JP2015015269A - Bonding device, bonding system, bonding method, program, and computer storage medium - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a bonding device, a bonding system, a bonding method, a program, and a computer storage medium which are arranged for appropriately adjusting substrates to be bonded to each other in position in a horizontal direction to appropriately bond the substrates to each other.SOLUTION: A bonding device 41 for bonding wafers Wand Wto each other comprises: an upper chuck 160 for holding the upper wafer Won a lower surface thereof; a lower chuck 161 provided under the upper chuck 160 for holding the lower wafer Won an upper surface thereof; a first temperature-adjustment part 121 for adjusting the temperature of the upper wafer Wbefore the upper chuck 160 holds it to a first temperature; and a second temperature-adjustment part 122 for adjusting the temperature of the lower wafer Wbefore the lower chuck 161 holds it to a second temperature different from the first temperature.

Description

  The present invention relates to a bonding apparatus, a bonding system, a bonding method, a program, and a computer storage medium for bonding substrates together.

  In recent years, semiconductor devices have been highly integrated. When a plurality of highly integrated semiconductor devices are arranged in a horizontal plane and these semiconductor devices are connected by wiring to produce a product, the wiring length increases, thereby increasing the wiring resistance and wiring delay. There is concern about becoming.

  Thus, it has been proposed to use a three-dimensional integration technique in which semiconductor devices are stacked three-dimensionally. In this three-dimensional integration technology, for example, two semiconductor wafers (hereinafter referred to as “wafers”) are bonded using a bonding system described in Patent Document 1. For example, the bonding system includes a surface modification device (surface activation device) that modifies the surface to which the wafer is bonded, a surface hydrophilization device that hydrophilizes the surface of the wafer modified by the surface modification device, And a bonding apparatus for bonding wafers whose surfaces have been hydrophilized by the surface hydrophilizing apparatus. In this bonding system, the surface of the wafer is subjected to plasma treatment in the surface modification device to modify the surface, and the surface is hydrophilized by supplying pure water to the surface of the wafer in the surface hydrophilization device. Thereafter, two wafers are vertically arranged opposite to each other in the bonding apparatus (hereinafter, the upper wafer is referred to as an “upper wafer” and the lower wafer is referred to as a “lower wafer”), and the upper chuck is held by suction. The wafer and the lower wafer adsorbed and held by the lower chuck are bonded by van der Waals force and hydrogen bond (intermolecular force).

JP 2011-181633 A

  By the way, due to various external factors before being held by the upper chuck and the lower chuck, the upper wafer and the lower wafer may be expanded and contracted, and the amount of expansion / contraction may be different between the upper wafer and the lower wafer. In such a case, when the wafers are bonded to each other, the upper wafer and the lower wafer are displaced in the horizontal direction and bonded. For example, in a bonded wafer (hereinafter referred to as “superimposed wafer”), even if the center portions of the upper wafer and the lower wafer are coincident with each other, a positional deviation occurs in the horizontal direction at the outer peripheral portion.

  However, in the joining system described in Patent Document 1, no consideration is given to suppressing horizontal displacement of the superposed wafer. Therefore, there is room for improvement in the conventional bonding process between wafers.

  This invention is made | formed in view of this point, and it aims at adjusting the horizontal position of the board | substrates joined together appropriately, and performing the joining process of the said board | substrates appropriately.

  In order to achieve the above object, the present invention is a bonding apparatus for bonding substrates to each other, and is provided below a first holding unit that holds a first substrate on a lower surface and the first holding unit. A second holding unit for holding the second substrate on the upper surface, and a first temperature adjusting unit for adjusting the temperature of the first substrate before being held by the first holding unit to the first temperature, And a second temperature adjusting unit that adjusts the temperature of the second substrate before being held by the second holding unit to a second temperature different from the first temperature. .

  According to the present invention, before being held by the first holding portion and the second holding portion, that is, before joining, the first substrate and the second temperature adjusting portion are respectively used by the first temperature adjusting portion and the second temperature adjusting portion. The substrates can be adjusted to different temperatures. Then, for example, even when the first substrate and the second substrate expand and contract, respectively, and the expansion and contraction amounts are different, by adjusting the first substrate and the second substrate to different temperatures as in the present invention, The first substrate and the second substrate can be expanded and contracted to different dimensions, and the difference between the expansion and contraction amounts can be absorbed. That is, the difference in the amount of expansion / contraction between the first substrate and the second substrate can be absorbed by the temperature difference between the first substrate and the second substrate. Thereby, the horizontal position of the 1st board | substrate and 2nd board | substrate to be joined can be adjusted appropriately, and the joining process of the said 1st board | substrate and a 2nd board | substrate can be performed appropriately.

  In Patent Document 1 described above, in order to promote van der Waals force and hydrogen bonding, a cooling mechanism is provided in the first holding unit and the second holding unit to cool the first substrate and the second substrate. While joining, it is described. However, in the invention of Patent Document 1, as in the present invention, the temperature of the first substrate before being held by the first holding unit and the temperature of the second substrate before being held by the second holding unit are adjusted. Nothing has been done and the first and second substrates have not been adjusted to different temperatures.

  It is also conceivable to adjust the temperatures of the first substrate and the second substrate before bonding using the cooling mechanism described in Patent Document 1. However, in such a case, the temperature of the first substrate and the second substrate is adjusted after being held by the first holding unit and the second holding unit, respectively, and the temperature adjustment takes a predetermined time. If it does so, the timing which starts the joining process of a 1st board | substrate and a 2nd board | substrate will be overdue, and a joining process cannot be performed rapidly.

  In this regard, since the first temperature control unit and the second temperature control unit of the present invention are provided separately from the first holding unit and the second holding unit, the first substrate and the second temperature control unit are bonded to each other before bonding. Even if the temperature of the substrate is adjusted, there is no influence on the timing of starting the bonding process between the first substrate and the second substrate. For this reason, the throughput of the bonding process can be improved.

  The bonding apparatus includes an imaging unit that images a superposed substrate in which a first substrate and a second substrate are bonded, and a first substrate and a second substrate in the superposed substrate based on an image captured by the imaging unit. And a control unit that sets a temperature difference between the first temperature and the second temperature based on the inspection result.

  The imaging unit may include an infrared camera.

  Each of the first substrate and the second substrate may be a semiconductor substrate on which a device is formed.

  The bonding apparatus includes a first substrate, a second substrate, a second substrate, and a first substrate, a second substrate, and a second substrate, which are loaded and unloaded between the first substrate and the second substrate. The substrate may further include a transition for temporarily placing the substrate or the superposed substrate, and the first temperature control unit and the second temperature control unit may be provided so as to be stacked on the transition.

  The bonding apparatus further includes a position adjusting mechanism that adjusts a horizontal direction of the first substrate or the second substrate, and the first temperature adjusting unit and the second temperature adjusting unit are respectively positioned at the position. The adjusting mechanism may be provided.

  Another aspect of the present invention is a bonding system including the bonding apparatus, wherein a processing station including the bonding apparatus, a first substrate, a second substrate, or a first substrate and a second substrate are provided. A plurality of bonded superposed substrates, and a loading / unloading station for loading / unloading the first substrate, the second substrate, or the superposed substrate to / from the processing station. Surface modifying device for modifying the surface to which the substrate or the second substrate is bonded, and surface hydrophilization for hydrophilizing the surface of the first substrate or the second substrate modified by the surface modifying device An apparatus, and a transfer device for transferring the first substrate, the second substrate, or the superposed substrate to the surface modification device, the surface hydrophilization device, and the bonding device, and the bonding device In the surface hydrophilizing device, the surface is hydrophilic. It is characterized by bonding a first substrate and a second substrate that is.

  According to another aspect of the present invention, there is provided a bonding method for bonding substrates to each other, the first step of adjusting the temperature of the first substrate to the first temperature by the first temperature adjusting unit, and the second step. A second step of adjusting the temperature of the second substrate to a second temperature different from the first temperature by the temperature adjusting unit; and the first substrate temperature-controlled in the first step A first substrate held by the first holding unit after holding the second substrate held by the lower surface of the holding unit and holding the second substrate temperature-adjusted in the second step by the upper surface of the second holding unit; And a third step of bonding the second substrate held by the second holding portion so as to face each other.

  In the bonding method, after the third step, a fourth step of imaging the superposed substrate in which the first substrate and the second substrate are bonded by the imaging unit, and an image captured in the fourth step Based on the fifth step of inspecting the relative position in the horizontal direction of the first substrate and the second substrate in the superposition substrate, based on the inspection result of the fifth step, the first temperature and the And a sixth step of setting a temperature difference between the second temperatures.

  The imaging unit may include an infrared camera, and in the fourth step, the superposition substrate may be imaged by the infrared camera.

  Each of the first substrate and the second substrate may be a semiconductor substrate on which a device is formed.

  The first step is after the horizontal direction of the first substrate is adjusted by the position adjusting mechanism and the front and back surfaces of the first substrate are reversed by the reversing mechanism. The second step may be performed before the third step, after the horizontal orientation of the second substrate is adjusted by the position adjusting mechanism.

  The first step and the second step may be performed while adjusting the horizontal orientations of the first substrate and the second substrate by the position adjusting mechanism, respectively.

  According to another aspect of the present invention, there is provided a program that operates on a computer of a control unit that controls the joining apparatus in order to cause the joining apparatus to execute the joining method.

  According to another aspect of the present invention, a readable computer storage medium storing the program is provided.

  ADVANTAGE OF THE INVENTION According to this invention, the horizontal direction position of the board | substrates joined can be adjusted appropriately, and the joining process of the said board | substrate can be performed appropriately.

It is a top view which shows the outline of a structure of the joining system concerning this Embodiment. It is a side view which shows the outline of the internal structure of the joining system concerning this Embodiment. It is a side view which shows the outline of a structure of an upper wafer and a lower wafer. It is a cross-sectional view which shows the outline of a structure of a joining apparatus. It is a longitudinal cross-sectional view which shows the outline of a structure of a joining apparatus. It is a side view which shows the outline of a structure of a position adjustment mechanism. It is a top view which shows the outline of a structure of a reversing mechanism. It is a side view which shows the outline of a structure of the inversion mechanism. It is a side view which shows the outline of a structure of the inversion mechanism. It is a side view which shows the outline of a structure of a holding | maintenance arm and a holding member. It is a side view which shows the outline of the internal structure of a joining apparatus. It is explanatory drawing which shows the outline of a structure of an upper imaging part. It is explanatory drawing which shows the outline of a structure of a lower imaging part. It is a longitudinal cross-sectional view which shows the outline of a structure of an upper chuck and a lower chuck. It is the top view which looked at the upper chuck from the lower part. It is the top view which looked at the lower chuck from the upper part. It is a flowchart which shows the main processes of a wafer joining process. It is explanatory drawing which shows a mode that the horizontal direction position of an upper imaging part and a lower imaging part is adjusted. It is explanatory drawing which shows a mode that the horizontal direction position of an upper wafer and a lower wafer is adjusted. It is explanatory drawing which shows a mode that the vertical direction position of an upper wafer and a lower wafer is adjusted. It is explanatory drawing which shows a mode that the center part of an upper wafer and the center part of a lower wafer are contacted, and are pressed. It is explanatory drawing which shows a mode that an upper wafer is sequentially contact | abutted to a lower wafer. It is explanatory drawing which shows a mode that the surface of the upper wafer and the surface of the lower wafer were made to contact | abut. It is explanatory drawing which shows a mode that the upper wafer and the lower wafer were joined. It is explanatory drawing which shows a mode that a superposition | polymerization wafer is test | inspected. It is explanatory drawing which shows a mode that a superposition | polymerization wafer is test | inspected.

  Embodiments of the present invention will be described below. FIG. 1 is a plan view showing the outline of the configuration of the joining system 1 according to the present embodiment. FIG. 2 is a side view illustrating the outline of the internal configuration of the joining system 1.

In the interface system 1, to bond the wafers W _U, W _L as substrate, for example two, as shown in FIG 3. Hereinafter, the wafer disposed on the upper side is referred to as “upper wafer W _U ” as the first substrate, and the wafer disposed on the lower side is referred to as “lower wafer W _L ” as the second substrate. Further, a bonding surface to which the upper wafer W _U is bonded is referred to as “front surface W _U1 ”, and a surface opposite to the front surface W _U1 is referred to as “back surface W _U2 ”. Similarly, the bonding surface to which the lower wafer W _L is bonded is referred to as “front surface W _L1 ”, and the surface opposite to the front surface W _L1 is referred to as “back surface W _L2 ”. Then, in the bonding system 1, by joining the upper wafer W _U and _the lower wafer W _L, to form the overlapped wafer W _T as a polymerization substrate.

In the present embodiment, the upper wafer W _U is a semiconductor wafer as a product, and a device including a plurality of electronic circuits or the like is formed on the surface W _U1 , for example. Likewise there is also a semiconductor wafer to be a product lower wafer W _L, the device comprising, for example, a plurality of electronic circuits on the surface W _L1, and the like are formed. Further, the upper wafer W _U and _the lower wafer W _L, for example, a silicon wafer is used.

As shown in FIG. 1, the bonding system 1 carries in and out cassettes C _U , C _L , and C _T that can accommodate a plurality of wafers W _U and W _L and a plurality of superposed wafers W _T , respectively, with the outside. The loading / unloading station 2 and the processing station 3 including various processing apparatuses that perform predetermined processing on the wafers W _U , W _L , and the overlapped wafer W _T are integrally connected.

The loading / unloading station 2 is provided with a cassette mounting table 10. The cassette mounting table 10 is provided with a plurality of, for example, four cassette mounting plates 11. The cassette mounting plates 11 are arranged in a line in the horizontal X direction (vertical direction in FIG. 1). These cassette mounting plates 11, cassettes _C U to the outside of the interface system _1, C L, when loading and unloading the _{C T,} a cassette _{C U,} C L, it is possible to place the _{C T} . Thus, carry-out station 2, a wafer over multiple W _U, a plurality of lower wafer W _L, and is configured to be held by a plurality of overlapped wafer W _T. The number of cassette mounting plates 11 is not limited to the present embodiment, and can be arbitrarily determined. One of the cassettes may be used for collecting abnormal wafers. That is a cassette a wafer abnormality occurs in the bonding of the upper wafer W _U and _the lower wafer W _L, it can be separated from the other normal overlapped wafer W _T by various factors. In the present embodiment, among the plurality of cassettes C _T, using a one cassette C _T for the recovery of the abnormal wafer, and using other cassettes C _T for the accommodation of a normal overlapped wafer W _T.

In the loading / unloading station 2, a wafer transfer unit 20 is provided adjacent to the cassette mounting table 10. The wafer transfer unit 20 is provided with a wafer transfer device 22 that is movable on a transfer path 21 extending in the X direction. The wafer transfer device 22 is also movable in the vertical direction and around the vertical axis (θ direction), and includes cassettes C _U , C _L , C _T on each cassette mounting plate 11 and a third of the processing station 3 described later. The wafers W _U and W _L and the superposed wafer W _T can be transferred between the transition devices 50 and 51 in the processing block G3.

  The processing station 3 is provided with a plurality of, for example, three processing blocks G1, G2, and G3 including various devices. For example, a first processing block G1 is provided on the front side of the processing station 3 (X direction negative direction side in FIG. 1), and on the back side of the processing station 3 (X direction positive direction side in FIG. 1) Two processing blocks G2 are provided. Further, a third processing block G3 is provided on the loading / unloading station 2 side of the processing station 3 (Y direction negative direction side in FIG. 1).

For example, in the first processing block G1, a surface modification device 30 for modifying the surfaces W _U1 and W _L1 of the wafers W _U and W _L is disposed. In the surface modification device 30, for example, in a reduced pressure atmosphere, the oxygen gas that is the processing gas is excited, turned into plasma, and ionized. The oxygen ions are irradiated onto the surfaces W _U1 and W _L1 , and the surfaces W _U1 and W _L1 are plasma-treated and modified.

For example, the second processing block G2 includes, for example, a surface hydrophilizing device 40 that hydrophilizes the surfaces W _U1 and W _L1 of the wafers W _U and W _L with pure water and cleans the surfaces W _U1 and W _{L1. U,} bonding device 41 for bonding the W _L are arranged side by side in the horizontal direction of the Y-direction in this order from the carry-out station 2 side.

In the surface hydrophilizing apparatus 40, for example, wafer W _U held by the spin _chuck, while rotating the W _L, for supplying pure water the wafer W _U, on W _L. Then, the supplied pure water is diffused on the wafer _W U, _{W L} of the surface _{W U1, W L1,} surface _{W U1, W L1} is hydrophilized. The configuration of the joining device 41 will be described later.

For example, the third processing block G3, the wafer _W U as shown in FIG. 2, _{W L,} a transition unit 50, 51 of the overlapped wafer _{W T} are provided in two tiers from the bottom in order.

  As shown in FIG. 1, a wafer transfer region 60 is formed in a region surrounded by the first processing block G1 to the third processing block G3. For example, a wafer transfer device 61 is disposed in the wafer transfer region 60.

The wafer transfer device 61 has, for example, a transfer arm that can move around the vertical direction, horizontal direction (Y direction, X direction), and vertical axis. The wafer transfer device 61 moves in the wafer transfer region 60, and adds wafers W _U , W _L , and W to predetermined devices in the surrounding first processing block G1, second processing block G2, and third processing block G3. You can transfer the overlapping wafer _{W T.}

The above joining system 1 is provided with a controller 70 as shown in FIG. The control unit 70 is, for example, a computer and has a program storage unit (not shown). The program storage unit stores a program for controlling processing of the wafers W _U and W _L and the overlapped wafer W _{T in} the bonding system 1. The program storage unit also stores a program for controlling operations of driving systems such as the above-described various processing apparatuses and transfer apparatuses to realize later-described wafer bonding processing in the bonding system 1. The program is recorded on a computer-readable storage medium H such as a computer-readable hard disk (HD), a flexible disk (FD), a compact disk (CD), a magnetic optical desk (MO), or a memory card. May have been installed in the control unit 70 from the storage medium H.

Next, the structure of the joining apparatus 41 mentioned above is demonstrated. As shown in FIG. 4, the bonding apparatus 41 includes a processing container 100 that can seal the inside. The side surface of the wafer transfer area 60 side of the processing chamber 100, the wafer _W U, _{W L,} the transfer port 101 of the overlapped wafer _{W T} is formed, in the transfer port 101 opening and closing the shutter 102 is provided.

The inside of the processing container 100 is partitioned by the inner wall 103 into a transport area T1 and a processing area T2. The loading / unloading port 101 described above is formed on the side surface of the processing container 100 in the transfer region T1. In addition, on the inner wall 103, a loading / unloading port 104 for the wafers W _U and W _L and the overlapped wafer W _T is formed. Note that the atmosphere inside the processing region T2 is maintained at a predetermined temperature, for example, 25 ° C.

On the positive side in the X direction of the transfer area T1, as shown in FIGS. 4 and 5, a transition 110 for temporarily placing the wafers W _U and W _L and the superposed wafer W _T and the wafers W _U and W _The temperature control mechanism 120 is provided by laminating the temperature of _L. The transition 110 is formed in, for example, two stages, and any two of the wafers W _U , W _L , and the superposed wafer W _T can be placed at the same time.

  The temperature adjustment mechanism 120 includes a first temperature adjustment unit 121 and a second temperature adjustment unit 122. The first temperature control unit 121 and the second temperature control unit 122 are stacked on the transition 110. In the present embodiment, one each of the first temperature adjustment unit 121 and the second temperature adjustment unit 122 is provided, but the number of these is not limited to this, and two or more are provided. May be.

The first temperature adjusting unit 121 has a first temperature regulating plate 123 for regulating the upper wafer W _U to the first temperature. For example, a Peltier element (not shown) is incorporated in the first temperature adjustment plate 123. The temperature of the first temperature regulating plate 123 is controlled by, for example, the control unit 70, _the upper wafer W _U on the first temperature regulating plate 123 is adjusted to the first temperature.

On the first temperature regulating plate 123, a gap pin 124 for holding the outer peripheral portion of the upper wafer W _U is more, for example, are three provided. Upper wafer W _U is its front and back surfaces by the reversing mechanism 150 as will be described later is inverted, i.e. the surface W _U1 is transported to the first temperature control unit 121 in a state of facing downward. In the first temperature adjustment unit 121, the outer peripheral portion of the surface W _U1 of the upper wafer W _U is held by the gap pin 124, that is, the outer peripheral portion where no device is formed is held on the surface W _U1 . The device can be prevented from being damaged.

The second temperature adjusting unit 122 has a second temperature regulating plate 125 for regulating the lower wafer W _L to a second temperature. The second temperature adjustment plate 125 has the same configuration as that of the first temperature adjustment plate 123, and the second temperature adjustment plate 125 includes, for example, a Peltier element (not shown). Also on the second temperature regulating plate 125, the entire back surface _{W L2} of the lower wafer _{W L} is placed. The temperature of the second temperature regulating plate 125 is controlled by, for example, the control unit 70, the lower wafer W _L placed on the second temperature regulating plate 125 is adjusted to a second temperature.

A first temperature above the wafer W _U at the first temperature adjusting unit 121, a second temperature below the wafer W _L at the second temperature adjusting unit 122 are set to different temperatures in the control unit 70.

Specifically, advance to Setsugo the Weha _W U, _{W L} in Setsugo device 41, by imaging a the junction polymerisation Weha _{W T,} Weha _W U Niokeru the polymerization Weha _{W T,} of _{W L} horizontal Check relative position. When the wafers W _U and W _L expand and contract, and the expansion and contraction amounts differ, the relative positions of the wafers W _U and W _L shift. In the inspection, the amount of displacement in the horizontal direction, that is, the difference between the expansion and contraction amounts is measured. Here, the upper wafer W _U and the lower wafer W _L, the shape changes when the temperature changes. For example, in the case of a silicon wafer, when the temperature rises by 1 ° C., the diameter increases by several microns due to thermal expansion. Therefore, based on the inspection result, the temperature difference between the first temperature and the second temperature is set so that the difference between the expansion amounts of the wafers W _U and W _L becomes zero. In the present embodiment, this temperature difference is set to 1 ° C.

In addition, either the first temperature or the second temperature is set to the same temperature as the atmosphere of the processing region T2. The wafer W _U or wafer W _L is temperature adjusted so may not be stretchable by a temperature variation in the processing region T2. In the present embodiment, the first temperature is set to the same temperature as the atmosphere of the processing region T2. Thus, for example, the first temperature is set to 25 ° C. and the second temperature is set to 26 ° C.

Incidentally, these first temperature and the second wafer W is used to set the temperature _U, the W _L, may be used wafer for inspection, may be used wafer products. In the case of using a product wafer, steps S16 and S17 described later are performed to set the first temperature and the second temperature.

A wafer transfer mechanism 130 is provided in the transfer area T1. The wafer transfer mechanism 130 has, for example, a transfer arm that is movable in the vertical direction, the horizontal direction (Y direction, X direction), and the vertical axis. Then, the wafer transfer mechanism 130 can transport wafers _W U, _{W L,} the overlapped wafer _{W T} between the inside transfer region T1, or a transfer region T1 and the processing region T2.

A position adjusting mechanism 140 that adjusts the horizontal direction of the wafers W _U and W _L is provided on the X direction negative direction side of the transfer region T1. As shown in FIG. 6, the position adjusting mechanism 140 includes a base 141, a holding unit 142 that holds and rotates the wafers W _U and W _L by a pin chuck method, and positions of notches of the wafers W _U and W _L. And a detecting unit 143 for detecting. Note that the pin chuck method of the holding portion 142 is the same as the pin chuck method in the upper chuck 160 and the lower chuck 161 described later, and thus description thereof is omitted. In the position adjustment mechanism 140, the position of the notches of the wafers W _U and W _L is detected by the detection unit 143 while rotating the wafers W _U and W _L held by the holding unit 142. The horizontal direction of the wafers W _U and W _L is adjusted by adjusting the position.

Further, in the transfer region T1 is reversing mechanism 150 for reversing the front and rear surfaces of the upper wafer W _U as shown in FIG. 4 is provided. Reversing mechanism 150 has a holding arm 151 which holds the upper wafer _{W U} as shown in FIGS. 7-9. The holding arm 151 extends in the horizontal direction (Y direction in FIGS. 7 and 8). Also the holding arm 151 is provided on the holding member 152 for holding the upper wafer W _U, for example four positions. As shown in FIG. 10, the holding member 152 is configured to be movable in the horizontal direction with respect to the holding arm 151. Also on the side surface of the holding member 152, the cutout 153 for holding the outer peripheral portion of the upper wafer W _U is formed. Then, these holding member 152 can hold sandwich the upper wafer W _U.

As shown in FIGS. 7 to 9, the holding arm 151 is supported by a first driving unit 154 including a motor or the like, for example. By this first drive unit 154, the holding arm 151 is rotatable around a horizontal axis. The holding arm 151 is rotatable about the first drive unit 154 and is movable in the horizontal direction (Y direction in FIGS. 7 and 8). Below the first drive unit 154, for example, a second drive unit 155 including a motor or the like is provided. The second driving unit 155 allows the first driving unit 154 to move in the vertical direction along the support pillar 156 extending in the vertical direction. This way the first driving unit 154 the second driving unit 155, _the upper wafer W _U held by the holding member 152 is movable in the vertical direction and the horizontal direction together with the pivotable about a horizontal axis. In addition, the upper wafer W _U held by the holding member 152 can move between the position adjusting mechanism 140 and an upper chuck 160 described later by rotating around the first driving unit 154.

The processing region T2, the upper chuck 160 as a first holding unit for attracting and holding the upper wafer W _U at the lower surface as shown in FIGS. 4 and 5, the suction holding and mounting the lower wafer W _L with the upper surface A lower chuck 161 is provided as a second holding portion. The lower chuck 161 is provided below the upper chuck 160 and is configured to be disposed so as to face the upper chuck 160. That is, the lower is held on the wafer W _U and the lower chuck 161 on which is held by the upper chuck 160 wafer W _L is adapted to be placed opposite.

  As shown in FIGS. 4, 5, and 11, the upper chuck 160 is supported by an upper chuck support 170 provided above the upper chuck 160. The upper chuck support 170 is provided on the ceiling surface of the processing container 100. That is, the upper chuck 160 is fixed to the processing container 100 via the upper chuck support 170.

The upper chuck support portion 170, the upper imaging unit 171 to image the surface _{W L1} of the lower wafer _{W L} held by the lower chuck 161 is provided. That is, the upper imaging unit 171 is provided adjacent to the upper chuck 160.

  The upper imaging unit 171 includes an infrared camera 172 and a visible light camera 173 as shown in FIG. The infrared camera 172 is a camera that acquires an infrared image. Specifically, the infrared camera 172 includes a sensor 174, a lens 175 connected to the sensor 174, and a shutter 176 provided between the sensor 174 and the lens 175. The visible light camera 173 is a camera that acquires a visible light image. Specifically, the visible light camera 173 includes a sensor 177, a lens 175 connected to the sensor 177, and a shutter 178 provided between the sensor 177 and the lens 175. The lens 175 is provided in common for the infrared camera 172 and the visible light camera 173.

  The upper imaging unit 171 can perform imaging using the infrared camera 172 and imaging using the visible light camera 173 by opening and closing the shutters 176 and 178, respectively.

  As shown in FIGS. 4, 5, and 11, the lower chuck 161 is supported by a first lower chuck moving unit 180 provided below the lower chuck 161. The first lower chuck moving unit 180 is configured to move the lower chuck 161 in the horizontal direction (X direction) as described later. The first lower chuck moving unit 180 is configured to be able to move the lower chuck 161 in the vertical direction and to rotate about the vertical axis.

The first lower chuck moving unit 180 is provided with a lower imaging unit 181 that images the surface W _U1 of the upper wafer W _U held by the upper chuck 160. That is, the lower imaging unit 181 is provided adjacent to the lower chuck 161.

  The lower imaging unit 181 has a visible light camera 182 as shown in FIG. Specifically, the visible light camera 182 includes a sensor 183 and a lens 184 connected to the sensor 183.

  As shown in FIGS. 4, 5, and 11, the first lower chuck moving unit 180 is provided on the lower surface side of the first lower chuck moving unit 180 and extends in the horizontal direction (X direction). 185 and 185 are attached. The first lower chuck moving unit 180 is configured to be movable along the rail 185.

  The pair of rails 185 and 185 are disposed on the second lower chuck moving portion 186. The second lower chuck moving part 186 is provided on the lower surface side of the second lower chuck moving part 186 and is attached to a pair of rails 187 and 187 extending in the horizontal direction (Y direction). The second lower chuck moving portion 186 is configured to be movable along the rail 187, that is, configured to move the lower chuck 161 in the horizontal direction (Y direction). The pair of rails 187 and 187 are disposed on a mounting table 188 provided on the bottom surface of the processing container 100.

  Next, detailed configurations of the upper chuck 160 and the lower chuck 161 of the bonding apparatus 41 will be described.

The upper chuck 160 employs a pin chuck system as shown in FIGS. Upper chuck 160 includes a body portion 190 having at least upper wafer W _U is greater than the diameter in a plan view. A plurality of pins 191 that are in contact with the back surface W _U2 of the upper wafer W _U are provided on the lower surface of the main body 190. In addition, an outer wall portion 192 that supports the outer peripheral portion of the back surface W _U2 of the upper wafer W _U is provided on the lower surface of the main body portion 190. The outer wall portion 192 is provided in an annular shape outside the plurality of pins 191.

The lower surface of the main body portion 190, inner region 193 of the outer wall portion 192 (hereinafter, there. Is referred suction region 193), the suction port 194 for evacuating the upper wafer _{W U} is formed. The suction ports 194 are formed at two locations on the outer peripheral portion of the suction region 193, for example. A suction pipe 195 provided inside the main body 190 is connected to the suction port 194. Further, a vacuum pump 196 is connected to the suction pipe 195 via a joint.

Then, the suction region 193 formed surrounded by the upper wafer W _U , the main body 190 and the outer wall 192 is evacuated from the suction port 194, and the suction region 193 is decompressed. At this time, since the outside atmosphere suction area 193 is at atmospheric pressure, the upper wafer W _U is pushed into the suction region 193 side by an amount corresponding atmospheric pressure is reduced, the upper wafer W _U is held by suction on the chuck 160 The

In such a case, since the plurality of pins 191 have a uniform height, the flatness of the lower surface of the upper chuck 160 can be reduced. Thus in the flat lower surface of the upper chuck 160 (by reducing the lower surface flatness), it is possible to suppress the distortion of the vertical direction of the wafer W _U after being held by the upper chuck 160. Since the back surface W _U2 of the upper wafer W _U is supported by a plurality of pins 191, when releasing the vacuum of the upper wafer W _U by the upper chuck 160, the on wafer W _U is easily peeled off from the upper chuck 160 .

A through hole 197 that penetrates the main body 190 in the thickness direction is formed at the center of the main body 190. The central portion of the body portion 190 corresponds to the central portion of the upper wafer W _U which is sucked and held on the chuck 160. A push pin 201 of a push member 200 described later is inserted into the through hole 197.

On the upper surface of the upper chuck 160, pressing member 200 for pressing the central portion of the upper wafer W _U it is provided. The pushing member 200 has a cylinder structure, and has a pushing pin 201 and an outer cylinder 202 serving as a guide when the pushing pin 201 moves up and down. The push pin 201 can be moved up and down in the vertical direction through a through-hole 197 by, for example, a drive unit (not shown) incorporating a motor. Then, the pressing member 200, the wafer W _U to be described _later, at the time of bonding of W _L, it can be pressed by contacting the center portion of the center and lower wafer W _L of the upper wafer W _U.

As shown in FIGS. 14 and 16, the lower chuck 161 employs a pin chuck system in the same manner as the upper chuck 160. Lower chuck 161 includes a body portion 210 having at least lower wafer W _L is greater than the diameter in a plan view. The upper surface of the main body portion 210, a plurality of pins 211 in contact with the back surface _{W L2} of the lower wafer _{W L} is provided. Also on the upper surface of the main body portion 210, outer wall 212 for supporting the outer peripheral portion of the back surface W _L2 of the lower wafer W _L is provided. The outer wall portion 212 is annularly provided outside the plurality of pins 211.

The upper surface of the main body portion 210, inner region 213 of the outer wall portion 212 (hereinafter, referred suction area 213 is.) In, suction port 214 for evacuating the lower wafer _{W L} are formed. A suction pipe 215 provided inside the main body 210 is connected to the suction port 214. For example, two suction pipes 215 are provided. Further, a vacuum pump 216 is connected to the suction pipe 215.

Then, the suction region 213 formed by being surrounded by the lower wafer W _L , the main body portion 210 and the outer wall portion 212 is evacuated from the suction port 214, and the suction region 213 is decompressed. At this time, since the outside atmosphere suction region 213 is at atmospheric pressure, lower wafer W _L is pushed toward the suction region 213 by only atmospheric pressure correspondingly reduced in pressure, the lower wafer W _L is sucked and held on the lower chuck 161 The

In this case, since the height of the plurality of pins 211 is uniform, the flatness of the upper surface of the lower chuck 161 can be reduced. Further, for example, even when particles are present in the processing container 100, it is possible to suppress the presence of particles on the upper surface of the lower chuck 161 because the interval between the adjacent pins 211 is appropriate. Thus in the flat upper surface of the lower chuck 161 (by reducing the flatness of the upper surface), it is possible to suppress distortion in the vertical direction of the lower wafer W _L held by the lower chuck 161. Since the rear surface W _L2 of the lower wafer W _L is supported by a plurality of pins 211, when releasing the vacuum of the lower wafer W _L by the lower chuck 161, being easily separated the lower wafer W _L from the lower chuck 161 .

  Near the center of the main body 210, through holes 217 that penetrate the main body 210 in the thickness direction are formed, for example, at three locations. And the raising / lowering pin provided below the 1st lower chuck | zipper moving part 180 is penetrated by the through-hole 217. As shown in FIG.

The outer peripheral portion of the main body portion 210, the wafer _W U, _{W L,} or jump out from the overlapped wafer _{W T} is lower chuck 161, the guide member 218 to prevent the sliding is provided. The guide members 218 are provided at a plurality of positions, for example, at four positions at equal intervals on the outer periphery of the main body 210.

  Note that the operation of each unit in the bonding apparatus 41 is controlled by the control unit 70 described above.

Next, a method for bonding the wafers W _U and W _L performed using the bonding system 1 configured as described above will be described. FIG. 17 is a flowchart showing an example of main steps of the wafer bonding process.

First, the cassette C _U, the cassette C _L accommodating the lower wafer W _L of the _plurality, and the empty cassette C _T is a predetermined cassette mounting plate 11 of the carry-out station 2 accommodating the wafers W _U on the plurality Placed on. Thereafter, _the upper wafer W _U in the cassette C _U is taken out by the wafer transfer device 22 is conveyed to the transition unit 50 of the third processing block G3 in the processing station 3.

Then the upper wafer W _U is transferred to the surface modification apparatus 30 of the first processing block G1 by the wafer transfer apparatus 61. In the surface reforming apparatus 30, oxygen gas, which is a processing gas, is excited and turned into plasma and ionized under a predetermined reduced-pressure atmosphere. The oxygen ions are irradiated onto the surface W _U1 of the upper wafer W _U , and the surface W _U1 is subjected to plasma treatment. Then, the surface W _U1 of the upper wafer W _U is modified (Step S1 in FIG. 17).

Then the upper wafer W _U is transferred to a surface hydrophilizing apparatus 40 of the second processing block G2 by the wafer transfer apparatus 61. In the surface hydrophilizing device 40, while rotating the upper wafer W _U held by the spin chuck, for supplying pure water onto the onto the wafer W _U. Then, the supplied pure water is diffused over the front surface W _U1 of the upper wafer W _U, the surface W _U1 to hydroxyl (silanol group) in _the upper wafer W _U which are modified in the surface modification apparatus 30 is the attached The surface W _U1 is hydrophilized. Further, the surface W _U1 of the upper wafer W _U is cleaned with the pure water (step S2 in FIG. 17).

Then the upper wafer W _U is transferred to the bonding apparatus 41 of the second processing block G2 by the wafer transfer apparatus 61. Upper wafer _{W U} which is carried into the joining device 41 is conveyed to the position adjusting mechanism 140 by the wafer transfer mechanism 130 via the transition 110. Then the position adjusting mechanism 140, the horizontal orientation of the upper wafer _{W U} is adjusted (step S3 in FIG. 17).

Thereafter, the upper wafer _{W U} is transferred from the position adjusting mechanism 140 to the holding arm 151 of the reversing mechanism 150. Subsequently, in transfer region T1, by reversing the holding arm 151, the front and back surfaces of the upper wafer W _U is inverted (step S4 in FIG. 17). That is, the surface W _U1 of the upper wafer W _U is directed downward.

Thereafter, the upper wafer _{W U} by reversing mechanism 150 is conveyed to a first temperature adjusting unit 121. In the first temperature adjusting unit 121, the upper wafer _{W U} is held on the gap pin 124 is adjusted by the first temperature regulating plate 123 a first temperature, for example, 25 ° C. (Step S5 in FIG. 17).

Thereafter, the upper wafer _{W U} by reversing mechanism 150 is conveyed below the upper chuck 160. Then, the upper wafer W _U is delivered from the reversing mechanism 150 to the upper chuck 160. Upper wafer _{W U,} the back surface _{W U2} above the chuck 160 is held by suction (step S6 in FIG. 17). Specifically, the vacuum pump is activated 196, and vacuum suction area 193 from the suction port 194, the upper wafer _{W U} is attracted and held on the chuck 160.

The upper wafer W _U which is held by the upper chuck 160 as is regulated in the step S5 as described above for example 25 ° C.. That is, the upper wafer W _U is regulated to the same temperature as the ambient temperature of the treatment region T2. Therefore, without the upper wafer W _U is stretchable by a temperature change, it does not change its shape and dimensions.

During the processing of steps S1~S6 described above on the wafer W _U is being performed, the processing of the lower wafer W _L Following the on wafer W _U is performed. First, the lower wafer W _L in the cassette C _L is taken out by the wafer transfer device 22 is conveyed to the transition unit 50 in the processing station 3.

Lower wafer _{W L} then is conveyed to the surface modification apparatus 30 by the wafer transfer apparatus 61, the surface _{W L1} of the lower wafer _{W L} is modified (step S7 in FIG. 17). Note that modification of the surface _{W L1} of the lower wafer _{W L} in step S7, is similar to the process S1 described above.

Thereafter, the lower wafer _{W L,} is transported to the surface hydrophilizing apparatus 40 by the wafer transfer apparatus 61, the surface _{W L1} of the lower wafer _{W L} is the surface _{W L1} together is hydrophilized is cleaned (Fig. 17 step S8 ). Incidentally, hydrophilic and cleaning of the surface W _L1 of the lower wafer W _L in step S8, is similar to the process S2 described above.

Thereafter, the lower wafer _{W L} is transported to the bonding apparatus 41 by the wafer transfer apparatus 61. Lower wafer _{W L} which is transported to the bonding unit 41 is conveyed to the position adjusting mechanism 140 by the wafer transfer mechanism 130 via the transition 110. Then the position adjusting mechanism 140, the horizontal orientation of the lower wafer _{W L} are adjusted (step S9 in FIG. 17).

Thereafter, the lower wafer _{W L} by the wafer transfer mechanism 130 is conveyed to the second temperature adjusting unit 122. In the second temperature adjusting unit 122, the upper wafer _{W U} is placed on the second temperature regulating plate 125 is adjusted second temperature, for example, 26 ° C. (Step S10 in FIG. 17).

Thereafter, the lower wafer _{W L} is transferred to the lower chuck 161 by the wafer transfer mechanism 130, the back surface _{W L2} is held by suction to the lower chuck 161 (step S11 in FIG. 17). Specifically, the vacuum pump is activated 216, and vacuum suction area 213 from the suction port 214, the lower wafer _{W L} is sucked and held by the lower chuck 161.

The lower wafer W _L held by the lower chuck 161 as is adjusted, for example, 26 ° C. In step S10, as described above. That is, the lower wafer W _L is adjusted in a different temperature first temperature of the atmosphere temperature and the upper wafer W _U processing region T2 (25 ℃). Thus for 1 ℃ higher than the first temperature of the second temperature is above the wafer W _U of the lower wafer W _L, the lower wafer W _L is several μm greater expansion than the upper wafer W _U. Then, even if the amount of expansion and contraction of the upper wafer W _U and the lower wafer W _L before temperature control as described above is different, the dimensions of the upper wafer W _U and _the lower wafer W _L are the same.

Next, the adjusted horizontal position of the wafer W _U and the lower wafer held by the lower chuck 161 W _L after being held by the upper chuck 160.

As shown in FIG. 18, a plurality of predetermined reference points A1 to A3, for example, three reference points A1 to A3 are formed on the surface W _U1 of the upper wafer W _U , and similarly, the surface W _L1 of the lower wafer W _L is previously set on the surface W _L1. A plurality of predetermined reference points B1 to B3, for example, three points are formed. Reference point A1, A3 and B1, B3 is the reference point of the outer peripheral portion of the wafer _W U, _{W L,} respectively, reference points A2 and B2 is the reference point of the center portion of the wafer _W U, _{W L,} respectively. As these reference points A1 to A3 and B1 to B3, for example, predetermined patterns formed on the wafers W _L and W _U are used, respectively. In this embodiment, there are three reference points on the wafers W _L and W _U , but the number of reference points is not limited to this and can be arbitrarily set.

  First, as shown in FIG. 18, the horizontal positions of the upper imaging unit 171 and the lower imaging unit 181 are adjusted. Specifically, the lower chuck 161 is moved in the horizontal direction (X direction) by the first lower chuck moving unit 180 and the second lower chuck moving unit 186 so that the lower imaging unit 181 is positioned substantially below the upper imaging unit 171. And the Y direction). Then, the visible light camera 173 of the upper imaging unit 171 and the visible light camera 182 of the lower imaging unit 181 confirm the common target T, and the lower imaging unit 171 and the lower imaging unit 181 are aligned so that the horizontal positions match. The horizontal position of the imaging unit 181 is finely adjusted.

Next, as shown in FIG. 19, the lower chuck 161 is moved vertically upward by the first lower chuck moving unit 180, and then the horizontal positions of the upper chuck 160 and the lower chuck 161 are adjusted. Specifically, the visible light camera 173 of the upper imaging unit 171 is moved while the lower chuck 161 is moved in the horizontal direction (X direction and Y direction) by the first lower chuck moving unit 180 and the second lower chuck moving unit 186. successively imaging the reference point B1~B3 surface _{W L1} of the lower wafer _{W L} using. At the same time, the reference points A1 to A3 of the surface W _U1 of the upper wafer W _U are sequentially imaged using the visible light camera 182 of the lower imaging unit 181 while moving the lower chuck 161 in the horizontal direction. Incidentally, FIG. 19 are both imaging the reference point B1 of the lower wafer _{W L} by the upper image capturing section 171, shows how to image the reference point A1 of the surface _{W U1} of the upper wafer _{W U} by the lower imaging unit 181. The captured visible light image is output to the control unit 70. In the control unit 70, based on the captured visible light image with the visible light image and the lower image pickup unit 181 captured by the upper image capturing section 171, the reference point of the upper wafer W _U reference point A1~A3 and lower wafer W _L of The horizontal position of the lower chuck 161 is adjusted by the first lower chuck moving portion 180 and the second lower chuck moving portion 186 so that B1 to B3 match each other. Thus the horizontal position of the upper chuck 160 and lower chuck 161 is adjusted, the horizontal position of the upper wafer _{W U} and the lower wafer _{W L} are adjusted (step S12 in FIG. 17).

  The adjustment of the horizontal position is performed by moving the lower chuck 161 in the horizontal direction (X direction and Y direction) as described above, and rotating the lower chuck 161 by the first lower chuck moving unit 180. The direction of the lower chuck 161 is also adjusted.

Thereafter, as shown in FIG. 20, the lower chuck 161 is moved vertically upward by the first lower chuck moving unit 180 to adjust the vertical position of the upper chuck 160 and the lower chuck 161, and is held by the upper chuck 160. It has been on achieving an adjusted vertical position of the wafer W _U and the lower wafer held by the lower chuck 161 W _L (step S13 in FIG. 17). At this time, the distance between the surface W _L1 of the lower wafer W _L and the surface W _U1 of the upper wafer W _U is a predetermined distance, for example, 80 μm to 200 μm.

Next, the bonding process of the lower wafer W _L held on the wafer W _U and the lower chuck 161 on which is held by the upper chuck 160 is performed.

First, as shown in FIG. 21, the push pin 201 of the push member 200 is lowered to lower the upper wafer W _U while pressing the central portion of the upper wafer W _U. In this case, the pushing pin 201, the load such as the pressing pin 201 in the absence of the upper wafer _{W U} is 70μm moves, for example, 200g is applied. Then, the pressing member 200 is pressed by abutting the central portion of the central portion and the lower wafer _{W L} of the upper wafer _{W U} (step S14 in FIG. 17). At this time, since the suction port 194 of the upper chuck 160 is formed on the outer peripheral portion of the suction area 193, even when pressing the central portion of the upper wafer W _U by pressing member 200, the upper by the upper chuck 160 wafers W The outer periphery of _U can be held.

Then, the bonding is started between the central portion of the central portion and the lower wafer W _L of _the upper wafer W _U which pressed (thick line portion in FIG. 21). That is, since the surface W _U1 of the upper wafer W _U and the surface W _L1 of the lower wafer W _L are modified in steps S1 and S7, respectively, first, the van der Waals force (intermolecular) between the surfaces W _U1 and W _L1. Force) is generated, and the surfaces W _U1 and W _L1 are joined to each other. Furthermore, since the surface W _U1 of the upper wafer W _U and the surface W _L1 of the lower wafer W _L are hydrophilized in steps S2 and S8, respectively, hydrophilic groups between the surfaces W _U1 and W _L1 are hydrogen bonded (intermolecular). Force), the surfaces W _U1 and W _L1 are firmly bonded to each other.

Then, to stop the operation of the vacuum pump 196 while pressing the center portion of the center and lower wafer W _L of the upper wafer W _U by the pressing member 200 as shown in FIG. 22, the upper in the suction area 193 the wafer W Stop evacuation of _U. Then, the upper wafer _{W U} falls onto the lower wafer _{W L.} At this time, since the back surface W _U2 of the upper wafer W _U is supported by a plurality of pins 191, when releasing the vacuum of the upper wafer W _U by the upper chuck 160, the on wafer W _U is peeled from the upper chuck 160 It is easy. And toward the outer periphery from the center of the upper wafer W _U, stop evacuation of the upper wafer W _U, the upper wafer W _U abuts sequentially drop onto the lower wafer W _L, the surface W _U1 mentioned above, bonding by the van der Waals forces and hydrogen bonds between W _L1 are sequentially spreads. Thus, contact with the surface _{W U1} and the surface _{W L1} of the lower wafer _{W L} of the upper wafer _{W U} is entirely as shown in FIG. 23, _the upper wafer _{W U} and _the lower wafer _{W L} is bonded (step of FIG. 17 S15 ).

Thereafter, the push pin 201 of the push member 200 is raised to the upper chuck 160 as shown in FIG. Further, to stop the operation of the vacuum pump 216, to stop the evacuation of the lower wafer W _L in the suction region 213, stopping the suction and holding of the lower wafer W _L by the lower chuck 161. At this time, since the back surface W _L2 of the lower wafer W _L is supported by a plurality of pins 211, when releasing the vacuum of the lower wafer W _L by the lower chuck 161, peeling the under wafer W _L from the lower chuck 161 It is easy.

Next, inspection of the overlapped wafer _{W T} that _the upper wafer _{W U} and _the lower wafer _{W L} are joined as shown in FIGS. 25 and 26 (step S16 in FIG. 17). Incidentally, the wafer _W U in the overlapped wafer _{W T,} the bonding surface of _{W L,} a reference point which the reference point B1~B3 the upper wafer _{W U} reference point A1~A3 and lower wafer _{W L} of abuts respectively C1~ C3.

In step S16, the infrared camera 172 of the upper imaging unit 171 is used while moving the lower chuck 161 in the horizontal direction (X direction and Y direction) by the first lower chuck moving unit 180 and the second lower chuck moving unit 186. sequentially imaging an interior of a reference point C1~C3 the overlapped wafer _{W T} Te. In this case, infrared rays so transmitted through the overlapped wafer _{W T,} it is possible to image the inside of the reference point C1~C3 the overlapped wafer _{W T} by infrared camera 172. FIG. 25 shows a state in which image the reference point C1 of the overlapped wafer W _T by the upper imaging unit 171, FIG. 26 shows a state for capturing a reference point C2 of the overlapped wafer W _T by the upper image capturing section 171. The captured infrared image is output to the control unit 70. In the control unit 70, based on the infrared image captured by the infrared camera 172, the inspection of the overlapped wafer W _T is performed. That is, at the reference points C1 to C3, it is checked whether or not the reference points A1 to A3 and the reference points B1 to B3 match. Thus the overlapped wafer W _T, inspection of the horizontal relative positions of the upper wafer W _U and _the lower wafer W _L is performed.

The range in the inspection of the overlapped wafer W _T in the step S16, the reference point A1~A3 and the reference point B1~B3 matches, in addition to the case of completely coincide, the position deviation of each reference point of the desired Including the case of being within.

Then, based on the test result in step S16, a first temperature above the wafer W _U at the first temperature adjusting unit 121, the adjustment of the second temperature below the wafer W _L at the second temperature adjusting unit 122 This is performed (step S17 in FIG. 17). That is, the first temperature adjustment unit 121 and the second temperature adjustment unit 122 are feedback-controlled.

In step S17, when the inspection result is normal, the temperature adjustment of the first temperature adjustment unit 121 and the second temperature adjustment unit 122 is not performed. On the other hand, test if the result is abnormal, that is, when the upper wafer W _U and _the lower wafer W _L are joined horizontally offset, so that the position deviation of the horizontal direction is eliminated, the first temperature adjusting unit 121 a first temperature above the wafer W _U, a second temperature below the wafer W _L at the second temperature adjusting unit 122 are respectively set in. Then, it is possible to properly carry out the bonding process of the wafer W _U, W _L to be performed later. The temperature adjustment in step S17 is the same as the temperature adjustment in steps S5 and S10, and thus the description thereof is omitted.

Thereafter, the overlapped wafer W _T that has been completed inspected is conveyed to the transition unit 51 by the wafer transfer apparatus 61, it is conveyed to the cassette C _T of predetermined cassette mounting plate 11 by the wafer transfer apparatus 22 of the subsequent unloading station 2 . Thus, a series of wafers _W U, bonding process of _{W L} is completed.

According to the above embodiment, in steps S5 and S10 before bonding of wafers W _U and W _L , upper wafer W _U and lower wafer are respectively performed by first temperature adjustment unit 121 and second temperature adjustment unit 122. the W _L can be adjusted to different temperatures. Then, for example, wafer W _U and the lower wafer W _L on the previous temperature adjustment to stretch each, even if the amount of expansion and contraction are different, different on wafer W _U and the lower wafer W _L as in this embodiment by adjusting the temperature, it is possible to stretch the upper wafer W _U and the lower wafer W _L in different dimensions, it is possible to absorb the difference between the amount of expansion and contraction. That is, the difference between expansion and contraction of _the upper wafer W _U and _the lower wafer W _L, can be absorbed by the temperature difference between the upper wafer W _U and _the lower wafer W _L. Thus, the horizontal position of the upper wafer W _U and _the lower wafer W _L can be appropriately adjusted in step S12, to properly carry out the connecting process of the upper wafer W _U and _the lower wafer W _L in the step S14 and S15 Can do.

In this embodiment, although the second temperature difference of the temperature of the first temperature and lower wafer W _L of the upper wafer W _U and 1 ° C., without the temperature difference is not limited to this, for example, 2 It can be arbitrarily set to, for example, 3 ° C. So as to absorb the difference in expansion and contraction amount of the wafer W _U and the lower wafer W _L on the previous temperature control as described above, the temperature difference is set.

Further, the first temperature adjusting unit 121 and the second temperature control unit 122, since it is provided separately from the upper chuck 160 and lower chuck 161, even if the temperature control of the upper wafer W _U and _the lower wafer W _L, there is no influence of the timing of starting the adjustment of the position of the upper wafer W _U and _the lower wafer W _L. For this reason, the throughput of the bonding process can be improved.

Also, when performing the inspection of the overlapped wafer _{W T} in the step S16, since the infrared is transmitted through the overlapped wafer _{W T,} imaging an interior of a reference point C1~C3 the overlapped wafer _{W T} by infrared camera 172 of the upper image capturing section 171 be able to. Then, in a subsequent step S17, the inspection based on the result, the overlapped wafer _{W T} first temperature adjusting unit as a reference point B1~B3 the upper wafer _{W U} reference point A1~A3 and lower wafer _{W L} of matches in 121 and the second temperature adjusting unit 122 can be feedback controlled. Therefore, the first temperature of the first temperature adjustment unit 121 and the second temperature of the second temperature adjustment unit 122 can be appropriately adjusted, and the subsequent bonding process of the wafers W _U and W _L can be appropriately performed. Can be done.

Moreover, in this way it is possible to inspect the overlapped wafer W _T by joining device within 41, it is not necessary to provide a separate test device external to the joining device 41 can be inexpensive the manufacturing cost of the device. Since it examines the overlapped wafer W _T immediately after bonding the wafer W _U, the W _L together, the inspection result can be fed back in a timely subsequent bonding process, thereby improving the accuracy of the bonding process is .

  The first temperature control unit 121 and the second temperature control unit 122 are provided to be stacked on the transition 110, that is, the first temperature control is performed in an empty space in the conventional bonding apparatus described in Patent Document 1. The part 121 and the second temperature adjustment part 122 are arranged. For this reason, even if these 1st temperature control parts 121 and the 2nd temperature control part 122 are provided, the exclusive area of the joining apparatus 41 can be maintained small.

In addition to the bonding apparatus 41, the bonding system 1 includes a surface modifying apparatus 30 that modifies the surfaces W _U1 and W _L1 of the wafers W _U and W _L , and the surfaces W _U1 and W _L1 are made hydrophilic and the surfaces are made hydrophilic. Since the surface hydrophilizing device 40 for cleaning W _U1 and W _L1 is also provided, the wafers W _U and W _L can be efficiently bonded in one system. Accordingly, the throughput of the wafer bonding process can be further improved.

  In the bonding apparatus 41 of the above embodiment, the first temperature control unit 121 and the second temperature control unit 122 are provided by being stacked on the transition 110, but the present invention is not limited to this, and installed at an arbitrary place. Can do. For example, the first temperature adjustment unit 121 and the second temperature adjustment unit 122 may be provided in the processing region T2, or may be provided in the reversing mechanism 150 or the wafer transfer mechanism 130.

In addition, a temperature adjustment mechanism including a first temperature adjustment unit 121 and a second temperature adjustment unit 122 may be provided in the holding unit 142 of the position adjustment mechanism 140, for example. In this case, _the upper wafer W _U and _the lower wafer W _L is temperature adjusted immediately adjusted during adjustment the horizontal orientation by the position adjusting mechanism 140, or the horizontal orientation.

In any of the above cases, the same effect as in the above embodiment can be obtained, that is, the upper wafer W _U and the lower wafer W _L are adjusted to appropriate temperatures, and the wafers W _U , W _L are adjusted. The joining process can be performed appropriately and quickly.

  Moreover, although the 1st temperature control part 121 of the above embodiment had the 1st temperature control board 123 and the gap pin 124, it is not limited to this, A various structure can be taken. For example, instead of the first temperature control plate 123 and the gap pin 124, for example, a Peltier element (not shown) or the like may be incorporated in a chuck having the same configuration as the upper chuck 160.

In the joining device 41 of the above embodiment, the infrared camera 172 is provided in the upper imaging unit 171, but the infrared camera 172 may be provided in the lower imaging unit 181. Further, infrared cameras 172 may be provided in both the upper imaging unit 171 and the lower imaging unit 181. Case in which the infrared camera 172 to both the top imaging unit 171 and the lower image pickup unit 181, none of the upper chuck 160 and lower chuck 161, it is possible to hold the overlapped wafer W _T in which a plurality of wafers are stacked, bonded The degree of freedom of processing is improved.

In the above embodiment, the case where both the upper wafer W _U and the lower wafer W _L are product wafers has been described. However, in the present invention, for example, the upper wafer W _U is a product wafer, and the lower wafer W _L There and when a support wafer, the upper wafer W _U is a support wafer, the lower wafer W _L can be applied when a product wafer. However, when the wafer W _U, W _L is the product wafer both, for example the wafer W _U, or the like is required to achieve continuity of the through electrodes between W _L, especially the position in the horizontal direction of the wafer W _U, W _L Adjustments must be made strictly. In such a case, the problem of the positional displacement of the wafers W _U and W _{L in} the horizontal direction is prominent, and the present invention is particularly useful.

  In the bonding apparatus 41 of the above embodiment, the upper chuck 160 is fixed to the processing container 100 and the lower chuck 161 is moved in the horizontal direction and the vertical direction. On the contrary, the upper chuck 160 is moved in the horizontal direction and the vertical direction. And the lower chuck 161 may be fixed to the processing container 100. Alternatively, both the upper chuck 160 and the lower chuck 161 may be moved in the horizontal direction and the vertical direction.

In the bonding system 1 of the above embodiment, after bonding the wafers W _U and W _L by the bonding apparatus 41, the bonded wafer W _T may be further heated (annealed) at a predetermined temperature. By performing the heat treatment according to the overlapped wafer W _T, it is possible to more firmly bond the bonding interface.

  The preferred embodiments of the present invention have been described above with reference to the accompanying drawings, but the present invention is not limited to such examples. It is obvious for those skilled in the art that various modifications or modifications can be conceived within the scope of the idea described in the claims, and these naturally belong to the technical scope of the present invention. It is understood. The present invention is not limited to this example and can take various forms. The present invention can also be applied to a case where the substrate is another substrate such as an FPD (flat panel display) other than a wafer or a mask reticle for a photomask.

DESCRIPTION OF SYMBOLS 1 Bonding system 2 Loading / unloading station 3 Processing station 30 Surface modification apparatus 40 Surface hydrophilization apparatus 41 Bonding apparatus 61 Wafer transfer apparatus 70 Control part 110 Transition 120 Temperature adjustment mechanism 121 1st temperature adjustment part 122 2nd temperature adjustment part 130 wafer transfer mechanism 140 position adjusting mechanism 150 the reversing mechanism 160 upper chuck 161 lower chuck 171 top imaging unit 172 infrared camera 181 lower imaging unit A1~A3 reference point B1~B3 reference point C1~C3 reference point W _U on the wafer W _L under wafer W _T polymerization wafer

Claims (15)

A joining device for joining substrates,
A first holding unit for holding the first substrate on the lower surface;
A second holding unit that is provided below the first holding unit and holds the second substrate on the upper surface;
A first temperature adjusting unit that adjusts the temperature of the first substrate before being held by the first holding unit to a first temperature;
A second temperature adjusting unit that adjusts the temperature of the second substrate before being held by the second holding unit to a second temperature different from the first temperature; Joining device. An imaging unit that images a superposed substrate in which the first substrate and the second substrate are joined;
Based on the image picked up by the image pickup unit, the horizontal relative positions of the first substrate and the second substrate in the superposition substrate are inspected, and based on the inspection result, the first temperature and the second temperature The bonding apparatus according to claim 1, further comprising: a control unit that sets a temperature difference between the two temperatures. The joining apparatus according to claim 2, wherein the imaging unit includes an infrared camera. The bonding apparatus according to claim 1, wherein each of the first substrate and the second substrate is a semiconductor substrate on which a device is formed. In order to carry in and out the first substrate, the second substrate, or the superposed substrate in which the first substrate and the second substrate are bonded to each other, the first substrate, the second substrate, or the superposed substrate A transition for temporarily mounting
5. The bonding apparatus according to claim 1, wherein the first temperature adjusting unit and the second temperature adjusting unit are provided so as to be stacked on the transition. A position adjusting mechanism for adjusting the horizontal direction of the first substrate or the second substrate;
The joining apparatus according to claim 1, wherein the first temperature adjusting unit and the second temperature adjusting unit are provided in the position adjusting mechanism, respectively. A joining system comprising the joining device according to claim 1,
A processing station comprising the joining device;
Each of the first substrate, the second substrate, or a plurality of superposed substrates bonded with the first substrate and the second substrate can be held, and the first substrate, the second substrate, or the superposed over the processing station. A loading / unloading station for loading and unloading substrates,
The processing station is
A surface modification device for modifying a surface to which the first substrate or the second substrate is bonded;
A surface hydrophilizing device for hydrophilizing the surface of the first substrate or the second substrate modified by the surface modifying device;
A transport device for transporting the first substrate, the second substrate, or the polymerized substrate to the surface modification device, the surface hydrophilization device, and the bonding device;
In the joining apparatus, the first substrate and the second substrate whose surfaces are hydrophilized by the surface hydrophilizing device are joined together. A bonding method for bonding substrates,
A first step of adjusting the temperature of the first substrate to the first temperature by the first temperature adjustment unit;
A second step of adjusting the temperature of the second substrate to a second temperature different from the first temperature by a second temperature adjusting unit;
The first substrate adjusted in temperature in the first step is held on the lower surface of the first holding unit, and the second substrate adjusted in temperature in the second step is held on the upper surface of the second holding unit. And a third step of joining the first substrate held by the first holding portion and the second substrate held by the second holding portion so as to face each other. A joining method characterized. After the third step, a fourth step of imaging the superposed substrate in which the first substrate and the second substrate are bonded by the imaging unit;
A fifth step of inspecting a horizontal relative position between the first substrate and the second substrate in the superposed substrate based on the image captured in the fourth step;
The method according to claim 8, further comprising a sixth step of setting a temperature difference between the first temperature and the second temperature based on an inspection result of the fifth step. Joining method. The imaging unit includes an infrared camera,
The joining method according to claim 9, wherein in the fourth step, the superposed substrate is imaged by the infrared camera. The bonding method according to claim 8, wherein each of the first substrate and the second substrate is a semiconductor substrate on which a device is formed. The first step is after the horizontal direction of the first substrate is adjusted by the position adjusting mechanism and the front and back surfaces of the first substrate are reversed by the reversing mechanism. Done before,
The second step is performed after the horizontal direction of the second substrate is adjusted by the position adjusting mechanism and before the third step. The joining method according to any one of 11. The said 1st process and the said 2nd process are performed during adjustment of the horizontal direction of a 1st board | substrate and a 2nd board | substrate, respectively by a position adjustment mechanism, The Claims 8-11 characterized by the above-mentioned. The joining method according to any one of the above. A program that operates on a computer of a control unit that controls the joining apparatus in order to cause the joining apparatus to execute the joining method according to claim 8. A readable computer storage medium storing the program according to claim 14.

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