JP2580082B2 - Substrate rotation processing equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for forming a thin film of a processing solution on a substrate surface, such as a pre-wet process in which a thin film of pure water or a diluted developing solution is formed on the substrate surface before the development process of the substrate. The present invention relates to a substrate rotation processing apparatus used in the process.

[0002]

2. Description of the Related Art In a substrate developing process, a thin film of pure water or a diluted developing solution is previously formed on a substrate surface to supply a developing solution to a rotating substrate, so that the substrate surface is wet. Pre-wet treatment is considered to be effective in performing uniform development.
As shown in Japanese Patent No. 39540, a processing liquid for surface wetting (referred to as a rinsing liquid in the publication) is supplied to the vicinity of the center of a rotating substrate to diffuse and flow, thereby forming a thin film of the processing liquid on the substrate surface. Means for forming have been proposed.

[0003]

However, the above-mentioned conventional apparatus is configured to supply the processing liquid for surface wetting to the vicinity of the center of the substrate by using a single nozzle. There is a point. That is, in a rotating substrate, the peripheral speed increases as going from the substrate center to the substrate outer periphery. Therefore, the supplied processing liquid tends to be less likely to be scattered and to remain at the center of the substrate than to the outer peripheral part, and conversely the processing liquid tends to be scattered and dried at the outer peripheral part of the substrate by centrifugal force. As described above, since there is a difference in the tendency of the diffusion and flow of the processing liquid between the inside and the outside of the substrate, if the substrate rotation processing time is increased in order to generate a uniform thin film at the center of the substrate, the processing is performed at the outer peripheral portion of the substrate. The liquid dries. On the other hand, if the substrate rotation processing time is shortened in order to generate a uniform thin film
There is a disadvantage that an excessive processing solution remains in the center of the substrate. Thus, according to the conventional apparatus, it was difficult to form a uniform thin film on the entire surface of the substrate.

The present invention has been made in view of such circumstances, and has as its object to provide a substrate rotation processing apparatus capable of forming a uniform thin film of a processing liquid on a substrate surface.

[0005]

In order to achieve the above object, the present invention has the following arrangement. In other words, the present invention provides a substrate rotation processing apparatus that ejects and supplies a processing liquid toward the surface of a substrate that is mounted and held on a rotating table and rotates to form a thin film of the processing liquid on the substrate surface. Using a nozzle heading near the center and a nozzle heading away from the center of rotation on the outer periphery side, the processing liquid is ejected and supplied to a plurality of different locations on the substrate surface in the radial direction, and the nozzle on the rotation center side And a processing liquid supply control means for stopping the supply of the processing liquid in order.

[0006]

The operation of the present invention is as follows. By stopping the supply of the processing liquid in order from the nozzle on the rotation center side,
The supply time of the processing liquid is relatively short in the central portion of the substrate where the processing liquid is likely to remain, while the supply time of the processing liquid is relatively long in the outer peripheral portion of the substrate where the processing liquid is easily scattered. That is, as a result of supplying the processing liquid in an amount corresponding to the peripheral speed of each part of the substrate, a uniform thin film of the processing liquid is formed on the entire substrate.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a substrate rotation processing apparatus according to the present invention will be described below with reference to the drawings. FIG. 1 is a longitudinal sectional view of a substrate rotation processing apparatus according to the present embodiment, in particular, an apparatus for performing a pre-wet processing and a development processing on a substrate after photoresist coating and exposure. A substrate 1 such as a semiconductor wafer to be processed is mounted and held on a rotary table 2 of a vacuum chuck type that is driven to rotate about a vertical axis P. Above the turntable 2, a developer supply nozzle 3 that can be moved up and down
The periphery of the turntable 2 is surrounded by a guard housing 4.

Outside the guard housing 4, there are two nozzles 5 and 6 for supplying a pre-wet processing liquid. The direction of the lower nozzle 5 is set so that the processing liquid jetted into the guard housing 4 through the opening 7 formed in the guard housing 4 hits the vicinity of the vertical axis P which is the rotation center of the substrate 1. Have been. Here, the vicinity of the vertical axis P means not necessarily limited to the center of rotation. In the case of an 8-inch semiconductor wafer, it is preferably about 5 mm away from the center. However, the optimum distance from the center varies somewhat depending on the discharge pressure and flow rate of the processing liquid and the direction thereof, and thus cannot be specified unconditionally. In short, the region of the processing liquid ejected from the nozzle 5 and spread on the surface of the substrate 1 only needs to include the rotation center. On the other hand, the injection direction of the upper nozzle 6 is set so as to be directed to a position radially outwardly distant from the nozzle 5.
More specifically, the direction of the nozzle 6 is set so that the processing liquid ejected from the nozzle 6 hits near the center between the rotation center and the periphery of the substrate (about 50 mm from the center in the case of an 8-inch wafer).

As shown in FIG. 3, the nozzles 5 and 6 are respectively connected to the processing liquid pressure feeding device 10 through electromagnetic on-off valves 8 and 9.
In addition, each of the electromagnetic on-off valves 8 and 9 is controlled to be opened and closed by a control circuit 11 as processing liquid supply control means. Note that filters 12 are interposed between the electromagnetic on-off valves 8 and 9 and the nozzles 5 and 6, respectively, to remove foreign substances in the processing liquid.

The pre-wet processing using the nozzles 5 and 6 is performed as follows. Before performing the developing process, the electromagnetic on / off valves 8 and 9 are simultaneously opened to supply pure water (or a diluted developing solution) as a pre-wet processing solution to the surface of the substrate 1 from the nozzles 5 and 6. . At this time, the substrate 1 is 5
It is rotated at 00 to 1000 revolutions / minute. The supply time of the processing liquid is about 5 seconds. Then, under the control of the control circuit 11, the supply of the processing liquid from the nozzle 5 is first stopped, and then the supply of the processing liquid from the nozzle 6 is stopped with a delay of 0.5 to 1 second. However, the optimal stop timing of the supply of the processing liquid from the nozzles 5 and 6 differs depending on the size and the number of rotations of the substrate 1 and the type of the processing liquid. After the supply of the processing liquid from both nozzles 5 and 6 is stopped,
The excess processing liquid is scattered by being rotated at about 0 to 2000 rotations / minute for about 2 seconds to form a uniform thin film of the processing liquid on the surface of the substrate 1. After the above pre-wet processing is completed, the developing liquid supply nozzle 3 is lowered to supply the developing liquid, and the rotary developing processing of the substrate is performed.

In the above embodiment, two nozzles for supplying the processing liquid are used. However, three or more nozzles may be used depending on the size of the substrate 1. In this case, the center of the substrate is also used. The supply of the processing liquid is controlled to be stopped in order from the side toward the side. Further, in the embodiments, the pre-wet processing is described as an example, but the present invention is not limited to this, and can be applied to various kinds of processing in which a thin film of a processing liquid needs to be uniformly formed on a substrate. it can.

[0012]

As is apparent from the above description, according to the present invention, the processing liquid is jetted and supplied to a plurality of different positions in the radial direction of the rotating substrate, and the stop of the processing liquid supply is performed on the center side. From the outer peripheral side, so that the processing liquid is prevented from remaining in the central part of the substrate having a low peripheral velocity, and the processing liquid is prevented from being excessively scattered in the peripheral part of the substrate having a high peripheral velocity, As a result, a thin film of the processing liquid can be uniformly formed on the entire surface of the substrate.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing one embodiment of a substrate rotation processing apparatus according to the present invention.

FIG. 2 is a perspective view of a main part of the embodiment.

FIG. 3 is a block diagram illustrating a configuration of a processing liquid supply unit.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Substrate 2 ... Rotary table 5, 6 ... Nozzle 11 ... Control circuit (processing liquid supply control means)

Claims (1)

(57) [Claims] 1. A substrate rotation processing apparatus for ejecting and supplying a processing liquid toward a surface of a substrate mounted and held on a rotating table and rotating to form a thin film of the processing liquid on the substrate surface. Using a nozzle directed to the vicinity and a nozzle directed to a position distant from the rotation center to the outer peripheral side, the processing liquid is ejected and supplied to a plurality of different positions in the radial direction of the substrate surface, and from the nozzle on the rotation center side A substrate rotation processing apparatus comprising processing liquid supply control means for sequentially stopping the processing liquid supply.