JPH0722373A - Chemical treatment equipment - Google Patents

Abstract

PURPOSE:To clean the surface of a specimen by a method wherein the specimen is subjected to a chemical treatment, rinsed, and centrifugally dried out, and then treated in a chamber controlled in both temperature and humidity or a vacuum chamber. CONSTITUTION:Substrates 19 placed on a loader 17 are treated with chemicals in treatment tanks 11 and 12 filled with mixed liquid of sulfuric acid and hydrogen peroxide. Then, the substrates 19 are rinsed in rinsing tanks 13 and 14. Moisture attached to the surfaces of the substrates 19 is removed by a substrate centrifugal rotary machine 15. Thereafter, the substrates 19 are thermally treated in a chamber controlled in temperature and humidity so as to accelerating the production of sulfide. Thereafter, the substrates 19 are rinsed in the rinsing tanks 13 and 14, moisture attached to the surfaces of the substrates 19 is removed by the substrate centrifugal rotary machine 15, and the substrates 19 are recovered by an unloader 18. Or, after a chemical treatment, a rinsing treatment, and a centrifugal drying treatment are carried out, moisture attached to the substrates 19 is removed in a vacuum chamber 16b by vacuum suction. By this setup, sulfide can be restrained from being produced later.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a chemical liquid processing apparatus, for example, a chemical liquid processing apparatus for removing organic substances such as photoresist used in a semiconductor manufacturing process or the like.

[0002]

2. Description of the Related Art In recent years, chemical treatment has been used in various fields and has become essential in the semiconductor industry for peeling and cleaning various films. For example, in a semiconductor process, a photoresist is generally applied to a substrate, and a chemical treatment is generally performed when the patterned photoresist is peeled off.

FIG. 5 is a schematic view of a conventional chemical liquid processing apparatus for performing chemical liquid processing. A conventional chemical liquid processing method using this apparatus will be described with reference to the drawings. First,
After the sample placed on the loader 26, for example, the substrate 28 on which the photoresist pattern is left, is moved to the processing tanks 21 and 22 containing sulfuric acid and hydrogen peroxide solution by the robot transfer unit 20, the sample 28 is transferred by the robot. Each part is immersed in each processing tank by the section 20 and the chemical solution is processed for 10 minutes. Next, the substrate 28 is washed with water in the water washing tanks 23 and 24. Then, the substrate centrifugal rotating device 25 removes water from the surface of the substrate 28, and the unloader 27 collects the substrate 28 after the chemical treatment. From the chemical treatment tanks 21 and 22,
A series of transportations from the water washing tanks 23 and 24 to the unloader 27 are similarly performed by the robot transportation unit 20.

However, in such a conventional chemical liquid processing method, a trace amount of water and sulfur remain on the surface of the substrate 28 after cleaning, and these react with each other to form a sulfide, which serves as a nucleus. Fine particles adhere to the substrate surface.
Alternatively, there is a problem that after the chemical treatment, sulfur on the substrate surface reacts with moisture in the atmosphere to form a sulfide.

[0005]

In the conventional chemical liquid treatment,
There has been a problem that a trace amount of water and sulfur remaining on the surface of the cleaned substrate remain, or water in the atmosphere reacts with sulfur on the surface of the substrate after chemical treatment. That is, moisture and sulfur react with each other to form a sulfide, which serves as a nucleus to generate fine particles on the surface of the substrate, leading to a decrease in yield. Therefore, it is an object of the present invention to provide a chemical treatment apparatus that cleans the surface of a substrate and improves the yield.

[0006]

To achieve the above object, in the first aspect of the present invention, a treatment means for treating a sample to be washed with a chemical solution, a water washing means for washing the sample with water, and a centrifuge for centrifugally drying the sample. A chemical treatment apparatus characterized by comprising a drying device, a control chamber located at the latter stage of this centrifugal drying device for controlling the temperature and humidity of the dried sample, and a washing means at the latter stage of the control chamber. I will provide a.

In order to achieve the above object, in the second aspect of the present invention, a treatment means for treating a sample to be washed with a chemical solution, a water washing means for washing the sample with water, and a centrifugal drying device for centrifugally drying the sample, There is provided a chemical liquid processing device, characterized in that it has a vacuum chamber which is located at a subsequent stage of this centrifugal drying device and forcibly removes fine particles existing on the dried sample.

[0008]

[Function] With the conventional apparatus, the humidity is 40 to 40 at room temperature under normal processing conditions.
The fine particles on the substrate treated with the chemical solution at 45%, as shown in the curve (a) of FIG.
r) When left unattended, the number increases sharply (10 ⁴ / wafer to 10
⁵ / wafer), after which there is a tendency to increase gradually. Here, particles having a diameter of 0.2 μm or more were calculated as fine particles.

Further, FIG. 4 (b) shows that the substrate treated with the chemical solution is put into the reaction chamber, and the temperature of the reaction chamber is almost the same as room temperature.
The figure shows the change in the number of fine particles with respect to the standing time when the humidity is changed after the temperature is set to 5 ° C. It can be seen that when the humidity in the reaction chamber is 45%, the increase in the number of fine particles with respect to the initial standing time is the largest, and the number of fine particles after 120 hours has also increased.

According to a first aspect of the present invention, after treating a substrate with a chemical solution,
By setting the temperature and humidity to accelerate the generation of fine particles with sulfide as the nucleus, the reaction between sulfur and moisture remaining on the substrate is accelerated to generate fine particles at an accelerated rate, and then the fine particles are washed with water. By removing the fine particles, the increase of the fine particles on the substrate thereafter is suppressed. Therefore, as can be seen from FIG. 4 (b), the humidity in the reaction chamber is most preferably 45%, and the humidity from 30% to 90% is effective in suppressing the subsequent generation of fine particles. At a humidity of about 30%, the same effect as when the humidity was 90% was obtained.

FIG. 4A shows a change in the number of fine particles with respect to a temperature change in the reaction chamber when the humidity in the reaction chamber is set to 45%. At this time, the leaving time was 8 hours. The particles tend to increase at an accelerated rate when the temperature inside the reaction chamber exceeds 30 ° C. That is, when the temperature is set to 30 ° C. or higher, the number of fine particles can be accelerated.

FIG. 4 (c) shows the increase of fine particles with respect to the standing time when the temperature of the reaction chamber is set to 40 ° C. and the humidity is set to 45%. At this time, the formation of fine particles is saturated after about 8 hours. That is, as is clear from a comparison with FIG. 3, the number of fine particles is saturated in about 24 hours in the conventional case. Therefore, when the temperature of the reaction chamber is set to 40 ° C. and the humidity is set to 45%, about 1/3 of the conventional case is obtained. Since the formation of fine particles is saturated in the period of time, even if this substrate is washed with water and the substrate from which water is removed is left again, fine particles are hardly formed on the substrate.

In a second aspect of the present invention, after treating the substrate with a chemical solution,
The substrate is placed in a vacuum chamber and the pressure in this vacuum chamber is reduced. At this time, if the pressure is set to a high vacuum of 1 Torr or more, the moisture on the substrate can be removed, and the sulfur remaining on the substrate cannot form sulfides, thus suppressing the formation of fine particles on the substrate. be able to. Conventionally, the substrate to be processed may be dried with a negative pressure in a centrifugal dryer, but since the degree of vacuum is not sufficient, the sulfide remains. In the second aspect of the present invention, the sulfide is forcibly removed by placing the substrate in a high vacuum in the subsequent processing.

[0014]

Embodiments of the present invention will be described with reference to the drawings. Example 1 FIG. 1 (a) is a schematic view of a chemical liquid processing apparatus according to an example of the present invention. As shown in FIG. 1 (a), this apparatus includes treatment tanks 11 and 12 in which a sample 19 is set in a loader 17 and treated with a chemical solution by a robot transfer unit 10 and washing tanks 13 and 1.
4. The substrate centrifuge rotating device 15 and the temperature / humidity are automatically conveyed to the control chamber 16a, the washing tank 14, the substrate centrifuge rotating device 15, and the unloader 18 for processing.

The temperature / humidity control chamber 16a, which is a characteristic part of this embodiment, has a sample holder 31 in the reaction chamber 30 as shown in FIG. 1 (b).
A heater 32 is provided on the side surface of the reaction chamber 30, for example. Further, a humidifier 33 and a dehumidifier 34 are provided outside the reaction chamber 30 via a pipe 35. However, the heater 32 does not necessarily have to be provided in the vacuum chamber, as long as it has a structure capable of warming the reaction chamber, and the humidifier 33 and the dehumidifier 34 may be integrally formed in the reaction chamber 30. I don't care.

A chemical treatment method using the apparatus of this embodiment will be described with reference to FIG. A sample placed on the loader 17, for example, a substrate 19 on which a photoresist pattern is formed, is subjected to chemical treatment for 10 minutes each in the treatment tanks 11 and 12 containing a mixed solution of sulfuric acid and hydrogen peroxide solution. At this time, it is assumed that the treatment tanks 11 and 12 are each used at a temperature of 145 ° C., and the volume ratio of the mixed solution of sulfuric acid and hydrogen peroxide is 9: 1.

Next, the substrate 19 is washed in the washing tanks 13 and 14. Next, the substrate 19 is transferred to the substrate centrifugal rotation device 15
The water on the substrate surface is removed with. After that, the temperature
Sulfide is acceleratedly generated in the humidity control chamber 16a.

At this time, it is most desirable that the temperature in the chamber 16a is 40 ° C. and the humidity is 45% from the results shown in FIG. After that, the substrate 19 is washed again with the water washing tanks 13 and 14, the substrate surface water is removed by the substrate centrifugal rotation device 15, and the substrate 19 is recovered by the unloader 18. Loader 1
A series of transports from 7 to the unloader 18 is performed by the robot transport unit 20.

By subjecting the substrate to the chemical treatment in this embodiment, the sulfides increased after the treatment in the conventional chemical treatment method are acceleratedly generated in the temperature / humidity control chamber 16a and removed by washing with water. The generation of sulfide after that is suppressed.

The relationship between the elapsed time after the processing of the substrate processed in this embodiment and the number of fine particles on the substrate will be described with reference to FIG. The curve (a) in FIG. 3 represents the result of the chemical treatment by the conventional method, and the curve (b) represents the result of the treatment by the embodiment of the chemical treatment method of the present invention. In the case of (a), the number of fine particles rapidly increases within 24 hours, while in the case of (b), the number of fine particles hardly increases at around 10 (pieces / wafer) even after 96 hours or more. Therefore, in this embodiment, the surface of the substrate can be cleaned and the yield can be improved.

Embodiment 2 FIG. 2 (a) is a schematic view of a chemical treatment apparatus according to an embodiment of the present invention. A description of this device is given below. Note that FIG.
The same parts as those in (a) are designated by the same reference numerals, and detailed description thereof will be omitted.

As shown in FIG. 2 (a), the sample 19 is set in the loader 17 and treated by the robot transfer section 10 with the chemical solution, the rinsing tanks 13, 14, the substrate centrifugal rotating device 15, and the vacuum chamber 16b. It is configured to automatically convey and process.

Here, the vacuum chamber 16b, which is a characteristic part of this apparatus, is a vacuum chamber 4 as shown in FIG. 2 (b).
A sample holder 41 is provided inside 0, and an exhaust pump 43 is provided via a valve 42.

An embodiment of the chemical treatment method of the present invention using this apparatus will be described with reference to FIG. A sample placed on the loader 17, for example, a substrate 19 on which a titanium film has been etched using a resist as a mask is subjected to chemical treatment for 10 minutes in a treatment tank 11 containing a mixed solution of sulfuric acid and hydrogen peroxide solution.

In this chemical treatment, not only the resist but also a part of the titanium film is removed. At this time, the temperature of the treatment tank is 170 ° C., and the volume ratio of the mixed solution of sulfuric acid and hydrogen peroxide solution is 6: 1. Next, the substrate 19 is washed with the washing tanks 13 and 14. Next, the substrate centrifugal rotation device 15 removes water from the surface of the substrate 19. afterwards,
Moisture on the substrate 19 is vacuumed in the vacuum chamber 16b. At this time, the pressure in the chamber 16b is 0.3 To.
rr. Here, the pressure in the chamber 16b is set to 0.
The pressure is set to 3 Torr, but by setting it to 1 Torr or less, the number of fine particles on the substrate 19 is significantly reduced. Then, the substrate 19 is collected by the unloader 18. A series of transports from the loader 17 to the unloader 18 is performed by the robot transport unit 20.

By subjecting the substrate to the chemical treatment in this embodiment, a small amount of water remaining on the substrate in the conventional chemical treatment is removed in the vacuum chamber 16b, so that the subsequent generation of sulfide is suppressed.

Also in this example, almost the same as in Example 1, almost no increase in fine particles was observed even after a long time, as compared with the prior art. In the first and second embodiments, the temperature of the processing tanks 11 and 12 is not limited to the above temperature,
It is desirable to use in the range of up to 200 ° C. Also,
The mixing ratio of sulfuric acid and hydrogen peroxide solution is not limited to the above-mentioned mixing ratio, and it is desirable that the mixing ratio be within the range of 3: 1 to 10: 1. In addition, various modifications may be made without departing from the scope of the present invention.

[0028]

According to the present invention, a substrate having a clean surface can be obtained, and the yield can be improved.

[Brief description of drawings]

FIG. 1 is a schematic diagram of a chemical liquid processing apparatus according to an embodiment of the present invention.

FIG. 2 is a schematic view of another chemical liquid processing apparatus according to an embodiment of the present invention.

FIG. 3 is a characteristic diagram showing effects of the embodiment of the chemical liquid processing device of the present invention.

FIG. 4 is a characteristic diagram showing the effect of one embodiment of the chemical liquid processing device of the present invention.

FIG. 5 is a schematic view of a conventional chemical treatment device.

[Explanation of symbols]

10 Robot Transport Section 11
Treatment tank 12 Treatment tank 13
Washing tank 14 Washing tank 15
Substrate centrifugal rotation device 16a Temperature / humidity control chamber 16b
Vacuum chamber 17 Loader 18
Unloader 19 Sample 20
Robot transport unit 21 Processing tank 22
Treatment tank 23 Washing tank 24
Washing tank 25 Substrate centrifugal rotation device 26
Loader 27 unloader 28
Sample 30 Reaction chamber 31
Sample holder 32 Heater 33
Humidifier 34 Dehumidifier 35
Piping 40 Vacuum chamber 41
Sample holder 42 Valve 43
Exhaust pump

Claims (2)

[Claims] 1. A treatment means for treating a sample to be washed with a chemical solution, a water washing means for washing the sample with water, a centrifugal drying device for centrifugally drying the sample, and a centrifugal drying device, which is positioned after the centrifugal drying device and after the drying. 2. A chemical treatment apparatus, comprising: a control chamber for controlling the temperature and humidity of the sample, and a water washing means at the latter stage of the control chamber. 2. A treatment means for treating a sample to be cleaned with a chemical solution, a water washing means for washing the sample with water, a centrifugal drying device for centrifugally drying the sample, and a centrifugal drying device, which is located after the centrifugal drying device and after the drying. And a vacuum chamber for forcibly removing the fine particles existing on the sample.