JPH0749910B2 - Device for heating and drying optical disc masters - Google Patents

Description

TECHNICAL FIELD The present invention relates to a heating / drying device for an optical disc master that radiatively heats an optical disc master using a far infrared ray or an infrared heater.

BACKGROUND ART A so-called heat tunnel shown in FIG. 6 is known as a conventional heating and drying apparatus. In this heating / drying apparatus, the object 61 to be heated is transferred by the belt conveyor 62 and the object 61 to be heated is transferred by the ambient temperature in the tunnel when passing through the tunnel constituted by the heater 63.
It is configured to be heated and dried.

In this heating / drying device, since the surface to be heated of the object to be heated 61 is placed on the belt conveyor 62 and heated and dried from above, when the optical disk master is the object to be heated, the There is a concern that the heated surface of the optical disc master may be contaminated by impurities such as particles that settle down under the influence of the dust, and dust-proof measures are desired.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a heating / drying device for an optical disc master that can perform a heating / drying process while reliably protecting the heated surface of the optical disc master from contamination by impurities such as dust and particles. .

A heating / drying apparatus for an optical disk master according to the present invention comprises: a rotation driving means for supporting and rotating an optical disk master made of a glass master coated with a photoresist such that the coated surface of the photoresist is the lower surface; and the optical disk master. Heating means for radiantly heating the optical disc master, which is arranged in parallel below the photoresist coat surface so as to face the photoresist coat surface, and blowing means for sending clean air along the photoresist coat surface of the optical disc master. It is characterized by having.

Example Hereinafter, an example of the present invention will be described in detail with reference to the drawings.

FIG. 1 is an external view of an apparatus showing an embodiment of the present invention, and FIG. 2 is a structural view thereof. In each of these figures, a glass master disk 1 which is an optical disk master disk is coated with a photoresist on one surface thereof, and is supported by a spindle 2 so that the surface coated with the photoresist is the lower surface. The spindle 2 is rotationally driven by a spindle motor 4 housed in a housing 3. Spindle 2 and spindle motor 4
Is attached to a spindle base 5, and is driven by a spindle base drive motor 8 to be transferred on a main base 7 while being guided by a linear slide 6, so that the spindle 2 is mounted on the upper surface of a housing 3 and the glass master 1
It moves between the position shown by the solid line and the position shown by the alternate long and short dash line along the long hole 9 formed to have a length substantially equal to the radius of.

The position indicated by the solid line of the glass master 1 and the spindle 2 is the standby position, and the glass master 1 is loaded and unloaded and the cooling process after the heating process is performed at this standby position. The position indicated by the alternate long and short dash line is a heat drying (baking) position, and the heat drying process is performed at this position. This device is installed in a horizontal airflow type clean bench as an air blower and used in a clean room. The left side of the figure is the worker side and the right side is the clean bench side. Due to this positional relationship, it is possible to minimize the contamination in the drying process, which is the weakest against contamination. That is, in a clean room, when a worker who is a dust source always works in the leeward direction and particles that settle down under the influence of gravity, a clean air flow is indicated as shown by an arrow in FIG. And flush it out,
By setting the heated surface of the glass master 1 to the lower side, and for dust generated from the mechanical section, the inside of the housing 3 is exhausted by the exhaust tube 10 to prevent contamination. There is. In addition, the upper surface of the housing 3 is in principle the same plane except that there are some openings, thereby preventing accumulation of contaminant particles and facilitating cleaning.

A part of the upper surface of the housing 3 on the clean bench side is a radiant heat shielding plate 12 having a substantially fan-shaped opening 11. The radiant heat shielding plate 12 is made of, for example, stainless steel, and has a housing 3
It may be configured integrally with. A heater unit 14 including a far infrared ray or infrared heater element 13 for radiatively heating the glass master 1 through the opening 11 is arranged below the opening 11. In this heater unit 14, as is particularly clear from FIG. 3, the heater element
13 is attached to the heater mounting plate 15 so as to face a part of the radius region of the glass master 1 in the heating and drying position, and is fixed to the outer plate 16 by a support body (not shown). A radiant heat shielding plate is provided above the outer plate 16 via a spacer 17 that also serves as heat insulation.
12 is fixed. The jacket portion formed by the heater mounting plate 15 and the outer plate 16 is exhausted by the exhaust tube 18, whereby the heater element 13 is kept at a negative pressure so as not to generate heat diffusion type contamination due to heating.
Further, by exhausting the heater unit 14, unnecessary heat transfer is prevented and the temperature of the device is prevented from rising. The temperature of the heater element 13 is measured by a thermocouple (not shown) attached to the heater element 13.

A radiation thermometer 19 is provided inside the housing 3, and the radiation thermometer 19 measures the surface temperature of the glass master 1 through a measurement window 20 formed on the upper surface of the housing 3. The measurement output of the radiation thermometer 19 is supplied to the controller 21. The controller 21 is composed of, for example, a microcomputer, and is a series of controls for heating and drying the glass master 1 such as temperature control of the heater element 13, start and stop of rotation of the spindle 2 and transfer control of the spindle 2. Do.

Next, the basic sequence of the heating and drying processing procedure executed by the processor of the controller 21 will be described with reference to the flowchart of FIG.

When the device power is turned on, the processor first
Start preheating of heater element 13 (step
S1). The temperature of the heater element 13 is set to 215 ° C., for example, and the preparation is completed at 215 ± 5 ° C. The purpose of preheating is that the time constant of heating the heater is large,
This is because the heating and drying time becomes long if the heater element 13 is not heated in advance, and the temperature is measured by the thermocouple attached to the heater element 13.

When the glass master 1 is set on the spindle 2 and then the start switch (not shown) is turned on (step S
2), the processor sets the spindle 2 to, for example, 3 [rp
m.] (step S3), the temperature of the heater element 13 is set to the set temperature T ₁ based on the measured output of the thermocouple.
When it is detected (step S4), the spindle base drive motor 8 is drive-controlled to advance the spindle 2 from the standby position to the heating / drying position (step S5). Then, at this position, the photoresist of the glass master 1 is heated and dried by radiant heating of the heater element 13 (step S6).

In this heating and drying step, the surface temperature of the glass master 1 is determined to be a predetermined temperature T ₂ , for example, based on the measurement output of the radiation thermometer 19.
When it is detected that the temperature has reached 90 ± 0.5 ° C (step S7),
The spindle 2 is retracted from the heating / drying position to the standby position by driving and controlling the spindle base drive motor 8 (step S8). At this standby position, the glass master 1 after heating is cooled (step S9). In this cooling process, the surface temperature of the glass master 1 is set to a predetermined temperature T ₃ , for example 55, based on the measurement output of the radiation thermometer 19. When it is detected that the temperature becomes ± 0.5 ° C. or less (step S10), the rotation of the spindle 2 is stopped (step S11). And
By removing the glass master 1 from the spindle 2,
A series of processing is completed.

In the heating and drying step described above, the infrared rays generated by the heater element 13 have the property of traveling straight in the same manner as visible light, reach the opposite glass master 1 through the opening 11 of the radiant heat shielding plate 12, and reach the photoresist. It is absorbed and generates heat. The calorific value per unit area is generally determined by various conditions such as the time facing the heater element 13, the calorific value distribution of the heater element 13 itself, and the cooling efficiency received from the surroundings. Therefore, when the radiant heat shielding plate 12 is not provided, the temperature distribution on the resist surface of the glass master 1 is low at the central portion and becomes higher toward the outer periphery, as shown in FIG. It becomes low again due to the large cooling effect. On the other hand, a radiant heat shield plate 12 having an opening 11 is provided, and the heat generation amount per unit area is corrected by the substantially fan-shaped shape of the opening 11 including all the factors related thereto. As shown in a), it is possible to obtain a uniform temperature distribution over the entire surface from the inner circumference to the outer circumference. FIG. 5 (c) shows the characteristics of the conventional device shown in FIG.

EFFECTS OF THE INVENTION As described above, in the heating / drying apparatus for the optical disc master according to the present invention, the optical disc master made of the glass master coated with the photoresist is carried so that the photoresist coating surface is the lower surface, and is rotationally driven. Rotation driving means, heating means for radiatively heating the optical disk master, which is arranged in parallel below and facing the photoresist-coated surface of the optical disk master, and clean air is blown along the photoresist-coated surface of the optical disk master. Since it is a structure that has a blowing means for sending, it can perform heat treatment while sending clean air because it is radiant heating, and because it is a heat treatment with the heated surface of the optical disc master down, dust, particles, etc. The surface to be heated can be reliably protected from contamination by the impurities.

Further, since the inside of the housing is exhausted, the heated surface of the optical disk master can be protected against dust generated from the mechanical section.

[Brief description of drawings]

FIG. 1 is an external view of an apparatus showing an embodiment of the present invention, FIG. 2 is its structural view, FIG. 3 is an enlarged sectional view of a heater unit in FIG. 2, and FIG. 4 is heat drying executed by a processor. 5 is a flow chart showing the basic sequence of the processing procedure of FIG. 5, FIG. 5 is a characteristic diagram showing the temperature deviation of each radius from the reference temperature, FIG. 6 (A) is an external view of the conventional device, and FIG. . Explanation of symbols of main parts 1 …… Glass master, 2 …… Spindle 4 …… Spindle motor 8 …… Spindle base drive motor 10,18 …… Exhaust tube 11 …… Opening part, 12 …… Radiation heat shielding plate 13… Heater element 14 Heater unit 19 Radiation thermometer, 21 Controller

Claims (3)

[Claims] 1. A rotation driving means for supporting and rotating an optical disk master made of a glass master coated with a photoresist such that the coated surface of the photoresist is a bottom surface.
A heating means for radiantly heating the optical disk master arranged parallel to the photoresist coated surface of the optical disk master, and a blowing means for sending clean air along the photoresist coated surface of the optical disk master. When,
A heating / drying device for an optical disk master, which is provided with: 2. A transfer means for transferring the rotation drive means in a horizontal direction between a first position for holding the optical disk master on standby and a second position for heating and drying, and the rotation drive means. 2. The heating / drying device for an optical disk master according to claim 1, wherein the optical disk master is constantly driven to rotate while being transferred by the means and while being positioned at the second position. 3. The heating / drying apparatus for an optical disk master according to claim 2, wherein the air blower sends the clean air in a direction from the second position to the first position.