JP5373707B2 - Position shift detection device for bonded substrates, semiconductor manufacturing apparatus using the same, and method for detecting position shift of bonded substrates - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To collectively determine a shift amount of a substrate center position, for a laminated substrate composed of two sets of vertically layered discoidal substrates, in element forming or the like. <P>SOLUTION: Contour measurement means 3A detects a contour shape of two sets of superposed substrates 21, 22 from a projection image of a laminated substrate 2 in a thickness direction, while edge shape measurement means 4 detects respective edge shapes of the two sets of substrates 21, 22 from a projection image of the laminated substrate 2 in a tangential direction, at multiple points in a circumferential direction. Then, calculation means 6 detects shape data of either one of the substrate sets from a detection result of the contour measurement means 3 to determine a diameter and a center position, while as for the other substrate set, shape data is obtained from a relative positional relationship between the two sets of substrates detected by the edge shape measurement means 4, using the shape data of the other set of substrate as a standard, to determine a diameter and a center position. Thereafter, the shift amount is determined from a distance of the center position between the two sets of substrates. <P>COPYRIGHT: (C)2012,JPO&amp;INPIT

Description

  The present invention relates to an apparatus and method for detecting the amount of misalignment of a bonded substrate in which two sets of disk-shaped substrates realized as semiconductor wafers are bonded to each other, and the same. The present invention relates to a semiconductor manufacturing apparatus.

  In recent years, in semiconductors, a plurality of semiconductor elements are stacked in order to realize a plurality of functions, or a support substrate is stacked as the thickness is reduced. Specifically, in the manufacturing process of a semiconductor device called SOI (Silicon on Insulator), TSV (Through-Silicon Via / Si through electrode), BSI (Back Side Illumination / Back-illuminated imaging device), etc., the semiconductor Wafers are being stacked.

  By the way, in such a bonded substrate, it is impossible to form a through electrode or an element unless it is accurately detected how the two sets of substrates are bonded. Therefore, in Patent Document 1, notches formed on the outer periphery of the semiconductor wafer are detected, and the rotation angles of the two sets of substrates are detected. Patent Document 2 has been proposed as a technique for measuring the diameter of a semiconductor wafer.

  In the present specification, for convenience, the stacking direction of the two sets of substrates is set up and down. However, the stacking direction of the two sets of substrates may be set to the left and right with reference to the state of standing the two sets of substrates. It suffices if they are laminated in the thickness direction. In addition, one or both of the two sets of substrates may be multilayer substrates, and therefore, two sets are used instead of two.

JP 2009-32802 JP 7-218228 A

  In the prior art of Patent Document 1, the rotation angles of two sets of substrates are detected, but how much the center is misaligned cannot be detected, and two sets of substrates are detected individually. It is.

  On the other hand, although the prior art of Patent Document 2 seeks the diameter and the center position, it targets a single substrate and cannot detect the deviation of the diameter and the center position in the bonded substrate. That is, since the shape of a single wafer that is not bonded is almost a circle, according to this Patent Document 2, it is possible to measure the fitting diameter, average diameter, and center of the entire circumference. However, when two sets of wafers are bonded together, in Patent Document 2, it is not possible to perform measurement by separating the two sets of wafers.

  FIG. 7 is a graph showing measurement results of the bonded substrate board by the present inventors. The object to be measured is a wafer having a diameter of 300 mm. In FIG. 7A, the horizontal axis indicates the rotation angle position based on the notch, and the vertical axis indicates the measurement result of the radius at each rotation angle position. The measurement result of FIG. 7A is shown in a pie chart as shown in FIG. 7B. From FIG. 7B, it is understood that the two disc-shaped wafers are bonded with their centers shifted. The state of FIG. 7B is schematically shown in FIG. 8A. The state of FIG. 8A can be inferred from the fact that the two circles are shifted and overlapped in the graph of FIG. 7B, but as shown in FIG. 8B, there is a difference between the diameters of the two wafers. In the situation where one is included in the other, the prior art of Patent Document 2 can measure only the outline of a wafer having a large diameter.

  An object of the present invention is to provide a bonded substrate position shift detection device capable of collectively detecting the amount of shift between bonded substrates, a semiconductor manufacturing apparatus using the same, and a bonded substrate position shift detection method. Is to provide.

A positional deviation detection device for a bonded substrate of the present invention is a device for detecting the amount of deviation between the two sets of substrates in a bonded substrate formed by laminating two pairs of disk-shaped substrates up and down, The outermost edge measuring means for detecting the contour shape as a whole of the two sets of substrates, and the relative unevenness in the radial direction of the outer peripheral edge of the bonded substrate at a plurality of points in the circumferential direction are measured. , a tip position measuring means for measuring the relative tip position relationship of the outer peripheral edge between the two sets of substrates, said from the detection result of the outermost edge measuring unit, detecting a contour shape data of one of the pair of substrates and, for the other set of substrate, based on the contour data of the one set of the substrate, the contour shape data from the relative tip position relationship between two sets of substrates measured at the tip position measuring means the calculated contour shape data between the two sets of substrates Comparing the data, characterized in that it comprises a calculating means for calculating a shift amount between the two sets of substrates.

For example, the computing means, said from the detection result of the outermost edge measuring means detects the contour shape data of one of the pair of substrates, a first arithmetic means for determining the diameter and center position, before Symbol first A third calculation means for comparing the relative tip position relationship measured by the tip position measurement means with respect to the calculation result of the calculation means, and obtaining contour shape data of the other set of substrates; From the calculation result of the third calculation means, fourth calculation means for obtaining the diameter and center position of the other set of substrates, and the calculation result of the fourth calculation means for the calculation result of the first calculation means And a fifth operation means for detecting the amount of deviation of the center position between the two sets of substrates by comparing the calculation results of the means.

Also, the method for detecting a positional deviation of a bonded substrate of the present invention is a method for detecting the amount of deviation between the two sets of substrates in a bonded substrate formed by laminating two disc-shaped substrates. The outermost edge measurement step for detecting the contour shape as a whole of the two sets of substrates, and the relative unevenness in the radial direction of the outer peripheral edge of the bonded substrate at a plurality of points in the circumferential direction. From the detection result in the tip position measurement step of measuring and measuring the relative tip position relationship of the outer peripheral edge between the two sets of substrates and the detection result in the outermost edge portion measurement step, the contour shape of one of the sets of substrates It detects data for the other set of substrate, based on the contour data of the one set of the substrate, from the relative tip position relationship between two sets of substrates measured at the tip position measuring step obtains contour shape data, the By comparing the contour data among the set of substrates, characterized in that it comprises a calculation step of obtaining a shift amount between the two sets of substrates.

For example, the computing step, the the detection result of the outermost edges measuring step, detects the contour shape data of one of the pair of substrates, a first calculation step of obtaining a diameter and center position, before Symbol first A third calculation step for comparing the relative tip position measured in the tip position measurement step with the calculation result in one calculation step and obtaining contour shape data of the other set of substrates. From the calculation result in the third calculation step, the fourth calculation step for obtaining the diameter and center position of the other set of substrates, and the calculation result in the first calculation step, A fifth calculation step of comparing a calculation result in the fourth calculation step and detecting a shift amount of a center position between the two sets of substrates.

  According to the above configuration, in a bonded substrate formed by stacking two disk-shaped substrates on top and bottom, for forming an element on each or one of the substrates, for example, between the substrates In detecting the amount of deviation, the following method is used. That is, first, the outermost edge measuring means detects the overall contour shape of the two sets of substrates, while the tip position measuring means projects the tangential projection of the bonded substrates at a plurality of points in the circumferential direction. From the image or the like, the tip position of each of the two sets of substrates is measured. Then, the computing means detects the contour position data of one set of substrates from the detection result of the outermost edge measuring means, and obtains the diameter and the center position, while the other set of substrates is one of them. The contour position data is obtained from the relative tip position relationship between the two sets of substrates detected by the tip position measuring means on the basis of the contour position data of the set of substrates, and the diameter and the center position are obtained. Thereafter, the amount of deviation is obtained from the distance of the center position between the two sets of substrates.

  Therefore, the diameters of the two bonded substrates and the amount of positional deviation between them can be determined together.

  Furthermore, in the positional deviation detection device for a bonded substrate board according to the present invention, the tip position measuring means includes a rotating means for mounting and rotating the bonded substrate board, and a vicinity of the outer peripheral edge of the bonded substrate board. On the other hand, light is irradiated in the tangential direction of the bonded substrate, and with the rotation of the rotating means, a projected image of each point in the circumferential direction is taken to detect relative unevenness between the two sets of substrates. And a first optical system.

  According to said structure, by rotating the bonding board | substrate relatively by a rotation means, it is 2 sets in the several points of the said circumferential direction from the projection image by the illumination light irradiated from the tangential direction by the 1st optical system. The edge shape of each of the substrates can be easily detected.

  Moreover, in the positional deviation detection apparatus for a bonded substrate board according to the present invention, the first optical system includes a point light source, a collimator lens that creates parallel light by entering light from the point light source, and the outer peripheral edge portion. It is characterized by comprising a condensing optical system for condensing light that has passed through the vicinity, and an image sensor on which a shadow image by the light that has passed through the condensing optical system is projected.

  According to said structure, the light of a point light source is irradiated toward an image sensor over the outer periphery part of the said bonding board | substrate, and the edge image of the said 2 sets of board | substrates is projected on an image sensor by projecting It is possible to detect a change in relative unevenness. Further, by using a point light source, a collimator lens, preferably a telecentric lens, even if the two sets of substrates have a long depth, that is, a large diameter, there is little blurring of the edge in the image sensor, and in the vicinity of the edge. There are few generated diffraction fringes, and a good edge image can be obtained.

Furthermore, in the positional deviation detection device for a bonded substrate board according to the present invention, the tip position measuring means includes a rotating means for mounting and rotating the bonded substrate board, and a vicinity of the outer peripheral edge of the bonded substrate board. On the other hand, along with the rotation of the rotating means, slit light is irradiated in the radial direction of the bonded substrate, and the bright line image is picked up from one or more directions, and relative unevenness between the two sets of substrates is detected. And first light cutting means.

  According to said structure, by rotating the bonding board | substrate relatively by a rotation means, from the picked-up image from one or more directions of the slit light irradiated with the bright line by radial direction by the light cutting means, the said circumferential direction plurality The edge shape of each of the two sets of substrates at a point can be easily detected.

Moreover, in the position shift detection apparatus of the bonding board | substrate of this invention, the said outermost edge part measurement means carries the said bonding board | substrate, the rotation means to rotate relatively, and the outer periphery part vicinity of the said bonding board | substrate. On the other hand , the light is irradiated in the thickness direction of the bonded substrate , the light irradiated near the outer peripheral edge is received from the opposite direction as the rotating means rotates, and the outline of the bonded substrate as a whole is received. And a second optical system for detecting the shape .

  According to said structure, by rotating a bonding board | substrate relatively by a rotation means, the 2nd optical system detects the micro unevenness | corrugation of the outline of the said bonding board | substrate from the change of the width | variety of slit light. be able to. The outer diameter (contour) can be obtained by adding the distance from the center of the rotating means to the reference position of the slit light to the change in the width of the slit light from the reference position.

Furthermore, in the positional deviation detection apparatus for bonded substrates of the present invention, the outermost edge measuring means includes a rotating means for mounting and rotating the bonded substrate, and the vicinity of the outer peripheral edge of the bonded substrate. On the other hand, light is irradiated in the tangential direction of the bonded substrate, and the projected image of each point in the circumferential direction is taken along with the rotation of the rotating means, and the overall contour shape of the bonded substrate is detected. And a first optical system.
Moreover, in the position shift detection apparatus of the bonding board | substrate of this invention, the said outermost edge part measurement means carries the said bonding board | substrate, the rotation means to rotate relatively, and the outer periphery part vicinity of the said bonding board | substrate. On the other hand, along with the rotation of the rotating means, slit light is irradiated in the radial direction of the bonded substrate to illuminate the bright line image from one or more directions, and the position on the more distal side of the two sets of substrates And a second light cutting means for making the overall contour shape of the bonded substrate.

  Further, the semiconductor manufacturing apparatus of the present invention is characterized in that the position shift detection device is used and the element formation position on the bonded substrate is corrected in response to the position shift detection result.

  According to the above configuration, when forming an element on one or both of the bonded upper and lower substrates, a semiconductor manufacturing capable of forming an element at an accurate position in consideration of a deviation of the bonding position. An apparatus can be realized.

  As described above, the apparatus and method for detecting a positional deviation of a bonded substrate of the present invention includes the above two sets for detecting the amount of deviation between the bonded substrates formed by stacking two disk-shaped substrates in the vertical direction. The contour shape as a whole of the two substrates is detected, and the diameter and the center position are obtained from the contour shape data of one of the substrates, while the tip positions of the two substrates are determined at a plurality of circumferential points. Detecting the other set of substrates, the contour position data is obtained from the relative positional relationship between the two sets of substrates based on the contour position data of the one set of substrates, and the diameter and the center position are further determined. The deviation amount is obtained from the distance of the center position between the two sets of substrates.

  Therefore, the diameters of the two sets of bonded substrates and the amount of positional deviation between them can be determined together.

  Further, as described above, the semiconductor manufacturing apparatus according to the present invention uses the above-described position shift detection device when performing element formation on each of the bonded upper and lower substrates, or one of them, and responds to the position shift detection result. Then, the element formation position on the bonded substrate is corrected.

  Therefore, the element can be formed at an accurate position in consideration of the shift of the bonding position.

It is a figure which shows typically the whole structure of the position shift detection apparatus which concerns on one Embodiment of this invention. It is a figure for demonstrating the measurement principle of the outline shape of the bonding board | substrate by the outermost edge part measurement means in the said position shift detection apparatus. It is a figure for demonstrating the measurement principle of the edge shape of the bonding board | substrate by the front-end | tip position part measurement means in the said position shift detection apparatus. It is a figure which shows an example of the image extracted with the edge shape image sensor, and the result of having extracted the outline shape from the captured image by the image processing means. It is a figure which shows the aspect of bonding of 2 sets of board | substrates in the bonding board | substrate from which the captured image of FIG. 4 is obtained. It is a flowchart for demonstrating the processing operation of the said position shift detection apparatus. It is a graph which shows the example of a measurement of the outline shape of a bonding board | substrate. It is a figure which shows the example of bonding of the said bonding substrate typically.

  FIG. 1 is a diagram schematically showing an overall configuration of a positional deviation detection apparatus 1 according to an embodiment of the present invention. This positional deviation detection apparatus 1 detects the deviation of the diameter and the center position of two sets of substrates 21 and 22 in a bonded substrate 2 formed by laminating two sets of disc-shaped substrates 21 and 22 above and below. It is a device to do. The substrates 21 and 22 are both made of a semiconductor wafer formed with elements before or after forming elements. This positional deviation detection apparatus 1 includes an outline measuring means 3 that is an outermost edge measuring means, an edge shape measuring means 4 that is a tip position measuring means 4, an image processing means 5, a computing means 6, and an output means 7. And control means 8.

  The contour measuring means 3 detects a contour shape obtained by combining the two sets of substrates 21 and 22 from the projection image in the thickness direction of the bonded substrate 2. For this reason, the contour measuring means 3 is mounted on the bonded substrate 2 and is positioned near the rotating turntable 31 and the outer peripheral edge of the bonded substrate 2, and is constant in the radial direction of the bonded substrate 2. An optical system 32 for detecting the outer shape of the bonded substrate 2 from a change in the width of the received light beam accompanying the rotation of the turntable 31. It is configured with. The optical system 32 is realized by a diameter sensor composed of a laser scanner.

  FIG. 2 is a view for explaining the principle of measuring the contour shape of the bonded substrate 2 by the contour measuring means 3. The optical system 32 includes a slit light source 321 that generates slit light 322 extending in the radial direction X of the bonded substrate 2, and a line sensor 323 that receives light that has passed near the edge of the bonded substrate 2 of the slit light 322. The slit light source 321 and the line sensor 323 are opposed to each other, and are provided with a generally U-shaped holding member 324 that is held near the edge of the bonded substrate 2. The slit light source 321 is a laser light source, and generates slit light that is parallel to each other and extends in the radial direction X of the bonded substrate 2 as described above, as the slit light 322.

  Therefore, by rotating the bonded substrate 2 with the turntable 31, the optical system 32 provided at the fixed position can detect minute irregularities in the contour of the bonded substrate 2 from the change in the width of the slit light. it can. Specifically, the control unit 8 rotates the turntable 31, and the calculation unit 6 changes the width of the slit light from the reference position (sensor reference position) P1 (the distance of the shadow portion) as shown in the following equation. ) By adding the distance L from the center P0 of the turntable 31 to the reference position P1, the outer diameter (contour) R can be obtained.

R = S + L
The contour position data of the bonded substrate 2 measured in this way is as shown in FIG. 7 (a) to FIG. 7 (b) described above, and by performing circle fitting in the calculation means 6 based on this data, The fitting diameter, average diameter, and center position can be calculated. In that case, out of the two sets of substrates 21 and 22, the shape data of one set of substrates is extracted. However, since the measurement ratio is better when the proportion of the entire contour data is larger, the larger one is usually selected. select. However, if there is no inclusion relationship as shown in FIG. 8B, calculation is possible even if the smaller one is selected.

  On the other hand, the edge shape measuring means 4 is mounted on the bonded substrate 2 and is positioned near the rotating turntable 41 and the outer peripheral edge of the bonded substrate 2, and parallel to the tangential direction of the bonded substrate 2. The optical system 42 is configured to irradiate light and detect relative unevenness of the edges of the two sets of substrates 21 and 22 from an edge projection image accompanying the rotation of the turntable 41. Therefore, by rotating the bonded substrate 2 with the turntable 41, two sets of substrates 21 at a plurality of points in the circumferential direction θ are obtained from the projection image by the illumination light irradiated from the tangential direction by the optical system 42 provided at the fixed position. , 22 can be easily detected.

  The turntable 41 may be shared with the above-described turntable 31, and according to the installation position of the optical systems 32 and 42, the turntable 41 moves between them while the bonding substrate 2 is mounted. May be. The turntables 31 and 41 constitute rotating means. As the rotating means, the optical systems 32 and 42 are configured to support the optical systems 32 and 42 and rotate the outer periphery of the fixed laminated substrate 2. The structure which rotates the bonding board | substrate 2 relatively should just be used.

  FIG. 3 is a view for explaining the principle of measuring the edge shape of the bonded substrate 2 by the edge shape measuring means 4. The optical system 42 includes a point light source 421 that emits scattered light 420, a collimator lens 423 that creates parallel light 422 from the scattered light 420, and both sides or object sides that collect the parallel light 422 that has passed near the edge. A telecentric lens 424 having a telecentric structure and an image sensor 425 for receiving a projection image condensed by the telecentric lens 424 are configured. In FIG. 3, the image sensor 425 is further provided with a telecentric lens 426 and an aperture stop 427 for entering light with an image side telecentric structure. The point light source 421 includes a light emitting diode.

  With this configuration, the parallel light 422 is irradiated toward the image sensor 425 through the edge of the bonded substrate 2, and a shadow image of the edge is projected onto the image sensor 425. It is possible to detect a change in relative unevenness of the 21 and 22 edges. By using the point light source 421, the collimator lens 423, and the telecentric lens 424, even if the depth length of the two sets of substrates 21 and 22 is long, that is, the diameter is large, the edge blur in the image sensor 425 is small. Moreover, there are few diffraction fringes generated in the vicinity of the edge, and a good edge image can be obtained.

  In measuring the edge shape, the control means 8 determines the notch position from the contour shape of the bonded substrate 2 measured by the contour measuring means 3, and rotates the turntable 41 while rotating the angular position at the notch position. , The notch position is excluded (because the notch portion is notched so that the edge shape cannot be measured), and the image sensor 425 reads the shadow image at intervals in the circumferential direction θ. The control means 8 may turn on the point light source 421 continuously during the measurement of the edge shape, or may blink it in conjunction with the reading operation by the image sensor 425.

  When the notch position is 0 °, for example, when reading is every 45 °, seven points of 45 °, 90 °, 135 °, 180 °, 225 °, 270 °, and 315 ° become measurement points, or 22.5 ° , 67.5 °, 112.5 °, 157.5 °, 202.5 °, 247.5 °, 292.5 °, and 337.5 ° may be used as measurement points. The measurement points do not need to be equally spaced, and any number of measurement points may be used as long as the number is three or more. However, the measurement accuracy improves as the score increases.

  FIG. 4 shows an example of an image captured by the image sensor 425 and the result of extracting the contour shape from the captured image by the image processing means 5. In the example of FIG. 4, as schematically shown in FIG. 5, two sets of substrates 21 and 22 are perfect circles having the same diameter, and the diameter line direction of 135 ° (315 °) with respect to the notch position. The state which shifted is shown. Therefore, at the position of 45 ° (225 °), as shown in FIG. 4A, the edges of the two sets of substrates 21 and 22 are substantially equidistant from the center. In contrast, at the position of 135 °, the edge of the upper substrate 21 protrudes from the edge of the lower substrate 22 as shown in FIG. On the other hand, at the position of 315 °, the edge of the lower substrate 22 protrudes from the edge of the upper substrate 21 as shown in FIG.

  FIGS. 4D to 4F show the results of extracting the contour shape in the image processing means 5 from the captured images of FIGS. 4A to 4C, respectively. As shown in FIG. 4 (d), at the position of 45 ° (225 °) perpendicular to the direction of deviation (135 ° (315 °)) between the two pairs of substrates 21 and 22 having the same diameter and a perfect circle. The edge end surfaces A1 of the two sets of substrates 21 and 22 are aligned. At this time, if the radius measured by the contour measuring means 3 is R1, the radii of the substrates 21 and 22 are both R1.

  On the other hand, as shown in FIG. 4E, the edge of the upper substrate 21 protrudes by A2 from the edge of the lower substrate 22 at a position of 135 ° where the deviation is maximum. At this time, if the radius measured by the contour measuring means 3 is R2, the radius of the upper substrate 21 is R2, and the radius of the lower substrate 22 is R2-A2. Similarly, as shown in FIG. 4F, the edge of the lower substrate 22 protrudes by A3 from the edge of the upper substrate 21 at a position of 315 ° where the deviation is maximum. At this time, if the radius measured by the contour measuring means 3 is R3, the radius of the lower substrate 22 is R3 and the radius of the upper substrate 21 is R3-A3. When the diameters of the substrates 21 and 22 are equal to each other, A2 = A3. Based on the diameters of the substrates 21 and 22 at the plurality of locations thus obtained, the computing means 5 calculates the diameter and the center position of the substrates 21 and 22 and the shift amount of the center position as described later.

  The image processing means 5 extracts the contour shape of the substrates 21 and 22 from the captured image of the image sensor 425 as described above. However, the image processing means 5 exceeds the resolution of the image sensor 425 by subpixel units by image processing. It may be possible to detect the deviation. Alternatively, by combining the point light source 421, the collimator lens 423, and the telecentric lens 424, the edge blur in the image sensor 425 is small, and diffraction fringes generated in the vicinity of the edge are small, so that a good edge image can be obtained. In addition, when the image sensor 425 has a high resolution, the image processing means 5 may not be provided.

  FIG. 6 is a flowchart for explaining the processing operation of the positional deviation detection apparatus 1 configured as described above. Steps S11 to S13 mainly show the contour measuring operation, steps S21 to S23 mainly show the edge shape measuring operation, and steps S31 to S33 mainly show the operation of calculating the diameter and positional deviation amount of the other substrate.

  In step S <b> 11, the contour measuring means 3 measures contour position (radius) data over the entire circumference of the bonded substrate 2 by the optical system 32 while rotating the bonded substrate 2 with the turntable 31. In step S12, shape data of one substrate (A) is extracted from the measurement data by the calculation means 6. In step S13, the fitting diameter, average diameter, and center position of the substrate A are calculated from the shape data by performing circle fitting in the calculation means 6.

  On the other hand, in step S21, the edge shape measuring means 4 rotates the bonded substrate 2 with the turntable 41, and the optical system 42 takes edge images at a plurality of locations on the bonded substrate 2, and step S22. Then, the captured image is subjected to image processing by the image processing means 5, and the contour shapes of the edge portions of the two sets of substrates A and B are extracted. In step S23, the extracted contour shape is compared by the calculation means 6, and the difference in radius between the upper substrate 21 and the lower substrate 22 (A2, A3 in 4) is obtained. Any of the processes in steps S11 to S13 and the processes in steps S21 to S23 may be performed first.

  Subsequently, in step S31, with respect to one substrate A determined in step S12, the fitting diameter, average diameter, and center position determined in step S13 are placed on the other substrate B determined in step S23. The contour data of the other substrate B is obtained from the difference in radius. At this time, it is first determined whether one of the substrates A determined in step S12 is the upper substrate 21 or the lower substrate 22.

  As a determination method, when the diameter of the substrate A and the diameter of the substrate B are simply compared, the diameter of the substrate A is small, and the diameter of the upper substrate 21 and the diameter of the lower substrate 22 are compared. When the diameter of the lower substrate 22 is small, the substrate A is regarded as the lower substrate 22. For that purpose, when performing diameter calculation by circular fitting based on the contour measurement result in step S13, it is necessary to calculate not only one substrate A but also the diameter of the other substrate B. In addition, it is necessary to calculate in advance the diameter of the upper substrate 21 and the diameter of the lower substrate 22 by calculating the tip position of each point from the extraction result of the edge shape in step S22.

  On the other hand, as another method of determining which of the substrates A and B is the upper side or the lower side, there is a method of determining at the edge tip position at a specific position. Specifically, the determination is made based on which substrate is located outside at a certain point, for example, a notch position. In this case, the specific point may not be one point, and a plurality of points are better. For example, at the notch position, when the substrate A is outside the substrate B and the lower substrate 22 is outside the upper substrate 21, the substrate A is regarded as the lower substrate 22. is there.

  Thus, when the top and bottom of the substrates A and B are determined, the contour position of the other substrate B is calculated. As described above, the calculation is performed from the diameter of one substrate A obtained by the contour measurement in step S13 and the difference in radius obtained by the edge shape measurement in step S23. For example, in FIGS. 4D to 4F, the difference in radius is set to A1, A2, and A3, respectively (here, A1 = 0, A2> 0, A3 <0 on the basis of the lower substrate 22). If the radii of one substrate A are R1, R2, and R3, respectively, the radii of the other substrate B can be obtained from R1, R2 + A2, and R3-A3, respectively. The radius of the substrate B at angular positions other than 45 ° (225 °), 135 °, and 315 ° shown in FIG. 4 can be obtained in the same manner. In the example of FIG. The coordinates of 7 points are obtained. Here, the radii R1 to R3 of the substrate A can all be set to the same value, R1 = R2 = R3, based on the diameter of the circle fitting, or a local numerical value can be set as the radius based on the contour shape. You can also. However, when a local numerical value is used, an angle that cannot be measured because it is hidden by the substrate B needs to be an estimated value.

  Thereafter, in step S32, the diameter and center position of the substrate B are obtained by circular fitting the coordinates of the seven points of the substrate B obtained in step S31. In step S33, the center of the substrates A and B is obtained. By comparing the center coordinates, the amount of misalignment of the center can be obtained. The obtained diameter and center misalignment amount are displayed and output from the output means 7.

  The steps S12 and S13 constitute a first computing means and a first computing step, the step S23 constitutes a second computing means and a second computing step, and the step S31 comprises a third computing means and a first computing means. A third calculation step is constituted, the step S32 constitutes a fourth calculation means and a fourth calculation step, and the step S33 constitutes a fifth calculation means and a fifth calculation step.

  By comprising in this way, in the bonding board | substrate 2 formed by laminating | stacking two disk-shaped board | substrates 21 and 22 (A, B) up and down, each of those board | substrates 21, 22 (A, B) Alternatively, when performing element formation on one side, the deviation of the diameters and center positions of the substrates 21 and 22 (A and B) can be obtained collectively from the results of the contour measurement and the edge shape. Can do.

  Further, such a positional deviation detection apparatus 1 is used in a semiconductor manufacturing apparatus, and in response to the positional deviation detection result, the element formation position on the bonding substrate 2 is corrected, thereby taking into account the positional deviation of the bonding position. Thus, element formation can be performed at an accurate position.

  In the above-described example, the edge shape measuring means 4 including the turntable 41 and the optical system 42 is used as the tip position measuring means, but the turntable 41 and the outer peripheral edge of the bonded substrate 2 are used. With the rotation of the turntable 41, slit light is emitted in the radial direction of the bonded substrate 2 to capture the bright line image from one or more directions, and the two sets of substrates 21, Optical cutting means for detecting relative unevenness of the 22 edges may be used.

  In the above-described example, the contour measuring means 3 including the turntable 31 and the optical system 32 is used as the outermost edge measuring means. However, the turntable 31 and the bonded substrate 2 With the rotation of the turntable 31, the slit light is irradiated in the radial direction of the bonded substrate 2 and the bright line images are picked up from two different directions. The optical cutting means which makes the position of the more front end side of 21 and 22 into the said outline position of the said bonding board | substrate may be used.

DESCRIPTION OF SYMBOLS 1 Position shift detection apparatus 2 Bonding board | substrate 21 Upper side board | substrate 22 Lower side board | substrate 3 Contour measurement means 31 Rotating means 32 Optical system 321 Slit light source 322 Slit light 323 Line sensor 324 Holding member 4 Edge shape measuring means 41 Rotating means 42 Optical system 420 Scattered light 421 Point light source 422 Parallel light 423 Collimator lens 424 Telecentric lens 425 Image sensor 426 Telecentric lens 427 Aperture stop 5 Image processing means 6 Computing means 7 Output means 8 Control means

Claims (11)

In a bonded substrate formed by laminating two disc-shaped substrates on top and bottom, an apparatus for detecting the amount of deviation between the two substrates.
An outermost edge measuring means for detecting a contour shape as a whole combining the two sets of substrates;
Tip position measurement that measures the relative unevenness in the radial direction of the outer peripheral edge portion of the bonded substrate at a plurality of points in the circumferential direction, and measures the relative tip position relationship of the outer peripheral edge between the two sets of substrates. Means,
From the detection result of the outermost edge measurement means, the contour shape data of one set of substrates is detected, and for the other set of substrates, the front end is based on the contour shape data of the one set of substrates. It obtains contour shape data from the relative tip position relationship between the measured two sets of substrates at the position measuring means, by comparing the contour shape data between the two sets of substrates, misalignment between the two sets of substrates An apparatus for detecting a positional deviation of a bonded substrate, comprising: a calculating means for obtaining an amount. The computing means is
From the detection result of the outermost edge measurement means, a first calculation means for detecting the contour shape data of any one of the sets and obtaining the diameter and the center position ;
Against the operation result of the previous SL first computing means, the tip position measuring means to control the relative tip position relationship measured, a third operation for obtaining the contour data of any other set of substrate Means,
Fourth calculation means for determining the diameter and center position of the other set of substrates from the calculation result of the third calculation means;
And a fifth calculation means for comparing the calculation result of the first calculation means with the calculation result of the fourth calculation means and detecting the shift amount of the center position between the two sets of substrates. The position shift detection apparatus of the bonding board | substrate of Claim 1 characterized by these. The tip position measuring means includes
Rotating means for mounting the bonded substrate and rotating it relatively,
Light is irradiated in the tangential direction of the bonded substrate to the vicinity of the outer peripheral edge of the bonded substrate, and with the rotation of the rotating means, a projected image of each point in the circumferential direction is taken, and the two sets The apparatus for detecting a positional deviation of a bonded substrate according to claim 1, further comprising a first optical system that detects relative unevenness between the substrates. The first optical system includes:
A point light source,
A collimator lens that creates parallel light by entering light from the point light source;
A condensing optical system for condensing light that has passed near the outer peripheral edge, and
The apparatus for detecting a positional deviation of a bonded substrate according to claim 3, further comprising: an image sensor that projects a shadow image of the light that has passed through the condensing optical system. The tip position measuring means includes
Rotating means for mounting the bonded substrate and rotating it relatively,
With respect to the vicinity of the outer peripheral edge of the bonded substrate, along with the rotation of the rotating means, slit light is irradiated in the radial direction of the bonded substrate to illuminate the bright line image from one or more directions, and the two sets the first position deviation detecting apparatus of stuck substrates according to claim 1, wherein further comprising a light cutting means for detecting the relative unevenness between substrate. The outermost edge measuring means is
Rotating means for mounting the bonded substrate and rotating it relatively,
For the vicinity of the outer peripheral edge of the bonded substrate, irradiate light in the thickness direction of the bonded substrate, and with the rotation of the rotating means, receive the light irradiated to the vicinity of the outer peripheral edge from the facing direction, 6. The misalignment detection device for a bonded substrate according to claim 1, further comprising: a second optical system that detects the contour shape of the bonded substrate as a whole. The outermost edge measuring means is
Rotating means for mounting the bonded substrate and rotating it relatively,
The vicinity of the outer peripheral edge of the bonded substrate is irradiated with light in the tangential direction of the bonded substrate, and as the rotating means rotates, a projected image of each point in the circumferential direction is taken, and the bonded substrate And a first optical system for detecting the contour shape as a whole. The apparatus for detecting a positional deviation of a bonded substrate according to any one of claims 1 to 5. The outermost edge measuring means is
Rotating means for mounting the bonded substrate and rotating it relatively,
With respect to the vicinity of the outer peripheral edge of the bonded substrate, along with the rotation of the rotating means, slit light is irradiated in the radial direction of the bonded substrate to illuminate the bright line image from one or more directions, and the two sets 6. A second light cutting means for making the position of the front end side of the substrate of the laminated substrate into a contour shape as the whole of the bonded substrate. 6. Position shift detection device for laminated substrates.   9. A semiconductor manufacturing method using the position shift detection device according to claim 1 and correcting an element formation position on the bonded substrate in response to a position shift detection result. apparatus. In a bonded substrate formed by stacking two disc-shaped substrates on top and bottom, a method for detecting a shift amount between the two substrates.
An outermost edge measuring step for detecting a contour shape as a whole combining the two sets of substrates;
Tip position measurement that measures the relative unevenness in the radial direction of the outer peripheral edge portion of the bonded substrate at a plurality of points in the circumferential direction, and measures the relative tip position relationship of the outer peripheral edge between the two sets of substrates. Steps,
From the detection result in the outermost edge measurement step, the contour shape data of one of the sets of substrates is detected, and the other set of substrates is based on the contour shape data of the one set of substrates, obtains contour shape data from the relative tip position relationship between two sets of substrates measured at tip position measuring step, by comparing the contour shape data between the two sets of substrates, between the two pairs of substrates And a calculation step for obtaining a deviation amount. The calculation step includes:
From the detection result in the outermost edge measurement step, a first calculation step for detecting the contour shape data of any one set of substrates and obtaining the diameter and the center position ;
Against the operation result of the previous SL first operation step, the tip position measuring said measured relative tip position-related control in step 3 to obtain the contour data of any other set of substrate The operation steps of
A fourth calculation step for obtaining the diameter and center position of the other set of substrates from the calculation result in the third calculation step;
A fifth calculation step for comparing a calculation result in the fourth calculation step with a calculation result in the first calculation step and detecting a shift amount of a center position between the two sets of substrates; The position shift detection method of the bonding board | substrate of Claim 10 characterized by the above-mentioned.

Images