TWI612595B - Joining device, joining system, joining method and computer storage medium - Google Patents

Abstract

When the substrates are bonded to each other, the substrate is appropriately held, and The bonding process of the substrates to each other is appropriately performed.

Engagement device (41) having: upper chuck (140), on the upper wafer (W_UThe vacuum is applied to be held underneath; and the lower chuck (141) is disposed below the upper chuck (140) to the lower wafer (W)_LThe vacuum is applied and the adsorption is maintained thereon. The lower chuck (141) has a body portion (190) and a lower wafer (W)_LVacuuming; a plurality of pins (191) disposed on the body portion (190) and contacting the lower wafer W_LThe back surface; and a plurality of non-contact ribs (193-196) are concentrically arranged in a ring shape in the outer periphery of the body portion (190), and have a lower height than the support pin (191). Between adjacent non-contact ribs (193-196), a plurality of pins (191) are provided.

Description

Bonding device, bonding system, bonding method, and computer memory medium

The present invention relates to a bonding device for bonding substrates, a bonding system including the bonding device, a bonding method using the bonding device, a program, and a computer memory medium.

In recent years, there has been progress in the high integration of semiconductor elements. When a plurality of highly integrated semiconductor elements are placed in a horizontal plane, and the semiconductor elements are connected by wiring and commercialized, the wiring length becomes long, and thus the resistance of the wiring becomes large, and the wiring delay becomes large. Hey.

Therefore, there is a proposal to use a three-dimensional integrated technique in which semiconductor elements are stacked in three dimensions. In the three-dimensional integrated technique, for example, the bonding of two semiconductor wafers (hereinafter referred to as "wafers") is performed using the bonding system described in Patent Document 1. For example, the bonding system has: a surface modifying device that modifies the bonded surface of the wafer; a surface hydrophilizing device that hydrophilizes the surface of the wafer modified by the surface modifying device; and a bonding device Hydrophilizing the surface via the surface hydrophilization device The wafers are bonded to each other. In the bonding system, in the surface modification device, after the surface of the wafer is subjected to plasma treatment to modify the surface, in the surface hydrophilization device, pure water is supplied to the surface of the wafer to make the surface Hydrophilic. Thereafter, in the bonding apparatus, two wafers are arranged vertically (the lower wafer is referred to as "upper wafer", and the lower wafer is referred to as "lower wafer"). The upper wafer holding the adsorption on the upper chuck by the van der Waals force and hydrogen bonding (intermolecular force) is bonded to the lower wafer adsorbed and held by the lower chuck.

In the lower chuck described above, a so-called pin chuck method is used. In this case, the upper surface of the lower chuck can be made flat (the flatness of the upper surface can be reduced) so that the heights of the plurality of pins are uniform. Further, even in the case where, for example, fine particles are present in the joint device, it is possible to suppress the presence of fine particles on the lower chuck by adjusting the interval between the adjacent pins. As a result, the upper surface of the lower chuck is flattened in an attempt to suppress the vertical skew in the wafer held under the lower chuck.

[Previous Technical Literature] [Patent Document]

[Patent Document 1] Japanese Patent No. 5538613

Here, for example, a plurality of semiconductor elements are formed on the lower wafer, and therefore, in a general state in which the restraining force does not act on the lower wafer, the bending is performed to some extent. As a result, it is described in the above patent. When the lower chuck of Document 1 is used to evacuate only the lower wafer, it is particularly difficult to maintain the outer peripheral portion of the lower wafer, so that the outer peripheral portion maintains the bending. In this case, when the lower wafer and the upper wafer are bonded, the bonded wafers are skewed in the vertical direction.

Further, in this case, when the outer peripheral portion of the lower wafer is not flat, there is a space in which the distance between the bonded wafer and the lower wafer is small. In this space, when the upper wafer and the lower wafer are in contact, there is a possibility that the air between the upper wafer and the lower wafer cannot be completely ejected to the outside, and the bonded wafer is produced. The pores of the pores. Therefore, there is room for improvement in the bonding process of the wafer.

The present invention has been made in view of the above, and it is an object of the present invention to appropriately hold a substrate while bonding substrates, and to appropriately perform bonding processing of the substrates.

In order to achieve the above object, the present invention provides a bonding apparatus for bonding substrates, characterized in that: a first holding portion that vacuum-absorbs a first substrate and is held by a lower surface; and a second holding portion that is provided in the foregoing The second substrate is suctioned and held on the lower surface of the first holding portion, and the second holding portion has a main body portion for evacuating the second substrate, and a plurality of support pins are provided on the main body portion. And contacting the back surface of the second substrate; and the plurality of non-contact ribs are concentrically arranged in a ring shape in the outer peripheral portion of the body portion, and the height is lower than the support pin, and the adjacent non-contact is adjacent Between the ribs, the system is provided with the aforementioned complex Several expenses.

According to the present invention, a plurality of non-contact ribs are disposed on the outer circumference of the body portion, and a plurality of support pins are disposed between the adjacent non-contact ribs, that is, a plurality of non-contact ribs are disposed alternately. The area (hereinafter referred to as the "rib area") and the area where the support is provided (hereinafter referred to as the "support area"). In this case, vacuuming of the second substrate in each of the respective pin regions (each rib region) is sequentially performed from the central portion of the main body portion toward the outer peripheral portion, whereby the second holding portion can be used The second substrate is adsorbed and held. Therefore, even if the second substrate is bent, the second holding portion can be appropriately held up to the outer peripheral portion of the second substrate, and the skew in the vertical direction of the joined superposed substrate can be suppressed.

Further, according to the present invention, a non-contact rib having a height lower than that of the support pin is provided on the outer peripheral portion of the body portion, and a so-called static pressure sealing method is employed. In other words, when the second holding portion vacuums the second substrate, the non-contact ribs do not contact the second substrate, and the support pins contact the second substrate, and the vacuum is applied to the rib region. The flow rate of the air is greater than the flow rate of the air evacuated in the support pin area. In this way, since the outer peripheral portion of the second substrate can be strongly evacuated, the outer peripheral portion can be appropriately held. Further, since the non-contact rib does not contact the second substrate, the contact area with the second substrate in the outer peripheral portion of the second holding portion can be made small, and the remaining portion of the outer portion of the second holding portion can be prevented from remaining on the outer surface of the second holding portion. There are cases of particles. Further, the second holding portion can be held flat until the outer peripheral portion of the second substrate. Therefore, in the bonding process, when the substrates are brought into contact with each other, the air between the substrates can be made to flow out to the outside, and the occurrence of the superposed substrates can be suppressed. The case of pores.

As described above, according to the present invention, it is possible to appropriately suppress the occurrence of the voids of the superposed substrate while suppressing the skew of the superposed substrate in the vertical direction, thereby appropriately performing the bonding process between the substrates.

The second holding portion may further include a contact rib, and the main body portion is concentrically provided in a ring shape on the inner side of the non-contact rib, and has the same height as the support pin, and the In the holding portion, the vacuuming of the second substrate can be set in each of the suction region on the inner side of the contact rib and the suction region on the outer side of the contact rib.

In the main body portion, a suction port for evacuating the outer peripheral portion of the second substrate may be formed in a region where the plurality of non-contact ribs are provided.

The main body portion may be divided into a plurality of pin supporting regions in a concentric region, and in the plurality of pin supporting regions, the interval of the plurality of pins of the inner pin supporting region is smaller than that of the outer pin region The interval between the foregoing plurality of pins.

The second holding portion may further include a temperature adjustment mechanism that adjusts a temperature of the second substrate held by the second holding portion. Further, the temperature adjustment mechanism may include a first temperature adjustment unit that adjusts a temperature of an outer peripheral portion of the second substrate, and a second temperature adjustment unit that performs a central portion of the outer side of the second substrate in the second substrate. Temperature adjustment.

The first holding portion may have another main body portion for evacuating the first substrate, and a plurality of other support pins provided on the other main body portion and in contact with the back surface of the first substrate; and a plurality of other portions The non-contact ribs are concentrically arranged in an annular shape in the outer peripheral portion of the other body portion, and have a lower height than the other support pins, and the plurality of adjacent non-contact ribs are provided with the aforementioned plurality Other sales.

According to another aspect of the invention, a joint system including the joint device includes: a processing station including the joint device; and a loading/unloading station that can store a plurality of first substrates and second a substrate or a superposed substrate in which the first substrate and the second substrate are joined together, and the first substrate, the second substrate, or the superposed substrate are carried in and out of the processing station, and the processing station includes a surface modification device to make the first substrate Or the surface of the second substrate to be bonded is modified; the surface hydrophilization device hydrophilizes the surface of the first substrate or the second substrate modified by the surface modification device; and the transfer device is adapted to change the surface The first device, the second substrate, or the superposed substrate are transported by the device, the surface hydrophilization device, and the bonding device. In the bonding device, the first substrate and the second substrate that are hydrophilized by the surface hydrophilization device are bonded to each other. .

According to another aspect of the invention, a bonding method for bonding substrates to each other by using a bonding apparatus, wherein the bonding apparatus has a first holding portion that vacuums a first substrate and is adsorbed and held underneath And the second holding portion is disposed below the first holding portion, and is vacuum-absorbed and held on the upper surface of the second substrate, wherein the second holding portion has a main body portion and vacuums the second substrate; a plurality of support pins are disposed on the main body portion and are in contact with the back surface of the second substrate; and the plurality of non-contact rib plates are concentrically arranged in a ring shape and lower in height in the outer peripheral portion of the main body portion The aforementioned support pin, adjacent to the aforementioned non- The plurality of support pins are provided between the contact ribs, and the bonding method includes a first holding process, and the first substrate is vacuumed and held by the first holding portion; the second holding process By the second holding portion, the second substrate is sequentially vacuumed and held from the center portion toward the outer peripheral portion, and the bonding process, and thereafter, the first substrate held by the first holding portion and held The second substrate of the second holding portion is disposed to face each other and joined to each other.

The second holding portion may further include a contact rib, and the main body portion is concentrically provided in a ring shape on the inner side of the non-contact rib, and has the same height as the support pin, and the The holding portion is configured to set a vacuum of the second substrate in the suction region on the inner side of the contact rib and the suction region on the outer side of the contact rib, and in the second holding process, the suction region on the inner side After the second substrate is adsorbed, the second substrate is adsorbed on the outer suction region.

In the second holding process, the outer peripheral portion of the second substrate may be evacuated from the suction port formed in the region where the plurality of non-contact ribs are provided in the main body portion.

The main body portion may be divided into a plurality of pin supporting regions in a concentric region, and in the plurality of pin supporting regions, the interval of the plurality of pins of the inner pin supporting region is smaller than that of the outer pin region In the bonding process, the first holding portion is stopped after the center portion of the first substrate and the inner pin region of the second substrate are pressed against each other in the bonding process. The vacuum is applied to the first substrate, and the first substrate and the first substrate are sequentially bonded from the central portion of the first substrate toward the outer peripheral portion. 2 substrates.

In the above-described bonding process, the temperature of the second substrate can be adjusted by the temperature adjustment mechanism provided in the second holding portion, and the first substrate and the second substrate can be joined. Further, the temperature adjustment mechanism may include a first temperature adjustment unit that adjusts a temperature of an outer peripheral portion of the second substrate, and a second temperature adjustment unit that performs a central portion of the outer side of the second substrate in the second substrate. In the temperature adjustment, in the bonding process, the set temperature of the first temperature adjustment unit is higher than the set temperature of the second temperature adjustment unit.

The first holding portion may have another body portion that evacuates the first substrate, and a plurality of other pins that are disposed on the other body portion and that are in contact with the back surface of the first substrate; and a plurality of other non- The contact ribs are concentrically arranged in an annular shape in the outer peripheral portion of the other body portion, and have a lower height than the other support pins, and the plurality of the other non-contact ribs are adjacent to each other. In the first holding process, the first holding portion is configured to evacuate and hold the first substrate from the center portion toward the outer peripheral portion by the first holding portion.

Further, according to another aspect of the invention, there is provided a program for operating on a computer that controls a control portion of the engagement device such that the engagement method is performed by the engagement device.

Moreover, according to another aspect of the present invention, a readable computer memory medium storing the aforementioned program is provided.

According to the present invention, it is possible to appropriately suppress the occurrence of the voids of the superposed substrate while suppressing the occurrence of the voids in the superposed substrate while suppressing the vertical direction of the superposed substrate so as to appropriately hold the substrate when the substrates are bonded to each other.

1‧‧‧ joint system

2‧‧‧ moving into and out of the station

3‧‧‧ Processing station

30‧‧‧Surface modification device

40‧‧‧ Surface Hydrophilization Unit

41‧‧‧Joining device

61‧‧‧ wafer transfer device

70‧‧‧Control Department

140‧‧‧Upper chuck

141‧‧‧ lower chuck

170‧‧‧ Body Department

171‧‧ ‧ sales

190‧‧‧ Body Department

191‧‧ ‧ sales

192‧‧‧Contact ribs

193~196‧‧‧ Non-contact ribs

197a‧‧‧1st attraction area

197b‧‧‧2nd attraction area

197c‧‧‧3rd attraction area

197d‧‧‧4th attraction area

197e‧‧‧5th attraction area

300‧‧‧1st sales area

301‧‧‧2nd sales area

310‧‧‧1st sales area

311‧‧‧2nd sales area

312‧‧‧3rd sales area

320‧‧‧temperature adjustment mechanism

330‧‧‧ Temperature adjustment mechanism

331‧‧‧1st temperature adjustment department

332‧‧‧2nd temperature adjustment department

340‧‧‧3rd attraction

W _U ‧‧‧ Wafer

W _L ‧‧‧ under wafer

W _T ‧‧‧Cover wafer

Fig. 1 is a plan view showing the outline of the configuration of the joining system of the embodiment.

Fig. 2 is a side view showing the outline of the internal structure of the joining system of the embodiment.

FIG. 3 is a schematic side view showing the configuration of the upper wafer and the lower wafer.

Fig. 4 is a schematic cross-sectional view showing the configuration of the joining device.

Fig. 5 is a longitudinal cross-sectional view showing a schematic configuration of a joining device.

Fig. 6 is a schematic longitudinal cross-sectional view showing the configuration of an upper chuck and a lower chuck.

[Fig. 7] A plan view of the upper chuck viewed from below.

[Fig. 8] A plan view of the lower chuck viewed from above.

Fig. 9 is an explanatory view showing an enlarged portion of a lower chuck.

FIG. 10 is an explanatory view showing a state in which the outer peripheral portion of the lower wafer is adsorbed and held.

Fig. 11 is an explanatory view showing an enlarged outer peripheral portion of the lower chuck in the comparative example.

Fig. 12 is a flow chart showing the main construction of the wafer bonding process.

FIG. 13 is an explanatory view showing a state in which the lower wafer is adsorbed and held in the first suction region.

FIG. 14 is an explanatory view showing a state in which the lower wafer is adsorbed and held in the first to fifth suction regions.

FIG. 15 is an explanatory view showing a state in which the center portion of the upper wafer and the center portion of the lower wafer are pressed to abut.

FIG. 16 is an explanatory view showing a state in which the upper wafer is sequentially brought into contact with the lower wafer.

FIG. 17 is an explanatory view showing a state in which the surface of the upper wafer is brought into contact with the surface of the lower wafer.

FIG. 18 is an explanatory view showing a state in which the upper wafer and the lower wafer are joined.

Fig. 19 is a longitudinal cross-sectional view showing the outline of a chuck in another embodiment.

Fig. 20 is a plan view of the chuck in the other embodiment.

Fig. 21 is a plan view of the chuck in the other embodiment.

Fig. 22 is a longitudinal cross-sectional view showing the outline of a chuck in another embodiment.

Fig. 23 is a longitudinal cross-sectional view showing the outline of a chuck in another embodiment.

Fig. 24 is a longitudinal cross-sectional view showing the outline of a chuck in another embodiment.

Hereinafter, embodiments of the present invention will be described. Fig. 1 is a plan view showing the outline of the configuration of the joining system 1 of the present embodiment. Fig. 2 is a side view showing the outline of the internal structure of the joining device 1.

In the bonding system 1, as shown in FIG. 3, for example, wafers W _U and W _{L which are} two substrates are bonded. 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, the bonding surface on which the upper wafer W _U is bonded is referred to as "surface W _U1 ", and the surface on the opposite side to the surface W _U1 is referred to as "back surface W _U2 ". Similarly, the bonding surface on which the lower wafer W _L is bonded is referred to as "surface WL ₁ ", and the surface on the opposite side to the surface WL ₁ is referred to as "back surface WL ₂ ". Further, in the bonding system 1, the upper wafer W _U and the lower wafer W _L are bonded to form a superposed wafer W _T as a superposed substrate.

As shown in FIG. 1 , the joining system 1 has a configuration in which the loading/unloading station 2 and the processing station 3 are integrally connected, and the loading/unloading station 2 can carry a plurality of wafers W _U , for example, by loading and unloading between the outside and the outside. W _L , a plurality of cassettes C _U , C _L , C _T of the superposed wafer W _T , and the processing station 3 is provided with various processes for applying predetermined processing to the wafers W _U and W _L and the superposed wafers W _T Processing device.

The cassette loading and unloading station 2 is provided with a cassette mounting table 10. In the cassette mounting table 10, a plurality of, for example, four cassette mounting plates 11 are provided. The cassette mounting plate 11 is arranged in a line in the X direction (the vertical direction in FIG. 1) in the horizontal direction. When the cassettes C _U , C _L , and C _{T are} carried in and out of the joining system 1 , the cassettes C _U , C _L , and C _T can be placed on the cassette mounting plates 11 . In this manner, the loading/unloading station 2 is configured to store a plurality of upper wafers W _U , a plurality of lower wafers W _L , and a plurality of overlapping wafers W _T . Further, the number of the cassette mounting plates 11 is not limited to the embodiment, and can be arbitrarily set. Alternatively, one of the cassettes can be used as an abnormal wafer for recycling. That is, a cassette in which an abnormal wafer is bonded to the upper wafer W _U and the lower wafer W _L due to various reasons and separated from the other normal superposed wafers W _{T can be used} . In this embodiment aspect, the plurality of lines C _T cassette in a cassette C _T using as an abnormality with a wafer recovery, while the other cassettes C _T using the superposed wafer W as a normal _T for storage.

The loading/unloading station 2 is provided with the wafer transfer unit 20 adjacent to the cassette mounting table 10. The wafer transfer unit 20 is provided with a wafer transfer device 22 that is movably movable on a transfer path 21 extending in the X direction. The wafer transfer device 22 can also be moved in the vertical direction and around the vertical axis (θ direction), and the cassettes C _U , C _L , C _T on the cassette mounting plates 11 and the processing stations described later can be used. Between the transfer devices 50 and 51 of the third processing block G3 of 3, the wafers W _U and W _L and the superposed wafers W _{T are transferred} .

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

For example, in the first processing block G1, the surface _modification device 30 that reforms 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, under a reduced pressure environment, oxygen or nitrogen as a processing gas is excited to be plasmaized and ionized. The surface W _U1 and W _{L1 are} irradiated with the oxygen ions or nitrogen ions, and the surfaces W _U1 and W _L1 are plasma-treated to be modified.

For example, in the second processing block G2, the surface hydrophilization device 40 is arranged in the Y direction in the horizontal direction from the loading/unloading station 2 side, and the surfaces of the wafers W _U and W _L are made of, for example, pure water. W _U1 and W _{L1 are} hydrophilized, and the surfaces W _U1 and W _L1 are cleaned; and the bonding device 41 is bonded to the wafers W _U and W _L .

In the surface hydrophilization device 40, pure water is supplied to the wafers W _U and W _L while rotating the wafers W _U and W _L held in, for example, the spin chuck. As a result, the supplied pure water diffuses on the surfaces W _U1 and W _L1 of the wafers W _U and W _L , and the surfaces W _U1 and W _L1 are hydrophilized. In addition, the configuration of the joining device 41 will be described later.

For example, in the third processing block G3, as shown in FIG. 2, the wafers W _U and W _L and the transfer devices 50 and 51 of the superposed wafer W _{T are} sequentially provided in two layers from the bottom.

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

The wafer transfer device 61 has, for example, a transfer arm that is movable in the vertical direction, the horizontal direction (Y direction, the X direction), and the vertical axis. The wafer transfer device 61 is movable in the wafer transfer region 60, and transports the wafers W _U and W _L and the coincident wafer W _T to the surrounding first processing block G1 and the second processing block G2. The predetermined device in the third processing block G3.

In the above-described joint system 1, a control unit 70 is provided as shown in Fig. 1 . The control unit 70 is, for example, a computer and has a program storage unit (not shown). In the program storage unit, a program for controlling the processes of the wafers W _U and W _{L of the} bonding system 1 and the wafer W _T is stored. Further, in the program storage unit, a program for controlling the operation of the drive system such as the above-described various processing devices or transport devices to realize the wafer bonding process described later in the bonding system 1 is also stored. In addition, the aforementioned program may be readable by a computer such as a hard disk (HD), a floppy disk (FD), a compact disk (CD), a magneto-optical disk (MO), a memory card, or the like. The memory medium H is installed in the control unit 70 by the memory medium H.

Next, the configuration of the above-described joining device 41 will be described. As shown in FIG. 4, the joining device 41 has a processing container 100 that can be sealed inside. On the side surface of the processing container 100 on the side of the wafer transfer region 60, wafers W _U and W _L and a loading/unloading port 101 for the wafer W _T are formed, and a switching gate 102 is provided in the loading/unloading port 101.

The inside of the processing container 100 is partitioned into a transfer area T1 and a processing area T2 by the inner wall 103. The above-described loading/unloading port 101 is formed on the side surface of the processing container 100 in the transporting area T1. Further, on the inner wall 103, the wafers W _U and W _L and the loading/unloading ports 104 of the superposed wafers W _T are also formed.

In the positive direction of the X direction of the transport region T1, a transfer device 110 for temporarily placing the wafers W _U and W _L and superposing the wafer W _T is provided. The transfer device 110 is formed, for example, in two layers, and can simultaneously mount two of the wafers W _U and W _L and the superposed wafers W _T .

The wafer transfer mechanism 111 is provided in the transfer area T1. As shown in FIGS. 4 and 5, the wafer transfer mechanism 111 has, for example, a transfer arm that is movable in the vertical direction, the horizontal direction (Y direction, the X direction), and the vertical axis. Further, the wafer transfer mechanism 111 can transport the wafers W _U and W _L and the overlap wafer W _T in the transfer region T1 or between the transfer region T1 and the process region T2.

A position adjustment mechanism 120 that adjusts the orientation of the wafers W _U and W _{L in} the horizontal direction is provided on the negative side in the X direction of the conveyance region T1. The position adjustment mechanism 120 includes a base 121 including a holding portion (not shown) that holds and rotates the wafers W _U and W _L , and a detecting portion 122 that detects the grooves of the wafers W _U and W _L The position of the mouth. Further, in the position adjustment mechanism 120, while the wafers W _U and W _L held by the base 121 are rotated, the detection unit 122 detects the positions of the notches of the wafers W _U and W _L . The position of the notch portion is adjusted, and the orientation of the wafers W _U , W _{L in} the horizontal direction is adjusted. Further, the form in which the wafers W _U and W _L are held in the base 121 is not particularly limited, and various methods such as a pin chuck method or a rotary chuck method can be used.

Further, in the transport region T1, an inversion mechanism 130 that reverses the front and back surfaces of the upper wafer W _U is provided. The reversing mechanism 130 has a holding arm 131 that holds the upper wafer W _U . The holding arm 131 extends in the horizontal direction (Y direction). Further, in the holding arm 131, for example, holding members 132 that hold the upper wafer W _U are provided at four places.

The holding arm 131 is supported by a driving unit 133 including, for example, a motor. The arm 131 is held by the driving unit 133 so as to be rotatable about a horizontal axis. Further, the holding arm 131 is rotatable about the driving portion 133 and is movable in the horizontal direction (Y direction). Below the drive unit 133, another drive unit (not shown) including a motor or the like is provided. With the other driving portion, the driving portion 133 is movable in the vertical direction along the support column 134 (the support column extends in the vertical direction). In this manner, the upper wafer W _U held by the holding member 132 by the driving portion 133 can be rotated about the horizontal axis and can be moved in the vertical direction and the horizontal direction. Further, the upper wafer W _U held by the holding member 132 is rotated about the driving portion 133, and is movable between the position adjusting mechanism 120 and the upper chuck 140 which will be described later.

In the processing region T2, an upper chuck 140 is provided as a first holding portion for holding and holding the upper wafer W _U on the lower surface, and a lower chuck 141 for holding and holding the lower wafer W _L thereon. The second holding portion. The lower chuck 141 is disposed below the upper chuck 140 and is disposed to face the upper chuck 140. That is, the upper wafer W _U held by the upper chuck 140 and the lower wafer W _L held by the lower chuck 141 can be disposed opposite each other.

The upper chuck 140 is supported by the upper chuck support portion 150 (the upper chuck support portion is disposed above the upper chuck 140). The upper chuck support portion 150 is provided on the ceiling surface of the processing container 100. also That is, the upper chuck 140 is fixed to the processing container 100 via the upper chuck support portion 150.

The upper chuck support portion 150 is provided with an upper image pickup portion 151 that images the surface W _L1 of the wafer W _L held under the lower chuck 141. That is, the upper imaging unit 151 is disposed adjacent to the upper chuck 140. In the upper imaging unit 151, for example, a CCD camera is used.

The lower chuck 141 is supported by the first lower chuck moving portion 160 (the first lower chuck moving portion is provided below the lower chuck 141). The first lower chuck moving portion 160 is configured to move the lower chuck 141 in the horizontal direction (Y direction) as will be described later. Further, the first lower chuck moving portion 160 is configured such that the lower chuck 141 can be moved in the vertical direction and rotated about the vertical axis.

The lower lower chuck moving portion 160 is provided with a lower image capturing portion 161 that images the surface W _U1 of the wafer W _U held on the upper chuck 140. That is, the lower imaging unit 161 is provided adjacent to the lower chuck 141. For the lower imaging unit 161, for example, a CCD camera is used.

The first lower chuck moving portion 160 is attached to the pair of guide rails 162 and 162 (the guide rail is provided on the lower surface side of the first lower chuck moving portion 160 and extends in the horizontal direction (Y direction)). Further, the first lower chuck moving portion 160 is configured to be movable along the guide rail 162.

The pair of guide rails 162 and 162 are disposed on the second lower chuck moving portion 163. The second lower chuck moving portion 163 is attached to the pair of guide rails 164 and 164 (the guide rail is provided on the lower surface side of the second lower chuck moving portion 163 and extends in the horizontal direction (X direction)). And, the second The chuck moving portion 163 is configured to be movable along the guide rail 164, that is, to move the lower chuck 141 in the horizontal direction (X direction). Further, the pair of guide rails 164 and 164 are disposed on the mounting table 165 (the mounting table is provided on the bottom surface of the processing container 100).

Next, the detailed configuration of the chuck 140 and the lower chuck 141 on the joining device 41 will be described.

In the upper chuck 140, as shown in Figs. 6 and 7, a pin chuck method is employed. The upper chuck 140 has a body portion 170 (the body portion having a diameter at least greater than the upper wafer W _U in plan view). On the lower surface of the main body portion 170, a plurality of support pins 171 which are in contact with the back surface W _{U2 of the} upper wafer W _U are provided. Further, on the lower surface of the main body portion 170, an annular rib 172 is provided on the outer side of the plurality of support pins 171. The rib 172 supports the outer peripheral portion of the back surface W _{U2 so} as to support at least the outer edge portion of the back surface W _U2 of the upper wafer W _U .

Further, on the lower surface of the main body portion 170, other ribs 173 are provided inside the ribs 172. The ribs 173 are annularly arranged in a ring shape with the ribs 172. Further, a region 174 inside the rib 172 (hereinafter sometimes referred to as a suction region 174) is a first suction region 174a partitioned inside the rib 173 and a second suction region 174b on the outer side of the rib 173. .

On the lower surface of the main body portion 170, a first suction port 175a for evacuating the upper wafer W _U is formed in the first suction region 174a. The first suction port 175a is formed, for example, at two locations in the first suction region 174a. The first suction pipe 176a provided inside the main body portion 170 is connected to the first suction port 175a. Further, in the first suction pipe 176a, the first vacuum pump 177a is connected via a connection pipe.

Further, on the lower surface of the main body portion 170, a second suction port 175b for evacuating the upper wafer W _U is formed in the second suction region 174b. The second suction port 175b is formed in two places, for example, in the second suction region 174b. The second suction pipe 176b provided inside the main body portion 170 is connected to the second suction port 175b. Further, in the second suction pipe 176b, the second vacuum pump 177b is connected via a connection pipe.

In this manner, the upper chuck 140 is configured to evacuate the upper wafer W _U in the first suction region 174a and the second suction region 174b. Further, the arrangement of the suction ports 175a and 175b is not limited to the embodiment, and can be arbitrarily set.

Further, the suction regions 174a and 174b formed by the upper wafer W _U , the main body portion 170, and the ribs 172 are evacuated from the suction ports 175a and 175b, respectively, and the suction regions 174a and 174b are depressurized. At this time, since the environment outside the suction regions 174a and 174b is at atmospheric pressure, the upper wafer W _U is pressed against the suction regions 174a and 174b by the atmospheric pressure at a reduced pressure, and the upper wafer W _U is pressed. The adsorption is held on the upper chuck 140.

In this case, since the ribs 172, based on a back surface supporting the outer edge portion of the wafer W _U2 of W _U, therefore, the wafer W _U, Department suitably evacuated until the outer peripheral portion. Therefore, the entire wafer W _U is adsorbed and held on the upper chuck 140, and the flatness of the upper wafer W _U can be reduced, thereby flattening the upper wafer W _U .

Moreover, since the heights of the plurality of support pins 171 are equal, the flatness of the lower surface of the upper chuck 140 can be further reduced. In this way, the lower surface of the upper chuck 140 can be made flat (the lower flatness is reduced), and the skew in the vertical direction of the wafer W _U held on the upper chuck 140 can be suppressed.

Moreover, since the back surface W _{U2 of the} upper wafer W _U is supported by the plurality of support pins 171, when the vacuum of the wafer W _U is released by the upper chuck 140, the upper wafer W _U It becomes easy to peel off from the upper chuck 140.

In the upper chuck 140, a through hole 178 is formed in a central portion of the main body portion 170 (the through hole penetrates the main body portion 170 in the thickness direction). The central portion of the body portion 170 corresponds to a central portion of the wafer W _U that is adsorbed and held on the upper chuck 140. Further, a distal end portion of the actuator portion 181 of the push member 180 to be described later is inserted into the through hole 178.

On the upper surface of the upper chuck 140, a pushing member 180 that pushes the center portion of the upper wafer W _U is provided. The pushing member 180 has an actuator portion 181 and a cylinder portion 182.

Since the actuator unit 181 generates a constant pressure in a certain direction by the air supplied from the electro-pneumatic regulator (not shown), the pressure can be fixed regardless of the position of the action point of the pressure. produce. Further, by the air from the electro-pneumatic regulator, the actuator portion 181, the central unit may be controlled based on the wafer W _U abuts against the pressing load applied to the central portion of the upper wafer W _U. Further, the tip end portion of the actuator portion 181 is inserted into the through hole 178 by the air from the electro-pneumatic regulator, and is vertically movable in the vertical direction.

The actuator portion 181 is supported by the cylinder portion 182. The cylinder portion 182 is configured to move the actuator portion 181 in the vertical direction by a driving portion having a motor built therein.

As described above, the pushing member 180 controls the movement of the actuator portion 181 by the cylinder portion 182 by controlling the pressing load by the actuator portion 181. Further, the pushing member 180 can press the center portion of the upper wafer W _{U and} the center portion of the lower wafer W _L to be pressed when the wafers W _U and W _L described later are joined.

In the lower chuck 141, similarly to the upper chuck 140, as shown in Figs. 6, 8, and 9, a pin chuck method is employed. The lower chuck 141 has a body portion 190 (the body portion having a diameter at least larger than the lower wafer W _L in plan view). On the upper surface of the main body portion 190, a plurality of support pins 191 that are in contact with the back surface W _L2 of the lower wafer W _{L are provided} .

On the upper surface of the body portion 190, annular ribs 192 to 196 are provided. The ribs 192 to 196 are concentrically arranged with the main body portion 190, and are disposed in order from the central portion of the main body portion 190 toward the outer peripheral portion. The rib 192 (hereinafter sometimes referred to as a contact rib 192) provided at the center of the main body portion 190 has the same height as the support pin 191 and is in contact with the back surface W _{L2 of the} lower wafer W _L . The ribs 193 to 196 (hereinafter sometimes referred to as non-contact ribs 193 to 196) provided on the outer peripheral portion of the main body portion 190 have a lower height than the support pin 191 and do not overlap with the lower wafer W _L The back W _L2 contacts. Further, a plurality of support pins 191 are provided between the adjacent ribs 192 to 196. Further, the number of the non-contact ribs is not limited to the embodiment, and can be arbitrarily set.

On the upper surface of the body portion 190, a region 197 (hereinafter sometimes referred to as a suction region 197) inside the rib 196 is partitioned into ribs 192 to 196. That is, the suction region 197 is partitioned into: a first suction region 197a contacting the inside of the rib 192; a second suction region 197b between the contact rib 192 and the non-contact rib 193; and non-contact ribs 193, 194 The third suction region 197c; the fourth suction region 197d between the non-contact ribs 194 and 195; and the fifth suction region 197e between the non-contact ribs 195 and 196.

On the upper surface of the main body portion 190, a first suction port 198a for evacuating the lower wafer W _L is formed in the first suction region 197a. The first suction port 198a is formed, for example, at two locations in the first suction region 197a. The first suction pipe 199a provided inside the main body portion 190 is connected to the first suction port 198a. Further, in the first suction pipe 199a, the first vacuum pump 200a is connected via a connection pipe.

Further, on the upper surface of the main body portion 190, a second suction port 198b for evacuating the lower wafer WL is formed in the suction regions 197b to 197e. The second suction port 198b is formed in two places, for example, in the second suction region 197b. The second suction pipe 199b provided inside the main body portion 190 is connected to the second suction port 198b. Further, in the second suction pipe 199b, the second vacuum pump 200b is connected via a connection pipe.

Further, the arrangement of the suction ports 198a and 198b is not limited to the embodiment, and can be arbitrarily set. For example, the second suction port 198b, Although the suction regions 197b to 197e are provided in common, the suction ports may be provided in the respective suction regions 197b to 197e. In this way, an embodiment in which the suction ports are provided in the suction regions 197b to 197e will be described later.

Then, the suction regions 197a to 197e are evacuated from the suction ports 198a and 198b, and the suction regions 197a to 197e are depressurized. At this time, since the environment outside the suction regions 197a to 197e is at atmospheric pressure, the lower wafer W _L is pressed toward the suction regions 197a to 197e by the atmospheric pressure at a reduced pressure, and the lower wafer W _L is pressed. The adsorption is held by the lower chuck 141.

Here, the holding of the outer peripheral portion of the wafer W _L below the suction regions 197c to 197e will be described in detail.

Since the suction regions 197c to 197e are separated by the non-contact ribs 193 to 196, when the vacuum is started from the second suction port 198b, the second suction port 198b is sequentially, that is, The order of the suction regions 197c to 197e is evacuated. As a result, as shown in FIG. 10, the lower wafer W _L is sequentially adsorbed and held from the inner side toward the outer side. Thus, for example, even in the general state, the outside circumferential portion of the wafer W _L is bent vertically upward, the lower chuck 141, line _L can be appropriately held in the lower outer peripheral portion of the wafer W up.

Further, in the suction regions 197c to 197e, the lower wafer W _L is adsorbed and held by a so-called static pressure seal. When the lower wafer W _L is evacuated from the second suction port 198b, the flow rate of the air sucked in the portion (rib region) where the non-contact ribs 193 to 196 are provided is larger than that which is not provided. The portion (the pin area) of the non-contact ribs 193 to 196. In this way, it is possible to appropriately evacuate the outer peripheral portion of the lower wafer W _{L with a} stronger force than the center portion.

Fig. 11 shows a comparative example with respect to the present embodiment. For example, when the rib R on the outer circumference of the main body portion 190 is in contact with the back surface W _{L2 of the} lower wafer W _L and is disposed further inside than the outer edge portion, the lower chuck W is adsorbed and held by the lower chuck 141. _{In the case of L} , the outer peripheral portion of the lower wafer W _L is bent vertically upward with the rib R as a starting point.

On the other hand, in the present embodiment, as described above, since the lower wafer W _L can be appropriately evacuated to the outer peripheral portion in the suction regions 197c to 197e, the entire wafer W _L is completely covered. The adsorption is held by the lower chuck 141, and the flatness of the lower wafer W _L can be reduced, thereby flattening the lower wafer W _L .

Moreover, since the heights of the plurality of support pins 191 are equal, the flatness of the upper surface of the lower chuck 141 can be further reduced. Therefore, the flatness of the wafer W _L held under the lower chuck 141 can be further reduced, and the skew of the vertical direction of the lower wafer W _L can be suppressed.

Further, since the back surface of the wafer W _L W _L2, the train is supported on a plurality of support pins 191, and therefore, the lower chuck of the wafer W _L evacuated occasion of releasing the vacuum under 141 due to the lower wafer W _L It will become easy to peel off from the lower chuck 141.

As shown in FIG. 8, in the lower chuck 141, a through hole 201 (which penetrates the main body portion 190 in the thickness direction) is formed in three places in the vicinity of the center portion of the main body portion 190, for example. Further, the lift pin provided below the first lower chuck moving portion 160 is inserted through the through hole 201.

A guide member 202 is provided on the outer peripheral portion of the main body portion 190 (the guide member prevents the wafers W _U , W _L and the superposed wafers W _T from flying out or falling off from the lower chuck 141 ). The guiding members 202 are attached to the outer peripheral portion of the body portion 190 at a plurality of places, for example, four places at equal intervals.

Further, the operation of each unit of the joining device 41 is controlled by the above-described control unit 70.

Next, a bonding processing method using the wafers W _U and W _L by the bonding system 1 configured as described above will be described. Fig. 12 is a flow chart showing an example of the main construction of the wafer bonding process.

First, a plurality of pieces accommodated in the wafer cassette C _U W _U is accommodated at a plurality of pieces of wafer cassettes W _L C _L and an empty cassette C _T, it is placed on a predetermined line loading and unloading of the station 2 The cassette is placed on the board 11. Thereafter, the wafer transfer unit 22 takes out the upper wafer W _{U in the} cassette C _U and transports it to the transfer device 50 of the third processing block G3 of the processing station 3.

Next, the upper wafer W _U is transported to the surface modification device 30 of the first processing block G1 by the wafer transfer device 61. In the surface reforming device 30, oxygen and nitrogen as a processing gas are excited to be plasma-formed and ionized in a predetermined reduced pressure environment. The oxygen ions or nitrogen ions are irradiated onto the surface W _{U1 of the} upper wafer W _U such that the surface W _U1 is plasma treated. Moreover, the surface W _{U1 of the} upper wafer W _U is modified (engineering S1 of Fig. 12).

Next, the upper wafer W _U is transported to the surface hydrophilization device 40 of the second processing block G2 by the wafer transfer device 61. In the surface hydrophilization device 40, pure water is supplied onto the upper wafer W _U while rotating the upper wafer W _U held by the spin chuck. In this way, the supplied pure water is diffused on the surface W _U1 of the upper wafer W _U , and the hydroxyl group (sterol group) is attached to the wafer W _U which has been modified in the surface modification device 30 . surface W _U1, W _U1 so that the surface hydrophilic. Further, the surface W _{U1 of the} upper wafer W _U is cleaned by the pure water (the project S2 of Fig. 12).

Next, the upper wafer W _U is transported to the bonding apparatus 41 of the second processing block G2 by the wafer transfer device 61. The upper wafer W _{U carried} into the bonding apparatus 41 is transported to the position adjusting mechanism 120 by the wafer transfer mechanism 111 via the transfer device 110. Further, the position adjustment mechanism 120 adjusts the orientation of the upper wafer W _{U in} the horizontal direction (the construction S3 of Fig. 12).

Thereafter, the upper wafer W _U is taken from the position adjusting mechanism 120 to the holding arm 131 of the reversing mechanism 130. Next, in the transfer region T1, the front and back surfaces of the upper wafer W _U are reversed so that the holding arm 131 is reversed (the process S4 in Fig. 12). That is, the surface W _{U1 of the} upper wafer W _U faces downward.

Thereafter, the holding arm 131 of the reversing mechanism 130 is rotated about the driving portion 133 and moved to the lower side of the upper chuck 140. Further, the upper wafer W _U is received from the reversing mechanism 130 to the upper chuck 140. The upper wafer W _U is adsorbed and held by the upper surface W _U2 on the upper chuck 140 (engineering S5 of Fig. 12). Specifically, the vacuum pump 177a, 177b actuated in the suction area 174a, 174b in via the suction port 175a, 175b, on the wafer W _U evacuated, the wafer W _U will be held on the suction chuck 140.

During the wafer W _U of the processing of the above-described construction of the S1 ~ S5, the connection at the wafer W _L immediately after the treatment on the wafer W _U. First, the lower wafer W _{L in the} cassette C _L is taken out by the wafer transfer device 22 and transported to the transfer device 50 of the processing station 3.

Next, the lower wafer W _L is transported to the surface modification device 30 by the wafer transfer device 61, and the surface W _{L1 of the} lower wafer W _L is modified (the process S6 of FIG. 12). Further, the modification of the surface W _L1 of the wafer W _L in the lower portion of the process S6 is the same as the above-described project S1.

Thereafter, the lower wafer W _L is transported to the surface hydrophilization device 40 by the wafer transfer device 61, and the surface W _{L1 of the} lower wafer W _L is hydrophilized while washing the surface W _L1 (Fig. 12 Engineering S7). Further, the hydrophilization and washing of the surface W _L1 of the wafer W _L in the lower portion of the process S7 is the same as the above-described project S2.

Thereafter, the lower wafer W _L is transported to the bonding apparatus 41 by the wafer transfer device 61. The lower wafer W _L carried into the bonding apparatus 41 is transported to the position adjusting mechanism 120 by the wafer transfer mechanism 111 via the transfer device 110. Further, the position of the lower wafer W _{L in} the horizontal direction is adjusted by the position adjusting mechanism 120 (the construction S8 of Fig. 12).

Thereafter, the lower wafer W _L is transported to the lower chuck 141 by the wafer transfer mechanism 111, and the back surface W _L2 is adsorbed and held by the lower chuck 141 (item S9 of FIG. 12). Further, in the present embodiment, the lower wafer W _L before being adsorbed and held by the lower chuck 141 is bent as shown in FIG.

In the first step S9, the first vacuum pump 200a is actuated, and as shown in FIG. 13, the lower wafer W _L is evacuated from the first suction port 198a in the first suction region 197a. In this way, the position of the lower wafer W _{L in} the horizontal direction is fixed.

Then, in a state where the first vacuum pump 200a is actuated, the second vacuum pump 200b is further actuated, and as shown in Fig. 14, the lower wafer W _L is sucked from the suction ports 198a and 198b in the suction regions 197a to 197e. vacuum. At this time, when vacuuming is started from the second suction port 198b, the second suction port 198b is sequentially evacuated in the order of the suction regions 197c to 197e, as shown in FIG. W _L is sequentially adsorbed and held from the inner side toward the outer side. Thus, for example, even in the general state, the outside circumferential portion of the wafer W _L is bent vertically upward, the wafer W _L is also suitably maintained until the outer peripheral portion. As a result, the lower wafer W _L is completely adsorbed and held by the lower chuck 141.

Next, the position adjustment of the wafer W _U held on the upper chuck 140 and the horizontal direction of the wafer W _L held under the lower chuck 141 is performed. Specifically, the lower chuck 141 is moved in the horizontal direction (X direction and the Y direction) by the first lower chuck moving portion 160 and the second lower chuck moving portion 163, and the upper imaging unit 151 is used. The predetermined reference points on the surface W _L1 of the lower wafer W _L are sequentially photographed. Simultaneously, the lower imaging unit 161 is used to sequentially photograph the predetermined reference points on the surface W _U1 of the upper wafer W _U . The captured image is output to the control unit 70. The control unit 70 is based on the image captured by the upper imaging unit 151 and the image captured by the lower imaging unit 161 by the first lower chuck moving unit 160 and the second lower chuck moving unit 163. The lower chuck 141 is moved to a position where the reference point of the upper wafer W _U coincides with the reference point of the lower wafer W _L . In this way, the horizontal position of the upper wafer W _U and the lower wafer W _L is adjusted (the construction S10 of FIG. 12).

Thereafter, the lower chuck 141 is moved vertically upward by the first lower chuck moving portion 160, and the vertical position of the upper chuck 140 and the lower chuck 141 is adjusted, and is held by the upper chuck 140. The upper wafer W _U is adjusted in the vertical direction of the wafer W _L held under the lower chuck 141 (the construction S11 of Fig. 12).

Next, the bonding process of the wafer W _U held on the upper chuck 140 and the wafer W _L held under the lower chuck 141 is performed.

First, as shown in FIG. 15, the actuator portion 181 is lowered by pushing the cylinder portion 182 of the member 180. As a result, as the actuator portion 181 descends, the center portion of the upper wafer W _U is pressed and lowered. At this time, a predetermined pressing load is applied to the actuator portion 181 by the air supplied from the electric air conditioner. Then, by pushing the member 180, the center portion of the upper wafer W _U is brought into contact with the center portion of the lower wafer W _L to be pressed (the process S12 of FIG. 12). At this time, the operation of the first vacuum pump 177a is stopped, the evacuation of the wafer W _U from the first suction port 175a of the first suction region 174a is stopped, and the second vacuum pump 177b is kept in operation, from the second suction port 175b. The second suction region 174b is evacuated. Further, also in the central portion of the occasion to push the pressing member 180 on the wafer W _U, and by the outer peripheral portion of the chuck 140 holding the wafer W _U.

As a result, bonding is started between the center portion of the wafer W _{U and} the center portion of the lower wafer W _L (the thick line portion in FIG. 12). 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 the works S1 and S6, respectively, first, between the surfaces W _U1 and W _L1 The van der Waals force (intermolecular force) is generated, and the surfaces W _U1 and W _L1 are joined to each other. Moreover, 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 the works S2 and S7, respectively, the hydrophilic groups between the surfaces W _U1 and W _L1 are mutually hydrogenated. Bonding (intermolecular force), the surfaces W _U1 and W _L1 are firmly joined to each other.

Thereafter, as shown in FIG. 16, when the center portion of the upper wafer W _{U and} the center portion of the lower wafer W _{L are} pressed by the pushing member 180, the operation of the second vacuum pump 177b is stopped, and the operation is stopped. 2 The evacuation of the wafer W _U on the second suction tube 176b of the suction region 174b. As a result, 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 the plurality of support pins 171, the upper wafer is lifted when the upper wafer 140 causes the vacuum of the wafer W _U to be released. W _U becomes easily peeled off from the upper chuck 140. Moreover, the upper wafer W _U falls onto the lower wafer W _L and abuts, and the bonding between the van der Waals force and the hydrogen bonding between the surfaces W _U1 and W _L1 is sequentially expanded. . As a result, as shown in FIG. 17, the surface W _{U1 of the} upper wafer W _U and the surface W _{L1 of the} lower wafer W _L are completely abutted, and the upper wafer W _U and the lower wafer W _L are bonded to each other ( FIG. 12 Engineering S13).

In the case of the process S13, for example, when the outer peripheral portion of the lower wafer W _L is vertically upward, the distance between the outer peripheral portion of the upper wafer W _{U and the} outer peripheral portion of the lower wafer W _L becomes small. As a result, when the upper wafer W _U falls onto the lower wafer W _L , there is a case where the air between the wafers W _U and W _L cannot be completely formed in the outer peripheral portion thereof. The upper wafer W _U abuts on the lower wafer W _L before it flows out. In this case, the bonded coincident wafer W _T creates a void.

From this viewpoint, in this embodiment, lines such as the above figure, the disc 14 by the clamp 141 holding the wafer W _L suction Comprehensively, the wafer W _L lines until a flat outer circumferential portion. Further, in the adsorption chuck 140 also retaining the overall wafer W _U, W _U based on the wafer until a flat outer circumferential portion. Therefore, the air between the wafers W _U and W _L can be made to flow out to the outside, and the occurrence of voids in the coincident wafer W _{T can} be suppressed.

Thereafter, as shown in FIG. 18, the actuator portion 181 of the pushing member 180 is raised to the upper chuck 140. And, actuating the vacuum pump stops 200a, 200b, and stopping the suction region 197 below the wafer W is evacuated _{L, L} further adsorption chuck 141 pairs of holding the wafer W is stopped. At this time, since the back surface W _{L2 of the} lower wafer W _L is supported by the plurality of support pins 191, the lower wafer W is removed when the vacuum of the wafer W _L is released due to the lower chuck 141. _L becomes easy to peel off from the lower chuck 141.

The superposed wafer W _{T obtained} by bonding the upper wafer W _U and the lower wafer W _L is transported to the transfer device 51 by the wafer transfer device 61, and then transferred to the transfer device 2 by the wafer transfer device 22 is transported to the cassette C _{T of the} predetermined cassette mounting plate 11. As a result, the bonding process of the series of wafers W _U and W _L ends.

According to the above embodiment, a plurality of non-contact ribs 193 to 195 are provided on the outer peripheral portion of the main body portion 190, and a plurality of support pins 191 are provided between the adjacent non-contact ribs 193 to 195. Therefore, in the process S9, the vacuum of the wafer W _L under the suction regions 197c to 197e can be sequentially performed toward the outer peripheral portion of the main body portion 190, and the lower chuck can be sequentially adsorbed and held by the lower chuck 141. Round W _L . Therefore, even if the lower wafer W _{L is} bent, the lower chuck 141 can be appropriately held up to the outer periphery of the lower wafer W _L , and the skew in the vertical direction of the joined superposed substrate W _T can be suppressed.

Further, in the suction regions 197c to 197e, a so-called static pressure sealing method is employed. As described above, since the lower chuck 141 strongly draws the outer peripheral portion of the lower wafer W _L as described above, the outer peripheral portion can be appropriately held. Also, since the non-contact rib 193 to 195 does not contact at the back surface of the wafer W _L W _L2, therefore, the area of contact with the lower peripheral portion of the wafer W _L outside of the disc clamp 141 can be reduced and suppressed in A case where fine particles remain on the outer peripheral portion of the lower chuck 141. Moreover, the lower chuck 141 can be held flat until the outer periphery of the lower wafer W _L . Therefore, in the case of the process S13, when the wafers W _U and W _L are brought into contact with each other, the air between the wafers W _U and W _L can flow out to the outside, and the occurrence of voids in the superposed substrate W _{T can} be suppressed.

As described above, according to the present embodiment, the skew can be suppressed while the vertical direction coincides W _T of the substrate, while suppressing the generation of voids is coincident W _T of the substrate, and the wafer appropriately W _U, W _L of each other bonding process.

Further, since the lower chuck 141 is partitioned into the first suction region 197a and the suction regions 197b to 197e on the outer side by the contact ribs 192, the following chucks 141 can be held in two stages in the step S9. Lower wafer W _L . In other words, first, the lower wafer W _L is evacuated in the first suction region 197a, and the position of the lower wafer W _{L in} the horizontal direction is fixed. Therefore, the suction regions 197a to 197e are placed next. When the wafer W _L is evacuated, the position of the lower wafer W _{L in} the horizontal direction does not occur. Therefore, the lower wafer W _L can be adsorbed and held at an appropriate position of the lower chuck 141.

In addition, the upper wafer W _U and the lower wafer W _L may be any of the component wafer and the supporting wafer. The component wafer refers to a semiconductor wafer to be a product, and for example, an element having a plurality of electronic circuits or the like is formed on the surface thereof. Further, the support wafer refers to a wafer supporting the wafer of the element, and no component is formed on the surface thereof. Furthermore, the present invention can also be applied to any of the bonding process of the component wafer and the supporting wafer and the bonding process of the component wafers. However, when the element wafers are bonded to each other, in order to appropriately function the bonded wafer W _T as a product after the bonding, it is necessary to appropriately make the electronic circuit of the upper wafer W _U and the lower wafer W _L Corresponding. Therefore, as described above, adjusting the position of the upper wafer W _U and the lower wafer W _{L in} the horizontal direction is particularly suitable for the bonding process of the element wafers.

Further, in the bonding system 1 of the present embodiment, in addition to the bonding device 41, the surface modifying device 30 and the surface W _{U1 for} modifying the surfaces W _U1 and W _{L1 of} the wafers W _U and W _{L are provided} . The surface hydrophilization device 40 in which the W _{L1 is} hydrophilized and the surfaces W _U1 and W _{L1 are} washed, so that the bonding of the wafers W _U and W _L can be efficiently performed in one system. Therefore, the productivity of the wafer bonding process can be further improved.

Next, another embodiment of the lower chuck 141 in the bonding apparatus 41 of the above-described embodiment will be described.

As shown in FIGS. 19 and 20, the main body portion 190 of the lower chuck 141 may be partitioned into the first branch pin region 300 and the second branch pin region 301 according to the density of the support pins 191. The first pin region 300 is formed in a circular shape at the center portion of the body portion 190. The second branch pin region 301 is outside the first branch pin region 300, and is annularly arranged in a concentric shape with the first branch pin region 300. Further, the interval between the support pins 191 provided in the first branch pin region 300 is smaller than the interval between the support pins 191 provided in the second branch pin region 301.

As described above, in the step S12, the center portion of the upper wafer W _{U and} the center portion of the lower wafer W _L (the first branch pin region 300) are pressed by the pushing member 180. As a result, the center portion of the lower wafer W _L is skewed vertically downward due to the pressing load. Therefore, as shown in FIG. 19, the vertical direction of the lower portion of the lower wafer W _L can be suppressed by reducing the interval between the support pins 191 of the first branch pin region 300.

Further, as shown in FIG. 21, the main body portion 190 of the lower chuck 141 may be partitioned into the first branch pin region 310, the second branch pin region 311, and the third branch according to the density of the support pins 191. Three of the pin areas 312. The first branch pin area 310, the second branch pin area 311, and the third branch pin area 312 are arranged in a concentric manner from the center portion toward the outer peripheral portion. Further, the interval between the support pins 191 provided in the first branch pin region 310 is smaller than the interval between the support pins 191 provided in the second branch pin region 311. Further, the interval between the support pins 191 provided in the second branch pin region 311 is smaller than the interval between the support pins 191 provided in the third branch pin region 312. In this manner, the contact area of the wafer W _L supported under the lower chuck 141 can be smoothly changed so as to gradually increase the interval between the support pins 191 from the center portion toward the outer peripheral portion, and the lowering of the contact area can be suppressed. The vertical direction of the center portion of the wafer W _L is skewed, and the lower chuck 141 is used to more appropriately hold the lower wafer W _L . In addition, the number of the support pin area is not limited to this embodiment, and can be arbitrarily set. If the number of divisions is larger, the above effects can be more significantly enjoyed.

Further, as shown in FIG. 22, the lower chuck 141 may have a temperature adjustment mechanism 320 that adjusts the temperature of the wafer W _L held under the lower chuck 141. The temperature adjustment mechanism 320 is built in, for example, the body portion 190. Further, in the temperature adjustment mechanism 320, for example, a heater is used. In this case, the lower wafer W _{L is} heated by the temperature adjustment mechanism 320 to a predetermined temperature, for example, normal temperature (23 ° C) to 100 ° C, whereby the wafer W _U can be eliminated while performing the above-described process S13. The air between W _L. Therefore, the generation of the voids of the coincident wafer W _T can be more surely suppressed.

Further, as shown in FIG. 23, the temperature adjustment mechanism 330 of the lower chuck 141 may have the first temperature adjustment unit 331 and the second temperature adjustment unit 332. The first temperature adjustment unit 331 performs temperature adjustment of the outer peripheral portion of the lower wafer W _L and is built in, for example, the outer peripheral portion of the main body portion 190. Further, for example, a heater is used in the first temperature adjustment unit 331. The second temperature adjustment unit 332 performs temperature adjustment of the central portion inside the outer peripheral portion of the lower wafer W _L and is built in, for example, a central portion of the main body portion 190. In addition, the second temperature adjustment unit 332 is, for example, a flow path through which a cooling medium such as temperature-regulating water flows. In addition, the installation place or wiring of the first temperature adjustment unit 331 and the second temperature adjustment unit 332 may be arbitrarily designed, and the first temperature adjustment unit 331 and the second temperature adjustment unit 332 may be attached to, for example, the main body unit. Outside of 190.

Here, since the peripheral portions of the wafers W _U and W _L are exposed to the external environment, the temperature is more likely to fall than the central portion. Therefore, the set temperature of the first temperature adjustment unit 331 and the set temperature of the second temperature adjustment unit 332 are raised. For example, the set temperature of the second temperature adjustment unit 332 is set to normal temperature (23 ° C), and the set temperature of the first temperature adjustment unit 331 is set to be higher than normal temperature. Thereby, the temperature of the lower wafer W _L can be uniformly adjusted in the plane. Therefore, when the above-described process S13 is performed, the air between the wafers W _U and W _L can be eliminated, and the generation of the voids of the superposed wafer W _T can be more reliably suppressed. Moreover, the skew in the vertical direction of the joined coincident wafer W _T can be more reliably suppressed.

Further, as shown in FIG. 24, a third suction port 340 may be further formed on the upper surface of the main body portion 190 of the lower chuck 141. The third suction port 340 is formed, for example, at two places in the fifth suction region 197e between the non-contact ribs 195 and 196. The third suction pipe 341 provided inside the main body portion 190 is connected to the third suction port 340. Further, in the third suction pipe 341, the third vacuum pump 342 is connected via a connection pipe. In addition, the third suction port 340 is provided with a non-contact rib plate. It may be formed in the region of 193 to 196, and may be formed, for example, in the third suction region 197c or the fourth suction region 197d. Further, the third suction ports 340 may be formed in the suction regions 197c to 197e, respectively.

In this case, in the fifth suction region 197e, the outer peripheral portion of the lower wafer W _L is evacuated from the third suction port 340 in the fifth suction region 197e. That is, the outer peripheral portion of the lower wafer W _L is adsorbed and held by the static pressure sealing, and the third suction port 340 is also actively evacuated. Moreover, the degree of vacuum of the fifth suction region 197e can be increased. Therefore, the lower chuck 141 can appropriately hold the outer peripheral portion of the lower wafer W _L with a stronger force, and can more reliably suppress the skew of the vertical direction of the joined coincident wafer W _T . .

Further, the configuration of the lower chuck 141 described above can also be applied to the upper chuck 140. For example, in the upper chuck 140, the configuration of the lower chuck 141 as shown in Fig. 6 can be applied. That is, in the upper chuck 140, the same contact ribs as the contact ribs 192 are provided at the center portion thereof, and the same non-contact ribs as the non-contact ribs 193 to 196 are provided on the outer peripheral portion. In this case, when the above-described process S5 is performed, the upper chuck 140 is sequentially evacuated from the center portion toward the outer peripheral portion, and the upper wafer W _U is guided from the center portion toward the outer peripheral portion. The adsorption is maintained. Further, the upper chuck 140 can appropriately adsorb and hold the outer peripheral portion of the upper wafer W _U by static pressure sealing.

Further, the front end position of the support pin 171 provided at the center portion of the upper chuck 140 may be located lower than the front end position of the support pin 171 provided at the outer peripheral portion, that is, below the main body portion 170. It can have a convex shape below. In this case, in the upper chuck 140, the upper wafer W _U is protruded downward and held. Therefore, in the item S12, when the center portion of the upper wafer W _U is pressed by the pushing member 180, the amount of pressing can be reduced.

Further, in the upper chuck 140, other configurations of the lower chuck 141 can also be applied. That is, the configuration of the lower chuck 141 shown in Figs. 19 to 24 can also be applied to the upper chuck 140.

In addition, the upper chuck 140 may be a non-pin chuck type, and may take various forms such as a vacuum chuck method or an electrostatic chuck method by a flat chuck.

In the bonding apparatus 41 of the above-described embodiment, the upper chuck 140 is fixed to the processing container 100, and the lower chuck 141 is moved in the horizontal direction and the vertical direction. Alternatively, the upper chuck 140 may be horizontally reversed. The direction and the vertical direction are moved, and the lower chuck 141 is fixed to the processing container 100. However, since the moving mechanism of the upper chuck 140 is large, it is preferable to fix the upper chuck 140 to the processing container 100 as in the above embodiment.

In the bonding system 1 of the above-described embodiment, after the wafers W _U and W _{L are} bonded by the bonding apparatus 41, the bonded superposed wafers W _T may be further heated (annealed) at a predetermined temperature. By performing the heat treatment on the superposed wafer W _T , the joint interface can be more firmly bonded.

Hereinabove, the preferred embodiments of the present invention have been described with reference to the accompanying drawings, but the present invention is not limited to the examples. As long as it is a person with ordinary knowledge in the technical field, the ideas described in the scope of patent application can be applied. In view of the foregoing, it is obvious that various modifications and alterations are obvious, and it is understood that those skilled in the art are also within the scope of the invention. The present invention is not limited to this example, and various aspects can be employed. The present invention can also be applied to a case where the substrate is an FPD (flat panel display) other than the wafer, or another substrate such as a mask original for a mask.

140‧‧‧Upper chuck

141‧‧‧ lower chuck

170‧‧‧ Body Department

171‧‧ ‧ sales

172‧‧‧ ribs

173‧‧‧ Ribs

174a‧‧‧1st attraction area

174b‧‧‧2nd attraction area

175a‧‧‧1st attraction

175b‧‧‧2nd attraction

176a‧‧‧1st suction tube

176b‧‧‧2nd suction tube

177a‧‧‧1st vacuum pump

177b‧‧‧2nd vacuum pump

178‧‧‧through holes

180‧‧‧Promoting components

181‧‧‧Activity Department

182‧‧‧Cylinder Department

190‧‧‧ Body Department

191‧‧ ‧ sales

192‧‧‧Contact ribs

193‧‧‧ Non-contact ribs

194‧‧‧ Non-contact ribs

195‧‧‧ Non-contact ribs

196‧‧‧ Non-contact ribs

197a‧‧‧1st attraction area

197b‧‧‧Attraction area

198a‧‧‧ attracting mouth

198b‧‧‧ attracting mouth

199a‧‧‧1st suction tube

199b‧‧‧2nd suction tube

200a‧‧‧1st vacuum pump

200b‧‧‧2nd vacuum pump

W _U ‧‧‧ Wafer

W _L ‧‧‧ under wafer

Claims (16)

A bonding apparatus is a bonding apparatus for bonding substrates, characterized in that: a first holding portion that vacuum-absorbs a first substrate and is held by a lower surface; and a second holding portion that is provided in the first holding portion The second substrate is vacuumed and adsorbed and held on the upper surface, and the second holding portion has a main body portion that evacuates the second substrate, and a plurality of support pins are provided on the main body portion and are in contact with the first portion. a back surface of the substrate; and a plurality of non-contact ribs, which are concentrically arranged in a ring shape in a peripheral portion of the body portion, and have a height lower than the support pins, between the adjacent non-contact ribs, The foregoing plurality of pins are provided. The joining device according to claim 1, wherein the second holding portion further includes a contact rib, and the main body portion is concentrically provided in a ring shape inside the non-contact rib The height is the same as that of the support pin, and the second holding portion can set the vacuum of the second substrate in the suction region on the inner side of the contact rib and the suction region on the outer side of the contact rib. The joining device of claim 1 or 2, wherein in the body portion, the plurality of non-contact ribs are provided A suction port for evacuating the outer peripheral portion of the second substrate is formed in the region. The joining device of claim 1 or 2, wherein the body portion is concentrically divided into a plurality of branching pin regions, and in the plurality of pin supporting regions, the plurality of the inner pin supporting regions The interval between the pins is smaller than the interval between the plurality of pins of the outer pin area. The joining device according to claim 1 or 2, wherein the second holding portion further includes a temperature adjusting mechanism that adjusts a temperature of the second substrate held by the second holding portion. The bonding apparatus according to claim 5, wherein the temperature adjustment mechanism includes: a first temperature adjustment unit that adjusts a temperature of a peripheral portion of the second substrate; and a second temperature adjustment unit that is in the second substrate The temperature is adjusted at the central portion of the inner side of the outer circumference. The bonding device according to claim 1 or 2, wherein the first holding portion has another body portion that evacuates the first substrate, and the plurality of other pins are provided on the other body portion, and Contacting the back surface of the first substrate; and the plurality of other non-contact ribs are concentrically arranged in an annular shape in the outer peripheral portion of the other main body portion, and the height is lower than the other support pins, and the adjacent other Between the non-contact ribs, the plurality of other pins are provided. A joint system comprising a joint system having a joint device according to claim 1 or 2, characterized in that: The processing station includes the above-described bonding device, and the loading/unloading station can store a plurality of first substrates, a second substrate, or a superposed substrate in which the first substrate and the second substrate are joined, and the first processing unit is carried in and out of the processing station. a substrate, a second substrate, or a superposed substrate, wherein the processing station includes a surface modification device that reforms a surface on which the first substrate or the second substrate is bonded, and a surface hydrophilization device that passes through the surface modification device The surface of the modified first substrate or the second substrate is hydrophilized; and the transfer device transports the first substrate, the second substrate, or the superposed substrate to the surface modification device, the surface hydrophilization device, and the bonding device. In the above bonding apparatus, the first substrate that has been hydrophilized by the surface hydrophilization device is bonded to the second substrate. A bonding method is a method of bonding substrates to each other by using a bonding apparatus, wherein the bonding apparatus includes: a first holding portion that vacuum-absorbs the first substrate and is held by the lower portion; and a second holding portion Provided below the first holding portion, the second substrate is vacuumed and adsorbed and held on the upper surface, and the second holding portion has a main body portion for vacuuming the second substrate, and a plurality of pins are provided. In the body portion and contacting the second substrate a back surface; and a plurality of non-contact ribs, which are concentrically arranged in a ring shape in the outer peripheral portion of the body portion, and have a height lower than the support pin, and are disposed between the adjacent non-contact ribs In the first holding process, the first holding unit vacuums and holds the first substrate, and the second holding unit includes the second holding unit. The second substrate is sequentially vacuumed and held from the center portion toward the outer peripheral portion, and the bonding process, and thereafter, the first substrate held by the first holding portion and the second substrate held by the second holding portion are held 2 The substrates are arranged opposite each other and joined. The joining method according to claim 9, wherein the second holding portion further includes a contact rib, and the main body portion is concentrically provided in a ring shape inside the non-contact rib And the second holding portion is configured to be capable of setting a vacuum of the second substrate in the suction region on the inner side of the contact rib and the suction region on the outer side of the contact rib, in the second holding portion. (2) In the holding process, after the second substrate is adsorbed on the inner suction region, the second substrate is adsorbed on the outer suction region. The joining method of claim 9 or 10, wherein In the second holding process, in the main body portion, the outer peripheral portion of the second substrate is evacuated from a suction port formed in a region where the plurality of non-contact ribs are provided. The joining method of claim 9 or 10, wherein the body portion is concentrically divided into a plurality of pin supporting regions, and in the plurality of pin supporting regions, the plurality of the inner pin supporting regions The interval between the pins is smaller than the interval between the plurality of pins of the outer pin region, and in the bonding process, the center portion of the first substrate and the inner pin region of the second substrate are pressed. After the contact, the vacuuming of the first substrate by the first holding portion is stopped, and the first substrate and the second substrate are sequentially joined from the center portion of the first substrate toward the outer peripheral portion. The joining method of the ninth or tenth aspect of the invention, wherein the first substrate and the first substrate are joined while adjusting the temperature of the second substrate by the temperature adjusting mechanism provided in the second holding portion 2 substrates. The bonding method according to claim 13, wherein the temperature adjustment mechanism includes: a first temperature adjustment unit that adjusts a temperature of a peripheral portion of the second substrate; and a second temperature adjustment unit that is in the second substrate The temperature is adjusted in the central portion on the inner side of the outer peripheral portion. In the jointing process, the set temperature of the first temperature adjustment unit is higher than the set temperature of the second temperature adjustment unit. The joining method of claim 9 or 10, wherein the first holding portion has another body portion that evacuates the first substrate, and the plurality of other pins are provided on the other body portion, and Contacting the back surface of the first substrate; and the plurality of other non-contact ribs are concentrically arranged in an annular shape in the outer peripheral portion of the other main body portion, and the height is lower than the other support pins, and the adjacent other The plurality of other support pins are provided between the non-contact ribs. In the first holding process, the first substrate is sequentially evacuated from the center portion toward the outer peripheral portion by the first holding portion. And keep it. A readable computer memory medium storing a program for operating on a computer controlling a control portion of the bonding device such that the bonding method of claim 9 or 10 is performed by the bonding device .