TW201401383A - Bonding apparatus, bonding system, bonding method and computer strage medium - Google Patents

Abstract

To inhibit bubbles from occurring at an outer peripheral part between substrates and properly bond the substrates to each other. A bonding apparatus includes: an upper chuck 230 for evacuating from the bottom to thereby suck and hold an upper wafer WU; and a lower chuck 231 provided below the upper chuck 230 for evacuating from the top to thereby suck and hold a lower wafer WL. The upper chuck 230 has a first heating mechanism 242 for heating the upper wafer WU to a predetermined temperature. The lower chuck 231 has a second heating mechanism 262 for heating the lower wafer WL to a predetermined temperature.

Description

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

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

In recent years, semiconductor devices have progressed in high integration. When a plurality of high-integration semiconductor devices are arranged in a horizontal plane, and the semiconductor devices are connected to each other for wiring, the wiring length is increased, so that the resistance of the wiring is increased, and the wiring delay is changed. Big doubts.

Therefore, the proposal adopts a three-dimensional integrated body technique in which a semiconductor device is three-dimensionally stacked. In the three-dimensional integrated technology, for example, two semiconductor wafers (hereinafter simply referred to as "wafers") are bonded by a bonding system. For example, the bonding system has a surface hydrophilizing device that hydrophilizes the surface on which the substrate is bonded, and a bonding device that bonds the substrates to which the surface hydrophilizing device is hydrophilized. The related bonding system is that the surface hydrophilizing device supplies pure water to the surface of the substrate to carry out the surface of the substrate. After the hydrophilization, the substrates are bonded to each other by Van der Waals force and hydrogen bonding (intermolecular force) in the bonding apparatus (Patent Document 1).

[Previous Technical Literature] [Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open Publication No. 2011-187716

However, the inventors of the present invention have forgotten the review, and it is understood that when the bonding system described in Patent Document 1 is used, bubbles may occur on the outer peripheral portion between the substrates to be joined. Further, a mechanism for generating bubbles in the outer peripheral portion between the substrates will be described later.

The present invention has been made in view of the related problems, and an object thereof is to suppress occurrence of air bubbles in the outer peripheral portion between the substrates, and to appropriately bond the substrates to each other.

In order to achieve the above object, the present invention provides a bonding apparatus for bonding a substrate to each other by intermolecular force, and is characterized in that: a vacuum is applied to the lower surface to suck the first holding member holding the first substrate, and is provided in a second holding member that holds the second substrate under the first holding member and is vacuumed thereon; at least the first holding member or the front portion The second holding member has a heating mechanism that heats at least the first substrate or the second substrate to a specific temperature.

After intensive review, the inventors have learned that, for example, when the substrates are joined by intermolecular force in the case of using the bonding system of Patent Document 1, the bubbles in the outer peripheral portion between the substrates are caused by the surface hydrophilization of the substrate. It occurs when pure water is supplied. The pure water to be supplied for the surface of the substrate to be hydrophilized includes pure water to be used for bonding the substrates to each other, and pure water remaining in the other portions. Then, for example, the bonding between the substrates is diffused from the central portion to the outer peripheral portion of the substrate, and the diffusion bonding causes the remaining portion of the pure water to float on the surface of the substrate and reach the outer peripheral portion of the substrate by a so-called bonding wave. . Since the remaining portion of the pure water remains, the pure water becomes air, and it is presumed that the bubbles occur at the outer peripheral portion between the substrates.

According to the present invention, at least the first substrate or the second substrate can be heated to a specific temperature when the first substrate held by the first holding member and the second substrate held by the second holding member are joined to each other. . The pure water supplied to the remaining portions of the surfaces of the first substrate and the second substrate can be removed from the surfaces of the first substrate and the second substrate by the related heating. Therefore, it is possible to suppress the occurrence of bubbles in the outer peripheral portion between the substrates, and to appropriately bond the substrates to each other by the intermolecular force.

According to another aspect of the invention, there is provided a bonding system of the bonding apparatus, comprising: a processing station including the bonding device; and the first substrate, the second substrate, or the first substrate and the second substrate can be The joined coincident substrates are respectively retained in plurality and will be treated for the aforementioned processing stations. a substrate, a second substrate, or a superposed substrate; a loading and unloading station that carries in and out; and the processing station includes a surface modifying device that reforms a surface of the first substrate or the second substrate to be joined, and the surface is modified a surface hydrophilization device that hydrophilizes the surface of the first substrate or the second substrate on which the reforming device is modified, and the first substrate is transported to the surface modification device, the surface hydrophilization device, and the bonding device. In the transfer device for the second substrate or the superposed substrate, the first substrate and the second substrate which are hydrophilized by the surface hydrophilization device are bonded to each other.

Further, the present invention, which is formed by another aspect, is a method of joining bonded substrates by intermolecular force, and is characterized in that the first substrate to be held by the lower surface of the first holding member is provided and provided When the second substrate held by the upper surface of the second holding member is joined to the lower side of the first holding member, at least the first substrate or the second substrate is heated to a specific temperature.

Further, according to the present invention, which is formed by another aspect, it is desired to use the bonding apparatus to perform the above-described bonding method, and to provide a computer memory medium that can be read by a program stored on a computer that controls the control unit of the bonding apparatus.

According to the invention, it is possible to suppress the occurrence of bubbles in the outer peripheral portion between the substrates, and to appropriately bond the substrates to each other by the intermolecular force.

1‧‧‧ joint system

2‧‧‧ Moving out of the station

3‧‧‧ Processing station

30‧‧‧Surface modification device

40‧‧‧ Surface Hydrophilization Unit

41‧‧‧Joining device

60‧‧‧ Wafer transfer field

230‧‧‧Upper chuck

231‧‧‧ lower chuck

242‧‧‧1st heating mechanism

262‧‧‧2nd heating mechanism

300‧‧‧Control Department

W _U ‧‧‧ Wafer

W _L ‧‧‧ under wafer

W _T ‧‧‧Cover wafer

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

Fig. 2 is a schematic side view showing the internal structure of the joint system of the present embodiment.

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

Fig. 4 is a schematic longitudinal cross-sectional view showing the configuration of a surface modifying device.

Figure 5 is a plan view of the ion-passing structure.

Fig. 6 is a schematic longitudinal cross-sectional view showing the configuration of a surface hydrophilizing device.

Fig. 7 is a schematic cross-sectional view showing the configuration of a surface hydrophilizing device.

Fig. 8 is a schematic cross-sectional view showing the configuration of the joining device.

Fig. 9 is a schematic longitudinal cross-sectional view showing the configuration of a joining device.

Fig. 10 is a schematic side view showing the configuration of a position adjusting mechanism.

Fig. 11 is a schematic plan view showing the configuration of the reversing mechanism.

Fig. 12 is a schematic side view showing the configuration of the reversing mechanism.

Fig. 13 is a schematic side view showing the configuration of the reversing mechanism.

Fig. 14 is a schematic side view showing the configuration of a holding arm and a holding member.

Fig. 15 is a schematic longitudinal cross-sectional view showing the configuration of an upper chuck and a lower chuck.

Figure 16 is a plan view of the upper chuck as seen from below.

Figure 17 is a plan view of the lower chuck as seen from above.

Figure 18 is a flow chart showing the main steps of the wafer bonding process.

Fig. 19 is an explanatory view showing a state in which the horizontal position of the upper wafer and the lower wafer is adjusted.

Figure 20 shows the adjustment of the vertical position of the upper and lower wafers. An illustration of the situation.

21 is an explanatory view showing a state in which the center portion of the upper wafer is brought into contact with the center portion of the lower wafer by pressing.

Fig. 22 is an explanatory view showing a state in which the upper wafer is sequentially abutted to the lower wafer.

Fig. 23 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. 24 is an explanatory view showing a state in which the upper wafer and the lower wafer are joined.

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

In the bonding system 1, as shown in FIG. 3, for example, wafers W _U and W _{L which are} two substrates are joined. Hereinafter, the wafer disposed on the upper side is referred to as "upper wafer W _U " of the first substrate, and the wafer disposed on the lower side is referred to as "lower wafer W _L " of the second substrate. Further, the joint surface on which the 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 "inside W _U2 ". Similarly, the joint surface on which the lower wafer W _L is bonded is referred to as "surface W _L1 ", and the surface on the opposite side to the surface W _L1 is referred to as "inner W _L2 ". Next, the bonding system 1 bonds the upper wafer W _U and the lower wafer W _{L to} form a superposed wafer W _{T of the} superposed substrates.

The bonding system 1 has a card 匣C _U , C _L , C _{T that} can carry a plurality of wafers W _U , W _L and a plurality of coincident wafers W _T , for example, as shown in FIG. 1 . The loading/unloading station 2 is configured to be integrally connected to the processing station 3 including various processing devices that perform specific processing on the wafers W _U and W _L and the superimposed wafers W _T .

A cassette mounting table 10 is provided at the loading/unloading station 2. In the cassette mounting table 10, a plurality of, for example, four cassette mounting plates 11 are provided. The cassette mounting plates 11 are arranged side by side in a row in the X direction (up and down direction in FIG. 1) in the horizontal direction. The cassette mounting plate 11, the cassette loading system can be moved out of engagement C _U outside of the system 1, C _L, when C _T, mounted cassette _{C U, C L, C T} . In this manner, the loading/unloading station 2 is configured to hold a plurality of wafers W _U , a plurality of wafers W _L , and a plurality of superposed wafers W _T . Moreover, the number of the cassette mounting plates 11 is not limited to this embodiment, and can be arbitrarily set. In addition, one of the cassettes can also be used for the recovery of abnormal wafers. That is, it is possible to separate the wafer from which the normal wafer W _{T is} abnormally caused by the bonding of the upper wafer W _U and the lower wafer W _L due to various factors. In the present embodiment, among the plurality of cassettes C _T , one cassette C _{T is} used for the abnormal wafer recovery, and the other cassette C _{T is} used as the normal overlap wafer W _{T for} storage.

In the carry-in/out station 2, the 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 in the X direction and is freely movable over the transfer path 21. The wafer transfer device 22 can move freely in the vertical direction and around the vertical axis (theta direction), and can carry the cassettes C _U , C _L , and C _T on the respective cassette mounting plates 11 and the processing station 3 to be described later. The wafers W _U and W _L and the superposed wafer W _T are transferred between the transistor devices 50 and 51 of the third processing region G3.

In the processing station 3, for example, a plurality of processing units G1, G2, and G3 are provided. For example, the first processing area G1 is provided on the front side of the processing station 3 (the negative side in the X direction of FIG. 1), and the second processing area is provided on the back side of the processing station 3 (the positive side in the X direction of FIG. 1). G2. Moreover, the third processing zone 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 treatment zone G1, disposed wafer W _U, W _L surface W _U1, W _L1 by reforming the surface modification apparatus 30. In the present embodiment, the surface modification device 30 is formed by combining SiO ₂ which cuts the surfaces W _U1 and W _L1 of the wafers W _U and W _L to form a single bonded SiO, and then is easily hydrophilized. The method is to modify the surface W _U1 , W _L1 .

For example, in the second treatment zone G2, for example, by diluting the wafer W _U, W _L surface W _U1, W _L1 and the hydrophilized surface W _U1, W _L1 hydrophilic surface of the cleaning apparatus 40, The bonding apparatus 41 that bonds the wafers W _U and W _L is arranged side by side in the Y direction in the horizontal direction from the side of the loading/unloading station 2 in this order.

For example, in the third processing block G3, the wafers W _U and W _L and the transistor devices 50 and 51 of the superposed wafer W _T are disposed in two stages in order as shown in FIG. 2 .

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

The wafer transfer device 61 has, for example, a transfer arm that can move freely in the vertical direction, the horizontal direction (Y direction, X direction), and the vicinity of the vertical axis. The wafer transfer device 61 is movable in the wafer transfer area 60, and transports the wafers W _U , W _L in the surrounding specific processing area G1, the second processing area G2, and the specific processing in the third processing area G3. , coincident wafer W _T .

Next, the configuration of the surface modification device 30 described above will be described. The surface modifying device 30 has a processing container 100 as shown in FIG. The upper surface of the container 100 is opened, and a radial line slot antenna 120, which will be described later, is disposed in the upper opening, and the processing container 100 is configured to be able to seal the inside.

A loading/unloading port 101 of the wafers W _U and W _L is formed on the side surface of the processing container 100 on the side of the wafer transfer region 60, and a gate valve 102 is provided in the loading/unloading port 101.

On the bottom surface of the processing container 100, an intake port 103 is formed. At the intake port 103, the intake pipe 105 that is connected to the air suction device 104 that decompresses the atmosphere inside the processing container 100 to a specific degree of vacuum is connected.

Further, on the bottom surface of the processing container 100, a mounting table 110 on which the wafers W _U and W _{L are} placed is provided. The mounting table 110 can mount the wafers W _U and W _L by, for example, electrostatic attraction or vacuum suction. On the mounting table 110, an ion current meter 111 is provided to measure an ion current generated by ions (oxygen ions) of the processing gas irradiated onto the wafers W _U and W _L on the mounting table 110 as will be described later.

The stage 110 has, for example, a temperature adjustment mechanism 112 that allows a cooling medium to flow. The temperature adjustment mechanism 112 is connected to the adjustment The liquid temperature adjusting unit 113 that cools the temperature of the medium. Next, the liquid temperature adjusting unit 113 can adjust the temperature of the refrigerant medium and control the temperature of the mounting table 110. As a result, the wafer W placed on the mounting table 110 can be maintained at a specific temperature.

Further, below the mounting table 110, a lifting plug (not shown) for supporting the lifting and lowering wafers W _U and W _L from below is provided. The lift pin is inserted through a through hole (not shown) formed in the mounting table 110 so as to be protruded from the upper surface of the mounting table 110.

A radiation slot antenna 120 (RLSA: Radial Line Slot Antenna) for supplying plasma for plasma generation is provided in the upper opening of the processing container 100. The radiation slot antenna 120 is an antenna body 121 having an opening below. Inside the antenna main body 121, for example, a flow path (not shown) through which a cooling medium flows is provided.

A plurality of grooves are formed in the opening portion below the antenna main body 121, and a groove plate 122 which functions as an antenna function is provided. The material of the groove plate 122 is made of a conductive material such as copper, aluminum, nickel or the like. A retardation plate 123 is provided on the upper portion of the slot plate 122 in the antenna body 121. The material of the retardation plate 123 is a low loss dielectric material such as quartz, alumina, aluminum nitride or the like.

Below the antenna body 121 and the slot plate 122, a microwave transmitting plate 124 is provided. The microwave transmitting plate 124 is disposed, for example, so as to block the inside of the processing container 100 via a sealing material (not shown) such as an O-ring. The material of the microwave transmitting plate 124 is a dielectric such as quartz or Al ₂ O ₃ .

In the upper portion of the antenna body 121, a coaxial waveguide 126 that passes to the microwave oscillation device 125 is connected. The microwave oscillation device 125 is disposed outside the processing container 100, and is capable of emitting microwaves of a specific frequency, for example, 2.45 GHz, to the radiation slot antenna 120.

With the related configuration, the microwave emitted from the microwave oscillation device 125 is propagated into the radiation slot antenna 120, compressed by the slow phase plate 123, and shortened in wavelength, and the circular wave is generated by the slot plate 122. It is radiated into the processing container 100 through the microwave transmitting plate 124.

On the side surface of the processing container 100, a gas supply pipe 130 for supplying oxygen as a processing gas to the inside of the processing container 100 is connected. The gas supply pipe 130 is disposed above the ion-passing structure 140 to be described later, and supplies oxygen to the plasma generation region R1 in the processing container 100. Further, the gas supply pipe 130 is connected to a gas supply source 131 that internally stores oxygen. The gas supply pipe 130 is provided with a supply machine group 132 including a valve for controlling the flow of oxygen, a flow rate adjusting unit, and the like.

An ion-passing structure 140 is provided between the mounting table 110 in the processing container 100 and the radiation slot antenna 120. That is, the ion-passing structure 140 is designed to classify the inside of the processing container 100 such that oxygen supplied from the gas supply pipe 130 is plasma-treated by microwaves radiated from the radiation slot antenna 120. The plasma generation region R1 is a processing region R2 in which the surfaces W _U1 and W _L1 of the wafers W _U and W _L on the mounting table 110 are modified by oxygen ions generated in the plasma generation region R1.

The ion-passing structure 140 has a pair of electrodes 141, 142. Hereinafter, an electrode disposed on the upper portion is referred to as "upper electrode 141", and an electrode disposed on the lower portion is referred to as "lower electrode 142". An insulating material 143 that electrically insulates the pair of electrodes 141 and 142 is provided between the pair of electrodes 141 and 142.

Each of the electrodes 141 and 142 has a circular shape which is larger in plan than the diameters of the wafers W _U and W _L as shown in FIGS. 4 and 5 . Further, in each of the electrodes 141 and 142, a plurality of openings 144 through which oxygen ions pass are formed from the plasma generation region R1 to the treatment region R2. The plurality of openings 144 are arranged, for example, in a lattice shape. Further, the shape or arrangement of the plurality of openings 144 is not limited to the present embodiment, and can be arbitrarily set.

Here, the size of each opening portion 144 is preferably set to be shorter than, for example, the wavelength of the microwave radiated from the radiation slot antenna 120. By doing so, the microwave supplied from the radiation slot antenna 120 can be reflected by the ion-passing structure 140, and the microwave can be prevented from entering the processing area R2. As a result, the wafers W _U and W _L on the mounting table 110 are not directly exposed to microwaves, and damage to the wafers W _U and W _L due to microwaves can be prevented.

In the ion-passing structure 140, a power source 145 that applies a specific voltage between the pair of electrodes 141 and 142 is connected. The specific voltage applied by the power source 145 can be controlled by the control unit 300, which will be described later, and the maximum voltage is, for example, 1 KeV. Further, in the ion-passing structure 140, an ammeter 146 for measuring the current flowing through the pair of electrodes 141 and 142 is successively performed.

Next, the configuration of the surface hydrophilization device 40 described above will be described. The surface hydrophilization device 40 has a processing container 150 that can seal the inside as shown in FIG. On the side surface of the processing container 150 on the side of the wafer transfer area 60, as shown in FIG. 7, the loading/unloading inlet 151 of the wafers W _U and W _L is formed, and the opening and closing inlet 151 is provided with a switching shutter 152.

In the center portion of the processing container 150, as shown in Fig. 6, a rotating chuck 160 that holds the wafers W _U and W _L to rotate is provided. The rotating chuck 160 has a horizontal upper surface on which a suction port (not shown) for sucking the wafers W _U , W _L is provided, for example. The wafers W _U , W _L can be held by the suction chuck 160 by suction from the suction port.

The spin chuck 160 has, for example, a chuck drive unit 161 including a motor or the like, and the chuck drive unit 161 can rotate at a specific speed. Further, the chuck driving unit 161 is provided with a lifting drive source such as a cylinder, and the rotating chuck 160 is allowed to freely move up and down.

Around the spin chuck 160, a cup 162 that receives and collects liquid that has been scattered or dropped from the wafers W _U and W _{L is provided} . Below the cup 162, an exhaust pipe 164 that discharges the recovered liquid and an exhaust pipe 164 that exhausts the atmosphere in the vacuum suction cup 162 is connected.

As shown in Fig. 7, in the negative direction of the X direction of the cup 162 (the direction below the direction of Fig. 7), a rail 170 extending in the Y direction (the left and right direction of Fig. 7) is formed. The rail 170 is formed, for example, from the outside in the negative direction of the Y direction of the cup 162 (the left direction in FIG. 7) to the outside in the positive direction of the Y direction (the right direction in FIG. 7). On the rail 170, for example, a nozzle arm 171 and a scrub arm 172 are mounted.

The nozzle arm 171 supports a pure water nozzle 173 that supplies pure water to the wafers W _U and W _L as shown in FIGS. 6 and 7 . The nozzle arm 171 is freely movable over the rail 170 by the nozzle driving portion 174 shown in FIG. Thereby, the pure water nozzle 173 can be moved from the outer waiting portion 175 provided on the positive side in the Y direction of the cup 162 to the upper portion of the wafers W _U and W _L in the cup 162, and further The wafers W _U and W _L are moved in the radial direction over the wafers W _U and W _L . Further, the nozzle arm 171 can be freely moved up and down by the nozzle driving unit 174, and the height of the pure water nozzle 173 can be adjusted.

In the pure water nozzle 173, as shown in Fig. 6, a supply pipe 176 for supplying pure water to the pure water nozzle 173 is connected. The supply pipe 176 is connected to a pure water supply source 177 that internally stores pure water. Further, the supply pipe 176 is provided with a supply device group 178 including a valve for controlling the flow of pure water, a flow rate adjusting portion, and the like.

The scrubbing arm 172 supports the scrubbing fixture 180. At the tip end portion of the scrubbing fixture 180, for example, a plurality of filament-like or sponge-like brushes 180a are provided. The scrubbing arm 172 can be freely moved over the rail 170 by the washer driving unit 181 shown in FIG. 7, and the scrubbing fixture 180 can be moved from the outside in the negative direction of the Y direction of the cup 162 to the cup 162. Above the center of the wafers W _U and W _L . Further, the scrubbing arm 172 can be freely moved up and down by the washer driving unit 181, and the height of the scrubbing fixture 180 can be adjusted.

Further, in the above configuration, the pure water nozzle 173 and the scrubbing washer 180 are respectively supported by different arms, but may be supported by The same arm. Further, the pure water nozzle 173 may be omitted, and the pure water may be supplied from the scrubbing fixture 180. Further, the cup 162 may be omitted, and a discharge pipe that discharges the liquid on the bottom surface of the processing container 150 and an exhaust pipe that exhausts the atmosphere in the processing container 150 may be connected. Further, in the surface hydrophilization device 40 having the above configuration, a static electricity remover (not shown) for preventing electrification may be provided.

Next, the configuration of the above-described joining device 41 will be described. The joining device 41 has a processing container 190 that can seal the inside as shown in FIG. On the side surface of the processing container 190 on the side of the wafer transfer region 60, the wafers W _U and W _L and the loading/unloading port 191 of the superposed wafer W _T are formed, and the opening and closing port 191 is provided with a switching shutter 192.

The inside of the processing container 190 is partitioned into the transport area T1 and the processing area T2 by the inner wall 193. The above-described carry-in/out port 191 is formed on the side surface of the processing container 190 in the transport area T1. Further, on the inner wall 193, the wafers W _U and W _L and the carry-in/out ports 194 of the superposed wafers W _T are formed.

On the positive side in the X direction of the transport area T1, a transistor 200 for temporarily placing the wafers W _U and W _L and superposing the wafer W _{T is provided} . The transistor 200 is formed, for example, in two stages, and any two of the wafers W _U and W _L and the superposed wafers W _T can be simultaneously placed.

In the transport area T1, a wafer transfer mechanism 201 is provided. As shown in FIGS. 8 and 9, the wafer transfer mechanism 201 has, for example, a transfer arm that is movable in the vertical direction, the horizontal direction (Y direction, the X direction), and the vicinity of the vertical axis. Next, the wafer transfer mechanism 201 can transfer 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 210 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 transport area T1. The position adjusting mechanism 210 has a base 211, a holding portion 212 for holding the holding wafers W _U and W _L for rotation, and a position for detecting the notches of the wafers W _U and W _L as shown in FIG. 10 . The detecting unit 213. Next, the position adjusting mechanism 210, by the Department of the wafer W _U while being sucked holding the holding portion 212, W _L while being rotated to the position detecting portion 213 detects the wafer W _U, W _L is the score portion, adjusting The orientation of the notch portion adjusts the orientation of the wafers W _U and W _{L in the} horizontal direction.

Further, in the transport area T1, an inversion mechanism 220 for inverting the front surface of the upper wafer W _U is provided. The reversing mechanism 220 has a holding arm 221 that holds the upper wafer W _U as shown in FIGS. 11 to 13 . The holding arm 221 extends in the horizontal direction (the Y direction in FIGS. 11 and 12). Further, a holding member 222 that holds the upper wafer W _U is provided at the holding arm 221, for example, four places. The holding member 222 is configured to be movable in the horizontal direction against the holding arm 221 as shown in FIG. Further, a notch 223 for holding the outer peripheral portion of the upper wafer W _{U is} formed on the side surface of the holding member 222. Then, the holding members 222 are capable of breaking in and holding the upper wafer W _U .

The holding arm 221 is supported by a first driving unit 224 including a motor or the like as shown in FIGS. 11 to 13 . The first driving unit 224 allows the holding arm 221 to freely rotate around the horizontal axis. Further, the holding arm 221 is freely rotatable about the first driving portion 224, and is freely movable in the horizontal direction (Y direction in FIGS. 11 and 12). Below the first drive unit 224, for example, a second drive unit 225 including a motor or the like is provided. The second driving unit 225 allows the first driving unit 224 to move in the vertical direction along the support post 226 extending in the vertical direction. In this manner, the first driving unit 224 and the second driving unit 225 are used to move the upper wafer W _U held by the holding member 222 around the horizontal axis and to move in the vertical direction and the horizontal direction. Further, the upper wafer W _U held by the holding member 222 is rotatable about the first driving portion 224 and moved between the position adjusting mechanism 210 and the upper chuck 230 to be described later.

In the field of treatment T2, as shown in FIGS. 8 and 9 will be provided on the wafer W _U held in it as sucking on the first holding member below the chuck 230, and the lower wafer W _L placed on the upper surface and The holding chuck 231 is held as the second holding member. The lower chuck 231 is disposed below the upper chuck 230 and is configured to be disposed to face the upper chuck 230. That is, the upper wafer W _U held by the upper chuck 230 and the lower wafer W _L held by the lower chuck 231 can be disposed to face each other.

The upper chuck 230 is supported by a support member 232 provided on the ceiling surface of the processing container 190 as shown in FIG. The support member 232 supports the upper outer peripheral portion of the upper chuck 230. Below the lower chuck 231, a chuck driving portion 234 is provided via a shaft 233. By the chuck driving portion 234, the lower chuck 231 can be freely moved up and down in the vertical direction and can be freely moved in the horizontal direction. Further, the chuck chuck 234 is used to freely rotate the lower chuck 231 around the vertical axis. Further, below the lower chuck 231, a lift pin (not shown) for supporting the lower wafer W _L for lowering and lowering is provided. The lift pin is inserted through a through hole (not shown) formed in the lower chuck 231 so as to be protruded from the upper surface of the lower chuck 231.

The upper chuck 230 is divided into a plurality of fields 230a, 230b, 230c as shown in FIG. The fields 230a, 230b, and 230c are disposed in this order from the center portion to the outer periphery of the upper chuck 230 as shown in FIG. Next, the field 230a appears to have a circular shape in the plane, while the fields 230b, 230c appear to have an annular shape in plan. In each of the fields 230a, 230b, and 230c, as shown in Fig. 15, the suction pipes 240a, 240b, and 240c for holding and holding the upper wafer W _U are separately provided. Different vacuum pumps 241a, 241b, and 241c are connected to the respective suction pipes 240a, 240b, and 240c. Therefore, the upper chuck 230 is configured to be capable of setting the vacuum of the upper wafer W _U in each of the fields 230a, 230b, and 230c.

In addition, hereinafter, the above three fields 230a, 230b, and 230c are referred to as a first field 230a, a second field 230b, and a third field 230c, respectively. Further, the suction pipes 240a, 240b, and 240c are referred to as a first suction pipe 240a, a second suction pipe 240b, and a third suction pipe 240c, respectively. In addition, the vacuum pumps 241a, 241b, and 241c are referred to as a first vacuum pump 241a, a second vacuum pump 241b, and a third vacuum pump 241c, respectively.

Inside the upper chuck 230, a first heating mechanism 242 that heats the upper wafer W _U is provided. Further, for example, a heater is used in the first heating mechanism 242.

A through hole 243 that penetrates the upper chuck 230 in the thickness direction is formed in a central portion of the upper chuck 230. The central portion of the upper chuck 230 corresponds to a central portion of the wafer W _U held by the upper chuck 230. Next, the through hole 243 is inserted into the push pin 251 of the pressing member 250 which will be described later.

On the upper surface of the upper chuck 230, a pressing member 250 that presses the center portion of the upper wafer W _U is provided. The pressing member 250 has a cylinder structure, and has a pressing bolt 251 and an outer cylinder 252 that serves as a guide when the pressing bolt 251 is moved up and down. The push pin 251 is inserted into the through hole 243 by a driving portion (not shown) such as a built-in motor, and is movable up and down in the vertical direction. Next, when the wafer W _U and W _{L are} joined, the pressing member 250 can press the center portion of the upper wafer W _{U and} the center portion of the lower wafer W _L to be pressed.

The upper chuck 230 is provided with a photographing member 253 on the upper surface W _L1 of the lower wafer W _L . For example, a wide-angle type CCD camera is employed in the upper photographing member 253. Further, the upper photographing member 253 may be provided on the upper chuck 230.

The lower chuck 231 is divided into a plurality of fields 231a, 231b as shown in FIG. These fields 231a, 231b are arranged in this order from the center portion to the outer periphery of the lower chuck 231. Next, the field 231a plane appears to have a circular shape, while the field 231b plane appears to have a ring shape. In each of the fields 231a and 231b, as shown in Fig. 15, suction pipes 260a and 260b for holding and holding the lower wafer W _L are separately provided. Different vacuum pumps 261a and 261b are connected to the respective suction pipes 260a and 260b. Therefore, the lower chuck 231 is configured to be capable of setting the vacuum of the lower wafer W _L in each of the fields 231a and 231b.

Inside the lower chuck 231, a second heating mechanism 262 that heats the lower wafer W _L is provided. Further, for example, a heater is used in the second heating mechanism 262.

On the outer peripheral portion of the lower chuck 231, a stopper member 263 for preventing the wafers W _U , W _L and the superposed wafer W _T from flying or falling off the lower chuck 231 is provided. The stopper member 263 extends in the vertical direction so that the top portion is located at least above the superposed wafer W _T on the lower chuck 231. Further, the stopper member 263 is provided at a plurality of places, for example, five places on the outer peripheral portion of the lower chuck 231 as shown in FIG.

In the lower chuck 231, as shown in Fig. 15, a photographing member 264 under the surface W _U1 on which the upper wafer W _U is photographed is provided. For example, a wide-angle type CCD camera is employed in the lower photographing member 264. Further, the lower photographing member 264 may be provided on the lower chuck 231.

In the above joint system 1, as shown in Fig. 1, a control unit 300 is provided. The control unit 300 is, for example, a computer and has a program storage unit (not shown). In the program housing portion, a program for controlling the processing of the wafers W _U , W _{L of the} bonding system 1 and the wafer W _T is accommodated. In addition, the program storage unit also accommodates a drive system for controlling the above-described various processing devices, transport devices, and the like, and realizes a program for bonding the wafer bonding process described later in the system 1. Further, the program is recorded on a computer-readable hard disk (HD), floppy disk (FD), compact disc (CD), optical disk (MO), memory card, etc. Alternatively, the memory unit H may be installed by the control unit 300.

Next, a bonding processing method of the wafers W _U and W _L by the bonding system 1 configured as described above will be described. Fig. 18 is a flow chart showing an example of main steps of the related wafer bonding process.

First, the wafer accommodating the plural pieces of cassettes W _U C _U, accommodating the plural pieces of the cassettes wafer W _L C _L, and an empty cassette C _T, is placed on the loading unloading station 2 of the specific The cassette is placed on the board 11. Thereafter, the upper wafer W _{U in} the cassette C _U is taken out by the wafer transfer device 22 and transported to the crystal 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. The wafer W _{U carried in the} surface modification device 30 is transferred from the wafer transfer device 61 to the upper surface of the mounting table 110. Thereafter, the wafer transfer device 61 is withdrawn from the surface modification device 30, and the gate valve 102 is closed. Further, the wafer W _U placed on the mounting table 110 is maintained at a specific temperature, for example, 25 ° C to 30 ° C by the temperature adjusting mechanism 112.

Thereafter, the air suction device 104 is operated, and the atmosphere inside the processing container 100 is depressurized to a specific degree of vacuum through the air inlet 103, for example, 67 Pa to 333 Pa (0.5 Torr to 2.5 Torr). Next, in the manner described later, the atmosphere in the processing container 100 during the processing of the wafer W _U is maintained at the above specific degree of vacuum.

Thereafter, oxygen is supplied from the gas supply pipe 130 to the plasma generation region R1 in the processing container 100. Further, microwaves of, for example, 2.45 GHz are radiated from the radiation slot antenna 120 to the plasma generation region R1. With the radiation of the microwave, oxygen is excited and plasma is generated in the field of plasma generation R1. Ionization, such as oxygenation. At this time, the microwave traveling downward is reflected by the ion-passing structure 140 and stored in the plasma generation region R1. As a result, a high-density plasma is generated in the plasma generation field R1.

Then, in the ion-passing structure 140, a specific voltage is applied to the pair of electrodes 141, 142 by the power source 145. In this way, only the oxygen ions generated in the plasma generation region R1 are allowed to flow into the processing region R2 through the opening portion 144 of the ion-passing structure 140 by the pair of electrodes 141 and 142.

At this time, the control unit 300 controls the voltage applied between the pair of electrodes 141 and 142 by controlling the voltage applied between the pair of electrodes 141 and 142. The energy imparted to the oxygen is sufficient to cut off the double bond of SiO ₂ of the surface W _U1 of the upper wafer W _U to form the energy of the single bonded SiO, and is set to not damage the energy of the surface W _U1 .

Further, at this time, the current value of the current flowing between the pair of electrodes 141 and 142 is measured by the ammeter 146. Based on the measured current value, the oxygen ion passage amount passing through the ion passage structure 140 is grasped. Then, the control unit 300 controls the oxygen supply amount from the gas supply pipe 130 or the voltage between the pair of electrodes 141 and 142 so that the throughput is a specific value based on the oxygen ion throughput. Etc., various parameters (parameter).

Thereafter, the oxygen ions introduced into the processing region R2 are irradiated and injected onto the surface W _U1 of the wafer W _U on the mounting table 110. Next, the oxygen ions are irradiated, so that the surface of SiO ₂ W _U1 of the double binding is cut and bound into a single SiO. Further, because the use of the modified oxygen ions in the surface W _U1, and let the oxygen ions are irradiated on the surface of the wafer W _U W _U1 itself contribute to the binding of SiO. As a result, the surface W _{U1 of the} upper wafer W _U is modified (step S1 of FIG. 18).

At this time, the current value of the ion current generated by the oxygen ions irradiated onto the surface W _U1 of the upper wafer W _U is measured by the ion current meter 111. Based on the measured current value, the amount of irradiation of oxygen ions irradiated onto the surface W _U1 of the upper wafer W _U is grasped. Then, the control unit 300 controls the amount of oxygen supplied from the gas supply pipe 130 or the voltage between the pair of electrodes 141 and 142 so that the irradiation amount becomes a specific value based on the amount of oxygen ion irradiation to be grasped. Etc., various parameters (parameter).

Next, the upper wafer W _U is transported to the surface hydrophilization device 40 of the second processing region G2 by the wafer transfer device 61. The wafer W _{U carried} on the surface hydrophilization device 40 is transferred and held by the wafer transfer device 61 and held by the rotary chuck 160.

Then, by the nozzle arm 171 so that the pure water nozzle portion 173 waits until the mobile 175 over the central portion of the wafer W _U, and by scrubbing the scrub washing arm 172 so that the upper tool 180 is moved to the wafer W _U. Thereafter, the upper wafer W _{U is} rotated by the spin chuck 160, and pure water is supplied from the pure water nozzle 173 to the upper wafer W _U . As a result, the surface W _U1 of the upper wafer W _U whose surface _modification device 30 is modified adheres to a hydroxyl group (silanol group) to make the surface W _U1 hydrophilized. Further, the surface W _{U1 of the} upper wafer W _U is cleaned by the pure water from the pure water nozzle 173 and the scrubbing fixture 180 (step S2 of Fig. 18). Further, since it is supplied to the pure water of the surface W _U1 of the upper wafer W _U , a part of the pure water hydrophilizes the surface W _U1 in the above-described manner, that is, a bonding crystal is used in the following manner. The circles W _U and W _L , so that the remaining portion of the pure water remains on the surface W _{U1 of the} upper wafer W _U .

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 wafer W _{U carried in the} bonding apparatus 41 is transported to the position adjusting mechanism 210 via the wafer transfer mechanism 201 via the transistor 200. Next, the orientation of the upper wafer W _{U in the} horizontal direction is adjusted by the position adjustment mechanism 210 (step S3 of FIG. 18).

Thereafter, the upper wafer W _{U is} transferred from the position adjustment mechanism 210 to the holding arm 221 of the reversing mechanism 220. Then, in the transport area T1, the inside of the upper wafer W _U is reversed by inverting the holding arm 221 (step S4 of FIG. 18). That is, the surface W _{U1 of} the upper wafer W _U is directed downward.

Thereafter, the holding arm 221 of the reversing mechanism 220 is rotated about the first driving portion 224 and moves below the upper chuck 230. Next, the upper wafer W _{U is} transferred from the inversion mechanism 220 to the upper chuck 230. The upper wafer W _U is attached to the upper chuck 230 so that the inner W _U2 is sucked and held (step S5 of Fig. 18). At this time, all of the vacuum pumps 241a, 241b, 241c operation, the chuck 230 in all areas 230a, 230b, 230c on the wafer W _U evacuated. The wafer W _U, the chuck 230 to be described later to wait until after the wafer W _L is transported to the bonding apparatus 41.

Between the wafer W _U of the above-described process of steps S1 ~ S5, and thereafter the wafer on the wafer W _U W _L followed by processing it. First, the lower wafer W _{L in the} cassette C _L is taken out by the wafer transfer device 22 and transported to the crystal 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 (step S6 of FIG. 18). Further, the modification of the surface W _L1 of the wafer W _L in the step S6 is the same as the above-described step S1.

Thereafter, the wafer W _L line 61 by the wafer transport device is transferred to the hydrophilic surface of the apparatus 40, so that the lower surface of the wafer W _L W _L1 is hydrophilic and the surface W _L1 washing step (S7 in FIG. 18 ). Further, since the surface W _L1 of the wafer W _L is hydrophilized and washed in the step S7, since it is the same as the above-described step S2, a detailed description thereof will be omitted. Further, since it is supplied to the pure water of the surface W _L1 of the lower wafer W _L , a part of the pure water system hydrophilizes the surface W _L1 , which is used to bond the wafer W _{U in the} following manner. , W _L , so the remaining part of the pure water remains on the surface W _{L1 of the} lower wafer W _L .

Thereafter, the wafer W _L line 61 by the wafer transfer apparatus 41 is transferred to the engagement means. The wafer W _{L carried} under the bonding apparatus 41 is transported to the position adjusting mechanism 210 via the wafer transfer mechanism 201 via the transistor 200. Next, the orientation of the lower wafer W _{L in the} horizontal direction is adjusted by the position adjustment mechanism 210 (step S8 of FIG. 18).

Thereafter, the lower wafer W _L is transported to the lower chuck 231 by the wafer transfer mechanism 201, and is sucked and held by the lower chuck 231 (step S9 of FIG. 18). At this time, all of the vacuum pumps 261a and 261b are operated, and the lower wafer W _L is evacuated in all of the fields 231a and 231b of the lower chuck 231. Subsequently, to allow the lower surface of the wafer W _L W _L1 of faces upward, so that the bottom wafer W _L W _L2 inside the lower chuck 231 is held sucked.

Next, positional adjustment in the horizontal direction of both the upper wafer W _U held by the upper chuck 230 and the lower wafer W _L held by the lower chuck 231 is performed. As shown in FIG. 19, a predetermined complex number of, for example, four or more reference points A is formed on the surface W _{L1 of the} lower wafer W _L , and similarly, a predetermined complex number of, for example, four or more points is formed on the surface W _{U1 of the} upper wafer W _U . Reference point B. These reference points A and B are used, for example, in specific patterns formed on the wafers W _L and W _U . Next, the upper photographing member 253 is moved in the horizontal direction, and the surface W _{L1 of the} lower wafer W _L is photographed. Next, the lower photographing member 264 is moved in the horizontal direction, and the surface W _{U1 of the} upper wafer W _U is photographed. Thereafter, the position of the wafer W _L reference point A displayed by the image captured by the upper imaging member 253 and the position of the upper wafer W _U reference point B displayed by the image captured by the lower imaging member 264 are matched. The position of the lower wafer W _{L in the} horizontal direction (including the orientation in the horizontal direction) is adjusted by the lower chuck 231. In other words, the chuck driving unit 234 moves the lower chuck 231 in the horizontal direction to adjust the position of the lower wafer W _{L in the} horizontal direction. Thus, the position in the horizontal direction of the upper wafer W _U and the lower wafer W _L is adjusted (step S10 of FIG. 18). Further, instead of the movement of the upper photographing member 256 and the lower photographing member 264, the upper chuck 230 and the lower chuck 231 may be moved.

Further, the horizontal directions of the wafers W _U and W _L are adjusted by the position adjusting mechanism 210 in steps S3 and S8, and fine adjustment is performed in step S10. Further, in the step S10 of the present embodiment, the specific patterns formed on the wafers W _L and W _U are used as the reference points A and B, but other reference points may be employed. It is possible to use the outer peripheral portion and the notch portion of the wafers W _L and W _U as reference points.

Thereafter, the chuck driving unit 234 raises the lower chuck 231 as shown in FIG. 20 to arrange the lower wafer W _L at a specific position. At this time, the interval between the surface W _{L1 of the} lower wafer W _L and the surface W _{U1 of the} upper wafer W _U is a specific distance, and for example, the lower wafer W _L is disposed so as to be 80 μm to 200 μm. Thus, the position in the vertical direction of the upper wafer W _U and the lower wafer W _L is adjusted (step S11 of FIG. 18). Further, in steps S5 to S11, the upper wafer W _{U is} evacuated in all of the fields 230a, 230b, and 230c of the upper chuck 230. Similarly, in steps S9 to S11, the lower wafer W _{L is} evacuated in all of the fields 231a and 231b of the lower chuck 231.

In this manner, between steps S10 and S11, in which the horizontal direction and the vertical direction of the upper wafer W _U and the lower wafer W _L are adjusted, the upper wafer W _U is heated to a specific state by the first heating mechanism 242. At the temperature, the lower wafer W _L is heated to a specific temperature by the second heating mechanism 262. Type embodiment of the present aspect, the specific temperature of the wafer W _U W _L and the wafer is heated deg.] C were ~ 100 deg.] C, for example 50, the wafer and the lower wafer W _U W _L system is heated to the same temperature. The specific temperature of 50 ° C to 100 ° C is the temperature found by the inventors and the like, and the temperature of the remaining pure water can be removed as will be described later. Further, if the temperature of the remaining portion of pure water can be removed, the specific temperature is not limited to the present embodiment, and various temperatures can be taken.

Here, in the pure water supplied to the wafers W _U and W _L in steps S2 and S7, the surface W _{U1 of the} upper wafer W _U and the surface W _{L1 of the} lower wafer W _L remain as described above, respectively. The remaining part of pure water. Thus, the remaining portion of pure water can be removed by heating the upper wafer W _U and the lower wafer W _L to a specific temperature in the above manner in steps S10 and S11, respectively. Next, when the upper wafer W _U and the lower wafer W _{L are} heated for a specific time so that the remaining portion of the pure water is completely removed, the heating of the upper wafer W _U and the lower wafer W _L is stopped.

After stopping operation of the first pump 241a, as shown in the first field 21 stops 230a of the first suction tube 240a from the upper wafer W _U evacuated. At this time, in the second field 230b and the third field 230c, the upper wafer W _U is evacuated and held and held. Thereafter, by lowering the press pin 251 of the pressing member 250, the upper wafer W _U is lowered while pressing the center portion of the wafer W _U . At this time, the pressing pin 251 is applied such that the load pin 251 is moved by a load of 70 μm, for example, 200 g, without the upper wafer W _U . Then, the center portion of the upper wafer W _U is brought into contact with and pressed by the center portion of the lower wafer W _L by the pressing member 250 (step S12 of FIG. 18).

After that, the bonding is started between the center portion of the pressed upper wafer W _{U and} the center portion of the lower wafer W _L (the thick line portion in FIG. 21). That is, 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 S6, respectively, and thus, first, a van der Waals force is generated between the surfaces W _U1 and W _L1 ( The intermolecular force) causes the surfaces W _U1 and W _L1 to be joined to each other. Furthermore, 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 S7, respectively, and thus the hydrophilic groups between the surfaces W _U1 and W _L1 are hydrogen bonded (molecules). Inter-force), the surfaces W _U1 , W _L1 are strongly joined to each other.

After that, as shown in FIG. 22, the center portion of the upper wafer W _{U and} the center portion of the lower wafer W _L are pressed by the pressing member 250, the operation of the second vacuum pump 241b is stopped, and the second field 230b is stopped. The upper wafer W _{U is} evacuated from the second suction pipe 240b. After that, the wafer W _U held on the second field 230b is dropped onto the lower wafer W _L . Further, after stopping the operation of the third pump 241c, 230c is stopped in the third field from the third suction tube 240c on the wafer W _U evacuated. In this way from the central portion of the wafer W _U outward circumferential portion, stopping the wafer W _U evacuated, so that the wafer W _U are sequentially dropped and abuts the lower wafer W _L. Next, the above-mentioned surfaces W _U1 and W _L1 are sequentially expanded by the joint of the van der Waals force and the hydrogen bonding. In this way, as shown in FIG. 23, 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 joined (FIG. 18). Step S13).

In this step S13, since the surfaces W _U1 and W _{L1 of the} wafers W _U and W _L are diffusion-bonded, a so-called bonding wave is generated, but in the steps S10 and S11, the upper wafer W _U and the lower wafer W are heated. _L removes the remaining portion of pure water, so that the remaining portion of pure water is not diffused to the outer peripheral portions of the wafers W _U , W _L as before.

Thereafter, the pressing member 250 is raised to the upper chuck 230 as shown in FIG. Further, the lower chuck 231 to stop the suction tube 260a, the wafer W _L 260b performed under vacuum, and stop using the folder plate 231 holding the wafer W _L sucked.

The superposed wafer W _T joined to the upper wafer W _U and the lower wafer W _L is transported to the crystal device 51 by the wafer transfer device 61, and then transferred by the wafer transfer device 22 of the carry-in/out station 2 The cassette C _{T that is} transported to a specific cassette mounting plate 11. After that, the joining process of the series of wafers W _U and W _L is ended.

According to the above embodiment, in the steps S10 and S11, the upper wafer W _U held by the upper chuck 230 and the lower wafer W _L held by the lower chuck 231 are heated to a specific temperature. Using the associated heating can be pure water onto the wafer W _U, W _L surface W _U1, W _L1 from the remaining portion of the surface W _U1, W _L1 removed. Therefore, it is possible to suppress occurrence of bubbles (Edge Void) in the outer peripheral portion between the wafers W _U and W _L without diffusing the remaining portion of pure water to the outer peripheral portions of the wafers W _U and W _L as before. Next, the wafers W _U and W _L can be appropriately joined to each other by van der Waals force and hydrogen bonding (intermolecular force).

Further, in steps S10 and S11, the wafer is held while the upper wafer W _U held by the upper chuck 230 and the lower wafer W _L held by the lower chuck 231 are horizontally aligned in the vertical direction. The heating of W _U and W _L enables efficient heating of the wafers W _U and W _L . Therefore, the wafer bonding process throughput can be improved. Further, the heating of the wafers W _U and W _L may be performed in either of the steps S10 or S11. Further, the heating of the wafers W _U and W _L may be performed in the steps S5 and S9 while the upper wafer W _U is held by the upper chuck 230 and the lower wafer W _L is held by the lower chuck 231.

Further, the engagement system 1, since the engaging means 41 together, and then have the modified wafer W _U, W _L W surface _{Ul, Ll} surface W of the modified apparatus 30, the wafer W _U, W _L W surface _U1, W _L1 and washing of the hydrophilic surface W _U1, W _L1 of the surface hydrophilizing apparatus 40, the wafer W _U can be performed in a system efficiently, _L engagement W. Therefore, the throughput of the wafer bonding process can be further improved.

In the above embodiment, the first heating unit 242 and the second heating unit 262 heat both the upper wafer W _U and the lower wafer W _L , but only the upper wafer W _U or the lower wafer W _L may be used. Any one of them is heated. Next, either one of the first heating mechanism 242 or the second heating mechanism 262 may be omitted. In the relevant case, for example, by heating only the upper wafer W _U and passing a specific time, for example, 30 seconds, the heat of the upper wafer W _U is transferred to the lower wafer W _L , and the lower wafer W _L is also heated. To the same temperature. Further, in the case where only the lower wafer W _{L is} heated, the upper wafer W _U is heated to the same temperature after a certain period of time. In any case, the temperature of the upper wafer W _U and the lower wafer W _L is heated to a specific temperature, so that bubbles can be suppressed from occurring in the outer peripheral portion between the wafers W _U and W _L . W _U and W _L are properly joined to each other. Further, the time during which the upper wafer W _U or the lower wafer W _L is heated is set to a range that does not affect the throughput of the wafer bonding process.

The above embodiments regard patterns, lines 242 by the first heating means and second heating means 262 on the wafer W _U W _L and the wafer was heated to the same temperature, but may be on the wafer and the lower wafer W _U W _{L is} heated to a different temperature. For example, in steps S10 and S11, the temperature difference between the heating temperature of the wafer W _{U and} the heating temperature of the lower wafer W _L is, for example, 10 ° C to 20 ° C, and the upper wafer W _U and the lower wafer W are heated. _L.

Here, there are irregularities on the surface of the upper chuck 230 or the surface of the lower chuck 231, or there are particles or the like on the surface of the upper chuck 230 or the surface of the lower chuck 231, and the upper chuck 230 is placed thereon. The surface or the surface of the lower chuck 231 is not flat. In the related case, when the upper wafer W _U and the lower wafer W _L are bonded, the residual stress at the bonding interface causes skew of the bonded superposed wafer W _T in the vertical direction (distortion).

In this embodiment, since the upper wafer W _U and the lower wafer W _L are heated to different temperatures, the state of the surface of the chuck 230 and the surface of the lower chuck 231 can be matched to make the upper wafer W _U and The lower wafers W _L are each deformed into different shapes. For example, if the upper wafer W _{U is} heated to a higher temperature than the lower wafer W _L , the upper wafer W _U can be expanded more than the lower wafer W _L . Similarly, if the lower wafer W _{L is} heated to a higher temperature than the upper wafer W _U , the lower wafer W _L can be expanded more than the upper wafer W _U . By fitting the curved state of the upper wafer W _U and the lower wafer W _{L to} the surface of the chuck 230 and the surface of the lower chuck 231 in this manner, it is possible to suppress the skew in the vertical direction on the coincident wafer WT. Therefore, in the subsequent steps S12 and S13, the bonding of the upper wafer W _U and the lower wafer W _L can be appropriately performed.

Moreover, the temperature difference between the heating temperature of the upper wafer W _{U and} the heating temperature of the lower wafer W _L is 10 ° C to 20 ° C, which is the temperature found by the inventors and the like, and is capable of superimposing the wafer W _T Fully suppress the temperature of the skew in the vertical direction.

As described in the above embodiment, when at least the upper wafer W _U or the lower wafer W _{L is} heated to a specific temperature of 50 ° C to 100 ° C, occurrence of bubbles in the outer peripheral portion between the wafers W _U and W _L can be suppressed. (Edge Void). Inhibiting the Edge Void in this manner contributes to, for example, an SOI (Silicon On Insulater) wafer in which an insulating film formed of SiO ₂ is formed on the surface. Further, by setting the temperature difference between the heating temperature of the upper wafer W _{U and} the heating temperature of the lower wafer W _L to 10 ° C to 20 ° C, it is possible to suppress the skew of the vertical direction of the superposed wafer W _T (distortion; Distortion) ). In this way, the distortion is suppressed, which is useful for, for example, CMOS (Complementary Metal Oxide Semiconductor) inductive wafer wafer or BSI mode (Back Side Illumination) wafer. Furthermore, in the case where it is required to improve both Edge Void and Distortion, at least the upper wafer W _U or the lower wafer W _{L is} heated to a specific temperature of 50 ° C to 100 ° C, and the heating temperature of the upper wafer W _U is The temperature difference between the heating temperatures of the lower wafers W _L may be set at 10 ° C to 20 ° C.

In the above embodiment, in the steps S10 and S11, the first heating mechanism 242 of the upper chuck 230 heats the upper wafer W _U at a uniform temperature in the wafer surface, but for example, each of the above chucks 230 may be used. The fields 230a, 230b, 230c heat the upper wafer W _{U at} different temperatures. Similarly, the second heating mechanism 262 of the lower chuck 231 heats the lower wafer W _L at a uniform temperature in the wafer surface, but it is also possible to heat the lower crystal at a different temperature for each of the following regions 231a, 231b of the chuck 231, for example. Round W _L . In other cases, the upper surface W _U and the lower wafer W _{L can} be formed into a more appropriate shape by being able to match the surface of the upper chuck 230 and the lower chuck 231. Thereby, the upper wafer W _U and the lower wafer W _{L can be} more appropriately joined. Further, the number of the upper chucks 230 and the lower chucks 231 or the arrangement of the regions to be partitioned can be arbitrarily set without being limited to the present embodiment.

In the above embodiment, the lower chuck 231 is freely movable up and down in the vertical direction by the chuck driving portion 234 and is freely movable in the horizontal direction. However, the upper chuck 230 may be configured to be freely movable in the vertical direction, or It can move freely in the horizontal direction. Further, both the upper chuck 230 and the lower chuck 231 can be freely moved up and down in the vertical direction and can be freely moved in the horizontal direction.

In the bonding system 1 of the above embodiment, after the bonding devices 41 bond the wafers W _U and W _L , the bonded wafer W _{T can} be heated at a specific temperature. By performing the relevant heat treatment on the superposed wafer W _T , the joint interface can be more firmly bonded.

The preferred embodiments of the present invention have been described above with reference to the drawings, but the present invention is not limited to the related examples. It is to be understood that various modifications and changes can be made without departing from the scope of the invention as described in the appended claims. The present invention is not limited to this example, and various aspects can be adopted. The present invention is also applicable to a case where the substrate is an FPD (flat panel display) other than a wafer, or a mask such as a mask for a mask.

230‧‧‧Upper chuck

231‧‧‧ lower chuck

231a, 231b‧‧‧ fields

242‧‧‧1st heating mechanism

243‧‧‧through holes

250‧‧‧Compressed components

251‧‧‧pressure bolt

252‧‧‧Outer tube

253‧‧‧Upper photographic components

260a, 260b‧‧‧ suction tube

261a, 261b‧‧‧ vacuum pump

262‧‧‧2nd heating mechanism

263‧‧‧stop members

264‧‧‧ Lower photographic components

W _U ‧‧‧ Wafer

W _L ‧‧‧ under wafer

230a, 230b, 230c‧‧‧ fields

240a, 240b, 240c‧‧‧ suction tube

241a, 241b, 241c‧‧‧ vacuum pump

Claims (12)

A bonding apparatus that performs bonding of bonded substrates by intermolecular force, and is characterized in that a first holding member that holds a first substrate is sucked under a vacuum, and is provided under the first holding member The second holding member that holds the second substrate is sucked by the vacuum, and at least the first holding member or the second holding member has a heating mechanism that heats at least the first substrate or the second substrate to a specific temperature. The bonding device according to the first aspect of the invention, wherein the first holding member has a first heating mechanism that heats the first substrate, and the second holding member has a second heating mechanism that heats the second substrate; The first heating means and the second heating means are provided with a control unit that controls the heating temperature of the first substrate by the first heating means and the heating temperature of the second substrate by the second heating means to a different temperature. . The bonding apparatus according to the second aspect of the invention, wherein the temperature difference between the heating temperature of the first substrate and the heating temperature of the second substrate is 10 to 20 °C. The bonding apparatus according to any one of claims 1 to 3, wherein the first holding member has a first heating device that heats the first substrate The second holding member has a second heating means for heating the second substrate, and the first heating means and the second heating means are provided to hold the first substrate held by the first holding member and The control unit that controls the second substrate and the second substrate while heating the first substrate and the second substrate while maintaining the position of the second substrate in the second holding member in at least the vertical direction or the horizontal direction. The bonding apparatus according to any one of claims 1 to 3, wherein the specific temperature is 50 ° C to 100 ° C. A bonding system comprising the bonding apparatus of the bonding apparatus according to any one of claims 1 to 3, characterized in that the processing system includes the processing station including the bonding apparatus, and the first substrate, the second substrate, or the first Each of the superposed substrates to which the substrate and the second substrate are bonded are held in a plurality of places, and the first substrate, the second substrate, or the superposed substrate are carried in and out of the processing station; and the processing station has a first substrate or a first substrate a surface modification device for modifying a surface to be joined of a substrate, and a surface hydrophilization device for hydrophilizing a surface of the first substrate or the second substrate modified by the surface modification device, The surface modification device, the surface hydrophilization device, and the bonding device perform the first substrate, the second substrate, or the superposed substrate. In the above-described joining device, the first substrate and the second substrate which are hydrophilized on the surface are joined by the surface hydrophilization device. A bonding method in which a bonding substrate is bonded to each other by an intermolecular force, and is characterized in that a first substrate that is held by the lower surface of the first holding member and a lower portion that is provided under the first holding member are At the time of joining the second substrate held on the upper surface of the second holding member, at least the first substrate or the second substrate is heated to a specific temperature. The joining method according to the seventh aspect of the invention, wherein the first substrate and the second substrate held by the second holding member are joined to each other when the first substrate held by the first holding member is joined to the second substrate held by the second holding member The second substrate is heated together, and the first substrate and the second substrate are heated to different temperatures. The bonding method according to the eighth aspect of the invention, wherein the temperature difference between the heating temperature of the first substrate and the heating temperature of the second substrate is 10 to 20 °C. The bonding method according to any one of claims 7 to 9, wherein the first substrate held by the first holding member and the second substrate held by the second holding member are at least vertical The first substrate and the second substrate are heated together in the direction or the horizontal direction. For example, the joint party described in any of the claims 7 to 9 The method wherein the specific temperature is 50 ° C to 100 ° C. A computer memory medium characterized in that the bonding method described in any one of claims 7 to 9 can be read by a bonding device, and can be read by a program stored in a computer that controls a control unit of the bonding device. Computer memory media.