JP7285151B2 - Support peeling method and support peeling system - Google Patents

Description

The present disclosure relates to a substrate stripping method and a substrate stripping system.

Patent Literature 1 discloses a member peeling method for peeling first and second members bonded to each other via an adhesive layer. This member peeling method includes the steps of disposing a photothermal conversion layer on a first main surface of a first member; irradiating the photothermal conversion layer with laser light; applying force to the first member and the second member to separate the first member from the second member; have

JP 2015-122370 A

The technique according to the present disclosure efficiently separates the support from the polymer in which the substrate and the support are bonded via an adhesive layer.

One aspect of the present disclosure is a support peeling method for peeling the support from a polymer in which the substrate and the support are bonded via an adhesive layer, wherein the substrate includes a plurality of substrates having circuits formed thereon. It has a circuit-forming region and a non-circuit-forming region in which the circuit is not formed between the adjacent circuit-forming regions, the support transmits light, and the adhesive layer absorbs the light. a step of irradiating at least part of the non-circuit-forming region that has changed properties with the light through the support; and applying a force to the polymer irradiated with the light to remove the support from the polymer. and exfoliating, wherein the circuit formation region is rectangular and the non-circuit formation region is lattice-shaped, and in the step of irradiating light, from one end to the other end of the non-circuit formation region The light is applied to the non-circuit-forming region extending toward.

According to the present disclosure, the support can be efficiently peeled off from the polymer in which the substrate and the support are bonded via the adhesive layer.

1 is a plan view showing an outline of the configuration of a peeling system according to this embodiment; FIG. FIG. 4 is a side view showing the outline of the configuration of the superposed wafer; It is a top view which shows the outline of a structure of a device wafer. It is a side view which shows the outline of a structure of a laser irradiation apparatus. It is a top view which shows the outline of a structure of a laser irradiation apparatus. It is an explanatory view showing an outline of composition of a laser head. FIG. 4 is a flow chart showing main steps of the peeling process; FIG. 10 is an explanatory diagram showing how to remove the adhesive protruding laterally from the superposed wafer; FIG. 10 is an explanatory diagram showing a state in which an adhesive protruding laterally from the superposed wafer is removed; It is explanatory drawing which shows a mode that an adhesive agent is denatured. It is explanatory drawing which shows a mode that the adhesive agent was denatured. It is explanatory drawing which shows a mode that the adhesive agent was denatured. FIG. 4 is an explanatory view showing how the adhesive scribe line and outer peripheral portion are altered; It is explanatory drawing which shows a mode that a device wafer and a support wafer are peeled off. FIG. 4 is an explanatory diagram showing how a blade is inserted into the bonding interface between a device wafer and a support wafer; FIG. 10 is an explanatory diagram showing a degeneration pattern of an adhesive according to another embodiment; It is a side view which shows the outline of a structure of the laser irradiation apparatus concerning other embodiment. It is a top view which shows the outline of a structure of the laser irradiation apparatus concerning other embodiment. It is a side view which shows the outline of a structure of the laser irradiation apparatus concerning other embodiment. It is explanatory drawing which shows a mode that the adhesive agent is denatured in other embodiment. It is explanatory drawing which shows a mode that the adhesive agent was denatured in other embodiment. It is explanatory drawing which shows a mode that the adhesive agent was denatured in other embodiment. It is explanatory drawing which shows a mode that a device wafer and a support wafer are peeled off in other embodiment. It is explanatory drawing which shows a mode that a device wafer and a support wafer are peeled off in other embodiment. FIG. 10 is a plan view showing an outline of the configuration of a peeling system according to another embodiment;

In recent years, there has been a demand for thinner semiconductor devices, and in the manufacturing process of such semiconductor devices, for example, in the TSV process and the Fanout process, a semiconductor wafer (hereinafter referred to as a wafer) having a device layer such as a plurality of circuits formed on its surface. is being thinned. If such a thinned wafer is transported as it is or subjected to subsequent processing such as photolithography processing, the wafer may be warped or cracked. Therefore, in order to reinforce the wafer, the wafer and the supporting substrate are joined together with an adhesive, for example. After subsequent processing is performed in a state in which the wafer and the support substrate are bonded, the support substrate is separated from the wafer.

Conventionally, various methods have been used to separate the wafer and the support substrate. As the main peeling methods, for example, there are a method of peeling by applying force to the wafer and the support substrate, and a method of irradiating the adhesive with a laser beam to peel the wafer and the support substrate. In the following description, the former separation method may be referred to as mechanical separation, and the latter method may be referred to as laser separation. In laser peeling, a peeling method using infrared light as laser light may be called IR laser peeling, and a peeling method using ultraviolet light may be called UV laser peeling.

In the mechanical peeling, for example, a blade is inserted into the bonding interface between the wafer and the support substrate to separate the support substrate from the wafer and separate it. Here, since it is necessary to perform, for example, a wafer thinning process while the wafer and the support substrate are bonded together before separation, a bonding strength that can withstand these processes is required. In other words, it is necessary to apply a somewhat large force (hereinafter referred to as peeling force) at the time of peeling, and in such a case, the load on the wafer is high, and there is a possibility that the wafer will crack. In addition, when a blade is used, it is difficult to select and adjust the blade, and moreover, it takes time and effort to maintain the blade due to wear. In addition, there are cases where three layers of adhesive are required for bonding the wafer and the support substrate, and it takes time to clean the adhesive to remove it after peeling.

In IR laser delamination, for example, infrared light is transmitted through the support substrate and irradiated to the adhesive, thereby changing the properties of the adhesive and detaching the wafer from the support substrate. Since the wavelength of this infrared light is long, the infrared light may pass through the adhesive and reach the device layer. As a result, the device layer is damaged.

In the UV laser delamination, for example, ultraviolet light is transmitted through the support substrate and irradiated to the adhesive, thereby changing the properties of the adhesive and detaching the wafer from the support substrate. In this case, a substrate that transmits ultraviolet rays, such as a glass substrate, is used as the support substrate. Since the glass substrate has a different coefficient of thermal expansion (CTE) from a wafer made of silicon, there is a difference in thermal deformation between the wafer and the glass substrate during heat treatment, for example.

As described above, mechanical delamination, IR laser delamination, and UV laser delamination each have their drawbacks. Therefore, as a result of intensive studies, the inventors of the present invention have come up with the idea of appropriately combining mechanical delamination and laser delamination to compensate for these drawbacks and to perform stable delamination processing efficiently.

In addition, in the peeling method described in the above-mentioned Patent Document 1, the photothermal conversion layer provided between the first member and the second member is irradiated with laser light, and the first member is separated from the second member. to separate the first member from the second member. However, in this peeling method, it is necessary to provide a photothermal conversion layer separately from the adhesive layer, which is troublesome and inefficient. Therefore, conventional stripping methods have room for improvement.

The technique according to the present disclosure efficiently separates the support from the polymer in which the substrate and the support are bonded via an adhesive layer. Hereinafter, a peeling system as a support peeling system and a peeling method as a support peeling method according to this embodiment will be described with reference to the drawings. In the present specification and drawings, elements having substantially the same functional configuration are denoted by the same reference numerals, thereby omitting redundant description.

<Configuration of peeling system>
First, the configuration of the peeling system according to this embodiment will be described. FIG. 1 is a plan view showing an outline of the configuration of the peeling system 1. FIG. To clarify the positional relationship, the X-axis direction, the Y-axis direction, and the Z-axis direction, which are orthogonal to each other, are defined below, and the Z-axis positive direction is defined as the vertically upward direction.

In the separation system 1, the support wafer S is separated from the superposed wafer T in which the device wafer W and the support wafer S are bonded via the adhesive G as shown in FIG. Note that the device wafer W corresponds to the substrate in the present disclosure, the support wafer S corresponds to the support in the present disclosure, the adhesive G corresponds to the adhesive layer in the present disclosure, and the polymerization wafer T corresponds to the polymer in the present disclosure. Equivalent to. Note that the adhesive G is formed in one layer.

Hereinafter, in the device wafer W, the surface bonded to the support wafer S via the adhesive G is referred to as a front surface Wa, and the surface opposite to the front surface Wa is referred to as a back surface Wb. Similarly, in the support wafer S, the surface bonded to the device wafer W via the adhesive G is called a front surface Sa, and the surface opposite to the front surface Sa is called a back surface Sb.

The device wafer W is, for example, a semiconductor wafer such as a silicon substrate, and a device layer D including a plurality of circuits and the like is formed on the surface Wa. The device wafer W is thinned by, for example, polishing the back surface Wb.

Further, as shown in FIG. 3, the device wafer W is diced and divided into a plurality of dies Wd by scribe lines Ws (also called streets). In the present embodiment, the die Wd is rectangular in plan view, and the scribe lines Ws are formed in a grid pattern. A circuit of the device layer D is formed on the surface of the die Wd, and the die Wd constitutes a circuit forming region in the present disclosure. A circuit is not formed on the scribe line Ws, and the scribe line Ws constitutes a non-circuit forming region in the present disclosure. Circuits are also not formed on the outer peripheral portion We of the device wafer W radially outside the die Wd and the scribe line Ws.

The support wafer S is a wafer that supports the device wafer W. FIG. A material that transmits infrared light is used for the support wafer S, and a silicon wafer, for example, is used.

The adhesive G adheres to the device wafer W and the support wafer S, and changes in quality by absorbing infrared light. Here, the term "alteration" refers to a state in which the adhesive G can be destroyed by receiving a slight external force, or a phenomenon in which the adhesive force between the adhesive G and a layer in contact with the adhesive G is reduced. That is, when the adhesive G absorbs the infrared light, the adhesive G becomes brittle and loses the bonding strength (adhesiveness) before being irradiated with the infrared light. More specifically, when the adhesive G absorbs infrared light, it is heated by the energy of the absorbed infrared light, melted, and carbonized. In this way, the adhesive G loses its adhesive function at the portion irradiated with the infrared light. Further, when the adhesive G protruding laterally from the superposed wafer T absorbs infrared light, the adhesive G is heated by the energy of the absorbed infrared light, and the adhesive G sublimates, thereby removing the protruding adhesive G. can do.

Also, as shown in FIG. 2, the superposed wafer T is fixed to the dicing frame F with the dicing tape P therebetween. Specifically, the superimposed wafer T is placed in the opening Fa of the dicing frame F, and the dicing tape P is attached to the rear surface Wb of the device wafer W and the rear surface of the dicing frame F so as to close the opening Fa from the rear surface. As a result, the superposed wafer T is fixed (held) on the dicing frame F. As shown in FIG.

As shown in FIG. 1, the peeling system 1 has a configuration in which a loading/unloading station 10, a transfer station 20, and a processing station 30 are connected together. For example, the loading/unloading station 10 loads/unloads cassettes Cw, Cs, and Ct that can accommodate a plurality of device wafers W, a plurality of support wafers S, and a plurality of superposed wafers T, respectively. The transfer station 20 transfers the device wafer W, the support wafer S, and the superposed wafer T between the loading/unloading station 10 and the processing station 30 . The processing station 30 includes various processing apparatuses for performing predetermined processing on the device wafer W, the support wafer S, and the superposed wafer T. As shown in FIG.

The loading/unloading station 10 is provided with a cassette mounting table 11 . In the illustrated example, a plurality of, for example, four cassettes Cw, Cs, and Ct can be placed in a row on the cassette placing table 11 in the X-axis direction. In this embodiment, the cassette Ct on the negative side of the X-axis is used as a loader cassette containing unprocessed stacked wafers T, and the cassettes Cw and Cs in the center of the X-axis are device wafers after processing (separation). It is used with an unloader cassette containing W and a support wafer S. Further, the cassette Ct on the X-axis positive direction side is used as an unloader cassette that collects and accommodates the overlapped wafers T that have failed during processing. The number of cassettes Cw, Cs, and Ct to be placed on the cassette placing table 11 is not limited to the number in this embodiment, and can be arbitrarily determined.

The transfer station 20 is provided adjacent to the loading/unloading station 10 . The transfer station 20 is provided with a wafer transfer device 22 which is movable on a transfer path 21 extending in the X-axis direction. The wafer transfer device 22 has two transfer arms 23 and 24, for example. The first transfer arm 23 is an arm for transferring the dicing frame, and transfers the superposed wafer T or the device wafer W fixed to the dicing frame F. As shown in FIG. The second transfer arm 24 is an arm for transferring wafers, and transfers the separated support wafer S. As shown in FIG. Each transport arm 23, 24 is configured to be movable in the horizontal direction, the vertical direction, around the horizontal axis, and around the vertical axis. Note that the configuration of the transport arms 23 and 24 is not limited to that of the present embodiment, and can take any configuration.

The processing station 30 is provided adjacent to the transfer station 20 . In the processing station 30, an alignment device 31, a laser irradiation device 32 as a light irradiation device, a peeling device 33, a first cleaning device 34, and a second cleaning device 35 are arranged on the positive Y-axis side of the transfer station 20. They are arranged side by side from the axial positive direction toward the negative direction. In the processing station 30 , a reversing device 36 is arranged on the X-axis positive direction side of the transfer station 20 . The number and arrangement of these devices 31 to 36 are not limited to this embodiment, and can be determined arbitrarily.

In the alignment device 31, for example, an IR camera (infrared camera) is used to detect the pattern of the device wafer W, that is, the pattern of the die Wd and the scribe line Ws, and adjust the position of the superposed wafer T. FIG. Since the alignment device 31 detects patterns in this way, it also functions as a detection device in the present disclosure. A known device is used for the alignment device 31 .

The laser irradiation device 32 irradiates the adhesive G through the support wafer S with infrared light, which is a laser beam. The configuration of the laser irradiation device 32 will be described later.

The peeling device 33 applies a force to the overlapped wafer T to separate the supporting wafer S from the overlapped wafer T. FIG. Specifically, after a blade is inserted into one end of the bonding interface between the device wafer W and the support wafer S, the support wafer S is separated from the device wafer W and separated from the one end toward the other end. . A known device is used for the peeling device 33 .

In the first cleaning device 34, the adhesive G is removed from the surface Wa of the device wafer W which is fixed to the dicing frame F and separated, and the surface Wa is spin-cleaned. A known device is used for the first cleaning device 34 .

In the second cleaning device 35, the adhesive G is removed from the surface Sa of the support wafer S after peeling, and the surface Sa is spin-cleaned. A known device is used for the second cleaning device 35 .

The reversing device 36 reverses the front and rear surfaces of the support wafer S after separation. A known device is used as the reversing device 36 .

A controller 40 is provided in the peeling system 1 described above. The control device 40 is, for example, a computer equipped with a CPU, memory, etc., and has a program storage unit (not shown). The program storage unit stores a program for controlling the peeling process in the peeling system 1 . The program storage unit also stores a program for controlling the operation of drive systems such as various processing devices and transport devices to realize the stripping process in the stripping system 1 . The program may be recorded in a computer-readable storage medium H and installed in the control device 40 from the storage medium H.

<Configuration of laser irradiation device>
Next, the laser irradiation device 32 mentioned above will be described. FIG. 4 is a side view showing a schematic configuration of the laser irradiation device 32. As shown in FIG. FIG. 5 is a plan view showing an outline of the configuration of the laser irradiation device 32. As shown in FIG.

The laser irradiation device 32 has a chuck 100 that holds the superposed wafer T on its upper surface. The chuck 100 holds the superimposed wafer T fixed to the dicing frame F by suction. A chuck 100 is supported by a slider table 102 via an air bearing 101 . A rotating 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 around the θ axis (vertical axis) via an air bearing 101 by a rotating mechanism 103 . The slider table 102 is configured to be movable along rails 105 provided on a base 106 and extending in the Y-axis direction by means of a moving mechanism 104 provided on the underside of the slider table 102 . Although the driving source of the moving mechanism 104 is not particularly limited, for example, a linear motor is used.

A laser head 110 as an infrared light irradiation unit is provided above the chuck 100 . The laser head 110 has a lens 111 . The lens 111 is a cylindrical member provided on the lower surface of the laser head 110 and irradiates the superposed wafer T held by the chuck 100 with laser light. In this embodiment, the laser light is infrared light, and the infrared light emitted from the laser head 110 is transmitted through the support wafer S and applied to the adhesive G. As shown in FIG.

A galvanometer, for example, is used for the laser head 110 . As shown in FIG. 6, a plurality of galvanomirrors 112 are arranged inside the laser head 110 . Also, an f-θ lens is used as the lens 111 . With such a configuration, the infrared light Lir input to the laser head 110 is reflected by the galvanomirror 112 , propagates to the lens 111 , and irradiates the adhesive G through the support wafer S. By adjusting the angle of the galvanomirror 112, the adhesive G can be scanned with the infrared light Lir.

Note that the laser head 110 is configured to be vertically movable by a lifting mechanism (not shown).

<Operation of the peeling system>
Next, the peeling process performed using the peeling system 1 configured as described above will be described. FIG. 7 is a flow chart showing main steps of the peeling process.

First, a cassette Ct containing a plurality of superposed wafers T is mounted on the cassette mounting table 11 of the loading/unloading station 10 . At this time, the superposed wafer T is fixed to the dicing frame F. As shown in FIG.

Next, the superposed wafer T in the cassette Ct is taken out by the first transfer arm 23 of the wafer transfer device 22 and transferred to the alignment device 31 . In the alignment apparatus 31, first, the IR camera is used to detect the pattern of the device wafer W, that is, the pattern of the die Wd and the scribe line Ws (step A1 in FIG. 7). Subsequently, position adjustment (alignment) of the overlapped wafer T is performed based on the pattern detection result (step A2 in FIG. 7).

Next, the superposed wafer T is transferred to the laser irradiation device 32 by the first transfer arm 23 of the wafer transfer device 22 . The superposed wafer T carried into the laser irradiation device 32 is held by the chuck 100 and further arranged at the processing position by the moving mechanism 104 . At this time, eccentricity control and circumferential position adjustment of the overlapped wafer T are performed based on the detection result of the pattern of the device wafer W in step A1 described above.

Subsequently, as shown in FIG. 8, while rotating the superimposed wafer T by the rotation mechanism 103, the laser head 110 irradiates the outer edge of the superimposed wafer T with the infrared light Lir. Here, if the adhesive G protrudes laterally from the superimposed wafer T as indicated by the dotted line in FIG. 9, the blade 140 may not be inserted at an appropriate position in the peeling device 33, which will be described later. Therefore, in the present embodiment, the infrared light Lir is applied to the outer edge of the superposed wafer T to remove the adhesive G protruding laterally from the superposed wafer T (step A3 in FIG. 7). Specifically, it is preferable that the end portion of the adhesive G be positioned at the end portion of the bevel portion (curved portion) of the support wafer S as shown in FIG.

Subsequently, as shown in FIG. 10, the adhesive G is irradiated with the infrared light Lir from the laser head 110 through the support wafer S, and the adhesive G is scanned with the infrared light Lir to scan the adhesive. The surface of G is altered (step A4 in FIG. 7). Specifically, as shown in FIGS. 11 and 12, the adhesives Gs and Ge at positions corresponding to the scribe lines Ws and the outer peripheral portion We of the device wafer W are irradiated with infrared light Lir to change their properties. Hereinafter, the adhesive Gs at the position corresponding to the scribe line Ws will be referred to as the scribe line Gs, and the adhesive Ge at the position corresponding to the outer peripheral portion We will be referred to as the outer peripheral portion Ge. FIG. 13 is an explanatory diagram showing how the scribe line Gs and the outer peripheral portion Ge of the adhesive G are altered.

First, as shown in FIG. 13A, while the rotating mechanism 103 rotates the superposed wafer T, the outer peripheral portion Ge of the adhesive G is irradiated with infrared light Lir from the laser head 110 . Then, the outer peripheral portion Ge is altered. At this time, the irradiation position of the infrared light Lir may be moved in the radial direction. That is, the infrared light Lir may be irradiated in a plurality of rings to form a plurality of ring-shaped altered portions in the outer peripheral portion Ge. Alternatively, while rotating the superposed wafer T, the irradiation position of the infrared light Lir may be moved in the radial direction to form the deteriorated portion in the outer peripheral portion Ge in a spiral shape.

Next, the scribe line Gs of the adhesive G is irradiated with infrared light Lir to change its quality. In this embodiment, as shown in FIGS. 13(b) to 13(e), the adhesive G is divided into four areas, and the respective areas G1 to G4 are altered. That is, first, as shown in FIG. 13B, in the first area G1 of the adhesive G, the infrared light Lir is scanned along the scribe lines Gs to alter the scribe lines Gs. After that, as shown in FIG. 13(c), the superposed wafer T is rotated by 90 degrees, and the infrared light Lir is scanned along the scribe lines Gs in the second area G2 to alter the scribe lines Gs. By repeating this, the scribe lines Gs in the third area G3 are altered as shown in FIG. 13(d), and the scribe lines Gs in the fourth area G4 are altered as shown in FIG. 13(e). . Thus, the scribe line Gs on the entire surface of the adhesive G is degraded.

In this embodiment, the adhesive G is denatured for each of the four areas G1 to G4, but the number of divisions is not limited to this. Further, the scribe line Gs on the entire surface of the adhesive G may be altered by one irradiation of the infrared light Lir without dividing the adhesive G. FIG.

However, since the angle of the galvanomirror 112 is determined within a certain range due to the configuration of the device, the laser head 110 needs to be arranged upward in order to cover the adhesive G with one infrared irradiation. In this case, the height of the peeling device 33 is increased and the size is increased. In addition, since the size of the lens 111, which is an f-θ lens, is roughly the size obtained by dividing the diameter of the adhesive G by the number of divisions, the number of divisions of the adhesive G when the infrared light Lir is irradiated is small. , the lens 111 becomes larger by that amount. In this case, the lens 111 becomes expensive, and the cost of the peeling device 33 increases. From the above, it is preferable to divide the adhesive G into a plurality of areas and irradiate the infrared light Lir for each area.

Further, the shape of the infrared light Lir irradiated to the scribe line Gs may be circular or rectangular. Further, for example, when the diameter of the infrared light Lir is small relative to the width of the scribe line Gs, one scribe line Gs may be irradiated with the infrared light Lir multiple times. The shape and irradiation method of the infrared light Lir can be arbitrarily set.

Further, in step A1 described above, the patterns of the die Wd and the scribe lines Ws of the device wafer W are detected, and in step A4, based on this detection result, the position to be irradiated with the infrared light Lir may be controlled. . In such a case, since the irradiation position can be controlled for each device wafer W, the scribe line Gs and the outer peripheral portion Ge of the adhesive G can be appropriately altered. However, the irradiation position of the infrared light Lir may be controlled based on predetermined design values, and such a method is also within the scope of the present disclosure.

Moreover, in the present embodiment, the scribe line Gs is altered after the outer peripheral portion Ge of the adhesive G is altered, but this order may be reversed. That is, after the scribe line Gs is altered, the outer peripheral portion Ge may be altered.

As described above, in step A4, the bonding strength between the device wafer W and the support wafer S can be reduced by altering the scribe line Gs and the outer peripheral portion Ge of the adhesive G, and the peeling force in step A5 described later can be reduced. can be lowered. Further, the infrared light Lir is irradiated only to the portion where the circuit is not formed, and is not irradiated to the portion where the circuit is formed. Therefore, the device layer D can be prevented from being damaged.

Next, the superposed wafer T is transferred to the peeling device 33 by the first transfer arm 23 of the wafer transfer device 22 . The peeling device 33 applies a force to the overlapped wafer T to separate the overlapped wafer T into the device wafer W and the support wafer S (step A5 in FIG. 7). FIG. 14 is an explanatory view showing how the device wafer W and the support wafer S are separated.

First, as shown in FIG. 14A, the entire surface of the device wafer W is sucked and held by the first holding portion 120 via the dicing tape P, and the support wafer S is held by the second holding portion 130 by suction. The second holding part 130 has a deformable thin plate-like elastic member 131 and a plurality of suction parts 132 for holding the support wafer S by suction. Note that the arrangement and number of the plurality of suction units 132 can be arbitrarily set. Also, instead of the plurality of suction portions 132, a deformable suction portion that suctions the support wafer S over its entire surface may be used.

Next, the blade 140 is inserted into the bonding interface between the device wafer W and the support wafer S as shown in FIG. 14(a). More specifically, the blade 140 is inserted into the interface between the support wafer S and the adhesive G as shown in FIG. 15(a). When the blade 140 is advanced further, a peeling start portion M is formed between the support wafer S and the adhesive G on the side surface on the one end S1 side, which triggers the peeling. Detachment of the support wafer S starts from this detachment start portion M. As shown in FIG. Note that the number of blades 140 may be plural.

Here, as described above, in step A1, the adhesive G protruding laterally from the superposed wafer T is removed. If the adhesive G protrudes laterally from the superimposed wafer T as shown in FIG. 15(b), the blade 140 will not be inserted at an appropriate position, and the peel start portion M will not be formed. Therefore, by performing step A1 as in this embodiment, the blade 140 can be stably inserted.

Next, as shown in FIG. 14B, the suction portion 132 on the one end S1 side is raised. Then, the support wafer S is sequentially peeled from the one end portion S1 toward the other end portion S2 with the peeling start portion M as a base point. Then, as shown in FIG. 14C, the suction portion 132 on the other end portion S2 side is also raised, and the support wafer S is separated from the device wafer W over its entire surface. At this time, since the bonding strength between the device wafer W and the support wafer S is reduced by deteriorating the scribe lines Gs and the outer peripheral portion Ge of the adhesive G in step A4, the device wafer W can be separated from the support wafer with a small peeling force. S can be peeled off.

Next, the delaminated device wafer W is transferred to the first cleaning apparatus 34 by the first transfer arm 23 of the wafer transfer apparatus 22 . In the first cleaning device 34, the adhesive G remaining on the device wafer W is removed and the surface Wa is spin-cleaned (step A6 in FIG. 7). In this step A6, the scribe line Gs and the outer peripheral portion Ge of the adhesive G are degraded, which facilitates cleaning. Therefore, cleaning time can be shortened compared to the case where the conventional adhesive G is not degraded. Furthermore, it is also possible to reduce the amount of cleaning liquid used in spin cleaning.

After that, the device wafer W that has undergone all the processes is transferred to the cassette Cw on the cassette mounting table 11 by the first transfer arm 23 of the wafer transfer device 22 .

As described above, in parallel with the step A6 being performed on the delaminated device wafer W, the delaminated support wafer S is also subjected to desired processing.

That is, the support wafer S after peeling is transferred to the reversing device 36 by the second transfer arm 24 of the wafer transfer device 22 . The reversing device 36 reverses the front and back surfaces of the support wafer S (step A7 in FIG. 7).

Next, the support wafer S is transferred to the second cleaning device 35 by the second transfer arm 24 of the wafer transfer device 22 . In the second cleaning device 35, the adhesive G remaining on the support wafer S is removed and the surface Sa is spin-cleaned (step A8 in FIG. 7).

After that, the support wafer S that has undergone all the processes is transferred to the cassette Cs on the cassette mounting table 11 by the second transfer arm 24 of the wafer transfer device 22 . Thus, a series of stripping processes in the stripping system 1 is completed.

According to the above embodiment, the support wafer S can be properly and efficiently separated from the superposed wafer T by combining IR laser separation and mechanical separation.

That is, it is possible to improve the above-described drawbacks when mechanical peeling is performed alone. According to this embodiment, the peeling force in step A5 can be reduced, and the load applied to the device wafer W can be reduced. In addition, since the peeling force is small, the selection and adjustment of the blade 140 are easy, and wear of the blade 140 can be suppressed to reduce maintenance frequency. Furthermore, in this embodiment, the adhesive G is a single layer, and the removal and cleaning of the adhesive G after peeling can be performed in a short time.

In addition, the above-mentioned drawbacks in the case of performing IR laser peeling alone can be improved. According to this embodiment, the infrared light Lir is used in step A4, but the infrared light Lir is irradiated only to the portion where the circuit is not formed, and is not irradiated to the portion where the circuit is formed. Therefore, the device layer D can be prevented from being damaged.

Furthermore, no UV laser peeling is performed, and there is no need to use a glass substrate for the support wafer S, and a silicon wafer is used. Then, for example, even if a heat treatment is performed, there is no difference in thermal deformation between the device wafer W and the support wafer S, and an appropriate bonding state can be maintained. Moreover, a silicon wafer is cheaper than a glass substrate, and the cost can be reduced.

<Other Embodiments of Alteration Pattern>
In the above embodiment, in step A4, the scribe line Gs and the outer peripheral portion Ge of the adhesive G are denatured by being irradiated with the infrared light Lir, but the denaturation pattern of the adhesive G is not limited to this. FIG. 16 is an explanatory diagram showing a degeneration pattern of the adhesive G according to another embodiment.

As shown in FIG. 16A, the outer peripheral portion Ge of the adhesive G may not be irradiated with the infrared light Lir, and only the scribe line Gs may be irradiated with the infrared light Lir to be altered. Further, as shown in FIG. 16B, in the scribe line Gs of the adhesive G, the infrared light Lir may be irradiated only to the outer peripheral portion without irradiating the central portion with the infrared light Lir to alter the scribe line Gs.

As shown in FIG. 16(c), only one end portion S1 of the scribe line Gs of the adhesive G may be irradiated with the infrared light Lir to alter the quality thereof. This one end S1 is the position where the blade 140 is inserted in step A5. By reducing the peeling force of the one end portion S1, it becomes easier to insert the blade 140, and it becomes easier to form the peeling start portion M.

As shown in FIG. 16(d), only the scribe line Gs of the adhesive G along the peeling direction J from the one end S1 to the other end S2 in step A5 may be irradiated with infrared rays to alter its quality. In this case, when the support wafer S is peeled off from the device wafer W in step A5, the peeling force in the peeling direction J becomes small, so that the peeling process can be easily performed.

As shown in FIG. 16(d), only the scribe line Gs of the adhesive G along the direction orthogonal to the peeling direction J from the one end S1 to the other end S2 in step A5 is irradiated with infrared rays to change its quality. may The peeling surface of the support wafer S in step A5 is perpendicular to the peeling direction J. As shown in FIG. In the example shown in FIG. 16E, the peeling force in the direction along the peeling surface is small, so the peeling process can be easily performed.

As described above, the deterioration pattern of the adhesive G shown in FIG. 16 is an example. If the area where the adhesive G is altered becomes large, the peeling force becomes small, which is advantageous for the peeling treatment. On the other hand, the larger the area of the adhesive G to be altered, the longer it takes to irradiate the infrared light Lir. Therefore, it is preferable to determine the deterioration pattern of the adhesive G by judging the processing time (tact) and the peeling force in combination.

<Another Embodiment of Laser Irradiation Method>
In the laser irradiation device 32 of the above embodiment, the chuck 100 is rotatable around the θ axis and is movable in one axis (Y axis) direction. good. FIG. 17 is a side view showing a schematic configuration of a laser irradiation device 200 according to another embodiment. FIG. 18 is a plan view showing a schematic configuration of a laser irradiation device 200 according to another embodiment.

The laser irradiation device 200 has a chuck 210 that holds the superposed wafer T on its upper surface. The chuck 210 holds the superimposed wafer T fixed to the dicing frame F by suction. A chuck 210 is supported by a slider table 212 via an air bearing 211 . A rotating mechanism 213 is provided on the lower surface side of the slider table 212 . The rotation mechanism 213 incorporates, for example, a motor as a drive source. The chuck 210 is configured to be rotatable around the θ axis (vertical axis) via an air bearing 211 by a rotating mechanism 213 . The slider table 212 is configured to be movable along a rail 215 provided on a moving stage 216 and extending in the Y-axis direction by a moving mechanism 214 provided on the underside thereof. Although the driving source of the moving mechanism 214 is not particularly limited, for example, a linear motor is used.

The moving stage 216 is configured to be movable along a rail 217 provided on a base 218 and extending in the X-axis by a moving mechanism (not shown) provided on the lower surface side. Although the driving source of the moving mechanism is not particularly limited, for example, a linear motor is used. With such a configuration, the chuck 100 is rotatable around the θ axis and movable along the X and Y axes.

A laser head 220 as an infrared light irradiation unit is provided above the chuck 210 . The laser head 110 has a lens 221 . The configurations of the laser head 220 and the lens 221 are the same as those of the laser head 110 and the lens 111 of the above embodiment.

Also when performing step A4 with such a laser irradiation device 200, the scribe line Gs and the outer peripheral portion Ge of the adhesive G are formed as shown in FIG. As shown in FIG. 13A, the method of altering the outer peripheral Ge is the same as that of the laser irradiation device 32 of the above embodiment, so the description is omitted.

Also, when the scribe line Gs is altered, the adhesive G is divided into four areas G1 to G4 as shown in FIGS. 13(b) to 13(e). However, in the laser irradiation device 32 of the above embodiment, the superposed wafer T is rotated by 90 degrees to move the areas G1 to G4 below the laser head 110. FIG. On the other hand, in the laser irradiation apparatus 200 of this embodiment, the superposed wafer T is moved along the X-axis and the Y-axis to move the areas G1 to G4 below the laser head 110. FIG.

Also in this embodiment, the same effects as in the above embodiment can be enjoyed. Moreover, since the overlapped wafer T (chuck 100) is not rotated, it is possible to omit the position adjustment of the overlapped wafer accompanying this rotation. However, the laser irradiation device 200 of this embodiment is larger than the laser irradiation device 32 .

In the above embodiment, IR laser separation and mechanical separation are combined to separate support wafer S from superposed wafer T, but UV laser separation may be further combined. FIG. 19 is a side view showing a schematic configuration of a laser irradiation device 250 according to another embodiment.

The laser irradiation device 250 has a configuration in which a laser head 260 and a lens 261 as an ultraviolet light irradiation section are added to the configuration of the laser irradiation device 32 . Therefore, constituent members other than the laser head 260 and the lens 261 are denoted by the same reference numerals as those of the laser irradiation device 32, and descriptions thereof are omitted.

A laser head 260 is provided above the chuck 100 . A lens 261 of the laser head 260 is a cylindrical member provided on the lower surface of the laser head 110 and irradiates the superposed wafer T held by the chuck 100 with laser light. In this embodiment, the laser light emitted from the laser head 260 is ultraviolet light. Further, in the present embodiment, a material that transmits ultraviolet light is used for the support wafer S, and for example, a glass substrate is used. The ultraviolet light emitted from the laser head 260 is transmitted through the support wafer S, and the adhesive G is irradiated with the ultraviolet light. Infrared light emitted from the laser head 110 also passes through the support wafer S.

When step A4 is performed with such a laser irradiation device 250, as shown in FIG. to irradiate the adhesive G with ultraviolet light Luv. It should be noted that either the infrared light Lir or the ultraviolet light Luv may be applied first. Also, the infrared light Lir and the ultraviolet light Luv may be irradiated at the same time.

As shown in FIGS. 21 and 22, the infrared light Lir irradiates the scribe line Gs and the outer peripheral portion Ge of the adhesive G, thereby altering the scribe line Gs and the outer peripheral portion Ge. The alteration of the scribe line Gs and the outer peripheral portion Ge by the infrared light Lir is the same as in the above embodiment.

On the other hand, the ultraviolet light Luv is applied to the adhesive Gd at the position corresponding to the die Wd of the device wafer W, and the adhesive Gd is degraded. The adhesive Gd at the position corresponding to the die Wd is hereinafter referred to as a die Gd. Even if the die Gd on which the circuit is formed is irradiated with the ultraviolet light Luv in this manner, the ultraviolet light Luv does not pass through the adhesive G and does not reach the circuit of the device layer D. FIG.

Also in this embodiment, it is possible to enjoy the same effects as in the above embodiment. Moreover, in addition to deterioration of the scribe line Gs and the outer peripheral portion Ge of the adhesive G by the infrared light Lir, the die Gd is also deteriorated by the ultraviolet light Luv. can be done. Since the ultraviolet light Luv does not reach the circuit, it is possible to prevent the device layer D from being damaged.

In this embodiment, the scribe line Gs of the adhesive G, the outer peripheral portion Ge, and the die Gd are irradiated with the ultraviolet light Luv without irradiating the infrared light Lir. The die Gd may be altered. However, the combined use of the infrared light Lir and the ultraviolet light Luv can shorten the processing time (tact).

<Another embodiment of the peeling method>
In the peeling apparatus 33 of the above embodiment, the support wafer S is sequentially peeled from the device wafer W from the one end S1 toward the other end S2 in step A5. It can be peeled off.

As shown in FIG. 23A, the entire surface of the device wafer W is sucked and held by the first holding portion 270 via the dicing tape P, and the entire surface of the support wafer S is sucked and held by the second holding portion 280 . Subsequently, the blade 290 is inserted into the bonding interface between the device wafer W and the support wafer S. As shown in FIG. Then, a peeling start portion M, which triggers peeling, is formed between the support wafer S and the adhesive G on the side surface on the one end portion S1 side. Detachment of the support wafer S starts from this detachment start portion M. As shown in FIG.

Next, as shown in FIG. 23(b), the second holding portion 280 is raised. Then, the entire support wafer S is separated from the device wafer W. As shown in FIG. Even in such a case, the scribe lines Gs and the outer peripheral portion Ge of the adhesive G are degraded in step A4, and the bonding strength between the device wafer W and the support wafer S is reduced. S can be peeled off.

Furthermore, in the above embodiment, when inserting the blade 290 as shown in FIG. 24(a), the second holding part 280 that sucks and holds the support wafer S may be rotated. In this case, the peeling start portion M can be formed over the entire circumference, and the peeling process can be performed more easily.

In the above embodiment, the blades 140 and 290 are used to form the separation start portion M when the device wafer W and the support wafer S are separated by the separation device 33. However, if the separation force is sufficiently small, Blades 140, 290 may be omitted.

<Another embodiment of the peeling system>
Although the separation system 1 of the above embodiment has the alignment device 31, the laser irradiation device 32, and the separation device 33 separately, they may be provided as one device as shown in FIG. A processing apparatus 300 integrating an alignment device 31, a laser irradiation device 32, and a peeling device 33 has an alignment section 301, a laser irradiation section 302, and a peeling section 303, for example. The processing apparatus 300 is provided with one chuck 310 that holds the superimposed wafer T, and rails 311 laid across the alignment section 301 , the laser irradiation section 302 , and the separation section 303 . The chuck 310 is configured to be movable between the alignment section 301 , the laser irradiation section 302 and the peeling section 303 along the rails 311 . Components of the alignment unit 301, the laser irradiation unit 302, and the separation unit 303 are the same as those of the alignment device 31, the laser irradiation device 32, and the separation device 33 of the above embodiment.

In such a case, first, the chuck 310 is arranged in the alignment section 301, the pattern of the device wafer W is detected in step A1, and the position of the overlapped wafer T is adjusted in step A2. Next, the chuck 310 is moved to the laser irradiation section 302 to remove the adhesive G in step A3 and degrade the adhesive G in step A4. Next, the chuck 310 is moved to the separating section 303 to separate the device wafer W and the support wafer S in step A5. Subsequent steps A6 to A8 are the same as in the above embodiment.

Also in this embodiment, the same effects as in the above embodiment can be enjoyed. Moreover, according to this embodiment, since steps A1 to A5 are performed by moving the chuck 310, the transfer by the wafer transfer device 22 can be omitted, and the throughput of the peeling process can be further improved.

<Other embodiments>
In the above embodiment, the die Wd formed on the device wafer W has a rectangular shape, but the shape of the die Wd is not limited to this, and for example, the die Wd may have a hexagonal shape. Moreover, although the dies Wd are formed in alignment with the X-axis and the Y-axis, the arrangement of the dies Wd is not limited to this, and may be arranged in a zigzag pattern, for example. In either case, the scribe line Ws is formed so as to surround the outer periphery of the die Wd.

In the above embodiments, the adhesive G is used as the adhesive layer for bonding the device wafer W and the support wafer S, but an adhesive tape may be used, for example.

It should be considered that the embodiments disclosed this time are illustrative in all respects and not restrictive. The embodiments described above may be omitted, substituted, or modified in various ways without departing from the scope and spirit of the appended claims.

Note that the following configuration also belongs to the technical scope of the present disclosure.
(1) A support peeling method for peeling the support from a polymer in which a substrate and a support are bonded via an adhesive layer, wherein the substrate includes a plurality of circuit forming regions on which circuits are formed. and a non-circuit-forming region in which the circuit is not formed between the adjacent circuit-forming regions, the support transmits light, the adhesive layer changes in quality by absorbing the light, and the a step of irradiating at least part of the non-circuit-forming region with the light through the support; and a step of applying a force to the polymer irradiated with the light to peel off the support from the polymer. A method for stripping a support, comprising:
(2) The support peeling method according to (1) above, wherein the circuit-forming region is rectangular and the non-circuit-forming region is grid-shaped.
(3) The method for removing a support according to (2) above, wherein in the step of irradiating with light, the light is applied to the outer peripheral portion of the non-circuit forming region.
(4) The method for removing a support according to (2) above, wherein in the step of irradiating with light, one end portion of the non-circuit forming region is irradiated with the light.
(5) The support release according to (2) above, wherein in the step of irradiating with light, the non-circuit-forming region extending from one end of the non-circuit-forming region toward the other end is irradiated with the light. Method.
(6) The method for peeling a support according to any one of (1) to (5) above, wherein the light is infrared light.
(7) The method for removing a support according to (6) above, wherein in the step of irradiating with light, at least part of the circuit forming region is irradiated with ultraviolet light.
(8) The method for peeling a support according to any one of (1) to (5) above, wherein the light is ultraviolet light.
(9) In the step of irradiating with light, before irradiating at least part of the non-circuit-forming region with the light, the adhesive layer protruding laterally from the polymer is irradiated with the light, The support peeling method according to any one of (1) to (8) above, wherein the adhesive layer is removed.
(10) The method for peeling off a support according to any one of (1) to (9), further comprising a step of detecting the non-circuit-forming region before the step of irradiating with light.
(11) The method for peeling a support according to any one of (1) to (10), wherein in the step of peeling the support, the support is sequentially peeled from one end toward the other end.
(12) The support peeling method according to any one of (1) to (10) above, wherein in the step of peeling the support, the entire surface of the support is separated from the substrate and peeled.
(13) The method for peeling a support according to (11) or (12) above, wherein in the step of peeling the support, a peel initiation portion that triggers peeling of the support is formed at one end of the prepolymer.
(14) A support peeling system for peeling the support from a polymer in which the substrate and the support are bonded via an adhesive layer, wherein the substrate includes a plurality of circuit forming regions on which circuits are formed. and a non-circuit-forming region in which the circuit is not formed between the adjacent circuit-forming regions, the support transmits light, the adhesive layer changes in quality by absorbing the light, and the a light irradiation device that irradiates the light onto at least part of the non-circuit-forming region through the support;
and a peeling device for applying a force to the polymer irradiated with the light to peel the support from the polymer.
(15) The substrate peeling system according to (14), wherein the circuit-forming region is rectangular and the non-circuit-forming region is grid-shaped.
(16) The support peeling system according to (15), wherein the light irradiation device irradiates the light to the outer peripheral portion of the non-circuit formation region.
(17) The support peeling system according to (15), wherein the light irradiation device irradiates one end of the non-circuit forming region with the light.
(18) The support peeling system according to (15), wherein the light irradiation device irradiates the non-circuit-forming region extending from one end of the non-circuit-forming region toward the other end with the light.
(19) The light irradiation device includes an infrared light irradiation unit that irradiates infrared light to at least part of the non-circuit formation region;
The support peeling system according to any one of the above (14) to (18), further comprising an ultraviolet light irradiating section that irradiates ultraviolet light onto at least part of the circuit forming region.
(20) The support peeling system according to any one of (14) to (19) above, comprising a detection device that detects the non-circuit-forming region.

Reference Signs List 1 peeling system 32 laser irradiation device 33 peeling device G adhesive S support wafer T polymerized wafer W device wafer Wd die Ws scribe line

Claims (12)

A support peeling method for peeling a support from a polymer in which a substrate and a support are bonded via an adhesive layer,
The substrate has a plurality of circuit forming regions in which circuits are formed and non-circuit forming regions in which the circuits are not formed between the adjacent circuit forming regions,
the support is permeable to light;
The adhesive layer is altered by absorbing the light,
a step of irradiating at least part of the non-circuit-forming region with the light through the support;
a step of applying a force to the polymer irradiated with the light to peel the support from the polymer ;
the circuit formation region is rectangular, the non-circuit formation region is grid-shaped,
In the step of irradiating with light, the non-circuit-forming region extending from one end of the non-circuit-forming region toward the other end is irradiated with the light. A support peeling method for peeling a support from a polymer in which a substrate and a support are bonded via an adhesive layer,
The substrate has a plurality of circuit forming regions in which circuits are formed and non-circuit forming regions in which the circuits are not formed between the adjacent circuit forming regions,
the support is permeable to light;
The adhesive layer is altered by absorbing the light,
a step of irradiating at least part of the non-circuit-forming region with the light through the support;
a step of applying a force to the polymer irradiated with the light to peel the support from the polymer ;
the light is infrared light;
In the step of irradiating with light, at least part of the circuit forming region is irradiated with ultraviolet light . A support peeling method for peeling a support from a polymer in which a substrate and a support are bonded via an adhesive layer,
The substrate has a plurality of circuit forming regions in which circuits are formed and non-circuit forming regions in which the circuits are not formed between the adjacent circuit forming regions,
the support is permeable to light;
The adhesive layer is altered by absorbing the light,
a step of irradiating at least part of the non-circuit-forming region with the light through the support;
a step of applying a force to the polymer irradiated with the light to peel the support from the polymer ;
In the step of irradiating with light, the adhesive layer protruding laterally from the polymer is irradiated with the light to remove the adhesive layer;
A support peeling method, wherein in the step of peeling the support from the polymer, a blade is inserted into the interface between the support and the adhesive layer . 4. The method for removing a support according to claim 1 , further comprising a step of detecting said non-circuit forming region before said step of irradiating said light. The support peeling method according to any one of claims 1 to 4 , wherein in the step of peeling the support, the support is sequentially peeled from one end toward the other end. 5. The method for removing a support according to claim 1 , wherein in the step of removing the support, the entire surface of the support is separated from the substrate. 7. The method for peeling a support according to claim 5 , wherein in the step of peeling the support, a peeling initiation portion that triggers the peeling of the support is formed at one end of the prepolymer. A support peeling system for peeling a support from a polymer in which a substrate and a support are bonded via an adhesive layer,
The substrate has a plurality of circuit forming regions in which circuits are formed and non-circuit forming regions in which the circuits are not formed between the adjacent circuit forming regions,
the support is permeable to light;
The adhesive layer is altered by absorbing the light,
a light irradiation device that irradiates the light onto at least part of the non-circuit-forming region through the support;
a peeling device for applying a force to the polymer irradiated with the light to peel the support from the polymer ;
the circuit formation region is rectangular, the non-circuit formation region is grid-shaped,
In the light irradiation device, a substrate peeling system that irradiates the non-circuit-forming region extending from one end of the non-circuit-forming region toward the other end with the light. A support peeling system for peeling a support from a polymer in which a substrate and a support are bonded via an adhesive layer,
The substrate has a plurality of circuit forming regions in which circuits are formed and non-circuit forming regions in which the circuits are not formed between the adjacent circuit forming regions,
the support is permeable to light;
The adhesive layer is altered by absorbing the light,
a light irradiation device that irradiates the light onto at least part of the non-circuit-forming region through the support;
a peeling device for applying a force to the polymer irradiated with the light to peel the support from the polymer ;
the light is infrared light;
The support peeling system , wherein the light irradiation device irradiates at least part of the circuit forming region with ultraviolet light . A support peeling system for peeling a support from a polymer in which a substrate and a support are bonded via an adhesive layer,
The substrate has a plurality of circuit forming regions in which circuits are formed and non-circuit forming regions in which the circuits are not formed between the adjacent circuit forming regions,
the support is permeable to light;
The adhesive layer is altered by absorbing the light,
a light irradiation device that irradiates the light onto at least part of the non-circuit-forming region through the support;
a peeling device for applying a force to the polymer irradiated with the light to peel the support from the polymer ;
In the light irradiation device, the adhesive layer protruding laterally from the polymer is irradiated with the light to remove the adhesive layer,
In the peeling device, in the step of peeling the support from the polymer, a support peeling system in which a blade is inserted into an interface between the support and the adhesive layer. The light irradiation device is
an infrared light irradiation unit that irradiates infrared light to at least part of the non-circuit formation region;
11. The support peeling system according to any one of claims 8 to 10 , further comprising an ultraviolet light irradiation section for irradiating ultraviolet light onto at least part of the circuit forming region. 12. The substrate peeling system according to any one of claims 8 to 11 , further comprising a detection device for detecting said non-circuit forming area.

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