Processing method and processing system

Abstract

To appropriately remove part or all of a first substrate in a superposed substrate in which the first substrate and a second substrate are joined to each other.SOLUTION: Provided is a processing method for processing a superimposed substrate formed by laminating a first substrate formed with a laser absorption film and a second substrate, the method including: irradiating the laser absorption film with a laser beam; locally expanding the first substrate with heat generated through the irradiation with the laser beam; and generating peeling on the boundary surface between the first substrate and the laser absorption film with a stress generated by the expansion.SELECTED DRAWING: Figure 6

Description

Technical Field

[0001] The present disclosure relates to a processing method and a processing system.

Background Art

[0002] Patent Document 1 discloses a substrate processing system having a reforming layer forming device that forms a reforming layer inside a first substrate along the boundary between the peripheral portion and the central portion of the first substrate to be removed in a polymer substrate in which a first substrate and a second substrate are joined, and a peripheral removal device that removes the peripheral portion of the first substrate with the reforming layer as a base point.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] The technology according to the present disclosure appropriately removes part or all of the first substrate in a polymer substrate in which a first substrate and a second substrate are joined.

Means for Solving the Problems

[0005] One aspect of the present disclosure is a processing method for processing a polymer substrate formed by laminating a first substrate on which a laser absorption film is formed and a second substrate, including irradiating the laser absorption film with laser light, and locally expanding the first substrate by heat generated by irradiating the laser light, and causing peeling at the interface between the first substrate and the laser absorption film due to stress generated by the expansion.

Effects of the Invention

[0006] According to the present disclosure, in a polymer substrate in which a first substrate and a second substrate are joined, part or all of the first substrate can be appropriately removed.

Brief Description of the Drawings

[0007]

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Embodiments for Carrying Out the Invention

[0008] In the manufacturing process of a semiconductor device, in a polymerized substrate in which a first substrate (a silicon substrate such as a semiconductor) having a plurality of devices such as electronic circuits formed on its surface and a second substrate are joined, the peripheral portion of the first substrate may be removed, that is, so-called edge trimming may be performed.

[0009] The edge trimming of the first substrate is performed using, for example, the substrate processing system disclosed in Patent Document 1. That is, a modified layer is formed by irradiating laser light into the first substrate, and the peripheral portion is removed from the first substrate with the modified layer as a base point. Further, according to the substrate processing system described in Patent Document 1, a modified surface or a peeling surface is formed by irradiating laser light on the interface where the first substrate and the second substrate are joined, thereby reducing the bonding force between the first substrate and the second substrate at the peripheral portion and appropriately removing the peripheral portion.

[0010] Incidentally, at the peripheral edge of the first substrate to be removed in edge trimming, there were cases where the bonding strength between the first substrate and the second substrate could not be appropriately reduced due to various factors such as the thickness and structure of the film formed at the interface between the first substrate and the second substrate. Specifically, when reducing the bonding strength between the first substrate and the second substrate, a laser beam is irradiated onto the absorption film formed at the interface to be absorbed, thereby generating stress and causing delamination at the interface between the first substrate and the second substrate. However, if the thickness or structure of the absorption film changes for each polymerized substrate processed in the substrate processing system or within the plane of the polymerized substrate processed in the substrate processing system, the amount of laser light absorbed by the absorption film changes accordingly, and there are cases where the bonding strength between the first substrate and the second substrate cannot be appropriately reduced.

[0011] However, in this regard, as a result of intensive studies by the present inventors, it was found that the stress generated at the interface when reducing the bonding strength between the first substrate and the second substrate depends on the substrate temperature during irradiation of the laser beam onto the interface. In other words, it was found that by controlling the temperature of the substrate irradiated with the laser beam, the bonding strength between the first substrate and the second substrate can be preferably reduced, and the peripheral portion of the first substrate can be removed more appropriately.

[0012] The technology according to the present disclosure has been made based on the above findings, and in a polymerized substrate in which the first substrate and the second substrate are bonded, a part or all of the first substrate is appropriately removed. Hereinafter, the wafer processing system and the wafer processing method according to the present embodiment will be described with reference to the drawings. In the present specification and the drawings, elements having substantially the same functional configuration are denoted by the same reference numerals, and redundant description is omitted.

[0013] In the wafer processing system 1 described below according to this embodiment, as shown in FIG. 1, processing is performed on a polymer wafer T that is a polymer substrate in which a first wafer W as a first substrate and a second wafer S as a second substrate are bonded. More specifically, as an example, in the polymer wafer T in which the first wafer W and the second wafer S are bonded, a peripheral portion We that is a part of the first wafer W is removed. Hereinafter, in the first wafer W, the surface on the side bonded to the second wafer S is referred to as a front surface Wa, and the surface on the side opposite to the front surface Wa is referred to as a back surface Wb. Similarly, in the second wafer S, the surface on the side bonded to the first wafer W is referred to as a front surface Sa, and the surface on the side opposite to the front surface Sa is referred to as a back surface Sb.

[0014] The first wafer W is, for example, a semiconductor wafer such as a silicon substrate, and a device layer Dw including a plurality of devices is formed on the front surface Wa side. Further, a laser absorption film Fw is formed on the device layer Dw, and the first wafer W is bonded to the second wafer S via the laser absorption film Fw. As the laser absorption film Fw, for example, an oxide film (THOX film, SiO2 film, TEOS film), SiC film, SiCN film, or an adhesive is used. Note that the peripheral portion We of the first wafer W is chamfered, and the cross section of the peripheral portion We becomes thinner toward the tip. Further, the peripheral portion We is a portion to be removed in the edge trim described later, and is, for example, in the range of 0.5 mm to 3 mm in the radial direction from the outer end portion of the first wafer W.

[0015] The second wafer S has, for example, a device layer Ds and a bonding film Fs formed on the front surface Sa, and is bonded to the first wafer W via the bonding film Fs. Further, the peripheral portion of the second wafer S is chamfered. Note that the second wafer S does not necessarily have to be a device wafer on which the device layer Ds is formed, and may be, for example, a support wafer that supports the first wafer W. In such a case, the second wafer S functions as a protective material that protects the device layer of the first wafer W.

[0016] In the illustrated example, the first wafer W is bonded to the second wafer S via the laser absorption film Fw. However, a bonding film that reduces the bonding force with the second wafer S may be formed on the surface of the first wafer W, and the bonding film may be used as the laser absorption film.

[0017] As shown in FIG. 2, the wafer processing system 1 has a configuration in which the loading / unloading station 2 and the processing station 3 are integrally connected. In the loading / unloading station 2, for example, a cassette C capable of accommodating a plurality of polymer wafers T is loaded / unloaded to / from the outside. The processing station 3 includes various processing apparatuses that perform desired processing on the polymer wafers T.

[0018] The loading / unloading station 2 is provided with a cassette mounting table 10 on which a cassette C capable of accommodating a plurality of polymer wafers T is placed. Further, on the positive X-axis side of the cassette mounting table 10, a wafer transfer device 20 is provided adjacent to the cassette mounting table 10. The wafer transfer device 20 is configured to move on a transfer path 21 extending in the Y-axis direction and is capable of transferring the polymer wafer T between the cassette C on the cassette mounting table 10 and a transition device 30 described later.

[0019] The loading / unloading station 2 is provided with a transition device 30 adjacent to the wafer transfer device 20 on the positive X-axis side of the wafer transfer device 20 for delivering the polymer wafer T between the processing station 3.

[0020] The processing station 3 is provided with a wafer transfer device 40, a surface modification device 50, an internal modification device 60, a peripheral removal device 70, and a cleaning device 80.

[0021] The wafer transfer device 40 is provided on the positive X-axis side of the transition device 30. The wafer transfer device 40 is configured to be movable on a transfer path 41 extending in the X-axis direction and is capable of transferring the polymer wafer T to the transition device 30, the surface modification device 50, the internal modification device 60, the peripheral removal device 70, and the cleaning device 80 in the loading / unloading station 2.

[0022] The interface modification device 50 irradiates a laser beam (laser beam for interface, such as a CO2 laser) onto the laser absorption film Fw formed at the interface between the first wafer W and the second wafer S, and forms an unbonded region Ae where the bonding force between the first wafer W and the second wafer S is reduced.

[0023] As shown in FIG. 3, the interface modification device 50 has a chuck 100 that holds the polymerized wafer T on its upper surface. The chuck 100 adsorbs and holds the back surface Sb of the second wafer S.

[0024] The chuck 100 is supported by a slider table 102 via an air bearing 101. A rotation mechanism 103 is provided on the lower surface side of the slider table 102. The rotation mechanism 103 incorporates, for example, a motor as a drive source. The chuck 100 is configured to be rotatable about the θ-axis (vertical axis) via the air bearing 101 by the rotation mechanism 103. The slider table 102 is configured to be movable along a rail 105 extending in the Y-axis direction by a horizontal movement mechanism 104 provided on its lower surface side. The rail 105 is provided on a base 106. Note that the drive source of the horizontal movement mechanism 104 is not particularly limited, and for example, a linear motor is used.

[0025] Inside the chuck 100, a cooling mechanism 100a for cooling the polymerized wafer T adsorbed and held by the chuck 100 is provided. The configuration of the cooling mechanism 100a is not particularly limited as long as it can appropriately cool the polymerized wafer T (especially in the vicinity of the irradiated portion of the laser beam for interface), and for example, a Peltier element or the like can be used.

[0026] Above the chuck 100, a laser irradiation system 110 is provided. The laser irradiation system 110 has a laser head 111 and a lens 112. The lens 112 may be configured to be movable up and down by an elevating mechanism (not shown).

[0027] The laser head 111 has a laser oscillator (not shown) that oscillates laser light in pulses. That is, the laser light irradiated from the laser irradiation system 110 onto the polymerization wafer T held by the chuck 100 is so-called pulsed laser, and its power repeats between 0 (zero) and the maximum value. Also, in the present embodiment, the laser light is CO2 laser light, and the wavelength of the CO2 laser light is, for example, 8.9 μm to 11 μm. Note that the laser head 111 may have other devices of the laser oscillator, such as an amplifier.

[0028] The lens 112 is a cylindrical member and irradiates the polymerization wafer T held by the chuck 100 with laser light. The laser light emitted from the laser irradiation system 110 passes through the first wafer W and is irradiated onto the laser absorption film Fw and absorbed.

[0029] In the illustrated example, the chuck 100 is configured to be rotatable and movable horizontally relative to the laser head 111 by the rotation mechanism 103 and the horizontal movement mechanism 104. However, the laser head 111 may be configured to be rotatable and movable horizontally relative to the chuck 100. Also, both the chuck 100 and the laser head 111 may be configured to be rotatable and movable horizontally relative to each other.

[0030] The laser head 111 may further have a spatial light modulator (not shown). The spatial light modulator modulates and outputs the laser light. Specifically, the spatial light modulator can control the focal position and phase of the laser light, and can adjust the shape and number (branch number) of the irradiated laser light. At this time, the laser light branched and irradiated is configured such that the output, shape, etc. can be adjusted for each branch. As the spatial light modulator, for example, LCOS (Liquid Crystal Silicon) can be selected.

[0031] The internal modification device 60 irradiates the interior of the first wafer W with a laser beam (internal laser beam, such as a YAG laser), and forms a peripheral modification layer M1 that serves as a basis for separating the peripheral portion We, and a division modification layer M2 that serves as a basis for fragmenting the peripheral portion We. The configuration of the internal modification device 60 is not particularly limited. In one example, the internal modification device 60 includes a chuck that holds the polymerized wafer T on the upper surface, a rotation mechanism that relatively rotates the chuck and the polymerized wafer (first wafer W), a movement mechanism that relatively moves the chuck and the polymerized wafer (first wafer W) in the horizontal direction, and a laser irradiation unit (laser head) that irradiates the interior of the first wafer W held by the chuck with the internal laser beam.

[0032] The peripheral removal device 70 as a separation device performs removal of the peripheral portion We of the first wafer W, that is, edge trimming, based on the peripheral modification layer M1 formed in the internal modification device 60. The method of edge trimming can be arbitrarily selected. In one example, in the peripheral removal device 70, for example, a blade having a wedge shape may be inserted between the first wafer W and the second wafer S. Also, for example, air blow or water jet may be jetted toward the peripheral portion We to apply an impact to the peripheral portion We.

[0033] The cleaning device 80 performs a cleaning process on the first wafer W and the second wafer S after edge trimming by the peripheral removal device 70, and removes particles on these wafers. The cleaning method can be arbitrarily selected.

[0034] The above wafer processing system 1 is provided with a control device 90. The control device 90 is, for example, a computer and has a program storage unit (not shown). The program storage unit stores a program for controlling the processing of the polymerized wafer T in the wafer processing system 1. Further, the program storage unit also stores a program for controlling the operations of the drive systems of the various processing devices and transfer devices described above to realize the wafer processing described later in the wafer processing system 1. Note that the above program may be recorded on a computer-readable storage medium H and installed from the storage medium H to the control device 90. Further, the storage medium H may be temporary or non-temporary.

[0035] Next, the wafer processing performed using the wafer processing system 1 configured as described above will be described. In this embodiment, the first wafer W and the second wafer S are bonded, and a polymerized wafer T is formed in advance.

[0036] First, a cassette C containing a plurality of polymerized wafers T is placed on the cassette mounting table 10 of the loading / unloading station 2.

[0037] Next, the polymerized wafer T in the cassette C is taken out by the wafer transfer device 20 and transferred to the interface modification device 50 via the transition device 30 and the wafer transfer device 40. In the interface modification device 50, while rotating the polymerized wafer T (the first wafer W) and moving it in the horizontal direction, pulsed interface laser light L2 is irradiated onto the interface between the first wafer W and the second wafer S at the peripheral edge We (more specifically, the laser absorption film Fw formed on the interface). As a result, as shown in FIG. 4(a), peeling occurs at the interface between the first wafer W and the second wafer S.

[0038] In the interface modification device 50, due to the peeling occurring at the interface between the first wafer W and the second wafer S in this way, an unbonded region Ae with a reduced bonding strength between the first wafer W and the second wafer S is formed. As a result, an annular unbonded region Ae and, inside the radial direction of the unbonded region Ae, a bonded region Ac where the first wafer W and the second wafer S are bonded are formed at the interface between the first wafer W and the second wafer S, as shown in FIG. 5. In the edge trim described later, the peripheral portion We of the first wafer W to be removed is removed. However, due to the presence of the unbonded region Ae in this way, such removal of the peripheral portion We can be appropriately performed.

[0039] Note that the detailed formation method of the unbonded region Ae in the interface modification device 50 will be described later.

[0040] The polymerized wafer T in which the unbonded region Ae is formed is then transported to the internal modification device 60. In the internal modification device 60, as shown in FIG. 4(b), the internal laser beam L1 is irradiated inside the first wafer W to form the peripheral modification layer M1 and the division modification layer M2. The peripheral modification layer M1 serves as a reference point when removing the peripheral portion We in the edge trim described later. The division modification layer M2 serves as a reference point for fragmenting the small pieces of the peripheral portion We to be removed. In the drawings used in the following description, in order to avoid complexity in the illustration, the illustration of the division modification layer M2 may be omitted.

[0041] The polymerized wafer T in which the peripheral modification layer M1 and the division modification layer M2 are formed inside the first wafer W is then transported to the peripheral removal device 70 by the wafer transport device 40. In the peripheral removal device 70, as shown in FIG. 4(c), the peripheral portion We of the first wafer W, that is, the edge trim, is performed. At this time, the peripheral portion We is separated from the central portion (inside the radial direction of the peripheral portion We) of the first wafer W with the peripheral modification layer M1 as a reference point and is completely separated from the second wafer S with the unbonded region Ae as a reference point. Also at this time, the peripheral portion We to be removed is fragmented with the division modification layer M2 as a reference point.

[0042] In removing the peripheral portion We, for example, a blade B having a wedge shape (see FIG. 4(c)) may be inserted at the interface between the first wafer W and the second wafer S for forming the polymerized wafer T.

[0043] The polymerized wafer T from which the peripheral portion We of the first wafer W has been removed is then conveyed by the wafer transfer device 40 to the cleaning device 80. In the cleaning device 80, the first wafer W and / or the second wafer S after the peripheral portion We has been removed is cleaned.

[0044] In the cleaning device 80, as shown in FIG. 4(d), for example, the cleaning laser beam L3 may be irradiated onto the first wafer W and the second wafer S to modify and remove the irradiated portions of the laser beam, thereby removing (cleaning) residual particles and the like.

[0045] Thereafter, the polymerized wafer T that has undergone all the processes is conveyed by the wafer transfer device 20 to the cassette C on the cassette mounting table 10 via the wafer transfer device 40 and the transition device 30. Thus, a series of wafer processes in the wafer processing system 1 is completed.

[0046] In the above description, as shown in FIGS. 4(a) and 4(b), after the unbonded region Ae is formed by the interface modification device 50, the peripheral modification layer M1 and the division modification layer M2 are formed by the internal modification device 60. However, the order of the wafer processes in the wafer processing system 1 is not limited to this. That is, after the peripheral modification layer M1 and the division modification layer M2 are formed by the internal modification device 60, the unbonded region Ae may be formed by the interface modification device 50.

[0047] Next, a detailed method for forming the above-described unbonded region Ae will be described with reference to the drawings.

[0048] As described above, the inventors have found that in the interface modification apparatus 50, by controlling the temperature of the polymerization wafer T during irradiation with the interface laser beam L2, it is possible to more preferably form the unbonded region Ae. Therefore, in the wafer processing according to the present embodiment, in the interface modification apparatus 50, the temperature of the polymerization wafer T is controlled under various conditions to appropriately form the unbonded region Ae.

[0049] In the interface modification apparatus 50, first, as layer information of the polymerization wafer T that is the formation target of the unbonded region Ae, for example, the thickness and structure of the layer (in this embodiment, for example, the laser absorption film Fw) that forms the peeling surface of the first wafer W are acquired. The acquired layer information of the polymerization wafer T is output to the control device 90. The layer information of the polymerization wafer T may be acquired by the interface modification apparatus 50 or may be acquired in advance outside the interface modification apparatus 50. Further, the method for obtaining the layer information of the polymerization wafer T is not particularly limited, and it may be measured by, for example, a sensor or the like, or may be obtained by imaging the polymerization wafer T with a camera or the like.

[0050] When the layer information of the polymerization wafer T is acquired, next, the interface laser beam L2 is irradiated onto the laser absorption film Fw at a position corresponding to the peripheral edge We of the first wafer W to be removed in this embodiment inside the polymerization wafer T held by the chuck 100 based on the acquired layer information, and the unbonded region Ae is formed.

[0051] In the interface modification device 50, the interface laser light L2 is irradiated onto the laser absorption film Fw formed on the first wafer W from the laser irradiation system 110. The irradiated interface laser light L2 is absorbed by the laser absorption film Fw. At this time, the laser absorption film Fw accumulates energy by absorbing the interface laser light L2, causing the temperature to rise and expand. As a result, shear stress is generated at the interface between the first wafer W and the laser absorption film Fw due to the expansion of the laser absorption film Fw. This causes peeling at the interface where the bonding force between the first wafer W and the second wafer S is weak (in this embodiment, the interface between the laser absorption film Fw and the bonding film Fs). That is, at the irradiation position of the interface laser light L2, an unbonded region Ae with a reduced bonding force due to the peeling between the first wafer W and the second wafer S is formed.

[0052] Here, as shown in FIG. 6, the interface laser light L2 is irradiated onto the laser absorption film Fw in a pulsed manner at a substantially constant irradiation pitch Q (the irradiation interval of the physical interface laser light L2). At this time, the shear stress σ generated at the interface between the first wafer W and the laser absorption film Fw is considered to increase as the temperature difference ΔT between the temperature T1 in the directly irradiated region R1 where the interface laser light L2 shown in FIG. 6 is directly irradiated and the temperature T2 in the peripheral region R2 between one directly irradiated region R1 and another directly irradiated region R1 that are continuously formed becomes larger. In other words, in the interface modification device 50, by controlling the formation operation of the unbonded region Ae so that the temperature difference ΔT shown in FIG. 6 becomes larger, it is considered that the peripheral portion We of the first wafer W can be appropriately removed in the edge trim performed later by the peripheral removal device 70.

[0053] Therefore, in the interface modification device 50 according to the present embodiment, when forming the unbonded region Ae, at least one of the following controls is executed by the control device 90.

[0054] The first control is a method of controlling the repetition frequency (Repetition Frequency: hereinafter simply referred to as "frequency") of the interface laser light L2 irradiated onto the laser absorption film Fw.

[0055] As described above, the laser absorption film Fw that absorbs the interface laser beam L2 accumulates energy and its temperature rises. At this time, as shown in FIG. 6, the temperature of the laser absorption film Fw rises significantly in the immediate vicinity region R1 immediately below the irradiation of the interface laser beam L2, and the temperature of the peripheral region R2 also rises.

[0056] In such a case, when the frequency of the interface laser beam L2 is high, the interface laser beam L2 for forming another immediate vicinity region R1 is irradiated before the peripheral region R2 whose temperature has risen due to the formation of one immediate vicinity region R1 is cooled. That is, when successively forming one adjacent immediate vicinity region R1 and another immediate vicinity region R1, the temperature T2 of the peripheral region R2 therebetween may become stuck at a high level, and there is a risk that the temperature difference ΔT cannot be ensured.

[0057] Therefore, in the present embodiment, the frequency of the interface laser beam L2 is changed based on the layer information of the polymerization wafer T acquired prior to the irradiation of the interface laser beam L2. More specifically, the frequency of the interface laser beam L2 irradiated to a portion where peeling is considered difficult based on the layer information (for example, a portion where the thickness of the laser absorption film Fw is large or a portion having a film type of the laser absorption film Fw that is difficult to peel) is made smaller than that of other portions where peeling can be normally performed.

[0058] By thus reducing the frequency of the interface laser beam L2, the temporal pulse interval of the interface laser beam L2 becomes larger (for example, doubling the temporal pulse interval by halving the frequency of the interface laser beam L2). And when the temporal pulse interval of the interface laser beam L2 becomes longer, the natural cooling amount of the peripheral region R2 in the pulse interval increases, so that the temperature T2 of the peripheral region R2 at the time of the next irradiation of the interface laser beam L2 becomes lower, and the temperature difference ΔT shown in FIG. 6 can be increased.

[0059] In other words, according to the technology according to the present disclosure, based on the layer information at the irradiation position of the interface laser beam L2, the temperature difference ΔT is independently controlled between a portion where peeling is considered difficult and other portions where peeling can be normally performed.

[0060] Here, FIG. 7 is a table showing the peeling state of the first wafer W and the second wafer S when the unbonded region Ae is formed using the interface laser beam L2 with different frequencies. In this embodiment, the peeling states of the first wafer W and the second wafer S when the frequency of the interface laser beam L2 is 100 kHz and when the frequency is 50 kHz were respectively confirmed. Note that in this embodiment, conditions other than the frequency of the interface laser beam L2 (for example, the thickness and structure as layer information of the laser absorption film Fw, the rotation speed of the polymerized wafer T, etc.) were the same.

[0061] As shown in FIG. 7, even when the interface laser beam L2 is irradiated with the same irradiation pitch Q (see FIG. 6) and energy amount on the laser absorption film Fw having the same layer information, it was found that the range of conditions under which the first wafer W and the second wafer S can be peeled without problems expands by decreasing the frequency. This is presumably because even when the interface laser beam L2 is irradiated with the same irradiation pitch Q and energy amount, the cooling time of the peripheral region R2 increases due to the decrease in frequency, and as a result, the temperature difference ΔT shown in FIG. 6 becomes larger.

[0062] Note that from the viewpoint of appropriately peeling the first wafer W and the second wafer S by forming the unbonded region Ae, it is desirable that the irradiation pitch Q, which is the physical irradiation interval of the interface laser beam L2, be controlled at a predetermined constant value. In other words, it is desirable that the irradiation pitch Q be controlled to be constant in the portion where peeling is difficult obtained based on the above-described layer information and in the other portion where peeling can be normally performed. In view of this point, in order to control the irradiation pitch Q of the interface laser beam L2 to be substantially constant, it is desirable that the rotational speed of the polymerization wafer T (corresponding to the irradiation pitch Q in the circumferential direction) and the moving speed in the horizontal direction (corresponding to the irradiation pitch Q in the radial direction) be appropriately changed according to the frequency of the interface laser beam L2. More specifically, when the frequency of the interface laser beam L2 is decreased, it is desirable to simultaneously decrease the rotational speed and the moving speed of the polymerization wafer T so as to control the irradiation pitch Q of the interface laser beam L2 to be constant.

[0063] However, when the frequency of the interface laser beam L2 is decreased in this way (to a low frequency) or appropriately changed, the first wafer W and the second wafer S can be peeled off to appropriately form the unbonded region Ae, but the time required to form the unbonded region Ae over the entire surface of the peripheral portion We increases. In other words, when performing frequency control of the interface laser beam L2 in the interface modification apparatus 50, there is a trade-off relationship between appropriately forming the unbonded region Ae and improving the throughput related to the formation of the unbonded region Ae. In view of this point, considering the throughput in the interface modification apparatus 50, it is desirable to irradiate the interface laser beam L2 at the minimum controllable frequency. In the present embodiment, as described above, the unbonded region Ae is appropriately formed by decreasing the frequency of the interface laser beam L2 only in the portion where it is recognized that the peeling of the first wafer W and the second wafer S is difficult, and the frequency of the interface laser beam L2 is restored (set to a high frequency) in the other portions where peeling can be normally performed, thereby suppressing a decrease in throughput.

[0064] Also, the time required for the peripheral region R2 whose temperature has risen due to the formation of the region R1 directly below to be cooled to the temperature before the irradiation of the interface laser beam L2 is presumed to be constant according to the energy amount of the interface laser beam L2 regardless of the frequency of the interface laser beam L2. In view of such a point, it is desirable that the frequency of the laser light L2 for the interface is controlled such that the time interval between the pulses of the laser light L2 for the interface is substantially the same as or longer than the time required for the peripheral region R2 to be cooled to the temperature before the irradiation of the laser light L2 for the interface.

[0065] In addition, when the laser head 111 has the above-described spatial light modulator (for example, LCOS), the laser light L2 for the interface may be simultaneously irradiated to a plurality of different points of the laser absorption film Fw in a plan view. At this time, in order to appropriately enjoy the peeling effect of the first wafer W and the second wafer S due to the above-described temperature difference ΔT, a plurality of points (a plurality of condensing point positions) in the plane of the laser absorption film Fw where the laser light L2 for the interface is simultaneously irradiated are desirably arranged so as not to be adjacent at least in the circumferential direction and the radial direction in a plan view.

[0066] Specifically, for example, as shown in FIG. 8A(a), a plurality of, in the illustrated example, two laser lights L2 for the interface are irradiated at an irradiation interval twice the irradiation pitch Q (see FIG. 6) with respect to the circumferential direction of the superposed wafer T (with an interval corresponding to one peripheral region R2 corresponding to one directly below region R1 and a size of one), and a plurality of directly below regions R1 may be formed simultaneously. Subsequently, as shown in FIG. 8A(b), the condensing point positions of each of the plurality of laser lights L2 for the interface are shifted by the irradiation pitch Q in the circumferential direction and continuously irradiated, and by simultaneously forming a plurality of other directly below regions R1, peeling of the first wafer W and the second wafer S can be caused simultaneously at a plurality of points of the laser absorption film Fw in a plan view, and the throughput related to the formation of the unbonded region Ae can be improved. At this time, by controlling the frequency of the laser light L2 for the interface based on the layer information of the superposed wafer T as described above, the temperature of the peripheral region R2 between the plurality of directly below regions R1 during the formation of the plurality of other directly below regions R1 can be decreased. As a result, the temperature difference ΔT shown in FIG. 6 can be increased, and the unbonded region Ae can be appropriately formed.

[0067] Note that the arrangement of the plurality of interface laser beams L2 that are simultaneously irradiated is not limited to the arrangement in which they are arranged at intervals in the circumferential direction shown in FIG. 8A. As shown in FIG. 8B(a), a plurality of, in the illustrated example, two interface laser beams L2 may be arranged at intervals (twice the irradiation pitch Q) with respect to the radial direction of the polymerized wafer T. Further, for example, as shown in FIG. 8B(b), a plurality of, in the illustrated example, two interface laser beams L2 may be provided with an irradiation interval of the irradiation pitch Q with respect to both the radial direction and the circumferential direction of the polymerized wafer T, that is, arranged such that a plurality of condensing points are obliquely arranged in a plan view.

[0068] Thus, in the present embodiment, the positions of the plurality of condensing points are arranged so as not to be adjacent to each other at least in the circumferential direction and the radial direction in a plan view of the laser absorption film Fw, and the plurality of interface laser beams L2 are simultaneously irradiated. As a result, the temperature difference ΔT between the temperature T2 of the peripheral region R2 between the plurality of one directly below regions R1 and the plurality of other directly below regions R1 that are continuously formed can be increased. As a result, the unbonded regions Ae can be appropriately formed simultaneously at a plurality of points in a plan view, and the throughput related to the formation of the unbonded regions Ae can be improved.

[0069] Note that the number of the interface laser beams L2 that are simultaneously irradiated is not limited to two, and three or more interface laser beams L2 may be simultaneously irradiated onto the laser absorption film Fw. At this time, the condensing point positions of the three or more interface laser beams L2 may be arranged at intervals in the circumferential direction, the radial direction, or the oblique direction of the polymerized wafer T in a plan view, or may be arranged by combining the arrangements in the circumferential direction, the radial direction, or the oblique direction.

[0070] The second control is a method of cooling the polymerized wafer T by a cooling mechanism 100a disposed inside the chuck 100.

[0071] As described above, it is considered that the shear stress σ generated at the interface between the first wafer W and the laser absorption film Fw increases as the temperature difference ΔT between the temperature T1 of the directly below region R1 and the temperature T2 of the peripheral region R2 increases. In view of this point, when irradiating the interface laser beam L2, the polymerization wafer T may be cooled by the cooling mechanism 100a to lower the temperature T2 of the peripheral region R2, thereby increasing the temperature difference ΔT shown in FIG. 6.

[0072] In the example shown in FIG. 3, the cooling mechanism 100a is disposed inside the chuck 100, but the configuration and arrangement of the cooling mechanism 100a are not limited thereto.

[0073] Specifically, instead of or in addition to disposing the cooling mechanism 100a inside the chuck 100, an air nozzle 100b as a cooling mechanism for supplying cooling air Air to the surface of the polymerization wafer T (the back surface Wb of the first wafer W) as shown in FIG. 9A may be disposed. The air nozzle 100b is connected to a cooling air supply source 113. The temperature of the cooling air Air is not particularly limited as long as it can cool the polymerization wafer T and does not interfere with the irradiation of the interface laser beam L2, and may be, for example, room temperature, a low temperature below room temperature, or an extremely low temperature. When irradiating the interface laser beam L2 onto the polymerization wafer T, the air nozzle 100b supplies the cooling air Air from above to the central portion of the polymerization wafer T, and cools the entire surface of the polymerization wafer T by centrifugal force. By cooling the polymerization wafer T in this way, the temperature T2 of the peripheral region R2 can be lowered, and the temperature difference ΔT shown in FIG. 6 can be increased.

[0074] When locally supplying the cooling air Air to the peripheral region R2 in this way, the irradiation position of the interface laser beam L2 may be determined based on the supply position of the cooling air Air. In other words, the interface laser beam L2 may be irradiated using the cooling air Air as a guide.

[0075] From the perspective of appropriately peeling the first wafer W and the second wafer S to form the unbonded region Ae, as described above, it is considered that it is sufficient to increase the temperature difference ΔT between the immediate region R1 directly under the irradiation of at least the interface laser beam L2 and its peripheral region R2. In other words, it is not necessarily required to cool the entire surface of the bonded wafer T as in the cooling mechanism 100a and the air nozzle 100b described above. It is considered that the unbonded region Ae can be appropriately formed as long as at least the peripheral region R2 in the vicinity directly under the irradiation of the interface laser beam L2 can be cooled. From such a perspective, instead of or in addition to the cooling mechanism 100a and the air nozzle 100b described above, a mechanism for locally cooling the peripheral region R2 may be provided.

[0076] Specifically, for example, as shown in FIG. 9B, an air nozzle 100c as a cooling mechanism for supplying cooling air Air toward the peripheral region R2 when irradiating the interface laser beam L2 on the bonded wafer T may be arranged. The air nozzle 100c is connected to a cooling air supply source 114. Thereby, the temperature T2 of the peripheral region R2 can be lowered, and the temperature difference ΔT shown in FIG. 6 can be increased.

[0077] Note that the air nozzle 100c for locally cooling the peripheral region R2 may be integrally formed with the laser irradiation system 110 that irradiates the interface laser beam L2 as shown in FIG. 9C.

[0078] In the interface modification apparatus 50 according to the present embodiment, at least one of the above controls is executed by the control device 90, and an unbonded region Ae is formed on the entire surface of the bonded wafer T at a position corresponding to the peripheral edge We of the first wafer W to be removed.

[0079] According to the present embodiment, when forming the unbonded region Ae, control is executed so that the temperature difference ΔT between the temperature T1 of the immediate region R1 directly under the irradiation of the interface laser beam L2 and the temperature T2 of its peripheral region R2 becomes large. Specifically, by controlling at least one of the frequency of the interface laser beam L2 or the temperature of the bonded wafer T, the temperature T2 of the peripheral region R2 at the time of irradiation of the interface laser beam L2 is lowered, thereby increasing the temperature difference ΔT. As a result, the laser absorption film Fw expands due to the absorption of the interface laser beam L2, thereby increasing the shear stress σ generated between the immediate region R1 and the peripheral region R2. Consequently, the first wafer W and the second wafer S can be appropriately peeled off.

[0080] Further, according to the present embodiment, such temperature control is performed only on portions where peeling is considered difficult under normal high-frequency peeling conditions (irradiation conditions of the interface laser beam L2), particularly in the in-plane direction of the peripheral portion We. As a result, the first wafer W and the second wafer S can be appropriately peeled off in portions where peeling is difficult under the normal peeling conditions to form the unbonded region Ae, and in other portions, irradiation with the interface laser beam L2 is performed under the normal peeling conditions, thereby suppressing a decrease in throughput required for forming the unbonded region Ae and improving the formation efficiency of the unbonded region Ae in the interface modification apparatus 50.

[0081] In the above embodiment, portions where peeling is difficult are detected based on the previously acquired layer information, and control for increasing the temperature difference ΔT (temperature control of the polymerized wafer T and irradiation condition control of the interface laser beam L2) is performed on these difficult-to-peel portions. However, in the interface modification apparatus 50, in addition to this, similar control may be performed to appropriately peel the first wafer W and the second wafer S on the radially inner side (the formation side of the peripheral modification layer M1) of the peripheral portion We where the processing quality in edge trimming is important. In other words, control of the frequency of the interface laser beam L2 (temperature difference ΔT shown in FIG. 6) may be performed based on the radial position of the focus point of the interface laser beam L2 in the plane of the polymerized wafer T.

[0082] In such a case, by increasing the temperature difference ΔT inside the radial direction of the peripheral portion We where the formation accuracy of the unbonded region Ae affects the processing quality of the edge trim, the first wafer W and the second wafer S can be appropriately peeled off, and the processing accuracy and processing quality of the edge trim can be improved. At the same time, by setting the frequency of the interface laser beam L2 irradiated to the outer side in the radial direction of the peripheral portion We (the outer edge side of the first wafer W) with little influence on the processing quality to a high frequency (normal peeling conditions), the throughput related to the formation of the unbonded region Ae can be improved.

[0083] In the above embodiment, as shown in FIG. 4, the interface laser beam L2 is irradiated to the laser absorption film Fw formed at the interface between the first wafer W and the second wafer S, and the unbonded region Ae (peeling surface) is formed at the interface between the laser absorption film Fw and the bonding film Fs. However, the formation position of the unbonded region Ae is not limited to this as long as the peripheral portion We of the first wafer W can be appropriately removed. More specifically, for example, the unbonded region Ae is formed at an interface with a weak bonding force between the first wafer W and the second wafer S. However, the formation interface of such an unbonded region Ae can be the interface between the laser absorption film Fw and the first wafer W or the device layer Dw, or the interface between the first wafer W and the device layer Ds. Also, for example, instead of the laser absorption film Fw, the interface laser beam L2 may be irradiated to the bonding film Fs to form the unbonded region Ae.

[0084] In the above embodiment, the case of removing the peripheral portion We of the first wafer W in the polymerized wafer T in which the first wafer W and the second wafer S are bonded is described as an example. However, the technology according to the present disclosure can also be applied to the case of removing the entire first wafer W from the second wafer S, that is, the so-called laser lift-off process of the polymerized wafer T. Specifically, as shown in FIG. 10, even when an unbonded region Ae is formed over the entire bonding interface between the first wafer W and the second wafer S in the bonded wafer T, by increasing the temperature difference ΔT between the directly underlying region R1 and the peripheral region R2 during the formation of the unbonded region Ae, the first wafer W can be appropriately peeled off from the second wafer S. At this time, it is desirable that the frequency of the interface laser light L2 irradiated on the interface between the first wafer W and the second wafer S be determined based on the layer information acquired in advance.

[0085] In the above embodiments, the shape (shape of the condensing point) of the interface laser light L2 irradiated on the interface between the first wafer W and the second wafer S was not particularly limited. However, for example, when the condensing point shape of the interface laser light L2 is a circular shape as also shown in FIG. 6, as shown in FIG. 11A, in a plan view, a region (the white portion in FIG. 11A: hereinafter referred to as the "non-heated region R3") where the thermal influence of the interface laser light L2 does not reach the interface (laser absorption film Fw) between the first wafer W and the second wafer S is generated, and there is a possibility that the unbonded region Ae cannot be appropriately formed in such a non-heated region R3. Therefore, when the laser head 111 has the above-described spatial light modulator (for example, LCOS), it is desirable to control the condensing point shape of the interface laser light L2 so as to reduce the area of the non-heated region R3.

[0086] Specifically, for example, as shown in FIG. 11B, it is desirable to control the condensing point shape of the interface laser light L2 to be a substantially trapezoidal shape having a short side on the inner side in the radial direction of the bonded wafer T and a long side on the outer side in the radial direction in a plan view. Also at this time, particularly when the unbonded region Ae is formed over the entire bonding interface between the first wafer W and the second wafer S, it is desirable to reduce the length of the short side and / or the long side (width of the trapezoidal shape) of the substantially trapezoidal shape as the irradiation position of the interface laser light L2 moves toward the inner side in the radial direction of the bonded wafer T. By making the irradiation shape of the interface laser beam L2 substantially trapezoidal in this way, the non-heated region R3 formed at the interface (laser absorption film Fw) between the first wafer W and the second wafer S can be eliminated or the area can be reduced. As a result, the entire peripheral edge We, which is the formation target of the unbonded region Ae, can be appropriately peeled off.

[0087] Note that the irradiation shape of the interface laser beam L2 is not limited to the shape shown in FIG. 11B. For example, the short side and / or long side of the trapezoidal shape may have a curvature adapted to the concentric shape of the bonded wafers T (laser absorption film Fw). In this case, the area of the non-heated region R3 can be further reduced. Also, for example, as long as the area of the non-heated region R3 described above can be at least reduced, the irradiation shape of the interface laser beam L2 is not limited to a substantially trapezoidal shape. For example, as shown in FIG. 11C, polygons with four or more sides (hexagon in the illustrated example) may be tiled, or as shown in FIG. 11D, triangles may be tiled alternately.

[0088] In the above embodiments, the case where the laser absorption film Fw is an oxide film formed on the device layer Dw as shown in FIG. 1 has been described as an example. However, the laser absorption film for absorbing the laser beam may be formed between the first wafer W and the device layer Dw. More specifically, as shown in FIG. 12, a laser absorption film P, a device layer Dw, and a bonding film F are laminated in this order on the surface Wa of the first wafer W, and a device layer Ds and a bonding film Fs are laminated in this order on the surface Sa of the second wafer S.

[0089] The laser absorption film P is, for example, an oxide film (SiO2 film, TEOS film) and absorbs laser light in the same manner as the above-described laser absorption film Fw. The device layers Dw and Ds include a plurality of devices. As the bonding films F and Fs, for example, oxide films (THOX film, SiO2 film, TEOS film), SiC film, SiCN film, or an adhesive is used, and the first wafer W and the second wafer S are bonded via these bonding films F and Fs.

[0090] Hereinafter, a method for removing the first wafer W from the second wafer S when a laser absorption film P for absorbing laser light is formed between the first wafer W and the device layer Dw will be described. In the following description, when removing all of the first wafer W from the second wafer S as shown in FIG. 10, that is, when transferring the device layer Dw formed on the first wafer W to the second wafer S, an example will be used for the description.

[0091] When transferring the device layer Dw to the second wafer S, first, as shown in FIG. 13, in the interface modification device 50, the laser absorption film P, more specifically, the interface laser light L2 (CO2 laser light) is pulsed onto the interface between the laser absorption film P and the first wafer W (step St1 in FIG. 14). The interface laser light L2 irradiated from the back surface Wb side of the first wafer W passes through the silicon (first wafer W) and is absorbed by the laser absorption film P as shown in FIG. 13 (step St2 in FIG. 14).

[0092] The interface laser light L2 absorbed by the laser absorption film P is converted into heat according to its energy distribution (step St3 in FIG. 14). In other words, the temperature of the laser absorption film P increases due to the absorption of the interface laser light L2. The heat (Ht in the figure) generated in the laser absorption film P due to the absorption of the interface laser light L2 mostly diffuses toward the first wafer W side as shown in FIG. 15 (step St4 in FIG. 14). In other words, due to the heat diffusion from the laser absorption film P, the temperature of the interface between the laser absorption film P and the first wafer W (silicon) increases.

[0093] When the heat generated in the laser absorption film P diffuses toward the first wafer W side, due to the influence of this heat, that is, the increase in the interface temperature between the laser absorption film P and the first wafer W, as shown in FIG. 16, the first wafer W in the irradiated portion of the interface laser light L2 locally expands (plastically deforms into a downward convex shape with respect to the laser absorption film P side) according to its temperature distribution (step St5 in FIG. 14). Hereinafter, the region affected by the heat generated by the irradiation of the interface laser beam L2 may be referred to as the "irradiation region R" of the interface laser beam L2. In other words, the first wafer W locally expands in the irradiation region R of the interface laser beam L2.

[0094] Then, in the interface modification apparatus 50, the interface laser beam L2 is irradiated onto the entire surface of the laser absorption film P in a plan view. In other words, as shown in FIG. 17, the interface laser beam L2 is irradiated a plurality of times at intervals onto the entire surface of the laser absorption film P. At this time, the first wafer W locally expands every time the laser beam L1 is irradiated, that is, a plurality of irradiation regions R are formed at intervals in different portions in a plan view.

[0095] Here, when the first wafer W expands, as the first wafer W expands, the laser absorption film P is pressed from above (the first wafer W side), and thereby, as shown in FIG. 17, a compressive stress σ1 is generated in the laser absorption film P at the irradiation position of the interface laser beam L2. The generated compressive stress σ1 acts in the direction of separating the first wafer W and the laser absorption film P (the downward direction in the figure, the laser absorption film P side) as shown in FIG. 17 to generate a peeling stress σ2. In other words, in the irradiation region R of the interface laser beam L2, silicon (the first wafer W) expands in the region R1 immediately below the irradiation of the interface laser beam L2 (see FIG. 8 etc.) to generate a compressive stress σ1, and a peeling stress σ2, which is a stress in the peeling direction caused by the compressive stress σ1, is generated in the peripheral region R2, particularly at the end Re of the irradiation region R (see FIG. 16). This peeling stress σ2 is a tensile stress generated in the peripheral region R2 (see FIG. 8 etc.) of the irradiation region R.

[0096] The generated compressive stress σ1 and peeling stress σ2 are accumulated inside the laser absorption film P. At this time, at the end Re of the irradiation region R, the peeling stresses σ2 generated in the plurality of irradiation regions R act multiplicatively (repeatedly).

[0097] When the total accumulated amount (product amount) of the peeling stress σ2 at the end Re of the irradiation region R exceeds the adhesion Σ per unit area between the first wafer W and the laser absorption film P at the end Re (n×σ2 > Σ, where n is a natural number and the number of irradiations of the laser beam L1), peeling occurs at the interface between the first wafer W and the laser absorption film P at the end Re of the irradiation region R as shown in FIG. 18. As a result, the bonding strength between the laser absorption film P and the first wafer W decreases (step St6 in FIG. 14). Note that the stress σ (compressive stress σ1 and peeling stress σ2) accumulated inside the laser absorption film P is released by the peeling of the first wafer W and the laser absorption film P.

[0098] Then, in the interface modification device 50, as shown in FIG. 19, by causing peeling over the entire surface of the interface between the first wafer W and the laser absorption film P in plan view, in other words, by connecting the peeling that occurred at the end Re of the irradiation region R over the entire surface of the interface between the first wafer W and the laser absorption film P, the bonding strength is decreased over the entire surface of the first wafer W and the laser absorption film P, whereby the first wafer W and the laser absorption film P can be appropriately separated in a subsequent separation process (step St7 in FIG. 14).

[0099] Note that the separation of the first wafer W from the laser absorption film P may be performed in a separation device (not shown) arranged in the wafer processing system 1, or may be performed inside the interface modification device 50. The method of separating the first wafer W from the laser absorption film P can be arbitrarily determined.

[0100] At this time, in the polymerized wafer T after the irradiation of the interface laser beam L2 in the interface modification apparatus 50, peeling occurs between the entire surface of the first wafer W and the laser absorption film P. In other words, after peeling occurs at the end Re of the irradiation region R, it is ideal that the first wafer W and the laser absorption film P are peeled also at the central portion of the irradiation region R including the region directly under the irradiation, due to the peeling stress σ2. However, as shown in FIG. 18, in the central portion of the irradiation region R (the region directly under the irradiation of the laser beam L1), even after peeling occurs at the end Re of the irradiation region R, the state where the first wafer W and the laser absorption film P remain connected (non-peeled state) may be maintained. For this reason, in the wafer processing system 1 according to the technology of the present disclosure, in order to surely separate the first wafer W from the polymerized wafer T (laser absorption film P) in the polymerized wafer T after the irradiation of the interface laser beam L2, it is preferable to arrange a separation device (not shown) and provide a step of separating the first wafer W from the polymerized wafer T in the separation device.

[0101] Here, when separating the first wafer W from the polymerized wafer T in this manner at a separation position such as a separation device (not shown), if the polymerized wafer T is transported to the separation position in the above-described ideal state, that is, in a state where peeling occurs between the entire surface of the first wafer W and the laser absorption film P, the first wafer W may fall from the second wafer S due to inertial force or the like accompanying this transportation. Further, if peeling occurs between the entire surface of the first wafer W and the laser absorption film P in this manner, even when it is not necessary to transport the polymerized wafer T after the irradiation of the interface laser beam L2 to the separation position, there is a risk that the first wafer W may fly off the second wafer S due to centrifugal force or the like accompanying the rotation of the chuck 100 during the irradiation of the interface laser beam L2 on the laser absorption film P in the interface modification apparatus 50.

[0102] In view of this point, in order to prevent the first wafer W from scattering and falling during the irradiation of the interface laser beam L2 on the laser absorption film P and during the conveyance of the polymerization wafer T, in the interface modification apparatus 50, it is preferable to control the irradiation conditions (such as irradiation position and output) of the interface laser beam L2 so as to maintain at least a part of the interface between the first wafer W and the laser absorption film P in a connected state (a state where it is not peeled off). Thereby, during the irradiation of the interface laser beam L2 or during conveyance to the separation position, etc., it is possible to suppress the complete separation of the first wafer W from the laser absorption film P and the scattering and falling of the second wafer S from the laser absorption film P.

[0103] The transfer of the device layer Dw formed on the first wafer W to the second wafer S is performed as described above. That is, in the interface modification apparatus 50, the first wafer W is expanded by the heat generated by the irradiation of the interface laser beam L2, and a compressive stress σ1 is generated in the laser absorption film P, thereby generating a peeling stress σ2 at the interface between the first wafer W and the laser absorption film P. Thereby, peeling occurs at the interface between the laser absorption film P and the first wafer W, reducing the bonding strength. Then, after reducing the bonding strength over the entire surface of the laser absorption film P and the first wafer W, the first wafer W is removed from the laser absorption film P, for example, by raising it in a separation device (not shown) or in the interface modification apparatus 50.

[0104] Further, in the above embodiment, when the laser absorption film P for absorbing the laser beam is formed between the first wafer W and the device layer Dw, the case where all of the first wafer W is removed from the second wafer S has been described as an example. However, a part of the first wafer W may be removed from the second wafer S. Specifically, for example, as shown in FIG. 4, a peripheral portion We may be removed from the second wafer S as a part of the first wafer W, that is, a so-called edge trim process may be performed.

[0105] The embodiments disclosed this time should be considered illustrative in all respects and not restrictive. The above embodiments may be omitted, substituted, or changed in various forms without departing from the scope and gist of the appended claims.

Explanation of Reference Numerals

[0106] 1 Wafer processing system 50 Interface modification device 70 Peripheral removal device 90 Control device Ae Unbonded region Fw Laser absorption film L2 Laser light for interface R1 Region directly below R2 Peripheral region S Second wafer T Bonded wafer T1 Temperature (of the region directly below) T2 Temperature (of the peripheral region) W First wafer ΔT Temperature difference

Claims

1. A processing method for processing a polymerized substrate formed by laminating a first substrate on which a laser absorption film is formed and a second substrate, comprising: irradiating the laser absorption film with laser light; locally expanding the first substrate by the heat generated by irradiating the laser light, and causing peeling at the interface between the first substrate and the laser absorption film due to the stress generated by the expansion. Processing method.

2. Due to the stress generated by the expansion of the first substrate, causing the peeling at the interface between the first substrate and the laser absorption film in a peripheral region formed between one focusing point and another focusing point where the laser light is irradiated after the one focusing point, according to the processing method of Claim 1.

3. accumulating the stress by irradiating the laser absorption film with the laser light irradiated a plurality of times at intervals, and causing the peeling at the interface between the first substrate and the laser absorption film due to the accumulated stress, according to the processing method of Claim 2.

4. causing the peeling in different regions at the interface between the first substrate and the laser absorption film; forming a separation surface serving as a base point for separating the first substrate and the laser absorption film by connecting the peeling occurring in the different regions, according to the processing method of Claim 3.

5. including separating and removing at least a part of the first substrate from the polymerized substrate with the separation surface as a base point, according to the processing method of Claim 4.

6. The processing method according to any one of Claims 2 to 5, wherein the peeling between the first substrate and the laser absorption film is generated by a tensile stress occurring in the peripheral region.

7. including forming a peripheral modification layer serving as a base point for separating the peripheral portion along the boundary between the peripheral portion and the central portion of the first substrate to be removed; when separating the first substrate, separating the peripheral portion of the first substrate from the second substrate, according to the processing method of any one of Claims 1 to 6.

8. A processing system for processing a polymerized substrate formed by laminating a first substrate on which a laser absorption film is formed and a second substrate, comprising: an interface modification device that irradiates the laser absorption film with pulsed laser light to form an unbonded region where the bonding strength between the first substrate and the second substrate is reduced. A separation device that separates the first substrate from the second substrate, and a control device, wherein the control device, in the interface modification device, irradiates the laser absorption film with laser light, locally expands the first substrate by the heat generated by the irradiation of the laser light, and causes peeling to occur at the interface between the first substrate and the laser absorption film due to the stress generated by the expansion. A processing system that executes control including this.

9. The control device, in the interface modification device, due to the stress generated by the expansion of the first substrate, executes control including causing the peeling to occur at the interface between the first substrate and the laser absorption film in a peripheral region formed between one focusing point and another focusing point where the laser light is irradiated after the one focusing point. The processing system according to claim 8.

10. The control device, in the interface modification device, accumulates the stress by irradiating the laser absorption film with the laser light irradiated a plurality of times at intervals, and executes control including causing the peeling to occur at the interface between the first substrate and the laser absorption film due to the accumulated stress. The processing system according to claim 9.

11. The control device, in the interface modification device, causes the peeling to occur in different regions at the interface between the first substrate and the laser absorption film, and executes control including forming a separation surface that becomes a base point for separating the first substrate and the laser absorption film by connecting the peeling that occurred in the different regions. The processing system according to claim 10.

12. The control device, executes control including separating and removing at least a part of the first substrate from the polymer substrate with the separation surface as a base point. The processing system according to claim 11.

13. The control device, in the interface modification device, causes the peeling between the first substrate and the laser absorption film to be generated by tensile stress occurring in the peripheral region. The processing system according to any one of claims 9 to 12.

14. The control device, in the interface modification device, executes control including forming a peripheral modification layer that becomes a base point for separating the peripheral edge of the first substrate to be removed along the boundary between the peripheral edge and the central portion of the first substrate. The processing system according to any one of claims 8 to 13, wherein, when separating the first substrate, control including separating the peripheral portion of the first substrate from the second substrate is executed.

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