TWI755505B - sheet expansion device - Google Patents

Abstract

[Problem] To provide a sheet expanding device capable of dividing a workpiece or a film-like adhesive without leaving an undivided region and suppressing the occurrence of breakage of the expanding sheet. [Solution] The sheet expansion device is provided with: annular frame fixing means (20) for fixing the annular frame (11); expansion means (30, 31) for pressing the expansion sheet (12) to make it Expansion; elastic wave detection sensors (50, 51, 52, 53), which detect the elastic waves generated when the workpiece (13) or the film-like adhesive is broken along the dividing starting point (16) due to the expansion of the expansion sheet; and means of control (40). The control means is based on the value of the output signal from the elastic wave detection sensor when the workpiece or the film-like adhesive is completely broken, and is stored in advance as a threshold value. When the output signal of the detector does not reach the threshold, it is considered that there is an unbroken area and an error signal is output.

Description

sheet expansion device

The present invention relates to a sheet expansion device for dividing workpieces such as wafers or film-like adhesives.

A technology in which a semiconductor wafer is irradiated with a penetrating laser beam along a predetermined dividing line, and a modified layer is formed as the starting point of the dividing by absorbing multiple photons, and the wafer is divided by using the modified layer as the starting point of the dividing. public. In addition, a technique for forming laser processing grooves, dicing grooves, etc. as a starting point of division other than the modified layer is also known. When dividing a substantially disk-shaped workpiece, such as a wafer having a starting point for division, along the planned division line, first, the workpiece is adhered to the expansion piece that is stretched on the annular frame. In addition, by expanding the expansion piece, an external force is applied to the workpiece, and a crack penetrating in the thickness direction is generated from the starting point of division, and the workpiece is divided (refer to Patent Document 1).

In addition, there has been disclosed a technique for dividing a workpiece having a thin film adhesive made of epoxy resin or the like with a thickness of several μm to 100 μm called DAF (Die Attach Film) on the backside. . When the workpiece and the DAF are both divided by the expansion of the expansion sheet, a wafer to which the DAF is attached will be formed. The wafer is finally heated and bonded to a predetermined object via DAF (refer to Patent Document 2).

In the sheet expansion device for dividing (expanding and breaking) a workpiece by the expansion of the expansion sheet as described above, it is connected between the annular frame holding the peripheral portion of the expansion sheet and the region of the expansion sheet to which the workpiece is adhered. The expansion piece is expanded by relative movement in the thickness direction of the workpiece. For example, a well-known sheet expansion device has a structure in which a ring-shaped frame is fixed and held, and the expansion sheet is pushed up by a push-up member.

If the relative push-up of the push-up member is insufficient, the expansion of the expansion piece will be insufficient. Then, since the external force cannot be properly applied to the workpiece, the workpiece cannot be sufficiently divided, and undivided regions are generated in some of the planned division lines. Here, the undivided region refers to a region in which there is no crack penetrating in the thickness direction among the regions along the line to be divided, and the workpiece is not properly divided. On the other hand, if the relative push-up of the push-up member is excessive, the expansion sheet may not be resistant to expansion and break.

The appropriate value of the relative lift amount of the lift member with respect to the annular frame varies depending on the size of each wafer formed by dividing the workpiece, the type of the expansion piece, and the like. Therefore, an experiment or the like is performed in advance to obtain a value of the push-up amount suitable for the size of the wafer or the type of the expansion sheet, and the relative push-up amount of the push-up member is set to an appropriate value before expanding the expansion sheet. [Prior Art Documents] [Patent Documents]

[Patent Document 1] Japanese Patent No. 3408805 [Patent Document 2] Japanese Patent Laid-Open No. 2009-272503

[Problem to be Solved by the Invention] However, even in the case of setting the relative lifting amount of the lifting member based on a value acquired in advance, when the actual expansion fracture occurs due to the variation in the properties of the workpiece or the expansion piece, etc. There is a risk of remaining undivided areas. Therefore, the jacking amount may be set somewhat more than the above-mentioned proper jacking amount. This increase in the lift amount is estimated by the operator of the operating device by visual measurement, so experience or skill is required to obtain the optimum value that does not generate an undivided area and does not break the expansion piece.

The present invention has been made in view of such a problem, and an object of the present invention is to provide a thin-film adhesive that can divide a workpiece divided along a line to divide or divided along each wafer without leaving an undivided region, and suppress the occurrence of breakage of the expansion sheet sheet expansion device.

[Technical Means for Solving the Problem] The present invention relates to a sheet expanding device that expands the expanding sheet in a form of supporting the workpiece on a ring-shaped frame having an opening in the center via the expanding sheet, and divides the workpiece along the dividing starting point, Alternatively, the film-like adhesive is divided along each wafer, and the expansion sheet is adhered to the workpiece having the dividing starting point formed along a plurality of intersecting planned dividing lines, or the film-like adhesive adhered to the back surface of each divided wafer. On the back side of the agent, the sheet expansion device is provided with: annular frame fixing means having a support surface for supporting the annular frame of the workpiece unit, and fixing the annular frame placed on the support surface; The pressing part pushes the expansion piece between the inner circumference of the annular frame and the outer circumference of the workpiece fixed by the annular frame fixing means, so as to expand the expansion piece; the elastic wave detection sensor is after expanding the expansion piece , detecting elastic waves generated when the workpiece is broken along the starting point of division or when the film adhesive is broken along each wafer; and control means, wherein the control means includes: a memory part for recording along the starting point of division When the workpiece is completely broken or the film adhesive is completely broken along each wafer, the value of the output signal from the elastic wave detection sensor is based on the value, which is stored as a threshold value in advance. When breaking the workpiece or breaking the thin-film adhesive along each wafer, if the output signal from the elastic wave detection sensor does not reach the threshold value, it is considered that there is an unbroken area, and an error signal is output.

According to the sheet expansion device of the present invention, since the elastic wave when the workpiece or the film adhesive is well fractured is memorized as a threshold value in advance, the value of the output signal from the elastic wave detection sensor is compared with the threshold value during the expansion fracture. When it is equal to the threshold value, it can be determined that it is completely broken, so that the expansion piece can be brought into the most appropriate expansion state. In addition, by comparing the value of the output signal from the elastic wave detection sensor with the threshold value during the expansion fracture, it is possible to judge whether or not the unbroken area remains, so that the unbroken situation can be prevented.

[Effect of the Invention] According to the present invention, a sheet expanding device can be obtained, which can divide a workpiece divided along a planned dividing line or a film-like adhesive divided along each wafer without leaving an undivided region, and suppress the generation of expanded sheets. break.

Hereinafter, the sheet expansion device of the present embodiment will be described. FIG. 1 is a perspective view of the sheet expansion device according to the present embodiment. 2 and 3 are cross-sectional views showing the first aspect of the sheet expansion device, FIG. 4 is a cross-sectional view showing the second aspect of the sheet expansion device, FIG. 5 is a cross-sectional view showing the third aspect of the sheet expansion device, and FIG. 6 It is a sectional view showing the fourth aspect of the sheet expansion device. First, with reference to FIGS. 1-3, the structure of the sheet expansion apparatus common to the 1st to 4th forms is demonstrated. In addition, the sheet expansion device is not limited to this structure, and can be appropriately changed.

The sheet expansion device 1 shown in FIG. 1 holds the annular frame 11 constituting the workpiece unit 10, and divides the workpiece 13 by expanding the expansion sheet 12 stretched on the annular frame 11. A circular opening 14 covered with the expansion piece 12 is formed in the center of the annular frame 11 . The expansion piece 12 is fixed to the back side of the annular frame 11 in the peripheral region of the opening 14 , and is elastically deformable in the inner region of the opening 14 . The elastically deformable portion of the expansion piece 12 is adhered to the back surface of the workpiece 13 having a substantially disc shape. The outer diameter of the workpiece 13 is smaller than the inner diameter of the opening 14 of the annular frame 11 , and there is a radial gap between the outer circumference 13 a of the workpiece 13 and the inner circumference of the annular frame 11 (the inner edge of the opening 14 ).

A plurality of planned dividing lines 15 (refer to FIG. 1 ) intersecting in a lattice shape are provided on the surface of the workpiece 13 , and various elements (not shown) are formed in each region defined by the planned dividing lines 15 . In addition, inside the workpiece 13 , a modified layer 16 serving as a starting point for division is formed along the line to be divided 15 (see FIG. 2 ). In addition, the modified layer 16 refers to a region where the density, refractive index, mechanical strength, or other physical properties inside the workpiece 13 are different from those in the surroundings by irradiating a laser, and the intensity is lower than that of the surroundings. In this embodiment, the modified layer 16 is exemplified as the starting point for division, but the starting point for division may be a starting point for division if the strength of the workpiece 13 is low.

The sheet expansion device 1 includes frame fixing means 20 for holding the annular frame 11 of the workpiece unit 10 . The frame fixing means 20 includes a support base 21 having a quadrangular shape in plan view, and a cover plate 23 that covers the support surface 22 of the support base 21 from above. The support table 21 is supported from the lower side by a plurality of support legs 24 . Circular openings 25 and 26 having substantially the same diameter as the opening 14 of the annular frame 11 are formed in the centers of the support base 21 and the cover plate 23 .

As shown in FIG. 2 , the workpiece unit 10 places the annular frame 11 on the support surface 22 with the workpiece 13 facing upward. In this state, when the cover plate 23 is installed on the support table 21, the annular frame 11 is held by the support surface 22 of the support table 21 and the cover plate 23, and the elastically deformable elastic deformation of the expansion piece 12 is maintained. Parts and workpiece 13 are located inside circular openings 25,26. The cover plate 23 is fixed to the support base 21 by a jig or the like not shown, whereby the annular frame 11 is firmly held in a fixed state.

The lift table 30 is provided in the center of the sheet expansion apparatus 1 . The lift table 30 has a substantially circular outer peripheral shape in plan view, and its diameter is smaller than the inner diameter of the circular openings 25 and 26 of the frame fixing means 20 . The lift table 30 is supported from the lower side via a plurality of ball screw mechanisms 31 . Each ball screw mechanism 31 includes a motor 31a, a ball screw 31b extending upward from the motor 31a and rotated by the motor 31a, a nut 31c screwed to the ball screw 31b, and a support leg 31d to which the nut 31c is coupled. The nut 31c and the support leg 31d restrict the rotation about the axis of the ball screw 31b, and the lift table 30 is fixed to the upper end of the support leg 31d. Therefore, when the motor 31a of each ball screw mechanism 31 is driven and the ball screw 31b is rotated, the nut 31c and the support leg 31d move up and down, and the lift table 30 is raised and lowered. The lift table 30 can be moved to a standby position below the support table 21 and a jack-up position above the support table 21 (see FIG. 3 ). When moving from the standby position to the jack-up position, it passes through the circular openings 25 and 26 Inside, the expansion piece 12 is pressed from below to above. By this pressing, the expansion piece 12 is expanded. That is, the expansion means for expanding the expansion piece 12 is constituted by the lift table 30 , which is a pressing portion that presses the expansion piece 12 , and the ball screw mechanism 31 for raising and lowering the lift table 30 .

On the outer edge of the lift table 30, a plurality of rollers 33 are provided over the entire circumference. As shown in FIG. 2 , each of the plurality of rollers 33 is rotatably supported in a stepped portion 34 formed on the outer edge of the lift table 30 with the shaft portion 33 a as the center. When the lift table 30 ascends, each roller 33 contacts the lower surface of the expansion piece 12 and presses it. The position where each roller 33 presses the expansion piece 12 is an area between the inner circumference of the annular frame 11 (the inner edge of the opening 14 ) and the outer circumference 13 a of the workpiece 13 .

In the above-mentioned sheet expanding device 1, if the motor 31a of the ball screw mechanism 31 is driven to slowly move the lift table 30 upward from the standby position, as shown in FIG. 26 The lower surface of the expansion sheet 12 inside. If the lift table 30 is moved further upwards, the sticking area of the workpiece 13 of the expansion sheet 12 will be pushed up, and the expansion sheet 12 will be pulled by the force in the direction indicated by the arrow F1 in FIG. 3 . Thereby, the adhesive region of the workpiece 13 of the expansion piece 12 is expanded radially. Then, an external force in the diameter-expanding direction acts on the workpiece 13 to generate cracks in the thickness direction of the workpiece 13 starting from the modified layer 16 ( FIG. 2 ) formed in the workpiece 13 . By applying an external force to the front and back of the workpiece 13 , the cracks penetrate the workpiece 13 , and are divided into individual wafers C ( FIG. 3 ) along the dividing line 15 ( FIG. 1 ). By using the ball screw mechanism 31 as the expansion means, the lifting and lowering of the lift table 30 can be adjusted with fine precision and high precision, or the lifting and lowering speed of the lift table 30 can be changed to appropriately manage the fracture speed of the workpiece 13 .

As shown in FIG. 3 , when the expansion piece 12 is pushed up by the lift table 30 to expand, the angle of the expansion piece 12 changes at the outer edge of the lift table 30 . By arranging the plurality of rollers 33 , the friction of the expansion piece 12 on the outer edge portion of the lift table 30 can be suppressed, and the expansion can be made smoothly.

After the division of the workpiece 13 is completed, the motor 31a of the ball screw mechanism 31 is driven, and the lift table 30 is lowered to the standby position. Next, the fixing of the annular frame 11 by the frame fixing means 20 is released, and the workpiece unit 10 is removed from the sheet expanding device 1 .

In the expansion and fracture of the sheet expansion apparatus 1 as described above, until the workpiece 13 is completely divided into all the wafers C as shown in FIG. 3 , it is necessary to move the lift table 30 upward. If the lifting amount of the elevating table 30 with respect to the expansion piece 12 is insufficient, an undivided region that has not been properly divided remains in the region along the line 15 to be divided into the workpiece 13 . On the other hand, when the lifting amount of the lift table 30 is too large, the expansion sheet 12 may not be resistant to expansion and may be broken. Therefore, it is generally required to appropriately set the jacking amount of the lift table 30 . However, since the external force required for dividing without leaving an undivided region differs subtly according to the properties of the expansion piece 12 or the workpiece 13 , it is difficult to set the jacking amount of the lift table 30 in the same way. In this embodiment, the lifting amount of the lift table 30 can be easily managed according to the divided state of the workpiece 13, and the characteristics thereof will be described below.

The sheet expansion apparatus 1 of the first aspect shown in FIGS. 2 and 3 includes a control means 40 , a notification means 41 , and an elastic wave detection sensor 50 . The control means 40 collectively controls the sheet expansion apparatus 1, and is constituted by a processor, a memory, and the like that execute various processes. The notification means 41 notifies an error state to be described later by means of screen display, light emission, sound, and the like, and is composed of a display screen, a light-emitting unit, a speaker, and the like provided in the sheet expansion apparatus 1 .

The elastic wave detection sensor 50 is constituted by, for example, an AE sensor (Acoustic Emission Sensor; acoustic emission sensor) having a function of detecting elastic waves. Specifically, the elastic wave detection sensor 50 includes an ultrasonic oscillator (not shown) fixed inside a fixing flange (not shown). Ultrasonic oscillators are made of materials such as barium titanate (BaTiO ₃ ), lead zirconate titanate (Pb(Zi, Ti) O ₃ ), lithium niobate (LiNbO ₃ ), and lithium tantalate (LiTaO ₃ ), and have The property of converting vibration into voltage (vibration signal).

As shown in FIGS. 2 and 3 , the elastic wave detection sensor 50 is mounted on the lift table 30 , and particularly, the elastic wave detection sensor 50 is disposed in the lift table 30 at a position directly below the roller 33 . As shown in FIG. 3 , when the expansion sheet 12 is expanded, along with the fracture of the workpiece 13 , strain energy is released as an elastic wave. The elastic wave generated by the division of the workpiece 13 propagates to the elastic wave detection sensor 50 via the roller 33 contacting the expansion sheet 12 and the lift table 30 supporting the roller 33 through the shaft portion 33a. The elastic wave detection sensor 50 detects the propagating elastic wave, and outputs an output signal to the control means 40 .

The output signal detected by the elastic wave detection sensor 50 is converted into an output voltage by a signal processing unit (not shown), and then input to the control means 40 . The control means 40 includes a memory unit 40a, a comparison unit 40b, and a drive control unit 40c. The memory unit 40a is composed of the above-mentioned memory, and stores in advance, as threshold data, the output signal of the elastic wave detection sensor 50 indicating the state in which the workpiece 13 has been divided. The comparison part 40b compares the threshold value stored in the memory part 40a with the output signal from the elastic wave detection sensor 50, and determines whether the output signal reaches the threshold value when the sheet expansion device 1 is undergoing expansion and fracture. The drive control unit 40 c is a portion that controls the operation of the motor 31 a of the ball screw mechanism 31 . According to the determination result of the comparison part 40b, the drive control part 40c controls the continuation or stop of the operation of the motor 31a.

More specifically, the threshold value is set based on the output signal of the elastic wave detection sensor 50 when the workpiece 13 is well fractured (divided) into each wafer C without leaving an undivided region. FIG. 7 is a graph showing an example of the detection result of the elastic wave detection sensor 50 . In the graph of FIG. 7 , the vertical axis represents the AE value output by the elastic wave detection sensor 50 , and the horizontal axis represents the elapsed time, which is the result of detecting the elevating stage 30 after it started to rise until it stopped. When the workpiece 13 is broken and an elastic wave is generated, the AE value increases. The output waveform W1 of the AE value shown in FIG. 7 shows that the workpiece 13 is completely broken into the respective wafers C without leaving undivided regions. Based on this output waveform W1, a threshold value is set. For example, the threshold value is set as the cumulative output of the AE value represented by the area within the region drawn by the output waveform W1. When the threshold value is set, it is easy to determine when the division is completed by increasing the lift-up amount of the lift table 30 . The threshold value thus obtained is stored in the memory unit 40a.

Next, the workpiece unit 10 supporting the undivided workpiece 13 is set on the sheet expanding device 1, and the motor 31a of the ball screw mechanism 31 is driven to raise the lift table 30 at a predetermined speed, while monitoring the elastic wave detection sense by the control means 40. The output signal of the detector 50. The control means 40 compares the threshold value stored in the memory unit 40a with the output signal from the elastic wave detection sensor 50 by the comparison unit 40b, and performs predetermined processing or operation management. Specifically, the cumulative output of the output waveform W1 of FIG. 7 memorized as the threshold value (the area in the region depicted by the output waveform W1 ) and the output waveform of the AE value of the elastic wave detection sensor 50 actually obtained The accumulated outputs of 2 (in the area within the region delineated by the output waveform) are compared, and when these accumulated outputs are equal, it can be determined that the undivided region does not remain and the workpiece 13 is completely broken. On the other hand, as shown in the output waveform W2 shown in FIG. 7 , when the cumulative output of the AE value (the area within the region delineated by the output waveform W2 ) does not reach the cumulative output of the output waveform W1 which is the threshold value, it can be determined as a workpiece 13 is insufficiently fractured, leaving unsegmented areas.

As processing and operation management based on the above comparison results, for example, when the output signal from the elastic wave detection sensor 50 reaches a threshold value, the drive control unit 40c operates the motor 31a of the ball screw mechanism 31 (elevating table 30 jacking action) to stop. Since it can be determined that the workpiece 13 is completely broken at the same time as the output signal from the elastic wave detection sensor 50 and the threshold value, etc., at this point, the amount of lifting of the expansion piece 12 is sufficient, and it is determined that the lift table 30 can be lifted. stop. In addition, since the lift-up amount of the lift table 30 at this point is the minimum necessary, an excessive load is not applied to the expansion piece 12, and breakage can be prevented. That is, the pressing of the expansion piece 12 can be completed with the most appropriate amount of lifting. Furthermore, it is also possible to control such that some detection errors are estimated, and after a predetermined time (predetermined driving amount) has elapsed, rather than the moment when the output signal from the elastic wave detection sensor 50 reaches the threshold value, the ball screw mechanism 31 can be controlled. The motor 31a is stopped.

In addition, an experiment or the like is performed in advance to obtain a value of the lifting amount suitable for the type of the workpiece 13 or the expansion piece 12 or the processing conditions as the reference lifting amount, and in the dividing step of a certain workpiece 13, the lifting table 30 is moved upward to the reference value. At the time of the lifting amount, it can also be judged whether or not the division of the workpiece 13 has been completed by comparing the threshold value stored in the memory unit 40a with the output signal from the elastic wave detection sensor 50 . Although the lift table 30 is moved upward to the reference lift amount, the output signal from the elastic wave detection sensor 50 is the output waveform W2 shown in FIG. . In this case, an error signal indicating that there is an unbroken area is output from the comparison unit 40b. As soon as the error signal is output, the control means 40 performs predetermined error processing.

In error handling, the notification means 41 can be used to perform notification of the error state. Upon receiving the notification of the error state, the operator of the operation piece expansion device 1 will adjust the jacking amount of the lift table 30 and the like. At this time, the control means 40 may continue to compare the output signal of the elastic wave detection sensor 50 with the threshold value, and continue to determine and notify whether there is an unbroken area. In this way, based on the detection result of whether or not the undivided area actually remains, rather than estimation by the operator's visual measurement, the lifting amount of the lift table 30 can be adjusted with high accuracy. In addition, as error processing, the control means 40 may automatically adjust the jacking amount of the lift table 30 .

Furthermore, if the expansion sheet 12 is damaged due to some reasons, it can also be detected by the control means 40 and the elastic wave detection sensor 50 . The elastic wave detection sensor 50 is arranged at a position close to the roller 33 in contact with the expansion sheet 12 , and elastic waves generated by the breakage of the expansion sheet 12 easily propagate to the elastic wave detection sensor 50 . Since the elastic wave generated when the expansion sheet 12 is broken is different from the waveform or the like of the elastic wave generated when the workpiece 13 is generally broken due to expansion fracture, it can be discriminated. When the elastic wave detection sensor 50 detects an abnormal elastic wave different from the breakage of the workpiece 13 , the control means 40 can determine that the expansion sheet 12 is broken. Alternatively, the elastic wave when the expansion sheet 12 is broken is detected in advance by the elastic wave detection sensor 50 and stored in the memory unit 40a, and the comparison unit 40b compares the stored data with the detected abnormal elastic wave to determine Whether the expansion sheet 12 is damaged. In any case, when it is determined that the expansion piece 12 is broken, the control means 40 preferably informs the operator via the notification means 41 or stops the operation of the motor 31a of the ball screw mechanism 31 to prevent the damage from expanding.

The position at which the elastic wave detection sensor is installed or the type of the elastic wave detection sensor may be different from those of the first aspect described above. As a modification example, the second, third, and fourth aspects of the sheet expansion device are used. shown in Figures 4 to 6. In each of the second, third, and fourth forms, elements other than the elastic wave detection sensor are common to the above-described first form, and the description of the common elements is omitted.

The sheet expansion device 1 of the second aspect shown in FIG. 4 is one in which the elastic wave detection sensor 51 is in contact with the expansion sheet 12 . The elastic wave detection sensor 51 is located in the vicinity of the center of the workpiece 13 in the radial direction (horizontal direction when the vertical direction in FIG. 4 is the vertical direction), and contacts the expansion sheet 12 from the lower surface side.

The elastic wave detection sensor 51 is supported from the lower side by the ball screw mechanism 35 . The ball screw mechanism 35 includes a motor 35a, a ball screw 35b that extends upward from the motor 35a and is rotated by the motor 35a, a nut 35c that is screwed to the ball screw 35b and restricts rotation, and a support leg 35d connected to the nut 35c. The upper end of the elastic wave detection sensor 51 is supported. When the motor 35a is driven and the ball screw 35b is rotated, the nut 35c and the support leg 35d move up and down, and the elastic wave detection sensor 51 is moved up and down. When the elevating table 30 moves up and down by the drive of the ball screw mechanism 31 , the ball screw mechanism 35 is driven and controlled so that the elastic wave detection sensor 51 also moves up and down in conjunction, and the elastic wave detection sensor 51 is kept in contact with the expansion sheet 12 . status. Furthermore, the elastic wave generated by the fracture of the workpiece 13 propagates to the elastic wave detection sensor 51 through the expansion sheet 12 to which the workpiece 13 is adhered.

In the sheet expansion apparatus 1 of the third aspect shown in FIG. 5 , the elastic wave detection sensor 52 is arranged above the workpiece 13 . The elastic wave detection sensor 52 is separated from the workpiece 13 , and the elastic wave generated by the breakage of the workpiece 13 reaches the elastic wave detection sensor 52 as a sound wave propagating in the air. Unlike the above-mentioned AE sensor, the elastic wave detection sensor 52 is composed of a microphone capable of detecting sound waves of lower frequencies including an audible frequency band, and converts the vibration of the air generated when the workpiece 13 is broken into an electrical signal After that, it is output to the control means 40 .

In order to stabilize the detection conditions of the elastic wave detection sensor 52 , it is desirable to keep the distance between the workpiece 13 and the elastic wave detection sensor 52 constant when the lift table 30 is jacked up. That is, the elastic wave detection sensor 52 may be moved up and down in conjunction with the lift table 30 .

The sheet expansion apparatus 1 of the fourth aspect shown in FIG. 6 is provided with an elastic wave detection sensor 53 not on the lift table 30 but on the side of the frame fixing means 20 . The elastic wave detection sensor 53 is inserted into a hole formed in the cover plate 23 and abuts against the annular frame 11 of the workpiece unit 10 . The elastic wave generated when the workpiece 13 is broken propagates from the expansion sheet 12 to the elastic wave detection sensor 53 via the annular frame 11 .

The elastic wave detection sensors 51 and 53 of the respective aspects of FIGS. 4 and 6 may be constituted by AE sensors, similarly to the elastic wave detection sensor 50 of the first aspect ( FIGS. 2 and 3 ) described above. By using the AE sensor, high-precision detection that is not easily affected by ambient noise and the like can be performed. For the elastic wave detection sensors 50 , 51 and 53 , the propagation paths of elastic waves differ from each other depending on the contacted objects and even the sensors. Different AE sensors suitable for each condition can be appropriately selected and used.

As described above, in the present embodiment, the elastic wave generated by the fracture of the workpiece 13 is detected, and the expansion of the expansion sheet 12 is performed while comparing with the threshold value of the elastic wave indicating the good fracture of the workpiece 13, and based on the comparison As a result, the output of an error signal, the operation control of the lift table 30, and the like are performed. Thereby, the expansion state of the most appropriate expansion piece 12 can be easily set, without relying on the operator's difficult management such as visual adjustment.

Various workpieces such as semiconductor element wafers, optical element wafers, package substrates, semiconductor substrates, inorganic material substrates, and oxide wafers can be used as the workpieces 13 to be divided and processed by the sheet expansion apparatus 1 of the present embodiment. As the semiconductor element wafer, a silicon wafer or a compound semiconductor wafer after element formation can be used. As the optical element wafer, a sapphire wafer or a silicon carbide wafer after element formation can be used. In addition, as a package substrate, a CSP (Chip Size Package) substrate can be used, as a semiconductor substrate, silicon, gallium arsenide, etc. can be used, and as an inorganic material substrate, sapphire, ceramic, glass etc. In addition, as the oxide wafer, lithium tantalate and lithium niobate can be used after element formation or before element formation.

In addition, the object of the division|segmentation process of the sheet|seat expansion apparatus of this invention is not limited to the workpiece|work mentioned above. For example, a film-like adhesive such as DAF (Die Attach Film) to be adhered to the back surface of each wafer obtained by dividing the workpiece may be used as the object of division. The thin film adhesive may be divided together with the workpiece when the workpiece is divided into individual wafers, or only the thin film adhesive may be divided after the division into the individual wafers.

In addition, in the present embodiment, the sheet expanding device 1 of the type in which the lifting table 30 (the portion where the workpiece 13 is adhered among the expanding sheets 12 ) is moved up and down with respect to the frame fixing means 20 (ring frame 11 ) is exemplified. Conversely, it can be applied to a sheet expanding device of a type that moves the annular frame 11 up and down without moving the workpiece 13 . Specifically, the part corresponding to the elevating table 30 is changed to a support table that supports the expansion piece 12 and the workpiece 13 at a predetermined position without raising and lowering, and the part corresponding to the frame fixing means 20 is changed to an elevating part that can move up and down. When expanding and breaking, the lifting portion holding the annular frame 11 is moved downward. At this time, although the support table itself does not move, the expansion piece 12 is expanded while being pressed against the support table by the pulling force accompanying the downward movement of the annular frame 11 . Therefore, like the lift table 30 of the above-described embodiment, the support table functions as a pressing portion that presses the area where the workpiece 13 of the expansion sheet 12 is adhered.

When the sheet expanding device of the type in which the annular frame 11 is moved up and down without moving the workpiece 13 is applied to the form shown in FIG. 4 or FIG. 5 , since the vertical position of the workpiece 13 does not change, a sense of elastic wave detection can be obtained. The measuring devices 51 and 52 are configured so that they do not move up and down.

The sheet expansion apparatus to which the present invention is applied may be used alone, or may be used as a part of a cluster module system in which a plurality of processing units can be freely combined.

In addition, although each embodiment of this invention was described, as another embodiment of this invention, the above-mentioned embodiment and modification example may be combined in whole or in part.

In addition, the embodiment of the present invention is not limited to the above-described embodiment and modification examples, and various changes, substitutions, and deformations can be made without departing from the spirit of the technical idea of the present invention. Furthermore, if the technical idea of the present invention can be realized by another method due to technological progress or other derived technologies, this method can also be used. Therefore, the scope of the patent application covers all the embodiments that can be included in the scope of the technical idea of the present invention.

[Industrial Applicability] As described above, the present invention has a sheet expansion device that expands an expansion sheet and divides a workpiece or a film-like adhesive, and has the ability to reliably divide without leaving an undivided region, and to suppress the occurrence of expansion. The effect of breaking the sheet is a sheet expanding device that contributes to improved productivity or high-precision division processing.

1‧‧‧Piece expansion device 10‧‧‧Workpiece unit 11‧‧‧Ring frame 12‧‧‧Expanding piece 13‧‧‧Workpiece 13a‧‧‧Outer periphery 14‧‧‧Opening 15‧‧‧Planning line for dividing 16‧ ‧‧Modified layer 20‧‧‧Frame fixing means 21‧‧‧Support table 22‧‧‧Support surface 23‧‧‧Cover plate

24: Support feet

25: round opening

26: Round opening

30: Lifting table (expansion means, pressing part)

31: Ball screw mechanism (expansion means)

33: Roller (expansion means, pressing part)

34: Step part

35: Ball screw mechanism

40: Control Means

40a: Memory Department

40b: Comparison Section

40c: Drive Control Department

41: Notification Means

50: Elastic wave detection sensor

51: Elastic wave detection sensor

52: Elastic wave detection sensor

53: Elastic wave detection sensor

C: wafer

FIG. 1 is a perspective view of the sheet expansion device according to the present embodiment. Fig. 2 is a cross-sectional view showing the sheet expansion device of the first aspect. 3 is a cross-sectional view showing a state in which the workpiece is divided by the sheet expanding device of the first aspect. FIG. 4 is a cross-sectional view showing the sheet expansion device of the second aspect. Fig. 5 is a cross-sectional view showing the sheet expansion device of the third aspect. Fig. 6 is a cross-sectional view showing the sheet expansion device of the fourth aspect. FIG. 7 is a graph showing the detection result of the elastic wave detection sensor.

1‧‧‧Sheet expansion device

10‧‧‧Workpiece unit

11‧‧‧Ring frame

12‧‧‧Expansion

13‧‧‧Workpiece

13a‧‧‧Peripheral

14‧‧‧Opening

16‧‧‧Modified layer

20‧‧‧Frame fixing means

21‧‧‧Support

22‧‧‧Support surface

23‧‧‧Cover

24‧‧‧Support feet

25‧‧‧Circular opening

26‧‧‧Circular opening

30‧‧‧Lifting table (expansion means, pressing part)

31‧‧‧Ball screw mechanism (expansion means)

31a‧‧‧motor

31b‧‧‧ball screw

31c‧‧‧nut

31d‧‧‧Support feet

33‧‧‧Roller (expanding means, pressing part)

33a‧‧‧Shaft

34‧‧‧Steps

40‧‧‧Control means

40a‧‧‧Memory Department

40b‧‧‧Comparison

40c‧‧‧Drive control section

41‧‧‧Means of notification

50‧‧‧Elastic wave detection sensor

Claims (1)

A sheet expansion device that expands the expansion sheet in the form of supporting a workpiece on a ring-shaped frame with an opening in the center via the expansion sheet, and divides the workpiece along the starting point of division, or divides the film along the respective wafers The expansion sheet is adhered to the workpiece with the starting point of division formed along the intersecting multiple planned division lines, or to the back of the film-shaped adhesive attached to the back of each wafer after division, the sheet expansion device comprising: an annular frame fixing means having a support surface for supporting the annular frame of the workpiece unit, and fixing the annular frame placed on the support surface; expanding means for pressing the annular frame with a pressing portion the expansion piece between the inner circumference of the annular frame and the outer circumference of the workpiece fixed by the annular frame fixing means, so as to expand the expansion piece; the elastic wave detection sensor detects the edge of the expansion piece after expanding the expansion piece elastic waves generated when the workpiece is broken along the division starting point or when the thin film adhesive is broken along the respective wafers; and a control means, wherein the control means includes: a memory portion which is arranged along the division starting point When the workpiece is completely broken or the film adhesive is completely broken along each wafer, the value of the output signal from the elastic wave detection sensor is based on the reference value, which is stored in advance as a threshold value. After expanding the expansion sheet, When the workpiece is broken along the dividing starting point or when the film adhesive is broken along each wafer, when the output signal from the elastic wave detection sensor does not reach the threshold value, it is considered that there is an unbroken area and Error signal is output.

Images