JP2011216833A - Substrate overlapping device, substrate holder, substrate overlapping system, method of overlapping substrate, and method of manufacturing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To align and overlap substrates.SOLUTION: A substrate overlapping device includes: an operating force control unit for allowing operating force to operate on at least one of a first substrate and a second substrate; and an overlap unit for alternately aligning and overlapping the first substrate and the second substrate while deformation on at least one of the first substrate and the second substrate caused by the operating force is maintained. In the substrate overlapping device, the operating force control unit may make the operating force act on a partial region on the first substrate. Also, the substrate overlapping device includes a calculation unit for making a plurality of alignment indexes provided on the first substrate and a plurality of alignment indexes provided on the second substrate calculate a target position of overlapping where the amount of positional misalignment of the respective indexes to a reference position is minimized when the first substrate overlaps with the second substrate. The operating force control unit may decide the partial region based on a result calculated by the calculation unit.

Description

  The present invention relates to a substrate overlaying apparatus, a substrate holder, a substrate overlaying system, a substrate overlaying method, and a device manufacturing method.

Patent Document 1 describes that an alignment mark is provided on each of a pair of substrates to be stacked, and the pair of substrates is aligned using the mutual alignment mark as an index.
[Prior art documents]
[Patent Literature]
[Patent Document 1] US Pat. No. 6,214,692 specification

  Even if the pair of substrates are relatively moved in any direction including rotation in order to align the alignment marks, some alignment marks may not be aligned. In addition, the alignment may take a long time.

  Accordingly, in order to solve the above-described problem, as a first aspect of the present invention, an acting force control unit that applies acting force to at least one of the first substrate and the second substrate, and the first substrate and the first substrate by the acting force. There is provided a substrate superimposing apparatus including an overlapping unit that aligns and superimposes the first substrate and the second substrate while maintaining deformation generated in at least one of the two substrates.

  Further, as a second aspect of the present invention, a holding surface that sucks and holds the substrate, a plurality of suction portions that are provided corresponding to the holding surface divided into a plurality of regions, and a plurality of suction portions There is provided a substrate holder provided with a plurality of acting force generating portions that are provided corresponding to the holding surfaces divided into the regions, and extend and contract in the surface direction of the substrate.

  Furthermore, as a third aspect of the present invention, a first substrate holder that sucks and holds the first substrate, a second substrate holder that sucks and holds the second substrate facing the first substrate, and the first substrate An acting force control unit configured to deform at least one of the first substrate and the second substrate by controlling an acting force generation unit provided on at least one of the substrate holder and the second substrate holder; and the first substrate holder And a substrate superposition system provided with a superposition part which superposes and aligns mutually, maintaining the above-mentioned deformation by controlling the adsorption part provided in at least one of the second substrate holders is provided.

  Furthermore, as a fourth aspect of the present invention, an action force generating step for causing deformation by causing an action force to act on at least one of the first substrate and the second substrate; and maintaining the deformation, the first substrate and the second substrate There is provided a substrate superimposing method including a superimposing step of aligning and superimposing second substrates on each other.

  Furthermore, as a fifth aspect of the present invention, there is provided a device manufacturing method manufactured by superimposing a first substrate and a second substrate, wherein the step of superimposing the first substrate and the second substrate comprises: An acting force generating step of causing an acting force to act on at least one of the substrate and the second substrate to cause a deformation in the surface direction of the substrate; and maintaining the deformation, the first substrate and the second substrate are mutually connected A device manufacturing method including a superimposing step of aligning and superimposing on a device is provided.

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

1 is a plan view of a bonding apparatus 100. FIG. It is the perspective view which looked down at the substrate holder 220. FIG. It is the perspective view which looked up at the substrate holder 220. FIG. 4 is a longitudinal sectional view of an aligner 160. FIG. 4 is a longitudinal sectional view of an aligner 160. FIG. 4 is a longitudinal sectional view of an aligner 160. FIG. It is a longitudinal cross-sectional view of the pressurizer 130. It is sectional drawing which shows the state transition of the board | substrate 210. FIG. It is sectional drawing which shows the state transition of the board | substrate 210. FIG. It is sectional drawing which shows the state transition of the board | substrate 210. FIG. It is sectional drawing which shows the state transition of the board | substrate 210. FIG. It is a figure explaining the alignment method by the alignment mark 216. FIG. 5 is a flowchart showing a procedure for alignment in an aligner 160. 4 is a flowchart showing a procedure for alignment in the pressurizing device 130; FIG. 4 is a partially enlarged view of a pressurizing device 130. It is a flowchart which shows the procedure of alignment. 3 is a graph showing a temperature change of a substrate 210. It is a perspective view which shows the form of the board | substrate 210. FIG. 5 is a cross-sectional view showing a structure of a substrate holder 220. FIG. 6 is a cross-sectional view illustrating the operation of the substrate holder 220. FIG. 6 is a cross-sectional view illustrating the operation of the substrate holder 220. FIG. 6 is a cross-sectional view illustrating the operation of the substrate holder 220. FIG. 5 is a perspective view showing functions of a substrate holder 220. FIG. 5 is a cross-sectional view showing a structure of a substrate holder 220. FIG. 5 is a perspective view showing functions of a substrate holder 220. FIG. 6 is a cross-sectional view illustrating the operation of the substrate holder 220. FIG. 6 is a cross-sectional view illustrating the operation of the substrate holder 220. FIG. 6 is a cross-sectional view illustrating the operation of the substrate holder 220. FIG. 6 is a cross-sectional view illustrating the operation of the substrate holder 220. FIG. 6 is a cross-sectional view illustrating the operation of the substrate holder 220. FIG. 5 is a cross-sectional view showing a structure of a substrate holder 220. FIG. 5 is a perspective view showing functions of a substrate holder 220. FIG.

  Hereinafter, the present invention will be described through embodiments of the invention. The following embodiments do not limit the invention according to the claims. Not all combinations of features described in the embodiments are essential for the solution of the invention.

[Example 1]
FIG. 1 is a plan view schematically showing the overall structure of the bonding apparatus 100. The joining apparatus 100 includes a housing 110, a loader 120 accommodated in the housing 110, a pressurizing device 130, a holder stocker 140, a pre-aligner 150, and an aligner 160. A plurality of FOUPs (Front Opening Unified Pods) 101 are mounted on the outer surface of the housing 110.

  The FOUP 201 accommodates a plurality of substrates 210 and can be detached from the housing 110 individually. By using the FOUP 201, a plurality of substrates 210 can be loaded into the bonding apparatus 100 at once. In addition, the laminated substrate 212 manufactured by bonding the substrates 210 can be collected in the FOUP 201 and carried out collectively.

  Note that the substrate 210 here may be a glass substrate or the like in addition to a semiconductor substrate such as a silicon single crystal substrate or a compound semiconductor substrate. Further, the substrate 210 used for bonding may include a plurality of elements. Furthermore, the substrate 210 itself to be bonded may be a stacked substrate 212 that has already been stacked and bonded.

  The housing 110 hermetically surrounds the loader 120, the pressurizing device 130, the holder stocker 140, the pre-aligner 150, and the aligner 160. Thereby, the passage route of the substrate 210 in the bonding apparatus 100 is maintained in a clean environment. Note that the substrate 210 may be handled in an inert atmosphere by replacing the air in the housing 110 with a purge gas such as nitrogen. In some cases, the substrate 210 is handled in a vacuum environment by exhausting the inside of the housing 110 or a part thereof.

  The loader 120 includes a fork 122, a fall prevention claw 124, and a folding arm 126. One end of the folding arm 126 is rotatably supported with respect to the housing 110. The other end of the folding arm 126 supports the fork 122 and the fall prevention claw 124 so as to be rotatable about a vertical axis and a horizontal axis.

  The fork 122 sucks and holds the mounted substrate 210 or substrate holder 220. Thereby, the loader 120 moves the substrate 210 or the substrate holder 220 held by the fork 122 to an arbitrary position by combining bending and rotation of the loader 120 itself.

  The fall prevention claw 124 is inserted below the fork 122 when the fork 122 is inverted and holds the substrate 210 or the substrate holder 220 on the lower side. As a result, the substrate 210 or the substrate holder 220 is prevented from falling to the floor in the housing 110. When the fork 122 does not reverse, the fall prevention claw 124 retracts to a position where it does not interfere with the substrate 210 and the substrate holder 220 on the fork 122.

  Such a loader 120 can transport the substrate 210 and the substrate holder 220 from the FOUP 201 to the pre-aligner 150, from the pre-aligner 150 to the aligner 160, and from the aligner 160 to the pressure device 130. Further, the loader 120 conveys the laminated substrate 212 to which the substrate 210 is bonded to the FOUP 201.

  The holder stocker 140 accommodates and waits for the substrate holder 220 that holds the substrate 210. The substrate holders 220 are taken out one by one by the loader 120, and each holds the substrates 210 one by one. The substrate holder 220 holding the substrate 210 is handled integrally with the substrate 210 inside the bonding apparatus 100. Thereby, the thin and fragile substrate 210 is protected, and the handling of the substrate 210 inside the bonding apparatus 100 is facilitated.

  The substrate holder 220 is separated from the multilayer substrate 212 and returned to the holder stocker 140 when the multilayer substrate 212 is unloaded from the bonding apparatus 100. Thereby, the substrate holder 220 is not taken out of the bonding apparatus 100 at least during the period when the bonding apparatus 100 is operating.

  The pre-aligner 150 has an alignment mechanism in which processing speed is more important than alignment accuracy. For example, the pre-aligner 150 adjusts the variation in the mounting position of the substrate 210 or the substrate holder 220 with respect to the loader 120 so as to be within a predetermined range. This shortens the time required for alignment in the aligner 160 described later.

  Depending on the specifications of the bonding apparatus 100, the pre-aligner 150 may hold the substrate 210 in alignment with the substrate holder 220 and further mount the substrate holder 220 holding the substrate 210 on the loader 120. In the pre-aligner 150, the substrate 210 and the substrate holder 220 may be exclusively aligned with the loader 120, and the substrate 210 may be held on the substrate holder 220 at other locations such as the aligner 160.

  Furthermore, the pre-aligner 150 may also include a rotation correction unit that aligns the orientation direction of the substrate 210 with a certain direction with respect to the loader 120. Thereby, the adjustment amount in the aligner 160 described later is reduced, and the work time in the aligner 160 is shortened.

  The aligner 160 superposes the pair of substrates 210 held by the substrate holder 220 after aligning each other. The alignment accuracy required for the aligner 160 is high. For example, when aligning a semiconductor substrate on which an element is formed, submicron level accuracy is required. The structure and operation of the aligner 160 will be described later.

  The pressurizing device 130 pressurizes the pair of substrates 210 that are aligned and overlapped in the aligner 160 and bonds the substrates 210 to each other. As a result, the substrate 210 becomes a laminated substrate 212 that is permanently laminated. The structure and operation of the pressure device 130 will be described later.

  FIG. 2 is a perspective view of the substrate holder 220 as viewed from obliquely above. The substrate holder 220 has a holding surface 222, a flange portion 224, and a through hole 226.

  The substrate holder 220 is formed in a disc shape as a whole and has a flat holding surface 222 for holding the substrate 210 at the center. The flange portion 224 is disposed adjacent to the holding surface 222 and around the holding surface 222. A step 223 is formed between the holding surface 222 and the flange portion 224, and the holding surface 222 slightly protrudes with respect to the flange portion 224.

  The through hole 226 is provided for the purpose of inserting the push-up pin, and may be omitted in the substrate holder 220 used in the bonding apparatus 100 that does not use the push-up pin. When the through holes 226 are provided, three or more are provided in the flange portion 224 while avoiding the holding surface 222. A groove 221 that makes a round around the substrate holder 220 is formed on the side peripheral surface of the flange portion 224. The use of the groove 221 will be described later.

  FIG. 3 is a perspective view of the substrate holder 220 as viewed from below. A through hole 226 and a power supply contact 228 are disposed on the lower surface of the substrate holder 220. Moreover, the groove | channel 221 distribute | arranged to the side peripheral surface of the flange part 224 can also be seen.

  The power supply contact 228 forms a common surface with the lower surface of the substrate holder 220 and is connected to an internal electrode embedded in the substrate holder 220. Thus, the substrate 210 can be electrostatically adsorbed and held on the holding surface 222 by applying a voltage to the internal electrode via the power supply contact 228.

  A plurality of internal electrodes may be provided on one substrate holder 220, and a plurality of power supply contacts 228 may also be provided corresponding to the internal electrodes. Further, a part of the power supply contact 228 may be used for signal transmission. Further, the substrate holder 220 is integrally formed of a highly rigid material such as ceramics or metal, but is insulated from at least the power contact 228.

  FIG. 4 is a schematic longitudinal sectional view showing the structure and operation of the aligner 160 alone. The aligner 160 includes a frame body 162, a drive unit 180, a lower stage 170, and an upper stage 190 disposed inside the frame body 162.

  The frame body 162 includes a bottom plate 161 and a top plate 165 that are horizontal and parallel to each other, and a plurality of support columns 163 that couple the bottom plate 161 and the top plate 165. The bottom plate 161, the support column 163, and the top plate 165 are each formed of a highly rigid material, and the frame body 162 is not deformed even when a reaction force due to the operation of the aligner 160 is applied.

  The upper stage 190 and the microscope 191 are suspended from the lower surface of the top plate 165 of the frame body 162. The upper stage 190 and the microscope 191 are fixed with respect to the top plate 165 and do not move.

  However, a plurality of load cells 197 are sandwiched between the upper stage 190 and the top plate 165. Thereby, when the upper stage 190 or the substrate 210 held thereon is pushed up, the load applied to the substrate 210 can be detected.

  Further, the upper stage 190 has a reflecting mirror 198. The reflecting mirror 198 is fixed with respect to the upper stage 190 and reflects light emitted from an interferometer (not shown). Thereby, the interferometer can detect the position of another measurement object on the basis of the absolute position of the upper stage 190.

  Furthermore, the upper stage 190 has a heat source 193 on its lower surface. The heat source 193 generates or absorbs heat to heat or cool the mounted substrate holder 220 and the substrate 210. A heat insulating material 195 is sandwiched between the heat source 193 and the upper stage 190 so that the thermal influence from the heat source 193 does not reach the upper stage 190 itself.

  As the heat source 193, any one that generates and absorbs heat such as a Peltier effect element, and one that exclusively heats such as a resistance heater or an induction heater can be used. In addition, it is possible to use a device for adjusting the temperature by circulating a heat medium or a refrigerant supplied from the outside. This type of instrument can be used for both heating and cooling by changing the circulating medium or adjusting the temperature.

  The upper stage 190 has a downward mounting surface, and holds the substrate holder 220 holding the substrate 210 via the heat source 193 by an adsorption mechanism such as vacuum adsorption or electrostatic adsorption. Thereby, the temperature of the substrate 210 held on the upper stage 190 can be controlled by the heat source 193. Further, the substrate 210 held on the upper stage 190 faces the substrate 210 held on the lower stage 170 described later.

  A lower stage 170 mounted on the drive unit 180 is placed on the upper surface of the bottom plate 161 of the frame body 162. The driving unit 180 includes an X-direction driving unit 184 and a Y-direction driving unit 186 that are stacked on the bottom plate 161.

  The X-direction drive unit 184 moves in the X direction shown in the drawing while being guided by a guide rail 182 fixed on the bottom plate 161. The Y direction driving unit 186 moves in the Y direction orthogonal to the X direction while being transported in the X direction by the X direction driving unit 184. The Y direction driving unit 186 supports the support plate 172 that supports the lower stage 170.

  Further, the support plate 172 supports the lower stage 170 via the vertical drive unit 177 and the spherical seat 176. Between the support plate 172 and the vicinity of the peripheral edge of the lower stage 170, a plurality of swing drive units 174 are disposed. The swing drive unit 174 individually expands and contracts to raise or lower the lower stage 170. As a result, the lower stage 170 swings on the support plate 172 with the spherical seat 176 as the swing axis.

  The vertical driving unit 177 raises or lowers the lower stage 170 vertically. When the vertical drive unit 177 moves the lower stage 170 up and down, the lower stage 170 moves up or down while maintaining the inclination set by the swing drive unit 174.

  The mounting surface of the lower stage 170 has a suction mechanism by, for example, vacuum suction, electrostatic suction or the like, and holds and holds the mounted substrate holder 220 via a heat source 173 or the like. This prevents the mounted substrate holder 220 from being displaced on the lower stage 170.

  Therefore, by combining the operations of the X direction driving unit 184 and the Y direction driving unit 186, the substrate 210 held on the lower stage 170 can be horizontally moved in an arbitrary direction. Further, by operating the swing driving unit 174, the inclination of the substrate 210 held on the lower stage 170 can be changed.

  Furthermore, the lower stage 170 is raised by operating the vertical driving unit 177, and the substrate 210 held on the lower stage 170 can be bonded to the substrate 210 held on the upper stage 190. However, since the pressure applied to the substrate 210 by the aligner 160 is smaller than that of the pressurizing device 130 described later, it is not possible to maintain the temporary bonding of the substrate 210 permanently.

  Although not shown, the aligner 160 also includes a rotation drive unit. The rotation driving unit rotates the lower stage 170 around a vertical axis orthogonal to the bottom plate 161. Thus, the aligner 160 can also rotate the substrate 210 held on the lower stage 170 about the vertical axis.

  The lower stage 170 includes a microscope 171, a heat source 173, and a reflecting mirror 178. The microscope 171 and the reflecting mirror 178 are fixed with respect to the lower stage 170 and displaced together with the lower stage 170. The microscope 171 is used when the relative position between the substrate 210 and the lower stage 170 is detected by observing the alignment mark 216 of the substrate 210 held on the upper stage 190.

  The reflecting mirror 178 is used when measuring the absolute position of the lower stage 170 by reflecting light emitted from an interferometer (not shown). The reflecting mirror 178 is used when detecting the amount of movement when the lower stage 170 moves.

  The heat source 173 generates or absorbs heat, and heats or cools the substrate 210 via the mounted substrate holder 220. A heat insulating material 175 is sandwiched between the heat source 173 and the lower stage 170 so that the thermal influence of the heat source 173 does not reach the lower stage 170 itself.

  As the heat source 173, any one that generates and absorbs heat such as a Peltier effect element, and one that exclusively heats such as a resistance heater or an induction heater can be used. In addition, it is possible to use a device for adjusting the temperature by circulating a heat medium or a refrigerant supplied from the outside. This type of instrument can be used for both heating and cooling by changing the circulating medium or adjusting the temperature.

  The aligner 160 as described above operates under the control of the control unit 167. That is, as will be described later, the control unit 167 detects a positional shift between the pair of substrates 210 mounted on the lower stage 170 and the upper stage 190, and operates each unit of the aligner 160 to eliminate the positional shift. The control unit 167 controls the entire bonding apparatus 100.

  FIG. 5 is a diagram for explaining the operation of the aligner 160. First, the X direction driving unit 184 and the Y direction driving unit 186 are operated so that the pair of substrates 210 held by the lower stage 170 and the upper stage 190 are substantially opposed to each other. In this state, the swing drive unit 174 is individually operated while observing from the side with a camera or the like (not shown), and the opposing surfaces of the pair of substrates 210 held by the lower stage 170 and the upper stage 190 are parallel. Can be.

  Further, the X direction driving unit 184 and the Y direction driving unit 186 are operated to observe the alignment mark 216 of the substrate 210 held on the lower stage 170 in the field of view of the upper microscope 191. Thereby, the relative position with respect to the upper stage 190 of the substrate 210 can be measured. Similarly, the alignment mark 216 of the substrate 210 held on the upper stage 190 is observed with the microscope 171 of the lower stage 170, and the relative position between the substrate 210 and the lower stage 170 is measured.

  Based on these measurements, it is possible to detect the horizontal relative displacement amount of the pair of substrates 210. Therefore, it is possible to align the positions of the pair of substrates 210 by calculating a so-called alignment amount that eliminates the detected misregistration and moving the lower stage 170 according to the calculated alignment amount. .

  Furthermore, the lower stage 170 and the upper stage 190 have heat sources 173 and 193, respectively. Therefore, the held substrate 210 and the substrate holder 220 can be individually heated or cooled to generate a temperature difference between the pair of substrates 210.

  The substrate 210 in which the temperature difference occurs causes thermal expansion or contraction according to the respective temperatures. Therefore, in the substrate 210 having a higher temperature, the interval between the plurality of alignment marks 216 is widened.

  From the viewpoint of causing a temperature difference, it is sufficient that either one of the lower stage 170 and the upper stage 190 has a heating device or a cooling device. However, by providing the heat sources 173 and 193 on both sides, it becomes easy to generate an accurate temperature difference without being affected by the ambient temperature.

  In many cases, since the substrate 210 is overwhelmingly thinner than the substrate holder 220, the difference in heat capacity between the two is remarkably large. Therefore, the temperature of the substrate 210 can be substantially managed by managing the temperature of the substrate holder 220.

  FIG. 6 is a diagram illustrating another operation of the aligner 160. As described above, the pair of substrates 210 that are parallel to each other and that have been displaced in the horizontal direction can be temporarily joined by raising the lower stage 170 so that one of the substrates is brought into contact with the other. In the pair of temporarily bonded substrates 210, a plurality of pads formed on each surface of the substrate 210 are coupled to each other, and an integrated circuit is formed through both the pair of substrates 210. In addition, when joining a pair of board | substrate 210, it is preferable to monitor the detection value of the load cell 197, and to manage so that an excessive load may not be applied to the board | substrate 210. FIG.

  As described above, in the aligner 160, the lower stage 170 and the upper stage 190 include the heat sources 173 and 193, respectively. Therefore, the pair of substrates 210 can be joined by bringing the lower stage 170 closer to the upper stage 190 while the pair of substrates 210 are individually heated or cooled to generate a temperature difference.

  FIG. 7 is a schematic longitudinal sectional view of the pressurizing device 130. The pressurizing device 130 includes a surface plate 138 and a heating plate 136 that are sequentially stacked from the bottom of the housing 132, and an indented portion 134 and a heating plate 136 that are suspended from the ceiling surface of the housing 132. Each of the heating plates 136 includes a heater. An inlet 131 is provided on one of the side surfaces of the housing 132.

  The substrate 210 that has already been aligned and superimposed is carried into the pressure device 130 together with the substrate holder 220 and the substrate holder 220. The loaded substrate 210 and the substrate holder 220 are placed on the upper surface of the heating plate 136 of the surface plate 138.

  The pressurizing device 130 raises the temperature of the heating plate 136 and lowers the indented portion 134 to push down the upper heating plate 136. As a result, the substrate 210, the substrate holder 220, and the substrate holder 220 sandwiched between the heating plates 136 are heated and pressed, and the substrate 210 is in a permanently bonded state.

  Further, the heating temperature of the heating plate 136 is individually set under the control of the control unit 167. Thereby, a temperature difference can be generated between the pair of substrate holders 220 and the substrate 210.

  Although not shown, a cooling unit that cools the substrate 210 after heating and pressurization may be provided in the pressurizer 130. Thereby, even if it does not reach room temperature, the board | substrate 210 cooled to some extent can be carried out and it can return to FOUP201 rapidly.

  When the heating temperature by the heating plate 136 is high, the surface of the substrate 210 may react scientifically with the atmosphere. Therefore, when the substrate 210 is heated and pressurized, the inside of the housing 132 is preferably evacuated to a vacuum environment. Therefore, an openable / closable shutter that closes the loading port 131 in an airtight manner may be provided. On the other hand, the heating plate 136 may be omitted, and the mirror-polished substrate 210 may be bonded at room temperature.

  8, 9, 10 and 11 are diagrams showing the transition of the state of the substrate 210 in the bonding apparatus 100. FIG. Hereinafter, the operation of the bonding apparatus 100 will be described with reference to these drawings.

  The substrate 210 to be bonded is loaded into the bonding apparatus 100 while being accommodated in the FOUP 201. In the bonding apparatus 100, first, the loader 120 places the substrate holder 220 carried out from the holder stocker 140 on the pre-aligner 150.

  In the pre-aligner 150, the mounting position of the substrate holder 220 with respect to the loader 120 is adjusted. As a result, the loader 120 can carry the substrate holder 220 into the aligner 160 with relatively high accuracy.

  Next, the loader 120 conveys the substrates 210 carried out one by one from the FOUP 201 to the pre-aligner 150. In the pre-aligner 150, the mounting position of the substrate 210 with respect to the loader 120 is also adjusted. Thereby, the loader 120 can mount the substrate 210 on the substrate holder 220 in the aligner 160 with relatively high accuracy.

  The substrate 210 placed on the substrate holder 220 is held on the substrate holder 220 by electrostatic adsorption or the like. Since they are mounted on the upper stage 190 and the lower stage 170, at least two substrate holders 220 holding the substrate 210 are prepared.

  Thus, as shown in FIG. 8, a substrate holder 220 holding the substrate 210 is prepared. In the following steps, the substrate 210 and the substrate holder 220 are handled integrally.

  The loader 120 sequentially transports the substrate holder 220 holding the substrate 210 to the aligner 160. For example, the substrate holder 220 transported first is reversed by the loader 120 and held on the upper stage 190. Further, the substrate holder 220 loaded next is held on the lower stage 170 in the same direction. As shown in FIG. 9, the substrates 210 held by these substrate holders 220 are temporarily joined in alignment with each other.

  Here, since the pair of substrates 210 temporarily joined in the aligner 160 has not yet been joined, the clip 230 is fitted into the groove 221 of the substrate holder 220 as shown in FIG. Thus, the pair of substrate holders 220 sandwiching the aligned substrate 210 can be integrally transported while maintaining the alignment by the aligner 160.

  Subsequently, the loader 120 conveys the substrate holder 220 sandwiching the pair of temporarily bonded substrates 210 to the pressure device 130. The pair of substrates 210 heated and pressurized in the pressurizing apparatus 130 are finally bonded to form a permanent laminated substrate 212 as shown in FIG.

  Further, the loader 120 separates the substrate holder 220 and the laminated substrate 212. The substrate holder 220 is transported to the holder stocker 140. In addition, the laminated substrate 212 is collected in the FOUP 201.

  FIG. 12 is a diagram schematically showing the state of the surface of the substrate 210 aligned as described above. The substrate 210 has a circular shape partially cut away by the notch 214, and has a plurality of alignment marks 216 and element regions 218 on the surface.

  The notch 214 is formed corresponding to the crystal orientation of the substrate 210 and the like. Therefore, when the substrate 210 is handled, the direction of the substrate 210 can be known using the notch 214 as an index. In the element region 218, an element formed by processing the substrate 210 is disposed.

  A plurality of element regions 218 are disposed on the substrate 210. The element region 218 has some connection terminal and is electrically coupled to the element region 218 of another substrate 210 to be bonded.

  The alignment mark 216 is formed together with the element region 218 when the element region 218 is formed on the substrate 210. For this reason, by aligning the alignment mark 216, the element region 218 can also be aligned.

  Note that although the element regions 218 and the alignment marks 216 are drawn large in the drawing, the number of element regions 218 formed on the large substrate 210 of 300 mmφ may reach several hundreds or more. Accordingly, the number of alignment marks 216 arranged on one substrate 210 increases.

  The cross-shaped alignment mark 216 shown in the drawing is merely an example, and the alignment mark 216 is formed in various shapes. Furthermore, a wiring pattern or the like formed in the element region 218 or its periphery may be used as the alignment mark 216.

  FIG. 13 is a flowchart showing a procedure for aligning the substrate 210 in the aligner 160. The pair of substrates 210 is carried into the aligner 160 while being held by the substrate holder 220.

  The loaded substrate 210 and substrate holder 220 are first held on the lower stage 170 and the upper stage 190, respectively, as shown in FIG. 4, and are further aligned with each other as shown in FIG. It starts (step S101).

  The substrate 210 is held by the substrate holder 220 by, for example, electrostatic adsorption. Further, the substrate holder 220 is held by the upper stage 190 and the lower stage 170, for example, by vacuum suction. However, the present invention is not limited to these methods, and the substrate 210, the substrate holder 220, and the upper stage 190 or the lower stage 170 are integrated with each other, and are fixed by a method that does not cause misalignment in the following alignment operation.

  Next, the swing drive unit 174 is operated to make the substrate 210 held on the upper stage 190 and the substrate 210 held on the lower stage parallel to each other (step S102). The following alignment operation is continued while the parallelism of the pair of substrates 210 is maintained.

  Subsequently, the alignment marks 216 on the opposing substrates 210 are observed with the microscopes 171 and 191, respectively. Thereby, for example, the positions of a plurality of alignment marks 216 to be aligned are measured with reference to the position of the fixed microscope 191 (step S103).

  Further, by measuring the position of the alignment mark 216 with respect to each of the substrates 210, a positional deviation amount between the pair of substrates 210 is detected (step S104). Next, the control unit 167 causes the calculation unit 169 to calculate an alignment amount that eliminates the positional deviation (step S105). Here, the alignment amount calculated by the calculation unit 169 includes movement amounts δx and δy, a rotation amount θ, and a magnification γ given to the substrate 210 so as to make the positional deviation amount zero.

  The movement amounts δx and δy are given to the substrate 210 held on the lower stage 170 by the X direction driving unit 184 and the Y direction driving unit 186. The rotation amount θ is given to the substrate 210 held on the lower stage 170 by the rotation driving unit. The magnification γ can be given as a temperature difference generated between the pair of substrates 210 held by the lower stage 170 and the upper stage 190 by the heat sources 173 and 193.

  That is, even if the lower stage 170 is translated and rotated so that the amount of positional deviation is statistically minimized, in many cases, many of the alignment marks 216 of the pair of substrates 210 may not coincide with each other. This is considered to be caused by variation in the reduction ratio of the pattern transferred to the alignment mark 216 and the element region 218 in the process of forming the alignment mark 216 and the element region 218.

Therefore, an element of the magnification γ of the alignment mark 216 is introduced as an element for calculating the alignment amount by the calculation unit 169. The relationship between the elements of the alignment amount including the magnification γ can be expressed by the following formula 1.

  The calculation unit 169 calculates an enlargement rate or reduction rate for one of the other so that the difference in the magnification γ of the pair of substrates 210 is statistically minimized. Further, a target temperature difference required for enlarging or reducing the substrate at such an enlargement rate or reduction rate is calculated. The calculation unit 169 uses the heat sources 173 and 193 to compare the statistics of misregistration caused by a certain temporary target temperature difference with the statistics of misregistration caused by other temporary target temperature differences, and obtain more accurate accuracy. A high target temperature difference can also be calculated.

  In the above embodiment, the heat source 173, 193 is provided in the aligner 160 to calculate the magnification λ as the alignment amount. However, the alignment amount is calculated from the position of the alignment mark 216 measured in step 103. The magnification γ can also be calculated. In that case, the heat sources 173 and 193 of the aligner 160 can be omitted.

  When the alignment amount including the target temperature difference is calculated in this way, the control unit 167 first moves the lower stage 170 by the movement amounts δx and δy (step S106). Next, the control unit 167 rotates the lower stage 170 by the rotation amount θ (step S107).

  Thus, the control unit 167 operates the vertical drive unit 177 to raise the substrate 210 held on the lower stage 170. As a result, the pair of substrates 210 aligned by translation and rotation are temporarily joined (step S108). The pair of temporarily bonded substrates 210 is stored in an aligned state by fitting the clip 230 to the substrate holder 220 (step S109).

  In this way, the pair of substrates 210 in which the aligned state is preserved by translation and rotation is unloaded from the aligner 160 by the loader 120 (step S110). The pair of substrates 210 carried out from the aligner 160 is carried by the loader 120 and carried into the pressurizing device 130.

  FIG. 14 is a flowchart showing an operation procedure of the pressurizing apparatus 130 into which the pair of substrates 210 is carried. The pressure device 130 loaded with the temporarily bonded substrate 210 first lowers the indented portion 134 to fix the pair of substrates 210 and the substrate holder 220 (step S201). However, the pressure applied to the substrate 210 at this time is limited to a pressure sufficient to fix the substrate 210. Therefore, the substrate 210 is not yet fully bonded.

  Next, in a state where the substrate 210 is fixed, the control unit 167 sets individual temperatures for the heating plates 136, and causes the pair of substrates 210 to generate the target temperature difference calculated by the calculation unit 169 (step S202). Thereby, different thermal expansion occurs in the pair of substrates 210 according to the target temperature difference, and the positional deviation due to the difference in the magnification γ remaining in the pair of substrates 210 is eliminated.

  In this way, the pressurizing device 130 applies a high pressure to the substrate 210 and finally bonds the substrate 210 to the substrate 210 from which the displacement due to translation, rotation, and magnification has been eliminated (step S203). In addition, the control unit 167 significantly increases the temperature of the heating plate 136, and finally bonds the substrate 210 in a state where the positional deviation is eliminated.

  FIG. 15 is an enlarged view showing a part of the pressure device 130. In addition, the same reference number is attached | subjected to the same element as FIG. 7, and the overlapping description is abbreviate | omitted.

  While the surface of the heating plate 136 on the surface plate 138 is flat, the lower surface of the heating plate 136 held by the indented portion 134 forms a spherical surface whose center is raised downward. As a result, when the indented portion 134 moves down and presses the upper surface of the substrate holder 220, the substrate holder 220 and the substrate 210 are strongly pressed in the center.

  Thereby, the center of the substrate 210 and the substrate holder 220 is strongly pressed and fixed to the heating plate 136. Further, when a temperature difference occurs, the peripheral portions of the substrate 210 and the substrate holder 220 expand radially. Therefore, when the calculation unit 169 calculates the alignment amount by the magnification γ, the target temperature difference can be calculated with higher accuracy by using the center of the substrate 210 as a reference.

  In the above example, the substrate 210 is handled integrally with the substrate holder 220 consistently. However, it goes without saying that alignment can be performed by a temperature difference even in a bonding apparatus that directly handles the substrate 210 without using the substrate holder 220.

[Example 2]
FIG. 16 is a flowchart showing a procedure for aligning the substrate 210 in the aligner 160. The pair of substrates 210 is carried into the aligner 160 while being held by the substrate holder 220.

  The loaded substrate 210 and substrate holder 220 are first held on the lower stage 170 and the upper stage 190, respectively, as shown in FIG. 4, and are further aligned with each other as shown in FIG. Start (step S301).

  The substrate 210 is held by the substrate holder 220 by, for example, electrostatic adsorption. Further, the substrate holder 220 is held by the upper stage 190 and the lower stage 170, for example, by vacuum suction. However, the present invention is not limited to these methods, and the substrate 210, the substrate holder 220, and the upper stage 190 or the lower stage 170 are integrated with each other, and are fixed by a method that does not cause misalignment in the following alignment operation.

  Next, the control unit 167 operates the swing driving unit 174 to make the substrate 210 held on the upper stage 190 and the substrate 210 held on the lower stage 170 parallel to each other (step S302). The following alignment operation is continued while the parallelism of the pair of substrates 210 is maintained.

  Subsequently, the control unit 167 observes the alignment marks 216 on the opposing substrates 210 with the microscopes 171 and 191, respectively. Thereby, for example, the positions of a plurality of alignment marks 216 to be aligned can be measured with reference to the position of the fixed microscope 191 (step S303).

  Further, the control unit 167 can detect the amount of misalignment between the pair of substrates 210 by measuring the position of the alignment mark 216 with respect to each of the substrates 210 (step S304). Next, the control unit 167 checks whether or not the detected positional deviation amount is within a predetermined allowable range (step S305).

  When the detected positional deviation amount is within the allowable range (step S305: YES), the control unit 167 translates the lower stage 170 so that the substrate 210 of the lower stage 170 and the substrate of the upper stage 190 face each other. (Step S310). In addition, the control unit 167 rotates the lower step 170 so that the alignment marks 216 between the substrates 210 correspond to each other (step S311).

  Further, the control unit 167 operates the vertical driving unit 177 to raise the lower stage 170. As a result, the pair of substrates 210 are joined in a state where the positional deviation is within the allowable range (step S312). The bonded substrate 210 is stored in an aligned state by fitting the clip 230 to the substrate holder 220 (step S313). Thus, the work in the aligner 160 is completed.

  On the other hand, when the amount of misalignment is not within the allowable range in step S305 (step S305: NO), the control unit 167 causes the calculation unit 169 to calculate an alignment amount for eliminating the misregistration (step S306). Here, the alignment amount calculated by the calculation unit 169 includes movement amounts δx and δy, a rotation amount θ, and a magnification γ given to the substrate 210 so as to make the positional deviation amount zero.

  The movement amounts δx and δy are given to the substrate 210 held on the lower stage 170 by the X direction driving unit 184 and the Y direction driving unit 186. The rotation amount θ is given to the substrate 210 held on the lower stage 170 by the rotation driving unit. The magnification γ is given as a temperature difference generated on the pair of substrates 210 held on the lower stage 170 and the upper stage 190 by the heat sources 173 and 193.

  That is, even if the lower stage 170 is translated and rotated so that the amount of positional deviation is statistically minimized, in many cases, many of the alignment marks 216 of the pair of substrates 210 may not coincide with each other. This is considered to be caused by variation in the reduction ratio of the pattern transferred to the alignment mark 216 and the element region 218 in the process of forming the alignment mark 216 and the element region 218.

Therefore, an element of the magnification γ of the alignment mark 216 is introduced as an element for calculating the alignment amount by the calculation unit 169. The relationship between the elements of the alignment amount including the magnification γ can be expressed by the following formula 1.

  The calculation unit 169 calculates an enlargement rate or reduction rate for one of the other so that the difference in the magnification γ of the pair of substrates 210 is statistically minimized. Further, a target temperature difference required for enlarging or reducing the substrate at such an enlargement rate or reduction rate is calculated.

  When the alignment amount including the target temperature difference is calculated in this way, the control unit 167 first moves the lower stage 170 by the movement amounts δx and δy (step S307). Next, the control unit 167 rotates the lower stage 170 by the rotation amount θ (step S308). Further, the control unit 167 generates a target temperature difference between the pair of substrates 210 by the heat sources 173 and 193 (step S309).

  When a target temperature difference is generated between the pair of substrates 210, it is preferable that the temperature deviation from the temperature target managed by the aligner 160 as a whole is equally allocated to both substrates 210. That is, for example, when a temperature difference of ΔT ° C. is generated in the aligner 160 that manages the temperature environment at room temperature, one substrate 210 is (room temperature−ΔT / 2) ° C. and the other substrate 210 is (room temperature + ΔT / 2) It is preferable that a temperature difference ΔT ° C. is generated by setting the temperature to ° C. Thereby, it is possible to minimize the influence of the aligner 160 on the environmental temperature while generating the temperature difference ΔT ° C. in the substrate 210.

  However, when the heat sources 173 and 193 used are heating devices, a temperature difference is generated exclusively by heating. Therefore, the positional deviation may be corrected by increasing both of the pair of substrates 210 with respect to the management temperature of the aligner 160.

  The position measurement of the alignment mark 216 by the microscopes 171 and 191 is performed again on the pair of substrates 210 aligned as described above (step S303). Further, the positional deviation between the substrates 210 is detected again from the position of the alignment mark 216 measured in step S303 (step S304). It is checked whether or not the positional deviation amount of the pair of substrates 210 thus obtained is within a predetermined allowable range (step S305).

  In this way, the measurement and alignment of the positional deviation are repeated until the positional deviation amount falls within the allowable range, and the pair of substrates 210 (step S305: YES) whose positional deviation amount falls within the allowable range are mutually connected as described above. (Step S312). The bonded substrate 210 is stored in an aligned state by fitting the clip 230 to the substrate holder 220 (step S315).

  In addition, when repeating the cycle of misalignment detection and alignment (steps S303 to S309) as described above, the calculation unit 169 calculates the statistics of misalignment caused by the target temperature difference of a certain cycle and the next cycle. A more accurate target temperature difference can be calculated by comparing with the statistics of the positional deviation caused by the target temperature difference.

  The pair of substrates 210 that have been aligned and stored in their state are carried out of the aligner 160 together with the substrate holder 220. The unloaded substrate 210 and substrate holder 220 are loaded into the pressurizing device 130 and heated and pressurized. Thereby, the aligned substrate 210 is permanently bonded while maintaining its state.

  FIG. 17 is a graph showing a temperature change of the pair of substrates 210 in which a temperature difference is generated. As shown in the figure, when the temperature of the substrate 210 heated by the heat sources 173 and 193 to generate the target temperature difference is unloaded from the aligner 160, the temperature gradually decreases with time.

  When the temperature of the substrate 210 and the substrate holder 220 decreases, the temperature decrease rate is faster when the temperature difference from the ambient temperature is larger. For this reason, the temperature difference between the pair of substrates 210 gradually decreases.

  Therefore, the aligner 160 may generate a temperature difference larger than the target temperature difference so that the temperature difference between the pair of substrates 210 becomes the target temperature difference at the time when the pressure is applied by the pressure device 130. preferable.

  In addition, it is also preferable that the control unit 167 manages the time from when the temperature is controlled by the heat sources 173 and 193 after being unloaded from the aligner 160 to when the pressure is applied by the pressurizing device 130 to be constant. In other words, the control unit 167 monitors the state of the pressurizing device 130 and generates a temperature difference on the substrate 210 after the pressurizing device 130 is ready to carry in the substrate 210 and the substrate holder 220. As a result, it is possible to accurately predict a temperature decrease until the pressure is applied by the pressurizing device 130, and to generate a temperature difference that anticipates it.

  Furthermore, the substrate 210 and the substrate holder 220 conveyed from the aligner 160 to the pressure device 130 may be kept warm so that the set temperature difference is maintained. Further, the temperature difference set in the substrate 210 is maintained until the substrate holder 220 is supplied with electric power or the like until the substrate 210 carried out of the aligner 160 and the substrate holder 220 are pressurized by the pressure device 130. You may continue. As a result, the substrate 210 is pressurized by the pressurizing device 130 in a state having an accurate target temperature difference.

  In the above example, the substrate 210 is handled integrally with the substrate holder 220 consistently. However, it goes without saying that alignment can be performed by a temperature difference even in a bonding apparatus that directly handles the substrate 210 without using the substrate holder 220.

[Example 3]
FIG. 18 is a perspective view showing a state in which a pair of substrates 210 to be superimposed on each other face each other. Elements common to the substrate 210 shown in FIG. 12 are assigned the same reference numerals, and redundant description is omitted.

  In the illustrated example, in the upper substrate 210 having the element region 218 on the lower surface, six alignment marks 2161 to 2166 that are referred to when aligning the entire substrate 210 are arranged on the mutually orthogonal guidelines indicated by the dotted line G. It is arranged. On the other hand, in the lower substrate 210 having the element region 218 on the upper surface, one alignment mark 2161 is closer to the inside of the substrate 210 than the reference position assumed from the other alignment marks 2162 to 2166. In position.

  In the vicinity of the alignment mark 2161 whose position is shifted as described above, the position of the element region 218 is also shifted similarly to the alignment mark 2161. Such misalignment of the alignment mark 2161 occurs, for example, in the process of forming the element region 218 on the substrate 210.

  When the positions of some of the alignment marks 2161 are shifted with respect to the other alignment marks 2162 to 2166, even if the magnification is adjusted by enlarging or reducing one of the substrates 210, the alignment marks 2161 to 2166 coincide with each other. Thus, it is difficult to overlap the pair of substrates 210. Alternatively, the calculation process of the calculation unit 169 requires a lot of time.

  Therefore, the calculation unit 169 first calculates an alignment amount so as to align the remaining alignment marks 2162 to 2166 except for a part of the misaligned alignment marks 2161. Accordingly, the calculation unit 169 can quickly calculate an alignment amount that can align the alignment marks 2162 to 2166 between the substrates 210 with high accuracy.

  Next, the calculation unit 169 calculates the alignment amount of the alignment mark 2161 so that the misaligned alignment mark 2161 is fitted to the alignment marks 2162 to 2166 whose alignment amount has already been calculated. Next, the control unit 167 first corrects the position of the alignment mark 2161 according to the calculation results of the calculation unit 169, and then aligns the substrate 210.

  In the illustrated example, the partial area H indicated by hatching in the drawing is heated, for example, so that the partial area H of the substrate 210 is moved relative to the other to correct the position of the alignment mark 2161. That is, when a partial region H of the substrate 210 is heated, the substrate 210 expands in this region, and the misaligned alignment mark 2161 moves away from the center of the substrate 210. Thereby, the position of the alignment mark 2161 can be matched with the other alignment marks 2161 to 2165. After the position of the alignment mark 2161 is corrected, the alignment of the alignment marks 2161 to 2166 on the other substrate 210 is accurately positioned by aligning the substrates 210 with each other. Can be combined.

  It should be noted that the reference position that is a target when aligning the alignment mark 216 as described above may be the corresponding alignment mark 216 of the substrate 210 that forms a pair in the bonding apparatus 100 as described above. . Alternatively, the position of the alignment mark 216 on the substrate 210 to be adjusted may be aligned with the position of the alignment mark 216 on the virtual substrate 210 ideally manufactured as designed as the reference position.

  In this way, it is possible to achieve both high-precision alignment of the substrate 210 and reduction in processing time required for it. If all the alignment marks 216 on the substrate 210 cannot be completely adjusted even in this manner, the adjustable alignment marks 2161 to 2166 may be adjusted so that a part of the substrate 210 is utilized.

  As a method of partially heating the substrate 210, there is a method of transferring heat by providing a heating element on a member in contact with the substrate 210 such as the substrate holder 220. There is also a method of changing the temperature by blowing hot air or cold air onto the substrate 210. Further, there is a method of irradiating a partial region H of the substrate 210 with heat rays such as infrared rays.

  For example, in the case where the substrate 210 that is a silicon single crystal substrate is irradiated with heat rays, the wavelength of the irradiated heat rays can be efficiently heated by setting the wavelength of the substrate 210 to about 1100 nm to 400 nm where absorption due to direct electron transition occurs. In addition, since the silicon single crystal substrate has an absorption of about 6 μm to 25 μm by the lattice, it can be effectively heated even by heat rays in the infrared region.

[Example 4]
FIG. 19 is a cross-sectional view showing a structure of another substrate holder 2201 having a function of partially heating the substrate 210. Elements common to the substrate holder 2201 shown in FIGS. 2 and 3 are denoted by the same reference numerals, and redundant description is omitted.

  The substrate holder 2201 has a plurality of electrothermal material portions 225 arranged immediately below the holding surface 222. The electrothermal material portion 225 is electrically and thermally separated from each other by the separation portion 229 having insulating properties and heat insulating properties. Each of the electrothermal material portions 225 is coupled to a current source 236 via a separate switch 235. Therefore, when the electrothermal material part 225 is energized by the intermittent connection of the switch 235, the electrothermal material part 225 can be individually heated.

  In addition, each of the electrothermal material portions 225 has an embedded electrode 227. Each embedded electrode 227 is coupled to a voltage source 238 via a separate switch 237. Therefore, the voltage can be individually applied to each of the embedded electrodes 227 by the intermittent operation of the switch 237. In a region where a voltage is applied to the embedded electrode 227, an electrostatic force is generated on the surface of the electrothermal material portion 225. Thereby, an electrostatic chuck that attracts the substrate 210 on the surface of the electrothermal material portion 225 is formed.

  Note that the current source 236 and the voltage source 238 may be disposed outside the substrate holder 2201 to supply current or voltage to the substrate holder 2201 via the power supply contact 228 or the like. The switches 235 and 237 may be arranged inside or outside the substrate holder 2201.

  When the switches 235 and 237 are arranged inside the substrate holder 2201, a control signal for controlling the switches 235 and 237 can be transmitted to the substrate holder 2201 by using a part of the power supply contact 228. Further, the region R can be cooled by arranging a Peltier effect element or the like in the electrothermal material portion 225.

  20 and 21 are partial cross-sectional views for explaining the operation of the substrate holder 2201. Elements that are the same as those in FIG. 19 are given the same reference numerals, and redundant descriptions are omitted.

In the state shown in FIG. 20, six regions R arranged linearly are drawn. Among the six regions, in the two regions R on the left side in the figure, the switch 237 is turned on and a voltage is applied to the embedded electrode 227. As a result, an electrostatic force is generated on the surface of the substrate holder 2201 in the region R including the embedded electrode 227 to which a voltage is applied, and the substrate 210 is attracted to the holding surface 222. Note that the surface of the substrate 210, a pair of alignment marks 216 are spaced apart _{L 0.}

  In the state shown in FIG. 21, following the above state, the switch 235 is turned on in the three central regions R, and resistance heat is generated in the electrothermal material portion 225 in these regions R. Therefore, in these regions R, the temperature of the substrate 210 rises to cause thermal expansion.

As already described, in the region R on the left side in the drawing, the substrate 210 is adsorbed to the substrate holder 2201. Therefore, when the substrate 210 is thermally expanded, the region R on the right side in the figure moves to the right. Therefore, the alignment mark 216 formed in this region also moves to the right, the distance between the pair of alignment marks 216 to expand to L _1.

  In the state shown in FIG. 22, following the above state, the switch 237 is turned on in all the regions R, and the substrate 210 is attracted to the holding surface 222. Further, all the switches 235 are cut off, and the heat generation of the electrothermal material portion 225 is stopped. Therefore, partial thermal expansion of the substrate 210 is also eliminated.

  However, since the substrate 210 is adsorbed over the entire surface by the substrate holder 2201, even if the thermal expansion is eliminated, the position of the alignment mark 216 displaced by the thermal expansion is maintained. Therefore, by continuing the application of the voltage to the buried electrode 227, the position of the alignment mark 216 corrected on the substrate 210 is maintained.

  The adsorption of the substrate 210 by the substrate holder 2201 is continued by the residual voltage for a short time even when the embedded electrode 227 is disconnected from the voltage source 238. Therefore, when the substrate 210 is transported or the like, the corrected position of the alignment mark 216 can be continuously held by handling the substrate 210 together with the substrate holder 2201 while being held by the substrate holder 2201.

  In view of the above applications, the adsorption force of the substrate 210 by the substrate holder 2201 has a strength capable of holding the deformation of the substrate 210 against the restoring force of the substrate 210 from which thermal expansion has been eliminated. In addition, the substrate holder 2201 has a rigidity that does not deform due to the restoring force of the substrate 210.

  The position correction of some of the alignment marks 216 as described above may be combined with enlargement or reduction of the entire substrate 210 described with reference to FIGS. As a result, the substrate 210 can be superimposed with more precise alignment. Furthermore, for the purpose of adjusting the position of the alignment mark 216 exclusively by thermal expansion, both the pair of substrates 210 may be heated while providing a temperature difference.

  FIG. 23 is a perspective view of the substrate holder 2201 described above. As illustrated, the region R occupied by each of the electrothermal material portions 225 is two-dimensionally arranged on the entire holding surface 222. In addition, each of the electrothermal material portions 225 expands or contracts two-dimensionally in individual regions R as indicated by arrows W in the drawing. Therefore, the position of the alignment mark 216 can be corrected in an arbitrary region of the substrate 210 held by the substrate holder 2201.

[Example 5]
FIG. 24 is a cross-sectional view showing another structure of the substrate holder 2202. Elements common to the substrate holder 2202 shown in FIG. 19 are denoted by the same reference numerals, and redundant description is omitted.

  The substrate holder 2202 has a plurality of piezoelectric material portions 234 arranged immediately below the holding surface 222. The piezoelectric material portion 234 is electrically separated by a separation portion 229 having an insulating property.

  Each of the piezoelectric material portions 234 is coupled to a voltage source 239 via a separate switch 235. Therefore, when a voltage is applied to the piezoelectric material part 234 by the intermittent operation of the switch 235, the piezoelectric material part 234 can be individually extended. Each of the piezoelectric material portions 234 is polarized in the surface direction of the substrate holder 2202 and extends in that direction.

  Each of the piezoelectric material portions 234 has an embedded electrode 227. Each embedded electrode 227 is coupled to a voltage source 238 via a separate switch 237. Therefore, the voltage can be individually applied to each of the embedded electrodes 227 by the intermittent operation of the switch 237.

  In each region R where a voltage is applied to the embedded electrode 227, an electrostatic force is generated on the surface of the piezoelectric material portion 234. As a result, an electrostatic chuck that attracts the substrate 210 on the surface of the piezoelectric material portion 234 is formed.

  Note that the voltage sources 238 and 239 may be disposed outside the substrate holder 2202 to supply current or voltage to the substrate holder 2202 via the power supply contact 228 or the like. The switches 235 and 237 may be arranged inside or outside the substrate holder 2202. When the switches 235 and 237 are arranged inside the substrate holder 2202, a control signal for controlling the switches 235 and 237 can be transmitted to the substrate holder 2202 using a part of the power supply contact 228.

  FIG. 25 is a perspective view for explaining the function of the substrate holder 2202. In the substrate holder 2202, the piezoelectric material portions 234 that form the individual regions R are two-dimensionally arranged on the holding surface 222.

  Each of the piezoelectric material portions 234 is polarized in a direction different from that of the other adjacent region R. As a result, any region of the holding surface 222 can be deformed in any direction.

  26 and 27 are partial cross-sectional views for explaining the operation of the substrate holder 2202. Elements common to FIGS. 24 and 25 are denoted by the same reference numerals, and redundant description is omitted. Further, for the purpose of simplifying the explanation, it is assumed that the illustrated piezoelectric material portions 234 are all polarized in the same direction.

A case where the position of the alignment mark 216 on the substrate 210 is corrected using the substrate holder 2202 will be described. First, as shown in FIG. 26, after the substrate 210 is mounted on the substrate holder 2202, the switch 235 on the left side in the figure and the switch in the center in the figure are turned on. As a result, the substrate 210 is adsorbed to the substrate holder 2202 except for the right portion in the figure. On the surface of the substrate 210, a pair of alignment marks 216 are spaced apart _{L 0.}

  Next, two switches 235 at the center in the figure are turned on to apply a voltage to the corresponding piezoelectric material portion 234. As a result, as shown in FIG. 27, the piezoelectric material portion 234 to which a voltage is applied extends horizontally. Since the left side and the center in the figure of the substrate 210 are adsorbed by the substrate holder 2202, the right part of the substrate 210 in the figure moves to the right as the piezoelectric material portion 234 expands.

Thus, one of the alignment marks 216 on the substrate 210 be moved, between the pair of alignment marks 216 extend to distance _{L 1.} The distance L ₁ between the alignment marks 216 is maintained as long as the individual open / close states of the switches 235 and 237 are maintained and the deformation of the substrate 210 is maintained.

  In view of the above function of the substrate holder 2202, the substrate holder 2202 has a holding force capable of deforming the substrate 210 within a range of elastic deformation in accordance with its deformation. In addition, the substrate holder 2202 has a rigidity that does not deform within a range of an acting force that causes elastic deformation of the substrate 210.

  In addition, as described above, during the period in which the substrate 210 is deformed by applying and acting on the piezoelectric material portion 234, adsorption of a part of the substrate 210 is stopped, and the substrate 210 is expanded or contracted. The method of adsorbing the partial area later can be applied to the case where the substrate 210 is adsorbed directly to the lower stage 170 without using the substrate holder 220, for example.

  In this case, while the substrate 210 is deformed by the expansion or contraction of the piezoelectric material portion 234, the adsorption of the substrate 210 by the lower stage 170 is stopped in a region adjacent to the region where the deformation occurs in the substrate 210. Thereby, the substrate 210 is smoothly deformed.

  Further, after the substrate 210 is deformed, the substrate 210 may be sucked in a region where the suction is stopped. Thereby, the deformation generated in the substrate 210 can be maintained on the lower stage 170.

28, 29 and 30 are partial cross-sectional views for explaining another operation of the substrate holder 2202. Here, the substrate holder 2202 is used to correct the distance L ₀ between the alignment marks 216 of the substrate 210 to be narrower than the distance L ₂ . Elements common to those in FIGS. 26 and 27 are denoted by the same reference numerals, and redundant description is omitted.

  First, as shown in FIG. 28, a part of the switch 235 is turned on with all the switches 237 opened. As a result, the piezoelectric material portion 234 at the center in the figure extends horizontally, but the substrate 210 is not attracted to the substrate holder 2202, and therefore no deformation occurs. In other words, it is not necessary to place the substrate 210 on the substrate holder 2202 at this stage.

Next, as shown in FIG. 29, all the switches 237 are turned on with the piezoelectric material portion 234 extended. Thereby, the substrate 210 is adsorbed to the substrate holder 2202 as a whole. In this case, on the substrate 210, a pair of alignment marks 216 are spaced apart _{L 0.}

  Next, as shown in FIG. 30, some of the switches 235 that have been turned on are opened, and voltage application to the piezoelectric material portion 234 is stopped. Thereby, the extended piezoelectric material portion 234 returns to the original width. Since the substrate 210 is attracted to the substrate holder 2202 by the electrostatic force, it is shortened in the surface direction of the substrate holder 2202 along with the restoration of the piezoelectric material portion 234 to the initial state.

Thus, a pair of alignment marks 216 approaches to interval _{L 2.} This state is maintained when the switch 237 is continuously turned on and the substrate holder 2202 continues to suck the substrate 210 against the restoring force of the substrate 210.

  In addition, when the polarity of the applied voltage is reversed, the piezoelectric material portion 234 also deforms to contract itself. Therefore, similarly to the operation shown in FIGS. 26 and 27, the piezoelectric material portion 234 can be contracted in a state where the substrate 210 is attracted to the substrate holder 2202.

  However, many of the oxide-based piezoelectric materials such as PZT (lead zirconate titanate) have a tensile strength lower than the compressive strength. Therefore, by contracting the substrate 210 in the procedure shown in FIGS. 28, 29, and 30, the substrate 210 can be contracted using the extending operation of the piezoelectric material portion 234. For the purpose of opposing the tensile force acting on the piezoelectric material portion 234, the separation portion 229 may also serve as a tensile member.

[Example 6]
FIG. 31 is a cross-sectional view showing another structure of the substrate holder 2203. The substrate holder 2203 includes a piezoelectric material portion 234 and an embedded electrode 227 that are disposed immediately below the holding surface 222.

  The piezoelectric material portion 234 includes a plurality of regions that are electrically separated by the separation portion 229. The single embedded electrode 227 is embedded in the plurality of piezoelectric material portions 234 in common.

  Each region of the piezoelectric material portion 234 is individually coupled to a voltage source 239 via a variable attenuator 233 and a switch 235. The buried electrode 227 is coupled to the voltage source 238 via the switch 237.

  When the switch 235 is turned on and a voltage is applied, the piezoelectric material portion 234 extends in the surface direction of the substrate holder 2203. The amount of expansion changes according to the amount of applied voltage determined by the variable attenuator 233. When the switch 237 is turned on and a voltage is applied to the embedded electrode 227, the embedded electrode 227 generates an electrostatic force on the holding surface 222 of the substrate holder 2203.

  FIG. 32 is a perspective view showing the function of the substrate holder 2203. In the substrate holder 2203, each region of the piezoelectric material portion 234 is separated into sectors by a separation portion 229. In addition, each of the piezoelectric material portions 234 is polarized in the radial direction of the substrate holder 2203. Therefore, when a voltage is applied to each of the piezoelectric material portions 234, the substrate holder 2203 expands the holding surface 222.

  Further, when a voltage is applied to the embedded electrode 227, the holding surface 222 attracts and holds the substrate 210 by the generated electrostatic force. Therefore, the substrate 210 can be expanded and deformed by applying a voltage to all the piezoelectric material portions 234 while the substrate holder 2203 holds the substrate 210.

  Thereby, it is possible to correct the misalignment of the alignment mark due to the magnification difference of the held substrate 210. Further, by applying a voltage only to a part of the piezoelectric material portions 234, the held substrate 210 can be deformed in the surface direction.

  Furthermore, the deformation of the entire substrate 210 shown in FIGS. 31 and 32 may be combined with the partial deformation of the substrate 210 shown in FIGS. 28, 29, and 30. Thereby, misalignment of various alignment marks 216 can be corrected. Further, the processing time required for alignment of the alignment mark 216 can be shortened.

  Note that the deformation of the substrate 210 caused by the substrate holders 220, 2201, 2202, 2203 as described above is a fine deformation that occurs in the range of elastic deformation of the substrate 210, so that the substrate 210 is not destroyed by the deformation. However, when one of the pair of substrates 210 used for superposition is a laminated substrate 212 that already has a laminated structure, the other substrate 210 that does not have a laminated structure is deformed by matching the laminated substrate 212 with the other substrate 210. It is preferable. Thereby, it is possible to prevent the laminated substrate 212 from being peeled off due to deformation or the like.

  In the above example, the case has been described in which the substrate holders 220, 2201, 2202, 2203 having the electrothermal material portion 225, the piezoelectric material portion 234, and the like generate an action force that deforms the substrate 210. However, the generation of the acting force is not limited to the substrate holders 220, 2201, 2202, 2203.

  For example, the electrothermal material portion 225, the piezoelectric material portion 234, and the like may be provided on the lower stage 170 or the upper stage 190 of the aligner 160. Further, the same function may be incorporated in other members such as the pre-aligner 150.

  Furthermore, the electrothermal material part 225 and the piezoelectric material part 234 may be mixed and used properly according to the purpose. For example, the electrothermal material portion 225 may be used for adjusting the magnification of the entire substrate 210, and the piezoelectric material portion 234 may be used for adjusting the position of some of the alignment marks 216.

  Furthermore, the target for adjusting the position of the alignment mark 216 may be a specification assumed when the alignment mark 216 is formed on the substrate 210 instead of the alignment mark 216 of the substrate 210 to be superimposed. . As a result, the step of individually measuring the arrangement of the alignment marks 216 on the overlay target substrate 210 can be omitted, and correction of the alignment marks 216 can be started immediately. Therefore, the throughput of the overlay process can be improved.

  Further, in the bonding apparatus 100, it is not necessary to hold all the substrates 210 using the substrate holders 220, 2201, 2202, and 2203 having the electrothermal material portion 225 or the piezoelectric material portion 234. That is, the substrate 210 may be reloaded on the substrate holders 220, 2201, 2202, 2203 having a function of adjusting the alignment mark 216 only when a large shift is detected in the alignment mark 216 in the pre-aligner 150, the aligner 160, and the like. . Thereby, an inexpensive substrate holder 220 that does not have the electrothermal material portion 225 or the piezoelectric material portion 234 can be used for many substrates 210, and the cost of the substrate holder 220 that tends to be high in cost can be suppressed.

  In the first and second embodiments described above, of the pair of substrates 210 to be bonded, the alignment mark 216 of one substrate 210 is used as a reference position, and the alignment mark 216 of the other substrate 210 is aligned therewith. . However, for example, the position of the alignment mark 216 on the virtual substrate 210 ideally manufactured as designed may be used as the reference position, and the position of the alignment mark 216 on the substrate 210 to be adjusted may be individually adjusted to the reference position. Good.

  In the first and second embodiments described above, the example in which the substrate holder 220 is heated and expanded in a state where the substrate holder 220 attracts and holds the substrate 210 has been described. However, for example, while the substrate 210 is expanded or contracted by heating or cooling, the adsorption to the substrate 210 may be released so as not to prevent the substrate 210 from expanding or contracting. Further, the substrate holder 220 may be caused to maintain thermal expansion or contraction of the substrate 210 by adsorbing the substrate 210 after expansion or contraction.

  Further, in the first and second embodiments, when the substrate 210 is directly attracted and held on the lower stage 170 without using the substrate holder 220, the substrate 210 is heated before or after the substrate 210 is heated or cooled. Adsorption may be stopped or re-adsorption. In this case, while the substrate 210 expands or contracts due to heating or cooling, the adsorption of the substrate 210 is stopped in the adsorption region of the lower stage 170 corresponding to the region in which deformation due to expansion or contraction occurs in the substrate 210. As a result, the substrate 210 is smoothly expanded or contracted.

  Further, the substrate 210 after being expanded or contracted may be adsorbed in the adsorption region where the adsorption has been stopped. Thereby, the lower stage 170 can maintain the deformation of the substrate 210 due to expansion or contraction.

  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.

  In addition, the execution order of each process such as operations, procedures, steps, and stages in the apparatus, system, program, and method shown in the claims, the specification, and the drawings is “before”, “prior to” ”Or the like, or the output of the previous process can be realized in any order except when used in the 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 does not necessarily mean that implementation in this order is essential. Absent.

DESCRIPTION OF SYMBOLS 100 Joining device, 110, 132 Case, 120 Loader, 122 Fork, 124 Fall prevention claw, 126 Folding arm, 130 Pressurizing device, 131 Loading port, 134 Pressing lower part, 136 Heating plate, 138 Surface plate, 140 Holder stocker, 150 Pre-aligner, 160 Aligner, 161 Bottom plate, 162 Frame, 163 Column, 165 Top plate, 167 Control unit, 169 Calculation unit, 170 Lower stage, 171, 191 Microscope, 172 Support plate, 173, 193 Heat source, 174 Swing drive Part, 175, 195 heat insulating material, 176 spherical seat, 177 vertical drive part, 178, 198 reflector, 180 drive part, 182 guide rail, 184 X direction drive part, 186 Y direction drive part, 190 upper stage, 197 load cell, 201 FOUP, 10 substrate, 212 laminated substrate, 214 notch, 216, 2161 to 2166 alignment mark, 218 element region, 220, 2201, 2202, 2203 substrate holder, 221 groove, 222 holding surface, 223 step, 224 flange portion, 225 electrothermal material portion 226 through hole, 227 buried electrode, 228 contact for power feeding, 229 separation unit, 230 clip, 233 variable attenuator, 234 piezoelectric material unit, 235, 237 switch, 236 current source, 238, 239 voltage source

Claims (22)

An action force control unit for applying an action force to at least one of the first substrate and the second substrate;
A substrate comprising: an overlapping portion that aligns and overlaps the first substrate and the second substrate while maintaining deformation generated in at least one of the first substrate and the second substrate by the acting force. Overlay device.   The substrate superposition apparatus according to claim 1, wherein the acting force control unit causes the acting force to act on a partial region of the first substrate. When the first substrate and the second substrate are overlapped, a plurality of alignment indicators provided on the first substrate and a plurality of alignment indicators provided on the second substrate are A calculation unit that calculates a target position for superimposition that minimizes the amount of positional deviation with respect to the reference position;
The substrate superposition apparatus according to claim 2, wherein the acting force control unit determines the partial area based on a calculation result by the calculation unit.   4. The calculation unit according to claim 3, wherein the calculation unit calculates the target position by excluding an alignment index included in the partial region of the plurality of alignment indexes and a corresponding alignment index of the second substrate. The board | substrate superimposition apparatus of description.   The acting force control unit is configured to calculate the acting force based on a positional deviation amount of the alignment index included in the partial region of the plurality of alignment indices with respect to the alignment index of the corresponding second substrate. The board | substrate superimposition apparatus of Claim 3 or Claim 4 to determine.   The substrate according to any one of claims 2 to 5, wherein the acting force control unit applies the acting force by extending or contracting the partial region of the first substrate while adsorbing the partial region. Superposition device.   The substrate superposing apparatus according to claim 6, wherein the acting force control unit applies the acting force by expanding or contracting while adsorbing the entire second substrate. A first stage for adsorbing the first substrate;
8. The substrate overlaying device according to claim 1, wherein the superimposing unit maintains the deformation by continuing at least the suction of the first substrate by the first stage. 9.   9. The superimposing unit stops adsorption of the adsorption region of the first stage in a region adjacent to the region where the deformation occurs when the acting force control unit applies the acting force. Substrate overlay device.   The said action force control part produces the said action force by controlling the 1st action force generation part provided in the 1st board | substrate holder holding the said 1st board | substrate at least. The board | substrate superimposition apparatus of any one of Claims.   The substrate overlaying device according to claim 10, wherein the overlaying unit maintains the deformation by continuing at least the suction of the first substrate by the first substrate holder.   The superposition unit stops adsorption of the adsorption region of the first substrate holder in a region adjacent to the region where the deformation occurs when the acting force control unit generates the acting force. The board | substrate superimposition apparatus of description.   The pressurization part which pressurizes said 1st substrate and said 2nd substrate which were piled up, and joins said 1st substrate and said 2nd substrate permanently, and any one of Claim 1-12 The board | substrate superimposition apparatus as described in a term.   The substrate stack according to claim 13, wherein the pressurizing unit pressurizes the first substrate and the second substrate that are superimposed while maintaining the deformation, and then heats the first substrate and the second substrate. Alignment device.   The substrate superposition apparatus according to claim 13 or 14, wherein the acting force control unit maintains the deformation until the first substrate and the second substrate are permanently bonded. A temperature control unit for generating a temperature difference between the first substrate and the second substrate;
The substrate superposition apparatus according to any one of claims 1 to 15, wherein the temperature control unit causes deformation of at least one of the first substrate and the second substrate due to the temperature difference. A holding surface for sucking and holding the substrate;
A plurality of suction portions that are provided corresponding to the holding surfaces divided into a plurality of regions and suck the substrate;
A substrate holder comprising a plurality of acting force generating portions provided corresponding to the holding surfaces divided into a plurality of regions and extending and contracting in the surface direction of the substrate.   The substrate holder according to claim 17, wherein the adsorption force of the substrate by the plurality of adsorption units maintains the deformation of the substrate deformed by at least one of the plurality of acting force generation units. A first substrate holder for sucking and holding the first substrate;
A second substrate holder for adsorbing and holding a second substrate facing the first substrate;
An action force control unit that deforms at least one of the first substrate and the second substrate by controlling an action force generation unit provided in at least one of the first substrate holder and the second substrate holder;
A substrate overlaying system comprising: an overlaying unit that superposes and aligns each other while maintaining the deformation by controlling a suction portion provided on at least one of the first substrate holder and the second substrate holder . An acting force generating step for causing deformation by causing an acting force to act on at least one of the first substrate and the second substrate;
And a superposition step of superposing the first substrate and the second substrate on each other while maintaining the deformation.   The said action force generation step produces the said deformation | transformation by making an action force act on the said single layer board | substrate when said 1st board | substrate and said 2nd board | substrate are a single layer board | substrate and a laminated substrate. Substrate overlay method. A device manufacturing method manufactured by superimposing a first substrate and a second substrate,
The step of overlaying the first substrate and the second substrate comprises:
An acting force generating step of causing an acting force to act on at least one of the first substrate and the second substrate to cause a deformation in the surface direction of the substrate;
A device manufacturing method comprising: an overlapping step of aligning and overlapping the first substrate and the second substrate while maintaining the deformation.

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