JPH0994516A - Photoresistor coating device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To vary to a large extent the film thickness of a photoresistor layer by forming the diameter of a venting hole of a cover section almost equal to the outer diameter of an area on which the photoresistor layer is exposed. SOLUTION: The film thickness of a photoresistor layer 13 is formed to be the maximum on a position almost same as the position of the diameter of a venting hole 5 of a cover section 4. For instance, when the cover section 4 with the venting hole 5 having the diameter of approximately 160mm is used, the maximum value is demonstrated on the position of the diameter of 160mm of a master matrix 3 so that the difference of the film thickness from that of an inner peripheral section is approximately 10nm. Therefore, for instance, in the case of manufacturing a 12cm CD, the film thickness of the photoresistor layer 13 is varied to a large extent from the inner peripheral section to the outer peripheral section in the desired range by using the cover section 4 with a venting hole D having the diameter of 120mm. If means that the diameter of the venting hole 5 of the cover section 4 is formed almost equally to the outer diameter of an exposed area of the photoresistor layer 13.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a photoresist coating apparatus for forming a photoresist film on an optical disk master master or the like.

[0002]

2. Description of the Related Art Conventionally, compact discs (CD: Comp
When manufacturing an optical disk such as an act disk) or a laser disk (LD: Laser Disk), the shape of the recording pits is made uniform in order to make the recording / reproducing characteristics uniform over the entire recording information area of the optical disk. .

Depth of recording pit (CD: about 110n
Since m) is determined by the film thickness of the photoresist layer of the master disc, when forming the photoresist layer on the master disc, the area of the photoresist layer corresponding to the recorded information area of the optical disc obtained in the subsequent process. The various conditions such as the spin program of the photoresist coating device, the exhaust amount, and the viscosity of the coating liquid were controlled so that the film thickness of the film was uniform on the inner and outer circumferences.

However, a write-once CD (CD-R: Compact
When a replica of an optical disc with a large pre-groove (about 160 to 200 nm) is injection-molded (such as Disk-Recordable), the transferability of the recording pits on the outer periphery of the optical disc deteriorates and the recording / reproducing characteristics deteriorate. There was a problem.

Also in the conventional injection molding of a replica of CD or LD, if the injection time or the cooling time after molding is shortened in order to shorten the molding time, the optical disk outer peripheral portion is the same as the above CD-R. However, there is a problem that the transferability of the recording pits is reduced, the depth of the recording pits on the outer peripheral portion of the optical disc is reduced, and the recording / reproducing characteristics are deteriorated.

Therefore, the film thickness of the photoresist layer of the master disk is changed so as to increase from the inner peripheral portion to the outer peripheral portion to form the photoresist layer, and the shape (depth) of the recording pits on the outer peripheral portion of the optical disk is formed. Attempts have been made to increase (deep) the depth of the recording pit at the outer peripheral portion of the optical disc during injection molding.

[0007]

However, in order to form the photoresist layer so that the film thickness varies greatly from the inner peripheral portion to the outer peripheral portion, various factors such as the viscosity of the photoresist solution, the coating amount and the coating time are required. It was necessary to manage the conditions and to perform complicated spin program control, making it difficult to manufacture a master master having a stable film thickness difference between the inner and outer circumferences.

Further, the conventional photoresist coating apparatus is
The diameter of the vent hole of the lid was designed to be the same as or larger than that of the master disk so that the photoresist layer can be formed uniformly over the entire surface of the master disk. Normally, a master master having a diameter larger than the outer diameter of the recorded information area of the optical disc manufactured in the subsequent step is used (diameter 12
When producing a 0 mm CD, a master master with a diameter of 200 mm is used. ).

Therefore, the characteristics of the photoresist solution,
Even if the exhaust amount and the spin program are adjusted, a large difference in the thickness of the photoresist layer between the inner and outer circumferences of the master disc cannot be obtained, or only the photoresist layer on the outer periphery of the master disc becomes thick. Since the recorded information area of the optical disc manufactured in the subsequent step uses the middle circumference portion of the master master disk excluding the inner and outer circumference portions of the photoresist coating area, the recorded information area of the optical disc is formed of the photoresist layer. It was difficult to change the film thickness greatly.

[0010]

In order to solve the above-mentioned problems, in the invention according to claim 1 of the present invention, a lid is detachably attached to a device main body, and a drive device rotates the device. A turntable equipped with a circular substrate,
A nozzle for dropping a photoresist solution on the circular substrate, and an exhaust amount control valve for variably adjusting an exhaust amount of the coating chamber of the apparatus main body to form a photoresist layer on the circular substrate. In the resist coating apparatus, the diameter of the ventilation hole of the lid portion is substantially equal to the outer diameter of the region where the photoresist layer is exposed.

In the invention according to claim 2 of the present invention,
The photoresist coating apparatus according to claim 1, wherein a portion between the outer edge of the lid portion and the edge of the ventilation hole is inclined.

In the invention according to claim 3 of the present invention,
The photoresist coating apparatus according to claim 2, wherein the inclination angle of the portion between the outer edge of the lid portion and the edge of the ventilation hole is variable.

According to the photoresist device of the first aspect of the present invention, the film thickness of the photoresist layer of the master disk is changed from the inner circumference to the outer circumference in accordance with the diameter of the recorded information area of the optical disk to be manufactured. You can

According to the photoresist apparatus of the second aspect of the present invention, the film thickness difference between the inner and outer circumferences of the photoresist layer of the master master can be set to a desired value.

Further, according to the photoresist apparatus of the third aspect of the present invention, the film thickness on the inner and outer circumferences of the photoresist layer of the master master can be set to an arbitrary value by adjusting the exhaust amount.

[0016]

1 is a schematic diagram showing a first embodiment of a photoresist coating apparatus of the present invention. (A)
Is a state in which the movable portion 7 of the apparatus body is raised and the photoresist solution 10 is dropped, and (b) is a movable portion 7 of the apparatus body.
Shows that the turntable 2 is rotating at a high speed.

The apparatus main body 1 forming the coating chamber has a master master 3 detachably mounted in the center thereof, and a turntable 2 driven by a drive unit A11 is installed on the side of the turntable 2. On the other hand, a nozzle 6 which is rotated in the direction of arrow C by a driving device B12 and drops the photoresist solution 10 onto the entire surface of the master master 3 is installed, and a vent hole 5 is provided above the device main body 1. A flat donut-shaped lid portion 4 is detachably attached, and a movable portion 7 that moves up and down is installed.

Further, a plurality of ducts 8 are arranged below the apparatus body 1, and the exhaust amount is adjusted by the opening / closing amount of the exhaust amount adjusting valve 9. The displacement Q is expressed by the following equation (1). Q = αF (2ΔP / ρ) 1/2 (1) where, [rho is the minimum cross-sectional area of the density of the fluid, F is diaphragm (opening amount of the exhaust flow control valve 9), alpha is called flow coefficient, aperture ΔP is a pressure difference before and after the squeezing, which coefficient varies depending on the shape and the squeezing ratio. It can be seen from the equation (1) that the exhaust amount Q increases in proportion to the (1/2) th power of the pressure difference ΔP. In this example, the exhaust amount was not directly measured, but the pressure difference ΔP before and after the exhaust amount control valve 9 was measured.

In this embodiment, the thickness is 6 mm and the diameter is 200 m.
m master disc 3 was used. First, as shown in FIG. 1 (a), the movable part 7 having the lid part 4 mounted thereon rises in the direction of arrow A. The lid 4 is removed, the master master 3 is mounted on the turntable 2, and the lid 4 is mounted again.

The master master 3 installed on the turntable 2 is rotated at a low rotation speed of 100 rpm by the driving device A11, and the nozzle 6 is rotated on the master master 3 by the driving device B12 to discharge the photoresist solution 10. Then, the photoresist solution 10 is spread over the entire surface of the master master 3.

Next, as shown in FIG. 1 (b), the movable part 7 having the lid 4 mounted thereon descends in the direction of arrow B, and the master master 3
The turntable 2 mounted with is rotated at a high speed of 1000 rpm to form a photoresist layer 13. At this time, the air in the apparatus main body 1 is, as shown by the arrow D, the master master 3
Flows from the center to the outer circumference.

FIG. 2 is a film thickness distribution diagram of the photoresist layer 13 when the diameter of the ventilation hole 5 is changed. The pressure difference before and after the exhaust amount control valve 9 was fixed to 10 mmH ₂ O, and the photoresist solution 10 used was AZ1350 manufactured by Hoechst Co. diluted with a thinner to 20%.

As shown in FIG. 2, the film thickness of the photoresist layer 13 becomes maximum at a position approximately the same as the diameter of the vent hole 5. When the lid portion 4 having the diameter of the ventilation hole 5 of 160 mm is used, the maximum value is shown at the position of 160 mm in diameter of the master master 3 and the film thickness difference from the inner peripheral portion is about 10 nm (FIG. 2).
When the lid 4 having the ventilation hole 5 with a diameter of 120 mm is used,
The maximum value is shown at the position of 125 mm in diameter on the master disc 3.
The film thickness difference from the inner peripheral portion is about 15 nm (FIG. 2), and when the lid portion 4 having the vent hole 5 having a diameter of 80 mm is used, the maximum value is shown at the position of the master master 3 having a diameter of 80 mm. The film thickness difference from the peripheral portion was about 15 nm (FIG. 2).

Therefore, when a 12 cm CD (recording information area: diameter 44 mm to 118 mm) is manufactured, a lid 4 having a ventilation hole 5 with a diameter of 120 mm is used, and a 8 cm CD is used.
In the case of manufacturing (recorded information area: diameter 44 mm to 78 mm), if the lid portion 4 having the vent hole 5 with a diameter of 80 mm is used, the film thickness of the photoresist layer 13 can be set within a desired range. The thickness can be changed from the outer circumference to the outer circumference.

Next, a second embodiment of the photoresist coating apparatus of the present invention will be described. FIG. 3 is a schematic diagram showing a second embodiment of the photoresist coating apparatus of the present invention. The difference from the photoresist coating apparatus of the first embodiment is that, instead of the flat donut-shaped lid portion 4, an inclined lid portion 14 having an inclined portion in which the position of the vent hole 5 is higher than the outer edge portion by a height h. Was used. Other configurations are the same,
The procedure for applying the photoresist solution 10 onto the master master 3 and the rotation speed of the turntable 2 are also the same as those in the first embodiment.

FIG. 4 shows the photoresist layer 13 when the height h from the outer edge of the vent hole 5 of the inclined lid portion 14 is changed.
FIG. The vent hole 5 has a diameter of 120 mm, the pressure difference before and after the displacement control valve is fixed to 10 mmH ₂ O,
As a photoresist solution 10, AZ135 manufactured by Hoechst
0 was diluted to 20% with thinner and used.

As shown in FIG. 4, as the height h of the vent hole 5 increases, the difference in film thickness between the inner peripheral portion and the outer peripheral portion (around 120 mm in diameter) of the photoresist layer 13 decreases. Therefore, the difference in the film thickness between the inner and outer circumferences of the photoresist layer 13 can be set to a desired value by properly using the inclined lid portions 14 having different heights h of the ventilation holes 5. Further, by using the inclined lid portion 14, the splashing of the photoresist solution scattered from the glass master disk is reduced, and there is also an effect of reducing the film thickness unevenness in the circumferential direction.

FIG. 5 is a film thickness distribution chart of the photoresist layer 13 when the exhaust amount is changed by using the inclined lid portion 14. The sloped lid portion 14 has a height h of 40 mm and a diameter of the ventilation hole 5 of 120 mm. As the photoresist solution 10, AZ1350 manufactured by Hoechst Co. is used as a thinner 20.
% Was used.

As shown in FIG. 5, as the pressure difference (exhaust amount) before and after the exhaust amount control valve 9 increases, the film thickness on the inner and outer peripheries of the photoresist layer 13 increases. Therefore, the photoresist layer 13 having a desired film thickness can be formed only by adjusting the exhaust amount without changing the concentration of the photoresist solution, the rotation speed of the turntable, and the like.

[0030]

As described above, the photoresist coating apparatus of the present invention is manufactured without controlling the various conditions such as the viscosity of the photoresist solution, the coating amount and the coating time, and performing complicated spin program control. The film thickness of the photoresist layer of the master disc can be changed from the inner peripheral portion to the outer peripheral portion in accordance with the diameter of the recorded information area of the optical disc.

Further, according to the photoresist device of the present invention, the film thickness difference between the inner and outer circumferences of the photoresist layer of the master master can be set to a desired value.

Further, according to the photoresist device of the present invention, the film thickness on the inner and outer circumferences of the photoresist layer can be set to an arbitrary value by adjusting the exhaust amount.

[Brief description of drawings]

FIG. 1 is a schematic diagram showing a first embodiment of a photoresist coating apparatus of the present invention. (A) A state in which the movable part of the apparatus main body is raised and the photoresist solution is dropped. (B) A state in which the movable portion of the device body is lowered and the turntable is rotating at high speed.

FIG. 2 is a film thickness distribution diagram of a photoresist layer when the diameter of a ventilation hole is changed.

FIG. 3 is a schematic diagram showing a second embodiment of the photoresist coating apparatus of the present invention.

FIG. 4 is a film thickness distribution chart of the photoresist layer when the height h from the outer edge portion of the vent hole of the inclined lid portion is changed.

FIG. 5 is a film thickness distribution chart of the photoresist layer when the exhaust amount is changed by using the inclined lid portion.

[Explanation of symbols]

 1 Device Main Body 2 Turntable 3 Master Master 4 Lid 5 Vent 6 Nozzle 7 Movable 8 Duct 9 Exhaust Control Valve 10 Photoresist Solution 11 Driver A 12 Driver B 13 Photoresist Layer 14 Inclined Lid

Claims (3)

[Claims] 1. A device main body to which a lid having a vent hole is detachably mounted, a turntable which is rotated by a driving device to mount a circular substrate, and a nozzle which drops a photoresist solution onto the circular substrate. An exhaust volume control valve for variably adjusting the exhaust volume of the coating chamber of the apparatus body,
In a photoresist coating apparatus for forming a photoresist layer on the circular substrate, the diameter of the vent hole of the lid portion is substantially equal to the outer diameter of the region to which the photoresist layer is exposed, the photoresist coating apparatus. . 2. The photoresist coating apparatus according to claim 1, wherein a portion between the outer edge of the lid portion and the edge of the ventilation hole is inclined. 3. The photoresist coating apparatus according to claim 2, wherein the inclination angle of the portion between the outer edge of the lid and the edge of the ventilation hole is variable.