METHOD FOR MANUFACTURING A MOLDED CHIP

Abstract

A method for producing a molded chip (1), comprising: a preparation step (ST1) comprising attaching component sides of a plurality of component chips (2) arranged in rows to a protective member (100) which is thermally insulating, thereby forming a chip group (14) of component chips (2); after the preparation step (ST1), a molding step (ST2) comprising supplying a molding resin (3) to back surfaces (7) of the component chips (2) and gaps (17) between the component chips (2), thereby forming a mold wafer (18) in which the back surfaces (7) and the side surfaces (8) of the component chips (2) are covered with a resin molding (3); and after the molding step (ST2), a mold wafer separating step (ST3) based on an image in which an end face (5) of the mold wafer (18) has been imaged, comprising separating the mold wafer (18) along the center of gaps (17) filled with the resin molding (3) into mold chips (1).

Description

BACKGROUND OF THE INVENTION FIELD OF THE INVENTION

[0001] The present invention relates to a method for manufacturing a mold chip. DESCRIPTION OF THE RELATED PRIOR ART

[0002] Technologies are known for covering semiconductor chips with resin molding to protect them from environmental changes. For example, these technologies include Ball Grid Arrays (BGAs) and Chip Size Packages (CSPs). Since a chip and a substrate to which the chip is attached are connected by wires in these technologies, the finished package is significantly larger than the chip itself. A package called a Wafer Level Chip Size Package (WL-CSP) has been developed as a solution to this problem. However, this package is not sufficiently covered because only one of the six surfaces of the chip is covered with resin molding.

[0003] In addition, a process has been developed to cover more chip areas. According to this process, grooves are formed on the front side of a wafer along streets or projected dividing lines, and the front side of the wafer and the grooves are covered or filled with a resin molding compound. The back side of the wafer is then ground, and the resin molding compound in the grooves is cut along its center to produce device chips each having five molded surfaces (see, for example, JP 2017-022280 A).

[0004] US 2017 / 0032981 A1 relates to a semiconductor device comprising a semiconductor wafer, wherein the semiconductor wafer includes a plurality of semiconductor chips. An insulating layer is formed over an active surface of the semiconductor chip. A trench is formed in a non-active region of the semiconductor wafer between the semiconductor chips. A carrier with an adhesive layer is provided. The semiconductor chips are arranged over the adhesive layer and the carrier simultaneously as a unit. A grindback process is performed to remove a portion of the semiconductor wafer and expose the trench. The adhesive layer holds the semiconductor chip in position during the grindback process. An encapsulant is applied over the semiconductor chip and into the trench. The carrier and the adhesive layer are removed. The encapsulated semiconductor chips are cleaned and singulated into individual semiconductor devices.

[0005] US 2010 / 0311223 A1 relates to a method for dicing a thin wafer containing a low-K material using plasma without chipping or cracking during sawing, without using an etching mask, and without performing a separate wafer coating process. The method includes detecting scribe lines on a front side of the wafer using an image recognition unit to obtain detection information. SUMMARY OF THE INVENTION

[0006] However, the technology disclosed in JP 2017-022280 A has the disadvantage that, after the device side surfaces of the device chips are formed, the bumps connected to the electrodes on the devices are covered with resin moldings, resulting in limitations of the electrical connections.

[0007] It is therefore an object of the present invention to provide a method for manufacturing a mold chip capable of securing electrical connections of a component therefrom.

[0008] According to one aspect of the present invention, there is provided a method for manufacturing a molded chip, which includes a preparation step of attaching component sides of a plurality of component chips arranged in rows to a protective member having thermal insulation, thereby forming a chip group from the component chips; following the preparation step, a molding step of supplying a molding resin to back surfaces of the component chips and gaps between the component chips, thereby forming a molded wafer in which the back surfaces and side surfaces of the component chips are covered with a resin molding; and following the molding step, a mold wafer separating step, based on an image in which an end surface of the molded wafer has been imaged, of separating the molded wafer into molded chips along the center of gaps filled with the resin molding.

[0009] Preferably, the preparation step includes a groove forming step of forming grooves in a wafer having a plurality of regions defined by a grid of projected parting lines on a front side of the wafer and a plurality of components respectively formed in the regions to a depth greater than a final thickness, a protective member attaching step of attaching the protective member to the front side of the wafer in which the grooves have been formed, and a grinding step of grinding a back side of the wafer to thereby expose the grooves on the wafer and separate the wafer into the component chips.

[0010] Preferably, the preparation step includes a thinning step of grinding a backside of a wafer having a plurality of regions defined by a grid of projected dividing lines on a front side of the wafer and a plurality of devices formed respectively in the regions to thereby thin the wafer to a final thickness, and a separating step of separating the thinned wafer along the projected dividing lines.

[0011] Preferably, the method further includes, after the preparation step and before the molding step, an expanding step of expanding the protective element in plane directions to thereby widen distances between the device chips.

[0012] Preferably, the wafer has a round outer peripheral side surface, the preparation step includes an edge trimming step of trimming the round portion on the side surface of the wafer along the outer peripheral edge, and during the molding step, a molding resin supplied to the back side of the wafer is pressed against the back side of the wafer in a mold.

[0013] Preferably, after the molding step, the method further includes a protective member peeling step of applying an adhesive tape to the back side of the mold wafer and peeling the protective member from the end face of the mold wafer, in which the mold wafer is separated from the end face of the mold wafer during the mold wafer separating step.

[0014] The method of manufacturing a mold chip in accordance with the present invention is advantageous because it ensures electrical connections of the components of the device chips.

[0015] The above and other objects, features and advantages of the present invention and the modes for carrying them out will best become apparent and the invention itself will be best understood by studying the following description and appended claims with reference to the attached drawings which show preferred embodiments of the invention. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a perspective view illustrating, by way of example, a mold chip manufactured by a method for manufacturing a mold chip in accordance with a first embodiment of the present invention; Fig. 2 is a perspective view illustrating, as an example, a wafer from which the Fig. 1 illustrated mold chip is manufactured; Fig. 3 is an enlarged sectional view taken along line III-III of the Fig. 2; Fig. 4 is a flowchart illustrating the procedure of the method for manufacturing a mold chip according to the first embodiment; Fig. 5 is a schematic side view showing an edge trimming step of a preparation step of the method for manufacturing a mold chip shown in Fig. 4 is illustrated, illustrates; Fig. 6 is a schematic side view showing a groove forming step of the preparation step of the Fig. 4 illustrates the method for manufacturing a mold chip; Fig. Fig. 7 is a schematic sectional view of a wafer after a protective element attachment step of the preparation step of the wafer shown in Fig. 4 illustrates a method for manufacturing a mold chip; Fig. Fig. 8 is a schematic, partially sectional side view showing a grinding step of the preparation step of the Fig. 4 illustrates the method for manufacturing a mold chip; Fig. 9 is a schematic side view showing a molding step of the Fig. 4 illustrates the method for manufacturing a mold chip; Fig. 10 is a schematic sectional view showing a mold wafer separating step of the Fig. 4 illustrates the method for manufacturing a mold chip; Fig. 11 is a flowchart illustrating the procedure of a method for manufacturing a mold chip in accordance with a second embodiment of the present invention; Fig. 12 is a schematic, partially sectional side view showing a dilution step of a preparation step of the Fig. 11 illustrates the method for manufacturing a mold chip; Fig. 13 is a schematic, partially sectional side view showing a separating step of the preparation step of the Fig. 11 illustrates the method for manufacturing a mold chip; Fig. 14 is a flowchart illustrating the procedure of a method for manufacturing a mold chip according to a first modification of the first and second embodiments; Fig. Figure 15 is a schematic sectional view illustrating the manner in which a plurality of individual, separate component chips are assembled during an expanding step of the device shown in Fig. 14 illustrated method for producing a molded chip are held on an expanding device; Fig. Figure 16 is a schematic sectional view illustrating the manner in which a Fig. 15 illustrated protective element is expanded; Fig. Fig. 17 is a schematic sectional view illustrating the manner in which the distance between the component chips is adjusted on the Fig. 16 illustrated protective element and an annular frame; Fig. 18 is a flowchart illustrating the procedure of a method for manufacturing a mold chip according to a second modification of the first and second embodiments; Fig. 19 is a schematic sectional view showing a mold wafer, etc. after a protective member peeling step of the device shown in Fig. 18 illustrates the method for manufacturing a mold chip; Fig. 20 is a schematic, partially sectional side view showing a mold wafer separating step of the Fig. 18 illustrates the method for manufacturing a mold chip; Fig. 21 is a schematic, partially sectional side view illustrating a grinding step of a method for manufacturing a mold chip in accordance with a third modification of the first embodiment; Fig. 22 is a schematic sectional view illustrating a molding step of the method for manufacturing a molded chip in accordance with the third modification of the first embodiment; and Fig. 23 is a schematic, partially sectional side view illustrating a thinning step of a method for manufacturing a mold chip in accordance with a third modification of the second embodiment. [First embodiment]

[0016] A method of manufacturing a mold chip in accordance with a first embodiment of the present invention will be described below with reference to the drawings. Fig. 1 is a perspective view illustrating, by way of example, a mold chip manufactured by the method for manufacturing a mold chip according to the first embodiment. Fig. 2 is a perspective view illustrating, by way of example, a wafer from which the Fig. 1 illustrated mold chip is manufactured. Fig. 3 is an enlarged sectional view taken along line III-III of the Fig. 2.

[0017] As in Fig. 1, a mold chip 1 according to the first embodiment includes a component chip 2 and a resin mold 3. As shown in Fig. 2, the device chip 2 includes a substrate 4 and a device 6 formed on a front side 5 of the substrate 4. The device 6 has a surface that constitutes a device side. Therefore, the device chip 2 includes the device side on the front side 5 of the substrate 4. The device 6 is an electronic component, such as an integrated circuit (IC), a large-scale integration circuit (LSI circuit), or the like. The device chip 2 also includes a plurality of at least electrodes or electrode bumps, not illustrated, arranged on the device side for connecting the device side to an unillustrated substrate or other chip.

[0018] The resin molding 3 is made of an insulating synthetic resin and covers a back surface 7 of the substrate 4, which is opposite the end surface 5 on which the component 6 is arranged, and side surfaces 8 that adjoin the end surface 5 and the back surface 7. According to the present embodiment, the resin molding 3 covers all side surfaces 8.

[0019] The mold chip 1 of the structure described above is produced by separating a Fig. 2 into component chips 2 and covering the back surface 7 and the side surfaces 8 of each of the component chips 2 with the resin molding 3. The wafer 10 to be separated into the component chips 2 may be a semiconductor wafer or an optical component wafer in the form of a circular plate, with the substrate 4 made of silicon, sapphire, gallium arsenide, or the like. The wafer 10 is described using the same reference numerals for components that the component chip 2 has in common. As shown in Fig. 2, the wafer 10 has components 6 which are formed respectively in a plurality of regions which are delimited from one another by a grid of projected separating lines 11 on the end face 5 of the substrate 4.

[0020] In addition, the wafer 10, as shown in Fig. 3, a round outer peripheral side surface 12 protrudes radially outward. The outer peripheral side surface 12 of the wafer 10 has a round cross-sectional shape in which the center protrudes maximally in a radially outward direction in the thickness direction of the wafer 10. In other words, the wafer 10 has a round portion 13 extending entirely around an outer peripheral edge thereof.

[0021] The process for producing the Fig. 1 illustrated mold chips 1 is described below. Fig. 4 is a flowchart illustrating the procedure of the method for manufacturing a mold chip according to the first embodiment.

[0022] In accordance with the method for manufacturing a molded chip, the molded chip 1 is manufactured by separating the wafer 10 into individual component chips 2 along the projected separation lines 11 and covering the back surface 7 and the side surfaces 8 of each of the component chips 2 with the resin molding 3. As shown in Fig. 4, the method for manufacturing a mold chip includes a preparation step ST1, a molding step ST2, and a mold wafer separating step ST3. (Preparation step)

[0023] Fig. 5 is a schematic side view showing an edge trimming step of the preparation step ST1 of the Fig. 4 illustrates the method for manufacturing a mold chip. Fig. 6 is a schematic side view showing a groove forming step of a preparation step ST1 of the Fig. 4 illustrates the method for manufacturing a mold chip. Fig. Fig. 7 is a schematic sectional view of a wafer after a protective element attachment step of a preparation step ST1 of the wafer shown in Fig. 4 illustrates a method for manufacturing a mold chip. Fig. Fig. 8 is a schematic, partially sectional side view showing a grinding step of a preparation step ST1 of the Fig. 4 illustrates the method for manufacturing a mold chip.

[0024] A preparation step ST1 is a step in which the component sides of a plurality of row-arranged component chips 2 are attached to a thermally insulating protection element 100 (see Fig. 9), which produces a chip group 14 comprising the row-arranged component chips 2. In accordance with the first embodiment, the preparation step ST1, as shown in Fig. 4, an edge trimming step ST11, a groove forming step ST12, a protective member attaching step ST13, and a grinding step ST14. (Edge trimming step)

[0025] An edge trimming step ST11 is a step in which the round portion 13 on the end face 5 of the wafer 10 is removed along the outer peripheral edge of the wafer 10. In accordance with the first embodiment, a cutting device 20 (see Fig. 5) in the edge trimming step ST11, the back side 7 of the wafer 10 is clamped to a holding surface 22 of a clamping table 21 via a negative pressure.

[0026] In the edge trimming step ST11, the cutting device 20 holds the back side 7 of the wafer 10 on the holding surface 22 of the chuck table 21 via a negative pressure, and moves a cutting blade 25 which is rotated by a spindle 24 of a cutting unit 23, as shown in Fig. 5 illustrates, during rotation of the chuck table 21 about an axis parallel to the vertical directions, to cut into the round portion 13 at the outer peripheral edge of the wafer 10 from its end face 5 to a depth which exceeds a Fig. 1, thereby removing the round portion 13 on the end face 5. When the round portion 13 has been removed from the end face 5 along the entire outer peripheral edge of the wafer 10 during the trimming step ST11, the process proceeds from the edge trimming step ST11 to the groove forming step S12. The final thickness 15 is the same as the thickness of the wafer 10 that was thinned during the grinding step ST14. (Groove formation step)

[0027] The groove forming step ST12 is a step in which grooves 16 having a depth greater than the final thickness 15 are formed in the end face 5 of the wafer 10 along the projected separation lines 11 on the end face 5. In the groove forming step ST12, a cutting device 30 (see Fig. 6) the back side 7 of the wafer 10 via a negative pressure on a holding surface 32 of a chuck table 31. An unillustrated image recording unit records an image of the front side 5 of the wafer 10 and an alignment process is carried out to position a cutting blade 35 of a cutting unit 33 in alignment with one of the projected separation lines 11 on the wafer 10 based on the recorded image.

[0028] In the groove forming step ST12, the cutting device 30 moves the wafer 10 and the cutting blade 35 along the projected separation line 11 based on the result of the alignment process, as shown in Fig. 6 illustrates, while moving the cutting blade 35 relative to each other to cut from the end face 5 along the projected dividing line 11 to a depth greater than the final thickness 15, thereby forming a groove 16 in the wafer 10 to a depth greater than the final thickness 15. In the groove forming step ST12, the cutting device 30 forms grooves 16 along all the projected dividing lines 11. Thereafter, the process proceeds from the groove forming step ST12 to the protective member attaching step ST13. (Protective element attachment step)

[0029] The protective element attaching step ST13 is a step in which a protective element 100 (see Fig. 7) is applied as a wafer protection member to the end face 5 of the wafer 10 having the grooves 16 formed therein. According to the first embodiment, a protective tape is used as the protective member 100. The protective tape has a circular shape whose diameter is larger than that of the wafer 10 and is thermally insulating. The term "thermally insulating" used herein means that the properties of the protective member 100 remain unchanged even when heated to a temperature reached when the back surface 7 and the end face 8 of each of the device chips 2 are covered with a molding resin 3 during the molding step ST2.

[0030] In the protective member attaching step ST13, a known holder in accordance with the first embodiment holds the wafer 10 and an annular frame 101 (see Fig. 7) via a negative pressure on a holding surface of a clamping table (not shown), after which the protective element 100, as shown in Fig. 7, is attached to the end face 5 of the wafer 10 and the annular frame 101. After the protective member attachment step ST13, the wafer 10 is supported by the protective member 100 in the opening of the annular frame 101. When the protective member 100 has been attached to the end face 5 of the wafer 10 and the annular frame 101 during the protective member attachment step ST13, the process proceeds from the protective member attachment step ST13 to the grinding step ST14. (grinding step)

[0031] The grinding step ST14 is a step in which the back side 7 of the wafer 10 is ground until the grooves 16 on the back side 7 are exposed, which separates the wafer 10 into component chips 2. In the grinding step ST14, a grinding device 40 (see Fig. 8) In accordance with the present embodiment, the end face 5 of the wafer 10 is inserted via a vacuum onto a holding surface 42 of a chuck table 41 with the protective element 100 therebetween, and holds the annular frame 101 in position with clamping elements 43. In the grinding step ST14, the grinding device 40 rotates as shown in Fig. 8 illustrates the chuck table 41 about its own axis, and presses grinding stones 47 of a grinding unit 46 rotating about its own axis against the back side 7 of the wafer 10 while supplying a grinding fluid 45 from a grinding fluid nozzle 44 to the back side 7 of the wafer 10.

[0032] During the grinding step ST14, the grinding device 40 grinds the wafer 10 from the back side 7 to thin the wafer 10 to the final thickness 15. Since the grooves 16 have been formed deeper than the final thickness 15 in the wafer 10 during the grinding step ST14 from the front side 5, the grooves 16 are exposed at the back side 7 when the grinding device 40 thins the wafer to the final thickness 15, which separates the wafer 10 into individual device chips 2. At this time, gaps 17 (see Fig. 9), which are as wide as the grooves 16, are formed between adjacent component chips 2. In this way, a chip group 14 is produced, which includes the component chips 2 with the protective element 100 attached to their component sides. When the wafer 10 has been thinned to the final thickness 15 during the grinding step ST14, the process proceeds from the preparation step ST1 to the forming step ST2. (Forming step)

[0033] Fig. 9 is a schematic side view showing a molding step of the Fig. 4. The molding step ST2 is a step in which, after the preparation step ST1, a molding resin 3 in a molten phase is supplied to the gaps between the back surfaces 7 of the component chips 2, a mold 53, and also to the gaps 17 between the component chips 2 to cover the back surfaces 7 and the side surfaces 8 of the component chips 2 with a resin mold 3, thereby forming a mold wafer 18. The mold wafer 18 is thicker than the wafer 10, which has been thinned to the final thickness 15 during the grinding step ST14, and has a circular shape with a larger diameter than the wafer 10.

[0034] During the forming step ST2, the protective element 100 is formed as shown in Fig. 9, in accordance with the first embodiment, the protective member 100 is held on a flat support surface 52 of a table 51 by a molding machine 50, and all the component chips 2 attached to the protective member 100 are covered with a mold 53 to primary form a molded product. The mold 53 has a hollow cylindrical cavity 54 defined therein by wall surfaces spaced from the component chips 2 attached to the protective member 100 and having a shape complementary to the mold wafer 18.

[0035] In the molding step ST2, a hopper (not shown) of the molding machine 50 is loaded with pellets of the molding resin 3. Then, the molding machine 50 heats the pellets of the molding resin 3 in a heating cylinder, thereby melting the pellets. After mixing in the heating cylinder, the molding resin 3 is introduced in a molten state into the cavity 54 in the mold 53 to fill the cavity 54. In the molding step ST2, the molding resin 3, which is forced into the cavity 4 and supplied to the back surface 7 of the wafer 10, is pressed by the molding machine 50 against the back surfaces 7 of the component chips 2 to cover the back surfaces 7 and the side surfaces 8, and is then cured into a resin mold 3. When the mold resin 3 in the cavity 54 has been cured into the mold resin during the molding step ST2, the process proceeds from the molding step ST2 to the mold wafer separating step ST3.In the molding step ST2, a chip group of row-arranged component chips 2 may be immersed in a molding resin in a molten phase to form a resin molding layer 3 on the component chips 2, or a chip group of row-arranged component chips 2 may be laminated by a film of molding resin to form a resin molding layer 3 on the component chips 2. (Shaped wafer separation step)

[0036] Fig. 10 is a schematic sectional view showing a mold wafer separating step of the Fig. 4 illustrates the method for manufacturing a molded chip. The molded wafer separation step ST3 is a step in which, after the molding step ST2, the molded wafer 18 is separated into molded chips along the center of the gaps 17 filled with the resin molding 3 based on a captured image of the end face 5 of the molded wafer 18.

[0037] In the shaped wafer separation step ST3, a cutting device 60 places a central portion of the protective member 100 attached to the end faces 5 of the device chips 2 on a circular light-transmitting plate 62 of a chuck table 61 made of a light-transmitting material such as glass or the like, and places an outer edge of the protective member 100 attached to the annular frame 101 on an annular frame 66 of the chuck table 61, the annular frame 66 being made of stainless steel or the like. In the shaped wafer separation step ST3, the cutting device 60 holds the outer edge of the protective member 100 to the frame 66 via suction forces applied to the outer edge of the protective member 100 through a suction opening 67 defined in the frame 66.An imaging unit 68, which is arranged below the light-transmitting plate 62, takes an image of the end faces 5 of the component chips 2 of the mold wafer 18 through the light-transmitting plate 62.

[0038] In the shaped wafer separation step ST3, the cutting device 60 performs an alignment operation to position a cutting blade 65 of a cutting unit 63 based on the captured image of the end faces 5 of the component chips 2 in the transverse direction aligned with the center of a row of columns 17 along one of the projected separation lines 11. Then, the cutting device 60 moves, as shown in Fig. 10 illustrates the mold wafer 18 and the cutting blade 65 being aligned based on the result of the alignment process along the projected dividing line 11 while moving the cutting blade 65 relative to each other to cut into the mold wafer 18 at the center of the row of columns 17 from the resin mold 3 side, that is, the back side 7, until the cutting blade 65 reaches the protective member 100, thereby separating the mold wafer 18 into mold chips 1. The mold wafer separating step ST3 ends when the cutting device 60 moves the cutting blade 65 to cut into the mold wafer 18 at the respective centers of the rows of columns 17 along all the projected dividing lines 11, separating the mold wafer 18 into mold chips 1. The individual separated mold chips 1 are picked up from the protective member 100 by a known picking device. The cutting blade 65 used in the shaped wafer separation step ST3 is thinner than the width of each of the columns 17.

[0039] The method for manufacturing a molded chip according to the first embodiment includes a groove forming step ST12 for forming the grooves 16 in the end surface 5 of the wafer 10 to a depth greater than the final thickness 15, a protective member attaching step ST13 for attaching the protective member 100 to the end surface 5 of the wafer 10, and a grinding step ST14 for thinning the wafer 10 from the back surface 7 to the final thickness 15, thereby separating the wafer 10 into the individual component chips 2 while they are attached to the protective member 100. The method for manufacturing a molded chip further includes a molding step ST2 for covering the back surfaces 7 and the side surfaces 8 of the component chips 2 on the protective member 100 with the resin molding 3.

[0040] Therefore, the method for manufacturing a molded chip allows the back surfaces 7 and the side surfaces 8 of the component chips 2 to be covered with the resin molding 3 while the components 6 are held in their relative positions on the wafer 10. As a result, the method for manufacturing the molded chip 1 is advantageous because electrodes and electrode bumps on the component sides are protected from being contaminated by the resin molding 3 and electrical connections of the components 6 are secured.

[0041] Furthermore, the preparation step ST1 in the method for manufacturing a mold chip includes an edge trimming step ST11 for removing the round portion 13 on the end surface 5 of the wafer 10. Consequently, after the grinding step ST14, the wafer 10 is free from an outer peripheral cutting edge that would otherwise remain unremoved outside the component chips 2 in an outermost peripheral region if the round portion 13 were thinned. The method for manufacturing a mold chip according to the first embodiment is thus capable of preventing the component chips 2 from being chamfered by an outer peripheral cutting edge near the outer peripheral edge of the wafer 10 when the mold resin 3 is pressed against the back surface 7 of the wafer 10 in a molten state during filling of the cavity 54.As a result, the method of manufacturing a mold chip according to the first embodiment prevents them from being displaced in position or otherwise adversely affected when the device chips 2 are covered with the mold resin 3 in the molten state.

[0042] In the method for manufacturing a mold chip according to the first embodiment, since the cutting blade 35 cuts the wafer 10 from the back side 7 during the groove forming step ST12 and the cutting blade 65 cuts the mold wafer 18 from the resin mold 3 side during the mold wafer separating step ST3, debris or chips generated in the groove forming step ST12 and the mold wafer separating step ST3 are prevented from being deposited on the device sides. Moreover, the mold wafer separating step ST3 according to the present invention can be performed by an ablation process or a modified layer forming process in which a laser beam having a wavelength that can be absorbed or transmitted by the resin mold 3 is applied to the resin mold 3. [Second embodiment]

[0043] Hereinafter, a method of manufacturing a mold chip in accordance with a second embodiment of the present invention will be described with reference to the drawings. Fig. 11 is a flowchart illustrating the procedure of the method for manufacturing a mold chip according to the second embodiment. Fig. Fig. 12 is a schematic, partially sectional side view showing a thinning step of a preparation step of the method for manufacturing a mold chip shown in Fig. 11 is illustrated. Fig. 13 is a schematic, partially sectional side view showing a separating step of the preparation step of the Fig. 11 illustrates the method for manufacturing a mold chip. In the Fig. 11 to 13, those parts which are identical to those in accordance with the first embodiment are designated by like reference numerals and will not be described in detail below.

[0044] The method for manufacturing a mold chip in accordance with the second embodiment is a method for manufacturing a component chip 1 as in the first embodiment. As shown in Fig. 11, the method for manufacturing a mold chip according to the second embodiment includes a preparation step ST1-2, a molding step ST2, and a mold wafer separating step ST3, and the preparation step ST1-2 includes an edge trimming step ST11, a thinning step ST15, and a separating step ST16. (dilution step)

[0045] The thinning step ST15 is a step in which the back surface 7 of the wafer 10 is ground to thin the wafer 10 to a final thickness 15. According to the second embodiment, in the thinning step ST15, after the edge trimming step ST11, the protective member 100 is attached to the end surface 5 of the wafer 10, and the annular frame 101 is attached to the outer edge of the protective member 100. In the thinning step ST15, a grinding device 70 (see Fig. 12) the end face 5 of the wafer 10 after the edge trimming step ST11 is clamped to a holding surface 72 of a clamping table 71 by means of a vacuum with the protective element 100 inserted therebetween and holds the annular frame 101 in position with clamping elements 73. As shown in Fig. 12, in the thinning step ST15, the grinding device 70 rotates the chuck table 71 about its own axis and presses grinding stones 77 of a grinding unit 76 rotating about its own axis against the back surface 7 of the wafer 10 while supplying a grinding fluid 75 to the back surface 7 of the wafer 10 from a grinding fluid nozzle 74.

[0046] In the thinning step ST15, the grinding device 70 grinds the wafer 10 from the back side 7 to thin the wafer 10 to a final thickness 15. Since the round portion 13 of the wafer 10 has been removed from the end side 5 to a depth greater than the final thickness 15 in the edge trimming step ST11, the round portion 13 is completely removed when the grinding device 70 thins the wafer 10 to the final thickness 15. When the wafer 10 has been thinned to the final thickness 15 in the thinning step ST15, the process proceeds from the thinning step ST15 to the separating step ST16. (separation step)

[0047] The separation step ST16 is a step in which the thinned wafer 10 is separated along the projected separation lines 11. In the separation step ST16, a cutting device 80 (see Fig. 13) the end face 5 of the wafer 10 is inserted via a vacuum onto a holding surface 82 of a clamping table 81 with the protective element 100 in between and clamps the annular frame 101 in its position with clamping elements 84. In the separation step ST16, the cutting device 80, as shown in Fig. 13 illustrates, with an infrared camera 86, captures an image of the back side 7 of the wafer 10, detects one of the projected separation lines 11 and, based on the captured image, performs an alignment process to position a cutting blade 85 of a cutting unit 83 in alignment with the projected separation line 11 on the wafer 10.

[0048] As in Fig. 13, during the separation step ST16, the cutting device 80 moves the wafer 10 and the cutting blade 85 based on the result of the alignment process along the projected separation line 11 while moving the cutting blade 85 relative to each other to cut into the wafer 10 from the back side 7 along the projected separation line 11, thereby separating the wafer 10 into individual device chips 2. When the cutting device 80 has moved the cutting blade 85 to cut along all the projected separation lines 11 in the wafer 10 during the separation step ST16, separate the wafer 10 into individual device chips 2, and form gaps 70 between the device chips 2, the preparation step ST1 ends. The method then proceeds from the preparation step ST1 to the forming step ST2.

[0049] The method for manufacturing a component chip according to the second embodiment includes a thinning step ST15 for attaching the protective member 100 to the end face 5 of the wafer and thinning the wafer 10 to the final thickness 15, and the separating step ST16 for separating the wafer 10 into individual component chips 2, thereby separating the wafer 10 into the individual component chips 2 while being attached to the protective member 100. As a result, the mold chip manufacturing method enables the back surfaces 7 and the side surfaces 8 of the component chips 2 to be covered with the resin molding 3 while holding the components 6 in position relative to each other on the wafer 10. The mold chip manufacturing method is advantageous because electrodes and electrode bumps on the component sides are prevented from being contaminated by the resin molding 3 and electrical connections of the components 6 are secured.

[0050] In the method for manufacturing a molded chip according to the first embodiment, the preparation step ST1 further includes an edge trimming step ST11 for removing the round portion 13 on the end face 5 of the wafer 10. Accordingly, after the grinding step ST14, the wafer 10 is free of an outer peripheral cutting edge that would otherwise remain unremoved outside the device chips 2 at an outermost peripheral region if the round portion 13 were thinned. The method for manufacturing a molded chip according to the second embodiment is thus capable of preventing the device chips 2 from being displaced in position or otherwise adversely affected when the device chips 2 are covered with the mold resin 3 in the molten state.

[0051] On the other hand, in the method for manufacturing a mold chip according to the second embodiment, since the cutting blade 85 cuts into the wafer 10 from the back side 7 in the separating step ST16 and the cutting blade 65 cuts into the mold wafer 18 from the resin molding 3 side in the mold wafer separating step ST3, debris or chips are prevented from being deposited on the device sides. [First variation]

[0052] A method of manufacturing a mold chip in accordance with a first modification of the first and second embodiments of the present invention will be described below with reference to the drawings.

[0053] Fig. 14 is a flowchart illustrating the procedure of a method for manufacturing a mold chip according to a first modification of the first and second embodiments. Fig. 15 is a schematic sectional view illustrating the manner in which a plurality of individual separated component chips are assembled in an expanding step of the device shown in Fig. 14 illustrated method for producing a molded chip on an expanding device. Fig. Figure 16 is a schematic sectional view illustrating the manner in which a Fig. 15 illustrated protective element is expanded or stretched. Fig. Figure 17 is a schematic sectional view illustrating the manner in which the distance between the Fig. 16 illustrated component chips on the protective element and an annular frame. In the Fig. 15 to 17, those parts which are identical to those in accordance with the first and second embodiments are designated by identical reference numerals and will not be described in detail below.

[0054] As in Fig. As illustrated in Figure 14, the method for manufacturing a molded chip according to the first modification is the same as the method for manufacturing a molded chip according to the first embodiment or the second embodiment, except that the protective member 100 is expandable and the method includes the expanding step ST20. The expanding step ST20 is a step of expanding the protective member 100 in planar directions to increase the distances between the device chips 2.

[0055] In the expanding step ST20, an expanding device 90 (see Fig. 9) by clamping the annular frame 101 with the clamping elements 91, a plurality of component chips 2 attached or adhered to the protective element 100 with the back sides 7 of the component chips 2 facing upwards. At this time, the expanding device 90, as shown in Fig. 15, the protective member 100 is flattened by placing a hollow, cylindrical expanding drum 92 against a portion of the protective member 100 located between the wafer 10 and the annular frame 101. The expanding drum 92 has an inner diameter and an outer diameter that are smaller than the inner diameter of the annular frame 101 and larger than the outer diameter of the wafer 10, respectively, and is disposed at a position coaxial with the annular frame 101 fixed by the clamping members 91.

[0056] In accordance with the first modification, the expanding device 90 lifts the expanding drum 92 as shown in Fig. 16, during the expansion step ST20. Since the protective element 100 rests against the expansion drum 92, the protective element 100 is expanded in plane directions, and radial tensile forces act on the protective element 100 as a result of its elongation.

[0057] When the radial tensile forces act on the protection member 100, the distance between adjacent ones of the component chips 2 is widened, insofar as the wafer 10 has been separated into the individual component chips 2. According to the first modification, the expanding drum 92 is raised to expand the protection member 100 in the expanding step ST20. However, the present invention is not limited to such an expanding manner. Instead, the clamping members 91 may be lowered. In other words, the expanding drum 92 may be raised relative to the clamping members 91, or the clamping members 91 may be lowered relative to the expanding drum 92.

[0058] In accordance with the first modification, the expanding device 90 then lowers the expanding drum 92 during the expanding step ST20 and heats and shrinks the slackened portion of the protective member 100 that has been generated as a result of the expansion of the protective member 100 between the wafer 10 and the annular frame 101, as shown in Fig. 17, with a heating unit 93. In the expanding step ST20, the expanding device 90 heats and shrinks the slackened portion of the protective member 100 created between the wafer 10 and the annular frame 101, maintaining the distance between the adjacent ones of the device chips 2 at the time the protective member 100 is expanded. The expanding step ST20 ends when the expanding device 90 has heated and shrunk the slackened portion of the protective member 100 between the wafer 10 and the annular frame 101. Then, the process proceeds from the expanding step ST20 to the forming step ST2. In accordance with the present invention, for example, instead of heating the protective member 100, the slackened portion may be removed or eliminated by reattaching the protective member 100 to a frame with a smaller diameter.

[0059] In the method for manufacturing a molded chip according to the first modification, since the distance between adjacent ones of the component chips 2 is made wider by expanding the protective member 100 attached to the wafer 10, the gaps 17 between the component chips 2 can be easily filled with the molding resin 3 during the molding step ST2. As a result, in addition to the advantages of the first and second embodiments, the method for manufacturing a molded chip according to the first modification has the advantage that the side surfaces 8 of the component chips 2 can be covered with a resin molding 3 with a proper thickness. According to the first modification, the expanding drum 92 is used in the expanding step ST20.However, the present invention is not limited to the use of the expanding device 90 having the expanding drum 92, but may use other expanding mechanisms as long as they can expand the protective member 100 in plane directions. Furthermore, according to the present invention, instead of partially cutting the wafer 10 with the cutting blade 35, a laser beam having a wavelength that can be transmitted through the wafer 10 may be applied to the wafer 10 along the projected dividing lines 11 to form modified layers that act as crack initiation points in the wafer 10, and then the back surface 7 of the wafer 10 may be ground to thereby form a chip group of row-arranged device chips 2 according to stealth dicing before grinding (SDBG), so that the device chips 2 can be covered with the resin molding 3. [Second variation]

[0060] Hereinafter, a method of manufacturing a mold chip in accordance with a second modification of the first and second embodiments of the present invention will be described with reference to the drawings. Fig. 18 is a flowchart illustrating the procedure of the method for manufacturing a mold chip according to the second modification of the first and second embodiments. Fig. 19 is a schematic sectional view showing a mold wafer, etc. after a protective member peeling step of the device shown in Fig. 18 illustrates the method for manufacturing a mold chip. Fig. 20 is a schematic, partially sectional side view showing a mold wafer separating step of the Fig. 18 illustrates the method for producing a mold chip. In the Fig. 18 to 20, those parts which are identical to those of the first and second embodiments and the first modification are designated by identical reference numerals and will not be described in detail below.

[0061] As in Fig. As illustrated in Fig. 18, the method for manufacturing a mold chip according to the second modification is the same as the method for manufacturing a mold chip according to the first embodiment, the second embodiment, or the first modification, except that the method includes a protective member peeling step ST21 and the mold wafer separating step ST3 is different. As shown in Fig. As illustrated in Fig. 18, the method for manufacturing a molded chip according to the second modification includes the expanding step ST20. However, in accordance with the present invention, the expanding step ST20 may be omitted.

[0062] The protective element peeling step ST21 is a step in which, after the molding step ST2, an adhesive tape 110 is attached to the back side 7 of the mold wafer 18 and the protective element 100 is peeled off from the end face 5 of the mold wafer 18. According to the second modification, the adhesive tape 110, which has a larger diameter than the mold wafer 18 and has an annular frame 111 attached to its outer edge, is peeled off as shown in Fig. 19, in the protective element peeling step ST21, the adhesive tape 110 is attached to the backside 7 of the mold wafer 18, and the protective element 100 is peeled off. Then, the process proceeds from the protective element peeling step ST21 to the mold wafer separation step ST3. The adhesive tape 110 may be thermally insulating and stretchable like the protective element 100, or it may be non-thermally insulating and non-stretchable.

[0063] In accordance with the second modification, a cutting device 60-2 (see Fig. 20) during the shaped wafer separation step ST3, the back side 7 of the shaped wafer 18 is clamped to a holding surface 62-2 of a chuck table 61-2 via a vacuum with the adhesive tape 110 interposed therebetween, takes an image of the end face 5 of the shaped wafer 18 with an imaging unit (not shown), and performs an alignment process. In accordance with the second modification, the cutting device 60-2 moves the cutting blade 65 during the shaped wafer separation step ST3, as shown in Fig. 20, to cut into the mold wafer 18, based on the captured image, in the transverse direction at the center of a series of columns 17 along one of the projected separation lines 11 from the end face 5 of the mold wafer 18 downwards to the adhesive tape 110, to thereby separate the mold wafer 18 into individual device chips.

[0064] Insofar as the method for manufacturing a molded chip according to the second modification allows the back surfaces 7 and the side surfaces 8 of the component chips 2 to be covered with the molded resin 3 while the components 6 of the molded wafer 18 maintain their relative positions to each other, the method for manufacturing a molded chip according to the second modification is advantageous as in the first and second embodiments because electrodes and electrode bumps on the component sides are prevented from being contaminated by the molded resin 3 and electrical connections of the components 6 are secured. [Third variation]

[0065] Hereinafter, a method of manufacturing a mold chip in accordance with a third modification of the first and second embodiments of the present invention will be described with reference to the drawings. Fig. 21 is a schematic partial sectional side view illustrating a grinding step of the method for manufacturing a mold chip in accordance with the third modification of the first embodiment. Fig. 22 is a schematic sectional view illustrating a molding step of the method for manufacturing a molded chip according to the third modification of the first embodiment. Fig. 23 is a schematic partial sectional side view illustrating a thinning step of the method for manufacturing a mold chip in accordance with the third modification of the second embodiment.

[0066] The method for manufacturing a mold chip in accordance with the third modification is the same as the method for manufacturing a mold chip in accordance with the first embodiment or the second embodiment, except that, as shown in the Fig. 21, Fig. 22 and Fig. 23 illustrates that a protective element 120 is not a protective tape that is thermally insulating and flexible, but rather a hard substrate made of a hard material. Fig. 21, Fig. 22 and Fig. 23 illustrates a grinding step ST14, a molding step ST2, and a thinning step ST15, which are steps of the method for manufacturing a molded chip according to the first embodiment or the second embodiment. In other steps, the protective member 120 is similarly a hard substrate. The protective member 120 according to the third modification is in the form of a circular plate having a larger diameter than the wafer 10 and the molded wafer 18, and is attached to the end face 5 of the wafer 10 by an adhesive member 121.

[0067] Since the method for manufacturing a molded chip according to the third modification allows the back surfaces 7 and the side surfaces 8 of the device chips 2 to be covered with the resin molding 3 while the devices 6 of the wafer 10 maintain their relative positions to each other, the method for manufacturing a molded chip according to the third modification is advantageous as in the first and second embodiments because electrodes and electrode bumps on the device sides are prevented from being contaminated by the resin molding 3 and electrical connections of the devices 6 are secured.

[0068] The present invention is not limited to the above embodiments and modifications. Instead, various changes and modifications can be made without departing from the scope of the invention. Although the thermally insulating protective member 100 is used in the first and second embodiments, etc., in the preparation step ST1, for example, a non-thermally insulating protective member may be attached to the end face of the wafer 10. Before the molding step ST2, the non-thermally insulating protective member may be peeled off, and the thermally insulating protective member 100 may be attached to the wafer 10, that is, to the end faces 5 of the device chips 2.

Claims

[1] Method for manufacturing a shaped chip (1) comprising: a preparatory step (ST1) involving the attachment of component sides of a plurality of component chips (2) arranged in rows to a thermally insulating protective element (100) in order to form a chip group (14) of component chips (2); After the preparation step (ST1), a forming step (ST2) is carried out, involving the addition of a forming resin (3) to the back sides (7) of the component chips (2) and gaps (17) between the component chips (2), in order to form a formed wafer (18) in which the back sides (7) and the side surfaces (8) of the component chips (2) are covered with a resin forming (3); and after the forming step (ST2) a forming wafer separation step (ST3) based on an image in which an end face (5) of the forming wafer (18) has been depicted, with a separation of the forming wafer (18) along the middle of gaps (17) which are filled with the resin forming (3), into forming chips (1). [2] Method for producing a shape chip (1) according to claim 1, wherein the preparation step (ST1) includes a groove formation step (ST12) comprising the formation of grooves (16) in a wafer (10) which has a plurality of areas delimited by a grid of projected parting lines (11) on an end face (5) of the wafer (10), and a plurality of components (6) which are respectively formed in the areas to a depth greater than a final thickness (15), a protective element application step (ST13) comprising the application of the protective element (100) to the end face (5) of the wafer (10) in which the grooves (16) have been formed, and a grinding step (ST14) involving grinding a back side (7) of the wafer (10) to expose the grooves (16) on the wafer (10) and to separate the wafer (10) into the component chips (2). [3] Method for producing a shape chip (1) according to claim 1, wherein the preparation step (ST1) comprises: a thinning step (ST15) comprising grinding a back side (7) of a wafer (10) which has a plurality of areas delimited by a grid of projected parting lines (11) on an end face (5) of the wafer (10), and a plurality of components which are respectively formed in the areas in order to thin the wafer (10) to a final thickness (15), and a separation step (ST16) involving the separation of the diluted wafer (10) along the projected separation lines (11). [4] Method for producing a shaped chip (1) according to any one of the preceding claims, further comprising: After the preparation step (ST1) and before the forming step (ST2), an expansion step (ST20) is performed, in which the protective element (100) is expanded in plane directions to widen the distances between the component chips (2). [5] Method for producing a shaped chip (1) according to any one of the preceding claims, wherein the wafer (10) has a round outer circumferential surface (12), the preparation step (ST1) includes an edge trimming step (ST11) with a trimming of the round section (13) on the end face (5) of the wafer (10) along the outer circumferential edge, and During the forming step (ST2) in a mold, a molding resin (3) supplied to the back (7) of the wafer (10) is pressed against the back (7) of the wafer (10). [6] Method for producing a shaped chip (1) according to any one of the preceding claims, further comprising: after the forming step (ST2) a protective element removal step (ST21) with an application of an adhesive strip (110) to a back side (7) of the forming wafer (18) and removal of the protective element (100) from the front side (5) of the forming wafer (18), wherein the formed wafer (18) is separated from the end face (5) of the formed wafer (18) during the formed wafer separation step (ST3).

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