TWI816340B - Workpiece separation device and workpiece separation method - Google Patents

Abstract

A workpiece separation device that prevents smoky or soot-like decomposition products generated due to modification of the separation layer accompanying laser irradiation from adhering to the irradiation port. The workpiece separation device is characterized by having: an optical system for irradiating laser light toward the separation layer; an optical path for the laser light from the optical system toward the workpiece; and a partition provided in the middle of the optical path, and the partition has an irradiation path formed in the optical system. The air flow layer between the port and the reforming space where the separation layer is arranged.

Description

Workpiece separation device and workpiece separation method

The present invention relates to a workpiece separation device for peeling off a workpiece during a manufacturing process of a workpiece that becomes a product such as a semiconductor wafer processing step, and a workpiece separation method using the workpiece separation device.

Conventionally, as such a workpiece separation device and workpiece separation method, a workpiece in which a crystal layer is formed on a substrate is irradiated with pulsed laser light through the substrate, thereby peeling off the crystal layer from the substrate at the interface between the substrate and the crystal layer. Laser peeling method and laser peeling device (for example, see Patent Document 1). The laser peeling device is equipped with: a laser source that generates pulsed laser light; a laser optical system for shaping the laser light into a prescribed shape; a workpiece stage for placing the workpiece; and a conveyor-like conveyor for transporting the workpiece stage. mechanism; and a control part that controls the irradiation interval of laser light generated by the laser source and the operation of the transmission mechanism, etc. The laser optical system includes: a cylindrical lens; a mirror that reflects the laser light toward the workpiece; a mask that shapes the laser light into a prescribed shape; and a lens that projects the image of the laser light that passes through the mask onto the workpiece. Projection lens. The pulsed laser light generated by the laser source passes through the substrate and is irradiated to the interface between the substrate and the material layer, whereby GaN near the interface with the substrate of the material layer is decomposed, and the material layer is peeled off from the substrate. [Prior technical literature] [Patent Document]

[Patent Document 1] Japanese Patent Application Publication No. 2012-024783

[Problem to be solved by the invention]

However, in Patent Document 1, as the material layer (separation layer) is modified by irradiation with laser light, the GaN bond is decomposed near the interface between the substrate and the material layer, so a smoky or soot-like decomposition product is generated, and the GaN bond is decomposed near the interface between the substrate and the material layer. The end face of the workpiece is released into the atmospheric space. This causes the light smoke-like or soot-like decomposition products to rise and approach the laser optical system and adhere to the projection lens. Smoke-like or soot-like decomposition products attached to the projection lens hinder laser irradiation, so the energy required for the separation layer cannot be achieved, and stable modification of the separation layer cannot be obtained. Therefore, there is a problem that it cannot be modified to the extent that the separation layer can be peeled off uniformly, causing uneven peeling and causing abnormalities in the subsequent production process. Furthermore, there is a problem that energy is absorbed by smoky or soot-like decomposition products adhering to the projection lens, and the heat of the laser optical system continues to rise, thereby causing deterioration or damage to the laser optical system. [Technical means to solve problems]

In order to solve this problem, the workpiece separation device of the present invention modifies the separation layer by irradiating the workpiece containing the separation layer with laser light. The workpiece separation device is characterized by: irradiating the laser light toward the separation layer. An optical system; an optical path of the laser light from the optical system to the workpiece; a partition provided in the middle of the optical path, the partition having an irradiation port formed in the optical system and a modification space in which the separation layer is arranged The airflow layer between parts. In order to solve this problem, the workpiece separation method of the present invention irradiates the workpiece containing the separation layer with laser light to modify the separation layer. The workpiece separation method is characterized by including: a separation step, in which the separation layer is directed from the optical system to The workpiece is provided with a partition part in the middle of the optical path of the laser light; and the laser irradiation step is to irradiate the laser light from the optical system toward the separation layer of the workpiece. In the partition step, the irradiation port and the arrangement of the laser irradiation part are The gas flow layer of the partition is formed between the reforming space portions having the separation layer, so that the irradiation port and the reforming space portion are blocked.

Hereinafter, embodiments of the present invention will be described in detail based on the drawings. As shown in FIGS. 1 to 4 , the workpiece separation device A and the workpiece separation method according to the embodiment of the present invention irradiate the workpiece W with laser light L, so that the separation layer Wb contained in the workpiece W absorbs the laser light L. A laser peeling device and a laser peeling method capable of peeling off the separation layer Wb of the workpiece W from the substrate Wa by modifying (modifying) the workpiece W. Processing for manufacturing semiconductor packages such as WLP (wafer level packaging: wafer level packaging) or PLP (panel level packaging: panel level packaging) or extremely thin semiconductor wafers (hereinafter referred to as "ultra-thin wafers") in steps.

The workpiece W is a laminated body including a transportable substrate Wa, a separation layer Wb provided on one side of the substrate Wa, and a support Wc bonded to the substrate Wa via the separation layer Wb. Furthermore, the workpiece W may be laminated to form a sealing layer (not shown) in addition to the substrate Wa, the separation layer Wb, and the support Wc so as to cover the substrate Wa, thereby airtightly protecting the substrate Wa. The substrate Wa has a circuit substrate formed into a thin plate shape from a material such as silicon and subjected to a semiconductor process such as circuit formation processing or thinning processing. The overall shape of the substrate Wa includes a rectangular (rectangular shape with right-angled corners including a rectangle and a square) panel shape, a circular wafer shape, and the like. As for the specifications of the substrate Wa, in the case of a rectangle, one side is 500 mm or more, and in the case of a circle, the diameter is 200 mm or 300 mm or more. The overall specifications in the XY direction are large, but the thickness in the Z direction is preferably thin. Also included are substrates in which the thickness of the substrate Wa is reduced to a rectangular or circular shape of, for example, 15 to 3,000 μm. In particular, when the substrate Wa has an extremely thin (hereinafter referred to as "ultra-thin") panel shape or wafer shape such as a thickness of several tens of microns, it can also be attached to a tape-shaped holding adhesive sheet such as a dicing tape. The entire surface of the substrate Wa is supported, or the substrate Wa is supported by attaching a tape-shaped holding adhesive sheet that reinforces the outer periphery with a square frame-shaped or circular frame-shaped (annular) cage such as a dicing tape.

The separation layer Wb is made of a material that has appropriate adhesion and can be modified or altered or modified in a controllable manner, and is stacked and formed sandwiched between the substrate Wa and the support Wc described below. Furthermore, the separation layer Wb is a layer that, as a method of controlling the adhesion force of the separation layer Wb, absorbs the laser light L irradiated through the substrate Wa or the support Wc and undergoes modification (modification, modification) to reduce the adhesion force. ), when exposed to slight external force, it will lose its adhesion and be modified in a way that it peels off or can be destroyed. Furthermore, the separation layer Wb is preferably one that can be easily cleaned and removed after the substrate Wa and the support Wc are peeled off. In the case shown in FIG. 1 as a specific example of the separation layer Wb, it is made of a material with sufficient adhesiveness such as polyimide resin, and the substrate Wa and the support can be detachably joined by only the separation layer Wb. Wc. Moreover, although other examples of the separation layer Wb are not shown in the figure, when the separation layer Wb is made of a material that does not have the required adhesive force, it can be changed to an auxiliary material sandwiching the adhesive layer of the separation layer Wb, and The substrate Wa and the separation layer Wb are detachably bonded using an adhesive layer.

The support Wc is a support substrate or carrier substrate that supports the substrate Wa during the thinning step of the substrate Wa, various processing steps, transfer steps, etc., thereby having the strength required to prevent damage, deformation, etc. of the substrate Wa. Therefore, the support body Wc is made of a hard rigid material and is formed in a rectangular or circular shape with specifications corresponding to the substrate Wa. Either or both of the substrate Wa or the support Wc are formed of a transparent or translucent rigid material capable of transmitting laser light L of a specific wavelength. As a specific example of the support Wc, in the case of the illustrated example, a transparent or translucent glass plate, a ceramic plate, an acrylic resin plate, etc. through which the laser light L of a specific wavelength is transmitted is used, and the thickness is set to, for example, 300 ~3,000μm.

Specifically, the workpiece separation device A according to the embodiment of the present invention mainly includes: an optical system 1 installed so as to irradiate laser light L toward the separation layer Wb of the workpiece W; and the optical system 1 is installed toward the workpiece W. The optical path 2 of the laser light L; and the partition 3 provided in the middle of the optical path 2. Furthermore, it is provided with a holding member 4 that detachably holds either the substrate Wa or the support Wc that holds the workpiece W; a suction mechanism 5 provided near the holding member 4; and a position so that the laser irradiation from the optical system 1 A driving part 6 that moves P relative to the separation layer Wb of the workpiece W; and a control part 7 configured to actuate and control the optical system 1, the partition part 3, the holding member 4, the suction mechanism 5, the driving part 6, etc. are preferred. In addition, as shown in FIG. 1 , the workpiece W is usually irradiated with laser light L in the up and down direction from the optical system 1. Hereinafter, the irradiation direction of the laser light L (light irradiation direction) is referred to as the “Z direction”. Hereinafter, the two directions intersecting the irradiation direction (Z direction) of the laser light L are referred to as “XY directions”.

The optical system 1 includes a laser light source 11 such as a laser oscillator, and a laser irradiation part 12 that guides the laser light L from the laser light source 11 to the thickness direction (Z direction) of the workpiece W. The laser irradiation unit 12 has a sweep function that moves the laser light L guided by the optical system 1 along the workpiece W in the XY direction. Thereby, the laser light L guided by the optical system 1 passes through the substrate Wa or the support Wc of the workpiece W and irradiates the entire surface of the separation layer Wb. As the laser light L irradiated from the laser irradiation part 12 toward the workpiece W, it is preferable to use a laser with a wavelength that transmits the substrate Wa or the support Wc and can be absorbed by the separation layer Wb. In particular, among the laser light L, a spot-shaped laser light L in which a high-output laser is easily obtained is more preferable than a linear (slit)-shaped laser light L in a projected shape. Compared with the continuous oscillation laser (continuous wave laser), the pulse oscillation laser light can suppress the influence of heat caused by the laser energy absorbed in the separation layer Wb and impart high energy to the separation layer Wb. (Pulse laser light) L is preferred. That is, the laser irradiation part 12 is provided with a laser scanning means (laser scanner) 12a for moving the optical axis (main axis) L1 of the point-shaped laser light L generated by the laser light source 11, and is configured to move from It is preferred that the irradiation port 12b of the laser scanner 12a scans (sweeps) the laser light L on the workpiece W in the XY direction. Therefore, it is possible to relatively move the laser light L to the separation layer Wb of the workpiece W using only the laser scanner 12a.

As shown in FIGS. 1 and 2 , the laser irradiation unit 12 includes a laser scanner 12 a that moves the optical axis L1 of point laser light L generated by the laser light source 11 along the workpiece W; and a laser scanner 12 a facing the separation layer Wb. The irradiation port 12b which guides the laser light L from the laser scanner 12a is preferable. As the laser scanner 12a, a galvano scanner, a polygon scanner, or the like is used, and the laser scanner 12a is oriented in either of the XY directions intersecting the laser irradiation direction (Z direction) from the laser scanner 12a toward the separation layer Wb or in the XY direction. Scanning from both sides is better. The irradiation port 12b is composed of a lens that condenses the laser light L from the laser scanner 12a, and an fθ lens used in combination with a galvano scanner, a polygon scanner, or the like is preferably used. The fθ lens keeps the scanning speed constant at the center part of the lens or its peripheral part, and enables the focus to be placed on a single plane. Furthermore, as the lens of the irradiation port 12b, use a non-telecentric lens that can arrange the chief ray L2 at various angles with respect to the optical axis L1 that passes through the center of the lens and is perpendicular to the lens surface, or a lens that can arrange the chief ray in parallel with the optical axis L1. The telecentric lens of L2 is better. In particular, in the case of a non-telecentric lens, it is preferable to mainly use the center portion of the lens (the center of the lens and its peripheral portion) where the irradiation of the laser light L is stable, and not use the outer peripheral end portion of the lens where the irradiation of the laser light L is unstable. In addition, when the overall specification of the workpiece W (substrate Wa) is large, the entire workpiece W (separation layer Wb) is divided into a plurality of irradiation areas R, and the plurality of irradiation areas R are aligned from the laser scanner 12a. It is preferable to irradiate point laser light L.

As a specific example of the optical system 1, in the case shown in FIGS. 1 and 2, first, the laser light L generated by the laser oscillator serving as the laser light source 11 is passed through the beam expander 13 to adjust the beam. diameter. Next, the direction of the laser light L is changed by the reflecting mirrors 14 and 15 such as the turning mirror, and is guided to the laser scanner 12a which becomes the laser irradiation part 12. Finally, the ultrashort-pulse laser light L passes through the irradiation port (lens) 12b from the laser scanner 12a, and is sequentially irradiated to the target position of the workpiece W held on the holding member 4 to scan. As an example of the laser scanner 12a and the irradiation port (lens) 12b, in the illustrated example, a galvano scanner is used as the laser scanner 12a, and the laser light L is scanned in the Y direction and reciprocated. As the lens of the irradiation port 12b, a non-telecentric lens is used. Furthermore, although not shown in the figure, as other examples, a polygon scanner can be used as the laser scanner 12a, or a combination of a current scanner and a polygon scanner, or a plurality of current scanners, or other structures can be used to perform XY scanning. Direction of both sides scanning and other changes. As the lens of the irradiation port 12b, a telecentric lens or another structure can also be used.

On the other hand, as shown in FIG. 1 , at least the workpiece W, the holding member 4 described below, the driving part 6 and the like are provided in the modification space part S1. The reforming space S1 is formed in an internal space Si of a sealed device B composed of a chamber or the like, and the workpiece W is moved from the external space S into the reforming space by a transfer means (not shown) composed of a transfer robot or the like. Part S1 is better. In this case, in the loaded workpiece W, either the substrate Wa or the support Wc is held at a predetermined position of the holding member 4, and the separation layer Wb is modified by irradiation with the laser light L. Thereafter, the substrate Wa peeled off from the support Wc due to the modification of the separation layer Wb is carried out from the modification space S1 to the external space Sо by the conveying means. Furthermore, in the internal space Si of the sealed device B, it is preferable to set at least the reforming space S1 to have a negative pressure than the external space Sо. Thereby, the modification operation of the separation layer Wb accompanied by the irradiation of the laser light L can be performed in a negative pressure atmosphere.

As the separation layer Wb of the workpiece W is modified by the irradiation of the laser light L from the irradiation port (lens) 12b, the atomic/molecular bonds are decomposed near the interface between the substrate Wa and the separation layer Wb, thereby generating smoke or The soot-like decomposition product D is released from the end surface Wd of the workpiece W (substrate Wa, separation layer Wb) into the reforming space S1. There is a risk that the relatively light smoke-like or soot-like decomposition product D may rise in the reforming space S1 and approach the optical system 1 and adhere to the exposed irradiation port (lens) 12 b and the like. The smoky or soot-like decomposition product D attached to the irradiation port (lens) 12b will hinder the laser irradiation of the separation layer Wb, making it difficult to achieve the energy required for the laser irradiation position P of the separation layer Wb, so that the laser irradiation position P of the separation layer Wb cannot be obtained. Modification of stable separation layer Wb.

Therefore, in order to solve such a problem, as shown in FIGS. 1 to 4 , a partition 3 is provided in the middle of the optical path 2 of the laser light from the laser irradiation part 12 to the workpiece W. The partition portion 3 has an air flow layer 3 a formed between the irradiation port (lens) 12 b of the laser irradiation portion 12 and the modified space portion S1 in which the separation layer Wb of the workpiece W is arranged. The air flow layer 3 a is formed on a plane intersecting the optical path 2 and transmits the laser light irradiated from the laser irradiation part 12 toward the workpiece W. However, the irradiation port (lens) 12 b of the laser irradiation part 12 is covered by the air flow layer 3 a , thereby being blocked from the reforming space S1. In addition, the partition 3 is disposed in the optical path 2 so as to cover at least the irradiation port (lens) 12 b of the laser irradiation part 12 in the vicinity of the irradiation port 12 b so that the irradiation port 12 b and the airflow layer 3 a are aligned in the Z direction. Closer is better. In detail, as a specific example of the arrangement position of the partition part 3, it is preferable to arrange it within 1/3 of the total length of the optical path 2 from the irradiation port 12b to the workpiece W. Thereby, even if the range of the airflow layer 3a is narrow, it can reliably cover the irradiation port 12b.

In addition, as the partition part 3, as shown by the two-dot chain line in FIG. 1, a partition member 3b is provided in the internal space Si of the sealing device B, and is used to separate the separation layer Wb of the workpiece W into a modified space. Part S1 and an optical system arrangement space S2 in which the laser light source 11 or the laser irradiation part 12 of the optical system 1 are arranged. In this case, it is preferable to set at least the reforming space portion S1 separated by the isolation member 3b to have a negative pressure than the external space Sо. The isolation member 3b is arranged laterally such that, in addition to the optical path 2 of the laser light from the irradiation port (lens) 12b of the laser irradiation part 12 to the workpiece W, the internal space Si of the sealing device B is divided into a modified space part S1 and an optical system arrangement Space S2. In the illustrated example, the isolation member 3b is configured in a plate shape.

Furthermore, as shown in FIGS. 1 to 3 , the partition 3 has a blowout port 31 that blows out gas toward the optical path space S3 in which the optical path 2 is formed, and an inlet that sucks in the gas blown out from the blowout port 31 toward the optical path space S3 . 32, and the blowout outlet 31 and the suction inlet 32 are preferably arranged opposite to the direction intersecting the optical path 2 (XY direction). The blowout port 31 is connected to an air supply drive source (not shown) via an air supply duct 31a, and is provided in an external space S such as a compressor, a blower, or a compression pump that blows gas such as compressed air or compressed gas toward the suction port 32. Thereby, the lightly smoky or soot-like decomposition product D that is released from the end surface Wd of the workpiece W (substrate Wa, separation layer Wb) into the reforming space S1 and rises from the optical path 2 before reaching the irradiation port (lens) 12 b. (Optical path space part S3) is blown away. However, the blower outlet 31 only has the function of blowing away the smoke-like or soot-like decomposition products D from the optical path 2. The blown smoke-like or soot-like decomposition products D may hit the wall and return to the irradiation port (lens). ) 12b, so the suction port 32 is added. The suction port 32 is connected to an exhaust driving source (not shown) provided in the external space S such as a vacuum pump or a vacuum pump via an exhaust duct 32a. Therefore, the gas blown out from the blowout port 31 is sucked by the suction port 32, thereby forming the airflow layer 3a intersecting the optical path 2. The specifications of the blowout port 31 and the suction port 32 are set to be larger than the XY direction specifications of the irradiation port (lens) 12b, and at least the shape of the blowout port 31 is along the straight line direction (in the example in the figure, the X direction) on the plane intersecting the optical path 2 It is formed in a wide width, and thereby the gas is violently ejected from the suction port 32 in the linear direction (in the illustrated example, the Y direction).

As an example of the partition part 3, in the case shown by the solid line in FIG. 3, a set (each one) of the blowout outlet 31 and the suction inlet 32 are arranged to face each other in the Y direction across the optical path 2, and form a flow in the Y direction. Airflow layer 3a. The X-direction specifications of the blowout port 31 and the suction port 32 are formed slightly larger than the X-direction specifications of the irradiation port (lens) 12b. Furthermore, as another example, although not shown in the figure, one air outlet 31 and one suction inlet 32 can be arranged to face each other in directions such as the X direction other than the Y direction. Moreover, as another example of the partition 3, as shown by the two-dot chain line in FIG. 3, a plurality of sets (in the illustrated example, 2 each, 4 in total) of the blowout outlets 31, 31' and the suction inlet. 32 and 32' are arranged to face each other on a plurality of planes different in the Z direction, and the flow direction of the air flow layer 3a formed respectively can cross the XY direction. In the illustrated example, the air supply duct 31a and the exhaust duct 32a are arranged along the isolation member 3b of the partition 3, but the arrangement of the air supply duct 31a and the exhaust duct 32a can be changed to other locations than in the illustrated example.

Furthermore, as shown in FIG. 4 , the partition 3 may only have an air intake port 33 for sucking gas from the optical path space S3 formed in the optical path 2 . It is preferable to provide a plurality of suction ports 33 so as to sandwich the direction intersecting the optical path 2 (XY direction) with the optical path 2 as the center. The suction port 33 is connected to a suction driving source (not shown) provided in the external space S such as a vacuum pump or a vacuum pump via a suction duct 33a. Therefore, gas such as compressed air or compressed gas is sucked in from the optical path space S3 through the suction port 33 , thereby forming an air flow layer 3 a intersecting the optical path 2 . The specifications of the suction port 33 are set to be larger than the XY direction specifications of the irradiation port (lens) 12b, and the shape of the suction port 33 is at least as wide as the linear direction (X direction in the example in the figure) on the plane intersecting the optical path 2 The gas is formed in a wide area, whereby the gas is violently sucked in from the suction port 33 in the linear direction (the Y direction in the illustrated example). As a modification of the partition part 3, in the case shown by the solid line in FIG. 4, a set of (two) suction ports 33 is disposed so as to face the optical path 2 and the optical path space part S3 in the Y direction, and The air flow layer 3a flowing in the Y direction is formed by the suction air from the optical path space S3. Furthermore, as another example, although not shown in the figure, a set (two) of the air intake ports 33 can be arranged to face each other in directions such as the X direction other than the Y direction. Furthermore, as another example of the partition 3, as shown by the two-dot chain line in FIG. 4, a plurality of groups (in the illustrated example, 2 each, 4 in total) of the air intake ports 33, 33' are arranged so that The air flow layer 3a flowing in the XY direction can also be formed by suction from the optical path space S3 on the same plane in the Z direction or on a plurality of planes different in the Z direction. Furthermore, as another example, although not shown in the figure, the air suction port 33 is arranged in an annular shape with the optical path 2 as the center, and can also be formed in a radial shape with the optical path 2 as the center by sucking air from the optical path space S3. The flowing air layer 3a. In the illustrated example, the air intake duct 33a or the air intake duct 33a' is arranged along the partition member 3b of the partition 3, but the arrangement of the air intake duct 33a or the air intake duct 33a' can also be changed to a location other than the illustrated example. .

The holding member 4 is composed of a rectangular or circular fixed plate that is thick enough not to be deformed by rigid bodies such as metal and has a size larger than the outer shape of the workpiece W (substrate Wa, separation layer Wb, support Wc). In the holding member 4, a holding chuck 4b for detachably holding either the base plate Wa or the support Wc of the workpiece W is provided on a smooth holding surface 4a facing the workpiece W in the thickness direction (Z direction). . Furthermore, although not shown in the figure, other examples of the holding member 4 may include a structure in which the entire workpiece W is fixed (immovably and detachably held) by a plurality of support pins instead of the smooth holding surface 4a, or a structure based on Fixed plate structure of honeycomb panel. In the case of a structure in which the workpiece W is fixed by pins, it is preferable that the workpiece W be adsorbed and fixed to a part or the entire front end of a plurality of support pins. Furthermore, it is preferable to provide the suction mechanism 5 near the holding member 4 held by the holding chuck 4b of the holding member 4. The suction mechanism 5 has a suction port 51 that faces the end surface Wd of the workpiece W in the XY direction and opens. The suction port 51 is connected to a suction driving source (not shown) provided in the external space S such as a vacuum pump or a vacuum pump via a suction duct 52 . Thereby, among the smoky or soot-like decomposition products D released from the end surface Wd of the workpiece W (substrate Wa, separation layer Wb) into the reforming space S1, the suction port 51 is mainly used to suck out the heavy smoky or soot-like decomposition products D. The soot-like decomposition products D and the like are discharged to the external space Sо.

The driving part 6 is configured as an optical axis relative movement mechanism that moves either the holding member 4 or the laser irradiation part 12 (laser scanner 12a) or the holding member 4 and the laser irradiation part 12 (laser scanner 12a). irradiating both sides of the laser scanner 12a), whereby the laser light L irradiated from the laser scanner 12a is directed at least in the same direction (Z direction) as the irradiation direction (Z direction) of the laser light L irradiated from the laser scanner 12a with respect to the workpiece W held by the holding member 4. The two crossed directions (XY direction) move relative to each other. The relative movement direction by the drive unit 6 is not limited to the XY direction, but also includes the Z direction as necessary. The optical axis relative movement mechanism used as the driving part 6 mainly includes a workpiece side movement type that moves the holding member 4 and the workpiece W, and an optical axis side movement type that moves the laser scanner 12a. As a specific example of the driving part 6, in the case of the workpiece side movement type shown in FIGS. 1 and 2, the driving part 6 is provided in the holding member 4, and the driving part 6 is used to move the holding member 4 in the X direction and the Y direction or By moving in the Z direction, the laser irradiation position P from the laser scanner 12a moves in the XY direction or the Z direction. In this case, an XY stage, an XY table, or the like is used as the drive unit 6, and has an X-axis moving mechanism 61 and a Y-axis moving mechanism 62 composed of a motor shaft or the like. Furthermore, if necessary, it is preferable to provide a Z-axis moving mechanism (not shown) for moving the holding member 4 in the Z direction. Furthermore, as another example of the workpiece side movement type, although not shown in the figure, a transfer mechanism such as a conveyor belt can be used as the drive unit 6 instead of the XY stage or XY table. In addition, in the case shown in FIGS. 1 and 2 , by the operation of the laser scanner 12 a, the irradiation surface of the separation layer Wb is divided into one irradiation area R among the plurality of irradiation areas R that is smaller than the entire irradiation surface ( In the illustrated example, the entire first irradiation area R1) is filled without gaps by the irradiation traces of a plurality of point-shaped laser lights L. Thereafter, the drive unit 6 (optical axis side movement type) is linked to repeat the alignment and irradiation of the point-shaped laser light L to the next irradiation area R (the second irradiation area R2 in the example in the figure). Finally, all the plurality of irradiation areas R are subjected to aligned irradiation. In addition, in the case of the optical axis side movement type, although not shown in the figure, the driving part 6 can be provided on only a part of the optical system 1, the holding member 4 does not move, and the laser from the laser scanner 12a can be The irradiation position P moves in the XY direction or Z direction. In this case, the drive unit 6 has an XY-axis moving mechanism composed of a galvano scanner, a polygon scanner, or the like. Furthermore, when relative movement in the Z direction is required, a Z-axis moving mechanism is provided in the holding member 4, or the laser scanner 12a is moved in the Z direction by the driving unit 6.

The control part 7 is connected to the laser light source 11 or the laser irradiation part 12 of the optical system 1, the air supply driving source, the exhaust driving source or the air suction driving source of the partition part 3, and the holding clip of the holding member 4. The drive source of the head 4b, the suction drive source of the suction mechanism 5, and the optical axis relative movement mechanism based on the drive unit 6 are electrically connected to each controller. Furthermore, in addition to the above, the control unit 7 is a conveying means for loading the workpiece W toward the holding member 4 and simultaneously transporting the peeled substrate Wa, and a peeling mechanism for pulling the peeled substrate Wa away from the support Wc after laser irradiation. (not shown), a controller that is electrically connected to the pressure reducing drive source of the sealed device B. The controller that becomes the control unit 7 follows a program preset in its control circuit (not shown) and sequentially activates control at a preset time. That is, the control unit 7 not only performs the entire actuation control of the workpiece separation device A including the on/off control of the laser light L irradiated from the laser light source 11 to the laser irradiation position P, but also performs Various settings such as settings of various parameters of the laser light L. The laser irradiation unit 12 (laser scanner 12a) or the drive unit 6 of the optical system 1 is controlled by the control unit 7 to irradiate a plurality of irradiation areas R divided into the separation layer Wb of the workpiece W held by the holding member 4. Each irradiation area R is irradiated with laser light L from the laser scanner 12a, and the irradiation angle of the laser light L is substantially perpendicular to or at a predetermined angle with the surface of the support Wc or the separation layer Wb. In addition, the controller serving as the control section 7 is configured as follows. It has an input means (not shown) such as a touch panel, a display section (not shown), etc., and can set the laser scan by operating the input means. The scanning distance of the instrument 12a, the specifications of the plurality of irradiation areas R, or the irradiation sequence of the plurality of irradiation areas R with the laser light L from the laser scanner 12a, etc.

Next, the program set in the control circuit of the control unit 7 will be described as a workpiece separation method based on the workpiece separation device A. The main steps of the workpiece separation method using the workpiece separation device A according to the embodiment of the present invention include: a holding step of detachably holding either the substrate Wa or the support Wc of the workpiece W on the holding member 4; and a separation step of A partition 3 is provided in the middle of the optical path 2 of the laser light L; and in a laser irradiation step, the laser irradiates from the other side of the substrate Wa or the support Wc of the workpiece W held on the holding member 4 toward the separation layer Wb. The portion 12 irradiates laser light L. Furthermore, it is preferable to include a relative movement step to separate the laser irradiation position P from the laser irradiation part 12 with respect to the workpiece W held on the holding member 4 as a subsequent step of the laser irradiation step. The layer Wb moves relatively; and a separation step in which either the substrate Wa or the support Wc of the workpiece W held on the holding member 4 is peeled off from the other. In addition, it is preferable to include the following steps as a subsequent step of the separation step, namely, a cleaning step using a cleaning liquid to remove the residue of the separation layer Wb remaining on the substrate Wa separated from the separation layer Wb; and a cutting step using cutting. The substrate Wa after the cleaning step is cut off.

In the holding step, the workpiece W before separation is loaded into the holding member 4 by the operation of the transfer means such as a transfer robot, and the workpiece W before separation is placed on the substrate Wa or the support at a predetermined position with respect to the holding surface 4 a of the holding member 4 Either side of the body Wc (the substrate Wa in the illustrated example) is held immovably by the holding chuck 4b. In the separation step, the air flow of the partition 3 is formed in the middle of the optical path 2 of the laser light from the laser irradiation part 12 to the workpiece W by the operation of the air supply driving source or the exhaust driving source of the partition 3 The layer 3a blocks and protects the irradiation port 12b (lens) from the reforming space S1. Furthermore, in the separation step, the suction driving source operates substantially simultaneously with the formation of the air flow layer 3a, and atomized or soot-like gas is released from the end surface Wd of the workpiece W (substrate Wa, separation layer Wb) into the reforming space S1. Among the decomposition products D, mainly heavy smoke-like or soot-like decomposition products D are sucked from the suction port 51 and discharged to the external space Sо. In addition, even a part of the rising light smoke-like or soot-like decomposition products D is inhaled from the suction port 51 , thereby reducing the total amount of the light smoke-like or soot-like decomposition products D. In addition, except for the irradiation port 12b (lens) of the laser irradiation part 12, the internal space Si of the sealing device B is separated into a modified space part S1 and an optical system arrangement space S2 by the partition member 3b. In the laser irradiation step, in the state where the air flow layer 3a is formed, by the operation of the laser light source 11 and the laser irradiation part 12 of the optical system 1, the laser light L generated by the laser light source 11 is scanned from the laser The instrument 12a passes through the other side of the substrate Wa or the support Wc of the workpiece W held on the holding member 4 (support Wc in the illustrated example) and irradiates the separation layer Wb. In the relative movement step, the workpiece W held on the holding member 4 and the laser scanner 12a move relatively in the XY direction or the Z direction due to the operation of the laser irradiation part 12 (laser scanner 12a) or the driving part 6. . In the illustrated example, alignment irradiation is performed by the operation of the laser scanner 12a or the driving unit 6, and the entire separation layer Wb is filled without gaps by the alignment irradiation.

According to the workpiece separation device A and the workpiece separation method according to this embodiment of the present invention, the air flow layer 3a of the partition 3 is provided in the middle of the optical path 2 from the optical system 1 (laser irradiation part 12) to the workpiece W, thereby optically The irradiation port 12b of the system 1 (laser irradiation part 12) and the reforming space part S1 are blocked. Therefore, in the reforming space portion S1 where the separation layer Wb is arranged, even if the decomposition product D in the form of smoke or soot is generated due to the modification of the separation layer Wb by the laser light L irradiated from the irradiation port 12 b, the decomposition product D in the form of smoke or soot is produced. The decomposition product D does not reach the irradiation port 12b from the reforming space S1. Therefore, it is possible to prevent the smoky or soot-like decomposition product D generated due to the modification of the separation layer Wb associated with laser irradiation from adhering to the irradiation port 12 b. As a result, compared with the conventional method in which smoke or soot adheres to the projection lens during peeling by irradiation with laser light, the irradiation port 12b is blocked and protected from the smoky or soot-like decomposition product D by the airflow layer 3a, and the smoky or soot-like decomposition product D is protected. Or the soot-like decomposition product D will not hinder the laser irradiation, thereby obtaining a stable modification of the separation layer Wb. Thereby, the separation layer Wb of the workpiece W can be peeled off from the substrate Wa more stably, thereby improving the processability or yield in the production process of the workpiece W. Furthermore, compared with conventional energy absorption due to smoke or soot adhering to the projection lens, the decomposition product D in the form of smoke or soot does not adhere to the irradiation port 12b, so the heat of the optical system 1 does not increase abnormally. , thereby preventing the optical system 1 from deterioration or damage. In addition, the reforming space S1 in which the separation layer Wb of the workpiece W is arranged is separated from the optical system arrangement in which the laser light source 11 or the laser irradiation part 12 of the optical system 1 is arranged by the isolation member 3 b of the partition 3 In the case of space S2, the aerosol-like or soot-like decomposition product D generated in the modified space portion S1 will not enter the optical system arrangement space S2 such as the laser irradiation portion 12, thereby preventing deterioration of lenses or optical components.

In particular, the partition 3 has a blowout port 31 for blowing out gas and an inlet 32 for sucking in the gas blown out from the blowout port 31 , and it is preferable to arrange the blowout port 31 and the suction port 32 so as to cross the optical path 2 and face each other. In this case, the gas blown out from the blowout port 31 is sucked in through the suction port 32 , thereby forming an airflow layer 3 a intersecting the optical path 2 . Therefore, even if the light smoke-like or soot-like decomposition product D generated by the modification of the separation layer Wb accompanied by the irradiation of the laser light L moves (rises) toward the irradiation port 12 b, it can move toward the irradiation port 12 b along the flow of the air flow layer 3 a. The suction port 32 guides. Thereby, all or part of the decomposition product D in the form of light smoke or soot is inhaled into the inlet 32 , so that the decomposition product D in the form of smoke or soot does not reach the irradiation port 12 b. Therefore, it is possible to reliably prevent the smoky or soot-like decomposition product D from adhering to the irradiation port 12b with a simple structure. As a result, the irradiation port 12b is blocked from the smoky or soot-like decomposition product D with high accuracy, and the separation layer Wb of the workpiece W can be more stably separated from the substrate Wa, thereby improving the workability in the production process of the workpiece W. further improvement or further improvement in yield. Furthermore, it is possible to reliably prevent the optical system 1 from being deteriorated or damaged due to the adhesion of the smoky or soot-like decomposition product D.

In addition, the partition 3 has an air suction port 33 for sucking gas from the optical path space S3 in which the optical path 2 is formed. The air suction port 33 is provided so as to sandwich the optical path 2 in the direction intersecting the optical path 2 (XY direction). Plural numbers are preferred. In this case, the air intake port 33 sucks gas from the optical path space S3 to form an air flow layer 3 a intersecting the optical path 2 . Therefore, even if the light smoke-like or soot-like decomposition product D generated by the modification of the separation layer Wb accompanied by the irradiation of the laser light L moves (rises) toward the irradiation port 12 b, it can move toward the irradiation port 12 b along the flow of the air flow layer 3 a. The suction port 33 guides. Thereby, all or a part of the light smoke-like or soot-like decomposition product D is inhaled into the air inlet 33, and the smoke-like or soot-like decomposition product D does not reach the irradiation port 12b. Therefore, it is possible to reliably prevent the smoky or soot-like decomposition product D from adhering to the irradiation port 12b with a simple structure. As a result, the irradiation port 12b is blocked from the smoky or soot-like decomposition product D with high accuracy, and the separation layer Wb of the workpiece W can be more stably separated from the substrate Wa, thereby improving the workability in the production process of the workpiece W. further improvement or further improvement in yield. Furthermore, it is possible to reliably prevent the optical system 1 from being deteriorated or damaged due to the adhesion of the smoky or soot-like decomposition product D.

Moreover, it is preferable that the partition part 3 is arrange|positioned so that it may cover at least the irradiation port 12b in the vicinity of the irradiation port 12b in the optical path 2. In this case, the air flow layer 3 a of the partition 3 is arranged in the optical path 2 in the vicinity of the irradiation port 12 b (specifically, within 1/3 of the total length of the optical path 2 from the irradiation port 12 b to the workpiece W). Even if the range of the air flow layer 3a is narrow, the irradiation port 12b can be covered with the air flow layer 3a. Therefore, the structural specifications of the partition part 3 (the air outlet 31 and the suction port 32) can be suppressed. As a result, the entire device can be made compact, thereby achieving weight reduction and cost reduction.

In addition, it is preferable to have a suction port 51 near the workpiece W that faces the end surface Wd of the workpiece W and opens. In this case, among the smoke-like or soot-like decomposition products D released from the end surface Wd of the workpiece W (substrate Wa, separation layer Wb) into the reforming space S1, the heavy smoke-like product D is mainly sucked by the suction port 51 Or soot-like decomposition product D. In addition, a part of the smoke-like or soot-like decomposition product D that rises slightly after being released from the end surface Wd is sucked together from the suction port 51 . Therefore, the total amount of the lightly smoky or soot-like decomposition products D rising toward the irradiation port 12b can be reduced. As a result, the irradiation port 12b and the smoky or soot-like decomposition product D are more accurately and reliably isolated.

Furthermore, it is preferable to set at least the reforming space S1 to have a negative pressure than the external space Sо. In this case, at least the reforming space portion S1 in which the separation layer Wb is arranged is set to a negative pressure than the space S0, so that the smoke or soot is generated due to the reformation of the separation layer Wb accompanied by the irradiation of the laser light L. The decomposition product D remains in the reforming space S1. Therefore, it is possible to prevent the aerosol-like or soot-like decomposition product D generated by the modification of the separation layer Wb from leaking from the modification space portion S1 to the external space Sо. As a result, it is possible to prevent the smoky or soot-like decomposition product D generated due to the modification of the separation layer Wb associated with laser irradiation from adversely affecting the device installed in the external space Sо.

Furthermore, in the above embodiment, the partition 3 has the blowout port 31 and the suction port 32, and the blowout port 31 and the suction port 32 are provided to face the direction (XY direction) intersecting the optical path 2. However, the present invention is not limited to this, and the partition 3 may be configured with a structure other than the illustrated example. Even in this case, the same advantages as those of the above-described embodiment can be obtained. Furthermore, in the above-described embodiment, in the illustrated example, only a panel-shaped (square) workpiece W is shown as the workpiece W. However, the workpiece W is not limited to this, and the panel-shaped (square) workpiece W may be changed to a panel-shaped (square) workpiece W. Rectangular) workpiece W or wafer-shaped (circular) workpiece W. Furthermore, in the illustrated example, the workpiece side movement type is shown in which the optical axis relative movement mechanism serving as the drive unit 6 mainly moves the workpiece W side, but the invention is not limited to this. The laser irradiation unit 12 may be used to move only the workpiece W side. An optical axis side movement type in which the drive unit 6 provided in a part of the optical system 1 moves. As a specific example, it is also possible to move the laser scanner 12a (polygon scanner or galvano scanner) of the laser irradiation unit 12 as a part of the optical system 1 in the Z direction, so that the laser irradiation area R within the same irradiation area R can be During irradiation, the holding member 4 does not move, but the laser irradiation position P from the laser scanner 12a moves in the Z direction. Furthermore, in the illustrated example, a partition member 3b is provided as the partition portion 3 in the internal space Si of the sealing device B to separate the modified space portion S1 in which the separation layer Wb of the workpiece W is arranged and the optical system arrangement space S2. , but is not limited to this, and the isolation member 3b may not be provided.

1: Optical system 2:Light path 3:Separation part 3a: Airflow layer 3b: Isolate components 4: Keep components 4a:Maintenance surface 4b: Keep the chuck 5:Suction mechanism 6:Driving department 7:Control Department 11:Laser light source 12:Laser irradiation department 12a:Laser Scanner 12a:Laser Scanner 12b: Illumination port (lens) 13: Beam expander 14:Reflector 15:Reflector 31: Blowing outlet 31a: Air supply duct 32:Suction port 32a:Exhaust duct 33: Suction port 51:Suction port 52:Suction catheter 61:X-axis moving mechanism 62: Y-axis moving mechanism A: Workpiece separation device B: closed device D: Smoke-like or soot-like decomposition products L:Laser light L1: Optical axis L2: Main light P: Laser irradiation position S1: Modification Space Department S2: Optical system configuration space S3: Optical path space department Si: internal space Sо: external space W: workpiece Wa: substrate Wb: separation layer Wc: support Wd: End face

1 is an explanatory diagram showing the overall structure of a workpiece separation device and a workpiece separation method according to an embodiment of the present invention, and is a longitudinal plan view of a separation step and a laser irradiation step. Figure 2 is a cross-sectional top view along line (2)-(2) of Figure 1. Figure 3 is a partially enlarged cross-sectional bottom view along line (3)-(3) of Figure 1. FIG. 4 is a partially enlarged cross-sectional bottom view showing a modified example of the partition part.

1: Optical system

2:Light path

3:Separation part

3a: Airflow layer

3b: Isolate components

4: Keep components

4a:Maintenance surface

4b: Keep the chuck

5:Suction mechanism

6:Driving department

7:Control Department

11:Laser light source

12:Laser irradiation department

12a:Laser Scanner

12b: Irradiation port

13: Beam expander

14:Reflector

15:Reflector

31: Blowing outlet

31a: Air supply duct

32:Suction port

32a:Exhaust duct

51:Suction port

52:Suction catheter

61:X-axis moving mechanism

62: Y-axis moving mechanism

A: Workpiece separation device

B: closed device

D: Smoke-like or soot-like decomposition products

L:Laser light

L1: Optical axis

L2: Main light

P: Laser irradiation position

S1: Modification Space Department

S2: Optical system configuration space

S3: Optical path space department

Si: internal space

So:External space

W: workpiece

Wa: substrate

Wb: separation layer

Wc: support

Wd: End face

Claims (10)

A workpiece separation device that modifies the separation layer by irradiating the workpiece containing the separation layer with laser light. The workpiece separation device is characterized by having an optical system arrangement space arranged in a sealed device and facing the separation layer. An optical system for irradiating the laser light; an optical path for the laser light from the optical system toward the workpiece in the modified space arranged in the sealed device; and a partition provided in the middle of the optical path, the partition having a An airflow layer between the irradiation port of the optical system and the modified space; and the airflow layer is formed on a plane intersecting the optical path and is disposed to cover the irradiation port, and the optical system is arranged The space is partially separated from the aforementioned modified space. The workpiece separation device according to claim 1, wherein the partition has: a blowout port for blowing out gas; and a suction port for sucking in the gas blown out from the blowout port, and the blowout port and the suction port are provided so as to be connected to the optical path Cross and oppose. The workpiece separation device according to claim 1, wherein the partition part has a suction port for sucking gas from an optical path space formed in the optical path, and the suction port is configured to sandwich the optical path in a direction intersecting with the optical path. Entering Set multiple ways. The workpiece separation device according to claim 1, claim 2, or claim 3, wherein the partition portion is disposed to cover at least the irradiation port in the vicinity of the irradiation port in the optical path. The workpiece separation device according to claim 1, claim 2, or claim 3, wherein the modified space portion has a suction port opening near the workpiece and facing an end surface of the workpiece. The workpiece separation device according to claim 4, wherein the modified space portion has a suction port opening near the workpiece and facing an end surface of the workpiece. The workpiece separation device according to claim 1, claim 2, or claim 3, wherein at least the modification space is set to have a negative pressure than the external space. The workpiece separation device according to claim 4, wherein at least the reforming space is set to have a negative pressure than the external space. The workpiece separation device according to claim 5, wherein at least the reforming space is set to have a negative pressure than the external space. A workpiece separation method that modifies the separation layer by irradiating the workpiece containing the separation layer with laser light. The feature of the workpiece separation method is that it includes: a separation step, in which the optical system configuration space is arranged in a sealed device. The optical system provides a partition in the middle of the optical path of the laser light before the workpiece is disposed in the modified space portion arranged in the sealed device; and a laser irradiation step is to irradiate the laser light from the optical system toward the separation layer of the workpiece, and In the aforementioned separation step, an airflow layer of the aforementioned separation portion is formed between the irradiation port of the laser irradiation portion and the aforementioned modified space portion on a plane intersecting the aforementioned optical path, and the aforementioned airflow layer covers the aforementioned irradiation port, so that the aforementioned The optical system arrangement space and the modification space are partitioned off.