JPS6077424A - Mask securing device of x-ray exposure apparatus - Google Patents

Abstract

PURPOSE:To secure a mask in high reliability by providing an electromagnet to a member for mounting the mask, and attracting the mask of a magnetic substrate. CONSTITUTION:A mask chuck 1' is composed of a magnetic material, a coated wire 15 is wound on the outer periphery to form a coil 15. When the coil 15 is energized, the chuck 1' becomes a cylindrical magnet. When a mask substrate 6' is composed of a ferromagnetic material, the chuck l' attracts fixedly by the magnetic force the mask 6'. The attracting force can be arbitrarily controlled by the number of turns of the coil 15 and the current value, and when the current is interrupted, the attraction can be released. With this structure, no vacuum is used, a loss of He leakage or a vibration of the mask 6' due to the variation in the attracting force and the leakage amount can be eliminated. Ultrafine dust particles in the He are not attracted to the attracting surface of the mask due to He leakage current, and the X-ray exposure mask can be reliably secured.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to an apparatus for mounting and fixing a patterned mask in an X-ray exposure apparatus.

[Background of the invention]

Conventionally, a vacuum suction method has generally been used for a mask fixing device of an exposure apparatus.

In exposure using visible light to near ultraviolet light, the base material of the mask used for exposure is glass with a thickness of 711 mm.
The mask can be suctioned and fixed with uniform force by vacuum suction, and if the suction surface of the mask chuck O is flat, almost no distortion will be caused to the mask.

The first factor shows a vacuum suction device for a mask in the prior art. A groove 2 is provided on the entire circumference of the mask suction surface 3 of the cylindrical mask chuck l, and the groove 2 is connected to a vacuum pump (Fig. The mask is made by adhering a membrane 78 with a thickness of several μm to a ring-shaped base material 6, and forming a pattern (not shown) on this membrane 7.The above base material 6 is Conventionally, a structure in which the central portion of a silicon wafer is punched out is generally used.

The wafer 10 to be subjected to pyrography transfer and the mask are directly opposed to each other with a gap g (usually several μm to several tens of μm), and the membrane 7 is irradiated with X-rays 98 from an X-ray source (not shown). The upper pattern is printed and transferred onto the wafer 10.

In this setup, the atmosphere 8 through which the X-rays 9 pass
is compensated for by a wall 12 and filled with helium gas to prevent X-ray attenuation.

The conventional mask mounting and fixing device for an X&exposure device described above has the following technical problems.

(a) It is difficult to completely eliminate leakage between the mask chuck 1 and the mask base material 6, and some helium is drawn into the vacuum and leaks as shown by arrow 13. This wastes helium.

(Li) The internal pressure fluctuates due to fluctuations in the vacuum adsorption force or fluctuations in the amount of leakage described above, and as a result, the membrane 7 vibrates, making the interval g unstable and causing misalignment or blurring of the transferred pattern image.

(c) Printing transfer is performed in a clean atmosphere, but it is difficult to guarantee that there will be no dust. If minute dust particles get mixed into the helium atmosphere 8 P3, they will not directly cause a serious problem if they are just floating around in the air, but they will ride the leakage flow shown by arrow 13 and leak into the mask chuck. 1 and the mask base material 6, there is a risk that the next mask will be distorted during the next printing operation.

[Purpose of the invention]

The present invention has been made to solve the problems of the prior art described above,
The purpose of this is to eliminate the risk of helium being leaked uselessly, and to prevent dust from forming in the helium atmosphere by causing vibrations to the membrane due to fluctuations in the vacuum adsorption force or fluctuations in the leakage flow rate, which may adversely affect the transferred pattern. There is no risk of particles being absorbed by the C mask due to leakage airflow.
To provide a mask fixing device for an X-ray exposure device.

[Summary of the invention]

In order to achieve the above object, the fixing device of the present invention irradiates the wafer with X-rays emitted from an X-ray source through a mask, and prints a pattern provided on the mask onto the wafer. In an X-ray exposure apparatus, a magnet is provided on the member to which the mask is mounted, and a magnet is provided on the base material 7il- of the mask.
It is characterized in that it is constructed using a magnetic material, and that the mask can be attracted and fixed by the magnetic force of the electromagnet.

[Embodiments of the invention]

Next, one embodiment of the Kienori j will be described with reference to FIG.

A mask kayak 1' is made of a magnetic material, and a coil 15 is formed by winding a covering layer wire 147j around its outer periphery. When the coil 15 is energized, the mask chuck 1' becomes a cylindrical magnet.

On the other hand, the mask base material 6' is made of a magnetic material. This allows the mask chuck 1 to magnetically attract and fix the mask. The attraction force can be arbitrarily controlled by the number of turns of the coil 150 and the current value, and the attraction force can be canceled by cutting off the current.

As a different embodiment from the above, the mask base material 6 may be made of a non-magnetic material, and a reinforcing ring made of a magnetic material may be attached thereto. In short, by using a magnetic material for at least a portion of the base material portion of the mask, the function of magnetic attraction can be achieved.

FIG. 4 shows an embodiment different from the above. Mask chuck 1' and covered electric wire 14 with the same drawing reference numbers as in Fig. 3
．． Coil 15 is the same or similar component as in the previous embodiment (FIG. 3). In this embodiment, a pipe 17 is wound between the coil 15 and the suction surface 16 so that cooling water can be circulated. According to this embodiment, there is no possibility that heat generated due to energization of the coil 15 will be transmitted to the mask via the mask adsorption surface 16 and cause thermal distortion.

Although not shown, the support part of the mask chuck 1' and the coil 1
A cooling pipe may also be provided between the 5 and 5. This eliminates the possibility that the heat generated by the coil 15 will adversely affect the supporting state of the mask chuck 1'.

In the embodiment described above, since the mask base material 6 is suctioned and fixed without using vacuum suction, there is no risk of leakage of helium and no risk of wasting helium. Furthermore, there is no risk of vibrations being imparted to the membrane due to fluctuations in vacuum suction force or leakage helium flow rate. Furthermore, there is no risk that minute dust particles floating in the helium atmosphere will be sucked into the mask suction surface by the helium leakage flow and adhere to the mask.

〔Effect of the invention〕

As described in detail above, according to the present invention, there is no risk of helium leaking out uselessly, there is no risk of adverse effects on the transferred pattern due to fluctuations in vacuum adsorption force or leakage flow rate, and there is no risk of helium floating in the helium atmosphere. There is also no risk that minute dust particles caused by leakage airflow will be sucked in and adhered to the mask suction surface.

[Brief explanation of the drawing]

FIG. 1 is a vertical sectional view of an example of a conventional mask suction device, FIG. 2 is a vertical sectional view showing a state in which a mask is suctioned and fixed by the above mask suction device, and FIG. 3 is an X-ray exposure device of the present invention. a partial vertical cross-sectional view of an embodiment of the mask fixing device of;
FIG. 4 is a partial sectional view of an embodiment different from the above. 1.1'...Mask chuck. 2...Groove, 3...Adsorption surface. 4...Communication path, 5...Pipe. 6.6'...Basis of the mask. 7... Membrane, 8... Helium atmosphere. 9..., X-ray, 10... wafer. 12...Wall, 13...Helium leakage flow. Figure 4

Claims (1)

[Claims] 1. In an X-ray exposure device that irradiates X-rays emitted from an X-ray source onto a wafer through a mask and prints and transfers a pattern provided on the mask onto the wafer. X, characterized in that an electromagnet is provided on the member to which the mask is attached, and the base material of the mask is made of a magnetic material, so that the mask can be attracted and fixed by the magnetic force of the electromagnet. Mask fixing device for line exposure equipment. 2. X according to claim 1, wherein the magnetic material used for the base material of the mask is formed into a plate shape and adhered to the base material portion of the mask. Fixing device for line exposure equipment. 3. The member for attaching the mask is provided with a flow path through which a cooling fluid flows.