Chip manufacturing method

Abstract

To provide a method for manufacturing a chip that can improve the accuracy of finishing in manufacturing a chip by dividing, by using plasma etching, a wafer having a substrate and a plurality of devices provided on a front face side of the substrate with an insulating film therebetween.SOLUTION: Prior to formation of a mask used in dividing a wafer by plasma etching (protective film forming step and second laser beam irradiation step), the wafer is irradiated with a laser beam from a front face side of an insulating film along the boundaries of a plurality of devices to form first through paths penetrating the insulating film. In this case, a laser beam irradiation condition for removing desired portions of the insulating film, and a laser beam irradiation condition for forming a mask, that is, for removing desired portions of a protective film can be made suitable. Consequently, the accuracy of finishing in manufacturing a chip by dividing the wafer can be improved.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present invention relates to a method for manufacturing a chip by dividing a wafer having a substrate and a plurality of devices provided on the surface side of the substrate via an insulating film along the boundaries of the plurality of devices.

Background Art

[0002] Chips of devices such as ICs (Integrated Circuits) are essential components in various electronic devices such as mobile phones and personal computers. Such chips are manufactured, for example, by dividing a wafer on which a plurality of devices are formed along the boundaries of the plurality of devices.

[0003] As a method for dividing such a wafer, it has been proposed to provide a mask on the surface of the wafer so that the boundary is exposed and then subject the wafer to plasma etching (see, for example, Patent Document 1). This mask is formed, for example, by covering the surface of the wafer with a protective film containing an absorbent and then irradiating the surface side of the protective film with a laser beam along the boundary to remove a part of the protective film.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] To improve the quality of chips, chips are sometimes manufactured from wafers that have a semiconductor substrate and multiple devices attached to the surface side of the substrate via an insulating film (insulating film), known as SOI (Silicon on Insulator) wafers. These SOI wafers may then be divided using plasma etching, as described above.

[0006] In this case, the laser beam irradiated to form a mask for plasma etching often removes a portion of the insulating film along with a portion of the protective film on the wafer surface. However, this portion of the insulating film is generally not directly removed by the laser beam irradiation.

[0007] Specifically, because insulators have a large bandgap energy, the laser beam generally penetrates the insulating film. On the other hand, the laser beam that has penetrated the insulating film is absorbed by the semiconductor that makes up the substrate. In this case, laser ablation occurs near the surface of the substrate. Along with this laser ablation, a portion of the insulating film located at the boundary of multiple devices is vaporized and removed.

[0008] However, if the insulating film is thick and / or if laser ablation occurs over a wide area of ​​the substrate surface, it may become difficult to remove the desired portion of the insulating film, or a wide portion of the insulating film may be removed, i.e., peeling may occur.

[0009] In view of this, an object of the present invention is to provide a chip manufacturing method that can improve the processing accuracy when manufacturing chips by dividing a wafer having a substrate and a plurality of devices provided on the surface side of the substrate via an insulating film, using plasma etching. [Means for solving the problem]

[0010] According to the present invention, there is a method for manufacturing a chip by dividing a wafer having a substrate and a plurality of devices provided on the surface side of the substrate via an insulating film along the boundaries of the plurality of devices, comprising: a first laser beam irradiation step of irradiating the boundary with a laser beam from the surface side of the insulating film under first irradiation conditions to form a first through-path that penetrates the insulating film and exposes the substrate; a protective film forming step of forming a protective film so as to cover the plurality of devices, the insulating film and the substrate exposed in the first through-path after the first laser beam irradiation step; a second laser beam irradiation step of irradiating the boundary with a laser beam from the surface side of the protective film under second irradiation conditions different from the first irradiation conditions, after the protective film forming step to form a second through-path that penetrates the protective film formed in the first through-path and exposes the substrate; and a division step of performing plasma etching from the surface side of the protective film until the substrate is divided along the boundary after the second laser beam irradiation step.

[0011] Preferably, the insulating film is made of a material through which the laser beam passes. Preferably, in the first laser beam irradiation step, the surface side of the insulating film that is irradiated along the boundary by the laser beam under the first irradiation conditions is exposed at the boundary. [Effects of the Invention]

[0012] In this invention, prior to the formation of a mask used when dividing a wafer by plasma etching (protective film formation step and second laser beam irradiation step), a laser beam is irradiated from the surface side of the insulating film along the boundaries of multiple devices to form a first through-path that penetrates the insulating film. In other words, in this invention, prior to the formation of the mask, a portion of the insulating film located at the boundaries of multiple devices is removed.

[0013] In this case, the irradiation conditions for the laser beam to remove a desired portion of the insulating film and the irradiation conditions for the laser beam to form a mask, i.e., to remove a desired portion of the protective film, can be optimized for each purpose. As a result, the present invention makes it possible to improve the processing accuracy when dividing a wafer to manufacture chips. [Brief explanation of the drawing]

[0014] [Figure 1] Figure 1(A) is a schematic perspective view showing an example of a frame unit including a wafer, and Figure 1(B) is a schematic cross-sectional view showing a cross-section of the frame unit shown in Figure 1(A). [Figure 2] Figure 2 is a schematic flowchart illustrating an example of a chip manufacturing method in which a wafer is divided along the boundaries of multiple devices to produce chips. [Figure 3] Figure 3(A) is a schematic partial cross-sectional side view showing the first laser beam irradiation step, and Figure 3(B) is a schematic partial enlarged cross-sectional view showing the wafer after the first laser beam irradiation step. [Figure 4] Figure 4(A) is a schematic partial cross-sectional side view showing the protective film formation step, and Figure 4(B) is a schematic partial enlarged cross-sectional view showing the wafer after the protective film formation step. [Figure 5] Figure 5 is a schematic, partially enlarged cross-sectional view showing the wafer after the second laser beam irradiation step. [Figure 6] Figure 6 is a schematic diagram showing an example of a plasma generation device used to carry out the segmentation step. [Figure 7] Figure 7 is a schematic, partially enlarged cross-sectional view showing an example of a chip manufactured from a wafer that is divided in the division step. [Modes for carrying out the invention]

[0015] Embodiments of the present invention will be described with reference to the accompanying drawings. FIG. 1(A) is a perspective view schematically showing an example of a frame unit including a wafer, and FIG. 1(B) is a cross-sectional view schematically showing a cross-section of the frame unit shown in FIG. 1(A). The frame unit 11 shown in FIGS. 1(A) and 1(B) includes a wafer 13 used in the manufacture of chips.

[0016] This wafer 13 has a substrate 15 made of a semiconductor such as silicon (Si), for example. An insulating film 17 made of an insulator such as silicon oxide (SiO2) or silicon nitride (Si3N4) is provided on the surface of this substrate 15. The thickness of this insulating film 17 is, for example, 5 μm to 30 μm.

[0017] Furthermore, a plurality of independent devices 19 are provided on the front surface side of the wafer 13. That is, the plurality of devices 19 are provided on the front surface side of the substrate 15 via the insulating film 17. And the plurality of devices 19 are arranged in a matrix on the surface of the insulating film 17. That is, the boundaries of the plurality of devices 19 extend in a grid pattern.

[0018] Also, in the back surface of the wafer 13, that is, in the back surface of the substrate 15, the central region of a disk-shaped tape 21 having a diameter longer than that of the substrate 15 is adhered. This tape 21 has, for example, a flexible film-like base material layer and an adhesive layer (paste layer) provided on one surface (the surface on the substrate 15 side) of the base material layer.

[0019] Specifically, this base material layer is made of polyolefin (PO), polypropylene (PP), polyethylene terephthalate (PET), polyvinyl chloride (PVC), polystyrene (PS), or the like. Also, this adhesive layer is made of an ultraviolet curable silicone rubber, an acrylic material, an epoxy material, or the like.

[0020] Also, an annular frame 23 in which a circular opening 23a having a diameter longer than that of the wafer 13 is formed is adhered to the outer peripheral region of the tape 21. This frame 23 is made of a metal such as aluminum (Al), for example.

[0021] FIG. 2 is a flowchart schematically showing an example of a method for manufacturing a chip by dividing a wafer 13 along the boundaries of a plurality of devices 19. In this method, first, a first through-path for exposing the substrate 15 through the insulating film 17 is formed by irradiating a laser beam from the surface side of the insulating film 17 (first laser beam irradiation step: S1).

[0022] FIG. 3(A) is a partial cross-sectional side view schematically showing the state of the first laser beam irradiation step (S1), and FIG. 3(B) is a partially enlarged cross-sectional view schematically showing the wafer 13 after the first laser beam irradiation step (S1). This first laser beam irradiation step (S1) is carried out, for example, using the laser processing apparatus 2 shown in FIG. 3(A).

[0023] This laser processing apparatus 2 has a holding table 4. This holding table 4 has a disk-shaped frame body 6 made of ceramics or the like. This frame body 6 has a disk-shaped bottom wall 6a and a cylindrical side wall 6b standing upright from the outer edge of this bottom wall 6a. That is, a disk-shaped recess defined by the bottom wall 6a and the side wall 6b is formed on the upper surface side of the frame body 6.

[0024] And a disk-shaped porous plate 8 having a diameter approximately equal to the diameter of this recess is fixed to the recess formed on the upper surface side of the frame body 6. This porous plate 8 is made of, for example, porous ceramics. And when the frame unit 11 is carried into the laser processing apparatus 2, the wafer 13 is placed on the upper surface of the holding table 4 via the tape 21.

[0025] Also, a plurality of clamps 10 are provided around the holding table 4. The plurality of clamps 10 are provided at substantially equal intervals along the circumferential direction of the holding table 4. And when the frame unit 11 is carried into the laser processing apparatus 2, the plurality of clamps 10 grip the frame 23 at a position lower than the upper surface of the holding table 4.

[0026] Furthermore, the porous plate 8 of the holding table 4 communicates with a suction source (not shown), such as an ejector, through a through hole formed in the bottom wall 6a of the frame 6. When the suction source is operated with the frame unit 11 loaded into the laser processing machine 2, a suction force acts on the wafer 13 via the tape 21, and the wafer 13 is held in place by the holding table 4.

[0027] Furthermore, the holding table 4 and the multiple clamps 10 are connected to a horizontal movement mechanism (not shown). This horizontal movement mechanism includes, for example, a ball screw and a motor. When this horizontal movement mechanism is operated, the holding table 4 and the multiple clamps 10 move along the horizontal direction (for example, the front-to-back direction and / or the left-to-right direction).

[0028] Furthermore, a laser irradiation unit head 12 is provided above the holding table 4. This laser irradiation unit has a laser oscillator (not shown) that generates a pulsed laser beam LB with a wavelength (e.g., 355 nm) that penetrates the insulating film 17 and is absorbed by the substrate 15. This laser oscillator has, for example, Nd:YAG as the laser medium.

[0029] The head 12 also houses optical systems such as a focusing lens and mirrors. When a laser beam LB is generated by the laser oscillator, the laser beam LB is irradiated towards the holding table 4 through the optical system housed in the head 12.

[0030] Furthermore, the head 12 is connected to a vertical movement mechanism (not shown). This vertical movement mechanism includes, for example, a ball screw and a motor. When this vertical movement mechanism is operated, the head 12 moves along the vertical direction.

[0031] Then, in the first laser beam irradiation step (S1), with the wafer 13 held on the holding table 4 via the tape 21, the laser beam LB is irradiated along the boundaries of the multiple devices 19.

[0032] Specifically, the holding table 4 is moved so that the laser beam LB, which is irradiated from the head 12 toward the wafer 13, is focused near the surface of the substrate 15, and the laser beam LB is irradiated toward the wafer 13 along the boundaries of multiple devices 19 (see Figure 3(A)).

[0033] In the first laser beam irradiation step (S1), the irradiation conditions of the laser beam LB are set to be suitable for removing a desired portion of the insulating film 17. Specifically, the laser beam LB at this time is set to have a power of, for example, 3W to 5W, typically 4W, and a frequency of, for example, 1500kHz to 2500kHz, typically 2000kHz.

[0034] Furthermore, the laser beam LB forms a circular focal point in a plan view, and the diameter of this focal point is set to, for example, 8 μm or less, preferably 6 μm or less. The movement speed of the holding table 4 at this time is set to, for example, 300 mm / s to 500 mm / s, typically 400 mm / s.

[0035] As a result, the laser beam LB passes through the insulating film 17 and is absorbed by the substrate 15, causing laser ablation near the surface of the substrate 15. Along with this laser ablation, a portion of the insulating film 17 located at the boundaries of the multiple devices 19 is vaporized and removed. Consequently, a first through-passage 25 is formed in the wafer 13 that penetrates the insulating film 17 and exposes the surface of the substrate 15 (see Figure 3(B)).

[0036] After the first laser beam irradiation step (S1), a protective film is formed to cover the multiple devices 19, the insulating film 17, and the substrate 15 exposed in the first through-passage 25 (protective film formation step: S2). Figure 4(A) is a schematic partial cross-sectional side view showing the protective film formation step (S2), and Figure 4(B) is a schematic partial enlarged cross-sectional view showing the wafer 13 after the protective film formation step (S2).

[0037] This protective film formation step (S2) is carried out, for example, using a coating apparatus 14 shown in Figure 4(A). This coating apparatus 14 has a holding table 16 having a structure similar to the holding table 4 described above, and a plurality of clamps 18 having a structure similar to the plurality of clamps 10 described above. The holding table 16 is also in communication with a suction source (not shown), such as an ejector, similar to the holding table 4 described above.

[0038] Furthermore, the holding table 16 and the multiple clamps 18 are connected to a rotating mechanism (not shown). This rotating mechanism includes, for example, a pulley and a motor. When this rotating mechanism is operated, the holding table 16 and the multiple clamps 18 rotate around a straight line passing through the center of the upper surface of the holding table 16 and aligned vertically as the axis of rotation.

[0039] Furthermore, a resin supply nozzle 20 is provided above the holding table 16 to supply liquid resin L to the surface of the wafer 13 contained in the frame unit 11 held by the holding table 16. This liquid resin L is a solution containing, for example, a water-soluble resin such as polyvinylpyrrolidone or polyvinyl alcohol and an organic solvent such as propylene glycol monomethyl ether.

[0040] The water-soluble resin is the main component of the protective film formed by drying the liquid resin L. The organic solvent reduces the surface tension of the liquid resin L, thereby reducing uneven coating when the liquid resin L is applied to the wafer 13. The liquid resin L may also contain a light-absorbing agent such as ferulic acid. This light-absorbing agent absorbs the laser beam LB mentioned above, causing laser ablation in the protective film.

[0041] Then, in the protective film formation step (S2), a protective film is formed on the surface of the wafer 13 held on the holding table 16 via the tape 21 by a so-called spin coating method. Specifically, a predetermined amount of liquid resin L is supplied from the resin supply nozzle 20 to the vicinity of the center of the surface of the wafer 13 (see Figure 4(A)). Then, the holding table 16 is rotated at a predetermined speed (for example, 1500 rpm to 3000 rpm).

[0042] This coats the entire surface of the wafer 13 with liquid resin L. Specifically, the liquid resin L is applied so as to cover the multiple devices 19, the insulating film 17, and the substrate 15 exposed in the first through-passage 25. Then, the rotation of the holding table 16 is stopped, and the liquid resin L is allowed to dry. As a result, a water-soluble protective film 27 is formed that covers the surface of the wafer 13 (see Figure 4(B)).

[0043] After the protective film formation step (S2), a second through-pass is formed by irradiating the protective film 27 from the surface side with a laser beam LB, thereby penetrating the protective film 27 formed in the first through-pass 25 and exposing the substrate 15 (second laser beam irradiation step: S3). Figure 5 is a schematic partially enlarged cross-sectional view showing the wafer 13 after the second laser beam irradiation step (S3).

[0044] This second laser beam irradiation step (S3) is performed, for example, using the laser processing apparatus 2 shown in Figure 3(A). In the second laser beam irradiation step (S3), with the wafer 13 held on the holding table 4 via the tape 21, the laser beam LB is irradiated along the boundaries of the multiple devices 19.

[0045] Specifically, the holding table 4 is moved so that the laser beam LB, which is irradiated from the head 12 toward the wafer 13, is focused near the surface of the substrate 15, and the laser beam LB is irradiated onto the wafer 13 along the boundaries of multiple devices 19.

[0046] In the second laser beam irradiation step (S3), the irradiation conditions of the laser beam LB are set to be suitable for removing a desired portion of the protective film 27. Specifically, the laser beam LB at this time is set to have a power of, for example, 0.5W to 3W, typically 1W, and a frequency of, for example, 100kHz to 1500kHz, typically 500kHz.

[0047] Furthermore, the laser beam LB forms a circular focal point in a plan view, and the diameter of this focal point is set to be, for example, 8 μm or less, preferably 6 μm or less. The movement speed of the holding table 4 at this time is set to be, for example, 100 mm / s to 300 mm / s, typically 200 mm / s.

[0048] As a result, the laser beam LB is absorbed, for example, by the photoabsorbent contained in the protective film 27, causing laser ablation in the protective film 27. Consequently, a second through-pass 29 is formed in the wafer 13, penetrating the protective film 27 formed in the first through-pass 25 and exposing the substrate 15 (see Figure 5).

[0049] Following the second laser beam irradiation step (S3), plasma etching is performed from the surface side of the protective film 27 until the substrate 15 is divided along the boundaries of the multiple devices 19 (dividing step: S4). Figure 6 is a schematic diagram showing an example of a plasma generation apparatus used to carry out the dividing step (S4).

[0050] The plasma generator 22 shown in Figure 6 has a chamber 24 made of a conductive material and grounded. The chamber 24 has an inlet / outlet 24a for loading the frame unit 11 into and unloading the frame unit 11 from the inside.

[0051] The loading / unloading port 24a is provided with a gate valve 26 that can either block or allow communication between the internal space and the external space of the chamber 24. The chamber 24 also has an exhaust port 24b for exhausting its internal space.

[0052] This exhaust port 24b is connected to an exhaust device 30 such as a vacuum pump via piping 28, etc. Furthermore, a support member 32 is provided on the inner surface of the chamber 24, and this support member 32 supports the table 34.

[0053] An electrostatic chuck (not shown) is provided on the top of the table 34. Inside the table 34, a disc-shaped electrode 34a is provided, located below the electrostatic chuck. This electrode 34a is connected to the high-frequency power supply 38 via a matching unit 36.

[0054] Furthermore, a disc-shaped opening is formed in the chamber 24 at a position opposite the upper surface of the table 34, and a gas ejection head 42 is provided in this opening, supported by the chamber 24 via a bearing 40. This gas ejection head 42 is made of a conductive material and is connected to a high-frequency power supply 46 via a matching unit 44.

[0055] Furthermore, a cavity (gas diffusion space) 42a is formed inside the gas ejection head 42. In addition, a plurality of gas outlets 42b are formed in the inner part of the gas ejection head 42 (for example, the lower part) that connect the gas diffusion space 42a with the internal space of the chamber 24. In addition, two gas supply ports 42c and 42d are formed in the outer part of the gas ejection head 42 (for example, the upper part) for supplying a predetermined gas to the gas diffusion space 42a.

[0056] Furthermore, gas supply port 42c is connected via piping 48a, etc., to a gas supply source 50a that supplies, for example, carbon fluoride-based gases such as C4F8 and / or sulfur fluoride-based gases such as SF6. Also, gas supply port 42d is connected via piping 48b, etc., to a gas supply source 50b that supplies, for example, inert gases such as Ar and O2 gas.

[0057] Then, in the splitting step (S4), the substrate 15 is split along the boundaries of the multiple devices 19, for example, by the so-called Bosch process. Specifically, first, the frame unit 11 is brought onto the table 34 with the tape 21 facing downwards, while the gate valve 26 connects the internal and external spaces of the chamber 24.

[0058] Next, the wafer 13 is held via the tape 21 by the electrostatic chuck of the table 34. Then, the internal space of the chamber 24 is evacuated by the exhaust device 30 to create a vacuum. Then, isotropic plasma etching, protective film formation, and anisotropic plasma etching are repeatedly performed until the substrate 15 is divided along the boundaries of the multiple devices 19.

[0059] Specifically, this isotropic plasma etching is carried out, for example, by supplying a gas containing SF6 from a gas supply source 50a to the internal space of the chamber 24, and supplying Ar gas from a gas supply source 50b, while providing high-frequency power from a high-frequency power supply 46 to the gas ejection head 42. As a result, the substrate 15 exposed in the second through-passage 29 is isotropically etched by F-based radicals and the like that generated in the internal space of the chamber 24.

[0060] Furthermore, the formation of this protective film is carried out, for example, by supplying a gas containing C4F8 from a gas supply source 50a to the internal space of the chamber 24, and supplying a gas containing Ar from a gas supply source 50b, while simultaneously supplying high-frequency power from a high-frequency power supply 46 to the gas ejection head 42. As a result, CF radicals are deposited on the surface of the substrate 15 exposed in the second through-passage 29, forming a film containing carbon fluoride.

[0061] Alternatively, the formation of this protective film may be carried out by supplying a gas containing O2 and Ar from a gas supply source 50b to the internal space of the chamber 24, and then supplying high-frequency power from a high-frequency power supply 46 to the gas ejection head 42. As a result, the material constituting the substrate 15 exposed in the second through passage 29 (e.g., silicon) reacts with oxygen ions, and an oxide film is formed on the surface of the substrate 15.

[0062] Furthermore, this anisotropic plasma etching is carried out, for example, by supplying a gas containing SF6 from a gas supply source 50a to the internal space of the chamber 24, and supplying Ar gas from a gas supply source 50b, while providing high-frequency power from a high-frequency power supply 38 to an electrode 34a provided inside the table 34, and providing high-frequency power from a high-frequency power supply 46 to a gas ejection head 42. As a result, F-based ions and the like generated in the internal space of the chamber 24 are accelerated toward the table 34, causing the substrate 15 to be etched anisotropically.

[0063] Figure 7 is a schematic, partially enlarged cross-sectional view showing an example of a chip manufactured from a wafer 13 that is divided in the division step (S4). When the substrate 15 is divided along the boundaries of multiple devices 19 by the Bosch process, a chip 31 having an uneven surface shape is manufactured from the wafer 13, as shown in Figure 7.

[0064] In the method shown in Figure 2, prior to the formation of a mask used when dividing the wafer 13 by plasma etching (protective film formation step (S2) and second laser beam irradiation step (S3)), a laser beam LB is irradiated from the surface side of the insulating film 17 along the boundaries of the multiple devices 19 to form a first through-passage 25 that penetrates the insulating film 17. In other words, in the method shown in Figure 2, prior to the formation of the mask, a portion of the insulating film 17 located at the boundaries of the multiple devices 19 is removed.

[0065] In this case, the irradiation conditions of the laser beam LB for removing a desired portion of the insulating film 17 and the irradiation conditions of the laser beam LB for forming a mask, i.e., for removing a desired portion of the protective film 27, can be optimized for each purpose. As a result, the method shown in Figure 2 makes it possible to improve the processing accuracy when dividing the wafer 13 to manufacture the chip 31.

[0066] It should be noted that the above description represents one aspect of the present invention, and the present invention is not limited to the above description. For example, in the above-described division step (S4), the substrate 15 may be divided along the boundaries of the multiple devices 19 by performing only anisotropic plasma etching without performing isotropic plasma etching and protective film formation.

[0067] Furthermore, the structures and methods of the embodiments described above can be modified as appropriate without departing from the scope of the present invention. [Explanation of symbols]

[0068] 2: Laser processing equipment 4: Holding Table 6: Frame (6a: bottom wall, 6b: side wall) 8: Porous board 10: Clamp 11: Frame Unit 12: Head 13: Wafer 14: Coating device 15: Circuit board 16: Holding Table 17: Insulating Film 18: Clamp 19: Device 20: Resin supply nozzle 21: Tape 22: Plasma Generator 23: Frame 24: Chamber (24a: Inlet / Outlet, 24b: Exhaust Port) 25: 1st passage 26: Gate valve 27:Protective film 28: Piping 29:Second passageway 30: Exhaust system 31: Tip 32: Support member 34: Table (32a: Electrode) 36: Matching box 38: High frequency power supply 40: Bearing 42: Gas ejection head (40a: Gas diffusion space, 40b: Gas outlet, 40c, 40d: Gas supply port) 44: Matching box 46:High frequency power supply 48a, 48b: Piping 50a, 50b: Gas supply source

Claims

1. A method for manufacturing a chip, comprising dividing a wafer having a substrate and a plurality of devices provided on the surface side of the substrate via an insulating film along the boundaries of the plurality of devices, A first laser beam irradiation step involves irradiating the insulating film along the boundary from the surface side of the insulating film under first irradiation conditions to form a first penetration path that penetrates the insulating film and exposes the substrate, A protective film forming step is performed after the first laser beam irradiation step, in which a protective film is formed to cover the plurality of devices, the insulating film, and the substrate exposed in the first through-path, A second laser beam irradiation step is performed after the protective film formation step, in which the laser beam is irradiated along the boundary from the surface side of the protective film under second irradiation conditions different from the first irradiation conditions, thereby forming a second through-path that penetrates the protective film formed in the first through-path and exposes the substrate. A division step is performed after the second laser beam irradiation step, in which plasma etching is performed from the surface side of the protective film until the substrate is divided along the boundary, A method for manufacturing a chip equipped with the following features.

2. The method for manufacturing a chip according to claim 1, wherein the insulating film is made of a material through which the laser beam passes.

3. The method for manufacturing a chip according to claim 1 or 2, wherein in the first laser beam irradiation step, the surface side of the insulating film that is irradiated along the boundary by the laser beam under the first irradiation conditions is exposed at the boundary.

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