JPH11238667A - Processing liquid coating device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a processing liquid coating device, wherein a resist is adequately prevented from creeping into the rear surface of a semiconductor wafer through a simple configuration, strengthening the air current heating for an outer periphery side from a rotation center side, on a rear surface side of the semiconductor wafer. SOLUTION: A spin chuck 3 rotated by a motor 4 is provided inside an annular cup 2, and a semiconductor wafer 5 is held by the spin chuck 3 for rotation, so that the surface of the semiconductor wafer 5 is coated with a resist, while a resist splashed from the outer periphery of the semiconductor wafer 5 through rotation is housed from an annular opening 2d formed at the annular cup 2. A fan 6 is provided on the rear surface side of the spin chuck 3, and at rotation of the spin chuck 3, the air current heading for the outer periphery side from rotation center side is formed on the rear surface side of the semiconductor wafer 5.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a processing liquid coating apparatus which can be used, for example, for coating a resist on the surface of a semiconductor wafer.

[0002]

2. Description of the Related Art Japanese Patent Application Laid-Open No. Hei 8-97134 discloses a coating apparatus in which the resist is prevented from solidifying in an annular cup for collecting the resist scattered from a semiconductor wafer, thereby improving maintainability. Is disclosed.
Describing the basic configuration of this coating apparatus, a spin chuck is provided inside an annular cup, and a semiconductor wafer is held and rotated by the spin chuck to apply a resist on the surface of the semiconductor wafer. Then, the resist scattered from the outer periphery of the semiconductor wafer by rotation is accommodated through an annular opening formed in the annular cup, and the accommodated processing liquid is discharged from a discharge pipe connected to the bottom of the annular cup. I have. Further, the coating apparatus is configured to generate a downflow from above the annular cup to below. This downflow extends from the outside of the annular cup through the bottom to the inside of the annular cup, and from the rotation center side to the outer periphery side on the back side of the semiconductor wafer held by the spin chuck provided inside the annular cup. Creates an oncoming airflow. This airflow prevents the resist from going around the back surface of the semiconductor wafer. The airflow enters the inner space of the annular cup from an annular opening formed in the annular cup, and is discharged through a discharge pipe connected to the bottom of the annular cup. The resist scattered from the outer periphery of the semiconductor wafer is guided to the discharge pipe by the airflow formed in the inner space of the annular cup.

[0003]

However, in the above-mentioned conventional configuration, a dedicated large fan motor for generating a downflow from the upper side to the lower side of the annular cup is required. This leads to complexity and cost. Furthermore, it is difficult to obtain a sufficiently strong airflow from the center of rotation toward the outer periphery on the back side of the semiconductor wafer. The same applies to the airflow that enters the annular opening and reaches the discharge pipe. For this reason, it is not possible to sufficiently prevent the resist from wrapping around the back surface of the semiconductor wafer, and it is not possible to sufficiently prevent the resist scattered from the semiconductor wafer from adhering to the inside of the annular cup.

In view of the above circumstances, the present invention can increase the airflow from the center of rotation to the outer periphery on the back side of the semiconductor wafer with a simple configuration, and is formed on the annular cup. It is an object of the present invention to provide a processing liquid application device capable of increasing the airflow from an annular opening to a discharge pipe.

[0005]

According to the present invention, there is provided a treatment liquid coating apparatus, wherein a spin chuck rotated by a rotation driving means is provided inside an annular cup to solve the above-mentioned problems.
The processing liquid is applied to the surface of the substrate to be coated by holding and rotating the substrate to be coated by the spin chuck, and the processing liquid scattered from the outer periphery of the substrate to be rotated by rotation is formed in the annular cup. In the processing liquid coating apparatus configured to be accommodated from the annular opening, a fan rotated by the rotation driving unit is provided inside the annular cup, and when the spin chuck is rotated, the back side of the substrate to be coated is rotated from the rotation center side to the outer circumference side. Characterized by forming an airflow toward

With the above arrangement, the airflow from the center of rotation to the outer periphery on the back side of the substrate to be coated is directly formed inside the annular cup by the fan provided inside the annular cup. Therefore, it becomes stronger as compared with the case where the conventional downflow is adopted. The fan is driven by a rotary drive unit for rotating the spin chuck, and there is no need to provide a separate dedicated rotary drive unit. Therefore, it is possible to reduce the size of the apparatus, simplify the structure, and reduce the cost. it can.

Further, in the treatment liquid coating apparatus of the present invention, a spin chuck rotated by a rotation driving means is provided inside the annular cup, and the substrate to be coated is held and rotated by the spin chuck to rotate the substrate. The treatment liquid was applied to the surface of the substrate, and the treatment liquid scattered from the outer periphery of the substrate to be applied by rotation was accommodated through an annular opening formed in the annular cup, and the accommodated treatment liquid was connected to the bottom of the annular cup. In a processing liquid application device configured to be discharged from a discharge path, a fan rotated by the rotation driving unit is provided in the discharge path, and an airflow from the annular opening toward the discharge path is formed when the spin chuck rotates. It is characterized by having comprised in.

With the above configuration, the airflow from the annular opening toward the discharge passage is formed directly in the discharge passage by the fan provided in the discharge passage.
This is stronger than when a conventional downflow is adopted. The fan is driven by a rotation drive unit for rotating the spin chuck, and it is not necessary to provide a separate dedicated rotation drive unit. Therefore, the size, the structure, and the cost of the device are reduced. Can be.

[0009] The apparatus may further comprise a rotation speed control means for controlling the rotation speed of the rotation speed driving means. Accordingly, for example, the driving unit can be rotated at a rotation speed suitable for applying the processing liquid to the substrate to be applied and capable of obtaining an airflow having a desired strength. Note that such a rotational speed can be determined experimentally.

[0010]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a schematic configuration diagram showing a treatment liquid coating apparatus 1 according to this embodiment.

The annular cup 2 has an outer peripheral wall surface 2a, an inner peripheral wall surface 2b, and a bottom surface 2c. An annular space is formed by the two wall surfaces 2a and 2b and the bottom surface 2c. The upper edge of the outer peripheral wall 2a is located above the upper edge of the inner peripheral wall 2b, and the gap formed between the upper edges is the annular opening 2.
d. A spin chuck 3 is provided inside the annular cup 2. The spin chuck 3 is fixed to a rotating shaft 4a of a motor 4, and rotates by rotating the rotating shaft 4a. Further, a vacuum means (not shown) is connected to the spin chuck 3. The semiconductor wafer (substrate to be coated) 5 placed on the upper surface of the spin chuck 3 is sucked by the vacuum means and fixed on the upper surface of the spin chuck 3.

On the back surface of the spin chuck 3, a first fan 6 is provided. The first fan 6 has a plurality of blades, rotates together with the spin chuck 3, and
On the back side of the semiconductor wafer 5, an airflow from the center of rotation toward the outer periphery is formed. The plate member 7 provided below the first fan 6 has a through hole 7a. A peripheral wall plate 8 that covers the periphery of the motor 4 is provided below the plate member 7.
Thus, the through hole 7a is isolated from the housing space for housing the motor 4. Further, a gap is formed between the bottom surface 2c of the annular cup 2 and the base 9, and a space for accommodating the first fan 6 is provided in the annular cup 2 through the through hole 7a and the gap. It communicates with the outside space.

A plurality of discharge pipes 10 for discharging the resist housed from the annular opening 2d are connected to the bottom surface 2c of the annular cup 2. These discharge pipes 10
They merge in the junction chamber 11 and are connected to one discharge pipe 12. The merging chamber 11 is provided with a second fan 13. The second fan 13 is fixed to a rotating shaft 4a of the motor 4, and rotates as the rotating shaft 4a rotates to form an airflow from the annular opening 2d toward the discharge pipe 10.

A motor 4 for rotating the spin chuck 3
Is connected to a rotation speed control unit 14 for controlling the rotation speed.

Next, the contents of processing when applying a resist and the contents of operation of the processing liquid coating apparatus 1 will be described below.
First, the semiconductor wafer 5 is fixed on the spin chuck 3 by placing the semiconductor wafer 5 on the spin chuck 3 and operating a vacuum means (not shown). And
A resist is dropped on the semiconductor wafer 5 from a resist nozzle (not shown) provided above the annular cup 2, and the motor 4 is operated to rotate the spin chuck 3. The resist is applied on the surface of the semiconductor wafer 5 by the centrifugal force of this rotation, and the resist scattered from the outer periphery of the semiconductor wafer 5 is accommodated in the annular space of the annular cup 2 from the annular opening 2d.

The rotation of the motor 4 causes the first fan 6 to rotate.
Is rotated, air outside the annular cup 2 enters the inside of the annular cup 2 through a gap between the bottom surface 2c of the annular cup 2 and the base 9, but the peripheral wall plate 8 is provided. As a result, without absorbing the heat of the motor 4, it passes through the through hole 7 a and enters the housing space of the first fan 6, and the upper edge of the inner peripheral wall surface 2 b and the outer peripheral edge of the semiconductor wafer 5 Get out of the gap between. As a result, an airflow is formed on the back surface of the semiconductor wafer 5 from the center of rotation to the outer periphery.

When the second fan 13 rotates by the rotation of the motor 4, the air in the discharge pipe 10 is sucked and sent to the discharge pipe 12, so that the air passes through the annular space of the annular cup 2 from the annular opening 2d. Thus, an airflow toward the discharge pipe 10 is generated. The scattered resist entering from the annular opening 2d by this air flow reaches the discharge pipe 10 without remaining in the annular space of the annular cup 2, and is further guided to a discharge end (not shown) through the discharge pipe 12.

As described above, on the back side of the semiconductor wafer 5, the airflow from the rotation center side to the outer side is directly generated inside the annular cup 2 by the first fan 6 provided on the back side of the spin chuck 3. Therefore, the resist on the semiconductor wafer 5 can be sufficiently prevented from wrapping around to the back surface side because the resist is stronger than when a conventional downflow is adopted. Further, due to the airflow and the strong airflow from the annular opening 2d formed by the second fan 13 toward the discharge pipe 10, the scattered resist stored in the annular cup 2 from the annular opening 2d is strongly discharged to the discharge pipe 10. Will be led,
It is possible to prevent the scattering resist from adhering and solidifying in the annular cup 2. The first fan 6 and the second fan 13 are driven to rotate by the motor 4 for rotating the spin chuck 3, and there is no need to provide a separate dedicated rotation driving means. Simplification and cost reduction can be achieved. Also,
By providing the rotation speed control unit 14, for example, the motor 4 is rotated by setting a rotation speed suitable for applying a resist to the semiconductor wafer 5 and capable of obtaining an airflow having a desired strength. It is possible to do.

In this embodiment, the structure in which the first fan 6 is provided on the spin chuck 3 is employed. However, the present invention is not limited to this, and a structure in which the first fan 6 is fixed to the rotating shaft 4a of the motor 4 may be employed. Things. Further, the fans 6 and 13 may obtain the driving force of the motor 4 via a transmission mechanism such as a gear.

[0020]

As described above, according to the present invention, it is possible to prevent the processing liquid from flowing to the back surface of the substrate to be coated while reducing the size of the apparatus, simplifying the structure and reducing the cost. This has the effect of preventing the scattering resist from adhering and solidifying in the annular cup.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram showing a treatment liquid application device according to an embodiment of the present invention.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 treatment liquid coating device 2 annular cup 3 spin chuck 4 motor 5 semiconductor wafer (substrate to be coated) 6 first fan 10 discharge pipe 11 merging chamber 12 discharge pipe 13 second fan 14 rotation speed control unit

Claims (3)

[Claims] A spin chuck rotated by a rotation driving means is provided inside an annular cup, and a processing liquid is coated on a surface of the substrate by holding and rotating the substrate by the spin chuck. In addition, in a processing liquid coating apparatus configured to receive a processing liquid scattered from the outer periphery of the substrate to be coated by rotation through an annular opening formed in the annular cup, a fan rotated by the rotation driving unit is rotated by the annular cup. Wherein the spin chuck is rotated to form an airflow from the center of rotation toward the outer periphery on the back side of the substrate to be coated when the spin chuck is rotated. 2. A spin chuck rotated by a rotation driving means is provided inside an annular cup, and a processing liquid is coated on the surface of the substrate by holding and rotating the substrate by the spin chuck. At the same time, the processing liquid scattered from the outer periphery of the substrate to be applied by rotation is accommodated from an annular opening formed in the annular cup, and the accommodated processing liquid is discharged from a discharge path connected to the bottom of the annular cup. In the liquid coating apparatus, a fan rotated by the rotation driving unit is provided in the discharge path, and the air flow is formed from the annular opening toward the discharge path when the spin chuck rotates. Liquid coating device. 3. The processing liquid application apparatus according to claim 1, further comprising a rotation speed control unit that controls a rotation speed of the rotation driving unit.