JP2001267227A - Vibration isolating system, exposure system, and device manufacturing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a vibration isolating system which is compactly mounted with cables and the like and capable of reducing vibrations transmitted to an exposure system through the intermediary of the cables and the like. SOLUTION: A transmitted vibration suppressing relay means 9, which supports the bundled cables 5 that are led out of an exposure system body 1 and their weights and restrains vibrations from being transmitted to the exposure system body 1 through cables 5, is provided at a relay point.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an X
The present invention relates to an anti-vibration system which is preferably used as a constituent unit of a semiconductor exposure apparatus equipped with precision equipment such as a Y stage and eliminates mixing of a sign vibration, and an exposure apparatus and a device manufacturing method using the same.

[0002]

2. Description of the Related Art The role of a vibration isolator is to suppress transmission of floor vibration to a vibration isolator. In recent years, in order to respond to the demand for high precision and high speed of precision equipment mounted on the vibration isolation table, active vibration isolation devices that suppress the vibration on the vibration isolation table by actively operating the actuator tend to be used. It is in. Active anti-vibration devices have superior characteristics compared to passive anti-vibration devices, but they cannot completely shut off the transmission of vibration of the floor on which active anti-vibration devices are installed to the anti-vibration table .

As a vibration transmission path, a mechanism for supporting the vibration isolation table, specifically, a mechanical spring or a viscous element of the mechanism can be cited. In an active vibration isolator, vibration transmitted through a support mechanism that supports the vibration isolation table picks up vibration of the floor with an appropriate vibration detection unit and feeds it through a transmission model of the support mechanism. It can be suppressed by control technology. This is a so-called floor vibration feed forward or ground motion feed forward. By applying this feedforward, transmission of floor vibration to the vibration isolation table can be suppressed to some extent. For example, a maximum of 15 d near the natural frequency of the vibration isolation table
B].

[0004] However, there are floor vibration transmission paths other than those having a clear nature and orientation as a path for transmitting floor vibration, such as a support mechanism for a vibration isolation table. For example, cables to precision equipment or vibration detecting means mounted on the vibration isolation table. This is a general term for electrical wiring and piping for air or a cooling medium. Since these cables are connected from the floor or an object rigidly connected to the floor to precision equipment on the vibration isolation table, they can serve as a vibration transmission path to the vibration isolation table, and the vibration isolation rate (floor of the floor) The rate at which the vibration is transmitted to the anti-vibration table deteriorates the characteristic of which the horizontal axis represents frequency. For example, cables are vibration sources,
For example, when it is in contact with a rotating machine or the like, the vibration is transmitted through cables and the like, and the vibration isolator also vibrates. Such a continuous vibration transmitted to the vibration isolation table can be attenuated only at the suppression ratio indicated by the frequency characteristic of the vibration isolation rate specific to the active vibration isolation device, no matter how much the feedback parameter is adjusted. Moreover, it is difficult to cancel such vibrations by applying a control technique such as the above-described floor vibration feed forward. Of course, when the cables are soft, the transmission of vibration to the vibration isolation table is not at a remarkable level. However, in reality, cables form a thick bundle, which leads to mechanically sufficient rigidity. Therefore, it behaves like a mechanism member for transmitting vibration.

Some proposals have already been made to suppress or reduce the transmission of vibration due to the mounting of such cables. For example, it is disclosed in JP-A-11-82609 (anti-vibration apparatus and exposure apparatus). In this publication, several vibration damping apparatuses and an exposure apparatus having the same are proposed in order to suppress transmission of vibration caused by mounting of cables to the vibration damping table.

FIG. 2 shows an example. In FIG. 1, an exposure apparatus main body 1 is mounted on a pedestal 3
Supported by The exposure apparatus main body 1 includes a vibration isolation table supported by the active vibration isolation device 2 and all the equipment groups and structures mounted on the vibration isolation table. Although 2 is an active anti-vibration device here, it may be a passive anti-vibration device. The cables 5 of the precision equipment group on the exposure apparatus main body 1 and the cables 5 of the active anti-vibration apparatus 2 pass through the main body side fixing means 4,
It is connected to a fixing member 6 provided on the pedestal 3. Usually, the cables 5 are bundled, but in FIG. 2, the cables 5 are dispersed and slackened to eliminate the generation of tension.

FIG. 3 schematically shows a state in which cables and hoses on the exposure apparatus main body are routed as proposed in the above-mentioned publication. As for the route of the cables for driving the electric equipment and the air-conditioning equipment mounted on the exposure apparatus main body, usually, as shown by a broken line 5a, the cables are bundled at one or more places on the exposure apparatus main body 1. In such a case, a route was taken to take it out of the apparatus as it was. In this case, the tension of the cables 5 causes the exposure apparatus body 1
Shaking was a problem. In view of this, the above-mentioned publication proposes mounting the cables 5 so as to be drawn out in such a manner that the rotation center 7 of the exposure apparatus main body 1 exists on the extension of the composite vector of the tension of the cables 5. Reference numeral 8 denotes a vibration damping member added to explicitly indicate that the exposure apparatus main body 1 is supported by the active vibration damping device 2.

Further, the applicant of the present application has also proposed in Japanese Patent Application No. 11-041424 (active vibration isolator) to block transmission of vibration due to mounting of a cable or the like. In this proposal, since the anti-vibration device is active, a large number of vibration detecting means represented by an acceleration sensor are used, but the electric wiring is wireless. Specifically, a signal of a vibration detection head for detecting vibrations at a plurality of positions of the vibration isolation table is transmitted to the receiver by radio waves from the transmitter. The receiver demodulates the signal and outputs an electric signal indicating the vibration of the vibration isolation table. The vibration isolation table is actively controlled by feeding back this electric signal. The power supply to the transmitter is made wireless by adopting, for example, an inductive power supply system. By using the wireless vibration detection means in this way, the electric wiring itself, which has become a vibration transmission path, is eliminated.

As described above, the vibration transmitted to the anti-vibration table via the cables can be significantly reduced if the cables can be mounted as shown in FIG. 2 or FIG. However, regarding FIG. 2, there is a constraint condition that a sufficient mounting space for the routing of cables and the like is secured. In reality, first, a device for satisfying the function of the exposure apparatus is mounted on the main body structure including the anti-vibration table, and the cable or the like 5 is mounted by skillfully using the resulting empty space. of course,
Although there is no technical difficulty in performing mechanical design including mounting, it is actually impossible to implement the mounting shown in FIG. 2 from the viewpoint of realizing a compact exposure apparatus. That is, it cannot be a realistic solution for suppressing the vibration transmitted through the cables 5.

Referring to FIG. 3, there is no technical difficulty in finding the rotation center 7 of the main body structure. And, of course, the mounting of the cables 5 so that the total of the tension vectors of the cables 5 is directed to the center of rotation 7 is also technically necessary to realize this, especially if the design is focused on the mounting of the cables 5 only. There is no difficulty.
However, actually, mounting as shown in FIG. 3 is an ideal theory, and it is almost impossible to route such a cable to an exposure apparatus as an industrial apparatus.

[0011] Further, Japanese Patent Application No. Hei.
With respect to 41424 (active vibration isolator), there is no technical difficulty in realizing this as well. However, since the transmission and reception of signals are performed by radio waves, there is a possibility of causing a new problem of electromagnetic interference, and there is doubt as to whether there is an effect of suppressing vibration that is commensurate with the cost increase due to wireless. . Further, a large number of pipes for supplying and exhausting air to and from the equipment mounted on the vibration isolation table together with the electrical wiring are also paths of vibrations that enter the vibration isolation table. According to Japanese Patent Application No. 11-041424, it is needless to say that vibrations that enter through the latter transmission path cannot be blocked.

Therefore, the present invention proposes a more realistic measure for reducing the vibration that enters the exposure apparatus main body via cables.

[0013]

As described above, the cables for precision instruments and precision measuring instruments mounted on the main body of the exposure apparatus are supported by the passive vibration isolator or the active vibration isolator. Kinds are pulled out. When the active vibration isolator is used to support the exposure apparatus main body, the cables of the vibration isolator itself are also drawn out. With the progress of miniaturization required for the exposure apparatus in recent years, it has been found that the vibration transmitted to the exposure apparatus main body through such cables significantly affects the exposure performance. Of course, if cables are mounted with sufficient space, transmission of vibration can be greatly suppressed. However, cables for an exposure apparatus which is an industrial apparatus should be compactly mounted. Then, the cables are transformed into rigid members, and as a result, the vibration is easily transmitted to the exposure apparatus main body. That is, there is a need to reduce the vibration transmitted to the exposure apparatus main body via the cables after achieving compact mounting of the cables.

[0014]

According to a first aspect of the present invention, there is provided an anti-vibration system for an exposure apparatus, comprising a cable bundled at a relay point on the way from the exposure apparatus main body and its weight. And a transmission vibration suppressing relay means for suppressing vibration transmitted through the cables.

A second vibration isolation system is characterized in that, in the first vibration isolation system, the transmission vibration suppression relay means actively or passively suppresses the vibration.

A third vibration isolation system according to the first or second vibration isolation system is characterized in that it has a passive vibration isolation device or an active vibration isolation device for supporting the exposure apparatus main body on a pedestal. .

A fourth vibration isolation system according to the third vibration isolation system, wherein the cables are coated with a vibration absorbing material or wrapped with the vibration absorbing material on the exposure apparatus main body side and the pedestal side. It is characterized by being.

A fifth vibration isolation system is characterized in that in the fourth vibration isolation system, the vibration absorbing material is a rubber having a rebound resilience coefficient of 20% or less or an ultra-soft rubber having tackiness.

A sixth vibration isolation system is characterized in that, in the fourth vibration isolation system, the vibration absorbing material is urethane whose surface is subjected to a dissolution treatment.

An exposure apparatus according to the present invention is provided with any one of the first to sixth vibration isolation systems. Also,
The device manufacturing method of the present invention includes a step of preparing the exposure apparatus of the present invention, and a step of performing exposure processing using the exposure apparatus while exerting a vibration suppressing function of a transmission vibration suppressing relay unit. It is characterized by.

When the present invention is compared with the conventional example shown in FIG. 2, in the conventional example, in order to minimize the vibration that enters the exposure apparatus main body 1 from the cables 5, the cables 5 are used.
Were mounted apart from each other and loosened. However, this is by no means desirable from an industrial design point of view, where packaging is compact. It is desirable to bundle the cables 5 as much as possible from the viewpoint of effectively utilizing the mounting space.
However, as described above, even if each piece is a soft wiring or pipe, if it is collected and bundled in a large amount, it turns into a rigid member like a mechanical material. Since the rigid member serves as a vibration entry path, it is not preferable to bundle the cables 5 collectively from this side.

On the other hand, in the present invention, priority is given to realizing a practically compact mounting as an industrial device.
That is, cables are bundled up and bundled together as much as possible. In this way, the vibration transmitted through the bundled cables is at a significant level, but is at a level that can be reliably detected by the vibration sensor, and it is easier to take measures to block the vibration. .

That is, although vibrations transmitted to the exposure apparatus main body via individual cables do exist, they are not at such a level as to affect the accuracy of the exposure apparatus. Measures can be taken to reduce or cut off the transmission of vibration for one-to-one cables, and it can be confirmed that the transmission of vibration transmitted from cables decreases only when the sum of them is taken. . If the type of the exposure apparatus is different, it is necessary to perform a complicated operation to take measures to prevent each cable from becoming a vibration transmission path again.

Therefore, according to the present invention, the transmission of vibration from each cable is minute, but by bundling them for compact mounting, a transmission path having a large vibration level is created. Needless to say, if the mounting is performed on the exposure apparatus main body as it is, significant vibration is mixed into the vibration isolation table via these mountings. However, since the level of vibration transmitted through the bundle of cables is large, it is rather easy to take measures to suppress this vibration.

[0025]

FIG. 1 is a perspective view showing a part of an exposure apparatus according to one embodiment of the present invention. As shown in FIG. 1, the exposure apparatus includes a transmission vibration suppressing relay unit 9 that is a cable 5 drawn from the exposure apparatus main body 1 and mechanically relays a rigid bundle. The transmission vibration suppressing relay unit 9 has a function of suppressing vibration transmitted to the exposure apparatus main body 1 via the cables 5 that are rigidly bundled. The transmission vibration suppressing relay means 9 may be passive or active.

As compared with the conventional example of FIG. 2, in the conventional example,
The cables 5 extending from the exposure apparatus main body 1 are mounted with a clearance provided between them, and then are provided with a slack so as not to apply tension to the exposure apparatus main body 1 and guided toward the pedestal 3. I have. On the other hand, in the present embodiment, the cables 5 are
For example, they are gathered and bundled using an appropriate body-side fixing means 14 or the like. Then, the bundle is routed in the direction of the pedestal 3, but is once supported by the transmission vibration suppressing relay means 9 and then routed in the direction of the pedestal 3. The transmission vibration suppressing relay means 9 is a small vibration isolator, which supports the weight of the bundled cables 5 and supports the cables 5 so as not to apply extra tension to the exposure apparatus main body 1. In addition, the transmission vibration suppression relay means 9 has a vibration isolation function for preventing the vibration of the pedestal 3 from entering the exposure apparatus main body 1 using the cables 5 as a transmission medium.

When the transmission vibration suppressing relay means 9 is passive, the bundled cables 5 are simply supported by using an air bellows, and are connected to the exposure apparatus main body 1 via the cables 5. The level of invading vibration can be suppressed. When the transmission vibration suppressing relay means 9 is active, vibration detecting means represented by an acceleration sensor and a speed sensor, and position detecting means represented by an eddy current displacement sensor and an electrostatic displacement sensor are provided. And an actuator such as an air spring, and then performs feedback for driving the actuator in accordance with the outputs of the vibration detecting means and the position detecting means. By using such transmission vibration suppression relay means 9, it is possible to support the bundled cables 5 and to suppress the vibration transmitted through the cables.

By making the transmission vibration suppressing relay unit 9 active, it is possible to function so that the movement of the transmission vibration suppressing relay unit 9 follows the movement of the exposure apparatus main body 1. By interlocking the transmission vibration suppressing relay means 9 with the movement of the exposure apparatus main body 1, the fluctuation of the tension applied to the cables 5 passed between the exposure apparatus main body 1 and the transmission vibration suppressing relay means 9 can be suppressed. As a result, the vibration exerted on the exposure apparatus main body 1 by the routing of the cables 5 can be suppressed.

Further, in order to effectively attenuate the vibration transmitted to the exposure apparatus main body 1 via the cables 5, one or more of the wires and pipes in the cables 5 are provided. A vibration absorbing material is applied to the bundle of bundles, or these are wrapped with the vibration absorbing material. However, the use of rubber, for example, as a vibration absorbing material in order to attenuate vibration is not limited to the semiconductor exposure apparatus to which the present invention is applied, but is also used in general industrial products. In the present embodiment, the mounting site of the vibration absorbing material and its material are specified from a special viewpoint of vibration proof against the vibration of the cables 5 routed from the exposure apparatus main body 1 supported by the vibration isolator 2. .

FIG. 4 shows a mounting portion of the vibration absorbing material. As shown in the drawing, the cables 5 are routed from the exposure apparatus main body 1 toward the pedestal 3, and the vibration absorbing material 10 is provided at a position where the cables 5 are drawn from the exposure apparatus main body 1 and a position where the cables 5 are drawn into the pedestal 3 side. Is installed.

FIG. 5 is a perspective view showing an example of the vibration absorbing material 10. As the vibration absorbing material 10, a vibration absorbing material 10a formed as shown in FIG. 5 is preferably used in order to align the cables 5 and fix the cables. The vibration absorbing material 10a is formed with a dent that encloses the cables 5 and accommodates the cables 5 therein. Furthermore, although not shown, if another vibration absorbing material 10a is prepared and the cables 5 are inserted with scissors, that is, if it is made into a sandwich shape, the effect of vibration reduction is improved. The molded vibration absorbing material 10a is provided with a screw hole 11 for fixing the vibration absorbing material 10a. Using the screw holes 11, the cables 5 can be fixed without play.

As the material of the vibration absorbing material 10, a relatively soft rubber having a rebound resilience coefficient of 20% or less is preferable.
When rubber is used as the material of the vibration absorbing material 10, an ultra-soft rubber having adhesiveness can be preferably used. In the case of ultra-soft rubber, the surface thereof is sticky, so that the cables 5 are wound with the ultra-soft rubber having tackiness, and the cables 5
Can be fixed in place.

As the vibration absorbing material 10, urethane can be used in addition to rubber. However, urethane cannot be used as it is in the exposure apparatus. This is because the urethane may partially fall off and contaminate the environment of the exposure apparatus that should be clean. Therefore, in the present embodiment, urethane is used to suppress the vibration transmitted to the cables, but at this time, the surface of the urethane is modified so that fine drop-off does not occur partially. Specifically, the urethane surface is subjected to a dissolution treatment. The dissolution process results in the formation of a relatively firm skin so that the urethane particles do not peel or fall off. That is,
A clean exposure environment can be maintained.

FIG. 6 shows a vibration absorbing material 10b having a cross section of urethane having a modified surface layer formed by the dissolution treatment.
Is shown. In the figure, 12 is urethane, 13 is a through hole through which cables 5 pass, and 14 is a modified surface layer formed by dissolving the surface of urethane 12.

<Embodiment of Device Manufacturing Method> Next, an embodiment of a device manufacturing method using the above-described exposure apparatus will be described. FIG. 7 shows a flow of manufacturing micro devices (semiconductor chips such as ICs and LSIs, liquid crystal panels, CCDs, thin-film magnetic heads, micro machines, etc.). Step 1
In (Circuit Design), a device pattern is designed. Step 2 is a process for making a mask on the basis of the designed pattern. On the other hand, in step 3 (wafer manufacture), a wafer is manufactured using a material such as silicon or glass. Step 4 (wafer process) is called a pre-process,
An actual circuit is formed on the wafer by lithography using the prepared mask and wafer. The next step 5 (assembly) is called a post-process, and is a process of forming a semiconductor chip using the wafer produced in step 4, and includes processes such as an assembly process (dicing and bonding) and a packaging process (chip encapsulation). including. In step 6 (inspection), inspections such as an operation check test and a durability test of the semiconductor device manufactured in step 5 are performed. Through these steps, a semiconductor device is completed and shipped (step 7).

FIG. 8 shows the wafer process (step 4).
The detailed flow of is shown. Step 11 (oxidation) oxidizes the wafer's surface. Step 12 (CVD) forms an insulating film on the wafer surface. Step 13 (electrode formation) forms electrodes on the wafer by vapor deposition. In step 14 (ion implantation), ions are implanted into the wafer. In step 15 (resist processing), a resist is applied to the wafer. Step 16 (exposure) uses the above-described exposure apparatus to align the circuit pattern of the mask on a plurality of shot areas of the wafer and perform printing exposure. Step 17
In (development), the exposed wafer is developed. Step 18
In (etching), portions other than the developed resist image are scraped off. In step 19 (resist stripping), unnecessary resist after etching is removed. By repeating these steps, multiple circuit patterns are formed on the wafer.

By using the production method of this embodiment, it is possible to produce a large device with good precision and productivity, which was conventionally difficult to produce.

[0038]

The effects of the present invention are as follows. (1) According to the present invention, it is possible to achieve compact mounting by bundling cables and to reduce the vibration that enters the exposure apparatus main body via the cables. (2) As a result of lowering the vibration level on the exposure apparatus main body, exposure accuracy can be improved and productivity can be improved.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a vibration isolator and a semiconductor exposure apparatus using the same according to one embodiment of the present invention.

FIG. 2 is a perspective view showing a method of fixing cables on an exposure apparatus main body according to a conventional example.

FIG. 3 is a schematic view showing a method of routing cables and the like on an exposure apparatus main body according to a conventional example.

FIG. 4 is a perspective view showing a mounting portion of a vibration absorbing material in the apparatus of FIG.

FIG. 5 is a perspective view showing a vibration absorbing material molded as an example of the vibration absorbing material of FIG.

6 is a perspective view showing another example of the vibration absorbing material shown in FIG. 4, which is a vibration absorbing material using urethane whose surface has been subjected to a dissolution treatment.

FIG. 7 is a flowchart showing a device manufacturing method that can use the exposure apparatus of the present invention.

FIG. 8 is a detailed flowchart of a wafer process in FIG. 7;

[Explanation of symbols]

1: exposure apparatus main body, 2: active vibration isolator, 3: pedestal,
4, 14: body side fixing means, 5: cables, 6: fixing member, 7: rotation center, 8: vibration isolating member, 9: transmission vibration suppressing relay means, 10, 10a, 10b: vibration absorbing material, 11:
Screw hole, 12: urethane, 13: through hole, 14: modified surface layer formed by dissolution treatment.

Claims (8)

[Claims] 1. A relay device for supporting a bundled cables and their weight at a relay point in the middle of being pulled out from the exposure apparatus main body, and a transmission vibration suppressing relay unit for suppressing vibration transmitted through the cables. A vibration damping system for an exposure apparatus. 2. The anti-vibration system according to claim 1, wherein said transmission vibration suppressing relay means actively or passively suppresses said vibration. 3. The vibration isolation system according to claim 1, further comprising a passive vibration isolation device or an active vibration isolation device that supports the exposure apparatus main body on a pedestal. 4. The vibration isolation device according to claim 3, wherein the cables are coated with a vibration absorbing material or wrapped with the vibration absorbing material on the exposure apparatus main body side and the pedestal side. system. 5. The vibration absorbing material has a rebound resilience coefficient of 20%.
The vibration isolation system according to claim 4, wherein the vibration isolation system is the following rubber or an ultra-soft rubber having an adhesive property. 6. The vibration damping system according to claim 4, wherein the vibration absorbing material is urethane whose surface is subjected to a dissolution treatment. 7. An exposure apparatus comprising the vibration isolation system according to claim 1. 8. A step of preparing the exposure apparatus according to claim 7,
Using the exposure apparatus to perform an exposure process while exerting a vibration suppressing function of a transmission vibration suppressing relay unit.