Method for manufacturing semiconductor device with metal film

Abstract

The present invention provides a method for manufacturing a semiconductor device with a metal film, which reduces the space required for installing an electromagnetic wave shielding component. The method for manufacturing a semiconductor device with a metal film comprises: a cutting groove forming step, in which a cutting tool is cut into the first surface of a workpiece, and a cutting groove having a depth exceeding the finished thickness of the workpiece is formed along a predetermined dividing line; a protective component pasting step, in which, after the cutting groove forming step, a protective component is pasted on the first surface of the workpiece; a grinding step, in which the workpiece is held by a chuck table through the protective component, and the second surface side is ground until the workpiece reaches the finished thickness, thereby dividing the workpiece into a plurality of semiconductor devices; a metal film coating step, in which, after the grinding step, each side surface of the plurality of semiconductor devices to which the protective component is pasted on the first surface side and the second surface side after grinding are coated with a metal film; and a protective component removing step, in which, after the metal film coating step, the protective component is removed from the first surface side.

Description

Technical Field

[0001] The present invention relates to a method for manufacturing a semiconductor device at least a portion of which is covered with a metal film. Background Art

[0002] In recent years, in order to achieve higher functionality and higher performance in mobile wireless communication devices such as mobile phones and smartphones, the number of electronic components such as SAW (Surface Acoustic Wave) devices and antenna elements that constitute the wireless system of mobile wireless communication devices has increased.

[0003] In addition, in order to realize the high functionality and high performance of mobile wireless communication equipment, the data transmission speed of various semiconductor devices such as DRAM (Dynamic Random Access Memory) or flash memory installed in mobile wireless communication equipment has been further increased. As the data transmission speed increases, the electromagnetic waves generated by various semiconductor devices become noise relative to the wireless system, which has a problem of adversely affecting the wireless system.

[0004] Therefore, it is known that a semiconductor device is covered with a metal that functions as an electromagnetic wave shield in order to reduce the influence of electromagnetic wave noise. For example, by covering a semiconductor device with a housing of a thermoplastic resin molded product having metal (for example, see Patent Document 1) or a cover of a metal plate and a wall of a conductive elastic body (for example, see Patent Document 2), electromagnetic wave noise can be reduced.

[0005] Prior art literature

[0006] Patent Literature

[0007] Patent Document 1: Japanese Patent Application Publication No. 2001-44680

[0008] Patent Document 2: Japanese Patent Application Publication No. 2004-72051 Summary of the invention

[0009] Problems to be solved by the invention

[0010] However, when a metal housing or a metal plate cover is used, the space required to install the electromagnetic shield is relatively large, which hinders the miniaturization and thinning of mobile wireless communication devices. The present invention is made in view of this problem and its object is to reduce the space required to install the electromagnetic shield.

[0011] Means for solving problems

[0012] According to one embodiment of the present invention, there is provided a method for manufacturing a semiconductor device with a metal film, which comprises the following steps: a cutting groove forming step, in which a cutting tool is caused to cut into a first surface of a workpiece, the workpiece having the first surface on which electrodes of a semiconductor element are provided in respective regions divided by a plurality of predetermined dividing lines arranged in a grid shape, and a second surface on the side opposite to the first surface, and a cutting groove having a depth exceeding a finished thickness of the workpiece is formed along the predetermined dividing lines; a protective component pasting step, in which, after the cutting groove forming step, a protective component is pasted on the first surface of the workpiece; a grinding step, in which the workpiece is held by a chuck table through the protective component, and the second surface side is ground until the workpiece reaches the finished thickness, thereby dividing the workpiece into a plurality of semiconductor devices; a metal film coating step, in which, after the grinding step, the side surfaces of the plurality of semiconductor devices to which the protective component is pasted on the first surface side and the second surface side after grinding are coated with a metal film; and a protective component removing step, in which, after the metal film coating step, the protective component is removed from the first surface side.

[0013] Preferably, the manufacturing method of a semiconductor device with a metal film further comprises the following steps: a protective film covering step, covering the first surface side with a protective film before the cutting groove forming step; and a protective film removing step, removing the protective film after the protective component removing step, and making the protective component and the protective film tightly fitted in the protective component pasting step.

[0014] In addition, preferably, the manufacturing method of a semiconductor device with a metal film further includes a laser processing groove forming step, after the protective film covering step and before the cutting groove forming step, the first surface side of the workpiece formed with the protective film is irradiated with a laser beam to form a laser processing groove wider than the cutting groove along the predetermined dividing line.

[0015] In addition, preferably, the manufacturing method of a semiconductor device with a metal film further includes a protective film removal line forming step, after the protective film coating step and before the laser processing groove forming step, the protective film is irradiated with a laser beam having a wavelength that is absorptive to the protective film along the predetermined dividing line, thereby forming a protective film removal line obtained by removing the protective film along the predetermined dividing line with a width wider than either the cutting groove and the laser processing groove.

[0016] In addition, preferably, the manufacturing method of a semiconductor device with a metal film further includes a debris removal step, wherein the workpiece is treated with an etching gas after the laser processing groove forming step or the cutting groove forming step and before the protective component pasting step to remove debris attached to at least any one of the laser processing groove and the cutting groove.

[0017] In addition, preferably, the method for manufacturing a semiconductor device with a metal film further comprises an adhesive tape sticking step of sticking an adhesive tape to the second surface side covered with the metal film in the plurality of semiconductor devices after the metal film covering step and before the protective component removing step.

[0018] In addition, preferably, the protective component pasted in the protective component pasting step is an expandable adhesive tape, and the manufacturing method of a semiconductor device with a metal film further comprises an expansion step, after the grinding step and before the metal film coating step, the protective component is expanded to widen the interval between each semiconductor device.

[0019] Effects of the Invention

[0020] In a method for manufacturing a semiconductor device with a metal film of one embodiment of the present invention, the metal film is coated on each side surface of the semiconductor device and the second surface ground to the finished thickness, thereby reducing the space required for installing the electromagnetic wave shielding part compared to the case of using a metal shell or a metal plate cover. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a perspective view showing an example of a workpiece.

[0022] Figure 2 (A) is a diagram showing a cutting groove forming step (S10), Figure 2 (B) is a diagram showing a protective component pasting step (S20), Figure 2 (C) is a diagram showing the grinding step (S30).

[0023] Figure 3 (A) is a diagram showing the metal film coating step (S40), Figure 3 (B) is a diagram showing the adhesive tape pasting step (S50), Figure 3 (C) is a diagram showing the protective member removal step (S60).

[0024] Figure 4 This is a flowchart of the method for manufacturing the semiconductor device with a metal film according to the first embodiment.

[0025] Figure 5 (A) is a diagram showing a protective film coating step (S5), Figure 5 (B) is a cross-sectional view showing a wafer having a protective film formed on the front side, Figure 5 (C) is a diagram showing the cutting groove forming step (S10).

[0026] Figure 6 (A) is a diagram showing a protective component pasting step (S20), Figure 6(B) is a diagram showing a grinding step (S30), Figure 6 (C) is a diagram showing the metal film coating step (S40).

[0027] Figure 7 (A) is a diagram showing the adhesive tape pasting step (S50), Figure 7 (B) is a diagram showing the protective component removal step (S60), Figure 7 (C) is a diagram showing the protective film removal step (S65).

[0028] Figure 8 This is a flowchart of a method for manufacturing a semiconductor device with a metal film according to the second embodiment.

[0029] Fig. 9 (A) is a diagram showing a protective film coating step (S5), Fig. 9 (B) is a partial cross-sectional side view showing a state where the front surface side of the wafer is processed using a laser beam.

[0030] Fig.10 (A) is an enlarged view showing a laser processed groove, Fig.10 (B) is an enlarged view showing the protective film removal line, Fig.10 (C) is an enlarged view of a laser processed groove formed in the laser processed groove forming step (S8) after the protective film removal line forming step (S7).

[0031] Fig.11 (A) is a diagram showing a fragment removal step (S9), Fig.11 (B) is a diagram showing the cutting groove forming step (S10).

[0032] Fig.12 (A) is a diagram showing a protective component pasting step (S20), Fig.12 (B) is a diagram showing the grinding step (S30).

[0033] Fig.13 (A) is a diagram showing the metal film coating step (S40), Fig.13 (B) is a diagram showing the adhesive tape sticking step (S50).

[0034] Fig.14 This is a flowchart of a method for manufacturing a semiconductor device with a metal film according to a third embodiment.

[0035] Fig.15 (A) is a diagram showing a cutting groove forming step (S10), Fig.15 (B) is a diagram showing the fragment removal step (S9) of the second modification example.

[0036] Fig.16(A) is a diagram showing a protective component pasting step (S20), Fig.16 (B) is a diagram showing the grinding step (S30).

[0037] Fig.17 (A) is a diagram showing the expansion step (S35), Fig.17 (B) is a diagram showing the metal film coating step (S40).

[0038] Fig.18 This is a flow chart of a method for manufacturing a semiconductor device with a metal film according to a fourth embodiment. DETAILED DESCRIPTION

[0039] An embodiment of one aspect of the present invention will be described with reference to the drawings. Figure 1 1 is a perspective view showing an example of a workpiece. The workpiece of this embodiment is a disk-shaped wafer 11. The wafer 11 has a semiconductor substrate 11c, which is mainly composed of silicon (Si) and is formed into a disk shape with a thickness of about 500 μm to 1000 μm (see Figure 2 (A)).

[0040] It should be noted that there is no limitation on the material, shape, structure, size, etc. of the semiconductor substrate 11c. For example, a semiconductor material other than silicon such as gallium arsenide (GaAs) or silicon carbide (SiC) may be used as the semiconductor substrate 11c.

[0041] A disk-shaped functional layer 15c thinner than the semiconductor substrate 11c is provided on the semiconductor substrate 11c (see Figure 2 (A)). A semiconductor element (not shown) such as IC (Integrated Circuit) or LSI (Large Scale Integration) is formed by the region on the functional layer 15c side of the semiconductor substrate 11c and the functional layer 15c.

[0042] The functional layer 15c is provided with an electrode 15d of a semiconductor element electrically connected to the active region of the semiconductor substrate 11c constituting the semiconductor element. In addition, the functional layer 15c has a low dielectric constant insulator layer (so-called Low-k material layer) 15e that functions as an interlayer insulating layer between the plurality of electrodes 15d. It should be noted that the upper end of each electrode 15d is exposed from the low dielectric constant insulator layer 15e.

[0043] In addition, in this embodiment, the surface of the wafer 11 on the functional layer 15c side is referred to as the front surface (first surface) 11a. And the surface of the semiconductor substrate 11c on the side opposite to the functional layer 15c is referred to as the back surface (second surface) 11b of the wafer 11. In this way, the front surface 11a and the back surface 11b are located on opposite sides of the wafer 11.

[0044] On the front surface 11a of the wafer 11, device regions 15a including active regions of the semiconductor substrate 11c and functional layers 15c constituting the semiconductor elements are formed in regions divided by a plurality of predetermined dividing lines (streets) 13 arranged in a grid.

[0045] The electrode 15d is exposed on the front surface 11a of the device region 15a, and a plurality of bumps (projecting electrodes) 15b formed into spherical shapes by metal materials such as solder are arranged on the electrode 15d. It should be noted that there is no limitation on the type, number, shape, structure, size, and arrangement of the device region 15a and the bumps 15b.

[0046] In this embodiment, the bump 15b is provided on the front side 11a of the wafer 11, but the bump 15b may not be provided. In addition, the workpiece may be a so-called WL-CSP (wafer level chip size package) wafer, the front side 11a of which is molded with a sealing resin and configured in such a way that the bump 15b protrudes from the sealing resin. In addition, the workpiece may also be a resin package substrate in which a plurality of device chips are sealed with a molding resin.

[0047] The wafer 11 has a device portion having a plurality of device regions 15a and a peripheral remaining portion surrounding the device portion on the front side 11a. A notch 11d indicating the crystal orientation is provided at the peripheral end of the peripheral remaining portion of the wafer 11. It should be noted that an orientation flat surface or the like may be provided instead of the notch 11d.

[0048] Then use Figure 2 , Figure 3 and Figure 4 A method for manufacturing the semiconductor device 21 with a metal film according to the first embodiment will be described. In the first embodiment, first, a cut groove is formed on the wafer 11 (cut groove forming step ( S10 )). Figure 2 (A) is a diagram showing the cutting groove forming step (S10).

[0049] In the first embodiment, a cutting groove is formed using a cutting device (not shown). The cutting device includes a chuck table (not shown) for sucking and holding the back side 11b of the wafer 11. The chuck table is connected to a rotating mechanism (not shown) such as a motor, and can rotate around a rotation axis substantially parallel to the Z-axis direction.

[0050] In addition, a table moving mechanism (not shown) is provided below the chuck table, and the chuck table can be moved along the X-axis direction (processing feed direction) by the table moving mechanism. It should be noted that the X-axis, Y-axis (described later) and Z-axis constitute an orthogonal coordinate system.

[0051] The holding surface of the chuck table is connected to a suction source (not shown) via a suction passage (not shown) formed inside the chuck table. By applying negative pressure from the suction source to the holding surface, the back side 11b of the wafer 11 is sucked and held by the chuck table.

[0052] The cutting device further includes a cutting unit (not shown) for cutting the wafer 11. The cutting unit has a spindle (not shown) as a rotation axis substantially parallel to the Y-axis direction (indexing feed direction).

[0053] The spindle is rotated by a rotational drive source (not shown) such as a motor connected to one end thereof. In addition, an annular tool holder (not shown) is rotatably fixed integrally to the other end of the spindle located on the opposite side to the rotational drive source.

[0054] A so-called hub-type cutting tool 20 is mounted on the spindle via a tool holder. The cutting tool 20 of this embodiment has an annular base (not shown) and an annular cutting blade 22 provided on the outer periphery of the base. The cutting blade 22 is formed by mixing abrasive grains such as diamond and cBN (cubic boron nitride) in a bonding material such as metal or resin.

[0055] In the cutting groove forming step (S10), first, a dicing tape (not shown) is attached to the back side 11b of the wafer 11, and the back side 11b of the wafer 11 is placed on the holding surface of the chuck table through the dicing tape. Next, the negative pressure of the suction source is activated, and the wafer 11 is sucked and held by the chuck table in a state where the front side 11a of the wafer 11 is exposed upward.

[0056] Thereafter, the cutting unit is lowered toward the chuck table while the cutting tool 20 is rotated at high speed, so that the cutting tool 20 cuts into the front surface 11a side of the wafer 11. However, in the cut groove forming step (S10), the wafer 11 is not completely cut.

[0057] In the cut groove forming step (S10), a cut groove 17 having a predetermined depth greater than the finished thickness T1 of the wafer 11 and not reaching the back surface 11b of the wafer 11 is formed (see Figure 2 (B)), adjust the cutting depth of the cutting tool 20.

[0058] Next, the cutting tool 20 and the chuck table are relatively moved along the X-axis direction while maintaining the cutting depth of the cutting tool 20. Thus, a cutting groove 17 is formed on the wafer 11 along the X-axis direction from one end to the other end of one planned dividing line 13 (that is, the wafer 11 is cut in half).

[0059] After the cut groove 17 is formed along one planned dividing line 13, the cutting unit is moved in the Y-axis direction. Then, the cut groove 17 is similarly formed from one end to the other end of another planned dividing line 13 adjacent to the one planned dividing line 13 in the Y-axis direction.

[0060] After the cutting grooves 17 are formed along all the predetermined dividing lines 13 extending in one direction, the chuck table is rotated 90 degrees by the rotating mechanism, and the cutting grooves 17 are formed again along all the predetermined dividing lines 13 extending in other directions orthogonal to the one direction. Thus, the cutting grooves 17 of a predetermined depth are formed on all the predetermined dividing lines 13 arranged in a grid shape on the front surface 11a side of the wafer 11.

[0061] After the cut groove forming step ( S10 ), the protective member 19 is attached to the front surface 11 a of the wafer 11 (protective member attaching step ( S20 )). Figure 2 (B) is a diagram showing the protective member sticking step (S20).

[0062] The protective member 19 has, for example, a resin base material layer having substantially the same diameter as the wafer 11. The base material layer has, for example, a thickness of 5 μm to 200 μm, and is made of a polymer material such as polyolefin (PO), polyvinyl chloride (PVC), polystyrene (PS), or ethylene vinyl acetate (EVA).

[0063] In addition, the protective component 19 has an adhesive layer on the front side of the base layer. The adhesive layer is, for example, a layer composed of a resin adhesive that solidifies when irradiated with heat or ultraviolet rays and reduces the adhesive force. The adhesive layer can be provided in a ring shape at the circular end region of the base layer, or can be provided on the entire surface of the base layer. It should be noted that the protective component 19 may not be provided with an adhesive layer.

[0064] The protective member 19 is bonded to the front surface 11a side of the wafer 11 in a releasable manner using an adhesive layer. In addition, the protective member 19 is deformed in a manner that imitates the concave-convex structure such as the bump 15b in the device region 15a of the wafer 11. For example, one surface of the protective member 19 is bonded to the front surface 11a of the wafer 11 and the surface of the bump 15b. It should be noted that, in the case where the protective member 19 does not have an adhesive layer, the base material layer is bonded to the front surface 11a side in a releasable manner.

[0065] In the protective member sticking step (S20), a protective member sticking device (not shown) is used to stick the protective member 19 on the front surface 11a of the wafer 11. The protective member sticking device includes a chamber (not shown) connected to a suction source (not shown) for decompressing the inside of the chamber.

[0066] Furthermore, a support table (not shown) is provided in the chamber for supporting the wafer 11. The support table is moved in a predetermined direction (eg, X-axis direction) by, for example, a ball screw type moving mechanism.

[0067] The protective member sticking device has a delivery mechanism for delivering a rolled tape body (not shown) to the upper side of the support table. The tape body is composed of a protective member 19 and a release sheet.

[0068] In addition, the protective member sticking device has a peeling unit (not shown) for peeling the protective member 19 from the release sheet when the tape is sent to the top of the support workbench. The protective member 19 peeled from the release sheet by the peeling unit is sent to the top of the support workbench by the sending mechanism in a manner that the adhesive layer of the protective member 19 is opposite to the support workbench.

[0069] The protective member sticking device further includes a pressing roller for pressing the base layer side of the protective member 19 fed above the support table. The pressing roller presses the base layer side of the protective member 19, and presses the adhesive layer side of the protective member 19 to the support table.

[0070] In the protective component pasting step (S20), the back side 11b of the wafer 11 is first placed on the support table. Then, the pressure in the chamber is reduced by a suction source. By reducing the pressure in the chamber, air, dust, and other foreign matter can be prevented from entering between the front side 11a of the wafer 11 and the protective component 19.

[0071] After that, while the rolled tape is fed onto the support table, the release sheet is peeled off from the tape by a peeling unit, and the protective member 19 is attached to the front surface 11a of the wafer 11 disposed on the support table by a pressing roller. By providing the protective member 19 on the front surface 11a of the wafer 11, damage to the front surface 11a side of the wafer 11 in subsequent processing steps can be prevented.

[0072] It should be noted that the use of a chamber connected to a suction source to reduce the internal pressure is not essential, and the protective member sticking device can also stick the protective member 19 to the front surface 11a of the wafer 11 under atmospheric pressure. In this case, the protective member sticking device is composed of the above-mentioned support workbench, delivery mechanism, peeling unit, pressing roller, etc.

[0073] It should be noted that, when the protective member 19 is not provided with an adhesive layer, the support table may be heated in the protective member sticking step ( S20 ), thereby sticking the protective member 19 to the wafer 11 while softening and deforming the protective member 19 .

[0074] The softened protection member 19 deforms to imitate the uneven structure of the front surface 11a of the wafer 11, and can therefore be closely attached to the front surface 11a of the wafer 11. It should be noted that the heating temperature can be appropriately adjusted according to the material of the protection member 19 so as to reach the softening point of each material.

[0075] Alternatively, instead of heating the support table, hot air may be blown to the protection member 19 to soften and deform the protection member 19. When hot air is blown, the protection member 19 is pressed against the front surface 11a of the wafer 11 by the wind pressure, so that the protection member 19 can be closely attached to the front surface 11a of the wafer 11 without using a pressing roller.

[0076] After the protective member attaching step ( S20 ), the back surface 11 b of the wafer 11 is ground until the wafer 11 reaches a finished thickness, thereby dividing the wafer 11 into a plurality of semiconductor devices 21 (grinding step ( S30 )). Figure 2 (C) is a diagram showing the grinding step (S30).

[0077] In the grinding step (S30), the wafer 11 is ground using a grinding device 30. The grinding device 30 includes a chuck table 32 that sucks and holds the front surface 11a side of the wafer 11 via the protective member 19. The chuck table 32 is connected to a rotating mechanism (not shown) such as a motor, and rotates around a rotation axis that is substantially parallel to the Z-axis direction.

[0078] A disk-shaped porous member is provided on the front side of the chuck table 32, and the front side of the porous member serves as a holding surface 32a of the chuck table 32. Negative pressure from a suction source (not shown) acts on the holding surface 32a through a flow path formed inside the chuck table 32, thereby generating a suction force that sucks the front side 11a of the wafer 11.

[0079] A grinding mechanism 34 is disposed above the chuck table 32 in a manner opposite to the holding surface 32a. The grinding mechanism 34 includes a spindle (not shown) that rotates around a rotation axis that is substantially parallel to the Z-axis direction. The spindle is raised and lowered along the Z-axis direction by a lifting mechanism (not shown). A disc-shaped grinding wheel mounting seat (not shown) is fixed to the lower end side of the spindle.

[0080] A grinding wheel 36 having substantially the same diameter as the grinding wheel mounting seat is mounted on the lower surface of the grinding wheel mounting seat. The grinding wheel 36 includes an annular grinding wheel base 38a formed of a metal material such as aluminum or stainless steel.

[0081] The grinding wheel base 38a is fixed to the main shaft by attaching the upper surface side of the grinding wheel base 38a to the grinding wheel mounting seat. In addition, a plurality of grinding tools (grinding tool sheets) 38b are provided on the lower surface of the grinding wheel base 38a.

[0082] Each grinding stone 38 b has a substantially rectangular parallelepiped shape, and is arranged in a ring shape over the entire circumference of the annular lower surface of the grinding wheel base 38 a with gaps provided between adjacent grinding stones 38 b .

[0083] The grinding tool 38b is formed by mixing abrasive grains such as diamond and cBN (cubic boron nitride) in a bonding material such as metal, ceramic, or resin. The bonding material and abrasive grains are not limited and are appropriately selected according to the specifications of the grinding tool 38b.

[0084] In the grinding step (S30) of the present embodiment, first, the wafer 11 provided with the protective member 19 is moved from the protective member attaching device to the chuck table 32 of the grinding device 30. Then, negative pressure from a suction source (not shown) is applied to the holding surface 32a, and the front surface 11a side of the wafer 11 is sucked and held by the holding surface 32a via the protective member 19.

[0085] Thereafter, the main shaft of the grinding mechanism 34 is lowered while the chuck table 32 and the main shaft of the grinding mechanism 34 are rotated in predetermined directions, and the grinding stone 38 b is pressed against the back surface 11 b side of the wafer 11 .

[0086] The back side 11b of the wafer 11 is removed by an amount corresponding to the thickness T2, and the thickness of the wafer 11 becomes the finished thickness T1. The cut groove 17 is formed deeper than the finished thickness T1, so when the wafer 11 is thinned to the finished thickness T1, the semiconductor substrate 11c is divided with the cut groove 17 as a boundary, and the wafer 11 is divided into a plurality of semiconductor devices 21.

[0087] After the grinding step (S30), the back side of the wafer 11 (i.e., the back side 11e of the semiconductor device 21) and each side 11f of the semiconductor device 21 (i.e., each side of the semiconductor substrate 11c and the functional layer 15c) after grinding to the finished thickness are coated with a metal film (metal film coating step (S40)). The metal film 23 is a thin film of a metal such as copper (Cu), aluminum (Al), nickel (Ni) or stainless steel. Figure 3 (A) is a diagram showing the metal film coating step (S40).

[0088] In the metal film coating step (S40), a physical vapor deposition (PVD) device or a chemical vapor deposition (CVD) device is used to form a metal film 23 on the wafer 11. As PVD, vacuum evaporation, sputtering, ion plating, etc. are used. As CVD, plasma CVD, etc. are used.

[0089] In this embodiment, a high-frequency magnetron sputtering device (not shown, hereinafter referred to as a sputtering device) is used to form the metal film 23. The sputtering device includes a processing chamber (not shown), and a holding table (not shown) is provided inside the processing chamber for holding the wafer 11 by electrostatic method or other methods. In addition, a target material (not shown) as a material of the metal film 23 is provided above the holding table in a state supported by an excitation member (not shown).

[0090] A high frequency power source (not shown) is connected to the target. In addition, an inlet (not shown) for introducing a sputtering gas such as argon (Ar) and an exhaust port (not shown) connected to a reduced pressure source (not shown) are provided in the processing chamber.

[0091] In the metal film coating step (S40), the wafer 11 with the protective member 19 attached to the front surface 11a is first placed on a holding table in the processing chamber via the protective member 19, and the wafer 11 is held by electrostatic method or other methods. That is, the back surface 11e of the ground semiconductor device 21 faces the target. Next, the processing chamber is sealed, and the interior of the processing chamber is vented from the exhaust port to reduce the pressure.

[0092] Next, a high-frequency power source applies high-frequency power to the target material magnetized by the excitation component, and a sputtering gas is introduced from the inlet to generate plasma. When the sputtering gas ions in the plasma collide with the target material, metal particles are ejected from the target material, and the metal is deposited on the back surface 11e and the side surface 11f of the semiconductor device 21.

[0093] The thickness of the metal film 23 is, for example, 2 μm to 10 μm, more preferably 3 μm to 8 μm. The metal film 23 functions as an electromagnetic wave shield for shielding electromagnetic wave noise emitted from the semiconductor device 21 .

[0094] Thus, in this embodiment, a metal film 23 of the micron order serving as an electromagnetic wave shielding component is directly formed on the back side 11e and the side surface 11f of the semiconductor device 21, thereby being able to reduce the space required for installing the electromagnetic wave shielding component compared to the prior art which uses a metal shell or a metal plate cover.

[0095] In addition, in the metal film coating step (S40), the metal film 23 can be simultaneously formed on the plurality of semiconductor devices 21 attached to the protective member 19. Therefore, compared with the case where each semiconductor device is covered with a metal casing or the like as in the prior art, the semiconductor device 21 can be covered with an electromagnetic wave shielding member more effectively.

[0096] After the metal film coating step ( S40 ), the adhesive tape 27 is attached to the plurality of semiconductor devices 21 and the metal ring-shaped frame 25 to form the frame unit 29 (adhesive tape attaching step ( S50 )). Figure 3 (B) is a cross-sectional view of the frame unit 29 in the adhesive tape applying step (S50).

[0097] In the adhesive tape pasting step (S50), first, the plurality of semiconductor devices 21 and the protective component 19 are arranged in the opening of the frame 25 so that the metal film 23 is located on the upper side. Then, a circular resin adhesive tape 27 having a larger diameter than the opening of the frame 25 is pasted on the frame 25, the plurality of semiconductor devices 21 and the protective component 19. Figure 3 In (B), the image is shown upside down.

[0098] Thus, the adhesive tape 27 is attached to the back surface 11 e side of the semiconductor device 21 covered with the metal film 23 , and the protective member 19 , the plurality of semiconductor devices 21 , and the frame 25 are integrated by the adhesive tape 27 to form a frame unit 29 .

[0099] After the adhesive tape applying step ( S50 ), the protective member 19 is removed from the front surface 11 a side of the wafer 11 (protective member removing step ( S60 )). Figure 3 (C) is a cross-sectional view of the frame unit 29 in the protective member removing step (S60).

[0100] When the protective member 19 has an adhesive layer, in the protective member removal step ( S60 ), an ultraviolet irradiation device or a heating device is used to reduce the adhesive force of the adhesive layer of the protective member 19 , and then the protective member 19 is peeled off from the front surface 11 a side of the wafer 11 .

[0101] When the protective member 19 has no adhesive layer, the protective member 19 can be peeled off from the front surface 11a without treating the protective member 19 with ultraviolet rays etc. After the protective member 19 is removed, each semiconductor device 21 is taken out from the adhesive tape 27 using a pickup device (not shown) etc.

[0102] Figure 41 is a flowchart of a method for manufacturing a semiconductor device 21 with a metal film 23 according to the first embodiment. As described above, in this embodiment, the metal film 23 can be directly formed on the back surface 11e and the side surface 11f of the semiconductor device 21, so that the space required for installing the electromagnetic wave shielding member can be reduced. In addition, the metal film 23 is formed on all semiconductor devices 21 at the same time, so that the semiconductor devices 21 can be covered more effectively with the electromagnetic wave shielding member.

[0103] Then use Figures 5 to 8 The second embodiment is described below. In the second embodiment, a protective film covering step (S5) of covering the front surface 11a side of the wafer 11 with a protective film is further provided before the cut groove forming step (S10).

[0104] Figure 5 (A) is a diagram showing a protective film coating step (S5), Figure 5 (B) is a cross-sectional view of the wafer 11 in which the protective film 45 is formed on the front surface 11 a side.

[0105] In the protective film coating step (S5), a protective film forming device 40 is used to form a protective film 45 on the front surface 11a of the wafer 11. The protective film forming device 40 includes, for example, a rotary table mechanism (not shown) and a liquid receiving mechanism (not shown) provided around the periphery and bottom of the rotary table mechanism.

[0106] The rotary table mechanism includes: a circular rotary table (not shown), a cylindrical support member (not shown) supporting the rotary table, and a motor (not shown) that drives the rotary table to rotate by the support member. Figure 5 Rotate in the direction of the arrow (A).

[0107] The rotary table has a suction holding portion formed of a porous material, and the suction holding portion is connected to a suction source (not shown). The wafer 11 placed on the suction holding portion of the rotary table is suction-held by the negative pressure from the suction source.

[0108] It should be noted that the liquid receiving mechanism includes a liquid receiving container (not shown) surrounding the periphery and bottom of the rotary table mechanism and a cover member (not shown) mounted on the support member.

[0109] The protective film forming device 40 further includes a liquid resin ejection unit (not shown) for ejecting liquid resin toward the front surface 11a side of the wafer 11 held on the rotating table. The liquid resin ejection unit includes: an arm having a substantially L shape, a liquid resin ejection nozzle 42 for ejecting liquid resin provided at the front end of the arm, and a motor for swinging the arm. The liquid resin ejection nozzle 42 is connected to a liquid resin supply source (not shown) via the arm.

[0110] The protective film forming device 40 also serves as a cleaning device for cleaning the wafer 11. The protective film forming device 40 includes a cleaning liquid ejecting unit (not shown) for cleaning the wafer 11 held on the rotary table at a position different from the liquid resin ejecting unit.

[0111] The cleaning liquid spraying unit includes a substantially L-shaped arm and a cleaning liquid spraying nozzle 46 (see FIG. 4 ) disposed at the front end of the arm and spraying the cleaning liquid 48, similarly to the liquid resin spraying unit. Figure 7 (C)), and a motor for swinging the arm. The cleaning liquid spray nozzle 46 is connected to a cleaning liquid supply source (not shown) via the arm.

[0112] The process of the protective film coating step ( S5 ) will be described. First, the wafer 11 is placed on the suction holding portion of the rotary table so that the front surface 11 a side of the wafer 11 faces the liquid resin ejection nozzle 42 .

[0113] Then, the back side 11b of the wafer 11 is sucked and held by the rotary table by negative pressure from the suction source. Then, the motor is driven to rotate the wafer 11 and the rotary table integrally. It should be noted that at this time, the cleaning liquid spray nozzle 46 is retracted from above the rotary table.

[0114] Afterwards, if Figure 5 As shown in (A), while the rotating table is rotated at a low speed (for example, 30 rpm to 50 rpm) in the direction of the arrow, the liquid resin spraying nozzle 42 is swung in an arc shape on the rotating table in a manner transverse to the rotation center of the rotating table, and liquid resin 44 is dripped onto the chip 11 from the liquid resin spraying nozzle 42.

[0115] The liquid resin spreads uniformly on the front surface 11a of the wafer 11 and the surface of the bump 15b under the action of centrifugal force. The protective film 45 is formed to a thickness of, for example, about 1 μm to 20 μm in a manner that reflects the bumps 15b and the like, imitating the bumps on the front surface 11a of the wafer 11 (see FIG. Figure 5 (B)).

[0116] The protective film 45 is a heat-resistant and chemical-resistant resin film, such as a vinyl chloride film. In this embodiment, the protective film 45 is formed using a rotary table mechanism, but a sheet-like protective film 45 may be attached to the front surface 11 a of the wafer 11 instead.

[0117] When the sheet-shaped protective film 45 is attached to the front surface 11a side, the thickness of the protective film 45 can be adjusted in advance before being attached to the front surface 11a side. Therefore, compared with the case where the protective film 45 is formed using a rotary table mechanism, the thickness of the protective film 45 can be easily adjusted. For example, compared with the case where the protective film 45 is formed using a rotary table mechanism, the thickness of the protective film 45 can be made thicker, reaching about 5 μm to 200 μm.

[0118] After the protective film coating step ( S5 ), a cut groove forming step ( S10 ) is performed. Figure 5 (C) is a diagram showing the cutting groove forming step (S10). In the cutting groove forming step (S10) of the second embodiment, the protective film 45 is cut using the cutting device, and the cutting groove 17 is formed on the wafer 11 in the same manner as in the first embodiment (see Figure 6 ).

[0119] After the cut groove forming step ( S10 ), a protective member attaching step ( S20 ) is performed. Figure 6 (A) is a diagram showing the protective component pasting step (S20). In the protective component pasting step (S20) of the second embodiment, the protective component pasting device described above is also used to paste the protective component 19 on the front surface 11a side of the wafer 11 so that the protective component 19 and the protective film 45 are in close contact.

[0120] Thus, in the second embodiment, the protective member 19 is provided on the front surface 11a side of the wafer 11 via the protective film 45. Therefore, after the protective member 19 is peeled off from the wafer 11, even if the adhesive layer of the protective member 19 remains on the front surface 11a of the wafer 11 and the bump 15b, the adhesive layer can be removed together when the protective film 45 is removed. Therefore, it is possible to prevent the adhesive layer of the protective member 19 from remaining on the front surface 11a of the semiconductor device 21.

[0121] After the protective member sticking step (S20), a grinding step (S30) is performed. Figure 6 (B) is a diagram showing the grinding step (S30). In the grinding step (S30) of the second embodiment, the back side 11b of the wafer 11 is also removed by an amount corresponding to the thickness T2, and the wafer 11 is processed to a finished thickness T1. Thus, the semiconductor substrate 11c is divided with the cut groove 17 as a boundary, and the wafer 11 is formed into a plurality of semiconductor devices 21.

[0122] After the grinding step ( S30 ), a metal film coating step ( S40 ) is performed. Figure 6 (C) is a diagram showing the metal film coating step (S40). In the metal film coating step (S40) of the second embodiment, the metal film 23 is also formed on the back surface 11e and the side surface 11f of the semiconductor device 21 by PVD or CVD.

[0123] After the metal film coating step (S40), an adhesive tape applying step (S50) is performed. Figure 7 (A) is a diagram showing the adhesive tape sticking step (S50). In the adhesive tape sticking step (S50), the frame unit 29 is formed in the same manner as in the first embodiment.

[0124] After the adhesive tape applying step ( S50 ), the protective member 19 is removed from the front surface 11 a side of the wafer 11 (protective member removing step ( S60 )). Figure 7 (B) is a diagram showing the protective member removing step (S60). It should be noted that the protective film 45 is in close contact with the front surface 11a of the wafer 11, and the entire protective film 45 is not peeled off from the front surface 11a in the protective member removing step (S60).

[0125] Therefore, in the method for manufacturing the semiconductor device 21 with the metal film 23 of the second embodiment, after the protective member removing step (S60), a protective film removing step (S65) is performed to remove the protective film 45. In the protective film removing step (S65), the protective film forming device 40 which also serves as a cleaning device is used to remove the protective film 45. Figure 7 (C) is a diagram showing the protective film removal step (S65).

[0126] To explain the process of removing the protective film 45, first, the side of the adhesive tape 27 opposite to the semiconductor device 21 (ie, the back surface 27b side) is placed on the suction and holding portion of the rotary table so that the front surface 11a side is positioned upward.

[0127] Then, the rotary table sucks and holds the back surface 27b of the adhesive tape 27 by negative pressure from the suction source. Next, the motor is driven to rotate the frame unit 29 and the rotary table integrally. It should be noted that at this time, the liquid resin ejection nozzle 42 is retracted from above the rotary table.

[0128] Thereafter, while the rotary table is rotated at, for example, 800 rpm, the cleaning liquid discharge nozzle 46 is swung in an arc shape on the rotary table, and the cleaning liquid 48 (for example, isopropyl alcohol (IPA)) is dripped onto the wafer 11 .

[0129] like Figure 7 As shown in (C), the protective film 45 is dissolved in the cleaning liquid 48 to become the used solution A, which is blown to the outside of the semiconductor device 21 under the action of centrifugal force and received by the liquid receiving container. In this way, the protective film 45 is removed from the front side 11a of the wafer 11 by the cleaning liquid 48. It should be noted that in the case where the sheet-like protective film 45 is attached to the front side 11a, the protective film 45 can be peeled off in the same manner as the protective component 19 in the protective component removal step (S60).

[0130] Figure 8 This is a flow chart of a method for manufacturing a semiconductor device 21 with a metal film 23 according to the second embodiment. In the second embodiment, the protective member 19 is provided on the front surface 11a side of the wafer 11 via the protective film 45, so that the adhesive layer of the protective member 19 can be prevented from remaining on the front surface 11a of the semiconductor device 21.

[0131] In the second embodiment, the metal film 23 can be directly formed on the back surface 11e and the side surface 11f of the semiconductor device 21, similarly to the first embodiment, so that the space required for installing the electromagnetic shielding member can be reduced. In addition, the metal film 23 is formed on all semiconductor devices 21 at the same time, so that the semiconductor devices 21 can be effectively covered with the electromagnetic shielding member.

[0132] Next, use Figures 9 to 14 In the third embodiment, first, the protective film 45 is formed on the front surface 11 a side of the wafer 11 using the protective film forming apparatus 40 in the same manner as in the second embodiment (protective film coating step ( S5 )). Fig. 9 (A) is a diagram showing the protective film coating step (S5).

[0133] In the third embodiment, after the protective film coating step (S5) and before the cutting groove forming step (S10), the front surface 11a side of the wafer 11 formed with the protective film 45 is irradiated with a laser beam L to form a laser processed groove 51 along the planned dividing line 13.

[0134] Fig. 9 (B) is a partial cross-sectional side view showing a state where the front surface 11a side of the wafer 11 is processed by the laser beam L. For example, the protective film 45 and the functional layer 15c are ablated by irradiation with the laser beam L to form a laser processed groove 51 (laser processed groove forming step (S8)). Fig.10 (A) is an enlarged view showing the laser processed groove 51. It should be noted that, Fig.10 (A) indicates Fig. 9 Area B of (B).

[0135] The laser processing groove forming step (S8) is performed using the laser processing device 50. The laser processing device 50 has a chuck table (not shown) for holding the back surface 11b side of the wafer 11 by suction.

[0136] In addition, a processing head 52 is provided at a position opposite to the chuck table for irradiating the front surface 11a of the wafer 11 held by the chuck table with a pulsed laser beam L. The laser beam L has a wavelength that is absorptive to the protective film 45 and the wafer 11 (i.e., absorbed by the protective film 45 and the wafer 11), for example, a wavelength of 355 nm.

[0137] The holding surface of the chuck table is connected to a suction source (not shown) via a suction passage (not shown) formed inside the chuck table. By applying negative pressure from the suction source to the holding surface, the back side 11b of the wafer 11 is sucked and held by the chuck table.

[0138] Furthermore, a support table (not shown) is provided below the chuck table, and the support table is movable in a predetermined direction (eg, X-axis direction) by a ball screw type moving mechanism.

[0139] When the protective film 45 and the wafer 11 are processed by the laser beam L, for example, one predetermined dividing line 13 is parallel to the X-axis direction in which the chuck table moves. And, while the laser beam L is irradiated to the front surface 11a side of the wafer 11, the processing head 52 and the chuck table are relatively moved in the X-axis direction. Although it depends on the width of the laser beam L, the laser beam L can be irradiated along one predetermined dividing line 13 once or multiple times.

[0140] Thus, the protective film 45 and the functional layer 15 c are removed by ablation along the planned dividing lines 13 , and a laser processed groove 51 reaching the semiconductor substrate 11 c is formed along the planned dividing lines 13 .

[0141] In addition, by moving and rotating the chuck table in the Y-axis direction, laser processed grooves 51 are formed along all the predetermined dividing lines 13. It should be noted that the laser processed grooves 51 have a width W4 (see FIG. 1 ) greater than the width W4 of the cut groove 17 formed in the subsequent cut groove forming step (S10). Fig.11 (B)) Wider width W1 (ie, W4 <W1)。

[0142] In this embodiment, a laser processing groove 51 having a width W1 is formed by using a laser beam L. In the subsequent cutting groove forming step (S10), the cutting tool 20 is positioned within the width W1, and the semiconductor substrate 11c is cut by using the cutting tool 20. As a result, compared with the case where the functional layer 15c and the protective film 45 are cut by using the cutting tool 20, it is possible to prevent the film peeling of the functional layer 15c, so that a higher-quality cutting process can be performed. In addition, the protective film 45 can prevent debris generated during the ablation process from adhering to the device region 15a.

[0143] In the subsequent metal film coating step ( S40 ), metal film 23 is formed on laser processed groove 51 . At this time, metal film 23 is also formed on side portion 57 of protective film 45 exposed to the inside of laser processed groove 51 .

[0144] However, the protective film 45 is finally removed in the protective film removal step (S65), so the metal film 23 provided on the side portion 57 of the protective film 45 becomes protruding in the space, and the metal film 23 provided on the side of the functional layer 15c exposed to the inner side of the laser processing groove 51 is easily peeled off by being slightly triggered. Therefore, the effect of the electromagnetic wave shielding member brought by the metal film 23 may be reduced.

[0145] Therefore, in the first modification of the third embodiment, a step portion is formed by exposing a portion of the functional layer 15c from the protective film 45. In this first modification, after the protective film coating step (S5) and before the laser processing groove forming step (S8), the protective film 45 is irradiated with a laser beam L along the planned dividing line 13. The protective film 45 is removed by ablation along the planned dividing line 13, and a protective film removal line 53 is formed (protective film removal line forming step (S7)).

[0146] The protective film removal line 53 has a width W2 that is wider than either the width W3 of the laser processed groove 55 formed in the laser processed groove forming step ( S8 ) or the width W4 of the cut groove 17 formed in the cut groove forming step ( S10 ). Fig.10 (B) is an enlarged view of the protective film removal line 53. It should be noted that Fig.10 (B) shows

[0147] Fig. 9 Area B of (B).

[0148] For example, after the spot of the laser beam L in the protective film 45 is shaped to be wide corresponding to the width W2, the laser beam L is irradiated to the front surface 11a of the wafer 11 along the planned dividing line 13. Thus, the protective film removal line 53 can be formed.

[0149] Alternatively, the spot of the laser beam L in the protective film 45 may be circular instead of being shaped to be wide. In this case, the laser beam L is irradiated onto the front surface 11a of the wafer 11 so that the trajectory of the laser beam L partially overlaps in the width direction of the width W2 (i.e., in the direction orthogonal to the planned dividing line 13).

[0150] After the protective film removal line forming step (S7), a laser beam L is irradiated from the front surface 11a of the wafer 11 toward the functional layer 15c located inside the width W2 to form a laser processed groove 55 (laser processed groove forming step (S8)). The laser processed groove 55 has a width W3 (i.e., W4) that is wider than the width W4 of the cut groove 17 and narrower than the width W2 of the protective film removal line 53. <W3<W2)。

[0151] For example, in the laser processing groove forming step (S8) of the first modified example, the laser beam L is reduced in size compared to the protective film removal line forming step (S7), thereby increasing the power density (W / cm 2 ), the functional layer 15c located inside the width W2 is ablated. Thus, a laser processed groove 55 having a width W3 narrower than the protective film removal line 53 and reaching the semiconductor substrate 11c can be formed.

[0152] Fig.10 (C) is an enlarged view showing a laser processed groove 55 formed by the laser processed groove forming step (S8) of the first modified example after the protective film removal line forming step (S7). It should be noted that, Fig.10 (C) shows Fig. 9 The area B of (B). Fig.10 As shown in (C), in the first modification, a step portion 59b is formed by a side portion 59a of the functional layer 15c exposed inside the laser processed groove 55 and the upper surface of the functional layer 15c in the region where the protective film 45 is removed.

[0153] In the subsequent metal film coating step (S40), the metal film 23 is formed in contact with the step portion 59b of the functional layer 15c. In particular, the metal film 23 is formed on the upper surface of the functional layer 15c, so as to be in contact with the step portion 59b of the functional layer 15c. Fig.10 Compared with the case where the metal film 23 is formed in the laser processed groove 51 shown in (A), the metal film 23 can be more firmly bonded to the functional layer 15c. Fig.10 Compared with the example shown in (A), the metal film 23 is less likely to be peeled off from the side portion 59a of the functional layer 15c.

[0154] In the third embodiment, the debris removal step (S9) is performed after the laser processing groove forming step (S8), or after the protective film removal line forming step (S7) and the laser processing groove forming step (S8) and before the protective member pasting step (S20). Thus, the debris of the functional layer 15c attached to the laser processing groove 55 is removed.

[0155] Fig.11 (A) is a diagram showing the debris removal step (S9). It should be noted that, in the following, the diagram shows a wafer 11 that has undergone the protective film removal line formation step (S7) and the laser processing groove formation step (S8) described as the first variation of the third embodiment.

[0156] The debris removal step (S9) is performed using a plasma etching apparatus 60. The plasma etching apparatus 60 of the present embodiment is a remote plasma etching apparatus that makes an etching gas into a plasma state and then introduces the etching gas in the plasma state into a vacuum chamber.

[0157] The plasma etching apparatus 60 includes a vacuum chamber (not shown) having a processing space therein. In addition, a stage base (not shown) for supporting the wafer 11 is provided in the processing space.

[0158] A disc-shaped electrostatic chuck table (not shown) having a smaller diameter than the disc portion is disposed on the upper surface of the disc portion of the table base. The electrostatic chuck table includes a table body formed of an insulating material and a plurality of electrodes embedded in the table body, and the wafer 11 is held by electrostatic adsorption generated by each electrode. Each electrode is connected to a DC power supply capable of generating a high voltage of about 5 kV, for example.

[0159] A supply nozzle (not shown) is provided on the upper wall of the vacuum chamber for supplying raw material gas in a plasma state to the chip 11 held by the electrostatic chuck worktable, and one or more gas supply sources (not shown) are connected in parallel on the upstream side of the flow path connected to the supply nozzle via valves (not shown), flow controllers (not shown), etc.

[0160] The number of types of gases supplied from one or more gas supply sources can be changed according to the debris to be removed. The debris mainly comes from the functional layer 15c. For example, when the low dielectric constant insulator layer 15e in the functional layer 15c is an oxide of a silicon oxide system (SiOCH system), a gas containing perfluorocyclobutane (C4F8) or sulfur hexafluoride (SF6) is supplied from the gas supply source.

[0161] In addition, for example, when the low dielectric constant insulator layer 15e in the functional layer 15c is an organic substance different from the carbon-containing silicon oxide system, a gas containing hydrogen (H2) is supplied from the first gas supply source, and a gas containing nitrogen (N2) is further supplied from the second gas supply source.

[0162] An electrode for applying a high-frequency voltage to the mixed gas flowing through the supply nozzle is provided between a supply port formed at the downstream end of the supply nozzle and a gas supply source. A high-frequency power source is connected to the electrode. The high-frequency power source supplies 0.5 kW to 5 kW of power to the electrode at a high-frequency voltage of about 450 kHz to 2.45 GHz (e.g., 13.56 MHz).

[0163] By applying a high-frequency voltage to the mixed gas flowing through the supply nozzle using a high-frequency power supply or the like, the mixed gas can be converted into plasma (typically, converted into radicals or ions). The mixed gas in a plasma state is supplied from the supply port of the supply nozzle to the processing space.

[0164] In the fragment removal step (S9) of the present embodiment, the chip 11 is first moved into the processing space of the vacuum chamber of the above-mentioned remote plasma etching device, and the back side 11b of the chip 11 is placed on the upper surface of the electrostatic chuck workbench in a manner that the front side 11a of the chip 11 is exposed upward.

[0165] Then, a DC voltage is applied to the electrodes of the electrostatic chuck stage, and the wafer 11 is attracted and held by the electrostatic chuck stage by static electricity. In addition, the processing space is evacuated and the pressure in the processing space is reduced to, for example, about 200Pa.

[0166] After that, the raw material gas and the inert gas are supplied from each gas supply source at a predetermined flow rate. In addition, a high-frequency voltage is supplied from a high-frequency power supply to the electrode to plasmatize (radicalize, ionize, etc.) the mixed gas of the raw material gas and the inert gas. Thus, the etching gas P in a plasma state can be supplied from the supply port of the supply nozzle to the processing space.

[0167] The etching gas P in a plasma state supplied from the supply port is supplied to the front surface 11a side of the wafer 11 disposed below the supply port, and the debris present in the laser processed groove 55 is removed. Thus, compared with the case where the debris is not removed by the etching gas P, the metal film 23 formed in the subsequent metal film coating step (S40) can be more firmly bonded to the functional layer 15c.

[0168] It should be noted that in the debris removal step (S9), the debris can also be removed by supplying a reactive gas that has not been plasmatized to the laser processing groove 55. As the reactive gas, for example, chlorine trifluoride (ClF3), xenon difluoride (XeF2), etc. are used. In addition, the debris can also be removed by supplying a mixed gas of a reactive gas and an inert gas such as nitrogen (N2), argon (Ar), helium (He), etc.

[0169] After the debris removing step (S9), a cut groove forming step (S10) is performed. Fig.11 (B) is a diagram showing the cut groove forming step (S10). In the cut groove forming step (S10), the cut groove 17 having a width W4 is formed inside the laser processed groove 55 using the above-mentioned cutting device.

[0170] After the cut groove forming step ( S10 ), a protective member attaching step ( S20 ) is performed. Fig.12(A) is a diagram showing the step of pasting the protective member (S20). In the step of pasting the protective member (S20), the protective member 19 is set on the front side 11a of the wafer 11 using the protective member pasting device. It should be noted that the protective member 19 is in close contact with the protective film 45 but is not in contact with the front side 11a of the wafer 11, so that a space is formed between the upper surface of the functional layer 15c of the step portion 59b and the front side of the protective member 19 on the wafer 11 side.

[0171] After the protective member sticking step (S20), a grinding step (S30) is performed. Fig.12 (B) is a diagram showing a grinding step (S30). For example, the wafer 11 is processed to a finished thickness T1 using the above-mentioned grinding device 30. Thus, the wafer 11 is divided into semiconductor devices 21.

[0172] After the grinding step ( S30 ), a metal film coating step ( S40 ) is performed. Fig.13 (A) is a diagram showing the metal film coating step (S40). For example, the metal film 23 is formed on the back surface 11e, the side surface 11f, and the upper surface of the step portion 59b of the semiconductor device 21 by high-frequency magnetron sputtering using the above-mentioned sputtering device.

[0173] As described above, the metal film 23 is formed on the upper surface of the functional layer 15c of the step portion 59b, so the metal film 23 is not easily peeled off from the side surface of the functional layer 15c (i.e., the surface of the side portion 59a) even if the protective film 45 is removed. Therefore, even after the protective film removal step (S65), the metal film 23 is not easily peeled off from the side surface 11f of the semiconductor device 21.

[0174] The adhesive tape applying step (S50) is performed after the metal film coating step (S40) and before the protective member removing step (S60). Fig.13 (B) is a diagram showing the adhesive tape sticking step (S50).

[0175] In the adhesive tape pasting step (S50), as described above, the protective member 19 and the plurality of semiconductor devices 21 are integrated together with the annular frame 25 and the circular adhesive tape 27 to form a frame unit 29. By forming the frame unit 29, it is easier to handle the plurality of semiconductor devices 21 in subsequent steps compared to a case where the frame unit 29 is not formed.

[0176] After the adhesive tape applying step (S50), the protective component removing step (S60) is performed. As described above, in the protective component removing step (S60), after the adhesive force of the adhesive layer of the protective component 19 is reduced by using an ultraviolet irradiation device or a heating device, the protective component 19 is peeled off from the front surface 11a side of the wafer 11. It should be noted that, when the protective component 19 does not have an adhesive layer, the protective component 19 can also be peeled off from the front surface 11a side without treating the protective component 19 with ultraviolet rays or the like.

[0177] After the protective member removing step (S60), the protective film removing step (S65) is performed. As described above, in the protective film removing step (S65), the protective film 45 is removed using the protective film forming device 40 which also serves as a cleaning device.

[0178] After the protective film removal step (S65), each semiconductor device 21 can be taken out from the adhesive tape 27 using the above-mentioned pickup device (not shown). In this way, a semiconductor device 21 having a metal film 23 of the order of μm as an electromagnetic wave shield can be obtained.

[0179] Fig.14 This is a flowchart of a method for manufacturing a semiconductor device 21 with a metal film 23 according to a third embodiment. In the third embodiment, when the protective film removal line 53 is formed (Yes in S6), the protective film removal line forming step (S7) and the laser processing groove forming step (S8) are sequentially performed, and the process proceeds to the debris removal step (S9). On the other hand, when the protective film removal line 53 is not formed (No in S6), only the laser processing groove forming step (S8) is performed, and the process proceeds to the debris removal step (S9).

[0180] Next, a second modification of the third embodiment will be described. In the second modification, a cutting groove forming step (S10) and a debris removing step (S9) are sequentially performed after the laser processing groove forming step (S8). This point is different from the first modification.

[0181] In the second modification of the third embodiment, after the laser processing groove forming step ( S8 ), the cutting groove forming step ( S10 ) is performed using the above-mentioned cutting device. Fig.15 (A) is a diagram showing the cutting groove forming step (S10).

[0182] Furthermore, after the cutting groove forming step (S10) and before the subsequent protective component pasting step (S20), the chip 11 is treated with a plasma-generated etching gas P to remove debris attached to the laser-processed groove 55 and the cutting groove 17 (debris removal step (S9)). Fig.15 (B) is a diagram showing the fragment removal step (S9) of the second modification example.

[0183] In the second modification of the third embodiment, in addition to the fragments of the functional layer 15c generated by laser ablation, the fragments generated in the cut groove 17 are removed by etching gas P. As a result, the metal film 23 formed by the subsequent metal film coating step (S40) can be more firmly adhered to the semiconductor substrate 11c and the functional layer 15c, compared with the case where the etching gas P is not used. After the fragment removal step (S9), the protective component pasting step (S20) is performed. The subsequent steps are the same as those of the third embodiment.

[0184] It should be noted that, as described above, in the debris removing step ( S9 ), the debris may be removed by supplying a reactive gas that has not been converted into plasma to the laser processed groove 55 , or by using a mixed gas of a reactive gas and an inert gas.

[0185] Then use Figures 16 to 18 The fourth embodiment will be described. The following mainly describes the differences between the third embodiment and the fourth embodiment. In the fourth embodiment, similarly to the third embodiment, the protective film coating step (S5) to the cut groove forming step (S10) are first performed.

[0186] After the cutting groove forming step (S10), the protective component pasting step (S20) is performed. However, in the protective component pasting step (S20) of the fourth embodiment, the protective component 19 pasted on the front surface 11a side of the wafer 11 is an adhesive tape that expands radially (i.e., has expansibility) under the action of external force.

[0187] In the protective member pasting step (S20), the wafer 11 having the protective film 45 formed on the front surface 11a side is arranged in the opening of the metal ring-shaped frame 25, and in this state, the protective member pasting device (not shown) is used to paste the protective member 19 on the frame 25 and the front surface 11a side of the wafer 11. Thus, a frame unit 29 is formed in which the wafer 11, the frame 25, and the protective member 19 are integrated. Fig.16 (A) is a diagram showing the protective member sticking step (S20).

[0188] After the protective member attaching step ( S20 ), a grinding step ( S30 ) is performed using the grinding device 30 to divide the wafer 11 into a plurality of semiconductor devices 21 . Fig.16 (B) is a diagram showing the grinding step (S30).

[0189] After the grinding step ( S30 ) and before the metal film coating step ( S40 ), the protective member 19 is expanded to widen the intervals between the semiconductor devices 21 (expanding step ( S35 )). In the expanding step ( S35 ), the protective member 19 is expanded in the radial direction using, for example, an expanding device 70 . Fig.17 (A) is a diagram showing the expansion step (S35).

[0190] The expansion device 70 includes a cylindrical drum 72 having a diameter larger than that of the wafer 11. A plurality of rollers 74 are provided along the circumferential direction on the top of the drum 72. The frame unit 29 is placed on the drum 72 so that the back surface 19b of the protective member 19 located on the side opposite to the semiconductor device 21 contacts the rollers 74.

[0191] The expansion device 70 has an annular metal inner ring 76 disposed on the back surface 19b side of the protection member 19. The inner ring 76 is supported so that its lower end is horizontal in the radial direction and its upper end is in contact with the back surface 19b of the protection member 19.

[0192] The expansion device 70 further includes an annular outer ring 78 made of metal, which is arranged on the semiconductor device 21 side (i.e., the front surface 19a side) of the protection member 19, and the inner diameter of the outer ring 78 is larger than the outer diameter of the inner ring 76. The outer ring 78 is configured such that its lower end is in contact with the front surface 19a of the protection member 19 and its upper end is pressed.

[0193] The annular inner ring 76 and outer ring 78 are coaxially arranged and are configured to be relatively movable in a direction approaching each other. In addition, the difference between the outer diameter of the inner ring 76 and the inner diameter of the outer ring 78 is smaller than the thickness of the protective member 19. When the inner ring 76 and the outer ring 78 move relatively and reach the same height position, the protective member 19 is sandwiched between the outer periphery of the inner ring 76 and the inner periphery of the outer ring 78 and is fixed.

[0194] The expansion device 70 further includes a frame holding unit (not shown). The frame holding unit includes a frame support table (not shown) provided so as to surround the upper end of the drum 72 from the outer peripheral side. The frame support table has an opening with a diameter larger than the diameter of the drum 72 and is arranged at the same height as the upper end of the drum 72. In addition, clamps (not shown) are provided at multiple positions on the outer peripheral side of the frame support table.

[0195] When the frame unit 29 is placed on the drum 72 so that the frame 25 is disposed on the frame support table and the frame 25 is fixed by a clamp, the frame unit 29 is fixed by the frame support table.

[0196] The frame support platform is supported by a plurality of rods (not shown) extending in the vertical direction. A cylinder (not shown) supported by a disc-shaped base (not shown) for raising and lowering the rod is provided at the lower end of each rod. When each cylinder is in a contracted state, the frame support platform is pulled down relative to the drum 72.

[0197] In the expansion step (S35), first, the height of the frame support platform is adjusted by operating the air cylinder so that the height of the upper end of the drum 72 coincides with the height of the upper surface of the frame support platform. Next, the frame unit 29 is placed on the drum 72 and the frame support platform. Thereafter, the frame 25 is fixed to the frame support platform using a clamp.

[0198] Next, the air cylinder is operated to pull the frame support of the frame holding unit downward relative to the drum 72. Fig.17 As shown in (A), the protection component 19 is expanded in the radial direction.

[0199] When the protective member 19 is radially expanded, the interval between the semiconductor devices 21 supported by the protective member 19 increases. Therefore, in the subsequent metal film coating step (S40), metal is more likely to be deposited on the semiconductor devices 21 than when the expansion step (S35) is not performed.

[0200] More specifically, on the side surface 11f of the semiconductor device 21 (i.e., the side surface of the semiconductor substrate 11c and the functional layer 15c) and the upper surface of the step portion 59b (see Fig.10 (C). It should be noted that Fig.17 In (A), the upper surface of the step portion 59b faces downward, which makes it easy for metal to accumulate.

[0201] After the protection member 19 is expanded, the inner ring 76 and the outer ring 78 are relatively moved so as to approach each other, and the protection member 19 is sandwiched between the outer periphery of the inner ring 76 and the inner periphery of the outer ring 78. Thus, the protection member 19 is fixed by the inner ring 76 and the outer ring 78 in the expanded state.

[0202] Then, the protective member 19 is cut in a circular shape along the outer circumference of the outer ring 78 at a position between the outer ring 78 and the roller 74 to form a ring unit 80 (see Fig.17 (B)). Thus, the expansion step (S35) is ended.

[0203] After the expansion step (S35), a metal film coating step (S40) is performed using the above-mentioned sputtering device, etc. In the metal film coating step (S40), the ring unit 80 is arranged on the holding table in such a manner that the back surface 19b of the protective member 19 contacts the front surface of the holding table of the sputtering device.

[0204] Thereafter, a metal film 23 is formed on the back surface 11 e and the side surface 11 f of the semiconductor device 21 using a sputtering device. Fig.17 (B) is a diagram showing the metal film coating step (S40). It should be noted that the flowchart of the method for manufacturing the semiconductor device 21 with the metal film 23 according to the fourth embodiment is shown in Fig.18In the fourth embodiment, similarly to the third embodiment, after the metal film coating step ( S40 ), the adhesive tape applying step ( S50 ) and subsequent steps are sequentially performed.

[0205] In addition, the structures, methods, etc. of the above-mentioned embodiments may be appropriately modified and implemented without departing from the scope of the purpose of the present invention. For example, the expansion step (S35) in the fourth embodiment may be applied to the first and second embodiments.

[0206] In addition, in the first to fourth embodiments and the first and second variations of the third embodiment, a semiconductor device 21 with a metal film 23 is manufactured from a workpiece having a semiconductor substrate 11c and a functional layer 15c, but in the case where the workpiece is a WL-CSP chip or a resin packaging substrate, a semiconductor packaging device with a metal film 23 can also be manufactured from the workpiece.

[0207] Explanation of symbols

[0208] 11 Wafer (processed object)

[0209] 11a Front (side 1)

[0210] 11b Back side (side 2)

[0211] 11c Semiconductor substrate

[0212] 11d Notch

[0213] 11e Back

[0214] 11f Side

[0215] 13 Predetermined dividing line (separation lane)

[0216] 15a Device area

[0217] 15b Bump (protruding electrode)

[0218] 15c Functional layer

[0219] 15d Electrode

[0220] 15e Low dielectric constant insulator layer

[0221] 17 Cutting groove

[0222] 19 Protective components

[0223] 19a Front

[0224] 19b Back

[0225] 20 Cutting tools

[0226] 21 Semiconductor devices

[0227] 22 cutting edge

[0228] 23 metal film

[0229] 25 Frame

[0230] 27 Adhesive tape

[0231] 27b Back

[0232] 29 frame units

[0233] 30 Grinding device

[0234] 32 Chuck workbench

[0235] 32a Holding surface

[0236] 34 Grinding mechanism

[0237] 36 Grinding Wheel

[0238] 38a Grinding wheel base

[0239] 38b Grinding tools

[0240] 40 Protective film forming device (cleaning device)

[0241] 42 Liquid resin spray nozzle

[0242] 44 Liquid resin

[0243] 45 Protective film

[0244] 46 Cleaning fluid spray nozzle

[0245] 48 Cleaning fluid (IPA)

[0246] 50 Laser processing equipment

[0247] 52 Processing head

[0248] 51 Laser Processing Slot

[0249] 53 Protective film removal line

[0250] 55 Laser Processing Slot

[0251] 57 Side

[0252] 59a Side

[0253] 59b Steps

[0254] 60 Plasma Etching Device

[0255] 70 Extension device

[0256] 72 Drums

[0257] 74 Rollers

[0258] 76 inner ring

[0259] 78 Outer ring

[0260] 80 Ring Unit

[0261] A After use solution

[0262] Area B

[0263] L Laser beam

[0264] P Etching Gas

[0265] T1 Finished Thickness

[0266] T2 Thickness

[0267] W1,W2,W3,W4 Width

Claims

1. A method for manufacturing a semiconductor device with a metal film, characterized in that: It has the following steps: A cutting groove forming step, wherein a cutting tool is inserted into a first surface of a workpiece, the workpiece having the first surface on which electrodes of a semiconductor element are provided in respective regions divided by a plurality of predetermined dividing lines arranged in a grid shape, and a second surface on a side opposite to the first surface, and a cutting groove having a depth exceeding a finished thickness of the workpiece is formed along the predetermined dividing lines; a step of sticking a protective member on the first surface of the workpiece after the cutting groove forming step; A grinding step of holding the workpiece by a chuck table through the protective member and grinding the second surface side until the workpiece reaches a finished thickness, thereby dividing the workpiece into a plurality of semiconductor devices; a metal film coating step of coating the side surfaces of the plurality of semiconductor devices to which the protective member is attached on the first surface side and the ground second surface side with a metal film after the grinding step; and a protective member removing step of removing the protective member from the first surface side after the metal film coating step, It further comprises the following steps: a protective film coating step of coating the first surface side with a protective film before the cutting groove forming step; a protective film removing step of removing the protective film after the protective member removing step; a laser processing groove forming step, after the protective film coating step and before the cut groove forming step, irradiating the first surface side of the workpiece on which the protective film is formed with a laser beam to form a laser processing groove having a width wider than the cut groove along the predetermined dividing line; and a protective film removal line forming step of irradiating the protective film along the predetermined dividing line with a laser beam having a wavelength that is absorptive to the protective film after the protective film coating step and before the laser processed groove forming step, thereby forming a protective film removal line obtained by removing the protective film along the predetermined dividing line with a width wider than that of either the cut groove or the laser processed groove, In the protective member sticking step, the protective member and the protective film are brought into close contact with each other.

2. The method for manufacturing a semiconductor device with a metal film according to claim 1, wherein: It further comprises a debris removal step, in which the workpiece is treated with an etching gas after the laser processing groove forming step or the cutting groove forming step and before the protective component pasting step to remove debris attached to at least one of the laser processing groove and the cutting groove.

3. The method for manufacturing a semiconductor device with a metal film according to claim 1 or 2, wherein: The method further comprises a step of sticking an adhesive tape to stick an adhesive tape to the second surface of the plurality of semiconductor devices covered with the metal film after the metal film covering step and before the protective member removing step.

4. The method for manufacturing a semiconductor device with a metal film according to claim 1 or 2, wherein: The protective member pasted in the protective member pasting step is an expandable adhesive tape, and an expansion step is further provided after the grinding step and before the metal film coating step to expand the protective member to widen the interval between the semiconductor devices.

Images