JPH07235486A - Manufacture of device - Google Patents

Abstract

PURPOSE:To provide a method of the manufacture of devices which makes it possible to manufacture highly accurate devices by step and scan exposure. CONSTITUTION:An original plate stage 2 supports an original plate 1, and a substrate stage 4 supports a substrate 3 during the step and scan exposure. The original plate stage 2 and the substrate stage 4 are separately shifted by respective driving sources 16, 17 in synchronization with each other. After the completion of each scan exposure, the substrate is shifted step by step relative to the original plate by means of the substrate stage. Thus a plurality of regions on the substrate are exposed one by one.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a device manufacturing method for printing a pattern image, for example, a semiconductor circuit on an original plate on an object to be exposed, and is particularly suitable as a division scan (step and scan) type for dividing and burning a large screen. The present invention relates to a device manufacturing method that can be implemented using a projection exposure apparatus.

[0002]

2. Description of the Related Art Conventionally, in a device manufacturing method using a scan type semiconductor printing apparatus, a mask and a substrate (or a wafer) are placed on a carriage, and the whole screen is exposed by scanning and moving the mask and the substrate onto an exposure surface. is doing.

However, as a recent trend, when the screen becomes large due to the increase in the diameter of the wafer for the purpose of reducing the chip cost and the manufacture of a large liquid crystal display panel for a liquid crystal TV, the exposure range is reduced. There is a problem that the apparatus becomes large in size due to the necessity of increasing the size and lengthening the scan length.

As a countermeasure against this, a step-and-scan burning method has been considered in which the screen is divided and the scan burning is divided into a plurality of times.

FIG. 2 shows the structure of such a step-and-scan type exposure apparatus previously proposed by the present inventors. In the figure, 1 is a photomask on which a printing pattern is formed, 2 is the mask 1 on which X,
The mask stage is movable in the Y and θ directions. 3 is a glass substrate on the surface of which a large number of pixels and switching transistors for controlling the on / off of these pixels are formed in order to manufacture a liquid crystal display plate, and the length of the diagonal line. Is a square of about 14 inches. A substrate stage 4 holds the substrate 3 and is movable in X, Y, and θ directions. Reference numeral 5 is a well-known mirror projection system including a combination of a concave mirror and a convex mirror, which is a mask stage 2
The pattern image of the mask 1 aligned at a predetermined position is projected onto the substrate 3 at the same size. An illumination optical system 6 illuminates the mask 1 at the exposure position with light of a specific wavelength from a light source (not shown), and exposes a photosensitive layer on the substrate 3 through a pattern on the mask to expose the photosensitive layer on the mask. This is for allowing the pattern to be transferred onto the substrate 3. The optical axis of the projection system 5 is made to coincide with the optical axis of the illumination system 6.

Reference numeral 7 denotes a LAB which is movable along two guide rails 8 provided in the Y direction (direction perpendicular to the paper surface).
(Linear air bearing), one of which is an X-direction (horizontal direction of the paper), Z-direction (the vertical direction of the paper) constraint type, and the other is a Z-direction constraint type. Reference numeral 9 denotes a holder (carriage) which holds the mask stage 2 and the substrate stage 4 in a fixed relationship, and integrally supports the mask 1 on the mask stage 2 and the substrate 3 on the substrate stage 4 by being supported by the LAB 7. It is possible.

Reference numeral 11 designates a mask transporting device, which comprises a plurality of masks 1.
Is set, and the mask stage 2 is moved every time the substrate 3 is divided and exposed by moving the desired mask by the holder 9.
Transport to. Reference numeral 12 is a gap sensor for detecting the distance between the focus surface of the projection system 5 and the surface of the substrate 3, and is, for example, an air microsensor or a photoelectric type sensor for detecting the distance by the reflected light from the substrate 3. Reference numeral 13 is a base for mounting the projection system 5, the illumination system 6, and the guide rail 8 in a fixed relationship.

[0008]

By the way, in the apparatus shown in the figure, the substrate stage 4 for step-moving the substrate 3 is used.
Also, the carriage 9 is equipped with the mask transfer device 11 and the mask stage 2 for exchanging the mask 1 corresponding to each printing target portion on the substrate 3, but in this case, the substrate stage 4 alone is, for example, 40 kg. Relatively heavy,
The load on the LAB 7 that floats the carriage 9 with air increases, and smooth scanning becomes difficult. Further, the carriage tends to have a flexible structure due to the demand for weight reduction, and the carriage 9 is deformed by the weight of the substrate stage 4 and the like,
When the distance between the mask 1 and the substrate 3 and the mirror projection system 5 changes and defocus occurs, or when the substrate stage 4 is moved to stepwise feed the substrate 3, the positioning reference of the mask 1 and the positioning reference of the substrate 3 are relative to each other. There has been a problem that a step occurs or overlaps between the divided and baked patterns due to the shift, or conversely, a gap is generated.

An object of the present invention is to provide a device manufacturing method capable of manufacturing a highly accurate device by step-and-scan exposure in view of the above problems of the prior art.

[0010]

To achieve this object, in the present invention, in a device manufacturing method using step-and-scan exposure, an original stage for holding an original plate and a substrate stage for holding a substrate are synchronized with each other during scan exposure. While each of them is moved by a separate driving source, and after the scan exposure, a step movement of the substrate with respect to the original plate is performed by the substrate stage to sequentially expose each of a plurality of regions on the substrate. To do.

The synchronization of the movements of the original plate stage and the substrate stage is achieved by, for example, driving the original plate stage and the substrate stage by measuring their position information through a laser interferometer and controlling them. be able to.

[0012]

According to this, the original plate stage and the substrate stage are moved in synchronization with each other by separate drive sources, so that it is not necessary to move a holder (carriage) for holding the original plate and the substrate stage. LAB for floating the carriage becomes unnecessary. Therefore, the problem of running instability due to insufficient rigidity of the air pads of the LAB is solved, and the holder is fixed to the base so that the scanning operation and the like can be performed by a more robust device. This reduces or prevents relative positional accuracy and defocus between the original plate and the substrate due to the deformation of the holder. Therefore, the scanning operation or the like is performed with high accuracy, and the device with high accuracy is manufactured.

Further, a stage for moving the original plate and the substrate, a motor and a control circuit, and a length measuring device for detecting the positions of the original plate and the substrate are originally necessary for aligning the original plate and the substrate. By using the product as it is or by modifying it to some extent, the device is manufactured by a simplified apparatus configuration. Further, in particular, since the step movement of the substrate is performed by the same substrate stage that moves the substrate during the scanning operation, highly accurate device manufacturing can be performed with a simpler and lighter device configuration.

Further, by arbitrarily setting the traveling speed ratio between the original plate and the substrate, an enlarging / reducing function which is not available in the conventional step-and-scan type exposure apparatus can be realized.

[0015]

Embodiments of the present invention will be described below with reference to the drawings. The parts common or corresponding to those of the conventional example are denoted by the same reference numerals. FIG. 1 shows the configuration of a mirror projection exposure apparatus for carrying out a device manufacturing method according to an embodiment of the present invention. In this figure, FIG. 2 shows the XZ of the device.
Whereas the cross section along the plane is shown, the cross section along the YZ plane is shown. However, the Y direction is the scanning direction during printing, and the Z direction is the vertical direction.

The apparatus shown in FIG. 1 is different from the apparatus shown in FIG. 2 in that the holder 9 is fixed to the base 13 and the stroke of the mask stage 2 and the substrate stage 4 in the Y direction is projected onto the mask 1 and the substrate 3 by an optical system. 5 is extended to such a degree that it can be scanned, and a control circuit 15 for synchronously controlling the movement amounts of the mask stage 2 and the substrate stage 4 in the Y direction during scanning is added. In FIG. 1, 16
And 17 are pulse motors for moving the mask stage 2 and the substrate stage 4 in the Y direction, and 18
Reference numerals 19 and 19 are length measuring devices such as laser interferometers for monitoring the positions of the stages 2 and 4, that is, the mask 1 and the substrate 3, respectively. Reference numerals 51, 52, and 53 are a trapezoidal mirror, a convex mirror, and a concave mirror, which form the projection optical system 5, respectively.

In the above structure, the control circuit 15 controls the number and cycle of the drive pulses to the pulse motors 16 and 17 based on the stage position information from the laser interferometers 18 and 19 during scanning exposure. The stages 2 and 4 are moved in synchronization with each other. As a method of this control, for example, the motor 16 is driven by a pulse of a constant cycle to move the mask stage 2 at a constant speed, and a drive pulse corresponding to the positions of the stages 2 and 4 measured by the laser interferometers 18 and 19 is used. The substrate stage 4 may be moved by supplying it to the motor 17.

In this case, the moving speeds of the stages 2 and 4 do not necessarily have to be the same, and may have an appropriate speed ratio. For example, the stages 2 and 4 can be scanned at different speeds (speed ratio ≠ 1) simply by making the output wavelengths of the laser interferometers 18 and 19 different. Further, the control circuit 15 may be more positively provided with the speed ratio varying means so that the stages 2 and 4 are driven at a speed ratio based on a command from a console keyboard or the like (not shown).

When the scanning speeds of the mask 1 and the substrate 3 are made different in this way, if the speed of the substrate 3 is made slower than the speed of the mask 1, the mask image is reduced on the substrate 3 in the traveling direction (Y direction). Transcribed. Further, when the speed of the substrate 3 is increased, the mask image is transferred onto the substrate 3 while being magnified in the Y direction. That is, the scanning type exposure apparatus can be provided with the enlargement / reduction function although it is only in the one-axis (Y) direction. If this function, especially the enlargement function, is used, for example, what is currently step-and-scan divided into four parts vertically (Y) and horizontally (X) from the point of the mask size is doubled in the vertical direction. By enlarging (substrate speed / mask speed = 2), it is sufficient to divide the mask in the same size into two in the vertical direction, and it is possible to improve the throughput of the apparatus by reducing the number of steps of substrate movement and mask replacement. Besides, you can reduce the time and effort required to make a mask from four to two.

[0020]

As described above, according to the present invention, the original stage and the substrate stage are moved by separate driving sources in synchronization with each other, so that the apparatus used for manufacturing is simple, lightweight and solid. Can be
Therefore, it is possible to perform the scanning operation and the like with high accuracy and manufacture the device with high accuracy. Further, as the drive source and the laser length measuring device, those originally required for aligning the original plate and the substrate, etc. can be used as they are or with some modification, so that the device can be manufactured with a simplified apparatus configuration. it can. In particular, since the step movement of the substrate is performed by the same substrate stage that moves the substrate during the scanning operation, highly accurate device manufacturing can be performed with a simpler and lighter device configuration. Further, by arbitrarily setting the traveling speed ratio between the original plate and the substrate, it is possible to realize the enlargement / reduction function which is not provided in the conventional step-and-scan type exposure apparatus.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram of a semiconductor printing apparatus according to an embodiment of the present invention.

FIG. 2 is a schematic configuration diagram of a semiconductor printing apparatus according to a prior application of the present inventors.

[Explanation of symbols]

1: photomask, 2: mask stage, 3: substrate,
4: substrate stage, 5: mirror projection system, 9: holder (carriage), 13: base, 15: control circuit, 16, 1
7: pulse motor, 18, 19: laser interferometer.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Makoto Miyazaki 53 Imaiue-cho, Nakahara-ku, Kawasaki-shi, Kanagawa Canon Inc., Kosugi Plant (72) Inventor Kunitaka Ozawa 3-30-2 Shimomaruko, Ota-ku, Tokyo Kyano (72) Inventor Hideki Yoshinari 53 Imaiue-cho, Nakahara-ku, Kawasaki-shi, Kanagawa Canon Inc. Kosugi Plant

Claims (2)

[Claims] 1. In a device manufacturing method using step-and-scan exposure, an original plate stage that holds an original plate and a substrate stage that holds a substrate during scan exposure are moved in synchronization with each other by separate drive sources.
By performing the step movement of the substrate with respect to the original plate by the substrate stage after the scan exposure,
A device manufacturing method comprising exposing each of a plurality of regions on the substrate in order. 2. The position information of each of the original stage and the substrate stage is measured via a laser interferometer, and the synchronization of the movement of the original stage and the substrate stage by the separate drive source during scan exposure is controlled. The device manufacturing method according to claim 1, wherein