Method of manufacturing a package

Abstract

Provided is a method for manufacturing a package that can reduce the likelihood of breakage of a device wafer. The method for manufacturing a package has the following steps: a device wafer preparation step (ST1) that prepares a device wafer; a groove formation step (ST2) that forms a groove reaching a depth of a finished thickness of a device chip from a front surface of the device wafer along a division predetermined line; a front surface sealing step (ST3) that seals the front surface of the device wafer with a sealing material and fills the groove with the sealing material; a back surface grinding step (ST5) that grinds a back surface of the device wafer corresponding to a device region to form a recess reaching the depth of the groove and forms an annular protrusion around the recess corresponding to a remaining region of an outer periphery; a back surface sealing step (ST7) that seals by filling the recess with a sealing material; and a division step (ST9) that forms a division groove that is narrower than the groove in width from the front surface of the device wafer along the groove, divides the device wafer to form a plurality of packages in which the device chips are sealed with the sealing material.

Description

TECHNICAL FIELD

[0001] The present application relates to a manufacturing method of a package that seals a device chip with a sealing material. BACKGROUND

[0002] For example, in a case where a metal film is formed as a heat sink on the back surface of a device chip, in order to easily perform the processing in the film forming step, a processing method is used in which only the back surface of the device wafer corresponding to the device region is thinned by grinding, and the outer peripheral portion is left as the original thickness (for example, refer to Patent Document 1).

[0003] Patent Document 1: Japanese Patent Application Publication No. 2007-19379

[0004] The device chips manufactured by the processing method shown in the above Patent Document 1 are respectively mounted on a mounting substrate. A sealing substrate in which a plurality of device chips are sealed and mounted is formed. Then, a package having a device chip is manufactured by dividing the sealing substrate.

[0005] In the processing method shown in Patent Document 1, for a device wafer in which a recess is formed in the center and an outer peripheral protrusion is formed, if the outer peripheral protrusion is removed, only the thinned central portion remains, and thus there is a possibility of breakage, and improvement is urgently desired. SUMMARY

[0006] The present application was completed in view of the above-described problems, and aims to provide a manufacturing method of a package that can reduce the possibility of breakage of a device wafer.

[0007] To solve the above problems and achieve the object, the manufacturing method of a package according to the present application is a manufacturing method of a package obtained by sealing a device chip with a sealing material, characterized by comprising the steps of: a device wafer preparation step of preparing a device wafer having a front surface having a device region in which a device is formed in each of regions divided by a plurality of division lines crossing each other and a peripheral remaining region surrounding the device region; a groove formation step of forming a groove reaching a depth of a finished thickness of a device chip from the front surface of the device wafer along the division lines; a front surface sealing step of sealing the front surface of the device wafer with a sealing material and filling the groove with the sealing material after the groove formation step is performed; a back surface grinding step of forming a recess reaching the depth of the groove by grinding a back surface of the device wafer corresponding to the device region and forming an annular protrusion corresponding to the peripheral remaining region surrounding the recess after the front surface sealing step is performed; a back surface sealing step of sealing by filling the recess with a sealing material after the back surface grinding step is performed; and a division step of forming a plurality of packages in which device chips are sealed with the sealing material by dividing the device wafer to form a division groove narrower than the groove from the front surface of the device wafer along the division groove after the back surface sealing step is performed.

[0008] In the above manufacturing method of a package, the device can have a protruding electrode, the front surface can be sealed with the sealing material so as to cover the protruding electrode in the front surface sealing step, and the manufacturing method of a package can further comprise a front surface planarization step of planarizing the sealing material of the front surface of the device wafer and exposing an end portion of the protruding electrode after the front surface sealing step is performed and before the back surface grinding step is performed.

[0009] In the above manufacturing method of a package, the manufacturing method of a package can further comprise a planarization step of planarizing the sealing material of the back surface of the device wafer after the back surface sealing step is performed and before the division step is performed.

[0010] The manufacturing method of a package according to the present application has an effect of being able to reduce the possibility of breakage of a device wafer. BRIEF DESCRIPTION OF DRAWINGS

[0011] Figure 1 is a plan view showing an example of a package manufactured by the manufacturing method of a package of Embodiment 1.

[0012] Figure 2 is a cross-sectional view along the line II-II in Figure 1 .

[0013] Figure 3 is a flowchart showing a flow of the manufacturing method of a package of Embodiment 1.

[0014] Figure 4 is a perspective view of a wafer prepared in a device wafer preparation step of a manufacturing method of the package shown in FIG. 1. Figure 3

[0015] Figure 5 is a plan view shown by enlarging a V portion in FIG. 2. Figure 4

[0016] Figure 6 is a perspective view of a groove formation step of a manufacturing method of the package shown in FIG. 3. Figure 3

[0017] Figure 7 is a sectional view of a device wafer after a front face sealing step of a manufacturing method of the package shown in FIG. 4. Figure 3

[0018] Figure 8 is a side view schematically shown by a partial section of a front face planarization step of a manufacturing method of the package shown in FIG. 5. Figure 3

[0019] Figure 9 is a sectional view of a device wafer after a front face planarization step of a manufacturing method of the package shown in FIG. 6. Figure 3

[0020] Figure 10 is a perspective view schematically showing a back face grinding step of a manufacturing method of the package shown in FIG. 7. Figure 3

[0021] Figure 11 is a sectional view of a device wafer after a back face grinding step of a manufacturing method of the package shown in FIG. 8. Figure 3

[0022] Figure 12 is a sectional view of a device wafer after a metal film formation step of a manufacturing method of the package shown in FIG. 9. Figure 3

[0023] Figure 13 is a sectional view of a device wafer after a back face sealing step of a manufacturing method of the package shown in FIG. 10. Figure 3

[0024] Figure 14 is a side view schematically shown by a partial section of a planarization step of a manufacturing method of the package shown in FIG. 11. Figure 3

[0025] Figure 15 is a perspective view schematically showing a division step of a manufacturing method of the package shown in FIG. 12. Figure 3

[0026] ​​​​​​​​​​​​Figure 16 is a plan view shown by enlarging the XVI part in Figure 15 .

[0027] Figure 17 is a sectional view of a device wafer after a dividing step of a manufacturing method of the package shown in Figure 3 .

[0028] Explanation of Reference Numerals

[0029] 1: package; 2: device chip; 3: sealing material; 5: front surface; 6: device; 8: bump (protrusion electrode); 9: back surface; 11: front end (end portion); 12: finished thickness; 20: device wafer; 21: dividing predetermined line; 22: device region; 23: outer peripheral remaining region; 24: groove; 24-1: depth; 25: recessed portion; 26: annular protrusion portion; 27: dividing groove; 27-2: width; ST1: device wafer preparation step; ST2: groove forming step; ST3: front surface sealing step; ST4: front surface planarization step; ST5: back surface polishing step; ST7: back surface sealing step; ST8: planarization step; ST9: dividing step. DETAILED DESCRIPTION

[0030] Embodiments for carrying out the present application will be explained in detail with reference to the drawings. The present application is not limited by the contents described in the following embodiments. In addition, among the structural elements described below, there are included structural elements that are substantially identical to those that can be easily conceived by those skilled in the art. Furthermore, the structures described below can be appropriately combined. In addition, various omissions, substitutions, or alterations of the structures can be made within a range not deviating from the gist of the present application.

[0031] [Embodiment 1]

[0032] A manufacturing method of a package according to Embodiment 1 of the present application will be explained with reference to the drawings. Figure 1 is a plan view showing an example of a package manufactured by the manufacturing method of the package according to Embodiment 1. Figure 2 is a sectional view along the II-II line in Figure 1 . Figure 3 is a flowchart showing a flow of the manufacturing method of the package according to Embodiment 1.

[0033] The manufacturing method of the package according to Embodiment 1 is a method of manufacturing a package 1 shown in Figure 1 and Figure 2 . As shown in Figure 1 and Figure 2 , the package 1 manufactured by the manufacturing method of the package according to Embodiment 1 has a device chip 2 and a sealing material 3. As shown in Figure 2As shown, the device chip 2 has a substrate 4 and a device 6 formed on a front surface 5 of the substrate 4. In Embodiment 1, the device 6 is an integrated circuit such as an IC (Integrated Circuit) or an LSI (Large Scale Integration).

[0034] In addition, as shown in Figure 3 , the device 6 has a plurality of bumps 8 as protrusion electrodes for connection with a substrate or the like not shown on the front surface 7. The bumps 8 are composed of a metal having conductivity. The bumps 8 protrude from the front surface 7 of the device 6 and are formed in a spherical shape in Embodiment 1.

[0035] As shown in Figure 4 , a metal film 10 is formed on a back surface 9 on the back side of the front surface 5 of the substrate 4 of the device chip 2. In Embodiment 1, the metal film 10 is composed of a metal having conductivity and functions as a heat sink of the package 1.

[0036] The sealing material 3 is composed of a synthetic resin having insulating properties and covers the front surface 7 of the device 6 of the device chip 2, the side surface of the device chip 2, and the metal film 10, thereby sealing the front surface 7 (i.e., the front surface of the device chip 2), the side surface, and the back surface 9 of the device 6. In addition, the sealing material 3 exposes a front end 11, which is an end portion of the bump 8, away from the front surface 7 of the device 6. In Embodiment 1, the sealing material 3 seals all of the side surfaces. That is, the device chip 2 is sealed by the sealing material 3. In addition, in Embodiment 1, the sealing material 3 is composed of a thermosetting resin.

[0037] As shown in Figure 3 , the manufacturing method of the package of Embodiment 1 has a device wafer preparation step ST1, a groove formation step ST2, a front surface sealing step ST3, a front surface planarization step ST4, a back surface grinding step ST5, a metal film formation step ST6, a back surface sealing step ST7, a planarization step ST8, and a division step ST9.

[0038] (Device wafer preparation step)

[0039] Figure 5 is a perspective view of a wafer prepared in the device wafer preparation step of the manufacturing method of the package shown in Figure 4 Figure 4 is a plan view in which a V portion in Figure 4 is enlarged. The device wafer preparation step ST1 is a step of preparing the device wafer 20 shown in Figure 5

[0040] ​​The device wafer 20 is a circular plate-like semiconductor wafer or the like that takes silicon, sapphire, or gallium arsenide as a substrate 4. In addition, in the description of the device wafer 20, the same reference numerals are attached to portions common to the device chip 2 and are described. As shown in FIG. 1, the device wafer 20 has a front surface 5 that has a device region 22 in which the devices 6 are respectively formed in regions divided by a plurality of crosswise partitioning predetermined lines 21, and a peripheral remaining region 23 that surrounds the device region 22. The peripheral remaining region 23 is a region in which the devices 6 are not formed. As shown in FIG. 2, the planar shape of the device 6 is formed in a rectangular shape, and a plurality of bumps 8 are provided on the front surface 7. When the device wafer 20 is ready, the groove formation step ST2 is entered. Figure 6 Figure 3

[0041] (Groove Formation Step)

[0042] Figure 2 is a perspective view schematically showing the groove formation step of the manufacturing method of the package shown in FIG. 1. The groove formation step ST2 is a step of forming a groove 24 reaching a finished thickness 12 (shown in FIG. 2) of the device chip 2 to a depth 24-1 of the device wafer 20 from the front surface 5 side of the substrate 4 along the partitioning predetermined line 21. In addition, the finished thickness 12 of the device chip 2 is the thickness of the device chip 2 from the front end 11 of the bump 8 to the metal film 10. Figure 6 Figure 6 In the embodiment 1, in the groove formation step ST2, the back surface 9 side of the device wafer 20 is placed on the holding surface of the not-shown chuck table of the cutting apparatus 30 shown in FIG. 3, and the cutting apparatus 30 suction-holds the back surface 9 side of the device wafer 20 on the holding surface of the chuck table. In the groove formation step ST2, the cutting apparatus 30 performs photographing of the front surface 5 of the device wafer 20 by the not-shown photographing member, detects the partitioning predetermined line 21, and thereby performs alignment of the cutting tool 32 of the cutting unit 31 with the partitioning predetermined line 21.

[0043] In the groove formation step ST2, the cutting apparatus 30 relatively moves the chuck table and the cutting tool 32 along the partitioning predetermined line 21 while causing the cutting tool 32 to cut into the depth 24-1 corresponding to the finished thickness 12 from the front end 11 of the bump 8 to the center in the width direction of the partitioning predetermined line 21 from the front surface 5 side of the device wafer 20, as shown in FIG. 4. In the groove formation step ST2, the cutting apparatus 30 forms the groove 24 along the partitioning predetermined line 21 with the cutting tool 32. The groove 24 is a so-called half-cut groove that is formed from the front surface 5 of the substrate 4 of the device wafer 20 all the way to the center in the thickness direction of the substrate 4. In the groove formation step ST2, as shown in FIG. 5, the device wafer 20 is divided into the device chips 2 by the groove 24. Figure 7

[0044] Figure 7 Figure 7 ​​​​​​As shown, when the groove 24 is formed along all the predetermined dividing lines 21, the front sealing step ST3 is entered.

[0045] Furthermore, in Embodiment 1, the cutting tool 36 has a first thickness, and the groove 24 has a first width 24-2 equal to the first thickness. Figure 3 (As shown). Furthermore, in Embodiment 1, the depth 24-1 of the groove 24 from the front end 11 of the bump 8 to the bottom surface is deeper than the finished thickness 12. In Embodiment 1, the groove 24 is formed by cutting the cutting tool 36 into the predetermined dividing line 21. However, in this invention, the groove 24 having a first width 24-2 can also be formed by ablation processing along the predetermined dividing line 21 using a laser beam of a wavelength that is absorbent to the device wafer 20.

[0046] (Front-side sealing procedure)

[0047] Figure 7 yes Figure 8 The diagram shows a cross-sectional view of the device wafer after the front sealing step in the packaging manufacturing method. The front sealing step ST3 is a step in which the front 7 side of the device 6 of the device wafer 20 is sealed with sealing material 3 and the groove 24 is filled with sealing material 3 after the groove forming step ST2.

[0048] In the front sealing step ST3, a thermosetting resin constituting the sealing material 3 is provided to the front side 7 of the device 6 of the device wafer 20, covering the front side 7 with the thermosetting resin and filling the groove 24 with the thermosetting resin. In the front sealing step ST3, the thermosetting resin is heated to harden it, such as... Figure 3 As shown, the front surfaces 5 and 7 are sealed using sealing material 3, and the groove 24 is filled using sealing material 3. After sealing the front surfaces 5 and 7 with sealing material 3 and filling the groove 24 with sealing material 3, the front surface planarization step ST4 is performed. In addition, in Embodiment 1, in the front surface sealing step ST3, the front surface 7 side of the device 6 is sealed with sealing material 3 in a manner that covers the entire bump 8. However, in this invention, the front surfaces 5 and 7 sides of the device 6 of the device wafer 20 can also be sealed with sealing material 3 so that the front end 11 of the bump 8 is exposed from the front surface 13 of the sealing material 3.

[0049] (Front-side planarization step)

[0050] Figure 9 It is shown schematically using partial cross-sections. Figure 3 A side view of the planarization step in the manufacturing method of the package shown. Figure 8 yes Figure 8Cross-sectional view of the device wafer after the front planarization step of the manufacturing method of the package shown. The front planarization step ST4 is a step of planarizing the front surface 13 of the sealing material 3 on the front surface 7 side of the device 6 of the device wafer 20 and exposing the front end 11 of the bump 8 after the front sealing step ST3 is implemented and before the back grinding step ST5 is implemented.

[0051] In Embodiment 1, in the front planarization step ST4, Figure 8 The blade cutting device 40 shown attracts and holds the back surface 9 side of the device wafer 20 to the holding surface 42 of the chuck table 41. In the front planarization step ST4, the blade cutting device 40 positions the front end of the blade tool 44 of the blade wheel 43 on the front surface 13 of the sealing material 3 at the height of the front end 11 of the bump 8. In the front planarization step ST4, as shown in Figure 9 As shown, the blade cutting device 40 rotates the blade wheel 43 about the axis of rotation parallel to the vertical direction by the spindle 45 and moves the chuck table 41, for example, along the Figure 10 arrow in the horizontal direction in, makes the chuck table 41 pass through below the blade wheel 43, and cuts the entire front surface 13 of the sealing material 3 with the blade tool 44 of the blade wheel 43.

[0052] In the front planarization step ST4, as shown in Figure 3 The blade cutting device 40 cuts the sealing material 3 that seals the front surface 7 of the device 6 of the device wafer 20 to expose the front end 11 of the bump 8 from the front surface 13 of the sealing material 3. In the front planarization step ST4, when the sealing material 3 is cut to expose the bump 8 from the front surface 13 of the sealing material 3, the back grinding step ST5 is entered.

[0053] In addition, in Embodiment 1, in the front planarization step ST4, the front end 11 of the bump 8 is exposed on the front surface 13 of the sealing material 3 by cutting the front surface 13 of the sealing material 3 with the blade tool 44 of the blade cutting device 40, but in the present application, it is also possible that a grinding device rotates the chuck table that holds the back surface side of the device wafer 20 about the axis of rotation and makes the grinding abrasive of the grinding grinding wheel that rotates by the spindle abut against the front surface 13 of the sealing material 3 to grind the front surface 13 of the sealing material 3, thereby exposing the front end 11 of the bump 8 on the front surface 13 of the sealing material 3. In addition, in the present application, in the case where the sealing material 3 is sealed in the state where the front end 11 of the bump 8 is exposed from the front surface 13 in the front sealing step ST3, the front planarization step ST4 can also not be implemented.

[0054] (Back grinding step)

[0055] Figure 11is a schematic view showing Figure 3 is a perspective view of a back surface grinding step of the manufacturing method of the package shown. Figure 10 is Figure 10 is a sectional view of the device wafer after the back surface grinding step of the manufacturing method of the package shown. The back surface grinding step ST5 is a step of grinding the back surface 9 of the substrate 4 of the device wafer 20 corresponding to the device region 22 to form a recess 25 reaching the depth of the groove 24 and to form an annular protrusion 26 corresponding to the outer peripheral remaining region 23 around the recess 25 after the front surface sealing step ST3 is implemented.

[0056] In the back surface grinding step ST5, a circular plate-shaped protection member 50 as a protection member which is the same diameter as the device wafer 20 is attached to the front surface 13 of the sealing material 3 of the device wafer 20. Figure 10 is the protection tape 50 shown. In addition, in Embodiment 1, the protection tape 50 composed of synthetic resin is attached to the front surface 13 of the sealing material 3 of the device wafer 20, but in the present application, the protection member is not limited to the protection tape 50, and can be a member which is hard and circular plate-shaped and the same diameter as the device wafer 20.

[0057] In the back surface grinding step ST5, Figure 10 is a grinding device 60 shown. The front surface 13 side of the sealing material 3 of the device wafer 20 is suction-held to a holding surface 62 of a chuck table 61 of the grinding device 60 through the protection tape 50 in the back surface grinding step ST5. As shown in Figure 11 is shown, the grinding device 60 rotates a grinding wheel 64 around an axis of rotation parallel to the vertical direction by a spindle 63 and rotates the chuck table 61 around an axis of rotation parallel to the vertical direction, provides a grinding fluid from a not-shown grinding fluid nozzle, and brings a grinding tool 65 of the grinding wheel 64 into abutment with the portion of the back surface 9 corresponding to the device region 22 and approaches the chuck table 61 at a prescribed feed rate, and grinds the portion of the back surface 9 corresponding to the device region 22 with the grinding tool 65.

[0058] In the back surface grinding step ST5, as shown in Figure 12 and Figure 3As shown, the portion of the back surface 9 corresponding to the device region 22 is ground using the grinding tool 65, a recess 25 having a planar shape of a circle is formed on the back surface 9 side of the substrate 4 corresponding to the device region 22, and the portion of the back surface 9 corresponding to the outer peripheral remaining region 23 is not ground to maintain the thickness before grinding, a ring-shaped protrusion 26 having a planar shape of a ring is formed on the back surface 9 side of the substrate 4 corresponding to the outer peripheral remaining region 23. In the present application, the portion of the back surface 9 of the substrate 4 of the device wafer 20 corresponding to the device region 22 indicates the portion of the back surface 9 of the substrate 4 of the device wafer 20 overlapping the device region 22 in the thickness direction of the device wafer 20. In the present application, the portion of the back surface 9 of the substrate 4 of the device wafer 20 corresponding to the outer peripheral remaining region 23 indicates the portion of the back surface 9 of the substrate 4 of the device wafer 20 overlapping the outer peripheral remaining region 23 in the thickness direction of the device wafer 20.

[0059] In the back surface grinding step ST5, the portion of the back surface 9 of the substrate 4 of the device wafer 20 corresponding to the device region 22 is ground until the thickness of the recess 25 of the device wafer 20 becomes a prescribed thickness (in Embodiment 1, the thickness after subtracting the thickness of the metal film 10 from the finished thickness 12). When the portion of the back surface 9 of the substrate 4 of the device wafer 20 corresponding to the device region 22 is ground to the prescribed thickness, the metal film forming step ST6 is entered. In addition, in the back surface grinding step ST5, in the device wafer 20 ground to the thickness of the recess 25 of the device wafer 20 being the prescribed thickness, since the depth 24-1 of the groove 24 is deeper than the finished thickness 12, the sealing material 3 filled into the groove 24 is exposed on the back surface 9 side.

[0060] (Metal film forming step)

[0061] Figure 12 is Figure 13 Cross-sectional view of the device wafer after the metal film forming step of the manufacturing method of the package shown. The metal film forming step ST6 is a step of forming the metal film 10 on the bottom of the recess 25. In Embodiment 1, in the metal film forming step ST6, as shown in Figure 3 When the metal film 10 having the same thickness is formed on the entire bottom of the recess 25, the back surface sealing step ST7 is entered.

[0062] (Back surface sealing step)

[0063] Figure 13 is Figure 14 Cross-sectional view of the device wafer after the back surface sealing step of the manufacturing method of the package shown. The back surface sealing step ST7 is a step of filling the sealing material 3 into the recess 25 to perform sealing after the back surface grinding step ST5 is performed.

[0064] In the back-side sealing step ST7, a thermosetting resin constituting the sealing material 3 is provided into the recess 25 formed on the back side 9 of the device wafer 20, thereby filling the recess 25 with the thermosetting resin. In the back-side sealing step ST7, the thermosetting resin is heated to harden it, such as... Figure 3 As shown, the recess 25 is sealed by filling it with sealing material 3. After sealing the recess 25 with sealing material 3, the process proceeds to planarization step ST8. Furthermore, in Embodiment 1, the thermosetting resin used to seal the recess 25 in the back sealing step ST7 is the same thermosetting resin used to seal the front sealing sides 5 and 7 in the front sealing step ST3, but this is not a limitation of the present invention.

[0065] (flattening step)

[0066] Figure 14 It is shown schematically using partial cross-sections. Figure 14 The diagram shows a side view of the planarization step in the packaging manufacturing method. The planarization step ST8 is a step that planarizes the front side 14 of the sealing material 3 on the back side 9 of the substrate 4 of the device wafer 20 after the back sealing step ST7 and before the splitting step ST9.

[0067] In implementation 1, during the flattening step ST8, Figure 15 The grinding apparatus 70 shown draws and holds the front side 13 of the sealing material 3 of the device wafer 20 onto the holding surface 72 of the chuck stage 71 via the protective strip 50. In the planarization step ST8, as... Figure 3 As shown, the grinding wheel 74 for grinding is rotated about an axis parallel to the vertical direction by the spindle 73, and the chuck table 71 is rotated about an axis parallel to the vertical direction. While grinding fluid is supplied by the grinding fluid nozzle (not shown), the grinding tool 75 of the grinding wheel 74 comes into contact with the front surface 14 of the sealing material 3 that seals the recess 25 and approaches the chuck table 71 at a predetermined speed, and the front surface 14 of the sealing material 3 is ground by the grinding tool 75.

[0068] In planarization step ST8, the front surface 14 and annular protrusion 26 of the sealing material 3 within the recess 25 of the sealing device wafer 20 are ground to planarize it until the grinding wheel 74 approaches the predetermined feed rate to the chuck table 71. In this embodiment, in planarization step ST8, the grinding apparatus 70 performs planarization until the front surface 14 of the sealing material 3 is coplanar with the annular protrusion 26. When the grinding wheel 74 approaches the predetermined feed rate to the chuck table 71, the process proceeds to division step ST9. Furthermore, in embodiment 1, the front surface 14 of the sealing material 3 is ground to planarize it in planarization step ST8; however, in this invention, planarization can also be performed by cutting with the cutting tool 44 of the cutting tool device 40, similar to the front surface planarization step ST4. In this invention, in planarization step ST8, either the grinding apparatus 70 or the cutting tool device 40 can be used depending on the sealing material 3. For example, in the present invention, in the planarization step ST8, based on the compound of the sealing material 3, since wear increases when grinding is performed using the grinding device 70, it is preferable to use the blade cutting device 40 for cutting.

[0069] (Segmentation steps)

[0070] Figure 16 It is shown schematically. Figure 15 A perspective view of the segmentation steps of the packaging manufacturing method shown. Figure 17 It is Figure 3 The top view shown in the enlarged XVI section. Figure 15 yes Figure 15 The diagram shows a cross-sectional view of the device wafer after the partitioning step in the manufacturing method of the package. The partitioning step ST9 is a step in which, after performing the back sealing step ST7, a partitioning groove 27 with a width 27-2 narrower than the groove 24 is formed along the front side 13 of the sealing material 3 of the device wafer 20, thereby partitioning the device wafer 20 to form multiple packages 1.

[0071] In Embodiment 1, during the separation step ST9, the protective tape 50 is peeled off from the front 13 side of the sealing material 3 of the device wafer 20. In Embodiment 1, during the separation step ST9, a circular plate-shaped material with a diameter larger than that of the device wafer 20 is attached to the back 9 side of the substrate 4 of the device wafer 20. Figure 16 The dicing strip 51 is shown, and an annular frame 52 with an inner diameter larger than that of the device wafer 20 is installed on the outer periphery of the dicing strip 51.

[0072] In implementation method 1, in the segmentation step ST9, Figure 15The cutting device 80 shown attracts and holds the back surface 9 side of the device wafer 20 across the dicing tape 51 to a holding surface of a chuck table not shown. In the dividing step ST9, the cutting device 80 photographs the front surface 13 of the sealing material 3 that seals the front surface 7 of the device wafer 20 using a photographing member, as shown in Figure 17 As shown, the bump 8 exposed from the front surface 13 of the sealing material 3 is detected, and thus alignment is performed in which the cutting tool 82 of the cutting unit 81 is aligned with the groove 24. In addition, the second thickness of the cutting tool 82 used in the dividing step ST9 is thinner than the first thickness of the cutting tool 32 used in the groove forming step ST2.

[0073] In the dividing step ST9, the cutting device 80 relatively moves the chuck table and the cutting tool 82 along the groove 24 while Figures 7-9 As shown, the cutting tool 82 is cut into the sealing material 3 buried in the groove 24 from the front surface 5, 7 side of the device wafer 20 to the center in the width direction of the sealing material 3 across the dicing tape 51. In the dividing step ST9, the cutting device 80 forms the dividing groove 27 of the second width 27-2 in the sealing material 3 that seals the groove 24 using the cutting tool 82. In the dividing step ST9, as shown in Figures 11-14 As shown, when the dividing groove 27 is formed in the sealing material 3 that seals all of the grooves 24 to divide the device wafer 20 into individual packages 1, the manufacturing method of the package ends. In addition, Figure 17 、 ​ and ​ Only two bumps 8 of the device 6 of each device chip 2 are shown, and the other bumps 8 are omitted.

[0074] In Embodiment 1, since the second thickness of the cutting tool 82 is thinner than the first thickness, the dividing groove 27 has the second width 27-2 that is equal to the second thickness and narrower than the first width 24-2. In Embodiment 1, the dividing groove 27 is formed by cutting processing of the sealing material 3 buried in the groove 24 using the cutting tool 82, but in the present application, the dividing groove 27 can also be formed by ablation processing in which a laser beam having a wavelength that is absorbable by the sealing material 3 is irradiated along the groove 24. The packages 1 divided one by one are picked up from the dicing tape 51 by a pickup device not shown and are carried to a subsequent process.

[0075] In the manufacturing method of the package of Embodiment 1 described above, the groove 24 as a half-cut groove is formed in the front surface 5 of the substrate 4, and after the front surface 5, 7 side is sealed with the sealing material 3, only the portion of the back surface 9 of the substrate 4 of the device wafer 20 corresponding to the device region 22 is ground to be thinned, thereby forming the recess 25 in the center and the outer peripheral remaining region 23 is formed as the annular protrusion 26 of the thickness before the grinding. Also, in the manufacturing method of the package, after the recess 25 in the center of the back surface 9 of the substrate 4 corresponding to the device region 22 is filled with the thermosetting resin constituting the sealing material 3, the device wafer 20 is divided. Therefore, in the manufacturing method of the package, the annular protrusion 26 does not need to be removed in order to be held by the chuck table of the cutting device 80 for dividing the device wafer 20 into individual packages 1. As a result, the manufacturing method of the package can reduce the possibility of breakage of the device wafer 20. Also, in the manufacturing method of the package, the device wafer 20 is sealed with the sealing material 3 in the recess 25 to be divided into individual packages 1, and therefore mounting to the substrate and the dividing process of the sealed substrate are not needed.

[0076] In the manufacturing method of the package, in the front surface planarization step ST4, the front end 11 of the bump 8 is exposed from the front surface 13 of the sealing material 3, and therefore the package 1 after the division can be reliably mounted to a substrate or the like.

[0077] Also, in the manufacturing method of the package, in the planarization step ST8, the front surface 14 of the sealing material 3 sealed in the recess 25 is planarized, and therefore the package 1 of high precision dimensions can be obtained.

[0078] Also, in the manufacturing method of the package, in the front surface planarization step ST4, the front surface 13 of the sealing material 3 is planarized with the blade tool 44 of the blade cutting device 40 to expose the front end 11 of the bump 8, and therefore compared to the case where the front surface 13 of the sealing material 3 is planarized with a grinding tool or the like, the burr formed by elongation of the metal constituting the bump 8 can be suppressed.

[0079] Also, the present application is not limited to the above-described embodiments. That is, various modifications can be made within the scope of the gist of the present application to be implemented.

Claims

1. A manufacturing method of a package which is obtained by sealing a device chip with a sealing material, wherein the manufacturing method of the package has the following steps: a device wafer preparation step of preparing a device wafer which has a front surface having a device region in which a device having a protruding electrode is formed in each of regions divided by a plurality of division predetermined lines intersecting each other and a peripheral remaining region surrounding the device region; a groove forming step of forming a groove reaching a depth of a finished thickness of a device chip from the front surface of the device wafer along the division predetermined lines; a front surface sealing step of sealing the front surface of the device wafer with a sealing material and filling the groove with the sealing material after the groove forming step is implemented; a back surface grinding step of forming a recess reaching the depth of the groove by grinding a back surface of the device wafer corresponding to the device region and forming an annular protrusion corresponding to the peripheral remaining region surrounding the recess after the front surface sealing step is implemented; a metal film forming step of forming a metal film on a bottom of the recess; a back surface sealing step of sealing by filling the recess with a sealing material after the back surface grinding step and the metal film forming step are implemented; and a division step of forming a plurality of packages in which the device chip is sealed with the sealing material by dividing the device wafer to form the device chip after the back surface sealing step is implemented, the groove is formed in a width narrower than the groove from the front surface of the device wafer along the groove.

2. The manufacturing method of the package according to claim 1, wherein the device has a protruding electrode, the device wafer preparation step is a step of preparing the device wafer in which the protruding electrode is formed in each of the regions divided by the plurality of division predetermined lines intersecting each other, the front surface sealing step is a step of sealing with the sealing material in a manner of covering the protruding electrode, and the manufacturing method of the package further has a front surface planarization step of planarizing the sealing material of the front surface of the device wafer and exposing an end portion of the protruding electrode after the front surface sealing step is implemented and before the back surface grinding step is implemented.

3. The manufacturing method of the package according to claim 1 or 2, wherein the manufacturing method of the package further has a planarization step of planarizing the sealing material of the back surface of the device wafer after the back surface sealing step is implemented and before the division step is implemented. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​

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