JP3343776B2 - Cleaning treatment apparatus and cleaning treatment method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cleaning apparatus and a cleaning method for immersing an object to be processed, such as a semiconductor wafer or an LCD glass substrate, in a cleaning solution such as a chemical solution or pure water.

[0002]

2. Description of the Related Art Generally, in a manufacturing process of a semiconductor manufacturing apparatus, an object to be processed (hereinafter, referred to as a wafer or the like) such as a semiconductor wafer or an LCD glass is made of, for example, ammonia water (NH).
A cleaning treatment method of sequentially immersing in a cleaning tank in which a cleaning solution such as a chemical solution such as 4OH) or hydrofluoric acid (HF) or a rinsing solution (pure water) is stored for cleaning is widely used.

As shown in FIG. 9, a conventional cleaning apparatus of this kind stores a chemical solution such as diluted hydrofluoric acid (DHF) and a chemical solution tank a for circulating and supplying a rinsing solution such as pure water. And a washing tank b overflowing therewith. According to this cleaning treatment apparatus, the circulation pipe c stored in the chemical solution tank a and attached to the chemical solution tank a
An object to be processed, for example, a wafer W is immersed in dilute hydrofluoric acid (DHF) circulated through the substrate to remove particles adhering to the surface of the wafer W, chemically and physically adsorbed Ni, Cr, etc. Heavy metal or natural oxide film can be removed. Thereafter, the wafer W is taken out of the chemical solution tank a, transported into the cleaning tank b, and stored in the cleaning tank b, and in the overflowing pure water.
To remove the chemical solution attached to the surface of the wafer W.

[0004]

However, this type of conventional cleaning apparatus has a plurality of processing tanks, ie, a chemical tank a and a cleaning tank b, and requires many piping facilities. In addition to the above-mentioned piping, piping equipment such as a weighing tank for chemical and pure water, a pump, a damper, a filter, and a large number of valves are required, so that there has been a problem that the apparatus becomes large and the equipment cost increases. Further, since the number of times of the object to be processed, for example, the wafer W, passing through the gas-liquid interface increases, it is necessary to consider the possibility of particles adhering to the wafer W and the uniformity of etching.

The present invention has been made in view of the above circumstances, and aims at simplifying the structure and improving the processing efficiency.
Further, it is an object of the present invention to provide a cleaning apparatus and a cleaning method capable of reducing the number of passing through a gas-liquid interface to reduce adhesion of particles and improve etching uniformity.

[0006]

In order to achieve the above object, the present invention is configured as follows.

According to a first aspect of the present invention, there is provided a cleaning processing apparatus comprising: a cleaning tank for storing a cleaning liquid and immersing an object to be processed in the cleaning liquid to clean the surface thereof; and the cleaning tank and a pure water supply source. A cleaning liquid supply pipe to be connected, a chemical storage vessel for storing a chemical liquid, a chemical supply pipe connecting the cleaning liquid supply pipe to the chemical storage vessel via open / close switching means, and a chemical transport gas in the chemical storage vessel. And a gas supply means for supplying a gas pressure adjusting means to a gas supply pipe connecting the chemical solution storage container and a gas supply source.
When a liquid level detecting means is attached to the chemical storage container,
In addition, based on the detection signal from the liquid level detection means,
The liquid medicine in the vessel is always kept constant . In this case, an inert gas can be used as the chemical transport gas (claim 3).

[0008] With this configuration, by supplying a gas at a predetermined pressure by the gas pressure adjusting means to the chemical in the chemical storage container, a predetermined amount of the chemical is supplied to the cleaning tank. A chemical solution having a predetermined concentration by being mixed in water can be stored in the cleaning tank. Therefore, the gas pressure
By supplying a chemical solution of a predetermined concentration into the cleaning tank by adjustment ,
Particles, metal contaminants, natural oxide films, and the like attached to the surface of the object to be processed can be removed. Also medicine
Maintain a constant amount of drug solution stored in the liquid storage container
Can be controlled without being affected by the amount of stored drug solution.
It is possible to keep the amount of chemical solution injected into pure water constant.
In addition, the concentration of the drug solution can be kept constant .

(2) The cleaning apparatus according to the second aspect of the present invention includes a cleaning tank for storing the cleaning liquid and immersing the object to be processed in the cleaning liquid to clean the surface thereof, and the cleaning tank and the pure water supply source. A cleaning liquid supply pipe to be connected, a chemical storage vessel for storing a chemical liquid, a chemical supply pipe connecting the cleaning liquid supply pipe to the chemical storage vessel via open / close switching means, and a chemical transport gas in the chemical storage vessel. Gas supply means for supplying, and pure water flow rate detection means for detecting a flow rate of pure water flowing through the cleaning liquid supply pipe provided in the cleaning liquid supply pipe, wherein the gas supply means comprises: A gas supply pipe connecting the container and the gas supply source is provided with gas pressure adjusting means, and the gas pressure adjusting means is controlled based on a detection signal detected by the pure water flow rate detecting means. It is characterized by. In this case, an inert gas can be used as the chemical transport gas (claim 3).

With this configuration, the pure water supply amount can be detected by the pure water flow rate detecting means to detect fluctuations in the pure water flow rate, and the gas pressure adjusting means can be controlled based on the detection signal. As a result, a chemical solution whose concentration has been accurately adjusted can be supplied into the cleaning tank.

(3) The cleaning apparatus according to the fourth aspect of the present invention is the cleaning apparatus according to the first or second aspect, wherein the cleaning tank comprises an inner tank for immersing an object to be processed, and an opening of the inner tank. An outer tank that covers the outer edge, and a bottom part of the outer tank,
The cleaning liquid supply unit provided in the inner tank is connected to a circulation pipe, and a circulation pump, a temperature adjusting unit, and a filter are provided in the circulation pipe.

With this configuration, the chemical solution stored in the cleaning tank can be circulated and supplied as needed. Therefore, it is possible to reduce the consumption of the chemical solution, and it is possible to effectively use the chemical solution and reduce particles by filtering.

According to a fourth aspect of the present invention, there is provided the cleaning apparatus according to the first or second aspect, wherein the gas supply pipe of the gas supply means includes a plurality of opening / closing means and a throttle mechanism. A branch path is provided, and each of the opening and closing means is formed so as to be selectively opened and closed.
In this case, the above-mentioned branch paths for gas adjustment may be arranged in parallel with each other, or may be arranged in series.

With this configuration, each opening / closing means can be selectively opened / closed, so that the gas pressure can be adjusted over a wide range. Therefore, a chemical solution whose concentration has been accurately adjusted can be supplied into the cleaning tank.

(5) In the cleaning apparatus according to the sixth aspect of the present invention, in the cleaning apparatus according to the second aspect, a liquid level detecting means is attached to the chemical solution storage container, and a detection signal from the liquid level detecting means is provided. The liquid medicine in the liquid medicine storage container is always kept constant on the basis of this.

With this configuration, the amount of the chemical stored in the chemical storage container can be kept constant, so that the injection of the chemical into pure water is not affected by the amount of the chemical stored. The amount can be constant and the concentration of the drug solution can be constant.

(6) The cleaning apparatus according to claim 7 is the cleaning apparatus according to any one of claims 1, 2 and 6, wherein the chemical storage container has a circular cross section having a height at least equal to or less than a diameter. Characterized by being formed by a tank of

With this configuration, it is possible to suppress the influence of the fluctuation of the stored amount of the drug solution stored in the drug solution storage container and to make the amount of the drug solution injected into pure water constant.

(7) The cleaning method according to claim 8, wherein the object to be processed is immersed in a cleaning liquid stored in the cleaning tank to wash the surface of the object to be processed. A first cleaning treatment step of overflowing a chemical solution diluted to a predetermined concentration into pure water supplied to wash the object to be processed, and, when the diluted chemical solution reaches a predetermined concentration, the pure water A second cleaning treatment step of adjusting the temperature of the diluent in the cleaning tank to a predetermined temperature and circulating the diluted liquid in the cleaning tank to wash the object to be processed in a state in which both the supply of the chemical liquid and the chemical liquid are stopped; And a third cleaning process step of cleaning the chemical solution adhering to the object to be processed by overflowing the object.

According to the cleaning method of the present invention, when the diluted chemical reaches a predetermined concentration after the chemical cleaning, the supply of the pure water and the chemical is stopped, and the diluted chemical in the cleaning tank is stopped. By controlling the temperature to a predetermined temperature and circulating the object to wash the object to be processed, it is possible to reduce the consumption of the chemical solution, and it is possible to effectively use the chemical solution and reduce the particle adhesion by the filtering effect.

According to a ninth aspect of the present invention, there is provided a cleaning method for cleaning a surface of a processing object by immersing the processing object in a cleaning liquid stored in the cleaning tank. The first cleaning step of washing the object by overflowing water, and overflowing a chemical solution diluted to a predetermined concentration in the pure water continuously supplied in the cleaning tank, the object to be processed In the second washing step of washing, and when the supply of both the pure water and the chemical solution is stopped when the concentration of the diluted chemical solution reaches a predetermined concentration, the temperature of the diluted chemical solution in the cleaning tank is adjusted to a predetermined temperature and circulated. The method further comprises a third cleaning step of cleaning the object to be processed and a fourth cleaning step of overflowing pure water in the cleaning tank to wash a chemical solution attached to the object.

According to the ninth aspect of the present invention, when the diluted chemical reaches a predetermined concentration after the pure water cleaning and the chemical cleaning, the supply of both the pure water and the chemical is stopped, and the dilution in the cleaning tank is stopped. By cleaning the object by adjusting the temperature of the chemical solution to a predetermined temperature and circulating the same, the consumption of the chemical solution can be reduced, and the effective use of the chemical solution and the reduction of particle adhesion due to the filtering effect can be achieved.

[0023]

Embodiments of the present invention will be described below in detail with reference to the drawings. In this embodiment, a case where the present invention is applied to a semiconductor wafer cleaning processing system will be described.

FIG. 1 is a schematic plan view showing an example of a cleaning system to which a cleaning apparatus according to the present invention is applied, and FIG. 2 is a schematic side view of a part of FIG.

The cleaning system includes a transfer unit 2 for loading and unloading a container, for example, a carrier 1, which stores a semiconductor wafer W (hereinafter, referred to as a wafer), which is an object to be processed, in a horizontal state; It mainly includes a processing unit 3 that performs a liquid process such as a cleaning liquid and a drying process, and an interface unit 4 that is located between the transfer unit 2 and the processing unit 3 and that performs transfer of the wafer W, position adjustment, and posture change. Have been.

The transport section 2 includes a carry-in section 5 and a carry-out section 6 which are provided alongside one end of the cleaning system. The loading unit 5 includes a receiving unit 5a that receives the carrier 1 from the upper transport mechanism 7, and a receiving unit 5a.
Transfer section 5 on which carrier 1 is transported horizontally from
b, a carrier lifter 8 for transporting the carrier 1 between an upper position and a carry-in port (not shown) of the interface unit 4 is provided in the delivery unit 5b. Also,
A carrier lifter 8 that transports the carrier 1 between a carry-out port (not shown) of the interface unit 4 and an upper portion is disposed in the carry-out unit 6. So that the carrier 1 can be transferred to the carrier standby unit 9 provided above the interface unit 4 and the empty carrier 1 can be received from the carrier standby unit 9. (See FIG. 2).

The interface section 4 includes a partition wall 4c.
First chamber 4a adjacent to the transport section 2 partitioned by
And a second chamber 4b adjacent to the processing unit 3. Then, in the first chamber 4a, a plurality of wafers W are taken out from the carrier 1 of the loading section 5 (specifically, the transfer section 5b), and are transported in the horizontal direction (X, Y direction) and the vertical direction (Z direction). Direction) and a wafer unloading arm 10 that can be rotated (θ direction), a notch aligner 11 that aligns notches provided on the wafer W, and an interval adjustment that adjusts an interval between a plurality of wafers W unloaded by the wafer unloading arm 10. A first attitude conversion device 12 that includes a mechanism (not shown) and converts a horizontal state of the wafer W to a vertical state is provided.

In the second chamber 4b, a plurality of processed wafers W are transferred from the processing section 3 in a vertical state. And a plurality of wafers W that have been converted to a horizontal state by the second attitude conversion device 13 are received and stored in the empty carrier 1 transported to the wafer receiving unit 14. A horizontal (X, Y direction), vertical (Z direction) and rotatable (θ direction) wafer storage arm 15 is provided. The wafer receiving unit 14 includes the wafer receiving unit 1
A carrier lifter 8 for transporting the carrier between the carrier waiting unit 9 and the carrier waiting unit 9 is provided. Further, the carrier waiting section 9 places the empty carrier 1 after the wafer W has been delivered by the wafer delivery section 5b or the carriage 1 containing the wafer W in the carrier 1 by the wafer receiving section 14 at a predetermined waiting position or wafer reception. A carrier transfer robot 16 that moves the carrier 1 containing the wafer W transferred from the unit 14 to the carrier standby unit 9 above the unloading unit 6 is provided.

On the other hand, the processing section 3 includes a first processing unit 19 for removing particles and organic contaminants adhering to the wafer W, a second processing unit 18 for removing metal contaminants adhering to the wafer W, A third processing unit 17 for removing an oxide film adhered to the wafer W and a chuck cleaning unit 20 are linearly arranged. Note that a drying processing unit 21 is provided above the third processing unit 17. In this case, the cleaning processing apparatus according to the present invention is applied to the third processing unit 17. Also,
A transport path 22 provided to extend to the interface unit 4 from a position facing each of these units 17 to 20.
A wafer transfer chuck 23 that can rotate in the X and Y directions (horizontal direction), the Z direction (vertical direction), and rotate (θ) is provided.

Next, a cleaning apparatus according to the present invention will be described. First Embodiment FIG. 3 is a schematic sectional view showing a first embodiment of the cleaning apparatus according to the present invention.

The cleaning apparatus 17 stores a cleaning solution such as a chemical solution such as a dilute solution (DHF) of hydrofluoric acid (HF) or a rinsing solution such as pure water, and stores an object to be processed such as a semiconductor wafer W (hereinafter referred to as a semiconductor wafer W). A cleaning tank 30 for immersing a wafer in the cleaning tank 30 to clean the surface thereof, a cleaning liquid supply nozzle 32 provided in the cleaning tank 30 for connecting the cleaning tank 30 and a pure water supply source 31, and a pure water supply A cleaning liquid supply pipe 33 that connects to the source 31, a chemical liquid storage container 34 that stores a chemical such as hydrofluoric acid (HF), and a cleaning liquid supply pipe 33 and a chemical liquid storage via an injection opening / closing switching valve 35 (opening / closing switching means). A chemical solution supply pipe 36 connecting the container 34 and a chemical solution storage container 34
N2 gas supply means 37 (gas supply means) for supplying an inert gas such as a gas for transporting a chemical solution, for example, nitrogen (N2) gas into the inside.
It is mainly composed of An opening / closing valve 31 </ b> A is provided on the cleaning liquid supply pipe 33 on the discharge port side of the pure water supply source 31.

In this case, the cleaning tank 30 is composed of an inner tank 30a for storing the cleaning liquid and an outer tank 30b covering the outer edge of the opening of the inner tank 30a. A discharge pipe 38 is connected to the provided discharge port. Further, the N2 gas supply means 37 is connected to the N2 gas supply pipe 40 connecting the chemical solution storage container 34 and the N2 gas supply source 39 with N2 gas pressure adjusting means such as a regulator 41, an on-off valve 42, a pressure fluctuation absorbing damper 43, The filter 44 is provided.

Further, a pure water flow detecting means such as a flow meter 4 is provided on the side of the pure water supply source 31 in the cleaning liquid supply pipe 33.
A detection signal of the flow rate of pure water flowing through the cleaning liquid supply pipe 33 detected by the flow meter 45 is transmitted to control means, for example, a central processing unit 46 (CPU). The control signal that has been subjected to the comparison operation processing with the stored information is transmitted to the regulator 41 so that the regulator 41 can operate.
It should be noted that, if any error occurs in the flow meter 45, an alarm is displayed from the CPU 46.

The chemical solution storage container 34 is formed of, for example, a cylindrical tank having a circular cross section and a bottom, and the diameter A of the tank is larger than at least the height B of the tank (A ≧ B). Have been. As described above, by forming the diameter A of the drug solution storage container 34 at least equal to or higher than the height B of the drug solution storage container 34, the influence of the fluctuation of the storage amount of the drug solution (HF) stored in the drug solution storage container 34 is suppressed. Thus, the injection amount of the chemical solution (HF) into the pure water can be made constant.

A liquid level detecting means, for example, a level sensor 47 for detecting the liquid level of the chemical liquid, ie, HF, stored in the chemical liquid storage vessel 34 is provided outside the chemical liquid storage vessel 34. A detection signal detected by the sensor 47 is transmitted to the CPU 46, and based on the control signal from the CPU 46, the HF supply source 48 and the chemical solution storage container 34
The opening / closing valve 50 provided in the HF supply pipe 49 connecting between the opening and closing can be opened and closed. With this configuration, the HF stored in the drug solution storage container 34
Can be kept constant, so that the amount of HF injected into pure water can be made constant without being affected by the amount of stored HF, and the concentration of HF can be made constant. .

In the cleaning apparatus constructed as described above, the cleaning liquid supply from the pure water supply source 31 is performed by operating the injection opening / closing switching valve 35 to make the pure water supply source 31 and the cleaning tank 30 communicate with each other. Pure water is stored in the cleaning tank 30 through the pipe 33 and the cleaning liquid supply nozzle 32, and the plurality of wafers W that overflow and are accommodated in the cleaning tank 30 can be cleaned. Also, the injection opening / closing switching valve 3
5 is operated to open the chemical supply pipe 36 side in a state where the pure water from the pure water supply source 31 is circulated.
By opening the on-off valve 42 interposed in the gas supply pipe 40 and operating the regulator 41, N2 gas at a predetermined pressure set in advance by the simulator is supplied into the chemical solution storage container 34, and the chemical solution storage container 34 is opened. A predetermined amount of the chemical, ie, HF, flows from the inside of the cleaning liquid supply pipe 33 via the chemical liquid supply pipe 36 into the cleaning liquid supply pipe 33, and is diluted with pure water to have a predetermined concentration of the chemical, ie, diluted hydrofluoric acid (DHF), in the cleaning tank 30. Supplied. As a result, DHF having a predetermined concentration set in advance by the simulator is stored in the cleaning tank 30, and particles, oxide films, and the like that overflow and adhere to the surface of the wafer W accommodated in the cleaning tank 30 are removed. be able to.

Second Embodiment FIG. 4 is a schematic sectional view showing a second embodiment of the cleaning apparatus according to the present invention.

In the second embodiment, the adjustment range of the N2 gas pressure is widened to enable fine adjustment of the concentration of a chemical such as HF. That is, a plurality of (three cases are shown in the drawing) opening / closing means such as the first
Or third to third on-off valves 51a to 51c and a throttle mechanism such as orifices 52a to 52c.
This is a case where the gas adjusting branch passages 53a to 53c are arranged in parallel with each other, and each of the on-off valves 51a to 51c is formed so as to be selectively opened and closed.

With this configuration, one of the on-off valves 51a to 51c can be selectively opened and closed, or any of a plurality of on-off valves 51a, 51b and 51c can be opened and closed simultaneously. Accordingly, the N2 gas pressure can be adjusted to an arbitrary set pressure, and the HF discharge amount can be adjusted. Therefore, the chemical (H
Fine adjustment of the concentration of F) becomes possible, and the chemical solution treatment can be performed by supplying HF having a concentration corresponding to the type and number of wafers W. In addition, all the on-off valves 51a to 51
By releasing c and supplying high concentration HF to the cleaning tank 30, it is possible to adopt a method of, for example, speeding up the start of chemical solution treatment.

In the second embodiment, the case where the number of N2 gas adjusting branch passages 53a to 53c and the number of on-off valves 51a to 51c are three has been described. Of course, a plurality other than three, for example, two or four or more N2 A branch path for gas adjustment and an on-off valve may be provided. In the second embodiment,
Opening / closing means includes opening / closing valves 51a-51c and orifices 52a-
Although the description has been made of the case including 52c, the opening / closing means may be constituted by a flow control valve instead. Further, in the above description, the opening / closing means is the first to third N2 comprising the opening / closing valves 51a to 51c and the orifices 52a to 52c.
Although the case where the gas adjusting branches 53a to 53c are arranged in parallel with each other has been described, the N2 gas adjusting branches need not necessarily be arranged in parallel, and may be arranged in series.
That is, as shown in FIG. 5, a plurality of (three in the drawing) opening / closing means for adjusting the N2 gas, for example, first to third valves 54a to 54c may be arranged in series.

In this case, the first valve 54a is formed by an on-off valve, the second valve 54b is formed by a flow control valve capable of adjusting a large flow rate and a small flow rate, and the third valve 54c is formed by a large flow rate control valve. The flow control (adjustment) as described below can be made possible by forming a flow control valve capable of adjusting the flow rate and the medium flow rate. That is, when supplying a small flow rate of N2 gas, the first valve 54a is opened, the second valve 54b is set to a small flow rate, and the third valve 54c is set to a medium flow rate. When supplying a medium flow rate of N2 gas, the first valve 54a is opened, the second valve 54b is set to a large flow rate, and the third valve 54c is set to a medium flow rate. When supplying a large flow rate of N2 gas, the first valve 54a is opened, and the second valve 54b is set to a large flow rate.
The third valve 54c is set to a large flow rate. When the supply of the N2 gas is stopped, the first valve 54a may be closed.

In the second embodiment, the other parts are the same as those in the first embodiment, and the same parts are denoted by the same reference numerals and description thereof will be omitted.

Next, an example of a procedure of a cleaning process using the cleaning apparatus of the first embodiment and the second embodiment will be described with reference to FIG. First, the injection opening / closing switching valve 3
5, the pure water supply source 31 and the cleaning tank 30 are communicated with each other, pure water is supplied from the cleaning liquid supply nozzle 32 into the cleaning tank 30, and the pure water is stored in the cleaning tank 30. The wafer W is immersed in the wafer and the pure water overflows (first cleaning step: FIG. 6A).

Next, by operating the injection opening / closing switching valve 35, the chemical solution supply pipe 3 is supplied with the pure water from the pure water supply source 31 flowing.
6 is opened, and in this state, the on-off valve 42 provided in the N2 gas supply pipe 40 is opened, and the regulator 41 is operated or predetermined on-off valves 51a to 51c or the valves 54a to 54c are opened together with the regulator 41. Then
N2 gas at a predetermined pressure is supplied into the chemical storage container 34. As a result, a predetermined amount of the chemical solution, that is, HF, is supplied from the chemical solution storage container 34 through the chemical solution supply tube 36 to the cleaning solution supply tube 3.
3, a chemical solution diluted with pure water and having a predetermined concentration, that is, diluted hydrofluoric acid (DHF) is supplied into the cleaning tank 30, and the wafer W is immersed in DHF,
F overflows to remove metal contaminants adhering to the surface of the wafer W or to remove an oxide film or the like on the surface of the wafer W (second cleaning step: FIG. 6B).

Next, the injection opening / closing switching valve 35 is operated to bring the pure water supply source 31 into communication with the washing tank 30 again, while the opening / closing valves 42; 51a to 51c; Pure water is supplied to the inside to replace DHF with pure water, and the wafer W is immersed in the pure water, and the pure water overflows to remove a chemical solution, that is, HF attached to the wafer W. {Third Cleaning Step: FIG. 6 (c)｝.

As described above, after cleaning the wafer W by overflowing the pure water in the cleaning tank 30, a chemical solution, eg, HF, diluted to a predetermined concentration is added to the pure water continuously supplied to the cleaning tank 30. Overflow to wash the wafer W,
Thereafter, the pure water overflows again in the cleaning tank 30 to clean the HF adhering to the wafer W, so that the in-plane uniformity of the wafer W is reduced when the pure water is replaced with DHF. By replacing with pure water, the uniformity is restored, so that high etching uniformity is obtained.
Therefore, according to this cleaning method, the cleaning efficiency can be improved.

Third Embodiment FIG. 7 is a schematic sectional view showing a third embodiment of the cleaning apparatus according to the present invention.

The third embodiment is a case in which the consumption of the chemical solution is reduced and the effective use of the chemical solution is achieved. That is, the discharge port provided at the bottom of the outer tank 30b constituting the cleaning tank 30 is connected to the cleaning liquid supply nozzle 32 (cleaning liquid supply unit) provided in the cleaning tank 30 through the circulation pipe 60, and Opening / closing valves 61, 61 are sequentially provided in the circulation pipeline 60 from the discharge port side toward the cleaning liquid supply nozzle 32 side.
Metal contaminants and oxide films adhering to the surface of the wafer W by circulating and supplying the chemical solution such as HF stored in the cleaning tank 30 via the circulation pump 62, the temperature adjustment mechanism 63, the filter 64, and the valve 65. Is removed.

In the third embodiment, the other parts are the same as those in the first and second embodiments. Therefore, the same parts are denoted by the same reference numerals and the description thereof will be omitted.

Next, an example of a procedure of a cleaning process using the cleaning device of the third embodiment will be described with reference to FIG. First, the injection opening / closing switching valve 35 is operated to bring the pure water supply source 31 into communication with the cleaning tank 30, and pure water is supplied from the cleaning liquid supply nozzle 32 into the cleaning tank 30. While immersing the wafer W in pure water,
Overflow of pure water. First cleaning process: Fig. 8
(A)｝.

Next, by operating the injection opening / closing switching valve 35, the chemical solution supply pipe 3 is supplied with the pure water from the pure water supply source 31 flowing.
When the open / close valve 42 provided in the N2 gas supply pipe 40 is opened and the regulator 41 is operated or the predetermined open / close valves 51a to 51c are opened together with the regulator 41 in this state, the predetermined pressure is reached. Is supplied into the chemical storage container 34. As a result, a predetermined amount of the chemical liquid, for example, HF flows from the chemical liquid storage container 34 into the cleaning liquid supply pipe 33 via the chemical liquid supply pipe 36, and DHF having a predetermined concentration diluted with pure water is supplied into the cleaning tank 30. The wafer W is immersed in the DHF, and the DHF overflows to remove metal contaminants or oxide films attached to the surface of the wafer W. Second cleaning step: FIG.
(B)｝.

Next, the on / off valve 31A is closed to stop the supply of pure water, and the injection on / off switching valve 35 and the on / off valve 42;
After closing the supply of DHF by closing 51a to 51c, the on-off valve 61 provided in the circulation line 60 is opened,
The circulation pump 62 is driven to drive the D stored in the cleaning tank 30.
The temperature of the HF is adjusted to a predetermined temperature by the temperature adjusting mechanism 63, and the HF is filtered and filtered and circulated and supplied by the filter 64 to remove metal contaminants or oxide films attached to the surface of the wafer W immersed in the DHF. Continue {third cleaning step: FIG. 8 (c)}.

Next, the on-off valve 31A is opened to bring the pure water supply source 31 into communication with the washing tank 30 again, while the injection on-off switching valve 35 and the on-off valve 42; 51a to 51c are kept closed. Then, pure water is supplied into the cleaning tank 30 to replace DHF with pure water, so that the wafer W is immersed in the pure water, and the chemical liquid, ie, HF, which adheres to the wafer W by overflowing the pure water is removed. Fourth cleaning step: FIG.

As described above, after cleaning the wafer W by overflowing the pure water in the cleaning tank 30, a chemical solution, eg, DHF, diluted to a predetermined concentration is added to the pure water continuously supplied to the cleaning tank 30. The wafer W is overflowed to wash the wafer W. Thereafter, the supply of DHF is stopped, and the DHF stored in the washing tank 30 is cleaned while being circulated and supplied while controlling the temperature and filtering. To clean the HF adhering to the wafer W by overflowing the wafer W, the in-plane uniformity of the wafer W is reduced when the pure water is replaced with the DHF, but the uniformity is reduced by replacing the DHF with the pure water again. Since the properties are restored, high etching uniformity can be obtained, and the cleaning efficiency can be improved. In addition, by controlling the temperature of a chemical solution such as DHF stored in the cleaning tank 30 and circulating the solution while filtering,
DHF consumption can be reduced, and DHF
Can be effectively used and particle adhesion can be reduced by filtering.

In the above embodiment, the case where the cleaning apparatus of the present invention is applied to the third processing unit 17 has been described.
18 can of course be applied. In the above embodiment, the case where the cleaning apparatus and the cleaning method of the present invention are applied to a semiconductor wafer cleaning processing system has been described. However, it is needless to say that the present invention can also be applied to LCD glass substrates other than semiconductor wafers. .

[0056]

As described above, according to the present invention, because of the above-described configuration, the following excellent effects can be obtained.

(1) According to the first aspect of the present invention, gas
By adjusting the pressure, a chemical solution having a predetermined concentration can be supplied into the cleaning tank to remove particles, metal contaminants, natural oxide films, etc. attached to the surface of the object to be processed.
The number of constituent members can be reduced and the size of the device can be reduced.
In addition, the amount of drug solution stored in the drug solution storage container is kept constant.
Is affected by the amount of stored chemical solution.
The amount of chemical solution injected into pure water without any
At the same time, the concentration of the drug solution can be kept constant. I
Accordingly, the processing efficiency can be improved, and the number of gas-liquid interface passages can be reduced to reduce the adhesion of particles and improve the etching uniformity.

(2) According to the second aspect of the present invention, the gas
A chemical solution of a predetermined concentration is supplied to the cleaning tank only by adjusting the pressure.
Particles and metal contamination adhering to the surface of the workpiece
It can remove dyes or natural oxide film
Thus, the number of components can be reduced and the size of the apparatus can be reduced.
You. In addition to improving processing efficiency, gas-liquid interface
Reduce the number of particles to reduce particle adhesion and etch
This improves the uniformity of the motor. Further, the supply amount of the pure water can be detected by the pure water flow rate detecting means, it is possible to control the gas pressure adjusting means based on the detection signal, the exact concentration adjusted drug solution in the cleaning tank Can be supplied.

(3) According to the fourth aspect of the present invention, the chemical solution stored in the cleaning tank can be circulated and supplied as necessary, so that in addition to the above (1) or (2) , The consumption amount of the chemical solution can be reduced, and the effective use of the chemical solution can be achieved.

[0060] (4) According to the fifth aspect of the present invention, by selectively opening and closing the respective switching means, it is possible to perform pressure adjustment range of the gas over a wide range, the (1) or (2)
In addition to the above, a chemical solution whose concentration has been accurately adjusted can be supplied into the cleaning tank.

(5) According to the sixth aspect of the present invention, the amount of the chemical solution stored in the chemical solution storage container can be kept constant, so that the chemical solution is added to the above (1) or (2). The amount of the chemical solution injected into the pure water can be made constant without being affected by the stored amount of the chemical solution, and the concentration of the chemical solution can be made constant.

(6) According to the seventh aspect of the present invention,
In addition to (1), (2) or (5) , it is possible to suppress the influence of the fluctuation of the storage amount of the drug solution stored in the drug solution storage container and to make the injection amount of the drug solution into pure water constant. .

(7) According to the eighth aspect of the present invention, after the cleaning of the chemical solution, the supply of the diluent chemical solution is stopped, and the temperature of the diluent chemical solution in the cleaning tank is adjusted to a predetermined temperature and circulated, whereby the object to be processed is circulated. Is cleaned, the consumption amount of the chemical solution can be reduced, and the adhesion of particles due to the effective use of the chemical solution and the filtering effect can be achieved.

(8) According to the ninth aspect of the present invention, after the pure water cleaning and the chemical cleaning, the supply of the diluting chemical is stopped, and the temperature of the diluting chemical in the cleaning tank is adjusted to a predetermined temperature and circulated. Since the object to be processed is cleaned by using the cleaning liquid, the consumption of the chemical solution can be reduced, and the effective use of the chemical solution and the reduction of particle adhesion due to the filtering effect can be achieved.

[Brief description of the drawings]

FIG. 1 is a schematic plan view of a cleaning system to which a cleaning apparatus according to the present invention is applied.

FIG. 2 is a schematic side view of a part of the cleaning processing system.

FIG. 3 is a schematic sectional view showing a first embodiment of the cleaning apparatus according to the present invention.

FIG. 4 is a schematic sectional view showing a second embodiment of the cleaning apparatus according to the present invention.

FIG. 5 is a schematic sectional view showing another embodiment of the second embodiment.

FIG. 6 is a schematic sectional view showing a procedure of a cleaning method using the cleaning apparatuses of the first embodiment and the second embodiment.

FIG. 7 is a schematic sectional view showing a third embodiment of the cleaning apparatus according to the present invention.

FIG. 8 is a schematic cross-sectional view illustrating a procedure of a cleaning method using the cleaning apparatus of the third embodiment.

FIG. 9 is a schematic sectional view showing an example of a procedure of a conventional cleaning method.

[Explanation of symbols]

W Semiconductor wafer (object to be processed) 30 Cleaning tank 30a Inner tank 30b Outer tank 31 Pure water supply source 33 Cleaning liquid supply pipe 34 Chemical storage tank 35 Injection open / close switching valve (open / close switching means) 36 Chemical liquid supply pipe 37 N2 gas supply means ( Gas supply means) 39 N2 gas supply source 40 N2 gas supply pipe 41 Regulator (gas pressure adjustment means) 42 Open / close valve 45 Flow meter (Pure water flow rate detection means) 46 CPU 47 Level sensor (Liquid level detection means) 48 HF supply source 49 HF supply pipe 50 On-off valve 51a-51c On-off valve (opening / closing means) 52a-52c Orifice (throttle mechanism) 53a-53c N2 gas pressure adjusting branch (gas pressure adjusting branch) 54a-54c first through third (Opening / closing means) 60 circulation line 61 opening / closing valve 62 circulation pump 63 temperature adjusting mechanism 64 filter 65 valve

Continuation of the front page (56) References JP-A-8-10673 (JP, A) JP-A-9-199467 (JP, A) JP-A-10-326765 (JP, A) JP-A-6-151403 (JP) , A) (58) Field surveyed (Int. Cl. ⁷ , DB name) H01L 21/304 B08B 3/04 B08B 3/08

Claims (9)

(57) [Claims] 1. A cleaning tank for storing a cleaning liquid and immersing an object in the cleaning liquid to clean the surface thereof, a cleaning liquid supply pipe connecting the cleaning tank and a pure water supply source, and storing a chemical liquid. A chemical solution storage container; a chemical solution supply tube connecting the cleaning solution supply tube and the chemical solution storage container via opening / closing switching means; and a gas supply device for supplying a gas for transporting the chemical solution into the chemical solution storage container. The gas supply means, a gas supply pipe connecting the gas storage source and the gas supply source, a gas pressure adjusting means interposed, and the drug storage vessel, with a liquid level detection means attached,
Based on the detection signal from the liquid level detector,
A cleaning treatment apparatus characterized in that the chemical solution is always kept constant . 2. A cleaning tank for storing a cleaning liquid and immersing an object in the cleaning liquid to wash the surface thereof, a cleaning liquid supply pipe connecting the cleaning tank and a pure water supply source, and storing a chemical liquid. A chemical solution storage container, a chemical solution supply tube connecting the cleaning solution supply tube and the chemical solution storage container via opening / closing switching means, a gas supply device for supplying a chemical solution transport gas into the chemical solution storage container, and the cleaning solution supply tube And a pure water flow rate detecting means for detecting a flow rate of pure water flowing through the cleaning liquid supply pipe, wherein the gas supply means connects the chemical solution storage container to a gas supply source. A cleaning apparatus, wherein a gas pressure adjusting means is provided in a pipe, and the gas pressure adjusting means is controlled based on a detection signal detected by the pure water flow rate detecting means. 3. The cleaning apparatus according to claim 1, wherein the chemical liquid transporting gas is an inert gas. 4. The cleaning apparatus according to claim 1, wherein the cleaning tank includes an inner tank for immersing an object to be processed and an outer tank for covering an outer edge of an opening of the inner tank. The bottom of the outer tank and the cleaning liquid supply unit disposed in the inner tank are connected by a circulation pipe, and a circulation pump, a temperature adjusting means, and a filter are provided in the circulation pipe. A cleaning treatment apparatus, comprising: 5. The cleaning apparatus according to claim 1, wherein a gas adjusting branch including a plurality of opening / closing means and a throttle mechanism is provided in the gas supply pipe of the gas supply means. Characterized by being formed so as to be selectively opened and closed. 6. The cleaning apparatus according to claim 2 , wherein a liquid level detecting means is attached to the chemical storage container,
A cleaning treatment apparatus characterized in that a chemical solution in a chemical solution storage container is always kept constant based on a detection signal from a liquid level detecting means. 7. The cleaning apparatus according to claim 1, wherein the chemical solution storage container is formed by a tank having a circular section having a height at least equal to or less than a diameter. Characteristic cleaning equipment. 8. A cleaning method for immersing an object to be processed in a cleaning liquid stored in a cleaning tank to wash the surface of the object to be processed, comprising: A first cleaning treatment step of overflowing a chemical solution diluted to a concentration to wash the object to be processed, and when the diluted chemical solution reaches a predetermined concentration, the supply of both the pure water and the chemical solution is stopped. A second cleaning process step of adjusting the temperature of the diluent in the cleaning tank to a predetermined temperature and circulating the diluted liquid to wash the object; and causing pure water to overflow in the cleaning tank and adhere to the object. A third cleaning treatment step of washing the chemical solution. 9. A cleaning method for immersing a processing object in a cleaning liquid stored in a cleaning tank to wash the surface of the processing object, wherein the cleaning tank is used to clean the processing object by overflowing pure water. A first cleaning step of performing, a second cleaning step of cleaning the object by overflowing a chemical solution diluted to a predetermined concentration into the pure water continuously supplied in the cleaning tank, When the concentration reaches a predetermined concentration, the supply of both the pure water and the chemical is stopped, and the diluted chemical in the cleaning tank is adjusted to a predetermined temperature and circulated to clean the object to be processed. A cleaning method, comprising: three cleaning steps; and a fourth cleaning step of cleaning a chemical solution attached to the object by overflowing pure water in the cleaning tank.