JPH10106939A - Exposing system and substrate carrying method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the cloudiness of the optical members such as a mirror, a lens and the like by removing the gaseous chemical substance in the path, where the substrate to be exposed is delivered between an exposing device and the substrate processing device such as a coater, a developer and the like with which light exposure and development are automated. SOLUTION: A wafer transfer path wc is shut off from the outside air by a stepper which is a part of a semiconductor exposing device, and an exhaust device es, to be used to remove the chemical substance intruded from a developper, is provided on the path wc. A chemical filter device 60 is a chemical substance removing device which is composed of a chemical filter, having a dust removing filter uf and activated charcoal as the base material, a chemical filter cf formed by ion-replacement resin and a blower 17. Outside air is purified by a dust removing filter uf and a chemical filter cf, and the purified air is blown against the wafer transfer path wc located between a developper 50 and the main body of the exposing device.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to an exposure system for applying a photosensitive agent to a substrate to be exposed such as a wafer or a glass substrate, exposing the substrate, and developing the substrate, and a substrate transfer method suitable for such a system. Especially IC and L
The present invention relates to an exposure system including a semiconductor exposure apparatus and a coater / developer used in a manufacturing process of a semiconductor element such as an SI, and a substrate transfer method in the system.

[0002]

2. Description of the Related Art First, a conventional semiconductor manufacturing apparatus will be described. FIG. 5 shows the components of a conventional stepper and a coater / coater.
FIG. 2 is a configuration diagram illustrating an outline of an overall arrangement of developers. In the figure, reference numeral 2 (2, 2 ′) denotes a photo original (hereinafter referred to as a reticle), and 3 (3, 3 ′, 3 ″) denotes a wafer.

When the luminous flux emitted from the light source device 4 illuminates the reticle 2 through the illumination optical system 5, the pattern on the reticle 2 can be transferred to the photosensitive layer on the wafer 3 by the projection lens 6. The light source device 4 includes, for example, an ultrahigh-pressure mercury lamp as a light source and optical members such as an elliptical mirror and a lens, and also includes, for example, an excimer laser as a light source and an optical system that forms a laser beam into a predetermined shape. The reticle 2 is supported by a reticle stage 7 for holding and moving the reticle 2. The wafer 3 is exposed while being vacuum-sucked by the wafer chuck 91. The wafer chuck 91 can be moved in each axis direction by the wafer stage 9. Above the reticle 2, a reticle optical system 81 for detecting the amount of displacement of the reticle 2 is arranged.
An off-axis microscope 82 is arranged above the wafer stage 9 and adjacent to the projection lens 6. The off-axis microscope 82 is a monocular microscope that handles non-exposure light (white light), and its main role is to detect the relative position between the internal reference mark and the alignment mark on the wafer 3.

A reticle library 20 and a wafer carrier elevator 30 which are peripheral devices are arranged adjacent to the stepper body, and necessary reticles and wafers are transferred to the stepper body by a reticle transfer device 21 and a wafer transfer device 31. .

For air conditioning of the stepper body and peripheral devices,
Chamber 1 is used. The chamber 1 mainly includes an air conditioner room 10 for adjusting the temperature of air and a minute foreign substance 3.
And a booth 14 for isolating the environment of the apparatus from the outside.

In the chamber 1, air whose temperature has been adjusted by a cooler 15 and a reheater 16 in an air conditioner room 10 is supplied into a booth 14 by a blower 17 through an air filter g.

[0007] The air supplied to the booth 14 is again taken into the air conditioner room 10 from the return port ra, and is supplied to the chamber 1.
Circulates inside. Normally, this chamber 1 is not strictly a complete circulation system, and about 10% of the circulating air amount is blown by an outside air inlet oa provided in the air conditioner room 10 in order to keep the inside of the booth 14 always at a positive pressure. Has been introduced through. Of course, as described later, the booth 1 for cooling the light source device 4 and the like.
When a part of the air in 4 is forcibly exhausted to factory equipment, an amount of outside air is added which is in proportion to the exhaust flow rate. Booth 1
The reason for keeping the pressure 4 positive is to prevent minute foreign substances from entering the booth 14 from outside the booth 14 through the minute gaps in the booth 14. In this way, the chamber 1 makes it possible to keep the temperature of the environment where the apparatus is placed constant and keep the air clean. In addition, the light source device 4 is provided with an intake port ea in preparation for cooling of the ultra-high pressure mercury lamp and generation of toxic gas at the time of laser abnormality, and a part of the air in the booth 14 passes through the light source device 4 to the air conditioner room 10. The air is forcibly exhausted to factory equipment via a dedicated exhaust fan provided.

Although this stepper may be used alone, a coater 40 for applying a photosensitive agent onto the wafer 3 is used.
A device called a developer 50 for developing the exposed wafer and the exposed wafer is disposed adjacent to the stepper, and the transfer of the wafer 3 between the stepper and the coater 40 or the developer 50 is performed by a robot, whereby the photosensitive agent on the wafer 3 is transferred. Coating,
It is often used in so-called in-line to automate exposure and development. Conventionally, in this in-line, an opening is provided in the adjacent wall surfaces of the chamber 1 surrounding the stepper body and the coater 40 or the developer 50, and the wafer 3 is transferred through this opening.

[0009]

However, in the above-mentioned conventional example, when the apparatus is operated for a long period of time, as a result, optical members such as mirrors and lenses disposed in the light source device 4 and the illumination optical system 5 become inoperative. There is a problem that the device becomes cloudy and the illuminance of the exposure light deteriorates, thereby lowering the yield of the apparatus. Investigation of the location where this fogging occurred revealed that each was an optical member disposed close to a light emitting portion of the light source or a position where the energy intensity of the light collected by the optical system was high.

In addition, Japanese Patent Application Laid-Open Nos. 4-128702 and
It has been found that many of this cloudy material is ammonium sulfate (NH ₄ ) ₂ SO ₄ , as also disclosed in US Pat. The source of these substances is HMD, which is used as an adhesion enhancer between the wafer and the photosensitive agent.
Ammonia vapor (NH ₃ ) generated from S (hexamethyldisilazane) or concrete in a building, sulfuric acid (H ₂ SO ₄ ) used to peel off a photosensitive agent on a wafer
And so on. Further, since the above-mentioned HMDS is used in the coater, when the pressure in the coater is higher than the pressure in the chamber surrounding the stepper in-line, the HMDS vapor enters the atmosphere on the stepper side through the wafer transfer openings of each other. there's a possibility that. By the way, there is an invention according to Japanese Patent Application Laid-Open No. Hei 7-130613 for gaseous chemical substances entering the chamber from the outside air inlet oa, but no measures are taken against intrusion from the wafer transfer opening in-line. Was.

SUMMARY OF THE INVENTION In view of the above-mentioned problems of the prior art, an object of the present invention is to remove gaseous chemical substances taken into a chamber in an exposure system, thereby preventing fogging of optical members such as mirrors and lenses. It is in.

[0012]

According to the present invention, there is provided an exposure apparatus main body, a chamber in which the exposure apparatus is disposed, and an air conditioner room for air-conditioning the chamber.
An exposure system including a substrate processing apparatus such as a coater or a developer that is arranged adjacent to the exposure apparatus and automates application, exposure, and development of a photosensitive agent on a substrate to be exposed such as a wafer, wherein the exposure apparatus and the substrate processing apparatus A gaseous chemical substance is removed in a path for transferring a substrate to be exposed.

As the gaseous chemical substance removing device, for example, a fan for forcibly exhausting air containing the substance to factory equipment can be used. Also, the gaseous chemicals removed thereby are at least NH ₄ ⁺ or SO ₄
Including ^2- . In order to remove the gaseous chemical substance, for example, air containing the gaseous chemical substance on the path is forcibly exhausted to factory equipment by a fan or the like.

Alternatively, by blowing clean air, which has been cleaned by a chemical filter device or the like, onto the delivery path, entry of the air containing the substance from the coater / developer or the like into the exposure apparatus can be prevented. .

[0015]

In this configuration, the substrate is transferred on the substrate transfer path. At this time, the air that enters the exposure apparatus through the opening is ammonium ion (NH ₄ ⁺ ).
And chemical substances such as sulfate ions (SO ₄ ²⁻ ) are removed.
Therefore, the generation of (NH ₄ ) ₂ SO ₄ is prevented, and the opacity of the optical member of the exposure apparatus main body due to such a gaseous chemical substance is prevented. Therefore, the illuminance deterioration of the exposure light is minimized. As a result, the initial yield of the device is maintained for a long time.

[0016]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows an embodiment in which the present invention is applied to a stepper which is one of semiconductor exposure apparatuses. As shown in the figure, the apparatus includes an exhaust device (es) on the wafer transfer path (wc) for shutting off a wafer transfer path (wc) from the outside air and removing a chemical substance entering from the coater / developer. Other configurations are the same as those of the apparatus in FIG. By forcibly evacuating to the factory equipment by the exhaust device (es), chemical substances such as ammonium ions (NH ₄ ⁺ ) and sulfate ions (SO ₄ ²⁻ ) that enter the semiconductor exposure device during wafer transfer are removed.

In the exhaust method shown in FIG. 1, air is exhausted in one direction perpendicular to the exposure surface of the wafer, but air around the opposite wafer surface without an exhaust device is exhausted by the resistance of the wafer itself. Hateful. On the other hand, a two-way exhaust in which another exhaust device is added is conceivable (FIG. 2). As a result, air around the wafer surface that cannot be completely exhausted by the above-described exhaust method can be exhausted.

As still another method, parallel exhaust can be considered. FIG. 3 is a conceptual plan view of a semiconductor exposure system to which parallel exhaust is applied. The advantage of the parallel exhaust is that the air around the wafer can be exhausted evenly as compared with the vertical exhaust. Further, in the vertical exhaust, two exhaust devices are required to exhaust the air around the wafer evenly. However, since the parallel exhaust has one exhaust device, the size and cost of the device can be reduced. As a result, it leads to space saving of the clean room and reduction of capital investment.

The above-described chemical substance removing apparatus is for sucking air containing the above substance and exhausting the air to factory equipment. Conversely, the apparatus blows clean air cleaned by a chemical filter device or the like to blow the air. A method of preventing the air containing the substance from entering the inside of the exposure apparatus body is also conceivable.

FIG. 4 is a diagram to which the above method is applied. In the figure, a chemical filter device 60 is a chemical substance removing device including a dust removing filter (ULPA filter) uf, a chemical filter based on activated carbon or a chemical filter cf using ion exchange resin, and a blower 17. External air is cleaned by a dust removal filter uf and a chemical filter cf, and is blown to a wafer transfer path wc between the coater / developer and the exposure apparatus main body. As a result, the pressure of the wafer transfer path wc becomes higher than the pressure on the coater / developer side or inside the chamber 1, and the flow of air containing gaseous chemicals from the coater / developer to the chamber is cut off. In addition, the air introduced into the chemical filter device 60 or the air derived from the chemical filter device is air-conditioned as necessary.

In the method shown in FIG. 4, one-way spraying is performed in a direction perpendicular to the exposed surface of the wafer. However, similar to the exhaust device, two-way spraying is performed from the exposed surface of the wafer and the back surface thereof. , And parallel spraying, which sprays in parallel to the wafer exposure surface, can be considered.

As described above, the semiconductor exposure apparatus and the coater
A device for removing gaseous chemicals is provided on the wafer delivery path between developers, so that gaseous chemicals such as ammonium ions (NH ₄ ⁺ ) and sulfate ions (SO ₄ ^2- ) are removed. Thus, it is possible to prevent the air containing them from entering the chamber. This allows
The generation of (NH ₄ ) ₂ SO ₄ , which causes the light source device in contact with the air in the chamber and the optical members in the illumination optical system to become cloudy, can be prevented, and the illuminance deterioration of the exposure light can be minimized. By isolating the wafer transfer path from the outside air and connecting the openings, uniform temperature control of the air-conditioned space became possible. Therefore, the initial yield of the semiconductor exposure apparatus can be maintained for a long time.

[0023]

As described above, since the gaseous chemical substance is removed on the substrate transfer path between the exposure apparatus and the substrate processing apparatus, the ammonium ion (NH ₄ ⁺ ) It is possible to prevent gaseous chemical substances such as sulfate ions (SO ₄ ^2- ) from entering the chamber.
This causes the light source device in contact with the air in the chamber or the optical member in the illumination optical system to become cloudy (NH ₄ ).
The generation of ₂ SO ₄ can be prevented and the illuminance deterioration of the exposure light can be minimized. Further, by isolating the substrate transfer path from the outside air and connecting the openings, it is possible to more uniformly control the temperature of the air-conditioned space. Therefore, it is possible to maintain the initial yield of the exposure apparatus for a long period of time.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of an inline semiconductor exposure system according to an embodiment of the present invention.

FIG. 2 is a configuration diagram of an inline semiconductor exposure system according to another embodiment of the present invention.

FIG. 3 is a configuration diagram of an inline semiconductor exposure system according to still another embodiment of the present invention.

FIG. 4 is a configuration diagram of an inline semiconductor exposure system according to still another embodiment of the present invention.

FIG. 5 is a configuration diagram of an inline semiconductor exposure system according to a conventional example.

[Explanation of symbols]

1: chamber, 2, 2 ′: reticle, 3, 3 ′, 3 ″:
Wafer, 4: light source device, 5: illumination optical system, 6: projection lens, 7: reticle stage, 9: wafer stage, 1
0: air conditioner room, 13: filter box, 14: booth, 17: blower, 40: coater, 50: developer,
60: chemical filter device, 81: reticle microscope,
82: off-axis microscope, cf: chemical filter,
es: exhaust device, g: air filter, oa: outside air inlet, ra: return port, uf: ULPA filter, w
c: Wafer delivery path.

Claims (9)

[Claims] 1. An exposure apparatus comprising: an exposure apparatus main body; a chamber in which the exposure apparatus body is disposed; an air conditioner room for air-conditioning the chamber; and a substrate processing apparatus for applying and developing a photosensitive agent on a substrate to be exposed. In the system, an apparatus for removing gaseous chemical substances contained in the atmosphere of the substrate to be exposed being transported is provided on a transport path of the substrate to be exposed, which connects the substrate processing apparatus and the exposure apparatus body. Exposure system characterized by the above-mentioned. 2. The exposure system according to claim 1, wherein the removal device is a device for forcibly exhausting air containing gaseous chemical substances on the path to factory equipment by a fan. 3. The apparatus according to claim 1, wherein the removing device is a device for preventing air containing a gaseous chemical substance on the path from entering the exposure apparatus main body by blowing clean air onto the path. The exposure system according to claim 1, wherein 4. The gaseous chemical is at least NH ₄ ⁺
_4. The exposure system according to claim 1, wherein the exposure system includes SO ₄ ^2- . 5. An exposure apparatus comprising: an exposure apparatus main body; a chamber in which the exposure apparatus body is disposed; an air conditioner room for air-conditioning the chamber; and a substrate processing apparatus for applying and developing a photosensitive agent on a substrate to be exposed. In the system, when transporting the substrate to be exposed between the substrate processing apparatus and the exposure apparatus body, the gaseous chemical substance contained in the atmosphere of the substrate to be exposed being transported on the transport path of the substrate to be exposed, A method of transporting a substrate, comprising removing the substrate. 6. The substrate transfer method according to claim 5, wherein the removal of the gaseous chemical substance is performed by forcibly exhausting air containing the gaseous chemical substance on the path to a factory facility with a fan. . 7. The removal of the gaseous chemical substance by blowing clean air into the path to prevent the air containing the gaseous chemical substance on the path from entering the exposure apparatus main body. The substrate transport method according to claim 5, wherein the substrate transport method is an apparatus. 8. The gaseous chemical of claim 1 wherein the gaseous chemical is at least NH 3.
₄ ⁺ or substrate transfer method according to any one of claims 5-7, characterized in that those comprising a SO ₄ ^2-. 9. The substrate transfer method according to claim 5, wherein said substrate processing apparatus is arranged outside said chamber.