JPH0770460B2 - Projection exposure device - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a projection exposure apparatus for printing a circuit pattern on a mask on a substrate, and particularly to a laser light source and an exposure apparatus for a projection exposure apparatus using laser light as exposure light. The present invention relates to improvement of an optical connection portion with a main body.

[Prior Art] In recent years, an exposure apparatus using a laser as an exposure light source has been receiving attention.

In an exposure apparatus that uses laser light, the light source that oscillates the laser is very large, the cooling fan and other vibrations occur in the laser power supply section, and the light source vibrates during laser oscillation. Therefore, in most cases, the exposure apparatus main body and the laser light source are separately installed. Further, in order to prevent the vibration at the time of laser oscillation from being transmitted to the exposure apparatus main body through the floor surface, there is also one in which the exposure apparatus main body is installed on a vibration isolation table to cope with this vibration.

However, in an exposure apparatus that uses such a laser as an exposure light source, if the laser light leaks from the optical connection part between the laser light source and the exposure apparatus main body, there is a risk that the peripheral devices and the like will be adversely affected. Therefore, further improvement in safety is demanded.

As one of the methods, it is possible to use an optical fiber. However, in the case of the exposure apparatus main body that uses laser light for exposure, the diameter of the laser light incident on the exposure apparatus side is relatively large, so that an extremely thick optical fiber must be used. In addition, since both ends of the optical fiber are fixed to the exposure device side and the laser light source side, respectively, there remains a problem in terms of vibration elimination.

Furthermore, since it is necessary to consider the loss of the laser light due to the optical fiber, it can be said that it is inappropriate to use the optical fiber as a system for supplying the laser light to this type of exposure apparatus.

On the other hand, a conceivable method is to surround the optical path of the optical connection between the laser light source and the exposure apparatus main body with a light shielding member to prevent the laser light from leaking from the connection.

[Problems to be Solved by the Invention] However, in the apparatus in which the laser light source and the exposure apparatus main body are separately installed as described above, when the method of surrounding the optical connection portion with the light shielding member is adopted, The vibration generated in the laser light source is transmitted to the exposure apparatus main body through the light shielding member provided in the optical connection portion, and as a result, the accuracy of various processes such as projection in the exposure apparatus is reduced.

The present invention has been made in view of the above points, and obtains a projection exposure apparatus capable of eliminating adverse effects of laser light on peripheral devices and improving safety, and capable of favorably eliminating vibrations associated with laser oscillation and the like. That is the purpose.

[Means for Solving Problems] A technical point of the projection exposure apparatus according to the present invention is to provide a vibration isolation unit around the optical path of the optical connection between the laser light source and the exposure apparatus main body. It is a thing.

[Operation] In the present invention, since the antivibration light-shielding means is provided around the optical path of the optical connection portion between the laser light source and the exposure apparatus main body, the laser light can be completely shielded and generated by the laser light source. This vibration can be absorbed and blocked by the anti-vibration shading means, and the problem that the vibration is transmitted to the exposure apparatus main body does not occur.

Embodiments Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is an embodiment of the present invention and shows the overall configuration.

In the figure, 10 is a base installed on the floor, and a laser light source 12 is placed on the base 10.

The laser light LA radiated and output from the laser light source 12 is reflected by the mirror.
Reflected at 14, fly-eye lens (fly-eye lens)
It is designed to be incident on 16 to eliminate uneven illumination.

The light that has passed through the fly-eye lens 16 is
It is configured to pass through the optical connection portion 22 between the main body 20 of the exposure apparatus and the main body 20 of the exposure apparatus.

The optical connecting portion 22 shields the laser leaking from the optical connecting portion 22, absorbs the vibration generated in the laser oscillator 18, particularly the laser light source 12, and exposes the vibration through a laser light shielding member (not shown). It is structured so as not to be transmitted to the device body 20 side. The structure of the optical connecting portion 22 will be described later. The optical path in the vicinity of the optical connection portion 22 is surrounded by a light shielding member (not shown).

Next, the light passing through the optical connection portion 22 is transmitted through the lens 24 and the lens 26, is reflected by the mirror 28, and is incident on the main condenser lens 30.

The light transmitted through the main condenser lens 30 is adjusted so that the illuminance is constant, and illuminates the reticle 32. Further, the light transmitted through the reticle 32 is projected by the projection lens 34.
The circuit pattern on the reticle 32 is projected onto the wafer 36 via the.

The wafer 36 is chucked by the vacuum chuck (not shown) on the XY stage 40 placed on the vibration isolation table 38. In addition, all the devices in the exposure apparatus main body section 20 are
It is supposed to be installed on top of.

Next, the structure of the optical connecting portion 22, which is a feature of this embodiment, will be described with reference to FIGS. 2 and 3.

FIG. 2 shows a first mode of the optical connection portion 22.

In the figure, reference numeral 50 denotes (a cross section of) a light shielding member for the laser optical path, which is not shown in FIG. A bellows-shaped bellows connecting portion 52 is integrally formed with the light shielding member 50 so as to be absorbed. The bellows connecting portion 52 is formed of a material that has a hardness that can absorb even subtle vibrations and that can completely shield the laser.

In addition, the light blocking member 50 on the right side is on the laser oscillator 18 side, and the light blocking member 50 on the left side is on the exposure apparatus main body 20 side.

In FIG. 2, (A) shows the reference position before laser oscillation, and (B) shows the reference position when it is deviated from the reference position due to vibration accompanying laser oscillation or the like.

Next, the operation and action of the embodiment according to the first aspect will be described with reference to FIGS. 1 and 2.

The laser light emitted and output from the laser light source 12 is reflected by the mirror 14
The light is reflected by the laser beam, passes through the fly-eye lens 16, and enters the optical connection portion 22 between the laser oscillator 18 and the exposure apparatus main body 20.

The vibration generated in the laser light source 12 due to the laser oscillation is transmitted to the optical connecting portion 22 together with the laser light.

At this time, the state of the optical connecting portion 22 before the laser oscillation is the second
Although the reference state as shown in FIG. 2A, when the vibration is transmitted to the optical connection portion 22 as described above, as shown in FIG. The member 50 will be displaced.

In such a case, as shown in FIG.
The vibration is absorbed by and prevents the left light shielding member 50 from being displaced, and further prevents the vibration from being transmitted to the exposure apparatus main body 20 side.

Next, the light that has passed through the optical connection portion 22 illuminates the reticle 32 by each action of each optical element of the lens 24, the lens 26, the mirror 28, and the main condenser lens 30. Further, the circuit pattern on the reticle 32 is projected and exposed onto the wafer 36 via the projection lens 34.

Thus, since the bellows connecting portion 52 is used for the optical connecting portion 22, it is possible to prevent the vibration from being transmitted to the exposure apparatus main body portion 20 side (left side).

FIG. 3 shows a second mode of the optical connection portion 22.

In the figure, an optical connection portion 22 between the laser oscillation unit 18 and the exposure apparatus main body unit 20 includes a cylindrical first light shielding member 54 and a cylindrical second light shielding member 56 having a diameter smaller than that of the first light shielding member. The first light-shielding member 54 and the second light-shielding member 56 are separated from each other and are formed in a double cylinder shape with a predetermined spatial margin.

The spatial margin between the first light shielding member and the second light shielding member is set to such an extent that the both light shielding members do not come into contact with each other due to vibration, based on the displacement of vibration due to laser oscillation or the like.

Similar to FIG. 2, (A) shows the reference position before laser oscillation, and (B) shows the reference position displaced from the reference position due to vibration associated with laser oscillation and the like.

Next, the operation and action of the embodiment according to the second embodiment will be described with reference to FIG.

Similarly to the above-described first embodiment, when the laser light source 12 radiates and outputs the laser light, the laser light is incident on the optical connection portion 22 and the vibration generated in the laser light source 12 is transmitted.

At this time, the state of the optical connecting portion 22 before the laser oscillation is the third
Although the reference state as shown in FIG. 3A, when the vibration is transmitted to the optical connection portion 22 as described above, as shown in FIG. The member 54 will be displaced.

In such a case, the first light blocking member 54 on the laser oscillator 18 side
Since the second light blocking member 56 on the exposure apparatus main body side is installed with a spatial margin in the separated state as described above, the first light blocking member 54 is displaced as shown in (B). However, there is no contact with the second light shielding member 56, and it is possible to completely prevent the vibration from being transmitted to the exposure apparatus main body 20 side.

Next, the light that has passed through the optical connection portion 22 is subjected to projection exposure by the same configuration and similar action as those in the first embodiment.

As described above, the optical connecting portion 22 is connected to the first light shielding member 54 by the second
Since the light-shielding member 56 and the light-shielding member 56 are formed separately, it is possible to prevent the vibration from being transmitted to the exposure apparatus main body 20 (left side).

The present invention is not limited to the above embodiment,
The optical connecting portion 22 is not limited to the position shown in FIG. 1, and is the same as long as it is a connecting portion between the portion supported by the vibration-proof table 38 and the portion on the other laser light source 12 side. It is possible to obtain various effects.

Further, it can be sufficiently applied to other devices which cause inconvenience due to transmission of vibration.

[Effects of the Invention] As described above, according to the present invention, since the vibration-proof and light-shielding means is provided around the optical path of the optical connection portion between the laser light source and the exposure apparatus main body, it is possible to protect peripheral equipment by laser light. It is possible to remove adverse effects and improve safety, and to perform precise projection exposure without transmitting the vibration generated by the laser light source to the exposure apparatus main body.

[Brief description of drawings]

FIG. 1 is a block diagram showing an embodiment of the present invention, and FIGS. 2 and 3 are sectional views showing an embodiment of the present invention. [Explanation of symbols for main parts] LA ... laser beam, 12 ... laser light source, 18 ... laser oscillator, 20 ... exposure apparatus main body, 22 ... optical connection,
38 …… Anti-vibration table,

Claims (4)

[Claims] 1. A projection exposure apparatus in which a laser device is used as an exposure light source and the laser device and the exposure device main body are separately installed, and a laser beam is provided around an optical path of an optical connection portion between the laser device and the exposure main body. A projection exposure apparatus, which is provided with a shake blocking means. 2. The projection exposure apparatus according to claim 1, wherein the anti-vibration / light-shielding means has a bellows shape. 3. The vibration-proof and light-shielding means is formed in a double cylindrical shape in a state where two light-shielding members are separated with a predetermined spatial margin.
The projection exposure apparatus according to item. 4. The exposure apparatus main body comprises: a projection optical system for projecting a circuit pattern on a reticle onto a wafer; and an illumination optical system including a condenser lens for illuminating the reticle with laser light from the laser apparatus. A fly-eye lens system that emits laser light from the laser device toward an illumination optical system in the exposure apparatus body is provided on the laser device side. The projection exposure apparatus according to claim 1.