JPS6030018B2 - exposure equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an exposure apparatus for exposing a photoresist layer or a beam resist layer, and particularly for forming information tracks such as audio or video on a disk as bits (concave portions) or blocks (convex portions). The present invention relates to an exposure apparatus for photoresist layers used in various cases.

A stamper is obtained by a method such as plating from a disk recording master disk on which information tracks such as audio or video are formed in the above shape, and this stamper is transferred to easily produce a large number of copies in the form of a press. be able to.

FIG. 1 is a cross-sectional view showing the manufacturing process of the disk recording master, in which a, b, c, and d represent the order of progress of the process.

In the step shown in FIG. 1a, a thin metal layer 2 is deposited on a transparent substrate 1, such as glass. In the step shown in FIG. 2b, the metal thin layer 2 is selectively exposed using a laser beam 3 whose intensity is modulated by an information signal, and is melted and evaporated to form a bit 21. In this way, an information track is formed. be done. Next, as shown in FIG. 1c, a photoresist 4 is uniformly applied onto the disk, and the photoresist 4 is exposed from the side of the transparent substrate 1 to light 6, for example, light from a mercury lamp. The thin metal layer 2 blocks the light 5, the bits 21 transmit the light 5, and the photoresist 4 is exposed. Here, if the photoresist 4 is of a negative type (a type in which a portion exposed to light remains), when it is developed, a resist button 41 corresponding to the bit 21 is formed as shown in FIG. 1d. By the way, some photoresists do not undergo photochemical reactions in the air because they are hindered by the air.

For example, in some commercially available negative-tone photoresists, oxygen in the air inhibits the reaction, so generally speaking, oxygen must be kept in a vacuum at an atmospheric pressure of 1/2 Tom (0.667m) or less. For example, there are photoresists whose photochemical reactions are inhibited.

Conventionally used devices for exposing such photoresists include exposing the photoresist in a vacuum container, or filling an airtight container with an inert gas and exposing the photoresist in the inert gas. There were devices such as However, for example, a video disc with a diameter of 14 inches (35 inches)
In order to expose a disk about 6 inches in size, a large vacuum container or a large airtight container is required, and problems such as sealing make the exposure apparatus large and difficult to manufacture. Furthermore, even if the vacuum container was made of metal to increase its strength so that it could withstand the pressure difference between the inside and outside of the container, there were drawbacks such as the need to use a transparent material for the part into which the exposure light is admitted. The present invention aims to eliminate the above-mentioned drawbacks of conventional exposure apparatuses, and provides an exposure apparatus that can perform exposure without using a high vacuum container or an airtight container.

To achieve this objective, the present invention rotates a video disc as a recording medium and flows an inert gas from the center of the video disc toward its outer periphery to form a film of inert gas on the surface of the video disc. However, the photoresist is exposed to light while being isolated from air, and will be described in more detail with reference to the drawings below. FIG. 2 is a sectional view showing an embodiment of the present invention, and FIG. 3 is a plan view showing an example of the flow of inert gas in the embodiment shown in FIG.

In these drawings, the same reference numerals as those in FIG. 1 indicate the same or equivalent parts, 6 is a motor, 7 is a dinner table rotated by the motor 6, and 8 is a nut for mounting a video disc recorder on the turntable 7. The video disk recording disk having the photoresist layer 4 is shown in FIG.
The one in the process indicated by is fixed to the turntable 7 with a nut 8. 9 is an inert gas inlet, 10' is a back plate, 11 is an inert gas supply port, 11 is an inert gas, 111 is an inert gas streamline, 12 is a filter, 13 is a gas pipe, 14 is an exhaust port, 15 is a side plate, 16 is a husband plate, 17
is a sealed bearing.

After dust is removed from the inert gas, such as nitrogen gas, by a filter 12, the gas passes through a gas pipe 13 and reaches the surface of the photoresist 4 of the disk from an inlet 9.

When the motor 6 is rotated in this state, a laminar flow of surface inert gas having streamlines 111 as shown by dotted lines in FIG. 3 is generated on the surface of the rotating disk. This laminar flow is due to the viscosity of the inert gas and centrifugal force. Since the rotating disk and the back plate 10 are close to each other, the inert gas present therebetween is forced outward in the radial direction by centrifugal force. By sequentially supplying the inert gas 1101 to the surface of the photoresist 4 by applying a suitable pressure, for example, a pressure of about 1 to 2 atmospheres (gauge pressure), the photoresist 4 is heated.
A laminar flow of inert gas 110 is continuously formed on the surface of
A film of inert gas 110 is formed on the surface of the photoresist 4 to isolate the photoresist 4 from air. An exhaust row 4 is provided in a part of the weight body structure surrounding the rotating disk,
This prevents turbulence from occurring. Further, when the substrate 1 was a glass plate, the gap between the back plate 10 and the photoresist 4 was set to 1 or 2 to obtain good results. Furthermore, in order to prevent the light 5 from being reflected again on the surface of the back plate 10 facing the photoresist 4, it is better to lower the reflectance by making it black or the like. In order to prevent the surface laminar flow of the inert gas 110 from being disturbed from the outside, the rotating disk is surrounded by a ridge formed by a back plate 10, a side plate 15, and a husband plate 16 at least partially made of a transparent material. It's better to leave it there.

Further, a sealed bearing 17 is provided at the sliding portion between the shaft of the motor 6 and the back plate 10, but a commercially available sealed radial bearing is sufficient as the bearing 17. It is most convenient to use nitrogen gas as the inert gas 110. As explained above, according to the present invention, photoresist can be exposed without the need for a vacuum container or an airtight container to cut off air, and even if the recording medium becomes large like a video disk, exposure The device can be constructed with a relatively small size and simple structure. Further, it has the advantage that it is not necessary to maintain the airtightness of the container all the time, maintenance is convenient, and nitrogen gas used as an inert gas is easily available. Therefore, according to the present invention, it is possible to obtain an exposure apparatus that has a simple structure and is convenient to use.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing the manufacturing process of a disk recording master, FIG. 2 is a sectional view showing an embodiment of the invention, and FIG. 3 is a plan view showing an example of the flow of inert gas in the invention. . In the figure, 1 is a transparent substrate, 2 is a metal thin layer, 21 is a bit, 4 is a photoresist, 6 is a resist exposure light, 6 is a motor, 7 is a turntable, 1 is a back plate, 11
111 is an inert gas streamline. Note that the same reference numerals in each figure indicate the same or equivalent parts. Figure 1 Figure 2 Figure 3

Claims (1)

[Claims] 1. A turntable on which a substrate on which a photoresist layer or a beam resist layer is formed is mounted and the substrate is rotated;
a backplate having a surface facing sufficiently close to the surface of said photoresist layer or beam resist layer; An exposure apparatus comprising: an inert gas supply mechanism for creating a surface laminar flow of active gas; and a light source device for exposing the photoresist layer or beam resist layer. 2. The exposure apparatus according to claim 1, wherein the inert gas is formed of nitrogen gas.