Manufacturing method of element chip

Abstract

To suppress an asymmetry of a groove shape when forming a groove by a lase scribing onto a substrate.SOLUTION: A manufacturing method of an element chip, comprises: a step of preparing a substrate having a semiconductor layer and a wiring layer formed onto the semiconductor layer, and comprising a plurality of element regions and a street for defining each element region; a laser grouping step of removing the wiring layer in the street by irradiating a laser beam, and forming an opening where the semiconductor layer is exposed in the street; and a step of etching the semiconductor layer exposed to the opening. The laser grouping step comprises: a first irradiation step of irradiating the laser beam along the street; a direction change step of changing a direction in a spot-shaped substrate surface of the laser beam after the first irradiation step; and a second irradiation step of irradiating the laser beam again along the street after the direction change step.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a method for manufacturing element chips, and more particularly to a method for dividing a substrate having a semiconductor layer into individual chips by dicing. [Background technology]

[0002] A method has been proposed for dicing a semiconductor wafer containing multiple integrated circuits by forming a protective layer over the semiconductor wafer to cover the integrated circuits, patterning gaps in the protective layer to form a mask, and etching the semiconductor wafer through the gaps.

[0003] Patent document 1 discloses a method for dicing a substrate containing multiple ICs, comprising the steps of forming a mask on the substrate to cover and protect the ICs, the mask including a layer of water-soluble material in contact with the top surfaces of the ICs, patterning the mask by a laser scribing process to provide a patterned mask having gaps to expose areas of the substrate between the ICs, and plasma etching the substrate through the gaps in the patterned mask to singulate the ICs. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Special Publication No. 2014-523112 Summary of the Invention [Problem to be solved by the invention]

[0005] In recent years, a method has been developed for manufacturing element chips by dicing a substrate having a wiring layer and a semiconductor layer, in which groove-shaped openings (gaps) are formed in divided areas of the wiring layer called streets, and plasma is applied to the semiconductor layer exposed from the openings to etch the semiconductor layer.

[0006] When laser light is irradiated along a street (division area) to form a groove by laser scribing, the cross-sectional shape of the groove may become asymmetric due to the influence of factors such as the shape of the irradiated laser beam, dirt on optical components, and misalignment of the optical axis. [Means for solving the problem]

[0007] In view of the above, one aspect of the present invention relates to a method for manufacturing an element chip, comprising: a step of preparing a substrate including a semiconductor layer having a first main surface and a second main surface, and a wiring layer formed on the first main surface side of the semiconductor layer, the substrate including a plurality of element regions and a plurality of streets defining the element regions; a laser grooving step of irradiating the substrate placed on a stage with laser light from the first main surface side to remove the wiring layer in the streets and form openings through which the semiconductor layer is exposed on the streets; and a step of etching the semiconductor layer exposed in the openings, the plurality of streets including first streets, the laser grooving step comprising: (i) a first irradiation step of irradiating the laser light along the first streets; (ii) a direction changing step of changing a direction of the spot shape of the laser light within the first main surface after the first irradiation step; and (iii) a second irradiation step of irradiating the laser light again along the first streets after the direction changing step. Effect of the Invention

[0008] According to the present invention, it is possible to prevent the groove shape formed on the semiconductor layer by laser processing from becoming asymmetric, thereby enabling high-quality processing. [Brief description of the drawings]

[0009] [Figure 1] 1 is a flowchart illustrating a method for manufacturing a component chip according to an embodiment of the present disclosure. [Diagram 2] 1A to 1C are cross-sectional views illustrating process steps of a manufacturing method for a component chip according to an embodiment of the present disclosure. [Diagram 3]1 is a top view that typically illustrates a state of a substrate placed on a stage in a manufacturing method for a component chip according to an embodiment of the present disclosure. FIG. [Figure 4] 1 is a top view of a substrate with an enlarged area of ​​a street to be irradiated with laser light in a manufacturing method of a component chip according to an embodiment of the present disclosure. FIG. [Diagram 5] FIG. 1 is a conceptual diagram showing a configuration of an example of an apparatus for outputting laser light. [Figure 6] FIG. 1 is a conceptual diagram of an example of a plasma processing apparatus used in a dicing process. [Figure 7] FIG. 2A is a top view showing a transport carrier supporting a substrate, and FIG. 2B is a cross-sectional view taken along line YY. [Figure 8] 1A and 1B are diagrams illustrating an example of intensity distribution in an irradiation spot of laser light. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] A method for manufacturing a component chip according to an embodiment of the present disclosure includes a step of preparing a substrate including a semiconductor layer having a first main surface and a second main surface, and a wiring layer formed on the first main surface side of the semiconductor layer. The substrate includes a plurality of element regions and streets that define the element regions. The wiring layer may include a circuit layer and a resin layer that protects a surface of the circuit layer. Typically, the circuit layer includes a metal material, and the resin layer includes a resin material.

[0011] The streets defining the multiple element regions are provided in a line shape in a predetermined pattern on the first main surface side of the substrate. The multiple streets include at least a first street. The first street extends in a line shape on the first main surface, for example, along a first direction. The multiple streets may include a second street extending on the first main surface along a second direction intersecting the first direction. The first streets and the second streets can divide the substrate into multiple element regions.

[0012] The semiconductor layer is made of, for example, silicon (Si), gallium arsenide (GaAs), gallium nitride (GaN), silicon carbide (SiC), or the like.

[0013] The wiring layer usually includes a circuit layer and a resin layer that protects the surface of the circuit layer. The circuit layer includes, for example, a low-k (low dielectric constant) material, a copper (Cu) wiring layer, a metal material, an insulating film (silicon dioxide, silicon nitride, etc.), lithium tantalate (LiTaO3), lithium niobate (LiNbO3), etc. The resin layer includes, for example, a thermosetting resin such as polyimide, a photoresist such as phenol resin, a water-soluble resist such as acrylic resin, etc.

[0014] The manufacturing method of the element chip further includes a laser grooving step of irradiating the substrate placed on the stage with a laser beam from the first main surface side to remove the wiring layer in the streets and form openings that expose the semiconductor layer in the streets, and a step of etching the semiconductor layer exposed in the openings. The laser grooving step is also called a scribing step or a laser scribing step.

[0015] The openings are usually formed in a groove shape along the linear street. The width direction of the street is synonymous with the width direction of the opening (gap) formed in a groove shape, and is a direction perpendicular to the length direction of the street. From the viewpoint of effective use of the substrate, the narrower the groove opening width, the easier it is to narrow the opening width as the verticality of the side surfaces of the wiring layer on both sides of the opening improves.

[0016] The laser grooving process includes: (i) a first irradiation process of irradiating laser light along a first street; (ii) a direction changing process of changing the direction of the spot shape of the laser light within the first main surface after the first irradiation process; and (iii) a second irradiation process of irradiating the laser light again along the first street after the direction changing process.

[0017] First, in the first irradiation step (i), a laser beam is irradiated onto the wiring layer along the first street to form a groove. The laser beam may be irradiated multiple times along the first street. At this time, the direction of the spot shape of the laser beam irradiated onto the substrate in the first main surface of the substrate (also referred to as the "spot shape direction" in this specification) depends on the settings of the laser irradiation device and the relative positional relationship between the substrate and the laser irradiation device. The spot shape and the spot shape direction are usually constant in multiple laser irradiations along the first street and are maintained at a predetermined setting value.

[0018] However, due to misalignment of the optical axis of the laser irradiation device (due to movement of the device, for example) or dirt on the optical components, the beam intensity distribution or spot shape at the irradiation spot may deviate from the set value. This may result in an asymmetric distribution of the beam intensity of the laser light in the width direction of the street, and an asymmetric cross-sectional shape of the groove that is formed. For example, one sidewall of the groove may be formed steeper than the other, resulting in a difference in the verticality of the sidewalls. In this case, debris may easily adhere to the less steep (less vertical) sidewall, which may make it difficult to proceed with the etching of the semiconductor layer that is performed after the laser grooving process.

[0019] Fig. 8 shows an example of the intensity distribution in the irradiation spot of the laser light. In Fig. 8, the laser beam is decentered, and the intensity distribution of the laser light has a peak where the intensity is maximum at a position shifted from the center of the beam. In the case of Fig. 8, the direction of the spot shape of the laser light is defined as the -X direction.

[0020] After the first irradiation step (i), in the direction change step (ii), the direction of the spot shape of the laser light in the first main surface is changed. Then, in the second irradiation step (iii), the laser light is irradiated again to the wiring layer along the first street with the spot shape in a changed direction. This widens the groove formed in the first irradiation step (i), and processes the groove having an asymmetric cross-sectional shape formed in the first irradiation step (i) into a more symmetric cross-sectional shape, thereby making it possible to prevent etching of the semiconductor layer in a state where the cross-sectional shape of the groove is asymmetric.

[0021] The first street has a width. The position of the laser light in the first irradiation step (i) may be different from the position of the laser light in the second irradiation step (iii) in the width direction of the first street. For example, the laser light in the first irradiation step may be irradiated along a first planned irradiation line set within the width of the first street, and the laser light in the second irradiation step may be irradiated along a second planned irradiation line set within the width of the first street. The first planned irradiation line and the second planned irradiation line extend at different positions within the width of the first street. The first planned irradiation line and the second planned irradiation line each extend at a position deviated from the center line of the first street, and extend along the edges at both ends in the width direction of the first street.

[0022] In the direction changing step (ii), the direction of the spot shape of the laser light may be changed by rotating the substrate relative to the laser irradiation device, or by rotating the laser irradiation device relative to the substrate, but it can be easily changed by rotating the substrate. Usually, the substrate is fixed to the stage by a method such as vacuum suction. The direction of the spot shape of the laser light can be easily changed by rotating the stage to which the substrate is fixed together with the substrate.

[0023] Similarly, the irradiation of laser light along the first street in the first irradiation step (i) and the second irradiation step (iii) may be performed while moving a laser irradiation device along the extension direction of the first street, or while moving a substrate (or a stage to which the substrate is fixed) along the extension direction of the first street. However, it is preferable to move the substrate along the extension direction of the first street, as this can be easily performed.

[0024] In the direction changing step (ii), the stage may be rotated by 180° to rotate the direction of the spot shape. In this case, in the first irradiation step (i) and the second irradiation step (iii), the laser light may be irradiated while moving the stage along the same direction (the extension direction of the first street). Note that "moving along the same direction" means that the moving direction of the stage in the first irradiation step (i) is parallel or anti-parallel to the moving direction of the stage in the second irradiation step (iii), and includes the case where the moving directions are 180° opposite.

[0025] After the second irradiation step (iii), the direction of the spot shape of the laser light may be changed again, and then the first irradiation step (i) may be repeated.

[0026] In the laser grooving step, the first irradiation step and the second irradiation step may be repeated multiple times. After the first irradiation step and before the start of the second irradiation step, and after the second irradiation step and before the start of the first irradiation step, a direction change step of changing the direction of the spot shape of the laser light may be performed. The direction of the spot shape of the laser light may be changed by the direction change step so that the direction is maintained in a first state in the first irradiation step and in a second state in the second irradiation step.

[0027] After the laser grooving process, a process of singulating the substrate is carried out. In the singulation process, the semiconductor layer exposed in the formed grooves (openings) is etched until it reaches the second main surface. Since the element regions of the semiconductor layer are masked by the wiring layer, the streets of the semiconductor layer exposed from the openings are etched. As a result, the substrate is divided into a plurality of element chips each having an element region.

[0028] The etching method is not particularly limited as long as it can etch and remove the semiconductor layer. The etching may be plasma etching. Etching may be performed by the so-called Bosch process, which repeats a protective film deposition step of forming a protective film on at least the sidewall of a groove formed in a substrate, a protective film removal step of removing the protective film deposited on the bottom of the groove in the substrate, and a step of etching the bottom of the groove in the substrate in this order.

[0029] According to the method for manufacturing an element chip according to an embodiment of the present disclosure, in the laser grooving process, the sidewalls of the groove are machined to be nearly vertical and have a highly symmetrical cross-sectional shape, so that etching of the semiconductor layer exposed in the groove in the depth direction can be performed with high precision, and the substrate can be easily singulated into a plurality of element chips.

[0030] Fig. 1 is a flow chart showing a method for manufacturing an element chip according to an embodiment of the present disclosure. Fig. 2(a)-(d) are cross-sectional views showing steps of the method for manufacturing an element chip according to an embodiment of the present disclosure, showing cross-sectional views of a substrate at a street in each of steps (i)-(iii) of the preparation step and the laser grooving step. Fig. 3(a)-(c) are schematic views showing a substrate placed on a stage from above in each of steps (i)-(iii) of the laser grooving step, corresponding to Fig. 2(b)-(d), respectively.

[0031] (preparation process) First, as shown in FIG. 2(a), a substrate 10 is prepared (preparation step). The substrate 10 is placed on a stage of a processing device. The substrate 10 may be provided with a notch or a part of a circle cut out into a shape having corners to indicate the orientation of the substrate relative to the processing device. The substrate 10 may be fixed to a transport carrier composed of a frame and a support member that supports the substrate 10. The substrate 10 may be placed on the stage by placing the transport carrier on the stage. In this case, the notch indicating the orientation of the substrate may be provided on the transport carrier side (see FIG. 7).

[0032] The substrate 10 includes a semiconductor layer 11 having a first main surface 11A and a second main surface 11B, and a wiring layer 12 formed on the first main surface 11A side of the semiconductor layer 11. The wiring layer 12 includes, for example, a circuit layer 13a and a resin layer 13b that protects the circuit layer. The substrate 10 includes a plurality of element regions R D and a plurality of element regions R D Each of the lines is a street R S are separated by

[0033] (1st irradiation step) Next, as shown in FIG. 2(b), the first laser beam is directed to the street R S to form the grooves 14 (first irradiation step). The irradiation of the first laser light can be performed multiple times until the semiconductor layer 11 is exposed at the bottom of the grooves 14. The first laser light may be a laser beam having a Gaussian distribution, or may be a laser beam having a top hat distribution.

[0034] A laser beam having a top hat distribution is a laser beam having a substantially constant beam intensity within a predetermined distance range from the center of the beam. The intensity at the end of the top hat distribution (the shoulder portion where the intensity starts to drop sharply) is not significantly different from the central intensity, and is, for example, 90% to 98% of the central intensity. For beam shaping into a top hat distribution, known techniques such as a diffractive optical element (DOE) or an aspheric beam shaper can be used.

[0035] The first laser beam is directed to a street R shown in FIG. S The first laser light is irradiated along the direction in which the street R extends. S The first laser light can be emitted along the

[0036] Due to misalignment of the optical axis in the laser irradiation device, dirt on the optical components, etc., the orientation of the spot shape of the first laser light on the substrate 10 may deviate from the set value. As a result, the beam intensity of the first laser light may be reduced by the street R. S In the example shown in FIG. 2(b), one side wall 14a of the groove 14 is formed steeper than the other side wall 14b, and the street R S There is a difference in the perpendicularity of the side walls at both ends in the width direction.

[0037] (Direction change process) Next, the direction of the spot shape of the laser light in the first principal surface is changed. The direction of the spot shape can be changed by rotating the stage on which the substrate 10 is placed. In this case, as shown in FIG. 2(c), the substrate 10 is rotated 180°, so that the left and right of the cross-sectional shape of the substrate 10 are reversed. In the top view of the substrate 10 as viewed from above, as shown in FIG. 3(b), the position of the notch is rotated 180° from FIG. 3(a).

[0038] (Second irradiation process) Next, as shown in FIG. 2(d), the second laser beam is directed to the street R. S The second laser beam is irradiated again (second irradiation step). The irradiation of the second laser beam can be performed multiple times, similar to the first laser beam. The second laser beam may be a laser beam having a Gaussian distribution or a laser beam having a top hat distribution. The second laser beam may be a beam having the same intensity distribution as the first laser beam.

[0039] The second laser beam is, like the first laser beam, directed to the street R shown in FIG. S The first laser light is irradiated along the direction in which the street R extends. S However, the second laser beam can be emitted along the street R. S The direction in which the second laser light is irradiated along the axis may be a bottom-to-top direction as shown in FIG. 3(c), or may be a top-to-bottom direction opposite to that in FIG. 3(c).

[0040] The irradiation of the second laser light widens the groove 14, forming an opening 15 that exposes the semiconductor layer. Even if the intensity distribution of the first laser light is asymmetric and the cross-sectional shape of the formed groove 14 is asymmetric, as shown in the cross-sectional view of Fig. 2(d), opening 15 having a bilaterally symmetrical cross-sectional shape can be formed.

[0041] FIG. 4 shows a street R on the upper surface of the substrate 10 where the first laser light and the second laser light are irradiated. S In the first irradiation step, the first laser light is irradiated onto the street R. S In the second irradiation step, the second laser light is irradiated along the first irradiation planned line L1 in the street R. S The first irradiation planned line and the second irradiation planned line are aligned along the street R S The first irradiation planned line and the second irradiation planned line are respectively extended from the center line of the street R. S One and the other of both edge portions in the width direction of the opening 15 are stretched. In this case, since the laser is irradiated to different regions in the first irradiation step and the second irradiation step, it is possible to efficiently form a wide opening 15 with a small number of laser irradiations. In addition, it is easy to form a wide opening 15 having steep (almost vertical) sidewalls.

[0042] Next, an apparatus for performing the laser grooving process will be described. The laser light used in the laser grooving process can be obtained, for example, by using an optical system as shown in FIG. 5. The optical system in FIG. 5 includes a laser oscillator 301, a beam expander 302, a cylindrical lens 303 having a semicircular cross section, a bend mirror 304, a DOE 305, and a condenser lens 306. The laser light L having a Gaussian distribution in all directions output from the laser oscillator 301 is incident on the beam expander 302 having a collimating function. The beam expander 302 adjusts the beam diameter of the laser light L to an appropriate value corresponding to the DOE 305 into which the laser light transmitted through the cylindrical lens 303 is incident. The laser light L having a circular beam spot output from the beam expander 302 is converted into an ellipse by passing through the cylindrical lens 303, and is incident on the bend mirror 304. The DOE 305 converts the spot shape of the laser light into a rectangle. The converted laser light enters condenser lens 306 and is then irradiated onto substrate 10. The spot diameter of the laser light emitted from condenser lens 306 is condensed to, for example, 35 μm or less (preferably 20 μm or less) in the width direction of the divided regions, and is irradiated onto the substrate (wiring layer) that is the workpiece.

[0043] The DOE 305 can be provided with a function for converting the spot shape of the laser light into an arbitrary shape. The DOE can also be provided with a function for converting a beam intensity distribution having a Gaussian distribution into a top-hat distribution.

[0044] The laser oscillator 301 is a pulsed laser oscillator that oscillates a pulsed laser beam, and the mechanism for oscillating the laser beam L in a pulse waveform is not particularly limited. Examples include a method of turning the beam output on and off with a mechanical shutter, a method of pulse-controlling the excitation source of the laser beam L, and a method of switching the beam output. The laser oscillation mechanism of the laser oscillator 301 is also not particularly limited, and examples thereof include a semiconductor laser that uses a semiconductor as a medium for laser oscillation, a gas laser that uses a gas such as carbon dioxide (CO2) as a medium, a solid-state laser that uses YAG or the like, a fiber laser, and the like. Furthermore, solid-state lasers include wavelength-converted green lasers and ultraviolet lasers.

[0045] The pulse width of the laser light irradiated to the substrate 10 is not particularly limited, but is preferably 500 nanoseconds or less, and more preferably 200 nanoseconds or less, in order to reduce thermal effects. The wavelength of the laser light is also not particularly limited, but is preferably in the ultraviolet range (wavelength 200 to 400 nm) or a relatively short wavelength visible range (wavelength 400 to 550 nm), in order to increase absorption of the laser light by the substrate 10. The oscillation frequency of the laser light is also not particularly limited, but is, for example, 1 to 200 kHz, and the higher the frequency, the faster the processing becomes possible.

[0046] Next, a plasma processing apparatus used in the singulation step will be described with reference to Fig. 6. However, the plasma processing apparatus is not limited to this. From the viewpoint of handling, the singulation step is preferably performed in a state in which the substrate 10 is supported by a support member 22 as shown in FIG. 7. At this time, the second main surface 11B side of the semiconductor layer 11 of the substrate 10 is abutted against the support member 22. The material of the support member 22 is not particularly limited. In particular, considering that the substrate 10 is diced in a state in which it is supported by the support member 22, the support member 22 is preferably a flexible resin film so that the element chip 10x can be easily picked up. At this time, from the viewpoint of handling, the support member 22 is fixed to the frame 21. Hereinafter, the frame 21 and the support member 22 fixed to the frame 21 are collectively referred to as the transport carrier 20. FIG. 7 is a top view (a) and a cross-sectional view (b) taken along the line YY showing the transport carrier 20 and the substrate 10 supported by the support member 22. The support member 22 has, for example, a surface having an adhesive (adhesive surface 22a) and a surface not having an adhesive (non-adhesive surface 22b). The frame 21 may be provided with notches 21a and corner cuts 21b for positioning.

[0047] The plasma processing apparatus 200 includes a vacuum chamber 203 and a stage 211 in the processing space inside the vacuum chamber 203. The vacuum chamber 203 is provided with a gas inlet 203a and an exhaust port 203b. A process gas source 212 and an ashing gas source 213 are connected to the gas inlet 203a. A decompression mechanism 214 including a vacuum pump that exhausts gas in the vacuum chamber 203 to reduce the pressure is connected to the exhaust port 203b.

[0048] The substrate 10 held by the transport carrier 20 is placed on the stage 211. A plurality of supports 222 that are raised and lowered by a lifting mechanism 223A are arranged on the outer periphery of the stage 211. The transport carrier 20 that has been brought into the vacuum chamber 203 is transferred to the supports 222 and mounted on the stage 211.

[0049] A cover 224 is disposed above the stage 211, which covers at least the frame 21 of the transport carrier 20 and has a window 224W through which the substrate 10 is exposed. The cover 224 is connected to a plurality of lifting rods 221, and is driven to move up and down by a lifting mechanism 223B. The top of the vacuum chamber 203 is closed by a dielectric member 208, and an antenna 209 is disposed above the dielectric member 208 as an upper electrode. The antenna 209 is connected to a first high frequency power source 210A.

[0050] The stage 211 includes an electrode layer 215, a metal layer 216, and a base 217 arranged in this order from above, which are surrounded by an outer periphery 218, and a protective outer periphery ring 229 is arranged on the upper surface of the outer periphery 218. An electrode section for electrostatic attraction (ESC electrode) 219 and a high frequency electrode section 220 connected to a second high frequency power supply 210B are arranged inside the electrode layer 215. The ESC electrode 219 is connected to a DC power supply 226. By applying high frequency power to the high frequency electrode section 220, the etching process can be performed while applying a bias voltage. A coolant flow path 227 for cooling the stage 211 is formed in the metal layer 216, and a coolant is circulated by a coolant circulation device 225.

[0051] The control device 228 controls the operation of the plasma processing device 200, which includes the first high frequency power supply 210A, the second high frequency power supply 210B, the process gas source 212, the ashing gas source 213, the pressure reduction mechanism 214, the refrigerant circulator 225, the lifting mechanism 223A, the lifting mechanism 223B, and the electrostatic adsorption mechanism.

[0052] The plasma is generated under conditions that allow the semiconductor layer 11 of the substrate 10 to be etched. The above etching conditions can be appropriately selected depending on the material of the semiconductor layer 11. When the semiconductor layer 11 is made of Si, the street R of the semiconductor layer 11 is S The so-called Bosch process can be used for the etching. In the Bosch process, a protective film deposition step, a protective film etching step, and a Si etching step are sequentially repeated to dig each groove in the depth direction, and the street is etched perpendicularly to the depth direction. In generating plasma, multiple types of source gases may be used in combination. In this case, multiple types of source gases may be introduced into the vacuum chamber 203 with a time difference, or multiple types of source gases may be mixed and introduced into the vacuum chamber 203.

[0053] In this manner, the substrate 10 is divided into a plurality of element chips 10x each having an element region Rx while being supported by the support member 22. After completion of the singulation process, the plurality of element chips 10x supported by the support member 22 are sent to a pick-up process. In the pick-up process, the plurality of element chips 10x are peeled off from the support member 22, respectively.

[0054] After the singulation step, the resin film remaining on the element chips 10x may be removed by ashing or cleaning. [Industrial Applicability]

[0055] According to the method for producing element chips of the present invention, high-quality plasma dicing can be performed, and therefore it is useful as a method for producing element chips from various substrates. [Explanation of symbols]

[0056] 10: Substrate 10x: Element chip 11: Semiconductor layer 11A: 1st main surface 11B: 2nd main surface 12: Wiring layer 13a:Circuit layer 13b: Resin layer 14: Groove 15:Aperture 20: Transport carrier 21: Frame 21a:Notch 21b: Corner cut 22: Support member 22a:Adhesive side 22b: Non-adhesive side 200: Plasma processing equipment 203: Vacuum chamber 203a: Gas inlet 203b: Exhaust port 208: Dielectric material 209: Antenna 210A: 1st high frequency power supply 210B: 2nd high frequency power supply 211: Stage 212: Process gas source 213: Ashing gas source 214: Pressure reducing mechanism 215: Electrode layer 216: Metal layer 217: Foundation 218: Outer periphery 219:ESC electrode 220: High frequency electrode section 221: Lifting rod 222: Support part 223A, 223B: Lifting mechanism 224: Cover 224W: Window 225: Refrigerant circulation device 226: DC power supply 227: Coolant flow path 228: Control device 229: Outer ring 301: Laser oscillator 302: Beam expander 303: Cylindrical lens 304: Bend mirror 305:DOE 306: Condenser lens R D : Element area R S : Street (Divided Area)

Claims

1. A step of preparing a substrate including a semiconductor layer having a first main surface and a second main surface, and a wiring layer formed on the first main surface side of the semiconductor layer, the substrate including a plurality of element regions and a plurality of streets defining the element regions; a laser grooving step of irradiating the substrate placed on a stage with a laser beam from the first main surface side to remove the wiring layer in the streets and form openings in the streets through which the semiconductor layer is exposed; and etching the semiconductor layer exposed in the opening. the plurality of streets includes a first street; The laser grooving process includes: (i) a first irradiation step of irradiating the laser light along the first street; (ii) a direction changing step of changing a direction of the spot shape of the laser light within the first principal surface after the first irradiation step; (iii) a second irradiation step of irradiating the laser light again along the first street after the direction changing step.

2. the first street has a width; the irradiation of the laser light in the first irradiation step is performed along a first planned irradiation line that is set within the width of the first street, the irradiation of the laser light in the second irradiation step is performed along a second planned irradiation line that is set within the width of the first street, The method for manufacturing an element chip according to claim 1 , wherein the first planned irradiation line and the second planned irradiation line are different.

3. 3. The method for manufacturing a component chip according to claim 1, wherein in said direction changing step, the direction of the spot shape of the laser light is changed by rotating the stage.

4. In the direction changing step, the stage rotates 180°, 4. The method for manufacturing a component chip according to claim 3, wherein in the first irradiation step and the second irradiation step, the irradiation of the laser light along the first street is performed by moving the stage in the same direction relative to the laser light.

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