JP2012044117A - Laminated wafer inspection device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a laminated wafer inspection device capable of preventing variations in inspection accuracy and reducing inspection cost and time by automating peeling inspection.SOLUTION: The laminated wafer inspection device comprises: tape supply means for supplying adhesive tape to be pasted to a surface of a laminated wafer; tape collection means for collecting the adhesive tape peeled from the surface of the laminated wafer; wafer holding means for holding the laminated wafer on the pasting face side of the adhesive tape stretched between the tape supply means and the tape collection means; tape pasting means for pasting the adhesive tape to the surface of the laminated wafer by moving from a pasting start position to a pasting end position while pressing the adhesive tape against the surface of the laminated wafer; tape peeling means for peeling the adhesive tape pasted to the surface of the laminated wafer by moving from a peeling start position to a peeling end position; and tension adjustment means for adjusting the tension of the adhesive tape.

Description

  The present invention relates to an apparatus used for inspecting a bonded wafer, and more particularly to an apparatus used for inspecting the presence or absence of a bonding failure portion of a bonded wafer.

  Conventionally, in a bonded wafer, if there is a bonding failure portion at the bonding interface, the active layer easily peels off during the device manufacturing process at the portion where the bonding failure portion exists, and the bonding failure portion is It is known to cause device failure and dust generation.

  For this reason, various methods for inspecting the presence or absence of a bonding failure portion of a bonded wafer have been proposed for the purpose of improving the yield in the device manufacturing process.

  Specifically, the surface of the active layer is used as a method for inspecting the presence or absence of a bonding failure of a bonded wafer formed by thinning the active layer substrate bonded to the support substrate and forming the active layer on the support substrate. There has been proposed a method (peeling inspection) in which an adhesive tape is attached to at least a part of the film and then the adhesive tape is peeled off (see, for example, Patent Document 1). According to this peeling inspection, when there is a poorly bonded portion at the bonding interface, the active layer located above the poorly bonded portion adheres to the adhesive tape and is removed. By observing the surface of the bonded wafer, the presence or absence of a defective bonding portion can be inspected.

JP 2010-21408 A

  Here, in the above-described conventional peeling inspection, the adhesive tape attaching method and the peeling method are not particularly studied, and as a simple experimental level inspection method for manually attaching and removing the adhesive tape. It was only used.

  For this reason, when the bonded wafer is peeled, for example, the pressure of the adhesive tape against the surface of the bonded wafer when the adhesive tape is applied becomes non-uniform, and air bubbles are mixed between the bonded wafer and the adhesive tape. In some cases, it is difficult to detect a poorly bonded portion immediately below a portion where bubbles exist. In addition, when the adhesive tape attached to the surface of the bonded wafer is peeled off, the peel force varies, and in fact there are errors such as being not detected even though there is a poorly bonded part at the bonding interface. In some cases, detection occurred.

  Accordingly, the conventional peeling inspection cannot always be inspected under stable inspection conditions, and the inspection accuracy varies, so that there is a problem that it is difficult to apply to the total inspection of bonded wafers. Further, since the adhesive tape is attached and peeled manually, there is a problem that inspection takes time and the inspection cost increases.

  Therefore, the present inventors recalled that automating the peeling inspection to suppress the variation in inspection accuracy and reduce the time and cost required for the inspection. The present invention was completed by earnestly studying the influence on the effect.

That is, this invention aims to solve the above-mentioned problem advantageously, and the bonded wafer inspection apparatus of the present invention attaches the adhesive tape to the surface of the bonded wafer, and then attaches the adhesive tape. A bonded wafer inspection apparatus for inspecting the presence or absence of a defective bonding portion by peeling from the surface of the bonded wafer, the tape supply means for supplying an adhesive tape to be bonded to the surface of the bonded wafer, and the bonding A tape collecting means for collecting the adhesive tape peeled off from the surface of the bonded wafer, and holding the bonded wafer on the adhesive tape attaching surface side stretched between the tape supply means and the tape collecting means. Wafer holding means is disposed so as to be able to reciprocate between a sticking start position and a sticking end position, and the adhesive tape is attached to the surface of the bonded wafer. The adhesive tape is attached to the surface of the bonded wafer by moving from the sticking start position to the sticking end position while pressing the tape, and reciprocating between the peeling start position and the peeling end position. It is arranged so as to be movable, moves from the peeling start position to the peeling end position, and peels off the adhesive tape attached to the surface of the bonded wafer, and adjusts the tension of the adhesive tape and the tension of the adhesive tape. And tension adjusting means. Thus, if the tape attaching means, the tape peeling means, and the tension adjusting means are provided, the adhesive tape can be attached or peeled at a predetermined speed while applying a predetermined tension to the adhesive tape. Further, it is possible to suppress the occurrence of variations in inspection accuracy by performing a peeling inspection under stable inspection conditions. Also, by providing a tape supply means, a tape recovery means, a wafer holding means, a tape attaching means, a tape peeling means and a tension adjusting means, these means can be linked to automate the peeling inspection. The time and cost required for the inspection can be reduced. In addition, since the adhesive tape can be applied to the surface of the bonded wafer while pressing the adhesive tape with the tape applying means, it is possible to prevent the adhesive tape from pressing unevenly against the bonded wafer surface, resulting in poor bonding. The active layer located on the upper part of the part can be reliably peeled off. Therefore, if this bonded wafer inspection apparatus is used, a total inspection of bonded wafers can be performed.
According to the study by the present inventors, the poorly bonded portion where the active layer peels off by peeling test includes both non-bonded portions (void defects) such as voids and portions where the bonding strength of the bonding is weak. It is clear that it is included.

  Here, the bonded wafer inspection apparatus of the present invention is disposed so as to face the wafer holding means with the adhesive tape interposed therebetween, and the bonded wafer is bonded via the adhesive tape attached to the surface of the bonded wafer. It is preferable to include a pressing means for pressing at least the outer peripheral portion of the wafer. Since a poorly bonded part is likely to occur especially at the outer peripheral part of the bonded wafer, if a pressure means is provided and the adhesive tape is securely applied to the outer peripheral part of the wafer, the defectively bonded part can be detected with higher accuracy. Because it can. In the present invention, the “outer peripheral portion” refers to a portion from the outermost periphery of the wafer to 5 mm toward the wafer center.

  In the bonded wafer inspection apparatus of the present invention, it is preferable that the wafer holding unit has a rotation mechanism that rotates the bonded wafer around the center position of the bonded wafer held. This is because if the rotation mechanism is provided, the adhesive tape can be attached and peeled from various directions to the same wafer, and the void defect detection accuracy can be further enhanced. In addition, when two wafers are stacked and bonded together, most of the bonding failure portions generated at the bonding interface occur near the outer peripheral portion on the bonding end side opposite to the bonding start side. For this reason, if a rotation mechanism is provided, it becomes possible to inspect only the region on the bonding end side where the bonded wafer is rotated and a defective bonding portion is likely to occur, thereby reducing the inspection time and the amount of adhesive tape used. You can also.

  Furthermore, in the bonded wafer inspection apparatus of the present invention, it is preferable that the tape peeling means has a reaction force measuring mechanism for measuring a reaction force of the adhesive tape. If a reaction force measurement mechanism is provided, the peel force applied to the surface of the bonded wafer can be confirmed using the measured reaction force, so optimization of the peel conditions and the occurrence of variations in detection accuracy This is because it is possible to suppress this.

  The bonded wafer inspection apparatus of the present invention preferably has a surface inspection means for observing the surface of the bonded wafer after the adhesive tape is peeled off. This is because if surface inspection means is provided, it is possible to determine the presence or absence of a defective bonding portion automatically and with high accuracy.

  According to the bonded wafer inspection apparatus of the present invention, it is possible to automate the peeling inspection to suppress the occurrence of variations in inspection accuracy, and to reduce the time and cost required for the inspection.

It is explanatory drawing which shows the structure of the typical bonded wafer inspection apparatus according to this invention. It is explanatory drawing which shows a part of a mode that a bonded wafer is test | inspected using the bonded wafer inspection apparatus shown in FIG. 1, (a) shows a tape sticking process, (b) shows a press process, c) shows a tape peeling process, (d) shows a rotation process. It is explanatory drawing which shows a mode that the outer peripheral part of a bonded wafer is pressed using the typical press means which comprises the test | inspection apparatus of this invention. It is explanatory drawing which shows a mode that the bonding wafer is rotated and the sticking direction of the adhesive tape with respect to a bonded wafer is changed 4 times, (a) shows the case where an adhesive tape is affixed on the whole wafer surface, b) shows a case where an adhesive tape is applied to the surface of the half of the wafer. It is explanatory drawing which shows the structure of the other bonded wafer inspection apparatus according to this invention. It is explanatory drawing which shows a part of a mode that a bonded wafer is test | inspected using the bonded wafer inspection apparatus shown in FIG. 5, (a) shows a tape sticking process, (b) shows a press process, c) shows a tape peeling process, (d) shows a rotation process.

  Embodiments of the present invention will be described below with reference to the drawings. The bonded wafer inspection apparatus of the present invention is used for checking for the presence or absence of a bonding failure portion of a bonded wafer. In the bonded wafer inspection apparatus of the present invention, after the adhesive tape is applied to the surface of the bonded wafer, when the adhesive tape is peeled off from the surface of the bonded wafer, the portion where the void defect exists and the bonded wafer are bonded. Use the fact that the upper part of the bonding interface with weak bonding strength (that is, the bonding failure portion) adheres to the adhesive tape and is peeled and removed from the bonded wafer, and checks for the presence of bonding failure (peeling inspection). To do. That is, in the bonded wafer inspection apparatus of the present invention, whether or not there is a part removed on the surface of the bonded wafer after peeling the adhesive tape, or whether the removed wafer part is attached to the adhesive tape. Based on whether or not, a defective bonding portion is detected.

  In the bonded wafer inspection apparatus of the present invention, since the portion where the bonding defect exists adheres to the adhesive tape and is peeled and removed, the bonded wafer is inspected by the inspection apparatus of the present invention. The wafer is a wafer in which a thin wafer (active layer) that can be peeled and removed with an adhesive tape is bonded to a support wafer. Specifically, as the bonded wafer to be inspected by the inspection apparatus of the present invention, for example, a bonded wafer obtained by thinning the active layer bonded on the support wafer to about 50 μm or less can be exemplified. . In the bonded wafer inspection apparatus of the present invention, an inspection is performed by attaching an adhesive tape to the thin wafer side surface of the bonded wafer.

  1 and 2 show a first embodiment of the bonded wafer inspection apparatus of the present invention. A bonded wafer inspection apparatus 10 shown in FIG. 1 includes a tape supply roller 12 as a tape supply unit that supplies an adhesive tape 15 to be bonded to the surface of a bonded wafer 11, and an adhesive tape peeled off from the surface of the bonded wafer 11. A tape collecting roller 13 as a tape collecting means for collecting 15, a wafer holding stage 16 as a wafer holding means for holding a bonded wafer, and a tape attaching means for attaching the adhesive tape 15 to the surface of the bonded wafer 11. As a reaction force measuring mechanism for measuring the reaction force of the adhesive tape 15, the peeling rollers 18 A and 18 B as tape peeling means for peeling the adhesive tape 15 attached to the surface of the bonded wafer 11. The load cell 18C is bonded to the surface of the bonded wafer 11. And a pressing jig 19 as a pressing means for pressing the outer peripheral portion of the mating wafer 11 bonded through the adhesive tape 15. The bonded wafer inspection apparatus 10 includes an image processing apparatus (not shown) as surface inspection means for observing the wafer surface.

  In the bonded wafer inspection apparatus 10, the adhesive tape 15 includes a plurality of (five in FIG. 1 and FIG. 2) swing rollers 14 </ b> A, 14 </ b> B, 14 </ b> C, 14 </ b> D, between the tape supply roller 12 and the tape collection roller 13. 14E is stretched. In the bonded wafer inspection apparatus 10, the swing rollers 14A and 14C function as tension adjusting means for adjusting the tension of the adhesive tape 15 to be constant. Further, a separator (release paper) 20 for preventing the adhesive surface from being dried and maintaining the adhesive force is attached to the adhesive surface of the adhesive tape 15 (adhesive surface attached to the bonded wafer 11). The separator 20 is peeled off from the adhesive tape 15 before the adhesive tape 15 is attached to the bonded wafer 11, and is recovered by the separator recovery roller 21 via the swing roller 14F.

  The bonded wafer 11 is a wafer in which a thin wafer capable of being peeled and removed by the adhesive tape 15 is bonded to the support wafer. For example, as shown in FIG. The active layer 11 </ b> B is laminated on the substrate.

  The tape supply roller 12 and the tape collection roller 13 are rotatably supported, and the rotation speed of the tape supply roller 12 and the tape collection roller 13 can be adjusted by a rotation speed adjuster (not shown).

  The swing rollers 14 </ b> A to 14 </ b> F change the extending direction of the adhesive tape 15 and the separator 20, and are supported so as to be able to translate (swing) and rotate. In the bonded wafer inspection apparatus 10, the swing roller 14 </ b> A is particularly used as a tension adjusting unit that moves in parallel when the adhesive tape 15 is bonded to the surface of the bonded wafer 11 and adjusts the tension of the adhesive tape 15 to be constant. The swing roller 14 </ b> C functions as a tension adjusting unit that moves in parallel when the adhesive tape 15 is peeled from the surface of the bonded wafer 11 and adjusts the tension of the adhesive tape 15 to be constant. Further, the swing roller 14E can move in a direction substantially parallel to the surface of the bonded wafer 11 in FIGS. 1 and 2 and in a direction parallel to the surface of the bonded wafer 11 (left and right in FIGS. 1 and 2). When the adhesive tape 15 is peeled from the surface of the bonded wafer 11, it also functions as a peeling angle adjusting means for adjusting the angle at which the adhesive tape 15 is peeled off. The swing roller can be moved using a known moving mechanism such as a motor (not shown).

  The adhesive tape 15 stretched between the tape supply roller 12 and the tape collection roller 13 has a width larger than the diameter of the bonded wafer 11. And as the adhesive tape 15, the known tape which has the adhesive force which can peel and remove the part in which a poor bonding part exists from a bonded wafer, for example, a tape base material is a polyethylene-type base material, Is an acrylic pressure-sensitive adhesive, and a pressure-sensitive adhesive tape having an adhesive strength of 2 to 14 N / mm can be used.

  The wafer holding stage 16 vacuum-sucks and holds the back surface of the bonded wafer 11 at least during the inspection, and holds the bonded wafer 11 by suction. The bonding surface side of the adhesive tape 15 (the lower side in FIGS. 1 and 2). Is arranged. The wafer holding stage 16 is provided with a rotation mechanism such as a motor (not shown). Therefore, in this bonded wafer inspection apparatus 10, the bonded wafer 11 can be rotated around the center position of the bonded wafer 11 in the state where the bonded wafer 11 is sucked and held on the wafer holding stage.

  The affixing roller 17 is opposite to the affixing surface of the adhesive tape 15 (upper side in FIGS. 1 and 2), and in FIG. 1 and FIG. It is pivotally supported so as to be movable in a direction parallel to the surface of the wafer 11 (left and right direction in FIGS. 1 and 2). The affixing roller 17 has a width larger than the diameter of the bonded wafer 11, and from the affixing start position indicated by the broken line in FIG. 2 (a), the affixing indicated by the solid line in FIG. 2 (a). The adhesive tape 15 is attached to the surface of the bonded wafer 11 by moving the adhesive tape 15 while pressing the adhesive tape 15 against the surface of the bonded wafer 11 to the attachment end position. Note that the pasting roller 17 can be moved using a known moving mechanism such as a motor (not shown). By the way, in the bonded wafer inspection apparatus of the present invention, as a tape bonding means, a plate-like body that is arranged so as to be vertically movable above the bonded wafer and can press the entire bonded wafer, or air pressure or rubber A stamp mechanism using an elastic material such as a material can also be used.

  In the bonded wafer inspection apparatus 10, the peeling rollers 18 </ b> A and 18 </ b> B and the load cell 18 </ b> C form a peeling unit 18, and the peeling roller is a lower peeling roller with the lower peeling roller 18 </ b> A and the adhesive tape 15 interposed therebetween. It is comprised with the upper side peeling roller 18B arrange | positioned above 18A.

  Here, the lower peeling roller 18 </ b> A is on the bonding surface side of the adhesive tape 15, and is substantially flush with the surface of the bonded wafer 11 and parallel to the surface of the bonded wafer 11 in FIGS. 1 and 2. It is pivotally supported so as to be movable in any direction (left and right in FIGS. 1 and 2). Further, the upper peeling roller 18B is in a direction parallel to the surface of the bonded wafer 11 on the opposite side (upper side in FIGS. 1 and 2) to the adhesive tape 15 attachment surface (left and right direction in FIGS. 1 and 2). ) Is supported so as to be movable. The peeling rollers 18A and 18B have a width larger than the diameter of the bonded wafer 11, and from the peeling start position indicated by a broken line in FIG. 2 (c), the peeling indicated by a solid line in FIG. 2 (d). By moving to the end position, the adhesive tape 15 attached to the surface of the bonded wafer 11 is peeled off. The peeling rollers 18A and 18B can be moved using a known moving mechanism such as a motor (not shown). Incidentally, in the bonded wafer inspection apparatus of the present invention, only the lower peeling roller 18A may be used as the tape peeling means without providing the upper peeling roller 18B.

  The load cell 18C is disposed integrally with the lower peeling roller 18A, and measures the reaction force (the force acting in the left direction in FIGS. 1 and 2) that the lower peeling roller 18A receives from the adhesive tape 15 when the adhesive tape 15 is peeled off. Then, the peeling force of the adhesive tape 15 is calculated.

  The holding jig 19 is disposed on the opposite side of the adhesive tape 15 from which the adhesive tape 15 is attached, and is opposed to the wafer holding stage 16 and the bonded wafer 11 with the adhesive tape 15 in between. It has a crank shape in which the pressing portion 19A is formed. The pressing portion 19A is located above the outer peripheral portion of the bonded wafer 11 in FIGS.

  The holding jig 19 moves from a retracted position indicated by a broken line in FIG. 2B to a pressing position indicated by a solid line in FIG. 2B, and then the bonded wafer 11 via an adhesive tape 15. The adhesive tape 15 is securely attached to the outer peripheral part of the surface of the bonded wafer 11 by rotating while pressing the outer peripheral part with the pressing part 19 </ b> A. The holding jig 19 can be moved and rotated using a known moving / rotating mechanism such as a motor (not shown).

  Here, in general, a poorly bonded portion is likely to occur on the bonding end side (that is, the outer peripheral side) of the bonded wafer. Therefore, the range of the outer peripheral portion of the bonded wafer 11 pressed by the holding jig 19 is at least the wafer. It is preferable to set the range of the portion from the outermost periphery to 5 mm toward the wafer center.

  Further, the pressing portion may be a cylindrical member having a rectangular cross section as shown in FIGS. 1 and 2, but the adhesive tape is securely attached to the outer peripheral edge of the active layer 11 </ b> B of the bonded wafer 11, and From the viewpoint of removing dust and the like present on the terrace portion 11C by adhering to the adhesive tape 15, a stepped cylindrical member 19A ′ having a different diameter as shown in FIG. 3 is preferable.

  By the way, in the bonded wafer inspection apparatus of the present invention, if it is possible to press at least the outer peripheral portion of the bonded wafer having the adhesive tape bonded to the surface, it can be moved up and down above the bonded wafer as a pressing means. It is also possible to use a plate-like body which is disposed and can press the entire bonded wafer, or a stamp mechanism using an elastic material such as air pressure or rubber material.

  The image processing apparatus is an apparatus that detects whether there is a part where the surface of the bonded wafer 11 (active layer 11B) is peeled off using a camera or the like, for example. As the image processing device, specifically, a device that determines the presence or absence of a peeled portion by image analysis of data captured and stored by a camera can be used.

  And in the bonded wafer inspection apparatus 10 which has the structure mentioned above, the presence or absence of a bonding defect part is test | inspected as follows.

  First, after adhering and holding the bonded wafer 11 on the wafer holding stage 16 (wafer holding process), as shown in FIG. 2A, the adhering roller 17 is moved from the adhering start position indicated by the broken line to the solid line. It moves to the attachment end position shown (to the right in FIG. 2A) at a constant speed, and attaches the adhesive tape 15 to the surface of the bonded wafer 11 while pressing it (tape attaching step). At this time, the tape supply roller 12 supplies the adhesive tape 15 at an appropriate speed in accordance with the movement of the attaching roller 17 (tape supply process), and the swing roller 14A maintains the tension of the adhesive tape 15 constant. It moves in the direction (left direction in FIG. 2A) and adjusts the tension of the adhesive tape 15. In this tape attaching step, since the holding jig 19 is in the upper retracted position, the holding jig 19 and the applying roller 17 do not interfere with each other.

  Next, as shown in FIG. 2B, the pressing jig 19 is moved from the retracted position indicated by the broken line to the pressing position indicated by the solid line (downward in FIG. 2B). Thereafter, the holding jig 19 is rotated, and the outer peripheral portion of the bonded wafer 11 is pressed by the pressing portion 19A via the adhesive tape 15 (pressing step). At this time, since the adhering roller 17 and the swing roller 14E are located on substantially the same plane as the surface of the bonded wafer 11, the adhesive tape 15 is not naturally peeled off.

  After that, as shown in FIG. 2C, the holding jig 19 is moved from the pressing position indicated by the broken line to the retracted position indicated by the solid line (in the upward direction in FIG. 2C). After moving the holding jig 19, the swing roller 14E, the peeling rollers 18A and 18B, and the load cell 18C are peeled from the peeling start position indicated by the broken line in FIG. 2C to the end of peeling indicated by the solid line in FIG. The tape is moved to a position (to the right in FIGS. 2C and 2D) at a constant speed, and the adhesive tape 15 attached to the surface of the bonded wafer 11 is peeled off (tape peeling step). At this time, the tape collecting roller 13 collects the adhesive tape 15 peeled off in accordance with the movement of the peeling rollers 18A and 18B at an appropriate speed (tape collecting process), and the swing roller 14C increases the tension of the adhesive tape 15. It moves in the direction to keep it constant (left direction in FIG. 2C), and adjusts the tension of the adhesive tape 15. Further, the load cell 18C measures the reaction force and calculates the peeling force. In this tape peeling process, since the holding jig 19 moves to the upper retracted position, the holding jig 19 and the peeling rollers 18A, 18B and the like do not interfere with each other. Further, since the swing roller 14E is moved at a constant speed in a direction parallel to the surface of the bonded wafer 11 together with the peeling rollers 18A and 18B, the peeling rollers 18A and 18B are moved upward in FIG. Unlike the case where the adhesive tape 15 is peeled off, the adhesive tape 15 can be peeled at a constant angle (peeling angle) and a length from the peeling point to the peeling rollers 18A and 18B (peeling length). Therefore, it is possible to suppress variation in the peeling force.

  Then, the surface state of the bonded wafer 11 after peeling the adhesive tape 15 is observed with an image processing apparatus (not shown), and whether or not there is a part where the active layer 11B is peeled off, that is, there is a poorly bonded part. Inspect whether or not (surface inspection process). Note that the presence or absence of a poorly bonded portion may be determined by observing the adhesive tape 15.

  Thereafter, optionally, as shown in FIG. 2D, the wafer holding stage 16 is rotated by, for example, 90 ° (rotation process), and the attaching roller 17 is returned to the attaching start position, and the swing roller 14E, After returning the peeling rollers 18A and 18B to the peeling start position together with the load cell 18C (not shown), the tape supply process, the tape attaching process, the pressing process, the tape peeling process, the tape collecting process and the surface inspection process are repeated. Then, as shown in FIG. 4A, the bonded wafer 11 is rotated and bonded a total of four times with respect to the same bonded wafer 11 so that the bonding direction and the peeling direction of the adhesive tape 15 are shifted by 90 °. Inspect for misalignment. In FIG. 4, the attachment surface when the adhesive tape 15 is attached to the bonded wafer 11 is indicated by an inclined line portion, and the mark of the attachment surface after the adhesive tape 15 is peeled is indicated by a broken line. Yes. Incidentally, in the bonded wafer inspection apparatus of the present invention, the angle at which the bonded wafer is rotated can be appropriately adjusted.

  Then, if the bonded wafer inspection apparatus 10 inspects the bonding failure portion as described above, the adhesive tape supplied using the tape supply roller 12 and the tape recovery roller 13 in the tape attaching process and the tape peeling process. 15 can be applied and peeled off with the adhesive tape at a constant tension, so that the peeling inspection can be automated to reduce the cost and time required for the peeling inspection. In addition, it is possible to suppress the occurrence of variations in inspection accuracy by performing a peeling inspection under stable inspection conditions. Furthermore, in the pressing step, the adhesive tape 15 is securely applied to the outer peripheral portion of the bonded wafer 11 using the pressing jig 19, so that a defective bonding portion can be detected with higher accuracy. Further, in the rotation process, the bonded wafer 11 is rotated using a rotating mechanism, and the adhesive tape is applied and peeled from various directions to the same wafer, so that the adhesive tape is applied only from the same direction. Compared with the case where attachment and peeling are performed, the detection accuracy of a bonding failure portion can be further increased. Furthermore, since the peeling force is measured by the load cell 18C, the peeling force applied to the surface of the bonded wafer can be confirmed, and the optimization of the peeling conditions and the suppression of the occurrence of variations in detection accuracy are aimed at. be able to. Specifically, based on the peel force measured by the load cell 18C, the adhesive tape 15 can be peeled with a constant peel force, or under optimum peel conditions according to the wafer surface and the thickness of the active layer. The moving speed of the peeling rollers 18A and 18B can be controlled so that the adhesive tape 15 can be peeled off. Incidentally, in this bonded wafer inspection apparatus 10, by rotating the bonded wafer 11 using a rotating mechanism, an adhesive tape is applied only to the region on the bonding end side where a defective bonding portion is likely to occur and bonded. It is also possible to inspect only the end area. Therefore, in this bonded wafer inspection apparatus 10, only the region on the bonding end side where defective bonding portions are likely to occur can be inspected to reduce the inspection time and the amount of adhesive tape used.

  In the above example, the adhesive tape is applied to the entire surface of the bonded wafer. However, as shown in FIG. 4B, the adhesive tape is not applied to the entire surface of the bonded wafer 11, for example, a wafer. You may affix on only the surface of a half part, and you may test | inspect, making the affixing direction and peeling direction of the adhesive tape 15 differ. If it does in this way, compared with the case where an adhesive tape is affixed with respect to the whole surface of a bonded wafer, the usage-amount of an adhesive tape can be reduced. Further, if the adhesive tape 15 fed out little by little (advanced minutely) while rotating the bonded wafer 11 with the rotation mechanism is attached only to the outer peripheral portion of the bonded wafer 11 using the holding jig 19, the adhesive tape It is possible to inspect only the outer peripheral portion where bonding failure is likely to occur, while reducing the amount of use.

  Next, a second embodiment of the bonded wafer inspection apparatus of the present invention is shown in FIGS. In the bonded wafer inspection apparatus 30 of the second embodiment, the swing rollers 14C and 14E do not move when the adhesive tape 15 is peeled, and the peeling unit 18 sandwiches the bonded wafer 11 in the width direction of the inspection apparatus. It is arranged on the side opposite to the sticking roller 17 (right side in FIGS. 5 and 6), the peeling start position is a position indicated by a broken line in FIG. 6 (c), and the peeling end position is shown in FIG. 6 (d). The configuration is different from the bonded wafer inspection apparatus 10 of the first embodiment in that the position shown by the solid line and the load cell 18C, the separator 20, the swing roller 14F, and the separator collection roller 21 are not used. In this respect, it has the same configuration as the bonded wafer inspection apparatus 10. 5 and 6, the same reference numerals are used for the same members as those in the first embodiment.

  And in the bonded wafer inspection apparatus 30 which has the structure mentioned above, the presence or absence of a bonding defect part is test | inspected as follows.

  First, after adhering and holding the bonded wafer 11 on the wafer holding stage 16 (wafer holding step), as shown in FIG. 6A, the adhering roller 17 is moved from the adhering start position indicated by the broken line to the solid line. The tape is moved at a constant speed to the affixing end position shown (to the right in FIG. 6A) and affixed to the surface of the bonded wafer 11 while pressing the adhesive tape 15 (tape affixing step). At this time, the tape supply roller 12 supplies the adhesive tape 15 at an appropriate speed in accordance with the movement of the attaching roller 17 (tape supply process), and the swing roller 14A maintains the tension of the adhesive tape 15 constant. Moving in the direction (leftward in FIG. 6A), the tension of the adhesive tape 15 is adjusted. In this tape attaching step, since the holding jig 19 is in the upper retracted position, the holding jig 19 and the applying roller 17 do not interfere with each other.

  Next, as shown in FIG. 6B, the pressing jig 19 is moved from the retracted position indicated by the broken line to the pressing position indicated by the solid line (downward in FIG. 6B). Thereafter, the holding jig 19 is rotated, and the outer peripheral portion of the bonded wafer 11 is pressed by the pressing portion 19A via the adhesive tape 15 (pressing step). At this time, since the adhering roller 17 and the swing roller 14E are located on substantially the same plane as the surface of the bonded wafer 11, the adhesive tape 15 is not naturally peeled off.

  After that, as shown in FIG. 6C, the holding jig 19 is moved from the pressing position indicated by the broken line to the retracted position indicated by the solid line (in the upward direction in FIG. 6C). Then, after the holding jig 19 is moved, the sticking roller 17 is moved from the sticking end position indicated by the broken line in FIG. 6C to the sticking start position indicated by the solid line in FIG. c) and (d) to the left)), and the separation rollers 18A and 18B are moved from the separation start position indicated by the broken line in FIG. 6C to the end of separation indicated by the solid line in FIG. 6D. The tape is moved to a position (to the left in FIGS. 6C and 6D) at a constant speed, and the adhesive tape 15 attached to the surface of the bonded wafer 11 is peeled off (tape peeling step). At this time, the tape supply roller 12 rewinds the peeled adhesive tape 15 in accordance with the movement of the peeling rollers 18A and 18B at an appropriate speed, and the swing roller 14A keeps the tension of the adhesive tape 15 constant. It moves to the right (in FIG. 6C) and adjusts the tension of the adhesive tape 15. In this tape attaching process, since the pressing jig 19 moves to the upper retracted position, the pressing jig 19 does not interfere with the peeling rollers 18A and 18B. Further, since the affixing roller 17 is moved at a constant speed in the direction parallel to the surface of the bonded wafer 11 together with the peeling rollers 18A and 18B, the affixing roller 17 and the peeling rollers 18A and 18B are shown in FIG. Unlike the case where the adhesive tape 15 is peeled off by moving upward, the adhesive tape 15 is peeled at a constant angle (peeling angle) and the length from the peeling point to the peeling rollers 18A and 18B (peeling length). Can do. Therefore, it is possible to suppress variation in the peeling force.

  Then, the peeled adhesive tape 15 is collected by the tape collecting roller 13 (tape collecting step), and the surface state of the bonded wafer 11 after peeling the adhesive tape 15 is observed with an image processing apparatus (not shown), and the active layer 11B. It is inspected whether or not there is a peeled portion, that is, whether or not there is a poorly bonded portion (surface inspection step).

  Thereafter, optionally, as shown in FIG. 6D, the wafer holding stage 16 is rotated by, for example, 90 ° (rotation process), and the separation rollers 18A and 18B are returned to the separation start position (not shown). The tape supplying process, the tape attaching process, the pressing process, the tape peeling process, the tape collecting process and the surface inspection process are repeated. Then, as shown in FIG. 4 (a), the presence / absence of a defective bonding portion is inspected a total of four times by changing the bonding direction and the peeling direction of the adhesive tape 15 by 90 ° with respect to the same bonded wafer 11. .

  If the bonded wafer inspection apparatus 30 inspects the defective bonding portion as described above, the same effect as that obtained when the bonded wafer inspection apparatus 10 inspects the defective bonding portion can be obtained. .

  The bonded wafer inspection apparatus of the present invention has been described above using the first embodiment and the second embodiment. However, the bonded wafer inspection apparatus of the present invention is not limited to the above embodiment. The bonded wafer inspection apparatus of the present invention can be modified as appropriate.

  EXAMPLES Hereinafter, although an Example demonstrates this invention further in detail, this invention is not limited to the following Example at all.

Example 1
For seven bonded wafers manufactured from the same lot and having a diameter of 200 mm, an active layer thickness of 20 μm, and an oxide film layer (box layer) of 5 μm, a fully automated peeling inspection using the bonded wafer inspection apparatus 10 shown in FIG. Went. In carrying out the inspection, the rotation process was not performed, and the adhesive tape was attached and peeled twice in the same direction.
And when the average value of the number of the defective bonding parts detected was calculated, it was 0.4 per bonded wafer.

(Example 2)
For seven bonded wafers produced in the same manner as in Example 1, peeling inspection was performed fully automatically using the bonded wafer inspection apparatus 10 shown in FIG. In carrying out the inspection, a rotation process was performed, and the adhesive tape was applied and peeled off by varying the adhesive tape attaching direction and the peeling direction by 90 ° as shown in FIG. I went twice.
And when the average value of the number of the defective bonding parts detected was calculated, it was 1.1 per bonded wafer.

  From Examples 1 and 2, if the bonded wafer is rotated using a rotation mechanism, and the adhesive tape is attached and peeled from various directions to the same wafer, the detection accuracy of the defective bonding portion is further improved. I know you get.

  According to the bonded wafer inspection apparatus of the present invention, the peeling inspection can be automated to reduce the cost and time required for the peeling inspection.

DESCRIPTION OF SYMBOLS 10 Bonded wafer inspection apparatus 11 Bonded wafer 11A Support wafer 11B Active layer 11C Terrace part 12 Tape supply roller 13 Tape collection | recovery roller 14A, 14B, 14C, 14D, 14E, 14F Swing roller 15 Adhesive tape 16 Wafer holding stage 17 Pasting Roller 18 Peeling unit 18A Lower peeling roller 18B Upper peeling roller 18C Load cell 19 Holding jig 19A, 19A 'Pressing part 20 Separator 21 Separator recovery roller 30 Bonded wafer inspection device

Claims (5)

A bonded wafer inspection device that inspects the presence or absence of a bonding failure by peeling off the pressure-sensitive adhesive tape from the surface of the bonded wafer after applying the pressure-sensitive adhesive tape to the surface of the bonded wafer,
A tape supply means for supplying an adhesive tape to be bonded to the surface of the bonded wafer;
A tape collecting means for collecting the adhesive tape peeled off from the surface of the bonded wafer;
Wafer holding means for holding the bonded wafer on the side of the adhesive tape attached between the tape supply means and the tape recovery means; and
It is arranged so as to be able to reciprocate between a sticking start position and a sticking end position, and moves from the sticking start position to the sticking end position while pressing the adhesive tape against the surface of the bonded wafer. A tape attaching means for attaching an adhesive tape to the surface of the bonded wafer; and
A tape that is disposed so as to be able to reciprocate between a peeling start position and a peeling end position, moves from the peeling start position to the peeling end position, and peels off the adhesive tape attached to the surface of the bonded wafer. Peeling means;
Tension adjusting means for adjusting the tension of the adhesive tape;
An inspection apparatus for bonded wafers, comprising:   A pressing unit that is disposed to face the wafer holding unit with the adhesive tape interposed therebetween, and that presses at least the outer peripheral portion of the bonded wafer via the adhesive tape that is bonded to the surface of the bonded wafer; The bonded wafer inspection apparatus according to claim 1, wherein the bonded wafer inspection apparatus is characterized.   3. The bonded wafer inspection apparatus according to claim 1, wherein the wafer holding unit includes a rotation mechanism that rotates the bonded wafer around the center position of the bonded wafer to be held. .   The bonded wafer inspection apparatus according to claim 1, wherein the tape peeling unit includes a reaction force measuring mechanism that measures a reaction force of the adhesive tape.   5. The bonded wafer inspection apparatus according to claim 1, further comprising surface inspection means for observing the surface of the bonded wafer after the adhesive tape is peeled off.

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