JPS60182444A - Semiconductor exposing device - Google Patents

Abstract

PURPOSE:To remove an error in the rotation of a mask sufficiently by arranging a diaphragm, and controlling supply pressure finely and thus making a fine adjustment in a rotating direction. CONSTITUTION:The device consists of a rotating disk 9, wafer 3, air pressure operating device 17, motor 15 for rotation, feed screw 16, etc. The wafer 3 is positioned in a direction theta in a figure on the plane of a wafer moving stage by the air pressure operating device 17, etc., of a theta driving part. When the supply pressure of the air pressure operating device 17 rises above its initial state, one side of the air pressure operating device 17 projects by diaphragm effect. Consequently, the rotating disk 9 rotates in a clockwise direction CC. When the supply pressure of the air pressure operating device 17 drops below its initial state, said one side moves back and the rotating disk 9 reverses. Thus, an error in the rotation of the photomask 1 is removed sufficiently and the photomask 1 moves together with the wafer 3 in one body to perform slit exposure successively.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an exposure apparatus, and particularly to an exposure apparatus for semiconductor continuous printing which requires high transfer accuracy.

In recent years, in order to achieve finer patterns and higher integration from IC-LSI to VLSI, high-precision, high-quality exposure apparatuses have been required.

One of the important elements required of these devices is the positioning accuracy necessary to accurately position the notches of the photomask in the next process on the pattern on the wafer printed with the photomask in the previous process. This proposal is concerned with obtaining this positioning accuracy with high precision.

<Description of Prior Art> As shown in FIG. 1, a semiconductor printing apparatus uses a mirror imaging optical system to apply a pattern of a photomask (1) onto a sea urchin/\-(3) using slint light (SR). ),
An apparatus is known in which the entire exposure is completed by moving the photomask (1) and the mask (3) as one body in a direction perpendicular to the longitudinal direction of the slint (in the direction of arrow (A)). This apparatus is an optical system in which a photomask image is inverted with respect to the optical axis and projected onto the wafer surface in the longitudinal direction of the slint, the so-called direction perpendicular to arrow (A). Note that (mI, m2) in the figure indicates a part of both sites of the trapezoidal mirror, (m3) indicates a concave mirror, and (m4) indicates a convex mirror, respectively.

In this case, in order to align each of the seven alignment marks on the photomask and the wafer using the alignment optical system, that is, to achieve positional alignment, the photomask and the wafer may be integrally displaced.

Conventionally, it has been known to use a combination of a moving table using rolling or sliding holes and a driving member such as a motor or Schilling to shift the photomask and wafer. There is a stake slip in the moving platform, which makes the movement not smooth, and the drive system suffers from puncture crashes, resulting in poor responsiveness to minute feeds, long positioning times, and poor positioning accuracy and operability. Ta.

As a method to greatly improve these disadvantages, a method has been proposed in which positioning is performed by controlling the supply pressure of the floating plate using a fluid bearing.

However, in this method, positioning in the X and Y directions can be achieved with high precision, but positioning in the e direction is difficult because the rotation center of the fluid bearing is not at the center of the photomask and the wafer. Other components in the x and y directions are generated, which takes a long time for positioning and makes it impossible to obtain high positioning accuracy. Also, normally, compared to the spacing between the alignment marks, the spacing in the moving direction of the two floats required to control the hydrodynamic bearing in the e direction is larger, so when positioning in the e direction, It is necessary to greatly control the gap between the float and the kite, and with an initial gap of about 5 μs to 8 μs, a sufficient amount of e-movement cannot be achieved. For these reasons, it was difficult to realize this.

<Objective of the Invention> The object of the present invention is to achieve accurate positioning in the X, Y, and 0 directions. Therefore, the alignment of the photomask and wafer in the X and Y directions is performed using a hydrodynamic bearing. The direction is determined by driving a zero-rotation plate on the stage by controlling the supply pressure of a pneumatic actuator without hysteresis, a so-called tire flam, to achieve highly accurate positional alignment.

In the embodiments of the present invention, which will be described later, two objects, a photomask and a wafer, are aligned, and two objects, a photomask and a wafer, are aligned using a fluid bearing means.
In an apparatus that sequentially exposes objects by moving them in unison, the X and Y directions are controlled by the supply pressure of a fluid bearing, and the e direction is operated by pneumatic pressure. This semiconductor exposure apparatus is characterized in that it performs exposure by controlling the supply pressure of a so-called tire flam.

<Description of Embodiment> Here, one embodiment of the present invention will be described with reference to the accompanying drawings.

In FIG. 2, (1) is a photomask movement stage for moving the photomask. (3) is a wafer, and (4) is a wafer movement stage for moving the wafer. Photomask moving stage (2)
and the wafer moving stage (4) are connected by a connecting body (5). (6) is an air bearing, and the photomask moving stage (2) is connected by the connecting body (5).
) and a wafer movement stage (4), and is a fully restrained air bearing whose posture can be controlled.

During exposure, the air hair ring moves the photomask (1) and the wafer (3) as one body in the direction perpendicular to the plane of the paper in FIG. 2, and they are sequentially exposed to the sliver 71-Ri light.

Note that (7) is an air hair link, which is a vertical restraint type air hair link that does not affect the posture of the photomask or wafer and only functions as a load container.

Describing the alignment method here, as shown in FIG. 2, first, the photomask and wafer are roughly aligned using the photo mask moving stage (2) and the wafer moving stage (4). In the case of coarse adjustment, the air hair ring system is stationary.

A rough positioning method will be described with reference to FIG. FIG. 3 is a plan view of a wafer moving stage (4) that is moved by a pole. (8) is a moving plate for the X and Y directions, and (9) is a rotating plate for the e direction. (10) is X.

It is a T-shaped bar for moving the Y moving plate (8) in the X direction, and is restrained by a V kite (It) consisting of a groove and a ball. (12) is a T-shaped par (
This is the motor of the X-axis cylinder for moving the lO). (
13) is a bar for moving the X, Y moving plate (8) in the Y direction. (14) is a Y-axis cylinder motor for moving the par (13).

(15) is a motor for zero rotation, and by rotating the feed screw (16), the zero rotation plate (8) is coarsely adjusted. (17) is a pneumatic actuator, so-called tire plum, which is activated during fine adjustment. Note that the photomask moving stage (2) also has the same structure as the wafer moving stage (4).

As mentioned above, after rough alignment on the movement stages (2, 4), the supply pressure of the levitator of the fully restrained air bearing (6) and the pneumatic actuator (17) on the wafer movement stage (4) are adjusted. ) Fine positioning is achieved by controlling the supply pressure.

Next, the air bearing control method will be described in detail.

Figure 4 shows the configuration of a kite with a fully restrained air bearing (6). (24) is a kite rail, and (25) is a sliding member, which moves in the direction of arrow (A). The left and right direction (X direction) of the figure is (1B, +9.20.21) (7) floating L
It is restrained by a bat, and the front and back directions of the figure are restrained by a float (20, 23).

Here, a method for aligning the photomask and wafer in the Y direction will be explained using FIGS. 5 to 7. Figures 5 to 7 are side views of the fully restrained air hair ring (6) kite. Figure 5 shows the sliding member (2
5). Front punt (22), rear puff) (2
3) Since the supply pressures are the same, the distance (d) between the kitrail (24) and the punt (22, 23) is the same. When positioning is performed, the supply pressure of the puff 1-(23) on the No. 1 side is changed. FIG. 6 shows the behavior of the sliding member (25) when the supply pressure of the bat (23) is lowered. By lowering the supply pressure, the distance (d') between the hunts (23) decreases, so that the sliding member (25) undergoes zero rotation about the pan (22).

FIG. 7 shows the behavior of the sliding member (25) when the supply pressure of the bat (23) is increased. When the supply pressure is increased, the distance (d'') between the roses I/(23) increases, so the sliding member (25) rotates θ in the opposite direction to that shown in Fig. 6 with the punt (22) as the rotation center. When the sliding member (25) rotates, the mounted photomask and wafer also rotate by the same amount with respect to the optical system.In a reflective printing device,
When the photomask and wafer are rotated slightly together with respect to the optical system, in Figure 8, if the rotation angle eo is the distance between the photomask (1) and the wafer (3), then the amount of 1tane is Only the photomask and wafer will be misaligned relative to each other. This makes it possible to align the photomask and wafer in the Y direction.

Next, a method for aligning the photomask and wafer in the X direction will be explained using FIG. 9. FIG. 9 is a top view of the guide of the fully restrained air bearing (6).

The solid line shows the behavior of the sliding member (25) in the normal case. Since the supply pressure of the left and right butts (18 to 21) is the same, the puff l-(18, l1l) and guide rail (2
4) The interval (Xo) is constant. When positioning in the X direction is performed from the state shown by the solid line, it is sufficient to change the supply pressure of the punts (18, 19) on one side (or both sides).

The one-point button line shows the behavior of the sliding member (25) when the supply pressure of the puffs (18, 19) is lowered. By lowering the supply pressure, the distance (Xo) between the butt (18, 19) and the kite rail (24) is reduced by a certain amount. This causes the sliding member (25) to shift by an amount in the X direction.

The two-dotted chain line shows the behavior of the sliding member (25) when the oil pressure of the puffs (18, 19) is increased. By increasing the supply pressure, the distance (Xo) between the punt (18, 19) and the kite rail (24) increases by an amount. As a result, the sliding member (25) is displaced by an amount relative to the optical axis in the direction opposite to the solid line kJ in the X direction. When the sliding portion (25) is displaced with respect to the optical axis, the mounted photomask and wafer are also displaced by the same amount. In a reflective printing system, if the photomask or wafer is displaced with respect to the optical axis, 2Xl
, the photomask, and the wafer will be relatively misaligned. This makes it possible to align the photomask and wafer in the X direction.

Next, a method for aligning the photomask and wafer in the e direction will be explained using FIGS. 10 to 12. 1st theta
FIG. 12 is a plan view of the wafer moving stage (4), in which only the θ driving section is extracted. Although not shown, the position of the rotating plate (9) is appropriately measured by a measuring device.

FIG. 10 shows the initial state of the pneumatic actuator (17). This state is always present during rough adjustment. FIG. 11 shows the state when the supply pressure of the pneumatic actuator (17) becomes higher than the initial state. When the supply pressure increases, one side of the pneumatic actuator (17) protrudes due to the diaphragm effect.

As a result, the rotating plate (9) for e rotates counterclockwise (CC). FIG. 12 shows a state when the supply pressure of the pneumatic actuator (17) is lower than the initial state. When the supply pressure becomes low, one side of the pneumatic actuator (17) retracts due to the diaphragm effect. As a result, the rotating plate of e (9
) rotates clockwise (CW).

<Description of Effects> As described above, the present invention uses a pneumatic actuator, so-called diaphragm, to perform fine adjustment in the e direction by controlling the minute supply pressure, thereby reducing the rotation error of the mask. It is possible to sufficiently remove the above-mentioned particles, which greatly contributes to semiconductor printing exposure apparatuses that require high transfer accuracy.

[Brief explanation of drawings]

FIG. 1 is a schematic diagram illustrating the invention in detail, and FIG.
FIG. 3 is a front view of the apparatus using the embodiment of the present invention, FIG. 3 is a plan view of the main parts, FIG.
FIGS. 12 to 12 are schematic diagrams for explaining the operation of the above embodiment. 1: Photomask, 3: U/\-1 6: Air bearing...fluid bearing means, 17: Pneumatic actuator (diaphragm). Figure 4 Y Figure 5 Figure 7 Y□ Figure 9

Claims (1)

[Claims] X
, Y direction is performed by controlling the supply pressure of a fluid bearing, and e direction is performed by controlling the supply pressure of a pneumatic actuator, so-called diaphragm.