JPH0557555B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a tilting stage, and particularly to a tilting stage applicable to a mask stage or a wafer stage of an X-ray exposure apparatus.

[Technological environment]

In recent years, there has been a trend toward higher precision in exposure apparatuses for semiconductor manufacturing. In particular, X-ray exposure equipment holds the mask and wafer parallel to each other with a small gap of 10 μm to 50 μm, and uses alignment marks to perform minute alignment of 0.1 μm or less to transfer fine patterns of 0.5 μm or less. This is something that has received particular attention recently. A mask stage that holds an X-ray mask,
The wafer stage that holds the wafer requires a tilting stage that is thin, has high resolution, and has high rigidity in order to align the mask and wafer in parallel.

[Conventional technology]

As a conventional technique, for example, Japanese Patent Application Laid-Open No. 61-904320
There is a tilt stage shown in the conventional example.
This conventional tilting stage will be explained with reference to the drawings.

FIG. 5 is a plan view showing a mask stage of an X-ray exposure apparatus equipped with a conventional tilting stage, and FIG. 6 is a front sectional view of FIG. 5. The conventional tilting stage shown in the figure has a hollow cylindrical stage base 11.
4, a hollow disc spring 115 whose outer periphery is fixed inside the stage base 114, and a hollow disc spring 11.
Mask chuck mounting frame 11 fixed to the inner circumference of 5
3, the mask chuck 102 held by the mask chuck mounting frame 113, and the mask chuck mounting frame 1
Amachiya 109-1 arranged at equal angles on the top surface of 13
12, and electromagnets 105 to 105 mounted on the stage base 114, facing the armatures 109 to 112.
108.

In the figure, a positive current flows through electromagnet 105 and electromagnet 107
When a negative current is passed through the electromagnet 105 and the armature 1
09 has attractive force, electromagnet 107 and amachia 111
A repulsive force is generated, and the mask chuck mounting frame 113 to which the armature 111 is attached is tilted and displaced in the direction of arrow F in the figure, in a posture balanced with the restraining force of the hollow disc spring. Furthermore, electromagnets 105 to 10
8 can be displaced in the Z direction by passing a current of the same magnitude through them. Therefore, the mask 21 held by the mask chuck mounting frame 113 via the mask chuck 102 can be positioned parallel to the wafer 22 and at a predetermined gap amount.

[Problem that the invention seeks to solve]

In the conventional tilting stage described above, when giving tilting displacement and Z-direction displacement to the mask 21, the outer and inner circumferences of the hollow disc spring 115 are fixed to the stage base 114 and the mask chuck mounting frame 113, respectively, so that complicated deformation is not required. So, electromagnet 105
The current flowing through the wafer 22 and the mask 21 must be controlled in a complicated manner, and it takes a lot of time to align the wafer 22 and the mask 21 in parallel. In addition, in the case of an X-ray exposure apparatus, as described in Japanese Patent Laid-Open No. 60-201344, it is necessary to place a positional deviation detection device between the mask 21 and the wafer 22 on the upper surface of the mask 21 and near the exposure area. Although it must have a thin structure, the provision of an electromagnet has the disadvantage that it is difficult to construct a thin structure. Furthermore, since the force that can be generated by an electromagnet is small, in order to obtain stable tilting displacement, a slit is provided in the hollow disc spring.
There is also a method of using a columnar elastic member as described in , but since the force generated by the electromagnet is small, the spring constant must be small, and the rigidity of the entire tilting stage cannot be increased, so it is weak against vibration. It was hot.

[Means for solving problems]

The tilting plate of the present invention has three four-bar links each having one end fixed to the base plate and having four hinges, and three piezos having one end fixed to the base plate and the other end fixed to the other end of the four-bar link. and one tilting plate fixed via a hinge to the output part sandwiched between the second and third hinges of the three four-bar links.

〔Example〕

Next, embodiments of the present invention will be described in detail with reference to the drawings.

FIG. 1 is a sectional view showing the principle of an embodiment of the present invention.

The tilting plate whose principle is shown in Figure 1 is base 1.
A four-bar link 6 having four hinges 2, 3, 4, and 5 as a fixed part, a fourth hinge 5, and a base 1.
A piezo element 8 having both ends fixed to the output part 10 sandwiched between the second hinge 3 and the third hinge 4.
and a tilting plate 13 fixed via a fifth hinge 12.

Next, the principle of operation will be explained with reference to the drawings.
The linear displacement S that occurs when a voltage is applied to the piezo element 8 is generated by using the base 1 as a fixed link and the hinge 2,
3, 4, 5, intermediate parts 9, 11, and output part 1
The displacement t shown in the figure is generated in the output section 10 by the minute displacement link mechanism composed of 0 links, and further transmitted to the tilting plate 13 via the hinge 12 as a tilting displacement.

In the link mechanism shown in the figure, the distance between hinge 2 and hinge 5 is m, and the distance between hinge 4 and hinge 5 is l.
Then, the displacement t of the output section 10 is t=l/ms.

Furthermore, since the entire link mechanism is formed in one piece, minute displacements of the piezo element 8 can be stably transmitted to the tilting plate 13 without slipping or bumping. FIG. 2 is a plan view showing a mask stage of an X-ray exposure apparatus equipped with a tilting stage according to the present invention, and FIG. 3 is a sectional view taken along X ₁ and X ₂ in FIG.
FIG. 4 is an explanatory diagram of the operation when FIG. 3 is operated.

The mask stage tilting stage shown in FIGS. 2 and 3 has a link mechanism whose principle is shown in FIG. 1
is formed in one piece and has a hollow disk shape. The four-bar links 6a, 6b, and 6c each have four hinges 2a to 5a, 2b to 5b, and 2c to 5c;
The piezo elements 8a, 8b, 8c have one end fixed to the base 1, and the other end fixed to the hinge 5a, 5b, 5.
Each is fixed at c. Output parts 10a, 10b, 10 of three four-bar links 6a, 6b, 6c
c supports a mask chuck (tilt plate) 13 via hinges 12a, 12b, and 12c, respectively.

Next, the operation will be explained in order with reference to the drawings.
FIG. 4 is an explanatory diagram of the operation when the cross-sectional view of FIG. 3 is operated. In the figure, when a voltage is applied to the piezo element 8a attached to the four-bar link 6a, a linear displacement s is generated, and as shown in the principle of FIG.
A displacement t is generated at 0a. The mask chuck (tilt plate) 13' has hinges 12a, 12b,
12c, three output parts 10a, 10b,
10c, the displacement t of one output portion 10a causes the hinges 12a, 1
2b and 12c can each be deformed to obtain a tilting displacement θ, and the mask 21 held by the mask chuck (tilting plate) 13' can be positioned parallel to the wafer.

Further, by applying the same voltage to the piezo elements 8a to 8c, it is possible to similarly obtain displacement only in the Z direction, so that the gap of the wafer 22 of the mask 21 can be positioned to a predetermined size. The strokes of piezo elements 8a, 8b, 8c are
The distance between the hinges is about 15μm, and the stroke required for the tilt stage is about 50μm, so the distance between the hinges is
This is a method that satisfies 50/15=l/m. The piezo element is a laminated type that can be driven at a low voltage of about 100V, so it is small and can generate large stress, and the heat generation can be almost ignored, so the link structure can be formed in one piece, increasing the rigidity of the stage. .

In addition, three four-bar links can be manufactured at the same time using wire cut electric discharge machining, making it easier to control the dimensional accuracy of the hinge part and making the spring constant uniform.
The motion characteristics of each four-bar link can be made uniform.

〔Effect of the invention〕

The tilting stage of the present invention has three integrally formed four-bar links instead of a hollow disk or a columnar elastic spring to support the tilting plate, so it can be formed with high dimensional accuracy without any fastening parts. , can be supported with high rigidity without slipping or rattling.
In addition, by providing a piezo element instead of an electromagnet, it is possible to generate small displacements with small heat generation and large stress, so that tilting displacements with high resolution and high accuracy can be obtained. Furthermore, by arranging the piezo elements radially, a thin structure can be achieved, which has the effect that the mask stage and wafer stage of the X-ray exposure apparatus can be made smaller.

[Brief explanation of drawings]

FIG. 1 is a sectional view showing the principle of an embodiment of the present invention, and FIG. 2 is a plan view showing a mask stage of an X-ray exposure apparatus equipped with a tilting stage according to the present invention.
Fig. 3 is a front cross-sectional view of Fig. 2, Fig. 4 is an explanatory diagram of the operation when Fig. 3 is operated, and Fig. 5 is a plan view showing the mask stage of an X-ray exposure apparatus equipped with a conventional tilting stage. 6 is a front sectional view of FIG. 5. 2-5, 12... Hinge, 2a-5a, 12a
...Hinge, 2b to 5b, 12b...Hinge, 2
c~5c, 12c...hinge, 6, 6a, 6b,
6c...4 section link, 8, 8a, 8b, 8c...
Piezo element, 13... Tilt plate, 13...
Mask check.

Claims (1)

[Claims] 1. Three four-bar links having one end fixed to the base plate and having four hinges, three piezo elements having one end fixed to the base plate and the other end fixed to the other end of the four-bar link, and three piezo elements. A tilting stage comprising: one tilting plate fixed via a hinge to an output portion sandwiched between the second hinge and the third hinge of the four-bar link.