Manufacturing method of element chip and manufacturing method of junction structure

Abstract

To obtain an element chip with a flat surface.SOLUTION: The manufacturing method of an element chip includes steps of: preparing a circuit board 1 including a first layer 2, a second layer 3, and a split area; flattening the top surface of the second layer 3; forming a boundary 6 between the second layer 3 and a protective layer 4 by forming the protective layer 4 on the flattened top surface; forming a groove 5 that reaches the first layer 2 in the split area by removing the protective layer 4 and the second layer 3 in the split area by irradiation with laser light, and depositing a sediment D containing the composition of the protective layer 4 and the second layer 3 on the side wall of the groove 5 to cover at least the boundary 6; exposing boundary 6 on the side wall by removing the sediment D; and consequently dividing the circuit board 1 into multiple element chips by exposing the groove 5 to plasma to etch the first layer 2.SELECTED DRAWING: Figure 6

Description

[Technical field]

[0001] The present disclosure relates to a method for manufacturing an element chip and a method for manufacturing a bonded body. [Background technology]

[0002] Conventionally, a technique for manufacturing a plurality of element chips by plasma dicing a substrate is known (for example, Patent Document 1). The manufacturing method of element chips in Patent Document 1 includes the steps of preparing a substrate having a plurality of element regions and division regions that define the element regions, forming a mask layer on the upper surface of the substrate, removing the mask layer corresponding to the division regions by irradiating with laser light, and exposing the division regions of the substrate to plasma to obtain a plurality of element chips corresponding to the element regions. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2005-191039 A Summary of the Invention [Problem to be solved by the invention]

[0004] In recent years, the development of so-called hybrid bonding technology, which directly bonds the surfaces of element chips to each other, or the surfaces of element chips to each other, has been progressing. While the hybrid bonding technology is advantageous in that it can shorten the bonding distance, it is required that the surfaces of element chips and the like are highly flat. In this situation, one of the objectives of the present disclosure is to obtain an element chip with a flat surface. [Means for solving the problem]

[0005] One aspect of the present disclosure relates to a method for manufacturing an element chip, the method including a preparation step of preparing a substrate having a first layer, a semiconductor layer, and a second layer, the first layer being formed on the first surface side of the first layer and including an insulator, the substrate having a plurality of element regions and division regions that define the element regions, a planarization step of polishing the first surface side of the substrate to planarize an upper surface of the second layer, a protection layer formation step of forming a boundary between the second layer and the protection layer by forming a protection layer on the planarized upper surface, and a step of irradiating the division regions with a laser beam from the first surface side to remove the protection layer and the second layer in the division regions, thereby forming a pre-etched region. The method includes a laser grooving step of forming a groove in the dividing region, the groove penetrating the protective layer and the second layer and reaching the first layer, and depositing a deposit containing a composition of the protective layer and the second layer removed by the irradiation of the laser light on a side wall of the groove so as to cover at least the boundary; a deposit removal step of removing the deposit to expose the boundary on the side wall; and a plasma dicing step of exposing the groove to plasma to etch the first layer while the second main surface is supported by a support member after the deposit removal step, thereby dividing the substrate into a plurality of element chips each having the element region.

[0006] Another aspect of the present disclosure relates to a method for manufacturing a bonded body, the method comprising: an element chip preparation step of preparing an element chip; a second substrate preparation step of preparing a second substrate; and a bonding step of bonding the element chip to the second substrate, the element chip preparation step including a step of preparing a first substrate having a first main surface and a second main surface, a first layer being a semiconductor layer, and a second layer formed on the first main surface side of the first layer and including an insulator, the first substrate including a plurality of element regions and division regions defining the element regions; a planarization step of polishing the first main surface side of the first substrate to planarize an upper surface of the second layer; a protection layer formation step of forming a boundary between the second layer and the protection layer by forming a protection layer on the planarized upper surface; and a step of irradiating the division regions with a laser beam from the first main surface side to remove the protection layer and the second layer in the division regions. a laser grooving process for forming a groove in the dividing region that penetrates the protective layer and the second layer and reaches the first layer, and depositing a deposit containing a composition of the protective layer and the second layer removed by the irradiation of the laser light on a side wall of the groove so as to cover at least the boundary; a deposit removing process for exposing the boundary on the side wall by removing the deposit; a plasma dicing process for exposing the groove to plasma to etch the first layer while the second main surface is supported by a support member after the deposit removing process, thereby dividing the first substrate into a plurality of element chips each having an element region; and a protective layer removing process for removing the protective layer after the plasma dicing process, wherein in the bonding process, the first main surface side of the element chip is bonded to the second substrate in close contact with the second substrate. Effect of the Invention

[0007] According to the present disclosure, a component chip having a flat surface can be obtained. [Brief description of the drawings]

[0008] [Figure 1] FIG. 2 is a cross-sectional view for explaining a preparation step, showing an example of a first substrate. [Diagram 2]FIG. 4 is a cross-sectional view for illustrating a planarizing step, in which the first main surface of the first substrate is planarized. [Diagram 3] FIG. 11 is a cross-sectional view for explaining a protective layer forming step, in which a protective layer is formed on an upper surface of a second layer. [Figure 4] FIG. 2 is a cross-sectional view for explaining a laser grooving process, in which a groove is formed and a deposit is formed on the side surface of the groove. [Diagram 5] FIG. 13 is a cross-sectional view illustrating a first removal step in the deposit removal process, in which deposits mainly on the bottom surface of the groove are removed. [Figure 6] FIG. 13 is a cross-sectional view illustrating a second removal step of the deposit removal process, in which deposits are mainly removed around the boundary. [Figure 7] FIG. 2 is a cross-sectional view for explaining a plasma dicing process, in which a plurality of element chips are shown. [Figure 8] FIG. 11 is a cross-sectional view for explaining a protective layer removing step, in which the protective layer has been removed. [Figure 9] FIG. 11 is a cross-sectional view for explaining a second substrate preparation step and a bonding step, showing a state in which the element chip is bonded to the second substrate. [Figure 10] FIG. 1 is a schematic diagram illustrating an example of a plasma processing apparatus. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] The following will describe an embodiment of the manufacturing method of the element chip and the manufacturing method of the bonded body according to the present disclosure. However, the present disclosure is not limited to the examples described below. In the following description, specific numerical values ​​and materials may be exemplified, but other numerical values ​​and materials may be applied as long as the effects of the present disclosure are obtained.

[0010] (Method of manufacturing element chip) The method for manufacturing an element chip according to the present disclosure is a method for obtaining a plurality of element chips by singulating a substrate by plasma etching. The method for manufacturing an element chip according to the present disclosure includes a preparation step, a planarization step, a protective layer formation step, a laser grooving step, a deposit removal step, and a plasma dicing step.

[0011] In the preparation step, a substrate having a first main surface and a second main surface is prepared, the substrate including a first layer which is a semiconductor layer and a second layer which is formed on the first main surface side of the first layer and includes an insulator. The substrate includes a plurality of element regions and a division region which defines the element regions. The first layer and the second layer may be adjacent to each other. The semiconductor material included in the first layer is not particularly limited, and may be, for example, Si, SiC, GaN, or GaAs. The second layer may include, for example, an insulating film such as SiO2, SiN, or SiCN, and a metal such as Cu or Al. The shape of each element region is not particularly limited, and may be, for example, a rectangle, a polygon, or a circle. The width of the division region is also not particularly limited, and may be appropriately set according to the purpose.

[0012] In the planarization step, the first main surface side of the substrate is polished to planarize the upper surface of the second layer. In the planarization step, the upper surface of the second layer may be planarized by, for example, chemical mechanical polishing (CMP). The upper surface (or the outermost surface) of the second layer may include SiO2 or SiON.

[0013] In the protective layer forming step, a protective layer is formed on the flattened upper surface of the second layer to form a boundary between the second layer and the protective layer. The protective layer may contain a water-soluble or water-insoluble resin material. The thickness of the protective layer is not particularly limited, and may be such that it is not completely removed in the plasma dicing step. As the water-insoluble resin material, for example, a photoresist material can be exemplified.

[0014] In the laser grooving step, the division region is irradiated with laser light from the first main surface side to remove the protective layer and the second layer in the division region. As a result, a groove is formed in the division region that penetrates the protective layer and the second layer and reaches the first layer, and a deposit (or debris) containing the composition of the protective layer and the second layer removed by the irradiation of the laser light is deposited on the side wall of the groove so as to cover at least the boundary. The laser light may be an ultrashort pulse laser light on the picosecond or femtosecond order, but from the viewpoint of manufacturing costs, it is preferable that the laser light be a short pulse laser light on the nanometer order. The laser light may be absorbed by the protective layer and the second layer, but may not be absorbed by the first layer.

[0015] As a result of intensive research, it was discovered that the deposits covering the boundary between the second layer and the protective layer and its vicinity contribute to the formation of minute protrusions (or burrs) on the surface of the device chip obtained later. Such minute protrusions often have a size of several tens to several hundreds of nanometers, and can be a factor that hinders interfacial bonding in hybrid bonding.

[0016] In contrast, in the deposit removal step, the deposit is removed to expose the boundary on the side wall of the groove. The deposit may be removed by plasma treatment. In this way, by removing the deposit at the boundary between the second layer and the protective layer and in the vicinity thereof, it is possible to suppress the formation of minute protrusions on the surface of the element chip obtained later.

[0017] In the plasma dicing step, after the deposit removal step, the grooves are exposed to plasma to etch the first layer while the second main surface is supported by a support member, thereby dividing the substrate into a plurality of device chips each having a device region. The plasma etching can be performed using the protective layer as a mask. The Bosch process can be used to etch the first layer. The support member can have an annular frame and a holding sheet attached to the frame and to which the substrate is attached. As described above, the device chip obtained later has almost no minute protrusions formed on its surface. Or, even if minute protrusions are formed on the surface of the device chip, their size is several nm or less, and they are unlikely to interfere with interfacial bonding in hybrid bonding.

[0018] The deposit removal process may be performed by exposing a substrate placed on a stage of a plasma processing apparatus equipped with a stage capable of applying high-frequency power to plasma, and may include a first removal step performed with a first high-frequency power applied to the stage, and a second removal step performed after the first removal step with a second high-frequency power applied to the stage. The second high-frequency power may be greater than the first high-frequency power. For example, the first high-frequency power may be 20 W or more and 100 W or less, and the second high-frequency power may be 150 W or more and 600 W or less.

[0019] The first removal step may be performed by a first plasma generated while supplying a first raw material gas containing fluorocarbon and oxygen. The second removal step may be performed by a second plasma generated while supplying a second raw material gas containing fluorocarbon, oxygen, and a rare gas. The ratio of the rare gas contained in the second raw material gas may be greater than the ratio of the rare gas contained in the first raw material gas. The first raw material gas may not contain a rare gas. The second removal step is performed by a second plasma generated while supplying a second raw material gas containing a relatively large amount of rare gas in a state in which a relatively large second high frequency power is applied to the stage. Therefore, the deposits on the sidewall of the groove are effectively removed by the sputtering action, and the boundary between the second layer and the protective layer is easily exposed.

[0020] The deposit removal step may be performed by using plasma capable of etching the protective layer and the second layer. For example, plasma generated while supplying a raw material gas containing fluorocarbon, oxygen, and a rare gas may be used as the plasma capable of etching the protective layer and the second layer. The raw material gas may further contain SF6. The deposit removal step may expand the width of the groove at the boundary between the second layer and the protective layer. The groove width at the boundary refers to the width of the groove at the position of the boundary in the depth direction of the groove. The groove width may be expanded by 50 nm or more and 2000 nm or less before and after the deposit removal step.

[0021] The groove formed in the laser grooving process may have an inclined shape that narrows toward the bottom surface. The deposit removal process may reduce the inclination angle of the side surface of the groove at the boundary between the second layer and the protective layer. The inclination angle of the side surface of the groove at the boundary refers to the acute angle formed by the tangent of the side surface of the groove at the boundary and the plane on which the boundary exists. The inclination angle may be 65° or more and 90° or less before the deposit removal process, and may be 60° or more and 88° or less after the deposit removal process.

[0022] The protective layer may contain a water-soluble resin. In this case, it is possible to reduce the environmental impact in the manufacture of the element chip. Examples of the water-soluble resin include polyvinyl acetate or its saponification products (partially saponified polyvinyl acetate, polyvinyl alcohol, etc.), polyacrylic acid, polymethacrylic acid, polyacrylamide, 2-acrylamido-2-methylpropanesulfonic acid, polyvinylpyrrolidone, polystyrenesulfonic acid, polyethylene oxide, water-soluble polyester, oxazole-based water-soluble polymer (oxazole-2-ethyl-4,5-dihydro homopolymer, etc.), or salts thereof (alkali metal salts, ammonium salts, etc.).

[0023] The manufacturing method of the element chip may further include a protective layer removal step of removing the protective layer by contacting the protective layer with a cleaning liquid containing water (e.g., water) after the plasma dicing step. When removing the protective layer, if deposits remain at the boundary between the second layer and the protective layer, the above-mentioned minute protrusions of several tens to several hundreds of nm may be formed on the surface of the element chip. However, since the manufacturing method of the element chip according to the present disclosure includes the above-mentioned deposit removal step, such minute protrusions are hardly formed, or even if they are formed, they can be limited to a size of several nm.

[0024] (Method of Manufacturing Joint) The method for producing a bonded body according to the present disclosure is a method for producing a bonded body by bonding an element chip obtained by dividing a substrate by plasma etching to a second substrate. The method for producing a bonded body according to the present disclosure includes an element chip preparation step, a second substrate preparation step, and a bonding step.

[0025] The element chip preparation step includes a preparation step, a planarization step, a protective layer formation step, a laser grooving step, a deposit removal step, and a plasma dicing step, similar to the element chip manufacturing method according to the present disclosure, and further includes a protective layer removal step. Each step other than the protective layer removal step may be performed similarly to each step in the element chip manufacturing method according to the present disclosure, by replacing the "substrate" with a "first substrate". In the protective layer removal step, the protective layer is removed after the plasma dicing step. At that time, the deposit removal step can prevent minute protrusions of several tens to several hundreds of nm from being formed on the surface of the element chip. The surface of the element chip may be subjected to a hydrophilization treatment using plasma.

[0026] In the second substrate preparation step, a second substrate is prepared. The surface of the second substrate may include a region made of SiO2 or SiON and a region made of a metal such as Cu or Al. The surface of the second substrate may be subjected to a hydrophilic treatment using plasma.

[0027] In the bonding step, the element chip is bonded to the second substrate. In the bonding step, the first main surface side of the element chip is closely attached to the second substrate and bonded. The bonding step may be performed by hybrid bonding. Since there are no minute protrusions of several tens to several hundreds of nanometers on the surface of the element chip, the bonding can be performed well.

[0028] The deposit removal process is performed by exposing a substrate placed on a stage of a plasma processing apparatus equipped with a stage capable of applying high-frequency power to plasma, and may include a first removal step performed with a first high-frequency power applied to the stage, and a second removal step performed after the first removal step with a second high-frequency power applied to the stage.

[0029] The first removal step may be performed by a first plasma generated while supplying a first source gas containing fluorocarbon and oxygen. The second removal step may be performed by a second plasma generated while supplying a second source gas containing fluorocarbon, oxygen and a rare gas. The ratio of the rare gas contained in the second source gas may be greater than the ratio of the rare gas contained in the first source gas.

[0030] The deposit removal step may be performed by a plasma capable of etching the protective layer and the second layer. For example, the plasma capable of etching the protective layer and the second layer may be a plasma generated while supplying a source gas containing a fluorocarbon, oxygen, and a rare gas. The source gas may further contain SF6. The deposit removal step may expand the width of the groove at the boundary between the second layer and the protective layer.

[0031] The groove formed by the laser grooving process may have a tapered shape that narrows toward the bottom surface. The deposit removal process may reduce the angle of inclination of the side surface of the groove at the interface between the second layer and the protective layer.

[0032] The protective layer may contain a water-soluble resin. Examples of the water-soluble resin include polyvinyl acetate or its saponification products (partially saponified polyvinyl acetate, polyvinyl alcohol, etc.), polyacrylic acid, polymethacrylic acid, polyacrylamide, 2-acrylamido-2-methylpropanesulfonic acid, polyvinylpyrrolidone, polystyrenesulfonic acid, polyethylene oxide, water-soluble polyester, oxazole-based water-soluble polymer (oxazole-2-ethyl-4,5-dihydro homopolymer, etc.), and salts thereof (alkali metal salts, ammonium salts, etc.).

[0033] In the protective layer removing step, the protective layer may be removed by contacting the protective layer with a cleaning liquid containing water.

[0034] As described above, according to the present disclosure, by removing the deposits in a predetermined area, it is possible to obtain a component chip having a flat surface suitable for hybrid bonding. Furthermore, according to the present disclosure, it is possible to manufacture a bonded body including such an component chip by hybrid bonding.

[0035] In the following, an example of the manufacturing method of the element chip and the manufacturing method of the bonded body according to the present disclosure will be specifically described with reference to the drawings. The above-mentioned steps can be applied to the steps of the manufacturing method of the element chip and the manufacturing method of the bonded body of the example described below. The steps of the manufacturing method of the element chip and the manufacturing method of the bonded body of the example described below can be modified based on the above description. In addition, the matters described below may be applied to the above embodiment. Among the steps of the manufacturing method of the element chip and the manufacturing method of the bonded body of the example described below, steps that are not essential to the manufacturing method of the element chip and the manufacturing method of the bonded body according to the present disclosure may be omitted. Note that the figures shown below are schematic and do not accurately reflect the shape and number of the actual members.

[0036] The method for producing a bonded body of the present embodiment is a method for producing a bonded body by bonding element chips obtained by dividing a substrate by plasma etching to a second substrate. As shown in Figs. 1 to 9, the method for producing a bonded body includes an element chip preparation step of preparing an element chip 10, a second substrate preparation step of preparing a second substrate 50, and a bonding step of bonding the element chip 10 to the second substrate 50.

[0037] The element chip preparation process is a process that can correspond to the element chip manufacturing method according to the present disclosure, and includes a preparation process, a planarization process, a protective layer formation process, a laser grooving process, a deposit removal process, a plasma dicing process, and a protective layer removal process.

[0038] In the preparation step, as shown in FIG. 1, a first substrate 1 having a first main surface 1a and a second main surface 1b is prepared, the first substrate 1 including a first layer 2 which is a semiconductor layer and a second layer 3 which is formed on the first main surface 1a side of the first layer 2 and includes an insulator. The first substrate 1 includes a plurality of element regions EA and division regions DA which define the element regions EA. In this embodiment, the upper surface (outermost surface) of the second layer 3 includes SiO2, but is not limited thereto. At least one metal electrode 3a is disposed in the second layer 3 corresponding to the element regions EA. At least one metal electrode 3b is disposed in the second layer 3 corresponding to the division region DA. For example, a part of the metal electrode 3a corresponding to the element regions EA protrudes from the upper surface of the second layer 3.

[0039] 2, in the planarization step, the first main surface 1a side of the first substrate 1 is polished to planarize the upper surface of the second layer 3. In this embodiment, the upper surface of the second layer 3 is planarized by CMP, but the present invention is not limited to this.

[0040] In the protective layer forming step, as shown in Fig. 3, a protective layer 4 is formed on the upper surface of the flattened second layer 3 to form a boundary 6 between the second layer 3 and the protective layer 4. The protective layer 4 in this embodiment contains a water-soluble resin, but is not limited thereto. The protective layer forming step and subsequent steps may be performed in a state in which the second main surface 1b of the first substrate 1 is supported by a support member 20 (for example, a resin holding sheet).

[0041] In the laser grooving process, as shown in Fig. 4, a laser beam (not shown) is irradiated onto the dividing region DA from the first main surface 1a side to remove the protective layer 4 and the second layer 3 in the dividing region DA. As a result, a groove 5 is formed in the dividing region DA, penetrating the protective layer 4 and the second layer 3 and reaching the first layer 2, and a deposit D containing the composition of the protective layer 4 and the second layer 3 removed by the irradiation of the laser beam is deposited on the side wall of the groove 5 so as to cover at least the boundary 6. In this embodiment, the deposit D is deposited over almost the entire side wall of the groove 5. The groove 5 formed in the laser grooving process has an inclined shape so as to become narrower toward the bottom surface (toward the bottom in Fig. 4).

[0042] In addition, although a minute protrusion is illustrated near the boundary 6 in Fig. 4, this is for the sake of convenience in promoting understanding of the technical content of the present disclosure. That is, such a minute protrusion is formed as a result on the surface of the element chip after the protective layer 4 is removed in the conventional manufacturing method, and it is presumed that it is formed by a part of the deposit D that has accumulated around the boundary 6 remaining. That is, it is presumed that the minute protrusion is part of the deposit D in the state of Fig. 4, and does not exist clearly as such.

[0043] In the deposit removal process, as shown in FIGS. 5 and 6, by removing the deposit D, the boundary 6 is exposed on the side wall of the groove 5. The deposit removal process is performed by exposing the first substrate 1 placed on the stage 35 of a plasma processing apparatus 30 (described later) having a stage capable of applying high-frequency power to the plasma, and is performed in a state where the first high-frequency power is applied to the stage 35. It includes a first removal step (which may correspond to a conventional debris cleaning process), and a second removal step performed after the first removal step in a state where second high-frequency power greater than the first high-frequency power is applied to the stage 35. The first removal step is performed by the first plasma generated while supplying a first source gas containing carbon fluoride and oxygen, and the second removal step is performed by the second plasma generated while supplying a second source gas containing carbon fluoride, oxygen, and a rare gas (for example, Ar). The ratio of the rare gas contained in the second source gas is larger than the ratio of the rare gas contained in the first source gas. The second plasma is an example of a plasma capable of etching the protective layer 4 and the second layer 3. As shown in FIGS. 5 and 6, by the deposit removal process, the width of the groove 5 at the boundary 6 is expanded (W1 < W2), and the inclination angle of the side surface of the groove 5 at the boundary 6 becomes smaller (θ1 > θ2).

[0044] In the plasma dicing process, as shown in FIG. 7, after the deposit removal process, with the second main surface 1b supported by the support member 20, the groove 5 is exposed to the plasma to etch the first layer 2, thereby dividing the first substrate 1 into a plurality of element chips 10 including the element region EA.

[0045] In the protective layer removal process, as shown in FIG. 8, after the plasma dicing process, the protective layer 4 is removed. In the protective layer removal process of the present embodiment, the protective layer 4 is removed by bringing the protective layer 4 into contact with a cleaning liquid containing water (for example, water), but it is not limited thereto. In the protective layer removal process, the deposit D remaining on the surface of the protective layer 4 can be removed together with the protective layer 4.

[0046] The second substrate 50 prepared in the second substrate preparation step may include a semiconductor layer 51 and a wiring layer 52 including an insulator and provided on the upper surface of the semiconductor layer 51. An insulator (e.g., SiO2) and a metal electrode 52a are exposed on the outermost surface of the wiring layer 52.

[0047] In the bonding step, as shown in Fig. 9, the first main surface 1a of the element chip 10 prepared in the element chip preparation step is bonded to the second substrate 50 prepared in the second substrate preparation step in close contact with each other. At this time, since there are no protrusions of several tens to several hundreds of nanometers on the first main surface 1a of the element chip 10, the bonding can be performed well. Prior to the bonding step, it is preferable to subject the first main surface 1a of the element chip 10 and the surface of the second substrate 50 to a hydrophilic treatment using plasma or the like.

[0048] In the deposit removal step and the plasma dicing step, a plasma processing apparatus 30 (plasma etching apparatus 30) shown in FIG. 10 may be used. The plasma processing apparatus 30 includes a chamber 31 having a dielectric window at the top thereof and defining a processing chamber 34, an antenna 32 as an upper electrode provided on the upper side of the chamber 31, a first high frequency power supply 33 electrically connected to the antenna 32, a stage 35 as a lower electrode provided on the bottom side of the processing chamber 34 and on which the first substrate 1 is placed, and a second high frequency power supply 36 electrically connected to the stage 35. A gas inlet 37 provided in the chamber 31 is fluidly connected to a raw material gas source 38. An exhaust port 39 provided in the chamber 31 is fluidly connected to a vacuum exhaust unit 40 including a vacuum pump.

[0049] 10, after the first substrate 1 is placed on the stage 35, the processing chamber 34 is depressurized by the vacuum exhaust unit 40, and a raw material gas is supplied from a raw material gas source 38 to the processing chamber 34. Then, high frequency power is supplied from the first high frequency power supply 33 to the antenna 32, plasma is generated in the processing chamber 34, and the first substrate 1 is irradiated with the plasma. The first layer 2 exposed at the bottom of the groove 5 can be removed by the physicochemical action of radicals and ions in the plasma. It is possible to control the collision speed of the radicals and ions with the first substrate 1 by supplying high frequency power from the second high frequency power supply 36 to the stage 35.

[0050] The processing conditions in the deposit removal step are, for example, as follows. SF6 is supplied to the chamber 31 at 5 sccm to 50 sccm, C4F8 is supplied to the chamber 31 at 5 sccm to 50 sccm, Ar is supplied to the chamber 31 at 40 sccm to 500 sccm, and O2 is supplied to the chamber 31 at 5 sccm to 50 sccm. The pressure in the chamber 31 is 1 Pa to 5 Pa, the high frequency power applied to the antenna 32 is 1500 W to 5000 W, and the high frequency power applied to the stage 35 is 100 W to 1000 W. The processing time is 20 seconds to 180 seconds. In the processing conditions in this example, SF6 and C4F8 are used as the fluorine-containing gas, but CF4 may be used.

[0051] The deposit removal process may include a first removal step and a second removal step. The processing conditions for the first removal step are, for example, as follows: CF4 is supplied to the chamber 31 at 50 sccm or more and 200 sccm or less as process gas, and O2 is supplied to the chamber 31 at 50 sccm or more and 200 sccm or less as process gas. The pressure in the chamber 31 is 3 Pa or more and 8 Pa or less, the high frequency power applied to the antenna 32 is 1500 W or more and 5000 W or less, and the high frequency power applied to the stage 35 is 20 W or more and 100 W or less. The processing time is 30 seconds or more and 120 seconds or less. The processing conditions for the second removal step are, for example, as follows: Ar is supplied to the chamber 31 at 200 sccm or more and 400 sccm or less as process gas, CF4 is supplied to the chamber 31 at 30 sccm or more and 120 sccm or less, and O2 is supplied to the chamber 31 at 15 sccm or more and 60 sccm or less as process gas. The pressure inside the chamber 31 is 1 Pa or more and 5 Pa or less, the high frequency power applied to the antenna 32 is 1500 W or more and 4000 W or less, and the high frequency power applied to the stage 35 is 150 W or more and 600 W or less. The processing time is 15 seconds or more and 60 seconds or less.

[0052] The plasma dicing process may be performed by repeating a protective film deposition step, a protective film removal step, and a substrate etching step multiple times. The processing conditions in the protective film deposition step are, for example, as follows. C4F8 is supplied to the chamber 31 as a process gas at 150 sccm or more and 600 sccm or less. The pressure in the chamber 31 is 8 Pa or more and 16 Pa or less, the high frequency power applied to the antenna 32 is 2000 W or more and 8000 W or less, and the high frequency power applied to the stage 35 is 15 W or more and 80 W or less. The processing time is 1 second or more and 5 seconds or less. The processing conditions in the protective film removal step are, for example, as follows. SF6 is supplied to the chamber 31 as a process gas at 200 sccm or more and 800 sccm or less. The pressure in the chamber 31 is 4 Pa ​​or more and 12 Pa or less, the high frequency power applied to the antenna 32 is 2000 W or more and 8000 W or less, and the high frequency power applied to the stage 35 is 150 W or more and 600 W or less. The processing time is 1 second or more and 5 seconds or less. The processing conditions in the substrate etching step are, for example, as follows. SF6 is supplied to the chamber 31 as a process gas at 200 sccm or more and 800 sccm or less. The pressure in the chamber 31 is 20 Pa or more and 40 Pa or less, the high frequency power applied to the antenna 32 is 2500 W or more and 10000 W or less, and the high frequency power applied to the stage 35 is 20 W or more and 100 W or less. The processing time is 2 seconds or more and 10 seconds or less. The number of times that the protective film deposition step, the protective film removal step, and the substrate etching step are repeated is, for example, 20 times or more and 50 times or less.

[0053] Additional Notes The above description of the embodiments discloses the following techniques. (Technology 1) a preparation step of preparing a substrate having a first main surface and a second main surface, the substrate comprising a first layer which is a semiconductor layer, and a second layer which is formed on the first main surface side of the first layer and includes an insulator, the substrate comprising a plurality of element regions and division regions which define the element regions; a planarization step of planarizing an upper surface of the second layer by polishing the first main surface side of the substrate; a protective layer forming step of forming a protective layer on the planarized upper surface to form a boundary between the second layer and the protective layer; a laser grooving process in which a laser beam is irradiated onto the division region from the first main surface side to remove the protective layer and the second layer in the division region, thereby forming a groove in the division region that penetrates the protective layer and the second layer and reaches the first layer, and a deposit containing a composition of the protective layer and the second layer removed by the irradiation of the laser beam is deposited on a side wall of the groove so as to cover at least the boundary; a deposit removal step of removing the deposit to expose the boundary on the side wall; a plasma dicing step of exposing the groove to plasma to etch the first layer while the second main surface is supported by a support member after the deposit removing step, thereby dividing the substrate into a plurality of element chips each having the element region; A method for manufacturing an element chip comprising the steps of: (Technology 2) The deposit removal step is performed by exposing the substrate placed on a stage of a plasma processing apparatus equipped with a stage to which high frequency power can be applied to plasma, and includes a first removal step performed in a state in which a first high frequency power is applied to the stage, and a second removal step performed after the first removal step in a state in which a second high frequency power is applied to the stage, The manufacturing method of the element chip according to technique 1, wherein the second high frequency power is greater than the first high frequency power. (Technology 3) The first removal step is performed by a first plasma generated while supplying a first source gas containing fluorocarbon and oxygen; the second removal step is performed by a second plasma generated while supplying a second source gas containing a carbon fluoride, oxygen, and a rare gas; The method for manufacturing an element chip according to technique 2, wherein a ratio of the rare gas contained in the second source gas is greater than a ratio of the rare gas contained in the first source gas. (Technology 4) the deposit removal step is performed with plasma capable of etching the protective layer and the second layer; 4. The method for producing an element chip according to any one of Techniques 1 to 3, wherein the width of the groove at the boundary is expanded by the deposit removing step. (Technology 5) The groove formed in the laser grooving process has an inclined shape that narrows toward a bottom surface, 5. The method for producing a component chip according to any one of Techniques 1 to 4, wherein the inclination angle of the side surface of the groove at the boundary is reduced by the deposit removing step. (Technology 6) 6. The method for producing an element chip according to any one of Techniques 1 to 5, wherein the protective layer contains a water-soluble resin. (Technology 7) The method for producing a component chip according to technique 6, further comprising a protective layer removing step of removing the protective layer by contacting the protective layer with a cleaning solution containing water after the plasma dicing step. (Technology 8) an element chip preparation step of preparing an element chip; a second substrate preparation step of preparing a second substrate; a bonding step of bonding the element chip to the second substrate; Equipped with The element chip preparation step includes: a preparation step of preparing a first substrate including a first layer that is a semiconductor layer and a second layer that is formed on the first layer at the first main surface side and includes an insulator, the first substrate including a plurality of element regions and division regions that define the element regions; a planarization step of planarizing an upper surface of the second layer by polishing the first main surface side of the first substrate; a protective layer forming step of forming a protective layer on the planarized upper surface to form a boundary between the second layer and the protective layer; a laser grooving process in which a laser beam is irradiated onto the division region from the first main surface side to remove the protective layer and the second layer in the division region, thereby forming a groove in the division region that penetrates the protective layer and the second layer and reaches the first layer, and a deposit containing a composition of the protective layer and the second layer removed by the irradiation of the laser beam is deposited on a side wall of the groove so as to cover at least the boundary; a deposit removal step of removing the deposit to expose the boundary on the side wall; a plasma dicing step of exposing the groove to plasma to etch the first layer while the second main surface is supported by a support member after the deposit removing step, thereby dividing the first substrate into a plurality of the element chips each having the element region; a protective layer removing step of removing the protective layer after the plasma dicing step; having In the bonding step, the first main surface side of the element chip is bonded to the second substrate in close contact therewith. (Technology 9) the deposit removal step is performed by exposing the first substrate placed on a stage of a plasma processing apparatus equipped with a stage to which high frequency power can be applied to plasma, the deposit removal step including a first removal step performed in a state in which a first high frequency power is applied to the stage, and a second removal step performed after the first removal step in a state in which a second high frequency power is applied to the stage; The method for producing a bonded body according to technique 8, wherein the second high frequency power is greater than the first high frequency power. (Technology 10) The first removal step is performed by a first plasma generated while supplying a first source gas containing fluorocarbon and oxygen; the second removal step is performed by a second plasma generated while supplying a second source gas containing a carbon fluoride, oxygen, and a rare gas; The method for producing a bonded body according to technique 9, wherein a ratio of the rare gas contained in the second source gas is greater than a ratio of the rare gas contained in the first source gas. (Technology 11) the deposit removal step is performed with plasma capable of etching the protective layer and the second layer; 11. The method for producing a bonded body according to any one of Techniques 8 to 10, wherein the width of the groove at the boundary is expanded by the deposit removing step. (Technology 12) The groove formed in the laser grooving process has an inclined shape that narrows toward a bottom surface, 12. The method for producing a bonded body according to any one of Techniques 8 to 11, wherein the deposit removing step reduces an inclination angle of the side surface of the groove at the boundary. (Technology 13) 13. The method for producing a bonded body according to any one of Techniques 8 to 12, wherein the protective layer contains a water-soluble resin. (Technology 14) The method for producing a bonded body according to technique 13, wherein in the protective layer removing step, the protective layer is removed by contacting the protective layer with a cleaning liquid containing water. [Industrial Applicability]

[0054] The present disclosure can be used in a method for manufacturing an element chip and a method for manufacturing a bonded body. [Explanation of symbols]

[0055] 1: First board 1a: First main surface 1b: Second main surface 2: 1st layer 3:Second layer 3a: Metal electrode 3b: Metal electrode 4:Protective layer 5: Groove 6: Boundary 10: Element chip 20: Support member 30: Plasma processing equipment 31: Chamber 32: Antenna 33: 1st high frequency power supply 34: Processing room 35: Stage 36:Second high frequency power supply 37: Gas inlet 38: Raw gas source 39: Exhaust port 40: Vacuum exhaust section 50: Second board 51: Semiconductor layer 52: Wiring layer 52a: Metal electrode D: Deposit DA:Divided area EA: Element area W1, W2: groove width θ1, θ2: Incline angle of groove side

Claims

1. a preparation step of preparing a substrate having a first main surface and a second main surface, the substrate comprising a first layer which is a semiconductor layer, and a second layer which is formed on the first main surface side of the first layer and includes an insulator, the substrate comprising a plurality of element regions and division regions which define the element regions; a planarization step of planarizing an upper surface of the second layer by polishing the first main surface side of the substrate; a protective layer forming step of forming a protective layer on the planarized upper surface to form an interface between the second layer and the protective layer; a laser grooving process in which a laser beam is irradiated onto the division region from the first main surface side to remove the protective layer and the second layer in the division region, thereby forming a groove in the division region that penetrates the protective layer and the second layer and reaches the first layer, and a deposit containing a composition of the protective layer and the second layer removed by the irradiation of the laser beam is deposited on a side wall of the groove so as to cover at least the boundary; a deposit removal step of removing the deposit to expose the boundary on the side wall; a plasma dicing step of exposing the groove to plasma to etch the first layer while the second main surface is supported by a support member after the deposit removing step, thereby dividing the substrate into a plurality of element chips each having the element region; A method for manufacturing an element chip comprising the steps of:

2. The deposit removal step is performed by exposing the substrate placed on a stage of a plasma processing apparatus equipped with a stage to which high frequency power can be applied to plasma, and includes a first removal step performed in a state in which a first high frequency power is applied to the stage, and a second removal step performed after the first removal step in a state in which a second high frequency power is applied to the stage, The method for manufacturing an element chip according to claim 1 , wherein the second high frequency power is greater than the first high frequency power.

3. The first removal step is performed by a first plasma generated while supplying a first source gas containing fluorocarbon and oxygen, the second removal step is performed by a second plasma generated while supplying a second source gas containing a carbon fluoride, oxygen, and a rare gas; 3. The method for manufacturing an element chip according to claim 2, wherein a ratio of said rare gas contained in said second source gas is greater than a ratio of said rare gas contained in said first source gas.

4. the deposit removal step is performed with plasma capable of etching the protective layer and the second layer; The method for manufacturing an element chip according to claim 1 , wherein the width of the groove at the boundary is expanded by the deposit removal step.

5. The groove formed in the laser grooving process has an inclined shape that narrows toward a bottom surface, The method for manufacturing an element chip according to claim 1 , wherein the inclination angle of the side surface of the groove at the boundary is reduced by the deposit removing step.

6. 6. The method for manufacturing an element chip according to claim 1, wherein the protective layer contains a water-soluble resin.

7. 7. The method for producing a component chip according to claim 6, further comprising, after said plasma dicing step, a protective layer removing step of removing said protective layer by contacting said protective layer with a cleaning liquid containing water.

8. an element chip preparation step of preparing an element chip; a second substrate preparation step of preparing a second substrate; a bonding step of bonding the element chip to the second substrate; Equipped with The element chip preparation step includes: a preparation step of preparing a first substrate including a first layer that is a semiconductor layer and a second layer that is formed on the first layer at the first main surface side and includes an insulator, the first substrate including a plurality of element regions and division regions that define the element regions; a planarization step of planarizing an upper surface of the second layer by polishing the first main surface side of the first substrate; a protective layer forming step of forming a protective layer on the planarized upper surface to form an interface between the second layer and the protective layer; a laser grooving process in which a laser beam is irradiated onto the division region from the first main surface side to remove the protective layer and the second layer in the division region, thereby forming a groove in the division region that penetrates the protective layer and the second layer and reaches the first layer, and a deposit containing a composition of the protective layer and the second layer removed by the irradiation of the laser beam is deposited on a side wall of the groove so as to cover at least the boundary; a deposit removal step of removing the deposit to expose the boundary on the side wall; a plasma dicing step of exposing the grooves to plasma to etch the first layer while the second main surface is supported by a support member after the deposit removing step, thereby dividing the first substrate into a plurality of the element chips each having the element region; a protective layer removing step of removing the protective layer after the plasma dicing step; having In the bonding step, the first main surface side of the element chip is bonded to the second substrate in close contact therewith.

9. The deposit removal step is performed by exposing the first substrate placed on a stage of a plasma processing apparatus equipped with a stage to which high frequency power can be applied to plasma, and includes a first removal step performed in a state in which a first high frequency power is applied to the stage, and a second removal step performed after the first removal step in a state in which a second high frequency power is applied to the stage, The method for producing a bonded body according to claim 8 , wherein the second high frequency power is greater than the first high frequency power.

10. The first removal step is performed by a first plasma generated while supplying a first source gas containing fluorocarbon and oxygen, the second removal step is performed by a second plasma generated while supplying a second source gas containing a carbon fluoride, oxygen, and a rare gas; The method for producing a bonded body according to claim 9 , wherein a ratio of the rare gas contained in the second source gas is greater than a ratio of the rare gas contained in the first source gas.

11. the deposit removal step is performed with plasma capable of etching the protective layer and the second layer; The method for manufacturing a joint body according to claim 8 , wherein the width of the groove at the boundary is expanded by the deposit removal step.

12. The groove formed in the laser grooving process has an inclined shape that narrows toward a bottom surface, The method for manufacturing a joint body according to claim 8 , wherein the inclination angle of the side surface of the groove at the boundary is reduced by the deposit removing step.

13. The method for producing a bonded body according to any one of claims 8 to 12, wherein the protective layer contains a water-soluble resin.

14. The method for producing a bonded body according to claim 13 , wherein in the protective layer removing step, the protective layer is removed by contacting the protective layer with a cleaning liquid containing water.

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