JPH01181522A - X ray aligner for manufacturing semiconductor element - Google Patents

Abstract

PURPOSE:To enable x-axis table driving force to be small and positioning control to be extremely speedy and highly accurate by providing an air cylinder for compensation for balancing each weight of x-axis and y-axis tables. CONSTITUTION:An air cylinder 5 for compensation and a y-axis table 6 are connected magnetically by permanent magnets 10 and 13. Supporting and working forces matching the weight of weight plus y-axis tables 6, 6 of an x-axis table 2 are operated upward by constantly supplying a compressed air of a certain pressure to an actuation chamber 22. A y-axis table 6 is driven upward or downward by linear motors 9 and 8. Thus, in either upward or downward drive, the same driving force can be used for linear motors 7 and 8 for allowing positioning control to be made highly precisely and at high speed.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an X-ray exposure apparatus for "SOR" in a semiconductor device manufacturing process.

[Conventional technology and its issues]

As is well known, in the semiconductor device manufacturing process, it is necessary to align the relative positions of a mask pattern and a wafer pattern. This is called mask alignment or mask alignment, and after this step, exposure is performed by irradiating ultraviolet rays, electron beams, or X-rays. The device that performs this mask alignment and exposure is called an exposure device.

By the way, in response to the demand for ultra-miniaturization and high density semiconductor devices, patterns with a width of 1 μm or less have appeared. For this reason, X-ray exposure devices with short wavelengths have come into the spotlight for exposure (see Japanese Utility Model Publication No. 56-5307). That is, line width 0.25
X-ray exposure using an SOR as a light source is particularly preferable for ultra-precise exposure on the order of μm, and therefore various proposals have been made regarding X-ray exposure apparatuses. In an exposure apparatus using such an SOR as an X-ray source, in addition to large changes in X-ray brightness,
Since the lights are almost parallel, the penumbra blur and runout errors that were problems with conventional xtas (electron beam excited shadow sources and plasma And since the light comes out horizontally,
New constraints have arisen, such as the wafer table (or stage) surface being vertical.

In other words, in an exposure apparatus that uses SOR as an X-ray source,
An X-axis table and a y-axis table are provided to perform positioning in the horizontal (X-axis) and vertical (y-axis) directions with high precision and at high speed. When positioning a table, depending on whether the table is moving upward or downward, the weight of the table itself acts on the actuator that drives it in a positive or negative direction, so positioning control is affected. This causes a large disturbance, making it difficult to position these tables with high precision.

Therefore, conventionally, in this type of normal exposure apparatus, a load equivalent to the weight of the table itself is applied in a direction opposite to the table's own weight in order to avoid the above-mentioned disturbance factors as much as possible.

That is, a device called a counterweight system is known, and this system is configured as follows. A pair of endless steel belts (or wires) are wound around pulleys located above and below, respectively, and a y-axis table is attached across the pair of steel belts.

On the other hand, weights having the same weight as the X-axis and y-axis tables are suspended from steel belts at positions symmetrical to the y-axis tables around these pulleys.

However, in such a counterweight method, l)
There is a problem in that the weight to be controlled is more than twice the table weight, such as the table weight, the weight of the counterweight, and the weight of the steel belt, resulting in an increase in the capacity of the actuator.

2) Also, the steel belt that connects the table and weights is required to have as high rigidity as possible, but on the other hand, it is required to have low bending resistance because it needs to be bent by the pulleys at the top and bottom positions. , both demands conflict with each other. Therefore, there is a problem that the steel belt has low rigidity and also has resistance to bending deformation. Furthermore, the steel bell I has a certain degree of rigidity in the tensile direction, but extremely low rigidity in the compressive direction.Therefore, the table and counterweight form a system with low natural vibration. , there is a problem in that minute vibrations that are inconvenient to alignment are generated. 3) Furthermore, there is a problem in that load fluctuations occur due to frictional resistance of the rotating support portion of the pulley, vibration of the steel belt, and bending resistance of the steel belt.

Therefore, for reasons 1), 2), and 3), this counterweight method is undesirable for high-accuracy and high-speed positioning.

[Means to solve the problem]

Therefore, the present invention was created with a focus on solving such problems, and its gist is that SOR
In an X-ray exposure apparatus that is separated from an X-ray light source, and in which a vertical type X-axis table is installed on a vertical type y-axis table so as to be movable in the horizontal direction, the y-axis table is moved in the vertical direction for positioning. a compensating air cylinder for balancing the weights of the X-axis table and the y-axis table; and a compensating air cylinder provided on the piston of the compensating air cylinder and the y-axis table, respectively; An X-ray exposure apparatus for manufacturing semiconductor devices includes a magnet for connecting a y-axis table in a non-contact manner.

〔Example〕

DESCRIPTION OF THE PREFERRED EMBODIMENTS The structure and operation of the present invention will be explained in detail with reference to embodiments shown in the accompanying drawings. FIG. 1 is a front view of an embodiment of the present invention;
Fig. 2 is a sectional view taken along arrow A in Fig. 1, Fig. 3 is a partially detailed sectional view of Fig. 1, Fig. 4 is a sectional view taken along arrow B in Fig. 3, and Fig. 5 is another embodiment. This is a partial detailed sectional view of FIG. 3. 6th
The figure shows a sectional view taken along arrow C in FIG. 5, and FIG. 7 shows a sectional view taken along arrow D in FIG.

Therefore, this embodiment is an exposure apparatus using an SOR as an X-ray source, which is applied to the manufacturing process of micron-level semiconductor devices such as VLSIs, in which 2 is an X-axis guide, 2 is an X-axis table, and 3
is a y-axis guide with a rectangular cross section, 4 is a support for the y-axis guide,
5 is a compensation air cylinder, 6 is a y-axis table, 7 is a near motor attached to the bottom surface of the y-axis table 6, and 8 is a near motor attached to the top surface of the base 15; these near motors 7 and 8 are attached to the y-axis table. 6 actuator. 9 indicates a static air layer formed between the X-axis guide 3 and the Y-axis table 6 by supplying compressed air from an appropriate pressure air port.

The compensation air cylinder 5 is constructed as follows. That is, 10 is the permanent magnet on the y-axis table side, 1
1 is an air gap formed between the cylinder tube 12 and the permanent magnet 10, 13 is a permanent magnet on the side of the piston 14, and 16 is a plurality of injection holes bored toward the outer circumference at both the upper and lower ends of the piston 14. and communicates with the pressurized air supply pipe 20.

Reference numeral 17 denotes an exhaust port which communicates the working chamber 22 in the upper part of the piston 14 with the atmosphere. 18 is a pressure air supply port that supplies compressed air to the working chamber 22, 19 is a static pressure air layer, and 21 is a yoke.

Since this embodiment has the above configuration, its operation is performed as follows. That is, the X-axis table 2 is
(2) Positioning is performed between the pair of y-axis tables and pulls 6 by driving in the horizontal (X-axis) direction by a near motor (not shown) built into the X-axis guide 1 or by a near motor (not shown).

Also, the pair of y-axis tables 6.6 are
Linear motors 7 and 8 provided on the lower surface of the base 15 and the upper surface of the base 15 drive the base 15 in the vertical (y-axis) direction to perform positioning.

Here, only one side of the pair of y-axis tables 6 will be described below, but compressed air is supplied from the pressure air supply pipe 20 through the jet hole 16 into the gap between the inner surface of the cylinder tube 12 and the outer periphery of the piston 14. is supplied with static pressure air N
19 and at the same time, it also performs a sealing action for the compressed air supplied to the working chamber 22. Therefore, the piston 14
This greatly reduces the sliding resistance and sealing resistance, contributing to the balance accuracy described below.

Piston I4 and y-axis table 6 are permanent magnets 10.13
The supporting and operating force corresponding to the weight of the X-axis table 2 plus the weight of the Y-axis table 6.6 is applied upward by constantly supplying compressed air at a constant pressure to the working chamber 22. If the y-axis table 6 is driven upward or downward by the linear motor 9.8, the same driving force is required for the linear motor 7.8 regardless of whether it is driven up or down, and positioning control can be performed with high precision and Done fast.

In this embodiment, a static load of 1 is applied to the pair of pistons 14.
/2 force respectively, the static load distributed to each piston 14 in the pair of cylinder tubes 12 changes depending on the position of the X-axis table 2 on the X-axis. The position of the table 2 is detected and the working chamber 2 of each cylinder tube 12 is adjusted according to the position.
The pressure of the compressed air in step 2 may be changed, and compressed air in this specification also includes inert gas.

Next, another embodiment of the present invention will be described. In FIGS. 5 to 7, in this embodiment, the X-axis guide 3 of the previous embodiment is omitted, and instead, the outer circumference of the cylinder tube 12 is Compressed air is branched from a pressure air supply pipe 23 and supplied from a plurality of radial directions between the inner circumference of the y-axis table 6 and a static air layer 19 is formed.

〔Effect of the invention〕

The following excellent effects can be expected from the present invention.

In other words, since a compensating air cylinder is provided to balance the respective weights of the X-axis table and the y-axis table, the actuator that drives the y-axis table has a constant driving force and a small capacity, unlike the conventional counterweight method. Therefore, the positioning control of the y-axis table axis can be performed at high speed and with high accuracy without any disturbance factors.

Moreover, since the piston of the compensation air cylinder and the y-axis table are connected non-contactly via a magnet, in other words, it is a rodless cylinder, the connecting member between the piston and the y-axis table is greatly simplified. can.

In addition, although the piston, which is convenient for positioning control, has disadvantages such as vibration, the piston's disturbance factors such as vibration are not transmitted to the y-axis table, creating a vibration-free state and improving positioning accuracy. It will not cause any hindrance.

Furthermore, the problem of reducing the stiffness of a steel belt or the like when acting in a compressive direction, which occurs with conventional counterweight systems, does not occur.

[Brief explanation of the drawing]

Figure 1 is a front view of an embodiment of the present invention, and Figure 2 is A of Figure 1.
3 is a partially detailed sectional view of FIG. 1, FIG. 4 is a partially detailed sectional view of FIG. Corresponds to the figure. 6 is a sectional view taken along arrow C in FIG. 5, and FIG. 7 is a sectional view taken along arrow D in FIG. 2...X-axis table, 5...Compensation air cylinder,
6...y-axis table, 7.8...linear motor, 1
0°13...Magnet. Figure 4 fs7 Figure 14 1

Claims (1)

[Claims] (1) In an X-ray exposure apparatus that is separated from the SOR X-ray light source and in which a vertical type x-axis table is installed on a vertical type y-axis table so as to be movable in the horizontal direction, the y-axis table is moved in the vertical direction. an actuator for positioning the x-axis table and the y-axis table; a compensating air cylinder for balancing the weights of the x-axis table and the y-axis table; An X-ray exposure apparatus for manufacturing semiconductor devices, comprising: a magnet for connecting an air cylinder and the y-axis table in a non-contact manner.