JP2003077867A - Moving stage for imprint lithography - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable uniform pressing of a mold against the surface of a specimen when a slant adjustment mechanism is attached on the sample side and the sample is moved by using a moving mechanism. SOLUTION: A strut 11 is fixed at an almost center of a surface plate 8 having a flat surface, and a pivot 12 is fixed on an upper end surface of the strut 11, as the slant adjustment mechanism. A moving stage 6 is fixed on the moving mechanism 10 which moves on the plane of the surface plate, a sample-holding member 5 is retained by the moving stage 6 via elastic members 7, and a silicon substrate 3 which has a resist 4 on the surface is held by the sample-holding member 5. The mold 2 is arranged directly above the pivot 12 so as to be movable vertically, and the moving mechanism 10 is moved in such a manner that the surface of the resist to which the mold 2 is to be transferred is positioned directly below the mold 2. When the mold is pressed against the resist at a prescribed position, the elastic members 7 are transformed so that the mold and silicon substrate 3 become in parallel with each other in the case that both of them are slanted relatively. As a result, a uniform pressing force can be applied to the resist.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a moving stage of an imprint lithography apparatus that moves a stage that supports a sample in order to press a mold having a predetermined pattern against a resist on the surface of the sample.
Particularly, the present invention relates to a moving stage of an imprint lithography apparatus capable of uniformly pressing the entire surface even when the sample and the mold are relatively inclined.

[0002]

2. Description of the Related Art In recent years, downsizing of ultra-LSI devices represented by high-density memory and system LSI has progressed, and a technique capable of further miniaturization has been required. Therefore, in the semiconductor manufacturing process, lithography is required. The importance of (transfer) technology is increasing. Among them, imprint lithography is a technique of pressing a mold on which a predetermined circuit pattern is formed against a sample substrate whose surface is coated with a resist to transfer the pattern, and various methods have been proposed. This is done as shown in FIG.

In FIG. 3, first, as shown in FIG. 3A, a reverse pattern corresponding to a mirror image of the pattern to be transferred is formed on the surface of the molding material 30 by electron beam lithography or the like, so that a predetermined surface is formed. Uneven shape 3
A mold 32 having 1 is created. On the other hand, FIG.
As shown in FIG. 3, a resist material such as PMMA is applied and cured on the silicon substrate 33 on which the pattern is to be formed to form the resist layer 34.

Next, the entire silicon substrate 33 provided with the resist layer 34 is heated to about 200 ° C. to form the resist layer 3
Soften 4 slightly. In this state, as shown in FIG. 6C, the uneven shape 31 of the mold 32 is arranged at a predetermined position of the resist layer 34, and the uneven shape 31 is formed.
Press against 4. At this time, since the resist layer 34 is softened, the resist layer 34 enters the concave portions of the uneven shape 31, and the resist layer 34 has substantially the same shape as the uneven shape 31. In this state, the entire temperature is lowered to about 105 ° C. to cure the resist layer 34, and then the mold 32 is removed. In this way, the resist layer 34
A concave-convex pattern having a predetermined shape is formed on the.

In the imprint lithography method, in addition to the above, for example, a mold is made of a transparent material such as a quartz substrate, and a liquid photocurable resin is applied on the substrate to be transferred, Press the unevenness of the mold on it, inject the liquid photocurable resin into the unevenness, and in this state irradiate ultraviolet rays from the back side of the transparent mold to cure the resin, and then remove the mold A method of forming a concavo-convex pattern has also been proposed.

In the imprint lithography method as described above, it is necessary to make uniform the pressure distribution in the pressing surface when the mold is pressed against the sample substrate. In order to make the in-plane pressure distribution uniform, it is necessary to increase the parallelism between the mold and the sample substrate, and when the two are not parallel, the mutual inclination must be adjusted on the mold side or the sample side.

In order to make the in-plane pressure distribution uniform when the mold is pressed against the sample substrate as described above, conventionally, an inclination adjusting mechanism having an elastic body or a fulcrum and changing the inclination around the fulcrum is used. Is being used.
4 and 5 show the case where the tilt adjusting mechanism is used on the mold side.
Is shown in the schematic diagram. In FIG. 4, the silicon substrate 37 coated with the resist 36 is placed on the sample table 35, and the mold 38 is pressed against the resist 36 on the silicon substrate 37 by the pressing mechanism 40. FIG. 4 shows a case where the pivot structure 41 is used as the tilt adjusting mechanism. For example, when the sample table 35 is tilted relative to the pressing mechanism 40, the pressing mechanism 40 causes the mold 38 to resist the mold 36. When pressed against, the pivot structure 41 absorbs this inclination, and the mold 38 is pressed against the resist 36 with a uniform force. FIG. 5 uses an elastic body 42 as the inclination adjusting mechanism of FIG. 4, and the elastic body 42 can absorb the inclination. As with the one shown in FIG. It is pressed with equal force.

In the above example, the tilt adjusting mechanism is used on the pressurizing side. However, the same effect can be obtained by using the tilt adjusting mechanism on the sample side, as shown in FIG. 6 (a). ,
It is shown in the schematic diagrams of (b) and (c). FIG. 3A shows an example in which the sample table 35 is supported by the pivot structure 43,
(B) shows an elastic body 44 on the bottom surface of the sample table 35, and (c)
Shows an example in which an elastic body 44 is provided between the sample table 35 and the silicon substrate 37. In each of these methods, the tilt adjusting mechanism functions as expected when the sample is not moved.

[0009]

As described above, in order to press the mold against the resist with a uniform force, an inclination adjusting mechanism including a pivot and an elastic body is provided on the pressurizing side and the pressurizing side. In the case of pressing the mold against a wide surface of the resist at a plurality of points, the inclination adjusting mechanism acts on the entire surface when the inclination adjusting mechanism is provided on the pressure side as shown in FIGS. 4 and 5. However, when the tilt adjusting mechanism is provided on the side where pressure is applied as shown in FIG. 6, it cannot function on the entire surface.

7 (a), (b) and (c) schematically show the problem in the case where the tilt adjusting mechanism is added to the pressure side as described above. What is shown in the figure is an example in which a sample moving stage 45 is added to the ones shown in FIGS. 6A, 6B, and 6C. In the figure, the mold is tilted for easy understanding of the problem, but the same holds true when the moving stage side is tilted. Figure 7
In the example shown in (a), when the mold 38 is pressed against the resist 36, only the A side of the mold 38 is pressed and B
The side cannot be pushed in and tilt adjustment does not work at all. The example shown in FIG. 3B is also the same. Furthermore, FIG.
In the example shown in (c), if the substrate 37 is deformed, it is considered that the inclination adjustment will function to some extent, but the substrate 37 may be damaged by the stress in the A portion. As described above, in imprint lithography involving sample movement, it is a problem to realize a tilt adjusting mechanism on the side of a sample to be pressed when the tilt adjusting mechanism cannot be added to the mold side.

Therefore, according to the present invention, when the mold on which the predetermined pattern is formed is pressed against the resist on the sample surface at a plurality of positions, when the resist side for pressing the mold is moved to a predetermined position, the side for pressing the mold is relatively moved. An object of the present invention is to provide a moving stage for imprint lithography in which even if an inclination adjusting mechanism is provided, the mold can be pressed against the resist with a uniform pressure at all positions.

[0012]

In order to solve the above-mentioned problems, the invention according to claim 1 provides an inclination adjusting mechanism fixed to a support on a surface plate, a movable stage movably provided on the surface plate, A sample supported on the moving stage via an elastic member, and a mold that is arranged so as to face the upper part of the tilt adjusting mechanism and is movable up and down, and presses the resist on the sample surface. It is a moving stage for imprint lithography.

The invention according to claim 2 is characterized in that the tilt adjusting mechanism is a pivot mechanism.
This is a moving stage for imprint lithography.

The invention according to claim 3 provides the movable stage for imprint lithography according to claim 1, wherein the tilt adjusting mechanism is an elastic member.

[0015]

1 (a) and 1 (b) are schematic views showing the basic structure of a moving stage for imprint lithography of the present invention, and FIG. 1 (a) shows a state in which a sample is moved. FIG. 1B shows a case where the mold 2 on the mold holder 1 is pressed against the resist 4 on the silicon substrate 3. The sample holding member 5 that holds the peripheral portion on the silicon substrate 3 is supported between the lower surface of the sample holding member 5 and the upper surface of the moving stage 6 via an elastic member 7 having an extremely small spring constant. The moving stage 6 is fixed on a moving mechanism 10 which can move freely on the surface plate 8, so that when the moving stage 6 moves on the surface plate 8 in a plane, the silicon substrate 3 supported by the moving stage 6 is moved. Also moves together.

A pillar 11 extending to the back surface of the silicon substrate 3 is fixed at a substantially central position of the surface plate 8, and a pivot mechanism 12 as an inclination adjusting mechanism is provided on an upper end surface of the pillar 11. The pivot mechanism 12 is a pivot 1 that constitutes a fulcrum.
3 and a pivot receiver 14 which is swingably supported by the pivot 13 and receives the back surface of the sample substrate 8 at its upper end surface.
It consists of and.

The pivot mechanism as an example of the tilt adjusting mechanism is shown enlarged in FIG. In this pivot mechanism, a pivot 13 having a conical projection 15 and forming the fulcrum, and a pivot receiver 14 having a conical recess 16 are provided, and the center of the conical recess 16 of the pivot receiver 14 is formed. The tip of the conical protrusion 15 of the pivot 13 comes into contact with each other, and both can be relatively tilted about this point.

With such a structure, in the state shown in FIG. 1A, the periphery of the silicon substrate 3 is supported by the elastic member 7, and the back surface of the silicon substrate 3 is compressed by the swing member 14 of the pivot 12. It is supported or is supported by the elastic member 7 with a slight gap. As a result, when the moving mechanism 10 moves on the surface plate 8, the moving member 14 of the pivot 12 is lightly contacted with the back surface of the silicon substrate 3 or is kept in a non-contact state.

When the mold 2 is pressed against the resist 4 on the silicon substrate 3, for example, when the mold 2 is inclined as shown in the figure, both are adjusted according to the inclination of the mold 2 as shown in FIG. The elastic member 7 is compressed and the silicon substrate 3 is tilted so that they are parallel to each other. The above inclination is relative to the mold 2 and the silicon substrate 3. Even if the mold 2 side is horizontal and the silicon substrate 3 side is inclined, the same operation is performed, and both are inclined with respect to the horizontal plane. Is also the same.

When the mold 2 pressurizes the resist 4,
When the center of the pressing force applied to the mold 2 is substantially coincident with the tip of the pivot 12, the pressing force hardly acts on the elastic member 7 supporting the silicon substrate 3, and the mold 2 and the silicon are Imprinting is performed in a state where the inclinations of the substrate 3 match.

After performing the above-mentioned imprint at a predetermined position of the resist 4, when performing the imprint on another portion on the surface of the resist 4, the position of the next imprint by the movement of the moving mechanism 10. Is moved to directly below the mold 2, and the same operation is performed thereafter.

In the above embodiment, the pivot is used as the tilt adjusting mechanism on the column 11. However, the same effect can be obtained by using an elastic member as shown in FIG. 5, for example. Alternatively, the elastic body and the pivot structure may be used in combination.

[0023]

As described above, the moving stage for imprint lithography of the present invention can effectively perform the tilt adjusting function even when the sample is moved while incorporating the tilt adjusting mechanism on the sample side. The present invention is particularly effective when it is difficult to add a tilt adjusting function to the mold side.

[Brief description of drawings]

FIG. 1 is a schematic diagram of the present invention, in which (a) shows a state in which a mold is separated from a resist and a sample is moved, and (b) shows a state in which a mold on a mold holder is pressed against a resist on a silicon substrate. Shows.

FIG. 2 is a diagram showing a pivot mechanism as a tilt adjusting mechanism.

FIG. 3 is a diagram showing a pattern transfer method by imprint lithography.

FIG. 4 is a schematic view of an imprint lithography apparatus provided with a tilt adjusting mechanism having a pivot structure on the mold pressing side.

FIG. 5 is a schematic view of an imprint lithography apparatus provided with a tilt adjusting mechanism made of an elastic member on the mold pressing side.

FIG. 6 is a schematic diagram of an imprint lithography apparatus provided with an inclination adjusting mechanism on the sample side.

FIG. 7 is a schematic diagram of an imprint lithography apparatus in which a tilt adjusting mechanism and a moving mechanism are provided on the sample side.

[Explanation of symbols]

1 Mold holder 2 mold 3 Silicon substrate 4 resist 5 Sample holding member 6 moving stages 7 Elastic member 8 surface plate 10 Moving mechanism 11 props 12 Pivot mechanism 13 pivot 14 Pivot holder 15 protrusions 16 hollows

Claims (3)

[Claims] 1. An inclination adjusting mechanism fixed to a column on a surface plate, a moving stage movably provided on the surface plate, a sample supported on the moving stage via an elastic member, and the inclination adjusting mechanism. A movable stage for imprint lithography, which is arranged so as to be vertically movable so as to face the upper part of the mold and which presses the resist on the sample surface. 2. The moving stage for imprint lithography according to claim 1, wherein the tilt adjusting mechanism is a pivot mechanism. 3. The moving stage for imprint lithography according to claim 1, wherein the tilt adjusting mechanism is an elastic member.