JP2015122537A - Substrate overlapping device and substrate overlapping method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To verify accuracy of overlapping.SOLUTION: An overlapping device includes: a first stage which holds one of a plurality of substrates; a second stage which is disposed facing the first stage, is relatively movable to the first stage, and holds the others of the plurality of substrates; and an observation part which observes alignment marks of the one and the other substrates when positioning the one substrate and the other substrates in a state that the first stage and the second stage hold the plurality of substrates, and observes the alignment marks in a state that the plurality of overlapped substrates are separated from the first stage and are held by the second stage.

Description

  The present invention relates to a substrate overlaying apparatus.

There is a stacked semiconductor device in which a plurality of substrates are stacked and bonded (see Patent Document 1). In the case of bonding substrates, a plurality of substrates each having a semiconductor device are stacked and bonded to each other.
[Prior art documents]
[Patent Literature]
[Patent Document 1] JP-A-2005-251972

  When manufacturing a stacked semiconductor device, it is required to align the substrate with the accuracy of the line width level of the semiconductor device. However, since there are effects due to changes over time and environmental changes, it is required to verify the alignment accuracy in the overlay apparatus.

  In order to solve the above problems, as one aspect of the present invention, a first stage that holds one of a plurality of substrates, a first stage that is disposed opposite to the first stage, and a relative movement with respect to the first stage When possible, a second stage that holds another substrate among a plurality of substrates, and a first substrate and another substrate are aligned with the first stage and the second stage sandwiching the plurality of substrates. And an observation unit for observing alignment marks on one substrate and another substrate and observing the alignment marks in a state in which the plurality of stacked substrates are separated from the first stage and held on the second stage. A substrate overlay apparatus is provided.

  The above summary of the present invention does not enumerate all necessary features of the present invention. Sub-combinations of these feature groups can also be an invention.

1 is a schematic plan view of a production line 100. FIG. FIG. 3 is a schematic cross-sectional view of a superposition apparatus 200. FIG. 3 is a schematic cross-sectional view of a superposition apparatus 200. It is a figure which shows arrangement | positioning of the observation part 280. FIG. FIG. 3 is a schematic cross-sectional view of a superposition apparatus 200. 3 is a schematic cross-sectional view of a pressurizing device 330. FIG. FIG. 3 is a schematic cross-sectional view of a superposition apparatus 200. 2 is a schematic plan view of a production line 101. FIG. 2 is a schematic cross-sectional view of a superimposing device 201. FIG. 2 is a schematic cross-sectional view of a superimposing device 201. FIG. 3 is a schematic plan view of a production line 103. FIG. 3 is a schematic plan view of an observation unit 281. FIG. 6 is a schematic diagram for explaining the operation of an evaluation microscope 284. FIG.

  Hereinafter, the present invention will be described through embodiments of the invention, but the following embodiments do not limit the invention according to the claims. In addition, not all the combinations of features described in the embodiments are essential for the solving means of the invention.

  FIG. 1 is a schematic plan view of a production line 100 for a laminated semiconductor device. The production line 100 includes a normal temperature part 102 and a high temperature part 302 formed inside a common cover 130.

  The normal temperature unit 102 includes a control unit 110 and a plurality of FOUPs (Front Opening Unified Pods) 122, 124, and 126 on one end surface of the cover 130. The control unit 110 includes a control unit that controls the operation of the entire production line 100. In addition, the control unit 110 includes an operation unit that is operated by a user from the outside when the production line 100 is turned on and various settings are made. Furthermore, the control unit 110 may include a connection unit that connects to other devices additionally provided.

  Some of the FOUPs 124 and 126 accommodate a plurality of substrates 121 to be superposed and are loaded into the production line 100. The laminated substrate 123 manufactured by superimposing the substrates 121 in the manufacturing line 100 is accommodated in another FOUP 122 and carried out of the manufacturing line 100. As a result, the plurality of substrates 121 can be loaded into the production line 100 all at once, and the plurality of laminated substrates 123 can be unloaded from the production line 100 all at once.

  Note that the substrate 121 used for superposition in the superposition apparatus 200 can be a glass substrate or the like in addition to a semiconductor wafer such as a silicon single crystal wafer or a compound semiconductor wafer. In addition, at least one of the substrates 121 used for superposition may include a plurality of elements. Further, one or both of the substrates 121 to be superposed may be a laminated substrate 123 that is already manufactured by superimposing wafers.

  The room temperature unit 102 includes loaders 140, 162, 164, a pre-aligner 150, a holder rack 170, and a superimposing device 200. The inside of the room temperature unit 102 is temperature-managed so as to maintain substantially the same temperature as the room temperature of the environment where the production line 100 is installed. Thereby, since the operation accuracy of the superimposing apparatus 200 is stabilized, the alignment accuracy in the case of superimposing the substrates 121 is improved.

  The loader 140 arranged facing the FOUPs 122, 124, 126 carries the substrate out of the FOUPs 124, 126. In addition, the loader 140 carries the laminated substrate 123 into the FOUP 122. Thus, the loader 140 directly conveys the substrate 121 or the laminated substrate 123.

  The pre-aligner 150 mounts the substrate 121 carried out from the FOUPs 124 and 126 by the loader 140 on the substrate holder 125. The substrate holder 125 is transported from the holder rack 170 to the pre-aligner 150 by loaders 164 and 162.

  The substrate holder 125 is made of a material having high rigidity and heat resistance, and has a flat holding surface. The substrate holder 125 has a holding function such as an electrostatic chuck and holds the substrate 121 or the laminated substrate 123. Thereby, the substrate 121 or the laminated substrate 123 can be handled integrally with the substrate holder 125.

  Since many of the substrates 121 are formed of a thin and brittle material, the operation is facilitated by handling them integrally with the highly rigid substrate holder 125. In addition, as a material of the substrate holder 125, ceramics, such as an alumina, can be illustrated as a suitable material.

  In the pre-aligner 150, simple alignment of the substrate 121 with respect to the substrate holder 125 is also executed. As a result, the mounting position and mounting direction of the substrate 121 with respect to the substrate holder 125 become constant, and the burden of alignment in the overlay apparatus 200 described later is reduced. The substrate 121 mounted on the substrate holder 125 in the pre-aligner 150 is transported together with the substrate holder 125 by the loader 162 disposed along the overlaying device 200 and is carried into the overlaying device 200.

  The overlapping apparatus 200 includes a fixed stage assembly 240 and a moving stage assembly 250 arranged inside the frame body 210. The fixed stage assembly 240 is fixed to the frame body 210 and holds the substrate holder 125 and the substrate 121 downward. The moving stage assembly 250 carries the substrate holder 125 and the substrate 121 and moves relative to the fixed stage assembly 240 inside the superposition apparatus 200.

  The outer surface of the frame body 210 is closed by the wall material 220, and the influence of the radiant heat from the surroundings on the overlapping apparatus 200 is cut off. An interferometer 260 is disposed inside the wall member 220, and the position of the moving stage assembly 250 is measured with high accuracy using a reflecting mirror mounted on the moving stage assembly 250. Thereby, a pair of board | substrate 121 can be aligned with high precision.

  The substrate 121 superposed in the superposing device 200 is unloaded from the superposing device by the loader 162 and is carried into the load lock 320 by the loader 164. The substrate 121 carried into the load lock 320 is processed in the high temperature unit 302 described below.

  A holder rack 170 is disposed in the vicinity of the loader 164. The holder rack 170 accommodates a plurality of substrate holders 125. In addition, the holder rack 170 may have a function of cooling the substrate holder 125.

  The high temperature part 302 is surrounded by the heat insulating wall 310, maintains a high internal temperature, and blocks heat radiation to the outside. The high temperature unit 302 includes a load lock 320, a pressure device 330, and a loader 340. The load lock 320 has shutters 322 and 324 that open and close alternately, and prevents the high temperature atmosphere of the high temperature part 302 from leaking to the normal temperature part 102.

  The substrate 121 carried into the load lock 320 is carried into one of a plurality of pressure devices 330 by the loader 340. The pressurizing device 330 presses the superposed substrate 121 and permanently bonds the substrate 121 together. Thus, the substrate 121 becomes the laminated substrate 123.

  The laminated substrate 123 is unloaded from the pressurizing device 330 by the loader 340 and is loaded into the load lock 320 from the high temperature unit 302 side. The laminated substrate 123 is unloaded from the load lock 320 by the loader 164 on the room temperature unit 102 side, and is detached from the substrate holder 125 on the top plate of the holder rack 170. Thus, the laminated substrate 123 and the substrate holder 125 are separated, and the substrate holder 125 is conveyed to the holder rack 170, and the laminated substrate 123 is conveyed to the FOUP 122.

  FIG. 2 is a schematic cross-sectional view of the overlay apparatus 200. As already described, the superimposing apparatus 200 includes the fixed stage assembly 240 and the moving stage assembly 250 arranged inside the frame body 210. The frame body 210 is made of a highly rigid material, and does not deform even when a reaction force is applied due to the operation of the overlapping device 200.

  The fixed stage assembly 240 includes a load cell 245, a fixed stage 248, and an observation unit 280. Observation unit 280 further includes an alignment microscope 282 and an evaluation microscope 284.

  The fixed stage 248 is suspended from the ceiling surface of the frame 210 via a plurality of load cells 245. The fixed stage 248 includes an electrostatic chuck 249, and holds the substrate holder 125 holding the substrate 121 by attracting it to the lower surface.

  The plurality of load cells 245 detect a load applied upward from below with respect to the fixed stage 248. Thereby, the control unit 110 can detect that a load that causes the fixed stage 248 to tilt is generated by comparing the detection results of the plurality of load cells 245.

  Further, the fixed stage 248 has a plurality of transparent portions 247 that are optically transparent. The transparent part 247 is formed through the fixed stage 248 in the thickness direction. The substrate holder 125 is also formed with a transparent portion 127 corresponding to the position of the transparent portion 247 of the fixed stage 248. Thereby, as shown by a dotted line in the drawing, the lower surface side of the fixed stage 248 can be observed from the upper surface side of the fixed stage 248 through the transparent portion 247.

  The transparent portions 127 and 247 are filled with a material that is at least optically transparent to infrared rays, not a hole penetrating the substrate holder 125 or the fixed stage 248. Thereby, the lower surface holding the substrate 121 or the substrate holder 125 in the substrate holder 125 and the fixed stage 248 becomes flat.

  For example, a silicon single crystal substrate transmits infrared rays. Therefore, when the substrate 121 is a silicon single crystal substrate or a circuit manufactured using a silicon single crystal substrate as a material, the alignment microscope 282 transmits the substrate 121 by illuminating the lower portion of the fixed stage 248 with infrared rays. The alignment mark can be observed. Even when the fixed stage 248 holds the substrate 121, the alignment microscope 282 can observe up to the lower side of the substrate 121 held on the fixed stage 248. Therefore, the alignment microscope 282 can observe the alignment mark of the substrate 121 held on the fine movement stage 258 when the fine movement stage 258 moves directly below the fixed stage 248.

  The alignment microscope 282 is fixed downward on the upper surface of the frame body 210. A through-hole 212 is formed in the frame 210 immediately below the alignment microscope 282. Therefore, the alignment microscope 282 can observe the inside of the frame 210 through the through hole 212.

  Further, a transparent portion 247 of the fixed stage 248 is disposed immediately below the alignment microscope. Further, as indicated by a dotted line in the figure, the alignment microscope 282 has a focal point near the lower surface of the substrate 121 held by the fixed stage 248. Therefore, the alignment microscope 282 can observe the lower surface side of the fixed stage 248 through the frame body 210 and the fixed stage 248. The evaluation microscope 284 arranged between the pair of alignment microscopes 282 will be described later with reference to the next drawing.

  The moving stage assembly 250 includes a moving surface plate 252, a coarse moving stage 254, a spherical seat 256 and a fine moving stage 258. The movable surface plate 252 is movably disposed on the guide rail 251 disposed on the inner bottom surface of the frame body 210. The coarse moving stage 254 moves horizontally with respect to the moving surface plate 252 in the X and Y directions indicated by arrows in the drawing.

  The fine movement stage 258 is supported by the spherical seat 256, translates in the X axis, Y axis, and Z axis directions with respect to the coarse movement stage 254, and rotates around the X axis, Y axis, and Z axis. However, the movement range of fine movement stage 258 is as small as about several μm to several tens of μm. The fine movement stage 258 includes an electrostatic chuck 259, and holds the substrate holder 125 holding the substrate 121 by attracting it to the upper surface. Therefore, even if the moving stage assembly 250 operates with the substrate holder 125 and the substrate 121 held, the substrate holder 125 and the substrate 121 do not fall off the fine movement stage 258.

  The alignment marks provided on the substrate 121 are not limited to those formed on the surface of the substrate 121 for the purpose of using them as alignment marks from the beginning. For example, a semiconductor device, wiring, via hole, or the like formed or mounted on the substrate 121 may be used.

  FIG. 3 is a schematic cross-sectional view of the overlay apparatus 200. FIG. 3 shows a state seen from the direction of arrow A shown in FIG. Here, the direction indicated by the arrow A is parallel to the moving direction of the moving stage assembly 250 with respect to the frame 210. In FIG. 3, the same elements as those in FIG. 2 are denoted by the same reference numerals, and redundant description is omitted.

  In FIG. 3, it can be seen that a plurality of evaluation microscopes 284 that are viewed as one overlapping in the observation unit 280 of FIG. 2 are arranged. Further, it can be seen that immediately below the evaluation microscope 284, the through-hole 212 is disposed in the frame 210, and the transparent portions 247 and 127 are disposed in the fixed stage 248 and the substrate holder 125, respectively.

  Accordingly, the evaluation microscope 284 can also observe the substrate 121 held on the fixed stage 248 from above the frame body 210. Further, when the substrate 121 is a silicon single crystal substrate, the evaluation microscope 284 is fixed even when the fixed stage 248 holds the substrate 121 by illuminating the lower portion of the fixed stage 248 with infrared rays. Observation is possible down to the lower side of the substrate 121 held on the stage 248.

  FIG. 4 is a plan view of the observation unit 280 and shows the arrangement of the alignment microscope 282 and the evaluation microscope 284. As shown by the arrow C in FIG. 3, the frame 210 is shown as viewed from above. In FIG. 4, the same reference numerals are given to the same elements as those in FIGS. 2 and 3, and redundant description is omitted.

  As illustrated, the alignment microscope 282 and the evaluation microscope 284 in the observation unit 280 are arranged at different positions both in the direction of the arrow A and in the direction of the arrow B. The alignment microscope 282 is arranged in the direction of arrow A parallel to the moving direction of the moving stage assembly 250. In contrast, the evaluation microscopes 284 are arranged in the direction of the arrow B orthogonal to the arrow A.

As a result, the alignment microscope 282 can be arranged with a gap D ₁ wider than the gap D ₂ of the evaluation microscope 284. Therefore, the alignment microscope 282 can align the substrate 121 with higher accuracy. Further, by narrowing the interval between the evaluation microscopes 284, the width of the superimposing apparatus 200 in the arrow B direction can be reduced.

  FIG. 5 is a cross-sectional view of the superimposing apparatus 200, and shows a state seen from the same direction as FIG. However, with respect to the state shown in FIG. 2, the position of the moving stage assembly 250 changes, and the fixed stage 248 and the fine movement stage 258 face each other. In FIG. 5, the same reference numerals are given to elements common to the other drawings, and redundant description is omitted.

  In the state shown in the figure, the fine movement stage 258 faces the fixed stage 248 and the fine movement stage 258 is raised. As a result, the substrate 121 held on the fixed stage 248 is approaching until just before contacting the substrate 121 held on the fine movement stage 258. Therefore, the surfaces of the pair of substrates 121 are both included in the depth of field of the alignment microscope 282. In other words, the alignment microscope 282 has a depth of field that is wider than the interval between the substrates 121 immediately before superposition.

  By observing the alignment marks formed on the respective surfaces of the substrate 121 with the alignment microscope 282 in the above state, the relative positions of the pair of substrates 121 can be measured. Therefore, the control unit 110 moves the fine movement stage 258 so as to eliminate the deviation of the measured relative position. Thereby, the pair of substrates 121 can be aligned.

  Furthermore, the aligned substrates 121 can be superimposed by further raising the fine movement stage 258 while the pair of substrates 121 are aligned. Here, since the pair of substrates 121 to be aligned are already close to each other, even if the fine movement stage 258 is raised from the state, the alignment hardly shifts. Further, when the substrates 121 come into contact with each other, an impact that damages the substrates does not occur.

  Thus, the pair of substrates 121 are aligned and overlapped in the overlapping device 200. As already described, in the production line 100, the pair of stacked substrates 121 are pressed by the pressing device 330 and fixed to each other.

  In the above example, the observation unit 280 has the alignment microscope 282 and the evaluation microscope 284 separately. However, the observation section can be formed by a common microscope that can also be used for alignment and evaluation.

  That is, by using a microscope having an optical system with a deep focal depth, the alignment microscope 282 and the evaluation microscope 284 can also be used. If the depth of field of the microscope is deep, even when the fixed stage 248 and the fine movement stage 258 are separated from each other to align the substrate 121, the fixed stage 248 and the fine movement stage 258 are close to each other and the substrate 121 is positioned. In any case, the alignment mark on the substrate 121 can be observed with a single microscope even when the substrate holder 125 and the substrate holder 125 are superimposed on each other. The alignment microscope 282 and the evaluation microscope 284 are also used when the microscope is provided so as to be movable at least in the Z direction in the figure, and the fixed stage 248 has a structure retracted from directly below the microscope. it can.

  FIG. 6 is a cross-sectional view of the pressure device 330. The pressure device 330 includes a surface plate 338 and a heater plate 336 that are sequentially stacked from the bottom of the housing 332, and a pressure lower portion 334 and a heater plate 336 that are suspended from the ceiling surface of the housing 332. Each of the heater plates 336 includes a heater. An opening 331 is provided on one of the side surfaces of the housing 332.

  A substrate 121 that has already been aligned and stacked, and a pair of substrate holders 125 that sandwich the substrate 121 are carried into the pressure device 330. The loaded substrate holder 125 and the substrate 121 are placed on the upper surface of the heater plate 336 of the surface plate 338.

  First, the pressurizing device 330 raises the temperature of the heater plate 336 and lowers the lower portion 334 to push down the upper heater plate 336. As a result, the substrate holder 125 and the substrate 121 sandwiched between the heater plates 336 are heated and pressed to be bonded, and the substrate 121 becomes the laminated substrate 123. The manufactured laminated substrate 123 is sequentially stored in the FOUP 122 as described above.

  In view of the above-described applications, the substrate holder 125 is required to have strength and heat resistance that do not deteriorate even if the heating and pressurization in the pressurizing device 330 are repeatedly performed. In addition, when the heating temperature by the heater plate 336 is high, the surface of the substrate 121 may chemically react with the atmosphere. Therefore, when the substrate 121 is heated and pressurized, the inside of the housing 332 is preferably evacuated to a vacuum environment. For this reason, an openable / closable door that hermetically closes the opening 331 may be provided.

  Further, the pressurizing device 330 may be further provided with a cooling unit that cools the laminated substrate 123 after being heated and pressurized. Thereby, even if it does not reach room temperature, the laminated substrate 123 cooled to some extent can be carried out and quickly returned to the FOUP 122.

  The manufacturing line 100 shown in FIG. 1 continuously manufactures the multilayer substrate 123 by repeating a series of processes as described above. However, the alignment accuracy of the overlaying apparatus 200 may change due to changes over time in each part of the production line 100 and changes in the environment. Further, due to the deterioration of the pressurizing device 330, the pressurization by the pressurizing device 330 may cause the alignment of the substrate 121 to shift.

  Therefore, after the superposition of the substrates by the superimposing apparatus 200 is completed, or after the substrate 121 becomes the laminated substrate 123 by the pressure device 330, it is required to evaluate the alignment state of the substrate 121 again. Such alignment evaluation can be executed in the overlay apparatus 200 using the evaluation microscope 284.

  FIG. 7 is a schematic cross-sectional view of the superposition apparatus 200, and shows a state seen from the same direction as FIG. In FIG. 7, the same reference numerals are given to elements common to the other drawings, and redundant description is omitted.

  However, as compared with the state shown in FIG. 3, the multilayer substrate 123 is mounted on the fine movement stage 258. Further, the fixed stage 248 does not hold the substrate holder 125, the substrate 121, or the laminated substrate 123.

  In the state shown in the figure, when the inside of the laminated substrate 123 is observed with the alignment microscope 282 having a focus near the lower surface of the fixed stage 248, the upper surface of the laminated substrate 123 may come into contact with the fixed stage 248. However, the evaluation microscope 284 has a focal point near the joint surface of the laminated substrate 123 mounted on the lowered fine movement stage 258.

  Therefore, the alignment mark on the joint surface of the laminated substrate 123 can be observed with the evaluation microscope 284 while illuminating with infrared rays. Since the alignment mark is provided on each of the superposed substrates 121, the alignment accuracy of the laminated substrate 123 can be detected by the observation as described above.

  In other words, the evaluation microscope 284 has an optical system that includes the substrate 121 that is superimposed and spaced from the fixed stage 248 within the depth of focus. Therefore, when the substrate 121 or the laminated substrate 123 is observed with the evaluation microscope 284, the substrate 121 or the laminated substrate 123 does not come into contact with the fixed stage 248, the alignment microscope 282, or the like.

  Thereby, for example, the alignment state can be confirmed by observing the substrate 121 superimposed in the superimposing apparatus 200 with the evaluation microscope 284 again. Thereby, when the alignment accuracy is lower than the assumed threshold value, the substrate 121 can be discarded or re-superposed without turning to the pressurizing device.

  Further, by moving the fine movement stage 258, an arbitrary region of the laminated substrate 123 on the fine movement stage 258 can be observed with the evaluation microscope 284. Therefore, the alignment accuracy can be verified in a wide range on the multilayer substrate 123 as well as the alignment accuracy at a specific position. It is also possible to know the distribution of alignment accuracy in the laminated substrate 123.

  Furthermore, the state of the pressure device 330 can be evaluated by evaluating with the evaluation microscope 284 in a state where the pressure device 330 is made the laminated substrate 123. That is, when the substrate that is accurately aligned in the superimposing apparatus 200 is displaced in the pressurizing apparatus 330, the pressurizing apparatus 330 may have a deviation in temperature distribution, pressure distribution, or the like. I understand.

  In view of the above applications, it is desirable that the resolution of the evaluation microscope 284 is higher than the resolution of the alignment microscope 282. Moreover, you may perform the above evaluations with respect to the total number of the board | substrate 121 or the laminated substrate 123 according to the quality calculated | required by the product. Further, the evaluation may be performed on some of the substrates 121 or the laminated substrates 123.

  Further, the fixed stage 248 is not involved at all in the evaluation of the substrate 121 or the laminated substrate 123 by the evaluation microscope 284. Therefore, when using the evaluation microscope 284, the fixed stage 248 may be retracted from the visual field of the evaluation microscope 284.

  FIG. 8 is a plan view of the production line 101. The production line 101 has the same structure as the production line 100 except for the parts described below. Therefore, the same reference numerals are assigned to elements common to the production line 100, and redundant description is omitted.

  The production line 101 has an opening 132 on the side surface of the cover 130. The production line 101 also includes a shutter 134 that closes or opens the opening 132. When the shutter 134 is opened, the opening 132 allows the room temperature unit 102 to communicate with the outside on the side of the holder rack 170.

  A relay unit 180 is disposed outside the opening 132. The relay unit 180 includes a housing 182 having a pair of openings 181 and 183, and a loader 184 accommodated in the housing 182. The loader 184 transports the substrate 121 or the laminated substrate 123 from one outer side of the openings 181 and 183 to the other outer side.

  Further, the relay unit 180 is installed so that one opening 181 communicates with the opening 132 of the cover 130. The other opening 183 of the relay unit 180 communicates with the opening 217 of the overlapping device 201 that is installed adjacently. As a result, the loader 184 of the relay unit 180 transports the substrate 121 or the laminated substrate 123 between the production line 101 and the stacking apparatus 201.

  That is, the loader 184 can deliver the loader 164 of the production line 101 to the substrate holder 125, the substrate 121, or the laminated substrate 123. Therefore, the loader 184 can transport the substrate 121 superimposed by the superimposing device 200 of the production line 101 or the laminated substrate 123 manufactured by the pressurizing device 330 to the superimposing device 201. Further, the substrate 121 or the laminated substrate 123 can be transported from the stacking apparatus 201 to the production line 101.

  Thereby, for example, the substrate 121 superimposed in the superimposing apparatus 200 can be observed again by the evaluation microscope 284 of the superimposing apparatus 201, and the alignment state can be confirmed. When the alignment accuracy is lower than the assumed threshold, the substrate 121 can be discarded or subjected to superposition again without being transported to the pressure device 330. In addition, maintenance of the production line 101 can be recommended to the user.

  Moreover, the state of the pressurizing device 330 can be evaluated by evaluating with the evaluation microscope 284 in a state where the pressurizing device 330 is used as the laminated substrate 123. That is, when the substrate that is accurately aligned in the superimposing apparatus 200 is displaced in the pressurizing apparatus 330, the pressurizing apparatus 330 may have a deviation in temperature distribution, pressure distribution, or the like. I understand. Therefore, the user can be encouraged to replace or maintain the pressurizing device 330.

  Further, the loader 184 of the relay unit 180 transports the substrate holder 125 on which the substrate 121 or the laminated substrate 123 is mounted inside a housing 182 that has nothing other than the loader 184. Therefore, a large acceleration is given to the substrate holder 125 holding the substrate 121 or the laminated substrate in the relay unit 180, and then the displacement of the substrate 121 or the laminated substrate 123 is measured by the evaluation microscope 284, whereby the holding force of the substrate holder 125 is measured. Can be evaluated.

  Furthermore, in the production line 101, when the overlay apparatus 200 cannot be moved for some reason, the overlay apparatus 201 can be temporarily connected and the operation of the production line 101 can be continued. Thereby, the operation rate of the manufacturing line 101 can be improved and the productivity of the laminated substrate 123 can be improved.

  FIG. 9 is a cross-sectional view of the overlay device 201. The superposition apparatus 201 has the same structure as the superposition apparatus 200 except for the parts described below. Therefore, the same elements as those of the superposition apparatus 200 are denoted by the same reference numerals, and redundant description is omitted.

  The superimposing device 201 is formed inside a frame body 211 having a space divided into three upper and lower stages. The frame body 211 has a handle 213 on the side surface. Further, the frame 211 has casters 219 on the lower surface. Thereby, the superimposing apparatus 201 can be moved by pushing or pulling the handle 213.

  In the superimposing apparatus 201, the inner side of the middle stage of the frame body 211 has the same structure as the inner side of the frame body 210 of the overlapping apparatus 200. However, an opening 217 is formed at one end of the frame 211 on the left side in the drawing. The opening 217 has a shutter 215 that opens and closes. When the shutter 215 is open, the opening 217 has a size that allows the substrate 121 or the laminated substrate 123 to pass therethrough.

  In the superimposing apparatus 201, the height H from the floor surface of the lowered fine movement stage 258 has the same height as the transport path of the substrate holder 125, the substrate 121, or the laminated substrate 123 in the production line 101 described later. Thereby, it becomes easy to carry in or carry out the substrate 121 or the laminated substrate 123 with respect to the stacking apparatus 201.

  In the superimposing apparatus 201, the control unit 111 is housed in the upper stage of the frame 211 together with the observation unit 280 including the alignment microscope 282 and the evaluation microscope 284. Thereby, the alignment microscope 282 and the evaluation microscope 284 are protected by the frame body 211. The control unit 111 controls the operation of the superimposing apparatus 201 and communicates with a manufacturing line 101 described later to operate the manufacturing line 101 and the superimposing apparatus 201 in cooperation with each other.

  In the superimposing apparatus 201, the power supply unit 113 and the light source unit 115 are accommodated in the lower stage of the frame body 211. The power supply unit 113 supplies a power to each unit of the superposition apparatus 201 including a transformer and the like. Note that a battery may be mounted on the power supply unit 113 so that the superimposing apparatus 201 operates independently without being supplied with power from the outside.

  The light source unit 115 receives the supply of power from the power source unit 113 and generates infrared rays. The infrared rays generated by the light source unit 115 illuminate the substrate 121 or the laminated substrate 123 held by the fixed stage 248 and the fine movement stage 258. Thereby, the alignment mark or the like can be observed through the silicon single crystal substrate or the like by the alignment microscope 282 and the evaluation microscope 284.

  Therefore, even in the state shown in the drawing, the alignment mark of the substrate 121 held on the fixed stage 248 can be observed by the alignment microscope 282. Further, when fine movement stage 258 moves directly below fixed stage 248, alignment microscope 282 can observe the alignment mark of substrate 121 held on fine movement stage 258.

  FIG. 10 is a cross-sectional view of the superimposing apparatus 201 and shows a state seen from the direction of the arrow E shown in FIG. Elements that are the same as those in FIG. 9 are given the same reference numerals, and redundant descriptions are omitted.

  FIG. 10 shows a state in which the substrate holder 125 and the laminated substrate 123 held on the fine movement stage 258 are observed with the evaluation microscope 284. The state of fine movement stage 258 and laminated substrate 123 is the same as that of superposition apparatus 200 shown in FIG.

  That is, the evaluation microscope 284 observes the lower part of the fixed stage 248 through the through hole 212 and the transparent part 247. Further, the evaluation microscope 284 can observe the inside of the multilayer substrate 123 through the transparent portion 127 of the substrate holder 125.

  Here, the evaluation microscope 284 has a focal point on the bonding surface of the laminated substrate 123 held by the fine movement stage 258 that is lowered and separated from the fixed stage 248. Further, the laminated substrate 123 in the superimposing apparatus 201 is illuminated with infrared rays supplied from the light source unit 115.

  Therefore, the evaluation microscope 284 can observe the alignment mark located on the bonding surface through the substrate holder 125 and the laminated substrate 123. Further, even when the fine movement stage 258 is raised and the substrate 121 or the laminated substrate 123 is sandwiched between the fixed stage 248 and the fine movement stage 258, the alignment mark of the substrate 121 is marked by the alignment microscope 282 or the evaluation microscope 284. Observable.

  Note that in the case of evaluating the alignment in the laminated substrate 123, the substrate 121 forming the laminated substrate 123 is already bonded. Therefore, you may observe with the evaluation microscope 284 in the state which removed the upper substrate holder 125. FIG.

  FIG. 11 is a plan view of the production line 103. The production line 103 has the same structure as the production line 100 shown in FIG. 1 and the production line 101 shown in FIG. 7 except for the parts described below. Therefore, the same reference numerals are assigned to the same elements as those in the production lines 100 and 101, and duplicate descriptions are omitted.

  In the production line 103, the loader 164 arranged in the vicinity of the load lock 320 in the room temperature unit 102 is arranged closer to the left side in the drawing than the other production lines 100 and 101. For this reason, the holder rack 170 is arranged close to the right side in the drawing.

  Further, in the production line 103, the overlapping device 201 disposed outside the cover 130 is coupled to the opening 132 without the relay unit 180 interposed. For this reason, compared with the production line 101, the superposition apparatus 201 changes the direction by 90 °. The loader 164 of the room temperature unit 102 takes in and out the substrate 121 or the laminated substrate 123 with respect to the superimposing apparatus 201.

  With this arrangement, the relay unit 180 can be omitted and the number of elements in the production line 103 can be reduced. This also simplifies control when operating the production line 103. In addition, since the side surface of the cover 130 is widely open on the side where the superimposing device 201 is disposed, the maintainability of the superposing device 200 inside the normal temperature unit 102 and the pressurizing device 330 of the high temperature unit 302 is improved.

  In the above example, the superimposing apparatus 201 has a structure that is detachable from the production line 103. However, the cover 130 of the production line 103 and the outer shell of the superimposing device 201 may be integrated. In that case, the shutter 215 and the like can be omitted.

  FIG. 12 is a diagram schematically illustrating the structure of another observation unit 281. The observation unit 281 has the same structure as the observation unit 280 shown in FIG. 4 except for the parts described below. Therefore, the same elements as those of the observation unit 280 are denoted by the same reference numerals, and redundant description is omitted.

  The observation unit 281 has a structure unique to the arrangement of the evaluation microscope 284. In other words, in the observation unit 281, the pair of evaluation microscopes 284 are disposed horizontally and perpendicular to each other in the tangential direction of the fixed stage 248.

  FIG. 13 is a schematic plan view of the observation unit 281. In the observation unit 281, the pair of evaluation microscopes 284 are horizontally disposed at substantially the same height as the substrate holder 125 and the substrate 121 held on the fixed stage 248. When fine movement stage 258 faces fixed stage 248, substrate holder 125 and substrate 121 mounted on fine movement stage 258 are positioned at substantially the same height. In other words, the evaluation microscope 284 has a field of view over which the pair of substrates 121 stacked on each other and the pair of substrate holders 125 sandwiching the pair of substrates can be seen.

  Thereby, the evaluation microscope 284 can observe the position of the edge of the substrate 121 or the substrate holder 125 held by the fixed stage 248. Further, when fine movement stage 258 faces fixed stage 248, the position of the edge of substrate holder 125 or substrate 121 held by fine movement stage 258 can be observed.

  Thereby, for example, by observing the relative position of the substrate holder 125 immediately after the superposition by the superposition apparatus 200 and immediately after the pressurization by the pressurization apparatus 330, the displacement of the substrate 121 generated in the pressurization apparatus 330 is observed. Can be evaluated. Further, by observing the relative position of the substrate holder 125 before and after the transfer by the loaders 162 and 164, the displacement of the substrate 121 due to the transfer can be evaluated.

  Further, these evaluations can evaluate the alignment accuracy of the substrate 121 by observing the substrate holder 125 or the substrate 121 from the side even when the fixed stage 248 and the fine movement stage 258 face each other. Even when the alignment mark is not present on the substrate 121, the alignment of the substrate 121 can be evaluated.

  As mentioned above, although this invention was demonstrated using embodiment, the technical scope of this invention is not limited to the range as described in the said embodiment. It will be apparent to those skilled in the art that various modifications or improvements can be added to the above-described embodiment. It is apparent from the scope of the claims that the embodiments added with such changes or improvements can be included in the technical scope of the present invention.

  The order of execution of each process such as operations, procedures, steps, and stages in the apparatus, system, program, and method shown in the claims, the description, and the drawings is particularly “before” or “prior to”. It should be noted that the output of the previous process may be realized in any order unless used in a subsequent process. Regarding the operation flow in the claims, the description, and the drawings, even if it is described using “first”, “next”, etc. for convenience, it means that it is essential to carry out in this order. It is not a thing.

100, 101, 103 Production line, 102 Normal temperature part, 110, 111 Control part, 113 Power supply part, 115 Light source part, 121 Substrate, 122, 124, 126 FOUP, 123 Laminated substrate, 125 Substrate holder, 127, 247 Transparent part, 130 Cover, 132, 181, 183, 217, 331 Opening, 134, 215, 322, 324 Shutter, 140, 162, 164, 184, 340 Loader, 150 Pre-aligner, 170 Holder rack, 180 Relay unit, 182, 332 Housing , 200, 201 Overlay device, 210, 211 Frame, 212 Through hole, 213 Handle, 219 Casters, 220 Wall material, 240 Fixed stage assembly, 245 Load cell, 248 Fixed stage, 249, 259 Electrostatic chuck, 250 Moving stage assembly, 251 guide rail, 252 moving surface plate, 254 coarse movement stage, 256 spherical seat, 258 fine movement stage, 260 interferometer, 280, 281 observation section, 282 alignment microscope, 284 evaluation microscope, 302 high temperature section, 310 Insulating wall, 320 Load lock, 330 Pressurizer, 334 Inferior part, 336 Heater plate, 338 Surface plate

Claims (12)

A first stage for holding a first substrate;
A second stage disposed opposite to the first stage and movable relative to the first stage and holding a second substrate;
The first substrate and the second substrate spaced apart from each other when the first substrate held on the first stage and the second substrate held on the second stage are aligned with each other An alignment microscope for observing at least one of the alignment marks, and an observation unit having an evaluation microscope for observing the alignment marks in a state where the first substrate and the second substrate are superimposed on each other,
The substrate superposing apparatus in which the resolution of the evaluation microscope is higher than the resolution of the alignment microscope. The alignment microscope includes the alignment mark within a depth of focus when aligning the first substrate and the second substrate;
2. The evaluation microscope according to claim 1, wherein the evaluation microscope is provided separately from the alignment microscope, and includes the alignment mark within a depth of focus in a state where the first substrate and the second substrate are overlapped with each other. Substrate overlay device. The second stage is movable in a first direction parallel to the overlapping surface of the first substrate and the second substrate and in a second direction orthogonal to the first direction,
The substrate superposition apparatus according to claim 2, wherein a plurality of the evaluation microscopes are arranged along the first direction.   In the case where the alignment mark is observed by the observation unit in a state where the first substrate and the second substrate that are superimposed are held on the second stage and are separated from the first stage, the first stage The substrate superposition apparatus according to claim 1, wherein the substrate is retracted in a surface direction of the first substrate and the second substrate.   The evaluation microscope includes the alignment mark in a state where the first substrate held on the first stage and the second substrate held on the second stage are separated from each other within a depth of focus, and 2. The apparatus according to claim 1, wherein a focal depth position is variable so that the alignment mark in a state where the first substrate and the second substrate are superimposed is included within a focal depth. The first substrate is held on the first stage via a first substrate holder that is detachable from the first stage;
The substrate according to any one of claims 1 to 5, wherein the first substrate holder has an observation hole for observing an overlapping surface of the first substrate and the second substrate from the first stage side. Overlay device. A first stage for holding a first substrate;
A second stage disposed opposite to the first stage and movable relative to the first stage and holding a second substrate;
The relative position between the first substrate and the second substrate is measured before the first substrate held on the first stage and the second substrate held on the second stage are overlapped. An overlay measurement unit, and a measurement unit having an evaluation measurement unit that measures the relative position in a state where the first substrate and the second substrate are superimposed on each other,
A substrate overlaying apparatus in which the resolution of the evaluation measurement unit is higher than the resolution of the overlay measurement unit. A first holding step for holding the first substrate on the first stage;
A second holding step for holding the second substrate on a second stage that is disposed opposite to the first stage and is relatively movable with respect to the first stage;
Before the first substrate held on the first stage and the second substrate held on the second stage are superposed, the first substrate and the second substrate by a first measuring means A first measurement step for measuring the relative position of
A second measuring step of measuring the relative position by a second measuring means in a state where the first substrate and the second substrate are overlapped with each other,
The substrate overlaying method, wherein the resolution of the first measuring means is higher than the resolution of the second measuring means. A first stage for holding a first substrate;
A second stage disposed opposite to the first stage and movable relative to the first stage and holding a second substrate;
The first substrate and the second substrate in a state where the first substrate held on the first stage and the second substrate held on the second stage are aligned and overlapped with each other And a measurement unit having an evaluation measurement unit that measures the relative position in a state where the superimposed first substrate and second substrate are bonded to each other. ,
A substrate overlaying apparatus in which the resolution of the evaluation measurement unit is higher than the resolution of the overlay measurement unit. A first holding step for holding the first substrate on the first stage;
A second holding step for holding the second substrate on a second stage that is disposed opposite to the first stage and is relatively movable with respect to the first stage;
The first substrate held by the first stage and the second substrate held by the second stage are aligned with each other and overlapped with each other by the first measuring means. And a first measurement step for measuring a relative position of the second substrate;
A second measuring step of measuring the relative position by a second measuring means in a state where the superimposed first substrate and the second substrate are bonded to each other,
The substrate overlaying method, wherein the resolution of the first measuring means is higher than the resolution of the second measuring means. A first stage for holding a first substrate;
A second stage disposed opposite to the first stage and movable relative to the first stage and holding a second substrate;
The relative position between the first substrate and the second substrate is measured before the first substrate held on the first stage and the second substrate held on the second stage are overlapped. A measurement unit including an overlay measurement unit, and an evaluation measurement unit that measures the relative position in a state where the first substrate and the second substrate that are superimposed are bonded to each other;
A substrate overlaying apparatus in which the resolution of the evaluation measurement unit is higher than the resolution of the overlay measurement unit. A first holding step for holding the first substrate on the first stage;
A second holding step for holding the second substrate on a second stage that is disposed opposite to the first stage and is relatively movable with respect to the first stage;
Before the first substrate held on the first stage and the second substrate held on the second stage are superposed, the first substrate and the second substrate by a first measuring means A first measurement step for measuring the relative position of
A second measuring step of measuring the relative position by a second measuring means in a state where the superimposed first substrate and the second substrate are bonded to each other,
The substrate overlaying method, wherein the resolution of the first measuring means is higher than the resolution of the second measuring means.

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