Separation method, computer storage medium, and separation system

A superposed wafer is separated to a processing target wafer and a supporting wafer while being heated. Then, an adhesive on a joint surface of the processing target wafer is removed by supplying an organic solvent onto the joint surface of the processing target wafer. Then, an oxide film formed on the predetermined pattern on the joint surface of the processing target wafer is removed by supplying acetic acid to the joint surface of the processing target wafer. Then, the joint surface of the processing target wafer is inspected. Then, based on an inspection result, the adhesive on the joint surface of the processing target wafer is removed and the oxide film formed on the predetermined pattern on the joint surface of the processing target wafer is removed.

CROSS REFERENCE TO RELATED APPLICATION

The present application is a U.S. national stage of PCT/JP2012/071750 filed on Aug. 22, 2012, and is based on Japanese Patent Application No. 2011-197705 filed on Sep. 9, 2011, the disclosures of which are incorporated herein by reference.

TECHNICAL FIELD

The present invention relates to a separation method of separating a superposed substrate into a processing target substrate and a supporting substrate, a computer storage medium, and a separation system executing the separation method.

BACKGROUND ART

In recent years, for example, in a manufacturing process of a semiconductor device, the diameter of a semiconductor wafer (hereinafter, referred to as a “wafer”) increasingly becomes larger. Further, the wafer is required to be thinner in a specific process such as mounting. For example, when a thin wafer with a large diameter is transferred or subjected to polishing as it is, warpage or break can occur in the wafer. Therefore, in order to reinforce the wafer, for example, bonding the wafer to a wafer being a supporting substrate or a glass substrate is performed. The predetermined processing such as polishing and the like are performed on the wafer with the wafer being joined with the supporting substrate as described above, and then the wafer and the supporting substrate are separated.

The separation of the wafer and the supporting substrate is performed using, for example, a separation apparatus. For example, a separation apparatus that directly joins a wafer on which devices are formed to a supporting substrate on which a thermally oxidized film is formed and then separates the wafer is proposed in Patent Document 1. The separation apparatus has, for example, a first holder that holds the wafer, a second holder that holds the supporting substrate, and a nozzle that jets liquid between the wafer and the supporting substrate. Then, this separation apparatus separates the wafer and the supporting substrate by jetting liquid between the joined wafer and supporting substrate, namely, to the joint surfaces of the wafer and the supporting substrate from a nozzle at a jetting pressure greater than the joint strength between the wafer and the supporting substrate, preferably, a jetting pressure twice or greater than the joint strength.

PATENT DOCUMENT

DISCLOSURE OF THE INVENTION

Problems to be Solved by the Invention

Incidentally, methods of joining the wafer and the supporting substrate includes a method of joining the supporting substrate and the wafer with an adhesive intervening between them and so on as well as the method of directly joining the wafer to the supporting substrate on which the thermally oxidized film is formed as disclosed, for example, in Patent Document 1.

When performing the joint using the adhesive, it is necessary to soften the adhesive intervening between the wafer and the supporting substrate in separating the wafer and the supporting substrate. For this reason, when separating the wafer and the supporting substrate, heat processing on the joined wafer and supporting substrate is performed in order to soften the adhesive.

However, heating processing performed on the wafer causes formation of an oxide film on the exposed surface of the wafer, namely, predetermined patterns (devices) exposed on the wafer, in particular, bumps made of metal such as copper. Then, the oxide film may hinder the predetermined patterns from carrying out its function and seriously damage a product.

The present invention has been made in consideration of the above point, and an object thereof is to suppress an oxide film to be formed on a predetermined pattern on the surface of a processing target substrate in separation processing of a processing target substrate and a supporting substrate.

Means for Solving the Problems

To achieve the above object, the present invention is a separation method of separating a superposed substrate in which a processing target substrate and a supporting substrate are joined together with an adhesive, to the processing target substrate and the supporting substrate, the separation method including: a separation step of separating the superposed substrate to the processing target substrate and the supporting substrate while heating the superposed substrate; an adhesive removing step of removing the adhesive on a surface of the processing target substrate thereafter by supplying an organic solvent to the surface of the processing target substrate separated in the separation step; and an oxide film removing step of removing an oxide film formed on a predetermined pattern on the surface of the processing target substrate thereafter by supplying acid to the surface of the processing target substrate from which the adhesive has been removed in the adhesive removing step. Note that the predetermined pattern in the present invention has a bump made of metal such as copper.

According to the present invention, a superposed substrate is separated to a processing target substrate and a supporting substrate in a separation step, an adhesive on the surface of the processing target substrate is removed in a subsequent adhesive removing step, and then acid is supplied to the surface of the processing target substrate in an oxide film removing step. Therefore, even if an oxide film is formed on a predetermined pattern on the surface of the processing target substrate, for example, in the separation step, the oxide film on the predetermined pattern can be removed with the acid supplied in the oxide film removing step. This enables appropriate manufacture of products.

The present invention in another aspect is a computer-readable storage medium storing a program operating on a computer of a control unit controlling a separation system to cause the separation system to execute a separation method of separating a superposed substrate in which a processing target substrate and a supporting substrate are joined together with an adhesive, to the processing target substrate and the supporting substrate, the separation method including: a separation step of separating the superposed substrate to the processing target substrate and the supporting substrate while heating the superposed substrate; an adhesive removing step of removing the adhesive on a surface of the processing target substrate thereafter by supplying an organic solvent to the surface of the processing target substrate separated in the separation step; and an oxide film removing step of removing an oxide film formed on a predetermined pattern on the surface of the processing target substrate thereafter by supplying acid to the surface of the processing target substrate from which the adhesive has been removed in the adhesive removing step.

The present invention in still another aspect is a separation system that separates a superposed substrate in which a processing target substrate and a supporting substrate are joined together with an adhesive, to the processing target substrate and the supporting substrate, including: a separation apparatus that separates the superposed substrate to the processing target substrate and the supporting substrate while heating the superposed substrate; a solvent supplying unit that removes the adhesive on a surface of the processing target substrate by supplying an organic solvent to the surface of the processing target substrate separated by the separation apparatus; and an acid supplying unit that removes an oxide film formed on a predetermined pattern on the surface of the processing target substrate by supplying acid to the surface of the processing target substrate from which the adhesive has been removed by the solvent supplying unit.

Effect of the Invention

According to the present invention, it is possible to suppress an oxide film formed on a predetermined pattern on the surface of a processing target substrate in separation processing of a processing target substrate and a supporting substrate.

BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, embodiments of the present invention will be described.FIG. 1is a plan view illustrating the outline of a configuration of a separation system1according to this embodiment.

In the separation system1, a superposed wafer T as a superposed substrate in which a processing target wafer W as a processing target substrate and a supporting wafer S as a supporting substrate are joined together with an adhesive G as illustrated inFIG. 2is separated into the processing target wafer W and the supporting wafer S. Hereinafter, in the processing target wafer W, the surface to be joined with the supporting wafer S via the adhesive G is referred to as a “joint surface WJ” and the surface opposite to the joint surface WJis referred to as “a non-joint surface WN.” Similarly, in the supporting wafer S, the surface to be joined with the processing target wafer W via the adhesive U is referred to as a “joint surface SJ” and the surface opposite to the joint surface SJis referred to as “a non-joint surface SN.” Note that the processing target wafer W is a wafer which will be a product, and a plurality of devices (predetermined patterns) have been formed, for example, on the joint surface WJ. The predetermined patterns have bumps made of metal such as copper. Further, in the processing target wafer W, for example, the non-joint surface WNhas been subjected to polishing to be thinned (for example, with a thickness of 50 μm to 100 μm). The supporting wafer S is a wafer which has the same diameter as that of the processing target wafer W and supports the processing target wafer W. Note that a case of using a wafer as the supporting substrate will be described in this embodiment, but other substrates such as, for example, a glass substrate and the like may be used.

The separation system1has, as illustrates inFIG. 1, a configuration in which a transfer-in/out station2into/from which cassettes CW, CS, CTcapable of housing a plurality of processing target wafers W, a plurality of supporting wafers S, and a plurality of superposed wafers T respectively are transferred from/to the outside, a separation processing station3including various processing and treatment apparatuses that perform predetermined processing and treatment on the processing target wafer W, the supporting wafer S, and the superposed wafer T, and an interface station5that delivers the processing target wafer W to/from a post-processing station4adjacent to the separation processing station3, are integrally connected.

The transfer-in/out station2and the separation processing station3are arranged side by side in an X-direction (a top-bottom direction inFIG. 1). Between the transfer-in/out station2and the separation processing station3, a wafer transfer region6is formed. The interface station5is located on a Y-direction negative direction side (a left direction side inFIG. 1) of the separation processing station3. On an X-direction positive direction side (an upper direction side inFIG. 1) of the interface station5, an inspection apparatus7that inspects the processing target wafer W before being delivered to the post-processing station4is disposed. Further, on the opposite to the inspection apparatus7across the interface station5, namely, on an X-direction negative direction side (a lower direction side inFIG. 1) of the interface station5, a post-inspection cleaning station8that cleans the joint surface WJand the non-joint surface WNof the processing target wafer W after inspection and reverses the front and rear surfaces of the processing target wafer W is disposed.

In the transfer-in/out station2, a cassette mounting table10is provided. On the cassette mounting table10, a plurality of, for example, three cassette mounting plates11are provided. The cassette mounting plates11are arranged side by side in a line in a Y-direction (a right-left direction inFIG. 1). On these cassette mounting plates11, the cassettes CW, CS, CTcan be mounted when the cassettes CW, CS, CTare transferred in/out from/to the outside of the separation system1. As described above, the transfer-in/out station2is configured to be capable of holding the plurality of processing target wafers W, the plurality of supporting wafers S, and the plurality of superposed wafers T. Note that the number of cassette mounting plates11is not limited to this embodiment but can be arbitrarily determined. Further, the plurality of superposed wafers T transferred into the transfer-in/out station2have been subjected to inspection in advance and discriminated between a superposed wafer T including a normal processing target wafer W and a superposed wafer T including a defective processing target wafer W.

In the wafer transfer region6, a first transfer apparatus20is disposed. The first transfer apparatus20has, for example, a transfer arm that is movable, for example, in the vertical direction, the horizontal directions (the X-direction, the Y-direction), and around the vertical axis. The first transfer apparatus20can move in the wafer transfer region6and transfer the processing target wafer W, the supporting wafer S, the superposed wafer T between the transfer-in/out station2and the separation processing station3.

The separation processing station3has a separation apparatus30that separates the superposed wafer T into the processing target wafer W and the supporting wafer S. On the Y-direction negative direction side (the left direction side inFIG. 1) of the separation apparatus30, a first cleaning apparatus31that cleans the separated processing target wafer W is disposed. Between the separation apparatus30and the first cleaning apparatus31, a second transfer apparatus32is provided. Further, on the Y-direction positive direction side (the right direction side inFIG. 1) of the separation apparatus30, a second cleaning apparatus33that cleans the separated supporting wafer S is disposed. As described above, in the separation processing station3, the first cleaning apparatus31, the second transfer apparatus32, the separation apparatus30, and the second cleaning apparatus33are arranged side by side in this order from the interface station5side.

The inspection apparatus7inspects the presence or absence of a residue of the adhesive G on the processing target wafer W separated by the separation apparatus30, and the presence or absence of a residue of an oxide film formed on the predetermined patterns, in particular, the bumps on the joint surface WJof the processing target wafer W. Further, the post-inspection cleaning station8cleans the processing target wafer W for which a residue of the adhesive G and a residue of the oxide film have been checked in the inspection apparatus7. The post-inspection cleaning station8has a joint surface cleaning apparatus40that cleans the joint surface WJof the processing target wafer W, a non-joint surface cleaning apparatus41that cleans the non-joint surface WNof the processing target wafer W, and a reversing apparatus42that reverses the front and rear surfaces of the processing target wafer W. The joint surface cleaning apparatus40, the non-joint surface cleaning apparatus41, and the reversing apparatus42are arranged side by side in the Y-direction from the post-processing station4side.

In the interface station5, a third transfer apparatus51which is movable on a transfer path50that extends in the Y-direction is provided. The third transfer apparatus51is also movable in the vertical direction and around the vertical axis (in a θ-direction), and thus can transfer the processing target wafer W between the separation processing station3, the post-processing station4, the inspection apparatus7, and the post-inspection cleaning station8.

Note that in the post-processing station4, predetermined post-processing is performed on the processing target wafer W separated in the separation processing station3. As the predetermined post-processing, for example, processing of mounting the processing target wafer W, processing of performing inspection of electric characteristics of the devices on the processing target wafer W, processing of dicing the processing target wafer W into chips are performed.

Next, the configuration of the above-described separation apparatus30will be described. The separation apparatus30has a processing container100in which a plurality of devices are housed as illustrated inFIG. 3. In the side surface of the processing container100, a transfer-in/out port (not illustrated) for the processing target wafer W, the supporting wafer S, and the superposed wafer T is formed, and an opening/closing shutter (not illustrated) is provided at the transfer-in/out port. Note that the processing container100in this embodiment is composed of for example, a thin plate made of stainless steel or the like and does not hermetically close the inside thereof, but the processing container100is not limited in structure to this embodiment, but may be an airtight container which can hermetically close the inside thereof.

At the bottom surface of the processing container100, an exhaust port101exhausting the atmosphere in the processing container100is formed. An exhaust pipe103communicating with an exhaust apparatus102such as, for example, a vacuum pump is connected to the exhaust port101.

Inside the processing container100, a first holding unit110that suction-holds the processing target wafer W by its lower surface, and a second holding unit111that mounts and holds the supporting wafer S on its upper surface are provided. The first holding unit110is provided above the second holding unit111and disposed to face the second holding unit111. In other words, inside the processing container100, the separation processing is performed on the superposed wafer T with the processing target wafer W arranged on the upper side and the supporting wafer S arranged on the lower side.

For the first holding unit110, for example, a porous chuck is used. The first holding unit110has a main body unit120in a flat plate shape. On the lower surface side of the main body unit120, a porous121being a porous body is provided. The porous121has, for example, substantially the same diameter as that of the processing target wafer W and is in abutment with the non-joint surface WNof the processing target wafer W. Note that as the porous121, for example, silicon carbide is used.

Further, a suction space122is formed inside the main body unit120and above the porous121. The suction space122is formed, for example, in a manner to cover the porous121. To the suction space122, a suction pipe123is connected. The suction pipe123is connected to a negative pressure generating apparatus (not illustrated) such as, for example, a vacuum pump. Then, the non-joint surface WNof the processing target wafer is sucked from the suction pipe123via the suction space122and the porous121so that the processing target wafer W is suction-held by the first holding unit110.

Further, inside the main body unit120and above the suction space122, a heating mechanism124heating the processing target wafer W is provided. For the heating mechanism124, for example, a heater is used.

On the upper surface of the first holding unit110, a supporting plate130that supports the first holding unit110is provided. The supporting plate130is supported on the ceiling surface of the processing container100. Note that the supporting plate130in this embodiment may be omitted so that the first holding unit110is supported in abutment with the ceiling surface of the processing container100.

Inside the second holding unit111, a suction pipe140for suction-holding the supporting wafer S is provided. The suction pipe140is connected to a negative pressure generating apparatus (not illustrated) such as, for example, a vacuum pump.

Further, inside the second holding unit111, a heating mechanism141heating the supporting wafer S is provided. For the heating mechanism141, for example, a heater is used.

Below the second holding unit111, a moving mechanism150that moves the second holding unit111and the supporting wafer S in the vertical direction and the horizontal direction is provided. The moving mechanism150has a vertical moving unit151that moves the second holding unit111in the vertical direction and a horizontal moving unit152that moves the second holding unit111in the horizontal direction.

The vertical moving unit151has a supporting plate160that supports the lower surface of the second holding unit111, a driving unit161that raises and lowers the supporting plate160to cause the first holding unit110and the second holding unit111to approach to and separate from each other in the vertical direction, and supporting members162that support the supporting plate160. The driving unit161has, for example, a ball screw (not illustrated) and a motor (not illustrated) that turns the ball screw. Further, the supporting members162are configure to be capable of expansion and contraction in the vertical direction, and provided, for example, at three locations between the supporting plate160and a later-described supporting body171.

The horizontal moving unit152has a rail170that extends along an X-direction (a right-left direction inFIG. 3), the supporting body171attached to the rail170, and a driving unit172that moves the supporting body171along the rail170. The driving unit172has, for example, a ball screw (not illustrated) and a motor (not illustrated) that turns the ball screw.

Note that below the second holding unit111, raising and lowering pins (not illustrated) for supporting the superposed wafer T or the supporting wafer S from below and raising and lowering it are provided. The raising and lowering pins are configured to be able to pass through through holes (not illustrated) formed in the second holding unit111and project from the upper surface of the second holding unit111.

Next, the configuration of the above-described first cleaning apparatus31will be described. The first cleaning apparatus31has a treatment container180as illustrated inFIG. 4. In a side surface of the treatment container180, a transfer-in/out port (not illustrated) for the processing target wafer W is formed, and an opening/closing shutter (not illustrated) is provided at the transfer-in/out port.

At a central portion inside the treatment container180, a porous chuck190that mounts and rotates the processing target wafer W thereon is provided. The porous chuck190has a main body unit191in a flat plate shape and a porous192being a porous body provided on the upper surface side of the main body unit191. The porous192has, for example, substantially the same diameter as that of the processing target wafer W and is in abutment with the non-joint surface WNof the processing target wafer W. Note that as the porous192, for example, silicon carbide is used. A suction pipe (not illustrated) is connected to the porous192and sucks the non-joint surface WNof the processing target wafer W from the suction pipe via the porous192and thereby can suction-hold the processing target wafer W on the porous chuck190.

Below the porous chuck190, a chuck driving unit193equipped with, for example, a motor is provided. The porous chuck190can rotate at a predetermined speed by means of the chuck driving unit193. Further, the chuck driving unit193is provided with a raising and lowering driving source such as, for example, a cylinder so that the porous chuck190can freely rise and lower.

Around the porous chuck190, a cup194is provided as a recovery unit that receives and recovers liquid splashing or dropping from the processing target wafer W. A later-described solvent drain pipe195that drains a waste solution of an organic solvent and a later-described acetic acid drain pipe196that drains a waste solution of an acetic acid are connected to the lower surface of the cup194. Note that an exhaust pipe (not illustrates) that vacuums and exhausts the atmosphere in the cup194is also connected to the lower surface of the cup194.

As illustrated inFIG. 5, on an X-direction negative direction (a downward direction inFIG. 5) side of the cup194, a rail200that extends along a Y-direction (a right-left direction inFIG. 5) is formed. The rail200is formed, for example, from a Y-direction negative direction (a left direction inFIG. 5) side outer position of the cup194to a Y-direction positive direction (a right direction inFIG. 5) side outer position. On the rail200, for example, two arms201,202are attached.

On the first arm201, a solvent nozzle203as a solvent supplying unit that supplies a solvent for the adhesive G being the cleaning solution for the adhesive G, for example, an organic solvent onto the processing target wafer W is supported as illustrated inFIG. 4andFIG. 5. The first arm201is movable on the rail200by means of a nozzle driving unit204illustrated inFIG. 5. Thus, the solvent nozzle203can move from a waiting section205provided at the Y-direction positive direction side outer position of the cup194to a position above a central portion of the processing target wafer W in the cup194, and further move in the diameter direction of the processing target wafer W above the processing target wafer W. Further, the first arm201can freely rise and lower by means of the nozzle driving unit204to be able to adjust the height of the solvent nozzle203.

For the solvent nozzle203, for example, a two-fluid nozzle is used. To the solvent nozzle203, a supply pipe210that supplies the organic solvent to the solvent nozzle203is connected as illustrated inFIG. 4. The supply pipe210communicates with a solvent supply source211that stores the organic solvent therein. Along the supply pipe210, a supply equipment group212is provided which includes a valve, a flow regulator and so on that control the flow of the organic solvent. Further, a supply pipe213that supplies an inert gas, for example, a nitrogen gas to the solvent nozzle203is connected to the solvent nozzle203. The supply pipe213communicates with a gas supply source214that stores the inert gas therein. Along the supply pipe213, a supply equipment group215is provided which includes a valve, a flow regulator and so on that control the flow of the inert gas. Then, the organic solvent and the inert gas are mixed in the solvent nozzle203and supplied from the solvent nozzle203to the processing target wafer W. Note that the mixture of the organic solvent and the inert gas is sometimes referred to simply as an “organic solvent” hereinafter.

On the second arm202, an acetic acid nozzle220as an acetic acid supplying unit that supplies acetic acid that is acid in a liquid state is supported. The second arm202is movable on the rail200by means of a nozzle driving unit221illustrated inFIG. 5. Thus, the acetic acid nozzle220can move from a waiting section222provided at the Y-direction negative direction side outer position of the cup194to a position above a central portion of the processing target wafer W in the cup194, and further move in the diameter direction of the processing target wafer W above the processing target wafer W. Further, the second arm202can freely rise and lower by means of the nozzle driving unit221to be able to adjust the height of the acetic acid nozzle220.

To the acetic acid nozzle220, a supply pipe223that supplies the acetic acid to the acetic acid nozzle220is connected as illustrated inFIG. 4. The supply pipe223communicates with an acetic acid supply source224that stores acetic acid with a concentration of 100% therein and a pure water supply source225that stores pure water therein. Along the supply pipe223, a mixer226is provided which mixes the acetic acid supplied from the acetic acid supply source224and the pure water supplied from the pure water supply source225. In this mixer226, the acetic acid with a concentration of 100% and the pure water are mixed to generate a solution of acetic acid with a predetermined concentration, for example, a concentration of 70%. Note that the solution of acetic acid with a concentration of 70% made by mixing the acetic acid with a concentration of 100% and the pure water is sometimes referred to simply as “acetic acid.” Further, along the supply pipe223, a supply equipment group227that includes a valve, a flow regulator and so on that control the flow of the acetic acid is provided downstream of the mixer226.

Incidentally, below the porous chuck190, raising and lowering pins (not illustrated) for supporting the processing target wafer W from below and raising and lowering it may be provided. In this case, the raising and lowering pins are configured to be able to pass through through holes (not illustrated) formed in the porous chuck190and project from the upper surface of the porous chuck190. Then, in place of raising and lowering the porous chuck190, the raising and lowering pins are raised or lowered to deliver the processing target wafer W to/from the porous chuck190.

Note that the aforementioned joint surface cleaning apparatus40and non-joint surface cleaning apparatus41in the post-inspection cleaning station8have the same configuration as that of the first cleaning apparatus31, and therefore the description thereof is omitted. Further, the acetic acid nozzles220in the joint surface cleaning apparatus40and the non-joint surface cleaning apparatus41constitute another acid supplying unit in the present invention. Since the predetermined patterns being the devices are not formed on the non-joint surface WNof the processing target wafer W in this embodiment, no oxide film is formed on the bumps on the non-joint surface WN. However, in the case where the oxide film is formed on the non-joint surface WNitself, the acetic acid nozzles220and its accompanying members221to227in the non-joint surface cleaning apparatus41are useful in removing the oxide film. Further, the predetermined patterns being the devices are sometimes formed also on the non-joint surface of the processing target wafer in a specific product. In this case, the acetic acid nozzles220and its accompanying members221to227in the non-joint surface cleaning apparatus41are useful in removing the oxide film formed on the bumps of the predetermined patterns.

Further, the configuration of the second cleaning apparatus33is substantially the same as the configuration of the above-described first cleaning apparatus31. In the second cleaning apparatus33, a spin chuck230is provided as illustrated inFIG. 6in place of the porous chuck190of the first cleaning apparatus31. The spin chuck230has a horizontal upper surface, and a suction port (not illustrated) for sucking, for example, the supporting wafer S is provided in the upper surface. By suction through the suction port, the supporting wafer S can be suction-held on the spin chuck230. The second cleaning apparatus33has a configuration in which the acetic acid nozzle220and its accompanying members221to227in the first cleaning apparatus31are omitted. Further, to the cup194of the second cleaning apparatus33, an exhaust pipe231that vacuums and exhausts the atmosphere in the cup194is connected while the acetic acid drain pipe196in the first cleaning apparatus31is omitted. The other configuration of the second cleaning apparatus33is the same as that of the above-described first cleaning apparatus31, and therefore the description thereof is omitted.

Incidentally, in the second cleaning apparatus33, a back rinse nozzle (not illustrated) that jets a cleaning solution toward the rear surface of the supporting wafer S, namely, the non-joint surface SNmay be provided below the spin chuck230. The cleaning solution jetted from the hack rinse nozzle cleans the non-joint surface SNof the supporting wafer S and the outer peripheral portion of the supporting wafer S.

Next, the configuration of the above-described second transfer apparatus32will be described. The second transfer apparatus32has a Bernoulli chuck240that holds the processing target wafer W as illustrated inFIG. 7. The Bernoulli chuck240is supported by a supporting arm241. The supporting arm241is supported by a first driving unit242. By means of the first driving unit242, the supporting arm241can turn around the horizontal axis and expand and contract in the horizontal direction. Below the first driving unit242, a second driving unit243is provided. By means of the second driving unit243, the first driving unit242can rotate around the vertical axis and rise and lower in the vertical direction.

Note that the third transfer apparatus51has the same configuration as that of the above-described second transfer apparatus32, and therefore the description thereof is omitted. However, the second driving unit232of the third transfer apparatus51is attached to the transfer path50illustrated inFIG. 1so that the third transfer apparatus51is movable on the transfer path50.

Next, the configuration of the aforementioned reversing apparatus42will be described. The reversing apparatus42has a processing container250housing a plurality of devices therein as illustrated inFIG. 8. In a side surface of the processing container250, a transfer-in/out port (not illustrated) is formed for transferring in/out the processing target wafer W by the third transfer apparatus51, and an opening/closing shutter (not illustrated) is provided at the transfer-in/out port.

At the bottom surface of the processing container250, an exhaust port260that exhausts the atmosphere in the processing container250is formed. To the exhaust port260, an exhaust pipe262is connected which communicating with an exhaust apparatus261such as a vacuum pump.

Inside the processing container250, a first holding unit270that holds the processing target wafer W on its lower surface and a second holding unit271that holds the processing target wafer W on its upper surface are to provided. The first holding unit270is provided above the second holding unit271and disposed to face the second holding unit271. The first holding unit270and the second holding unit271have substantially the same diameter as that of, for example, the processing target wafer W. For the first holding unit270and the second holding unit271, Bernoulli chucks are used. This enables each of the first holding unit270and the second holding unit271to hold the whole one surface of the processing target wafer W in a non-contact manner.

On the upper surface of the first holding unit270, a supporting plate272that supports the first holding unit270is provided. Note that the supporting plate272in this embodiment may be omitted so that the first holding unit270is supported in abutment with the ceiling surface of the processing container250.

Below the second holding unit271, a moving mechanism280that moves the second holding unit271in the vertical direction is provided. The moving mechanism280has a supporting plate281that supports the lower surface of the second holding unit271and a driving unit282that raises and lowers the supporting plate281to cause the first holding unit270and the second holding unit271to approach to and separate from each other in the vertical direction. The driving unit282is supported by a supporting body283provided at the bottom surface of the processing container250. Further, a supporting member284that supports the supporting plate281is provided on the upper surface of the supporting body283. The supporting member284is configured to be capable of expansion and contraction in the vertical direction and to be able to freely expand and contact when the driving unit282raises and lowers the supporting plate281.

Next, the configuration of the aforementioned inspection apparatus7will be described. The inspection apparatus7has a processing container290as illustrated inFIG. 9andFIG. 10. In a side surface of the processing container290, a transfer-in/out port (not illustrated) for the processing target wafer W is formed, and an opening/closing shutter (not illustrated) is provided at the transfer-in/out port.

Inside the processing container290, a porous chuck300that holds the processing target wafer W thereon is provided. The porous chuck300has a main body unit301in a flat plate shape and a porous302being a porous body provided on the upper surface side of the main body unit301. The porous302has, for example, substantially the same diameter as that of the processing target wafer W and is in abutment with the non-joint surface WNof the processing target wafer W. Note that as the porous302, for example, silicon carbide is used. A suction pipe (not illustrated) is connected to the porous302and sucks the non-joint surface WNof the processing target wafer W from the suction pipe via the porous302and thereby can suction-hold the processing target wafer W on the porous chuck300.

Below the porous chuck300, a chuck driving unit303is provided. The porous chuck300can rotate by means of the chuck driving unit303. Further, the chuck driving unit303is attached to the top of a rail304provided at the bottom surface inside the processing container290and extending along the Y-direction. By means of the chuck driving unit303, the porous chuck300can move along the rail304. More specifically, the porous chuck300can move between a delivery position P1 for transferring in/out the processing target wafer W to/from the outside of the processing container290and an alignment position P2 where the position of a notch portion of the processing target wafer W is adjusted.

At the alignment position P2, a sensor305is provided which detects the position of the notch portion of the processing target wafer W held on the porous chuck300. The chuck driving unit303rotates the porous chuck300while the sensor305is detecting the position of the notch portion, and thereby can adjust the position of the notch portion of the processing target wafer W.

On a side surface on the alignment position P2 side in the processing container290, an imaging apparatus310is provided. As the imaging apparatus310, for example, a wide-angle CCD camera is used. Near the middle of the upper portion of the processing container290, a half mirror311is provided. The half mirror311is provided at a position facing the imaging apparatus310, and inclined at 45 degrees from the vertical direction. An illumination apparatus312that can change in illuminance is provided above the half mirror311, and the half mirror311and the illumination apparatus312are fixed to the upper surface of the processing container290. Further, the imaging apparatus310, the half mirror311, and the illumination apparatus312are provided above the processing target wafer W held on the porous chuck300. The illumination from the illumination apparatus312passes through the half mirror311and is applied downward. Accordingly, reflection light from an object existing in an irradiation area thereof is reflected off the half mirror311and is taken into the imaging apparatus310. In other words, the imaging apparatus310can capture an image of the object existing in the illumination area. The captured image of the processing target wafer W is then outputted to a later-described control unit350. The control unit350inspects the presence or absence of a residue of the adhesive G on the processing target wafer W and the presence or absence of a residue of an oxide film formed on the bumps on the joint surface WJof the processing target wafer W.

In the above separation system1, the control unit350is provided as illustrated inFIG. 1. The control unit350is, for example, a computer and has a program storage unit (not illustrated). In the program storage unit, a program is stored which controls the processing of the processing target wafer W, the supporting wafer S, and the superposed wafer T in the separation system1. Further, the program storage unit also stores a program for controlling the operation of the driving system such as the above-described various processing and treatment apparatuses and transfer apparatuses to implement the later-described separation processing in the separation system1. Note that the program may be the one that is stored, for example, in a computer-readable storage medium H such as a computer-readable hard disk (HD), flexible disk (FD), compact disk (CD), magneto-optical disk (MO), or memory card, and installed from the storage medium H into the control unit350.

Next, the separation processing method of the processing target wafer W and the supporting wafer S performed using the separation system1configured as described above will be described.FIG. 11is a flowchart illustrating an example of main steps of the separation processing.

First, a cassette CThousing a plurality of superposed wafers T, an empty cassette CW, and an empty cassette CSare mounted on the predetermined cassette mounting plates11in the transfer-in/out station2. The superposed wafer T in the cassette CTis taken out by the first transfer apparatus20and transferred to the separation apparatus30in the separation processing station3. In this event, the superposed wafer T is transferred with the processing target wafer W arranged on the upper side and the supporting wafer S arranged on the lower side.

The superposed wafer T transferred in the separation apparatus30is suction-held on the second holding unit111. Thereafter, the second holding unit111is raised by the moving mechanism150so that the superposed wafer T is held sandwiched by the first holding unit110and the second holding unit111as illustrated inFIG. 12. In this event, the non-joint surface WNof the processing target wafer W is suction-held by the first holding unit110, and the non-joint surface SNof the supporting wafer S is suction-held by the second holding unit111.

Thereafter, the heating mechanisms124,141heat the superposed wafer T to a predetermine temperature, for example, 200° C. Then, the adhesive G in the superposed wafer T becomes softened.

Subsequently, while the heating mechanisms124,141are heating the superposed wafer T to keep the softened state of the adhesive G, the second holding unit111and the supporting wafer S are moved by the moving mechanism150in the vertical direction and the horizontal direction, namely, obliquely downward as illustrated inFIG. 13. Then, as illustrated inFIG. 14, the processing target wafer W held by the first holding unit110and the supporting wafer S held by the second holding unit111are separated as illustrated inFIG. 14(step A1inFIG. 11).

In this event, the second holding unit111moves 100 μm in the vertical direction and moves 300 mm in the horizontal direction. Incidentally, in this embodiment, the thickness of the adhesive G in the superposed wafer T is, for example, 30 μm to 40 μm and the height of the bumps formed on the joint surface WJof the processing target wafer W is, for example, 20 μm. Accordingly, the distance between the devices (predetermined patterns) on the processing target wafer W and the supporting wafer S is minute. Hence, for example, when the second holding unit111is moved only in the horizontal direction, the devices and the supporting wafer S can come into contact with each other, whereby the devices may be damaged. In this regard, moving the second holding unit111in the horizontal direction and also in the vertical direction as in this embodiment can prevent the contact between the devices and the supporting wafer S to suppress damage to the devices. Note that the ratio between the moving distance in the vertical direction and the moving distance in the horizontal direction of the second holding unit111is set based on the height of the bumps on the processing target wafer W.

Note that when separating the superposed wafer T into the processing target wafer W and the supporting wafer S as described above, the atmosphere inside the processing container100has been exhausted, but a minimal amount of oxygen remains. Even if the remaining oxygen is minimal, an oxide film is formed on the predetermined patterns on the joint surface WJof the processing target wafer W, in particular, on the bumps because the processing target wafer W is heated.

Thereafter, the processing target wafer W separated in the separation apparatus30is transferred by the second transfer apparatus32to the first cleaning apparatus31. Here, the transfer method of the processing target wafer W by the second transfer apparatus32will be described.

The supporting arm241of the second transfer apparatus32is extended to locate the Bernoulli chuck240below the processing target wafer W held by the first holding unit110as illustrated inFIG. 15. Thereafter, the Bernoulli chuck240is raised, and the suction of the processing target wafer W from the suction pipe123at the first holding unit110is stopped. Then, the processing target wafer W is delivered from the first holding unit110to the Bernoulli chuck240. Thereafter, the Bernoulli chuck240is lowered to a predetermined position. Note that the processing target wafer W is held by the Bernoulli chuck240in a manner not in contact therewith. Therefore, the processing target wafer W is held with the devices on the joint surface WJof the processing target wafer W being never damaged. Note that the second holding unit111is moved to a position facing the first holding unit110in this event.

Next, as illustrated inFIG. 16, the supporting arm241of the second transfer apparatus32is turned to move the Bernoulli chuck240to above the porous chuck190in the first cleaning apparatus31and reverse the Bernoulli chuck240to thereby direct the processing target wafer W downward. In this event, the porous chuck190is raised to a position upper than the cup194and kept waiting. Thereafter, the processing target wafer W is delivered from the Bernoulli chuck240to the porous chuck190and suction-held.

After the processing target wafer W is suction-held on the porous chuck190in this manner, the porous chuck190is lowered to a predetermined position. Subsequently, the first arm201moves the solvent nozzle203at the waiting section205to a position above the central portion of the processing target wafer W. Thereafter, while the porous chuck190is rotating the processing target wafer W, the organic solvent is supplied from the solvent nozzle203to the joint surface WJof the processing target wafer W. The supplied organic solvent is diffused over the entire joint surface WJof the processing target wafer W by the centrifugal force, whereby the adhesive G on the joint surface WJof the processing target wafer W is removed (step A2inFIG. 11).

After the adhesive G on the joint surface WJof the processing target wafer W is removed, the solvent nozzle203is moved from above the central portion of the processing target wafer W to the waiting section205, and the acetic acid nozzle220at the waiting section205is moved by the second arm202to a position above the central portion of the processing target wafer W. Thereafter, while the processing target wafer W is being rotated, the acetic acid is supplied from the acetic acid nozzle220to the joint surface WJof the processing target wafer W. The supplied acetic acid is diffused by the centrifugal force over the entire joint surface WJof the processing target wafer W to remove the oxide film formed on the bumps on the joint surface WJof the processing target wafer W (step A3inFIG. 11).

In step A3, the acetic acid with a concentration of 70% is supplied to the joint surface WJof the processing target wafer W. As a result of earnest study of the inventors, it is found that even if the acetic acid with a concentration of 70% is used as described above, the oxide film on the bumps can be sufficiently removed by adjusting the supply flow rate and the supply period of the acetic acid, the rotation period of the processing target wafer W and the like. For example, it is found that by supplying the acetic acid at 0.31 lit/min for 180 to 240 seconds and rotating the processing target wafer W for 60 seconds, the oxide film on the bumps can be removed. Further, the acetic acid with a low concentration is used as described above, so that even if the acetic acid is supplied onto patterns except the bumps, such as patterns having no oxide formed thereon, damage to the patterns can be avoided. Note that the concentration of the acetic acid is not limited to 70% but may be a predetermined concentration or more with which the acetic acid can remove the oxide film on the bumps.

Here, the plurality of superposed wafers T transferred in the transfer-in/out station2have been subjected to inspection in advance as described above and discriminated between a superposed wafer T including a normal processing target wafer W and a superposed wafer T including a defective processing target wafer W.

The normal processing target wafer W separated from the normal superposed wafer T is cleaned at its joint surface WJin steps A2and A3and then transferred with the non-joint surface WNdirected downward, by the third transfer apparatus51to the inspection apparatus7. Note that the transfer of the processing target wafer W by the third transfer apparatus51is substantially the same as the above-described transfer of the processing target wafer W by the second transfer apparatus32, and therefore the description thereof is omitted.

The processing target wafer W transferred to the inspection apparatus7is held on the porous chuck300at the delivery position P1. Subsequently, the chuck driving unit303moves the porous300to the alignment position P2. Then, while the sensor305is detecting the position of the notch portion of the processing target wafer W, the chuck driving unit303rotates the porous chuck300. Then, the position of the notch portion of the processing target wafer W is adjusted, whereby the processing target wafer W is located in a predetermined orientation.

Thereafter, the chuck driving unit303moves the porous300from the alignment position P2 to the delivery position P1. Then, illumination is applied from the illumination apparatus312to the processing target wafer W when the processing target wafer W passes under the half mirror311. The light by the illumination reflected off the top of the processing target wafer W is taken into the imaging apparatus310, so that an image of the joint surface WJof the processing target wafer W is captured in the imaging apparatus310. The captured image of the joint surface WJof the processing target wafer W is outputted to the control unit350, and the control unit350inspects the presence or absence of a residue of the adhesive G on the joint surface WJof the processing target wafer W and the presence or absence of a residue of the oxide film formed on the bumps on the joint surface WJof the processing target wafer W (step A4inFIG. 11).

If a residue of the adhesive G and a residue of the oxide film are verified in the inspection apparatus7, the processing target wafer W is transferred by the third transfer apparatus51to the joint surface cleaning apparatus40in the post-inspection cleaning station8, and the adhesive G on the joint surface WJis removed in the joint surface cleaning apparatus40(step A5inFIG. 11). Further, the oxide film on the bumps on the joint surface WJis also removed in the joint surface cleaning apparatus40(step A6inFIG. 11). Note that steps A5and A6are the same as those of the above-described steps A2and A3respectively, and the description thereof is omitted. Further, for example, if it is verified that there is no residue of the adhesive G in the inspection apparatus7, step A5may be omitted. Similarly, if it is verified that there is no residue of the oxide film in the inspection apparatus7, step A6may be omitted.

After the joint surface WJis cleaned, the processing target wafer W is transferred by the third transfer apparatus51to the reversing apparatus42, and its front and rear surfaces are reversed, namely, reversed in the top-bottom direction by the reversing apparatus42(step A7inFIG. 11). The reversing method of the processing target wafer W by the reversing apparatus42will be described here.

The processing target wafer W having the joint surface WJcleaned in the joint surface cleaning apparatus40is transferred to the reversing apparatus42with the joint surface WJbeing held by the Bernoulli chuck240of the third transfer apparatus51as illustrated inFIG. 17. Then, the processing target wafer W is delivered to the second holding unit271of the reversing apparatus42with the joint surface WJdirected upward, and the entire non-joint surface WNof the processing target wafer W is held by the second holding unit271.

Then, the Bernoulli chuck240of the third transfer apparatus51is retracted from above the second holding unit271, and the second holding unit271is raised, in other words, made to approach to the first holding unit270by the supporting body283as illustrated inFIG. 18. Then, the joint surface WJof the processing target wafer W is held by the first holding unit270and the holding of the processing target wafer W by the second holding unit271is stopped to deliver the processing target wafer W to the first holding unit270. Thus, the processing target wafer W is held by the first holding unit270with the non-joint surface WNdirected downward as illustrated inFIG. 19.

Thereafter, the second holding unit271is lowered to separate the first holding unit270and the second holding unit271, and the retracted Bernoulli chuck240of the third transfer apparatus51is then turned around the horizontal axis. Then, with the Bernoulli chuck240directed upward, the Bernoulli chuck240is located below the first holding unit270. Then, the Bernoulli chuck240is raised, and the holding of the processing target wafer W by the first holding unit270is stopped concurrently therewith. Thereby the processing target wafer W having the joint surface WJheld by the Bernoulli chuck240when transferred into the joint surface cleaning apparatus40is brought into a state in which the non-joint surface WNis held by the Bernoulli chuck240as illustrated inFIG. 20. In other words, the processing target wafer W is brought into a state in which the surface of the processing target wafer held by the Bernoulli chuck240is changed from front to rear. Thereafter, the Bernoulli chuck240holding the non-joint surface WNof the processing target wafer W is retracted from the reversing apparatus42.

Note that if a residue of the adhesive G and a residue of the oxide film are not verified in the inspection apparatus7, the processing target wafer W is subjected to the reversal in the reversing apparatus42without being transferred to the joint surface cleaning apparatus40. The reversing method is the same as the above-described method.

Thereafter, the Bernoulli chuck240of the third transfer apparatus51holding the processing target wafer W is turned around the horizontal axis to reverse the processing target wafer W in the top-bottom direction. Then, the processing target wafer W with the non-joint surface WNdirected upward is transferred by the Bernoulli chuck240again to the inspection apparatus7, and the non-joint surface WNis inspected (step A8inFIG. 11). Then, when the contamination such as particles or an oxide film is verified on the non-joint surface WN, the processing target wafer W is transferred by the third transfer apparatus51to the non-joint surface cleaning apparatus41, and the non-joint surface WNis cleaned by the non-joint surface cleaning apparatus41(step A9inFIG. 11). Further, the oxide film on the non-joint surface WNis also removed in the non-joint surface cleaning apparatus41(step A10inFIG. 11). Note that since the predetermined patterns are not formed on the non-joint surface WNof the processing target wafer W, the oxide film is not formed on the bumps of the predetermined patterns in this embodiment. However, if the oxide film is formed on the non-joint surface WNitself, step A10is performed. Further, steps A9and A10are the same as the above-described step A2and step A3, and therefore the description thereof is omitted. Further, for example, if it is verified that there is no contamination such as particles and an oxide film in the inspection apparatus7, steps A9and A10may be omitted.

Then, the cleaned processing target wafer W is transferred by the third transfer apparatus51to the post-processing station4. Note that if a residue of the adhesive G and a residue of the oxide film are not verified in the inspection apparatus7, the processing target wafer W is transferred to the post-processing station4as it is without being transferred to the non-joint surface cleaning apparatus41.

Thereafter, predetermined post-processing is performed on the processing target wafer W in the post-processing station4(step A11inFIG. 11). In this manner, the processing target wafer W becomes a product.

On the other hand, the defective processing target wafer W separated from the defective superposed wafer T is cleaned at its joint surface WJin steps A2and A3and then transferred by the first transfer apparatus20to the transfer-in/out station2. Thereafter, the defective processing target wafer W is transferred from the transfer-in/out station2to the outside and collected (step A12inFIG. 11).

While the above-described steps A1to A12are being performed on the processing target wafer W, the supporting wafer S separated in the separation apparatus30is transferred by the first transfer apparatus20to the second cleaning apparatus33. Then, in the second cleaning apparatus33, the adhesive on the joint surface SJof the supporting wafer S is removed, whereby the joint surface SJis cleaned (step A13inFIG. 11). Note that the cleaning of the supporting wafer S in step A13is the same as the removal of the adhesive G on the processing target wafer W in the above-described step A2, and therefore the description thereof is omitted.

Thereafter, the supporting wafer S whose joint surface SJhas been cleaned is transferred by the first transfer apparatus20to the transfer-in/out station2. Then, the supporting wafer S is transferred from the transfer-in/out station2to the outside and collected (step A14inFIG. 11). Thus, a series of separation processing of the processing target wafer W and the supporting wafer S ends.

According to this embodiment, after the superposed wafer T is separated into the processing target wafer W and the supporting wafer S in step A1, the adhesive G on the joint surface WJof the processing target wafer W is removed in subsequent step A2, the acetic acid is supplied to the joint surface WJof the processing target wafer W in step A3. Therefore, even if an oxide film is formed on the bumps on the joint surface WJof the processing target wafer W in step A1, the oxide film can be removed with the acetic acid supplied in step A3. This enables appropriate manufacture of products.

Further, when the inspection of the joint surface WJseparated in step A4is performed and it is verified that the oxide film remains on the bumps on the joint surface WJof the processing target wafer W, the acetic acid is supplied to the joint surface WJof the processing target wafer W in subsequent step A6to remove the oxide film. Therefore, the oxide film on the bumps on the joint surface WJof the processing target wafer W can be more surely removed.

Further, since the acetic acid with a concentration of 70% is used in removing the oxide film in steps A3, A6, A10, the oxide film can be sufficiently removed. In addition, the acetic acid with such a low concentration is used as described above, so that even if the acetic acid is supplied onto the patterns having no oxide formed thereon, damage to the patterns can be avoided.

Further, since the acetic acid is used in removing the oxide film in steps A3, A6, A10, high safety can be secured. Further, since the acetic acid is inexpensive, the manufacturing cost of products can be reduced.

In the above embodiment, after removal of the oxide film on the bumps on the joint surface WJof the processing target wafer W in step A3, a rust inhibitor may be further applied to the joint surface WJof the processing target wafer W.

As illustrated inFIG. 21, a rust inhibitor nozzle400as a rust inhibitor supplying unit that applies the rust inhibitor to the joint surface WJof the processing target wafer W held by the porous chuck190is provided in the first cleaning apparatus31. To the rust inhibitor nozzle400, a supply pipe401is connected. The supply pipe401communicates with a rust inhibitor supply source402that stores the rust inhibitor therein. Further, along the supply pipe401, a supply equipment group403is provided which includes a valve, a flow regulator and so on that control the flow of the rust inhibitor. Note that, for example, an acidic water-soluble polymer is used as the rust inhibitor.

The rust inhibitor nozzle400is supported by a third arm404. The third arm404is movable on the rail200by means of a nozzle driving unit405. Thus, the rust inhibitor nozzle400can more between a waiting section406which is provided between the cup194and the waiting section222, and a waiting section407which is provided between the cup194and the waiting section205, and further move in the diameter direction of the processing target wafer W above the processing target wafer W in the cup194. Further, the third arm404can freely rise and lower by means of the nozzle driving unit405to be able to adjust the height of the rust inhibitor nozzle400. Note that the other configuration of the first cleaning apparatus31is the same as the configuration of the first cleaning apparatus31in the above embodiment, and therefore the description thereof will be omitted.

In this case, after the acetic acid is supplied from the acetic acid nozzle220to the joint surface WJof the processing target wafer W to remove the oxide film on the bumps on the joint surface WJof the processing target wafer W in step A3, the rust inhibitor nozzle400at the waiting section406is moved by the third arm404to a position above the central portion of the processing target wafer W. Thereafter, the rust inhibitor is supplied from the rust inhibitor nozzle400to the joint surface WJof the processing target wafer W while the processing target wafer W is being rotated. The supplied rust inhibitor is diffused over the entire joint surface WJof the processing target wafer W by the centrifugal force. Note that the other steps A1, A2, A4to A14are the same as steps A1, A2, A4to A14in the above embodiment, and therefore the description thereof will be omitted.

According to this embodiment, the rust inhibitor is applied to the joint surface WJof the processing target wafer W to protect the joint surface WJfrom rust after the oxide film on the bumps is removed, so that it is possible to surely prevent an oxide film from being formed on the humps even when transfer in the atmosphere and predetermined treatments are then performed on the processing target wafer W.

Note that the joint surface cleaning apparatus40and the non-joint surface cleaning apparatus41may have the same configuration as that of the above-described first cleaning apparatus31and supply the rust inhibitor to the joint surface WJof the processing target wafer W after steps A6and A10.

In the first cleaning apparatus31in the above embodiment, a waste solution of the acetic acid may be neutralized by an alkali solution. For the alkali solution, a weak alkali solution is used and, for example, a solution of caustic soda (sodium hydroxide) is used.

As illustrated inFIG. 22, on the side surface of the cup194of the first cleaning apparatus31, an alkali supply pipe410is provided as an alkali supplying unit that supplies the alkali solution to the inside of the cup194. A plurality of alkali supply pipes410may be provided. Further, the alkali supply pipe410communicates with an alkali supply source411that stores the alkali solution therein. Further, along the alkali supply pipe410, a supply equipment group412is provided which includes a valve, a flow regulator and so on that control the flow of the alkali solution. Note that the other configuration of the first cleaning apparatus31is the same as the configuration of the first cleaning apparatus31in the above embodiment, and therefore the description thereof will be omitted.

In this case, the acetic acid supplied onto the processing target wafer W in step A3splashes from the processing target wafer W and is recovered by the cup194. Further, the alkali solution is supplied from the alkali supply pipe410to the inside of the cup194. Then, the waste solution of the acetic acid inside the cup194is neutralized by the alkali solution and discharged from the acetic acid drain pipe196. Note that the other steps A1, A2, A4to A14are the same as steps A1, A2, A4to A14in the above embodiment, and therefore the description thereof will be omitted.

The above-described alkali supply pipe410may be provided in the acetic acid drain pipe196or may be provided in a waste solution tank (not illustrated) to which the acetic acid drain pipe196is connected and in which the waste solution of the acetic acid is stored.

Further, as illustrated inFIG. 23, an alkali nozzle420may be provided as an alkali supplying unit that supplies the alkali solution onto the processing target wafer W held by the porous chuck190in the first cleaning apparatus31. To the alkali nozzle420, a supply pipe421is connected. The supply pipe421communicates with an alkali supply source422that stores the alkali solution therein. Further, along the alkali supply pipe421, a supply equipment group423is provided which includes a valve, a flow regulator and so on that control the flow of the alkali solution.

The alkali nozzle420is supported by a fourth arm424. The fourth arm424is movable on the rail200by means of a nozzle driving unit425. Thus, the alkali nozzle420can move between a waiting section426which is provided between the cup194and the waiting section222, and a waiting section427which is provided between the cup194and the waiting section205, and further move in the diameter direction of the processing target wafer W above the processing target wafer W in the cup194. Further, the fourth arm424can freely rise and lower by means of the nozzle driving unit425to be able to adjust the height of the alkali nozzle420. Note that the other configuration of the first cleaning apparatus31is the same as the configuration of the first cleaning apparatus31in the above embodiment, and therefore the description thereof will be omitted.

In this case, after the acetic acid is supplied from the acetic acid nozzle220to the joint surface WJof the processing target wafer W to remove the oxide film on the bumps on the joint surface WJof the processing target wafer W in step A3, the alkali nozzle420at the waiting section426is moved by the fourth arm424to a position above the central portion of the processing target wafer W. Thereafter, the alkali solution is supplied from the alkali nozzle420to the joint surface WJof the processing target wafer W while the processing target wafer W is being rotated. The supplied alkali solution is diffused over the entire joint surface WJof the processing target wafer W by the centrifugal force and scatters in the cup194. Then, the alkali solution neutralizes the acetic acid remaining on the processing target wafer W or the waste solution of the acetic acid recovered inside the cup194. The neutralized waste solution of the acetic acid is drained from the acetic acid drain pipe196. Note that the other steps A1, A2, A4to A14are the same as steps A1, A2, A4to A14in the above embodiment, and therefore the description thereof will be omitted.

In any of the embodiments, the waste solution of the acetic acid is neutralized by the alkali solution, thereby making it easy to handle the waste solution of the acetic acid when it is disposed of. It is also possible to secure high safety.

Note that the joint surface cleaning apparatus40and the non-joint surface cleaning apparatus41may have the same configuration as that of the above-described first cleaning apparatus31and neutralize the waste solution of the acetic acid in steps A6and A10.

Though the acetic acid in the liquid state is supplied from the acetic acid nozzle220to the joint surface WJof the processing target wafer W in the first cleaning apparatus31in the above embodiment, acetic acid in a gaseous state may be supplied to the joint surface WJof the processing target wafer W.

As illustrated inFIG. 24, an acetic acid gas supply pipe430as an acid supplying unit that supplies the acetic acid gas in the gaseous state to the joint surface WJof the processing target wafer W is provided on the ceiling surface of the treatment container180and above the processing target wafer W held on the spin chuck190in the first cleaning apparatus31. To the acetic acid gas supply pipe430, an acetic acid supply source431that supplies the acetic acid gas is connected. Further, along the acetic acid gas supply pipe430, a supply equipment group432is provided which includes a valve, a flow regulator and so on that control the flow of the acetic acid gas.

The acetic acid supply source431stores the acetic acid in the liquid state therein. Further, to the acetic acid supply source431, a nitrogen gas supply pipe433is connected which supplies a nitrogen gas into the acetic acid supply source431. In the acetic acid supply source431, supply of the nitrogen gas thereinto causes the acetic acid in the liquid state to vaporize to generate the acetic acid gas. This acetic acid gas is supplied to the acetic acid gas supply pipe430using the nitrogen gas as a carrier gas.

The first cleaning apparatus31has a configuration without the acetic acid nozzle220and its accompanying members221to227in the first cleaning apparatus31in the above embodiment. Further, in the first cleaning apparatus31, the acetic acid drain pipe196in the first cleaning apparatus31in the above embodiment is omitted, and an exhaust pipe434that vacuums and exhausts the atmosphere inside the cup194is connected. Note that the other configuration of the first cleaning apparatus31is the same as the configuration of the first cleaning apparatus31in the above embodiment, and therefore the description thereof will be omitted.

In this case, the acetic acid is supplied from the acetic acid gas supply pipe430to the joint surface WJof the processing target wafer W in step A3to remove the oxide film on the bumps on the joint surface WJof the processing target wafer W. Then, the acetic acid gas after removing the oxide film is exhausted from the exhaust pipe424. Note that the other steps A1, A2, A4to A14are the same as steps A1, A2, A4to A14in the above embodiment, and therefore the description thereof will be omitted.

Also in this embodiment, even if the oxide film is formed on the bumps on the joint surface WJof the processing target wafer W in step A1, the oxide film can be removed with the acetic acid supplied in step A3. This enables appropriate manufacture of products. In addition, it is possible to omit the waste solution disposal of the acetic acid and therefore secure high safety and reduce the manufacturing cost.

Note that the joint surface cleaning apparatus40and the non-joint surface cleaning apparatus41may have the same configuration as that of the above-described first cleaning apparatus31and remove the oxide film on the bumps on the joint surface WJof the processing target wafer W using the acetic acid in the gaseous state in steps A6and A10.

Though acetic acid is used as the acid in the first cleaning apparatus31, the joint surface cleaning apparatus40, and the non-joint surface cleaning apparatus41in the above embodiment, another acid may be used. For example, sulfuric acid, hydrochloric acid, nitric acid or the like may be used.

Further, in the case where the oxide film on the bumps on the joint surface WJof the processing target wafer W can be surely removed in the first cleaning apparatus31, the acetic acid nozzles220and their accompanying members221to227in the joint surface cleaning apparatus40and the non-joint surface cleaning apparatus41may be omitted. Further, in this case, the inspection apparatus7may be omitted.

Though the two-fluid nozzles are used as the solvent nozzles203in the first cleaning apparatus31, the second cleaning apparatus33, the joint surface cleaning apparatus40, and the non-joint surface cleaning apparatus41in the above embodiment, the form of the solvent nozzle203is not limited to that in this embodiment, but various nozzles can be used. For example, as the solvent nozzle203, a nozzle body made by uniting a nozzle that supplies an organic solvent and a nozzle that supplies an inert gas, or a spray nozzle, a jet nozzle, a mega-sonic nozzle may be used. Further, to improve the throughput of the cleaning treatment, for example, a cleaning solution heated to 80° C. may be supplied.

Further, a nozzle that supplies IPA (isopropyl alcohol) may be provided in addition to the solvent nozzle203in the first cleaning apparatus31, the second cleaning apparatus33, the joint surface cleaning apparatus40, and the non-joint surface cleaning apparatus41. In this case, after the processing target wafer W or the supporting wafer S is cleaned with the cleaning solution from the solvent nozzle203, the cleaning solution on the processing target wafer W or the supporting wafer S is replaced with IPA. This more surely cleans the joint surface WJ, SJof the processing target wafer W or the supporting wafer S.

Though the second holding unit111is moved in the vertical direction and the horizontal direction in the separation apparatus30in the above embodiment, the first holding unit110may be moved in the vertical direction and the horizontal direction. Alternatively, both of the first holding unit110and the second holding unit111may be moved in the vertical direction and the horizontal direction.

Though the second holding unit111is moved in the vertical direction and the horizontal direction in the above separation apparatus30, the second holding unit111may be moved only in the horizontal direction and the moving speed of the second holding unit111may be changed. Specifically, the moving speed when the second holding unit111starts to move may be set low and then gradually accelerated. The reason why the moving speed of the second holding unit111is set low is that at the time when the second holding unit111starts to move, the contact area between the processing target wafer W and the supporting wafer S is large and the devices on the processing target wafer W are susceptible to the adhesive G. Thereafter, as the contact area between the processing target wafer W and the supporting wafer S becomes smaller, the devices on the processing target wafer W become less susceptible to the adhesive G, and therefore the moving speed of the second holding unit111is gradually accelerated. Also in this case, it is possible to prevent the devices and the supporting wafer S from coming into contact with each other to suppress the damage to the devices.

Though the second holding unit111is moved in the vertical direction and the horizontal direction in the separation apparatus30in the above embodiment, the second holding unit111may be moved only in the horizontal direction, for example, when the distance between the devices on the processing target wafer W and the supporting wafer S is large enough. In this case, it is possible to avoid the contact between the devices and the supporting wafer S and facilitate the control of the movement of the second holding unit111. Further, the second holding unit111may be moved only in the vertical direction to separate the processing target wafer W and the supporting wafer S, or an outer peripheral end portion of the second holding unit111may be moved only in the vertical direction to separate the processing target wafer W and the supporting wafer S.

In the separation apparatus30in the above embodiment, a cover (not illustrated) that covers the processing space between the first holding unit110and the second holding unit111may be provided. In this case, the processing space is brought into an atmosphere of an inert gas, thereby making it possible to suppress formation of the oxide film on the predetermined patterns on the joint surface WJof the processing target wafer W even when the processing target wafer W is subjected to heat processing.

Further, a porous plate (not illustrated) that is movable in the horizontal direction following the second holding unit111and supplies an inert gas from a plurality of pores may be provided in the separation apparatus30in the above embodiment. In this case, at the time when moving the second holding unit111to separate the superposed wafer T the inert gas is supplied to the joint surface WJof the processing target wafer W which has been exposed by the separation while the porous plate is being moved following the second holding unit111. This makes it possible to suppress formation of the oxide film on the predetermined patterns on the joint surface WJof the processing target wafer W even when the processing target wafer W is subjected to heat processing.

Note that though the processing target wafer W and the supporting wafer S are separated with the processing target wafer W arranged on the upper side and the supporting wafer S arranged on the lower side in the separation apparatus30in the above embodiment, the upper and lower arrangement of the processing target wafer W and the supporting wafer S may be reversed.

Further, the configuration of the inspection apparatus7is not limited to that in the above embodiment. The inspection apparatus7can take various configurations as long as it can capture an image of the processing target wafer W and inspect the presence or absence of a residue of the adhesive G and the presence or absence of a residue of the oxide film on the processing target wafer W.

A temperature adjusting device (not illustrated) cooling the processing target wafer W heated in the separation apparatus30down to a predetermined temperature may be provided in the separation system1in the above embodiment. In this case, since the temperature of the processing target wafer W is adjusted to an appropriate temperature, subsequent processing can be more smoothly performed.

Next, another embodiment will be described. Note that the description of the same portions as those in the above embodiment will be omitted. In this embodiment, the same processing is performed in the separation system1not on the above-described superposed wafer T but on a superposed wafer T in the state that a protecting member for protecting the superposed wafer T from breakage, for example, a dicing frame440is attached to the superposed wafer T as illustrated inFIG. 25. Note thatFIG. 25is a longitudinal sectional view of the superposed wafer T attached to the dicing frame440.FIG. 26is a plan view of the dicing frame440and the superposed wafer T illustrated inFIG. 25seen from below. The dicing frame440is an annular plate material. As illustrated inFIG. 25, an adhesive tape441with the adhesive surface directed downward is bonded to the top surface of the dicing frame440. To the adhesive surface, the non-joint surface WNof the processing target wafer W is joined. Carrying out the present invention with the dicing frame440joined in this manner makes it possible to prevent breakage of the processing target wafer W in the separation system1. Note that though the dicing frame440has the annular configuration in this embodiment, the outer peripheral portion of the dicing frame440may take various forms such as an almost rectangular shape.

In this case, it is only necessary to house the superposed wafer T and the dicing frame440joined in advance in the cassette CTand mount the cassette CTon the cassette mounting plate11. Alternatively, it is only necessary to connect an external apparatus (not illustrated) and the separation system1and join the superposed wafer T and the dicing frame440in the external apparatus, and then perform processing thereon in the separation system1. Alternatively, a processing apparatus that joins the superposed wafer T and the dicing frame440together may be provided in the separation system1.

When the processing is performed in the separation apparatus30, the supporting wafer S is separated into a state that the processing target wafer W and the dicing frame440are joined together. It is preferable to perform the processing with the processing target wafer W and the dicing frame440kept joined together until the end of the processing in the separation system1. Then, the processing target wafer W and the dicing frame440are housed into the cassette CWwhile being kept joined together. This makes it possible to prevent breakage of the processing target wafer W. Then, after the processing in the separation system1ends, the processing target wafer W and the dicing frame440may be separated in the external apparatus (not illustrated).

Though the case of performing processing on the processing target wafer W in the post-processing station4into a product has been described in the above embodiment, the present invention is also applicable to the case where a processing target wafer used, for example, in the three-dimensional integration technique is separated from a supporting wafer. Note that the three-dimensional integration technique is the technique responding to the demand for higher integration of semiconductor devices in recent years, which three-dimensionally stacks a plurality of highly integrated semiconductor devices instead of arranging the highly integrated semiconductor devices within a horizontal surface. Also in this three-dimensional integration technique, the reduction in thickness of the processing target wafers to be stacked is required, and the processing target wafer is joined with the supporting wafer and subjected to the predetermined processing.

Preferred embodiments of the present invention have been described above with reference to the accompanying drawings, but the present invention is not limited to the embodiments. It should be understood that various changes and modifications are readily apparent to those skilled in the art within the scope of the technical spirit as set forth in claims, and those should also be covered by the technical scope of the present invention. The present invention is not limited to the embodiments but can take various forms. The present invention is also applicable to the case where the substrate is a substrate other than the wafer, such as an FPD (Flat Panel Display), a mask reticle for a photomask or the like.

EXPLANATION OF CODES