JPH0442449A - Developing device for disk - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a developing device for a disk, and more particularly to an improvement in a developing device for an optical disk that develops a resist plate after exposure to form exposure grooves.

(Prior art) In the step of manufacturing the standby of the previous disk master, the exposure step of exposing a resist plate coated with resist on a glass plate and the development step of developing the exposed resist board determine the groove shape of the standby. This is an important process.

The Ar'' laser used in the exposure process is easily affected by disturbances such as temperature and humidity, and it is difficult to maintain a constant groove shape even when exposed with the same amount of light.
There is also a variation in the light amount of the r'' laser itself of about several percent.

Therefore, there is a development method in which the groove shape after development is made constant by adjusting the development time in the development step after the exposure step. In this development method, while developing the resist plate, He-N is applied to the resist plate in a direction perpendicular to the exposed surface.
e When the laser beam is irradiated, the exposure grooves formed over time by development become a diffraction grating, and the amount of diffracted light of the laser beam obtained by this diffraction grating is monitored, and development is continued until this value reaches the set amount of diffracted light. It is something to do.

As shown in FIG. 2, a conventional developing device of this type includes a chucking table 3 on which an exposed resist plate 1 is suctioned and mounted using vacuum air with the exposed surface 1a facing upward, and a chucking table 3, as shown in FIG. It is equipped with a rotary motor 5 that rotationally drives the pull 3 and a developer port 9 that is disposed above the center of rotation of the resist plate 1 that rotates once and drops the developer 7 onto the exposure surface la. The dropped developer 7 flows spirally from the center toward the outer edge due to the centrifugal force of the rotating resist plate l, thereby forming the exposed surface 1a.
The entire surface is developed (so-called spin development). Through such a post-exposure development process, a film coated on a glass plate IA is used, as shown in FIGS. 3(a) and 3(b), for example. As the development time elapses, the exposed portion of the resist IB is deeply eroded and an exposed groove IC is formed.

A He-Ne laser light source l] is arranged below the rotary motor 5, and this laser light source II emits a He-Ne laser beam (one point am shown in the figure) through a mirror 12 to the resist plate l.
The exposed side from below! It irradiates in a direction perpendicular to a. The He-Ne laser beam passes through the resist plate l, and the H
The 0th-order diffracted light in the irradiation direction of the e-Ne laser beam (indicated by the - dotted chain line) and the exposure groove I that is formed by development and becomes a diffraction grating.
The first-order diffracted light is diffracted into C (indicated by a two-dot chain line). And above the chucking table 3!
A diffracted light amount monitor 13 is provided to monitor the amount of the next diffracted light, and development is performed until the amount of diffracted light detected by the diffracted light amount monitor I3 reaches a set value.

FIG. 4 is a correlation diagram between the development time and the amount of diffracted light in such a development process, and shows that the exposure groove t changes as the development process progresses.
The shape of C, that is, the shape of the diffraction grating changes, and the amount of diffracted light changes, so the amount of diffracted light increases relatively rapidly immediately after the start of development, but once development progresses to a certain extent, the rate of increase in the amount of diffracted light slows down. are doing. Therefore, the amount of diffracted light for obtaining an exposure groove 1C having a predetermined shape is set in advance.

By performing development until the amount of diffracted light detected by the diffraction light amount monitor 13 reaches the set amount of diffracted light, exposure 7111c having a predetermined shape can be obtained.

However, in such a conventional developing device, 2
The developing solution 7 dropped on the rotating resist plate 1k spreads in a spiral shape while developing, so the resist plate
When the thickness of the developer 7 flowing thereon is seen along the radial direction, it changes in a wavy manner, and the transmittance in the transmission part of the He-Ne laser 11 changes, causing the amount of diffracted light to change. In this way, it is difficult to find a portion on the resist plate 1 where the varying thickness of the developer 7 is constant, resulting in variations in the groove shape for each disk.

(Object of the Invention) The present invention has been made with attention to the above-mentioned problems, and it is possible to keep the shape of the exposure groove constant in the development process even if the exposure amount fluctuates, and to An object of the present invention is to provide a disk developing device that can make the thickness of the liquid constant and reproduce exposure grooves on each disk with high precision.

(Structure of the Invention) In order to achieve the above object, the present invention immerses the exposed surface of a resist plate in a developer to form an exposure groove, and irradiates a laser beam in a direction perpendicular to the exposed surface of the resist plate. ,
When the laser beam passes through the resist plate, the exposure groove is used as a diffraction grating to detect the amount of diffracted light, and when the detected amount of light reaches a predetermined amount, development is terminated to form an exposure groove of a predetermined shape. A developing device for forming a disc.

a container containing n developer; a chucking table that adsorbs the upper surface of the resist plate so that the nkN optical surface faces the surface of the current liquid in the container; and a lifting mechanism that moves the chucking table up and down. It is equipped with

This elevating mechanism lowers the chucking table to a height such that only the exposed surface of the resist plate is immersed in the developer solution level during development, while raising the exposed surface of the resist plate from the developer solution level after development is completed. It is a feature.

Hereinafter, a preferred embodiment of the present invention will be described in detail with reference to the drawings.

FIG. 1 shows a configuration diagram of a disk developing device according to an embodiment of the present invention, and the same components as in the conventional example are given the same reference numerals and the explanation thereof will be omitted.

The characteristic points of this embodiment are that the container 15 containing the developer 7 and the resist plate 1 are used as the exposure surface! A is provided with a chucking table 17 that attracts the resist plate 1 so that it is positioned downward, and an elevating mechanism 19 that moves the chucking table 17 up and down. While lowering the chucking table 17 to a position 2 such that the developer 7 is immersed in the developer 7 at a position parallel to the water surface of 7 and the developer 7 does not go around to the side of the chucking surface lb located opposite to the exposure surface 1a, At the end of development, the chucking table 17 is raised to a position where the exposed surface 1a of the resist plate 1 is separated from the developer surface S.

The He-Ne laser I+ is disposed below the container 15, and the He-Ne laser beam irradiated from the laser beam 1 passes through the developer 7 through the mirror 12 and passes through the resist plate 1.
The light is incident from the exposed surface +a. In addition, the diffraction light amount monitor 13
is disposed above the container 15 at a position to monitor the first-order diffracted light obtained by using the exposure groove IC formed on the exposure surface 1a by development as a diffraction grating.

Next, the effect will be explained.

In the above configuration, the exposed resist plate l is placed on the exposed surface 1.
a facing down on the chucking table 17, and by driving the elevating mechanism 19, the exposed surface 1a is immersed in the developer 7, and the chucking surface (upper surface) located on the opposite side to the exposed surface 1a is ) The chucking table 17 is lowered to a position where the developer 7 does not go around to the lb side. As a result, development progresses with the passage of time, and exposure grooves IC are formed in the exposed area, forming a diffraction grating.

The resist plate 1 is irradiated with laser light emitted from the He--Ne laser light source 11, and as development progresses, diffracted light is generated by the diffraction grating. This diffracted light is detected by the diffracted light amount monitor 13, and the resist plate is pressed until a preset amount of diffracted light is obtained. is held in that position. When the set amount of diffracted light is obtained, the chucking table 17 is moved upward by driving the lifting mechanism 19, and the exposure surface ta is separated from the developer surface S, and development is stopped. Move on to the cleaning process.

When the amount of developer in the container 15 changes and the water level changes,
The elevating mechanism 19 is arranged such that the exposed surface la of the resist plate l is immersed in the developer 7 at a position parallel to the water surface of the developer 7, and
Developing solution 7 is placed on the chucking surface lb side opposite to a.
The chucking table 17 is configured to be lowered to a position where it does not turn around, and developer solution 7 is supplied from a developer supply device (not shown).

By determining the progress of development based on the amount of diffracted light monitored by the diffraction light amount monitor 13 in this manner, it is possible to form a groove shape in a constant manner even if the amount of exposure light in the exposure step is not appropriate. Moreover, the thickness of the developer 7 (the height from the bottom of the container I5 to the exposed surface 1a) is the same over the entire exposed surface + a of the resist plate l, so H
The dialysis rate of the e-Ne laser beam is uniform over the entire exposed surface 1a, and the diffracted light m does not vary due to variations in the thickness of the developer as in the conventional case. Therefore, the diffraction grating at any position By detecting the amount of diffracted light using the diffracted light amount monitor 13, it is possible to suppress variations in the groove shape of each disk based on the detected value, and to obtain stable reproducibility.

In addition, even during development, the developer 7 does not go around the chucking surface 1b of the resist plate 1, and the refractive index at the chucking surface 1b of the resist plate 1 is n=1 in the atmosphere, so the diffraction due to the developer 7 going around Changes in the refractive index of light can be prevented, and the amount of diffracted light can be monitored with high precision.

Furthermore, since the resist plate 1 is attracted to the chucking table 17 with the exposure surface 1a facing downward, it is possible to eliminate problems caused by dust adhering to the exposure surface 1a.

(Effects of the Invention) As explained above, according to the present invention, the resist plate is attracted to the chucking table so that the exposed surface faces downward, and development is performed while adjusting the height of the chucking table using the lifting mechanism. Because of the structure that allows this, even if the exposure amount fluctuates, the shape of the exposure groove can be kept constant in the developing process, and the thickness of the developer on the resist plate can be kept constant. It is possible to obtain the effect that the reproduction of the exposure grooves on each disk can be made highly accurate.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing an embodiment of a disk developing device according to the present invention, FIG. 2 is a block diagram of a conventional developing device,
Fig. 3(a), (bl is a diagram showing the process of forming exposure grooves with development time, and Fig. 4 is a correlation diagram between development time and amount of diffracted light. l...Resist plate, la...・Exposure surface, Ib...chucking surface, IC...exposure groove, 7...developer, I
b...Container, 17...Chucking table, 19
... Lifting mechanism patented item Ricoh Co., Ltd. Figure 1 Figure 3 (O) (b) B A B A Figure 2 Potato 4 Figure Moxibustion Time back

Claims (1)

[Scope of Claims] The exposed surface of the resist plate is immersed in a developer to form exposure grooves, and a laser beam is irradiated in a direction perpendicular to the exposed surface of the resist plate, and the laser beam is transmitted through the resist plate. A disk developing device that forms exposure grooves of a predetermined shape by detecting the amount of diffracted light that is diffracted using the exposure groove as a diffraction grating and ending development when the detected amount of light reaches a predetermined amount. , a container containing the developer, a chucking table that sucks the upper surface of the resist plate so that the exposed surface faces the developer surface in the container, and a lifting mechanism that moves the chucking table up and down. The elevating mechanism lowers the chucking table to a height such that only the exposed surface of the resist plate is immersed in the developer solution level during development, and raises the exposed surface of the resist plate from the developer solution level after development is completed. A disc developing device characterized by: