JPH09232270A - Apparatus for cleaning treatment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a cleaning treatment apparatus which eliminates the need of the mixing operation of pure water with a chemical liquid by a method wherein the chemical liquid in a chemical-liquid tank is pressurized so as to be supplied to a pure-water supply,pipe and a cleaning liquid in which the chemical liquid is mixed with the pure water in a prescribed ratio is prepared. SOLUTION: A chemical liquid P in a chemical-liquid tank 57 is pressurized by nitrogen at a prescribed pressure so as to flow out to a chemical-liquid supply pipe 56, its flow rate is controlled by a flow-rate regulating valve 59, and the chemical liquid is made to flow into a pure-water supply pipe 52. At this time, when pure water which flows in the pure-water supply pipe 52 and the chemical liquid P which flows in the chemical-liquid supply pipe 56 are set to prescribed pressures, a cleaning liquid L in which the pure water and the chemical liquid P are mixed in a prescribed ratio can be supplied to a nozzle hole 32a and to an upper-part nozzle 37 without performing a mixing operation. In addition, since the chemical liquid P is pressurized so as to be mixed in the pure-water supply pipe 52, the chemical-liquid tank 57 can be made sufficiently small as compared with a conventional mixing tank which stores a cleaning liquid L which is mixed in advance.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cleaning processing apparatus for cleaning an object to be cleaned such as a semiconductor wafer and a glass substrate for liquid crystal one by one with a cleaning liquid ejected from a cleaning nozzle.

[0002]

2. Description of the Related Art In the manufacturing process of semiconductor devices, liquid crystal display devices, etc., there is a lithographic process for forming a circuit pattern on a semiconductor wafer or glass substrate as an object to be cleaned. In the lithography process, as is well known, a resist is applied to the semiconductor wafer, and the resist is irradiated with light through a mask on which a circuit pattern is formed, and then a portion of the resist which is not irradiated (or irradiated with light). The circuit pattern is formed by repeating a series of steps of removing the removed portion) and treating the removed portion several tens of times.

In each process, if the semiconductor wafer is contaminated, the circuit pattern cannot be precisely formed, which causes defective products. Therefore, when the circuit pattern is formed in each process, the semiconductor wafer is cleaned in a clean state where no resist or dust remains.

[0004] As the apparatus for cleaning the object to be cleaned, there are a batch type in which a plurality of semiconductor wafers are immersed in a cleaning tank containing a cleaning liquid for cleaning, and a method for rotating one object to be cleaned, and There is a single-wafer type in which a cleaning liquid is sprayed on an object to perform cleaning, and a single-wafer type having a high cleaning effect tends to be used as an object to be cleaned becomes larger.

There is a spin cleaning processing apparatus in the single-wafer cleaning processing apparatus. In order to further enhance the cleaning effect in this spin cleaning processing apparatus, a pure cleaning liquid is sprayed from the cleaning nozzle toward the object to be cleaned. A mixture of water and an acid or alkaline chemical is used.

When using a cleaning liquid prepared by mixing a chemical liquid with pure water, conventionally, a cleaning liquid is prepared by mixing the chemical liquid with pure water in a mixing tank at a predetermined concentration, and a cleaning nozzle is connected to the mixing tank via a pump. Then, the cleaning liquid in the preparation tank is sprayed from the cleaning nozzle toward the object to be cleaned.

However, when the cleaning liquid is supplied to the cleaning nozzle in this way, it involves a work of mixing the chemical liquid with a predetermined ratio of pure water, which requires a lot of trouble. Not only there,
There has been a case where the degree of mixing varies depending on the operator, which causes the cleaning ability of the cleaning liquid to be poor.

Further, when the cleaning liquid is supplied from the preparation tank, a preparation tank having a large volume must be prepared.
Although the mixing work must be performed frequently, it may be difficult to secure the installation space when using a large-volume mixing tank.

[0009]

As described above, conventionally, since the cleaning liquid prepared by previously mixing the chemical liquid with the pure water at the predetermined ratio is used, the mixing work is troublesome and the mixing degree is not constant. In addition, in order to secure a predetermined amount of the premixed cleaning liquid, it is necessary to increase the volume of the tank that stores the cleaning liquid, which makes it difficult to secure the installation location.

The present invention has been made based on the above circumstances, and an object thereof is to make it possible to supply a cleaning liquid in which a chemical liquid is mixed at a predetermined ratio with pure water without requiring a mixing operation. It is to provide a cleaning processing apparatus.

[0011]

According to a first aspect of the present invention, there is provided a cleaning treatment apparatus for cleaning an object to be cleaned by ejecting a cleaning liquid, which is a mixture of a chemical liquid and pure water, from a cleaning nozzle, which is connected to the cleaning nozzle. A pure water supply pipe for supplying the pure water at a predetermined pressure, a chemical liquid tank containing the chemical liquid, a chemical liquid supply pipe having one end connected to the chemical liquid tank and the other end connected to the cleaning nozzle, It has a pressurizing pipe having one end connected to the chemical liquid tank and a pressurized gas for pressurizing the chemical liquid in the chemical liquid tank supplied from the other end.

According to a second aspect of the invention, in the first aspect of the invention, an adjusting means for adjusting the flow rate of the chemical liquid flowing through the chemical liquid supply pipe is provided in the middle of the chemical liquid supply pipe. To do.

According to a third aspect of the present invention, in the first or second aspect of the present invention, at one end of the chemical liquid supply pipe, the chemical liquid pressure-fed by the pressurized gas into the chemical liquid supply pipe comes out from the one end. It is characterized in that a check valve for preventing the above is provided.

According to the first aspect of the present invention, the chemical liquid contained in the chemical liquid tank is pressurized and supplied to the pure water supply pipe through which pure water flows, so that the pure water is mixed with the chemical liquid at a predetermined ratio to form a cleaning liquid. Therefore, the mixing operation of mixing the chemical liquid with pure water is unnecessary, and the chemical liquid tank for storing the chemical liquid can be made sufficiently smaller than the tank for storing the pre-mixed cleaning liquid, and the installation thereof becomes easy.

According to the second aspect of the present invention, by controlling the flow rate of the chemical liquid flowing through the chemical liquid supply pipe, the cleaning ability of the cleaning liquid can be controlled according to the type of chemical liquid and the degree of contamination of the object to be cleaned.

According to the invention of claim 3, even if the end portion of the chemical liquid supply pipe is pulled out from the chemical liquid tank, the check valve provided at the end portion prevents air from entering the chemical liquid supply pipe. When replacing and using the chemical solution tank, it is not necessary to vent the chemical solution supply pipe.

[0017]

An embodiment of the present invention will be described below with reference to the drawings. The cleaning processing apparatus of the embodiment of the present invention shown in FIG. 2 includes a processing container 1. The upper surface of this processing container 1 is open, and the peripheral wall is inclined inward in the radial direction as the upper part moves toward the upper end.

At the bottom of the processing container 1, one end of a plurality of discharge pipes 2 is connected to the peripheral portion, and an insertion hole 4 is formed at the center, the peripheral portion being surrounded by a flange 3. The support shaft 5 is inserted through the insertion hole 4. An upper portion of the support shaft 5 projects into the processing container 1, and a lower end portion thereof is fixed to a base plate 6 arranged below the processing container 1.
The discharge pipe 2 communicates with a waste liquid tank (not shown).

A rotary chuck 11 is rotatably supported on the support shaft 5. The rotary chuck 11 has a disk-shaped base 12 having a through hole 12a formed in the center thereof. A cylindrical support portion 13 is vertically provided on the lower surface of the base 12, that is, at a position corresponding to the through hole 12a. The support portion 13 is externally fitted to the support shaft 5, and upper and lower portions of the support shaft 5 are rotatably supported by bearings 14, respectively.

A driven pulley 15 is provided on the outer peripheral surface of the lower end of the support portion 13. The base plate 6 has a metal
A motor 16 is provided, and a driving pulley 17 is fitted on a rotating shaft 16a of the motor 16. This drive pulley 17
A belt 18 is stretched between the driven pulley 15 and the driven pulley 15. Therefore, when the motor 16 operates, the support portion 13, that is, the rotary chuck 11 is rotationally driven.

On the upper surface of the base 12 of the rotary chuck 11, four pins 19 are provided upright in the circumferential direction. Engagement portions 21 are formed on the upper ends of the pins 19, and a semiconductor wafer 22 as an object to be processed is detachably held by the engagement portions 21 by engaging peripheral portions thereof. There is.
Therefore, the semiconductor wafer 22 is attached to the rotary chuck 11
It can rotate together with.

The support shaft 5 is provided at its upper end with a conical head portion 5a having a diameter larger than that of the support shaft 5. The support shaft 5 has a gas supply path 31 for an inert gas such as N ₂ whose tip is opened on the upper surface of the head 5a, and a nozzle hole 32 as a nozzle body on the upper surface of the head 5a.
A cleaning liquid supply passage 32 for the cleaning liquid, which is opened via a, is formed along the axial direction. The gas supply path 31 communicates with a gas supply source (not shown).

The inert gas supplied to the gas supply passage 31 is held by the chuck pins 19 on the semiconductor wafer 2
The cleaning liquid L ejected toward the cleaning liquid 2 and supplied to the cleaning liquid supply passage 32 is ejected toward the lower surface of the semiconductor wafer 22 from the nozzle hole 32a.

Above the semiconductor wafer 22 held by the rotary chuck 11, an upper nozzle 37 as a nozzle body for injecting the cleaning liquid L onto the upper surface of the semiconductor wafer 22 is arranged.

The upper nozzle 37 and the cleaning liquid supply passage 32, that is, the nozzle hole 32a are connected to the cleaning liquid L supply device 51 shown in FIG. The supply device 51 has a pure water supply pipe 52 whose base end is connected to a supply source (not shown) which supplies pure water at a predetermined pressure. This pure water supply pipe 52
Is connected to the nozzle hole 32a and the upper nozzle 37, and a first pressure adjusting valve 53 for adjusting the pressure of pure water flowing through the nozzle hole 32a and the upper nozzle 37 is provided in the middle. .

A first opening / closing valve 5 is provided between the first pressure adjusting valve 53 and the nozzle hole 32a and the upper nozzle 37.
4 and the first check valve 55 are sequentially provided. The first check valve 55 is provided so as to prevent the pure water flowing through the pure water supply pipe 52 from flowing backward.

One end of a chemical liquid supply pipe 56 is connected to a portion of the pure water supply pipe 52 between the first check valve 55, the nozzle hole 32a and the upper nozzle 37. The other end of the chemical solution supply pipe 56 is removably inserted in a chemical solution tank 57 containing the chemical solution P in an airtight manner, and has a second check valve at the end located at the inner bottom of the chemical solution tank 57. Valve 58
Is provided.

The second check valve 58, when the end of the chemical liquid supply pipe 56 is withdrawn from the chemical liquid tank 57, the chemical liquid P that has been pressure-fed into the chemical liquid supply pipe 56 as described later escapes, that is, It is designed to prevent air from entering.

A second opening / closing valve 58, a flow rate adjusting valve 59, a flow meter 60 and a third check valve 61 are sequentially provided in the middle of the chemical liquid supply pipe 56 from the chemical liquid tank 57 side. The flow rate adjusting valve 59 can adjust the flow rate of the chemical solution flowing through the chemical solution supply pipe 56, and the flow meter 60 can measure and display the flow rate.

One end of a pressurizing pipe 62 is connected to the chemical liquid tank 57. A second pressure adjusting valve 63 is connected to the middle of the pressurizing pipe 62, and the other end is connected to a nitrogen supply source (not shown) which is stored at a high pressure as a pressurized gas.

The nitrogen supplied from the nitrogen supply source to the pressurizing pipe 62 is depressurized to a predetermined pressure by the second pressure adjusting valve 63 and then supplied to the chemical liquid tank 57. As a result, the inside of the chemical liquid tank 57 is pressurized, and the chemical liquid P in the chemical liquid tank 57 flows out to the chemical liquid supply pipe 56 by the pressure.

The chemical solution P flowing into the chemical solution supply pipe 56 is controlled to a predetermined flow rate by the flow rate adjusting valve 59 and flows into the pure water supply tube 52. Pure water whose pressure is controlled to a predetermined pressure by the first pressure adjusting valve 51 flows through the pure water supply pipe 52. Therefore, the chemical liquid flowing from the chemical liquid supply pipe 56 into the pure water supply pipe 52 is mixed with pure water to become the cleaning liquid L, which flows to the nozzle hole 32a and the upper nozzle 37, and from which the upper and lower surfaces of the rotating semiconductor wafer 22 are rotated. Will be injected at a predetermined pressure.

According to the cleaning apparatus having the above-mentioned structure, the chemical liquid P contained in the chemical liquid tank 57 is supplied from the nitrogen supply source and pressurized by the second pressure adjusting valve 63 to a predetermined pressure to reduce the pressure to nitrogen. Then, the chemical liquid P in the chemical liquid tank 57 flows out to the chemical liquid supply pipe 56, and the flow rate is controlled by the flow rate adjusting valve 59 to flow into the pure water supply pipe 52.

As a result, the pure water supply pipe 52 is connected to the first
The pressure adjusting valve 51 adjusts the pressure (flow rate control) of the pressure adjusting valve 51 to mix it with the flowing pure water to form the cleaning liquid L. Therefore, by setting the pure water flowing through the pure water supply pipe 52 and the chemical liquid P flowing through the chemical liquid supply pipe 56 to a predetermined pressure, the cleaning liquid L in which the pure water and the chemical liquid P are mixed at a predetermined ratio is mixed. It can be supplied to the nozzle hole 32a and the upper nozzle 37 without any work.

The mixing ratio of the chemical liquid P to the pure water is set with high accuracy by adjusting the flow rate of the chemical liquid P with the flow rate adjusting valve 59 with respect to the pure water whose pressure is set by the first pressure adjusting valve 51. can do. That is, since it is possible to prevent the mixing ratio from being different depending on the worker, the cleaning effect of the cleaning liquid L can be maintained constant.

Further, the chemical liquid P is stored in the chemical liquid tank 57,
Since the chemical liquid P is pressurized and mixed in the pure water supply pipe 52, the chemical liquid tank 57 can be made sufficiently smaller than a conventional preparation tank for storing the premixed cleaning liquid L. it can. Therefore, the space for installing the chemical liquid tank 57 can be small, so that the installation thereof is not only easy, but also it is less likely to get in the way.

Further, a flow rate adjusting valve 59 is attached to the chemical solution supply pipe 56.
Since the chemical liquid tank 57 is simply provided, the chemical liquid tank 57 is simply pressurized.
The flow rate of the chemical liquid P flowing from the chemical liquid supply pipe 56 into the pure water supply pipe 52 can be controlled more accurately than in the case of supplying the chemical liquid P. Therefore, the cleaning liquid L according to the mixing ratio of the chemical liquid P
Since the cleaning ability of the semiconductor wafer 22 to be cleaned can be reliably set, the degree of contamination of the semiconductor wafer 22 to be cleaned, the type of contamination, or the chemical solution P
The cleaning ability of the cleaning liquid L can be controlled according to the type of the cleaning liquid L.

Pure water, nitrogen, and the like are supplied to the vicinity of the cleaning processing apparatus at a predetermined pressure in a pipe in an ordinary semiconductor factory. Therefore, in order to supply these pure water, nitrogen, etc. to the cleaning processing apparatus, it is not necessary to purposely install their supply sources near the cleaning processing apparatus.

On the other hand, when the chemical solution P in the chemical solution tank 57 is supplied under pressure for a predetermined time, when the chemical solution P is exhausted, the chemical solution tank 57 is replaced to replenish it. When exchanging the chemical liquid tank 57, even if the end of the chemical liquid supply pipe 56 is pulled out from the chemical liquid tank 57, the second check valve 58 is provided at the end, so the chemical liquid supply pipe 56 The chemical liquid P inside does not escape and air does not enter inside.

Therefore, when replacing the chemical liquid tank 57 with a new one and restarting the use, it is not necessary to bleed the chemical liquid supply pipe 56. Therefore, not only the reuse at the time of replacement is easy, but also the air bleeding is performed. For the above chemical solution supply pipe 56
The chemical liquid P does not have to be wasted.

[0041]

As described above, according to the first aspect of the invention, the chemical solution stored in the chemical solution tank is pressurized and supplied to the pure water supply pipe through which the pure water flows, so that the pure water is supplied with the predetermined chemical solution. Since the cleaning liquid is mixed at a ratio of 1, the mixing work of mixing the chemical liquid with pure water is unnecessary.

Moreover, since the chemical liquid tank for storing the chemical liquid can be made sufficiently smaller than the tank for storing the pre-mixed cleaning liquid, the chemical liquid tank can be installed more easily than the conventional tank for storing the cleaning liquid. Become.

According to the second aspect of the present invention, the flow rate of the chemical liquid flowing through the chemical liquid supply pipe is controlled by the adjusting means provided in the middle portion of the chemical liquid supply pipe, whereby the kind of chemical liquid and the degree of contamination of the object to be cleaned are controlled. It is possible to reliably adjust the cleaning ability of the cleaning liquid according to the above.

According to the third aspect of the present invention, since the check valve is provided at the end portion of the chemical solution supply pipe which is inserted into the chemical solution tank, even if the chemical solution supply pipe is pulled out from the chemical solution tank, air is not introduced into the chemical solution supply pipe. The check valve blocks entry.

Therefore, since it is not necessary to bleed the chemical solution supply pipe when replacing the chemical solution tank, it is easy to replace the chemical solution tank and use it, and it takes extra time for venting the chemical solution tank. Never.

[Brief description of drawings]

FIG. 1 is a piping system diagram showing an embodiment of the present invention.

FIG. 2 is a schematic configuration diagram of the cleaning processing apparatus.

[Explanation of symbols]

 32a ... Nozzle hole (cleaning nozzle), 37 ... Upper nozzle (cleaning nozzle), 52 ... Pure water supply pipe, 56 ... Chemical solution supply pipe, 57 ... Chemical solution tank, 58 ... Second check valve, 59 ... Flow rate adjusting valve (Adjusting means), 62 ... Pressurizing tube.

Claims (3)

[Claims] 1. A cleaning processing apparatus for cleaning an object to be cleaned by jetting a cleaning liquid, which is a mixture of a chemical liquid and pure water, from a cleaning nozzle, and a pure water which is connected to the cleaning nozzle and supplies the pure water at a predetermined pressure. A water supply pipe, a chemical liquid tank containing the chemical liquid, a chemical liquid supply pipe having one end connected to the chemical liquid tank and the other end connected to the cleaning nozzle, and one end connected to the chemical liquid tank and the chemical liquid from the other end. A cleaning processing apparatus, comprising: a pressurizing pipe to which a pressurized gas for pressurizing the chemical liquid in the tank is supplied. 2. The cleaning treatment apparatus according to claim 1, wherein an adjusting means for adjusting a flow rate of the chemical liquid flowing through the chemical liquid supply pipe is provided in a middle portion of the chemical liquid supply pipe. 3. A check valve is provided at one end of the chemical liquid supply pipe for preventing the chemical liquid pumped by the pressurizing pipe in the chemical liquid supply pipe from coming out from the one end. The cleaning processing apparatus according to claim 1 or 2.