molding resin.

4. the gap filling member has the same planar shape as the planar shape of the substrate, 4. The method for manufacturing a package device according to claim 3, wherein the opening in the gap filling member is formed as a through-hole or a recess.

5. a measuring step of measuring a thickness of the workpiece covered with the molding resin before the resin thinning step in order to determine an amount of the molding resin to be removed in the resin thinning step; 5. The method for manufacturing a package device according to claim 1, wherein in the measuring step, the thickness of the workpiece in the second region is measured from the other surface opposite to the one surface using a non-contact thickness measuring device.

6. 6. The method for manufacturing a packaged device according to claim 1, wherein in the resin molding step, the second region of the workpiece covered with the molding resin is higher than the upper end of the device chip arranged in the first region.

7. A method of manufacturing a packaged device, comprising: a workpiece preparation step of preparing a workpiece having a plurality of mutually intersecting planned dividing lines set on one surface thereof; a device chip disposing step of disposing device chips on each of the areas partitioned by the planned dividing lines on the one surface of the workpiece; a resin molding step of supplying a molding resin to the one surface side of the workpiece to cover the device chip and the workpiece with the molding resin after the workpiece preparing step and the device chip arranging step; a resin thinning step, after the resin molding step, of grinding the molding resin from the one surface side of the workpiece with a grinding wheel to thin the molding resin to a thickness that does not expose the device chip; a polishing step in which, after the resin thinning step, the molding resin is polished from the one surface side of the workpiece with a polishing pad to expose the device chip, and the molding resin and the device chip are further polished with the polishing pad to form a flat surface including the molding resin and the device chip; a dividing step of dividing the workpiece along the dividing lines to produce individual packaged devices each including the device chip; Equipped with The method for manufacturing a packaged device is characterized in that the device chip and the workpiece covered with the molding resin are not ground in the resin thinning step.

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