JPH0240594A - Flap stage - Google Patents

Abstract

PURPOSE:To facilitate the control of a stage and to obtain a flap displacement of high resolution and high precision by providing three four-joint links formed integrally for supporting a plate. CONSTITUTION:When a voltage is applied to a piezoelectric element 8, a straight advancing displacement S thereby generated generates a displacement (t) in an output part 10 by a minute displacement link mechanism which is constructed of links of hinges 2 to 5, intermediate parts 9 and 11 and the output part 10 with a base 1 used as a fixed link. Moreover, the displacement (t) is transmitted as a flap displacement to a flap plate 13 through the intermediary of a columnar hinge 12. When a distance between the hinge 2 and the hinge 5 is set to be (m) and a distance between the hinge 4 and the hinge 5 to be l in the link mechanism, the displacement (t) in the output part 10 is t=(l/m)S.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention is a thin, high-resolution,
Regarding a highly rigid tilting stage.

[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 can handle masks and wafers with a thickness of 10 μm to 5 μm.
It is a method that transfers fine patterns of 0.5 μm or less by holding them parallel to each other through a minute gap of 0 μm and using alignment marks to perform fine alignment of 0.1 μm or less, and has recently received particular attention. There is. The mask stage that holds the X-ray mask and the wafer stage that holds the wafer require a thin, high-resolution, and highly rigid tilting stage 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 includes a hollow cylindrical stage base 114, a hollow disc spring 115 whose outer periphery is fixed to the inside of the stage base 114, and a mask chuck mounting frame 113 fixed to the inner periphery of the hollow disc spring 115. and the mask chuck 102 held by the mask chuck mounting frame 113.
, armatures 109 to 112 arranged equiangularly on the upper surface of the mask chuck mounting frame 113, and armatures 109 to 112.
Electromagnets 105 to 108 are mounted on the stage base 114 and facing the stage base 114.

When a positive current flows through the electromagnet 105 and a negative current flows through the electromagnet 107, an attractive force is generated between the electromagnet 105 and the armature 109, and a repulsive force is generated between the electromagnet 107 and the armature 111, which balances the restraining force of the hollow disc spring. posture, that is, amateur 11
The mask chuck mounting frame 113 to which 1 is attached is indicated by arrow F.
It is tilted and displaced in the direction.

Further, by passing currents of the same magnitude through the electromagnets 105 to 108, they can be displaced in the Z direction. Therefore, the mask chuck 10 is attached to the mask chuck mounting frame 113.
The mask 11 held through the wafer 2 can be positioned parallel to the wafer 12 and at a predetermined gap amount.

[Problem to be solved by the invention]

When the conventional tilting stage described above applies tilting displacement and Z direction displacement to the mask 11, the hollow disk spring 11
5. Since the outer and inner circumferences of the wafer 12 and the mask are fixed to the stage base 114 and the mask chuck mounting frame 113, the wafer 12 and the mask must undergo complicated deformation and control the current flowing through the electromagnets 105 to 108 in a complicated manner. 11 in parallel takes a lot of time.

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 11 and the wafer 12 on the upper surface of the mask 3 and near the exposure area. Although it must have a thin structure,
Providing 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, there are also methods such as providing a slit in a hollow disc spring or using a columnar elastic member as described in JP-A No. 61-90432. However, since the force generated by the electromagnet is small, the spring constant must be made small, and the rigidity of the entire tilting stage cannot be increased, making it vulnerable to vibration.

[Means to solve the problem]

The tilting stage of the present invention includes three four-bar links having one end fixed to a base plate and having four hinges, first to fourth, and one end fixed to the base plate and the other end of the four-bar link. three piezo elements fixed to the three piezo elements, three cylindrical hinges fixed to the output section sandwiched between the second and third hinges of the three four-bar links;
It is composed of one tilting plate fixed to two cylindrical hinges.

〔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 stage shown in FIG. 1 has a base 1 as a fixed part and a four-bar link 6 having four hinges 2, 3, 4.5,
A piezo element 8 whose both ends are fixed to the fourth hinge 5 and the base 1, a cylindrical hinge 12 fixed to the output part 10 sandwiched between the second hinge 3 and the third hinge 4, and a cylindrical hinge 12 It is configured to include a fixed tilting plate 13.

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
Hinge 23.4.5 with base 1 as a fixed link;
A displacement t is generated in the output part 10 by a minute displacement link mechanism constituted by links between the intermediate part 9.11 and the output part 10, and is further transmitted as a tilt displacement to the tilt plate 13 via the cylindrical hinge 12.

In the link mechanism, the distance between hinge 2 and hinge 5 is m,
If the distance between the hinge 4 and the hinge 5 is as follows, the displacement t of the output section 10 is t=(7m)S.

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 backlash.

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 cross-sectional view taken along line XI-x2 in Fig. 2, and Fig. 4 is a view when Fig. 3 is operated. FIG.

The mask stage tilting stage shown in FIGS. 2 and 3 has a link mechanism whose principle is shown in FIG. 1 is integrally formed and has a hollow disk shape.

Each of the four-bar links 6a, 6b, and 6c has four hinges 2.
The three piezo elements 8a, 8b, 8c have one end fixed to the base 1, and the other end fixed to the hinges 5a, 5b, 5c, respectively. Output portions 10a, 10b of three four-bar links 6a, 6b, 6c.

10c are cylindrical hinges 12a and 12b, respectively.

Mask chuck (tilt plate) 13 via 12c
' is supported.

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.

When voltage is applied to the piezo element 8a attached to the four-bar link 6a, a linear displacement S is generated, and this linear displacement S
generates a displacement t at the output portion 10a of the four-bar link 6a, as shown in the principle of FIG. The mask chuck (tilt plate) 13' is angularly connected to the output parts 10a, 10b, 10c by the cylindrical hinges 12a, 12b, 12c, so that the displacement t of one output part 10a causes the other output parts to move. It is possible to obtain independent tilting displacement θ without interference from 10b and 10c, and the mask chuck (
The mask 21 held by the tilting plate 13' can be easily positioned parallel to the wafer.

Furthermore, 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 between the mask 21 and the wafer 22 can be positioned to a predetermined size.

The stroke of piezo elements 8a, 8b, 8c is 15 μm
The stroke required for the tilt stage is 50 μm.
The distance between the hinges is 50/10 = 7.
The dimensions are such that m is satisfied.

Since the piezo element is a laminated type that can be driven at a low voltage of about 100V, it is small and can generate large stress, and the heat generation can be almost ignored, so the link mechanism can be formed as one piece, increasing the rigidity of the stage. .

In addition, since the three four-bar links can be manufactured simultaneously using wire-cut electric discharge machining, the dimensional accuracy of the hinge part can be easily managed and the spring constant can be made uniform, so the motion characteristics of the three four-bar links 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 there is no fastening part and it can be formed with high dimensional accuracy. Therefore, it can be supported with high rigidity without slipping or rattling.

In addition, by providing a rotatable cylindrical hinge between the three four-bar links and the tilting plate, there is no interference change due to displacement of the three four-bar links on the three axes, making it easier to control the tilting stage. .

In addition, by providing a piezo element instead of an electromagnet, it generates less heat and can generate large stress and minute displacement.
High-resolution and highly accurate tilt displacement 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 the drawing]

Fig. 1 is a sectional view showing the principle of an embodiment of the present invention, Fig. 2 is a plan view showing an embodiment of the invention, Fig. 3 is a front sectional view of Fig. 2, and Fig. 4 is a sectional view of the third embodiment of the invention. FIG. 5 is a plan view showing a conventional example, and FIG. 6 is a front sectional view of FIG. 5. 2.3, 4.5... Hinge, 2a, 3a, 4a. 5 a---hinge, 2b, 3b, 4b, 5b...hinge, 2c, 3c, 4c, 5ic---hinge, 6.6
a, 6b, 6cm-・4 section link, 8.8a, 8b, 8
cm piezo element, 12.12a, 12b, 12cm cylindrical hinge, 13... tilting plate, 13'... mask chuck.

Claims (1)

[Claims] three four-bar links having one end fixed to the base plate and having four hinges numbered first to fourth, 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. element, three cylindrical hinges fixed to the output part sandwiched between the second and third hinges of the three four-bar links, and one cylindrical hinge fixed to the three cylindrical hinges.
A tilt stage characterized by comprising a tilt plate and a tilt plate.