JPH05234874A - Processor - Google Patents

Abstract

(57) [Summary] [Purpose] Exhaust the inside of the device favorably to prevent the mist-like treatment liquid from flying to the front and back surfaces of the object to be treated. An inner cup 29 surrounds a lower portion of a wafer holding portion of a spin chuck 21 which holds a wafer W horizontally and rotates, and an outer cup 30 surrounds the outer sides of the spin chuck 21 and the inner cup 29. .. The exhaust port 32 is opened in the inner annular flow passage 15 of the inner and outer double annular flow passages defined by the partition member 34 standing upright on the bottom of the outer cup 30. The outer peripheral flow path 29 d hangs from the outer periphery of the upper portion of the inner cup 29 to partition the annular flow path into an outer annular flow path 36 and an intermediate annular flow path 37.
The flow passage areas S1 and S2 of 7 are set equal to each other.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a processing apparatus for supplying a processing liquid such as a resist liquid onto the surface of a plate-shaped object to be processed such as a semiconductor wafer.

[0002]

2. Description of the Related Art When a processing liquid is applied to a plate-shaped object to be processed using a conventional processing apparatus of this type, the processing liquid that has been shaken off from the rotating object to be processed is splashed on the inner wall of the cup to be covered. In order to prevent adherence to the surface of the object to be treated, air is introduced from the upper opening of the cup (downflow in the clean room), for example, by exhausting air from the bottom of the cup, and the surface of the object to be treated is introduced. Generates an airflow that flows outward along.

A resist coating apparatus shown in FIG. 8 is conventionally known as this type of apparatus. This apparatus attracts and holds a semiconductor wafer W (hereinafter referred to as a wafer), which is an object to be processed, and spin-rotates a wafer horizontally held by the spin-chuck 51. The processing liquid is applied to the surface of the wafer W held on the spin-chuck 51. A processing liquid supply nozzle 52 for supplying and an annular inner cup 5 arranged so as to surround the spin chuck 51.
3 and an outer cup 54 that surrounds the spin chuck 51 and the inner cup 53 to prevent the processing liquid from scattering, and constitutes a main part.

The inner cup 53 is formed on a cylindrical standing portion 53a which stands up from the bottom of the outer cup 54 and substantially surrounds the periphery of the spin chuck 51, and an upper end portion of the standing portion 53a. Horizontal part 53 that constitutes the upper surface 57
b, a slanted portion 53c that extends obliquely downward from the outer peripheral edge of the horizontal portion 53b and extends, and the slanted portion 53c.
And an outer peripheral portion 53d extending from the outer peripheral edge portion to the vicinity of the bottom portion of the outer cup 54. The outer cup 54 has a large opening at the top so that the wafer W can be taken in and out, and an exhaust port 55 and a drain port 56 are provided at the bottom. Also,
An annular partition member 58 is provided at the bottom of the outer cup 54 so as to surround the lower portion of the upright portion 53a.
The drainage port 56 is provided between the partition member 58 and the rising portion 53 a of the inner cup 53, and the drainage port 56 is provided near the inner wall of the outer cup 54.

When the inside of the outer cup 54 is evacuated through the exhaust port 55 in the conventional resist coating apparatus having the above-described structure, the air A introduced from the upper opening of the outer cup 54 is applied to the surface of the wafer W. After being radiated along,
It descends between the inner cup 53 and the outer cup 54, and between the outer peripheral portion 53d of the inner cup 53 and the partition member 58, the partition member 5
8 and the standing portion 53a are sequentially passed to reach the exhaust port 55 and exhausted. At the time of spin coating, the resist solution which is shaken off from the peripheral portion of the wafer W and scattered, hits the inner wall of the outer cup 54 and becomes a mist, flows radially along the surface of the wafer W and then descends as described above. It is conveyed in the flow of air A and is discharged together with air A from the exhaust port 55. Further, the resist liquid that has adhered to the inner wall of the outer cup 54 and is in the form of water drops descends along the inner wall, is accumulated at the bottom portion, and is discharged from the liquid discharge port 56.

[0006]

However, in the conventional device of this type, although the flow of the air A on the side where the exhaust port 55 is provided satisfactorily occurs, the position away from the exhaust port 55, particularly the exhaust port 55 The flow of the air A on the side opposite to 55 tends to be insufficient, and as a result, the resist solution in the form of a mist that hits the inner wall of the outer cup 54 is not conveyed completely downward, and splashes onto the surface of the wafer W. Then, there is a problem in that they adhere to each other and deteriorate the uniformity of the coating film. As a result of examination by the present inventors, the main cause of the shortage of the flow of the air A in the position away from the exhaust port 55 is an annular shape formed between the outer cup 54 and the outer peripheral portion 53d of the inner cup 53. It has been found that there is a difference in the flow passage area between the flow passage and the annular flow passage formed between the outer peripheral portion 53d of the inner cup 53 and the partition member 58. That is, in the conventional device, the diameter of the outer peripheral portion 53d of the inner cup 53 is equal to the diameter of the outer cup 54 and the partition member 58.
It is considered that since the outer flow passage has a larger flow passage area than the inner flow passage, the pressure loss caused by the outer flow passage is more remarkable as the distance from the exhaust port 5 increases.

Further, in the conventional apparatus of this type, since the diameter of the peripheral portion of the upper surface 57 of the inner cup 53 is smaller than the diameter of the wafer W, as shown in FIG. The air A that has flown around easily flows between the back surface of the wafer W and the upper surface 7 of the inner cup 53, and the resist liquid adheres to the back surface of the wafer W and the upper surface 57 of the inner cup 53, and then is dried to generate particles. There was a problem to do.

The present invention has been made in view of the above circumstances, and evacuates the apparatus satisfactorily to prevent a processing solution such as a mist-like resist solution from flying to the front and back surfaces of the object to be processed. Another object of the present invention is to provide a processing apparatus capable of performing good processing by preventing the processing liquid from adhering to the back surface of the object to be processed.

[0009]

In order to achieve the above-mentioned object, a first processing apparatus of the present invention is a rotation holding means for holding and rotating an object to be processed, and an outer cup surrounding the rotation holding means. An inner cup that stands up from the bottom of the outer cup to surround the lower part of the object to be processed holding portion of the rotation holding means, and an inner-outer double ring that is partitioned by a partition member that stands up at the bottom of the outer cup. The inner annular passage of the flow passage is provided with an exhaust port, and the outer peripheral portion hanging from the upper outer periphery of the inner cup divides the annular passage into an outer annular passage and an intermediate annular passage. The flow passage areas of the flow passage and the intermediate annular flow passage are set equal to each other.

Further, according to the second processing apparatus of the present invention, there is provided rotation holding means for holding and rotating the object to be processed, and an annular inner cup surrounding the object holding part of the rotation holding means. In the processing apparatus provided, an outer peripheral edge portion that extends outward in the radial direction according to the diameter of the object to be processed is formed on the outer peripheral edge portion of the upper surface of the inner cup.

In the present invention, the exhaust port may have any depth as long as it is open to the inner annular flow passage, but preferably a cylindrical flow rate interference part having the same diameter as the opening part of the exhaust port is provided. At the same time, it is better to form the depth of the flow rate interference portion as long as possible.

As long as the opening of the outer cup has a size that does not hinder the insertion and removal of the object to be processed, the opening edge may be simply cut, but preferably the opening edge is directed inward. It is better to form the upper opening edge that is folded back in a V shape or a U shape. The folding angle of the upper opening edge is, for example, 45 ° to 60 ° with respect to the horizontal plane.
It is better to set to.

[0013]

According to the processing apparatus of the first aspect of the invention configured as described above, when the inside of the outer cup is exhausted from the exhaust port,
The air introduced from the upper opening flows radially along the surface of the object to be processed, then descends between the inner cup and the outer cup, and the outer annular channel, the intermediate annular channel, and It flows in the order of the inner annular flow path, reaches the exhaust port, and is exhausted to the outside of the device. Since the flow passage area of the outer annular flow passage and the flow passage area of the middle annular flow passage are set to be equal to each other, the pressure loss due to the difference in flow passage area is eliminated, and at the position away from the exhaust port. Also, the air flow can be satisfactorily generated. Therefore, the treatment liquid that has hit the inner wall of the outer cup and becomes a mist can be satisfactorily conveyed by the air flow.
It is possible to prevent the particles from being discharged and fly to the surface of the object to be processed, and improve the uniformity of the coating film and the like.

Further, according to the processing apparatus of the second aspect of the present invention, the outer peripheral edge of the upper surface of the inner cup is extended outward in the radial direction in accordance with the diameter of the object to be processed. It is possible to prevent the air, which tends to go around from the portion toward the back surface side, on the back surface of the outer peripheral edge portion of the upper surface from which the inner cup extends. Therefore, it is possible to more reliably prevent the processing liquid from adhering to the back surface of the object to be processed or the upper surface of the inner cup and to prevent the generation of particles.

[0015]

Embodiments of the present invention will be described in detail below with reference to the drawings. This embodiment is applied to a resist coating / developing apparatus.

As shown in FIG. 1, the resist coating / developing apparatus includes a processing mechanism unit 10 in which a processing mechanism for performing various processes on an object to be processed, for example, a semiconductor wafer (hereinafter, simply referred to as a wafer) W is arranged, and a processing mechanism. Wafer W on unit 10
The main part is composed of a loading / unloading mechanism 1 for automatically loading and unloading.

The loading / unloading mechanism 1 includes a wafer carrier 2 for storing the unprocessed wafer W, a wafer carrier 3 for storing the processed wafer W, and an chuck for holding the wafer W by suction.
The wafer 4, the moving mechanism 5 for moving the arm 4 in the X, Y (horizontal), Z (vertical) and θ (rotation) directions, and the wafer W.
The alignment stage 6 in which the wafer W is aligned and the wafer W is transferred to and from the processing mechanism unit 10.
It has and.

The processing mechanism unit 10 is provided with a transfer mechanism 12 movably along a transfer path 11 formed in the X direction from the alignment stage 6. Transport mechanism 1
2 has a main arm 13 movably in Y, Z and θ directions.
Is provided. On one side of the transfer path 11, an adhesion processing mechanism 14 for performing an adhesion process for improving the adhesion between the wafer W and the resist liquid film, and a solvent remaining in the resist applied on the wafer W are heated and evaporated. A pre-baking mechanism 15 for performing the heating and a cooling mechanism 16 for cooling the heat-treated wafer W are arranged.
On the other side of the transfer path 11, a processing liquid coating mechanism 17 for coating a resist on the surface of the wafer W (the processing apparatus of the present invention).
In order to prevent diffuse reflection during the exposure process, the wafer W
And a surface coating layer coating mechanism 18 for coating and forming a CEL film or the like on the resist.

In the resist coating and developing apparatus configured as described above, first, the unprocessed wafer W is unloaded from the wafer carrier 2 by the arm 4 of the loading / unloading mechanism 1 and placed on the alignment stage 6. To be done. Then
The wafer W on the alignment stage 6 is transferred by the transfer mechanism 12
Is held by the main arm 13 of each of the processing mechanisms 14-1.
It is transported to 8. Then, the processed wafer W is returned to the alignment stage 6 by the main arm 13.
Further, it is transferred by the arm 4 and stored in the wafer carrier 3.

As shown in FIG. 2, the processing apparatus 17 of the present invention includes a spin chuck 21 as a rotation holding means for horizontally adsorbing and holding a semiconductor wafer W, which is a plate-shaped object, and horizontally rotating it. The processing liquid supply nozzle 22 that is moved onto the spin chuck 21 and supplies the resist liquid, which is a processing liquid, to the surface of the wafer W, and the spin chuck 21 are concentrically formed so as to surround the periphery below the wafer holding portion 21A of the spin chuck 21. An annular inner cup 29 arranged and an outer cup 30 which surrounds the spin chuck 21 and the inner cup 29 to prevent the processing liquid from scattering outside the apparatus, constitute a main part.

The inner cup 29 is formed from a bottom portion of the outer cup 30 to substantially surround the spin chuck 21 and a cylindrical standing portion 29a, and an upper end portion of the standing portion 29a. A horizontal portion 29b having the same outer diameter as the upper surface 31 of the wafer W and the same diameter as the wafer W, and a slanted portion 29c extending while being slanted downward from slightly inside the outer peripheral edge portion of the horizontal portion 29b, and this slant The outer peripheral portion of the portion 29c is configured to have an outer peripheral portion 29d that hangs from the outer peripheral portion of the portion 29c near the bottom portion of the outer cup 30. The inner cup 29 has a double inner / outer annular flow path (inner annular flow path 3) whose lower portion communicates with the inner peripheral portion of the outer cup 30.
5, the outer annular flow path 36) is defined. Further, the outer peripheral edge of the upper surface 31 of the horizontal portion 29b of the inner cup 29 has the wafer W
Is located at the same position as the edge of the wafer W so that the resist solution can be prevented from entering the back surface of the wafer W. The angle α of the inclined portion 29c with respect to the horizontal plane is α = 30
The angle is set to ° to 45 ° (see FIG. 4).

The outer cup 30 has a large opening at the top so that the wafer W can be taken in and out, and an exhaust port 32 and a drain port 33, which will be described later, are provided at the bottom part. Outer cup 30
The upper opening edge portion 30a is folded inward in a V-shaped or U-shaped cross section. The folding angle β of the upper opening edge portion 30a is set within a range of β = 45 ° to 60 ° (see FIG. 5). In addition, the standing portion 2 is provided on the bottom of the outer cup 30.
An annular partition member 34 that surrounds the lower part of the periphery of 9a is provided, and an intermediate annular flow passage 37 is formed between the inner annular flow passage 35 and the outer annular flow passage 36. And the inner annular flow path 3
An exhaust port 32 is opened inside 5, and a drain port 33 is opened near the outer annular flow path 36. The height of the partition member 34 is set to be slightly higher than the lower end portion of the outer peripheral portion 29d of the inner cup 29.

The distance between the inner peripheral wall of the outer cup 30 and the outer peripheral portion 29d of the inner cup 29 is smaller than the distance between the partition member 34 and the outer peripheral portion 29d of the inner cup 29 by a predetermined distance.
As a result, the flow passage area S1 of the outer annular flow passage 36 and the flow passage area S2 of the intermediate annular flow passage 37 are set equal (see FIG. 3).

The exhaust port 32 is provided with a cylindrical flow velocity interference section 42 having the same diameter as the exhaust port 32, and a pipe 38 having a diameter smaller than that of the exhaust port 32 is connected to the tip of the flow velocity interference unit 42. The flow velocity interfering portion 42 is provided to prevent the flow of the air A near the exhaust port 32 from becoming extremely stronger than the flow away from the exhaust port 32, and its length (depth) Is longer, the more effective is the averaging of the flow velocity. A damper 39 for adjusting the exhaust amount is provided in the middle of the pipe 38. The damper 39 is driven by a damper drive device (not shown) based on an exhaust flow rate detection value by an exhaust flow rate sensor 41, which is desirably attached to the inner space on the upper wall of the outer cup 30, to accurately control the exhaust flow rate. You can do this. The drainage port 33 is connected to a drainage storage tank (not shown) via a pipe 40.

In the resist coating apparatus according to the present invention having the above-mentioned structure, the outer cup 30 is opened from the exhaust port 32.
When the inside is evacuated, the air A introduced from the upper opening of the outer cup 30 is made to flow radially along the surface of the wafer W, and then descends between the inner cup 29 and the outer cup 30, The outer annular flow path 36, the intermediate annular flow path 37, and the inner annular flow path 35 flow in this order to reach the exhaust port 32, and the damper 39
Is exhausted through. Channel area S1 of the outer annular channel 36
Since the flow path area S2 of the intermediate annular flow path 37 is set to be equal to each other, the pressure loss between the inner and outer flow paths due to the difference in the flow path area is suppressed to a small level, and the exhaust gas imbalance due to the position of the exhaust port 32. Is reduced and the exhaust flow rate is made uniform over the entire area of the outer annular flow path 36. Further, since the flow velocity interference portion 22 is provided between the exhaust port 32 and the pipe, the flow of the air A can be satisfactorily generated even at a position away from the exhaust port 32. Therefore, the outer cup 3
It is possible to favorably convey and discharge the resist solution which has become a mist by hitting the inner wall of No. 0 by the flow of the air A to prevent the resist solution from flying to the surface of the wafer W and improve the uniformity of the coating film.

Further, since the damper 39 is driven based on the detected value of the exhaust flow rate by the exhaust flow rate sensor 21 and the exhaust flow rate is constantly controlled appropriately, turbulent flow occurs in the exhaust flow due to too strong exhaust. However, there is no inconvenience such as streamline unevenness or striation occurring in the resist film. Further, since the inclination angle α of the inclined portion 29c of the inner cup 29 is set to 30 ° to 45 °, the flow of the air A is rectified and the rear surface of the wafer W or the upper surface 31 of the inner cup 29 is rectified.
It is possible to prevent the resist solution from adhering to. Further, since the upper opening edge portion 30a of the outer cup 30 is folded back at the predetermined folding angle β as described above, the resist solution which has become a mist and hits the inner wall of the outer cup 30 along the inner wall. Even when the wafer W is raised, as shown in FIG. 5, the folded-back portion prevents the further movement of the folded-back portion and prevents the wafer W from scattering.

FIG. 6 is a schematic sectional view of a second embodiment of the present invention, and FIG. 7 is a sectional view of a main part of the second embodiment.

The processing apparatus in the second embodiment is a wafer W.
This is a case where it is possible to more reliably prevent the resist liquid from entering between the upper surface 31 of the inner cup 29 and the inner cup 29. That is, the outer peripheral edge portion 31 extending radially outward along the outer peripheral edge portion of the upper surface 31 of the inner cup 29 according to the diameter of the wafer W.
This is the case where a is formed. By forming in this way, the inclined portion 29c is provided slightly inside the outer peripheral edge portion of the horizontal portion 29b, and the upper outer peripheral edge portion 31a of the inner cup 29 extends radially outward in accordance with the diameter of the wafer W. Therefore, as shown in FIG. 7, the upper surface outer peripheral edge portion 31 from which the air A that tries to go around from the peripheral edge portion of the wafer W to the back surface side is extended.
It can be blocked on the back side of a. Therefore, it is possible to prevent the resist liquid from adhering to the back surface of the wafer W or the upper surface of the inner cup 29, and to prevent the generation of particles due to the resist that has adhered and dried.

Since the other parts of the second embodiment are the same as those of the first embodiment, the same parts are designated by the same reference numerals and the description thereof will be omitted.

In the above embodiment, the case where the plate-shaped object is a semiconductor wafer has been described, but the present invention is not limited to this. For example, the present invention is also applicable to the case where a processing liquid is similarly spin-coated on an LCD substrate or a printed circuit board. It is possible. Further, in the above embodiment, the case where the spin coater is applied to the resist coater has been described, but it is needless to say that the invention can be applied not only to the resist coater but also to, for example, an etching liquid coater or a device for performing a magnetic liquid coater. is there.

[0031]

As described above, according to the processing apparatus of the present invention, the following excellent effects can be obtained.

1) According to the processing apparatus of the first aspect, since the flow passage area of the outer annular flow passage and the flow passage area of the intermediate annular flow passage are set equal to each other, the pressure loss due to the difference in the flow passage area is reduced. It can be kept small, and good air flow can be generated even at a position away from the exhaust port. Therefore, the mist-like treatment liquid that hits the inner wall of the outer cup is satisfactorily conveyed and discharged by the air flow to prevent the treatment liquid from flying to the surface of the object to be treated and improve the uniformity of the coating film. Can be made

2) According to the processing apparatus of claim 2, since the outer peripheral edge portion of the upper surface of the inner cup is extended outward in the radial direction according to the diameter of the object to be processed, the peripheral edge portion of the object to be processed is It is possible to prevent the flow of air that tends to go around to the back surface side at the back surface of the extended outer peripheral edge portion. Therefore, it is possible to prevent the processing liquid from adhering to the back surface of the object to be processed and the upper surface of the inner cup, and to prevent the generation of particles.

[Brief description of drawings]

FIG. 1 is a schematic plan view showing an entire resist coating / developing apparatus having a processing apparatus of the present invention.

FIG. 2 is a sectional perspective view showing a first embodiment of the processing apparatus of the present invention.

FIG. 3 is a sectional view taken along line III-III in FIG.

FIG. 4 is an enlarged sectional view showing an inclined portion of the inner cup according to the present invention.

FIG. 5 is an enlarged cross-sectional view showing an upper opening portion of the outer cup according to the present invention.

FIG. 6 is a schematic sectional view showing a second embodiment of the processing apparatus of the present invention.

FIG. 7 is an enlarged sectional view showing an outer peripheral edge portion of the upper surface in the second embodiment.

FIG. 8 is a schematic vertical sectional view showing a conventional processing apparatus.

9 is an enlarged cross-sectional view showing an IX part in FIG.

[Explanation of symbols]

 21 spin chuck (rotating and holding means) 29 inner cup 29a standing portion 29d outer peripheral portion 30 outer cup 31a upper surface outer peripheral edge portion 32 exhaust port 34 partition member 35 inner annular flow passage 36 outer annular flow passage 37 intermediate annular flow passage S1 outer annular flow Passage area of the passage S2 Passage area of the intermediate annular passage W Wafer (Plate shaped object)

Claims (2)

[Claims] 1. A rotation holding means for holding and rotating an object to be processed, an outer cup surrounding the rotation holding means, and an outer cup for surrounding the lower part of the object holding portion of the rotation holding means. An inner cup standing upright from the bottom, and an exhaust port opening to the inner annular channel of the inner-outer double annular channel partitioned by the partition member standing upright on the bottom of the outer cup, and the upper part of the inner cup A process characterized in that the annular flow path is divided into an outer side and an intermediate annular flow path by an outer peripheral portion that hangs from the outer circumference, and the flow path areas of the outer annular flow path and the intermediate annular flow path are set equal to each other. apparatus. 2. A processing apparatus comprising: a rotation holding means for holding and rotating an object to be processed; and an annular inner cup surrounding a lower part of the object to be processed holding portion of the rotation holding means. A processing apparatus, wherein an outer peripheral edge portion is formed on the outer peripheral edge portion of the upper surface and extends outward in the radial direction according to the diameter of the object to be processed.