JPH04307724A - Rotary treatment apparatus of substrate - Google Patents

Abstract

PURPOSE:To uniformly form thin film of a treatment liquid on the surface of a substrate which is turning. CONSTITUTION:A treatment liquid is spouted and supplied to a plurality of different parts in the radial direction on the surface of a substrate 1 by using the following: a nozzle 5 which is directed to a part near the center of rotation of the substrate 1; and a nozzle 6 which is directed to a part toward the outer circumferential side separating from the center of rotation. The supply of the treatment liquid is stopped sequentially from the nozzle on the side of the center of rotation. Thereby, it is possible to prevent the excess treatment liquid from being left in the central part of the substrate 1, whose circumferential speed is slow, and it is possible to restrain the treatment liquid from being sprayed excessively at the outer circumferential side of the substrate 1, whose circumferential speed is fast, so that it is possible to uniformly form the thin film of the treatment liquid on the whole surface of the substrate 1.

Description

[Detailed description of the invention]

0001

[Industrial Application Field] The present invention is applicable to forming a thin film of processing liquid on the surface of a substrate, such as in pre-wet processing, in which a thin film of pure water or diluted developer is formed on the surface of the substrate before the development processing of the substrate. The present invention relates to a substrate rotation processing apparatus used in processing.

0002

2. Description of the Related Art In substrate development processing, a thin film of pure water or diluted developer is previously formed on the substrate surface to make the substrate surface wet before the developer is supplied to the rotating substrate. Pre-wet processing is said to be effective in achieving uniform development; for example, in JP-A-56-
As shown in Publication No. 39540, a thin film of the treatment liquid is formed on the surface of the substrate by supplying a surface wetting treatment liquid (referred to as a rinsing liquid in the publication) near the center of a rotating substrate and causing it to diffuse and flow. A means of forming the

0003

[Problems to be Solved by the Invention] However, the above-mentioned conventional apparatus is configured to supply a treatment liquid for surface wetting near the center of the substrate using a single nozzle, and therefore has the following problems. There is a point. That is, in a rotating substrate, the circumferential speed increases from the center of the substrate to the outer periphery of the substrate. Therefore, the supplied processing liquid tends to be less likely to scatter and remain at the center of the substrate than at the outer periphery, and conversely, the processing liquid tends to scatter due to centrifugal force and dry easily at the outer periphery of the substrate. In this way, there is a difference in the tendency of diffusion and flow of the processing liquid between the inside and outside of the substrate, so if the substrate rotation processing time is increased in order to generate a uniform thin film at the center of the substrate, the processing at the outer periphery of the substrate will be The liquid becomes dry. On the other hand, if the substrate rotation processing time is shortened in order to generate a uniform thin film on the outer periphery of the substrate, an inconvenience arises in that an excessive amount of processing liquid remains at the center of the substrate. As described above, with the conventional apparatus, it is difficult to generate a uniform thin film over the entire surface of the substrate.

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

[0005]

[Means for Solving the Problems] In order to achieve the above object, the present invention has the following configuration. That is, the present invention provides a substrate rotation processing apparatus that sprays and supplies a processing liquid toward the surface of a rotating substrate mounted and held on a rotating table to form a thin film of the processing liquid on the substrate surface. A nozzle directed toward the center and a nozzle directed toward a location away from the center of rotation toward the outer periphery are used to spray and supply processing liquid to multiple locations in the radial direction of the substrate surface. The apparatus is equipped with a processing liquid supply control means for sequentially stopping the processing liquid supply.

[0006]

[Function] The function of the present invention is as follows. By stopping the supply of processing liquid sequentially from the nozzle on the rotation center side,
The processing liquid supply time is relatively short at the center of the substrate where the processing liquid tends to remain, while the processing liquid supply time is relatively long at the outer periphery of the substrate where the processing liquid tends to scatter. That is, as a result of supplying the processing liquid in an amount corresponding to the circumferential speed of each part of the substrate, a uniform thin film of the processing liquid is formed over the entire substrate.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the 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, particularly an apparatus for performing prewet processing and development processing on a substrate that has been coated with photoresist and exposed to light. A substrate 1 such as a semiconductor wafer to be processed is mounted and held on a vacuum chuck type rotary table 2 that is rotated around a vertical axis P. Above the rotary table 2 is a developer supply nozzle 3 that can be raised and lowered.
The rotary table 2 is surrounded by a guard housing 4.

There are two nozzles 5 and 6 on the outside of the guard housing 4 for supplying a prewetting treatment liquid. The direction of the lower nozzle 5 is set so that the processing liquid spouted into the guard housing 4 through the opening 7 formed in the guard housing 4 hits near the vertical axis P, which is the center of rotation of the substrate 1. has been done. Here, the vertical axis center P
Nearby 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, flow rate, and direction of the processing liquid, so it cannot be determined unconditionally. in short,
It is sufficient that the region of the processing liquid ejected from the nozzle 5 and spread over the surface of the substrate 1 includes the center of rotation. On the other hand, the injection direction of the upper nozzle 6 is set so that it is directed toward a location further away from the nozzle 5 in the radial direction. Specifically, the direction of the nozzle 6 is set so that the processing liquid ejected from the nozzle 6 hits near the midpoint between the center of rotation and the periphery of the substrate (approximately 50 mm from the center in the case of an 8-inch wafer).

As shown in FIG. 3, both nozzles 5 and 6 are connected to a processing liquid pressure feeding device 10 via electromagnetic on-off valves 8 and 9, respectively.
The electromagnetic opening/closing valves 8 and 9 are connected via piping to the opening/closing 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 from the processing liquid.

Prewet processing using the nozzles 5 and 6 is performed as follows. Before performing the development process, the electromagnetic on-off valves 8 and 9 are opened simultaneously to supply pure water (or diluted developer) as a pre-wetting process liquid to the surface of the substrate 1 from the nozzles 5 and 6. . At this time, the substrate 1 has 50
It is rotated at 0 to 1000 revolutions/minute. The processing liquid supply time is approximately 5 seconds. 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 timing for stopping the supply of the processing liquid from the nozzles 5 and 6 differs depending on the size and rotation speed of the substrate 1, as well as the type of processing liquid. Both nozzles 5,
After stopping the supply of the processing liquid from 6, the substrate 1 is placed at 700~
The substrate 1 is rotated at 2,000 rpm for about 2 seconds to scatter excess processing liquid and form a uniform thin film of the processing liquid on the surface of the substrate 1. After the above pre-wet process is completed, the developer supply nozzle 3 is lowered to supply a developer, and the substrate is subjected to a rotational development process.

[0011] In the above embodiment, two nozzles are used for supplying the processing liquid, but depending on the dimensions of the substrate 1, three or more nozzles may be used. The supply of processing liquid is controlled to be stopped in order from the side. Further, although the embodiments have been described using pre-wet processing as an example, the present invention is not limited to this, and can be applied to various types of processing that require uniform formation of a thin film of processing liquid on a substrate. can.

0012

Effects of the Invention As is clear from the above description, the present invention provides a method for spraying and supplying a processing liquid to a plurality of different radial locations on a rotating substrate, and for stopping the supply of the processing liquid to a center side. By sequentially delaying the process liquid from the center to the outer circumference, it is possible to prevent the processing liquid from remaining at the center of the substrate where the circumferential speed is slow, and to suppress excessive scattering of the processing liquid at the outer circumference of the substrate where the circumferential speed is high. As a result, a thin film of the processing liquid can be uniformly formed over the entire surface of the substrate.

[Brief explanation of drawings]

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

FIG. 2 is a perspective view of essential parts of the embodiment.

FIG. 3 is a block diagram showing the configuration of a processing liquid supply means.

[Explanation of symbols]

1...Substrate 2... Rotating table 5, 6...nozzle

Claims (1)

[Claims] 1. In a substrate rotation processing apparatus that sprays and supplies processing liquid toward the surface of a rotating substrate mounted and held on a rotating table to form a thin film of processing liquid on the substrate surface, the rotation center of the substrate is The processing liquid is sprayed and supplied to multiple locations in the radial direction of the substrate surface using a nozzle directed toward the vicinity and a nozzle directed toward a location away from the center of rotation toward the outer periphery. 1. A rotational processing apparatus for a substrate, comprising processing liquid supply control means for sequentially stopping supply of processing liquid.