JP2002118085A - Substrate-treating method and apparatus therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a substrate-treating method and a substrate-treating apparatus which obtains the same cleaning effect as in the prior art, without requiring the use of sulfuric acid, hydrogen peroxide, ammonia, oxygen plasma, etc., and without producing harmful vapors, mixing ferric components, damaging the substrate or bringing about environment load, etc. SOLUTION: The substrate-treating method is a method of removing organic compounds on a substrate, comprising a step of treating the substrate with water prepared by dissolving an ozone-containing gas in ultrapure water, and a step of treating the substrate with water prepared by dissolving a hydrogen- containing gas in ultrapure water, and continuously executing these steps; or a method of removing organic compounds on the substrate, comprising a step of treating the substrate with water prepared by dissolving an ozone-containing gas and hydrogen-containing water in ultrapure water or mixing the ozone- containing water with hydrogen-containing water, or a step of treating the substrate with the ozone-containing water and the hydrogen-containing water at the same time. The treating apparatus executes the treating method.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of forming a structure (pattern) such as a circuit on various substrates such as a wafer for forming a semiconductor element, a glass substrate, a ceramic substrate and the like, and then removing an organic substance remaining on the substrate. The present invention relates to a substrate processing method and a substrate processing apparatus for cleaning and removing foreign matter and other foreign matter attached during or after structure formation.

[0002]

2. Description of the Related Art When a structure such as a fine electrical element or a circuit is formed on a substrate, an organic material such as a photoresist (hereinafter referred to as a resist) is applied, exposed, developed, and the like on the substrate.
The above-described structure is formed by forming an arbitrary resist pattern and performing processing such as etching on the substrate surface. After performing this process, unnecessary resist on the substrate is removed.

After the removal of the resist, it is necessary to wash and remove fine pieces of the resist remaining on the substrate and other foreign substances adhered during or after the formation of the structure from the substrate. Conventionally, this cleaning method is classified into a wet method and a dry method according to the type and condition of a resist or an element forming process.

[0004] In the wet method, a chemical solution having oxidizing power containing sulfuric acid, hydrogen peroxide solution or the like as a main component is often used (SPM treatment). On the other hand, in the dry method, organic substances and the like on a substrate are removed by oxidative decomposition (ashing) using oxygen as a main process gas. Further, depending on the state of contamination of the substrate, a cleaning process using an appropriate combination of an ashing process using oxygen plasma, an SPM process, and a chemical solution process (APM process) containing ammonia and hydrogen peroxide as main components is performed.

[0005]

In the above conventional method, when the treatment is performed by a wet method, sulfuric acid, hydrogen peroxide,
Since chemicals such as ammonia are used, sulfuric acid vapor that has an adverse effect on the substrate, such as corrosion, may be generated. After these treatments, there is a problem that a large amount of washing water is required and the environmental load due to drainage is large. In addition, when oxygen plasma is used in a dry method, the plasma is in a high energy state, and there is a problem that a chemically sensitive substrate and a structure formed on the substrate may be significantly damaged.

Accordingly, an object of the present invention is to obviate the use of sulfuric acid, hydrogen peroxide, ammonia, oxygen plasma, etc., without generating harmful vapors, mixing in iron, damaging substrates, and causing environmental load. An object of the present invention is to provide a substrate processing method and a processing apparatus which can provide a cleaning effect similar to that of the related art.

[0007]

The above object is achieved by the present invention described below. That is, the present invention relates to a method for removing organic substances present on a substrate, comprising a step of treating the substrate with water in which a gas containing ozone is dissolved in ultrapure water (hereinafter referred to as ozone water), and a method for removing hydrogen. A step of treating the substrate with water (hereinafter referred to as hydrogen water) in which a gas is dissolved in ultrapure water, wherein these steps are performed continuously; removing organic substances present on the substrate. A method in which a substrate is dissolved in water in which an ozone-containing gas and a hydrogen-containing gas are dissolved in ultrapure water, or water in which ozone water and hydrogen water are mixed (hereinafter, both are collectively referred to as mixed water). A substrate processing method comprising a step of performing processing or simultaneously processing a substrate with ozone water and hydrogen water; and a processing apparatus for performing these methods.

[0008]

Next, the present invention will be described in more detail with reference to preferred embodiments. The substrate to be treated by the method of the present invention includes, for example, various substrates such as a glass substrate, a substrate made of silicon or a crystal of a metal compound, and is not particularly limited. The main object of the present invention is a substrate on which a pattern has been formed and which has undergone a resist removal step.

That is, various patterns are formed on a substrate by using a resist by pattern exposure, development, baking, etching, resist stripping, and the like. However, the resist is not completely removed from the substrate in resist stripping. , Fine resist pieces remain on the substrate, or fine resist pieces once peeled off adhere to the substrate,
Further, in the above process, various kinds of fine foreign substances are often attached to the substrate. The present invention is particularly useful for cleaning such substrates.

Further, when injected a large amount of ions in the resist, e.g., 1 cm to when injected ² per 10 ^{1 5} or more ions, the dry to remove the remaining resist (resist stripping after remaining resist strip) Although the method uses oxygen plasma or the like, when the ion implantation amount is about 10 ¹³ , the method of the present invention can sufficiently remove the residual resist. In the element manufacturing process, it is particularly useful for removing a residual resist having an ion implantation amount of 10 ¹³ or less.

The ozone water used in the present invention is obtained by dissolving a gas containing ozone in ultrapure water, and the ozone water must have an ozone concentration of 10 ppm or more.
Preferably, the concentration is 50 to 100 ppm. If the ozone concentration is less than 10 ppm, oxidative decomposition of organic substances such as resist pieces attached to the substrate is insufficient. The higher the ozone concentration, the better, and may exceed 100 ppm. Such ozone water can be easily obtained by bringing a gas containing ozone generated from a known ozone generator into contact with ultrapure water. The ozone water is, besides ozone,
In order to maintain the concentration of ozone, it may contain carbon dioxide, ammonium carbonate, acetic acid or formic acid.

The rate of application of the ozone water to the substrate to be processed is 1 ml / min or more, preferably 1 to 10 ml / min per 1 cm ² of the substrate area. Application speed 1m
If it is less than 1 / min, the ozone water may not reach the entire surface of the substrate, and the oxidative decomposition of organic substances such as resist pieces attached to the substrate is insufficient. 1ml / mi
If n or more, a liquid film is formed on the entire surface of the substrate to be processed, and organic substances are sufficiently decomposed. The application speed is 10 ml / m
Beyond "in", there is no special benefit, only the cost increases.

By applying ozone water to the substrate to be processed as described above, organic substances such as fine resist pieces adhering to the substrate are oxidized and decomposed, and the organic substances oxidized by the subsequent treatment with hydrogen water. Is quickly washed away. When the amount of organic substances such as resist pieces is large or the amount of ion implantation into the resist is large, the above treatment with ozone water may be performed twice or more continuously.

In the treatment with ozone water, the substrate or the processing atmosphere can be heated to promote the oxidation treatment with ozone water. Heating temperature is over 30 ℃,
The temperature is preferably 60 ° C. or higher, and such heating may be performed by any method. For example, heating can be performed by introducing heated ultrapure water or heated nitrogen gas into the processing system.

The hydrogen water used in the present invention is obtained by bringing a gas containing hydrogen generated by a known hydrogen generator into contact with ultrapure water by a known method. The hydrogen concentration of the hydrogen water is 0.5
ppm or more, preferably 1.0 to 1.6 ppm.
If the hydrogen concentration is less than 0.5 ppm, sufficient removal of foreign substances cannot be expected, which is insufficient. On the other hand, when the hydrogen concentration is 1.6 pp
If it exceeds m, hydrogen gas is desorbed under atmospheric pressure, which is dangerous, and bubbles are generated, resulting in a significant decrease in cleaning efficiency, which is not preferable.

The rate of applying the hydrogen water to the substrate to be treated is 1 ml / min or more, preferably 1 to 10 ml / min per 1 cm ² of the substrate area. Application speed is 1ml
If it is less than / min, the hydrogen water may not spread over the entire surface of the substrate, and the effect of cleaning ozone oxide of organic substances and other foreign substances adhering to the substrate is insufficient. 1m
If it is 1 / min or more, a liquid film of hydrogen water is formed on the entire surface of the substrate to be processed, and the ozone oxide and other foreign substances are sufficiently washed. Further, even if the application speed exceeds 10 ml / min, there is no special advantage only in the increase in cost.

Each of the above treatment with ozone water and treatment with hydrogen water may be repeated a plurality of times according to the degree of contamination of the substrate. In addition, the order of the treatment with the ozone water and the hydrogen water is preferably such that the treatment with the ozone water is performed first, and then the treatment with the hydrogen water is performed, or vice versa. Further, the treatment with ozone water and the treatment with hydrogen water may be performed alternately.

Further, in the present invention, the treatment with ozone water and the treatment with hydrogen water may be performed simultaneously. Further, the substrate may be treated with a mixed solution (A) obtained by mixing the ozone water and the hydrogen water at an appropriate ratio, or a treatment in which a gas containing ozone and a gas containing hydrogen are dissolved in ultrapure water. Liquid (B)
(Hereinafter A and B are collectively referred to as mixed water). Further, a treatment with ozone water or hydrogen water may be added before and after the treatment with the mixed water. In each case, the ozone concentration or hydrogen concentration of ozone water, hydrogen water or mixed water to be used, the rate of applying these liquids to the substrate, and the heating of the substrate may be the same as described above.

As described above, by treating the substrate with ozone water and hydrogen water or a mixture of water, oxides and other foreign substances, such as fine resist pieces, adhering to the substrate are promptly washed and removed. In particular, in the treatment with hydrogen water or the treatment with the mixed water, the cleaning effect of the substrate is further promoted by activating the hydrogen by irradiating the hydrogen water or the mixed water with ultrasonic waves. The ultrasonic treatment may be performed by a usual method, and is not particularly limited. The frequency of the ultrasonic wave is 0.5 MHz.
z or more, preferably 1 MHz or more. The ozone water may be irradiated with ultrasonic waves.

The above treatment of the substrate with ozone water, hydrogen water or mixed water is preferably performed while the substrate to be processed is horizontally rotated, and the number of rotations of the substrate to be processed is 500 rpm.
m or more, preferably 1000 to 3000 rpm.
When the number of rotations of the substrate is less than 500 rpm, the treatment liquid is insufficiently replaced on the substrate by centrifugal force, and spin-out of the removed foreign matter is insufficient.
If it exceeds rpm, it is not preferable because the substrate is spin-dried and it becomes difficult to form a necessary liquid film on the substrate surface.

The above treatment of the substrate with ozone water, hydrogen water or mixed water is hermetically sealed and insulated from the outside world in order to avoid ozone being a toxic gas and contamination of dust from the outside. It is preferable to carry out in an atmosphere set. After the processing, ozone remaining in the processing area can be easily rendered harmless by thermal decomposition or ultraviolet irradiation.

In the present invention, although not essential,
As necessary, before any of the steps of treating the substrate with ozone water, hydrogen water, or mixed water, the organic substances adhering to the substrate are ashed using an oxidizing gas such as ozone gas or oxygen gas. The effects of the present invention can be further enhanced by treating the substrate, washing the substrate with an organic solvent before the above step, or treating the substrate with water containing hydrogen fluoride after the above step.

Next, the processing apparatus of the present invention will be described.
As shown in FIG. 1, a processing apparatus for carrying out the method of the present invention is provided with a processing tank 1, a substrate holder 2 that rotates horizontally in the processing tank, and an upper part of the processing tank. It has a nozzle 3 for discharging liquid, a conduit 4 for supplying liquid to the nozzle, and a chamber 5 for closing the whole, wherein the nozzle 3 has a length equal to or larger than the diameter of the substrate 9 and a width smaller than the diameter of the substrate 9. It is characterized by having a rod shape. In addition, a motor 6 for rotating the substrate holder 2, other necessary chemicals, for example, an acid such as ultrapure water, hydrochloric acid, sulfuric acid, and hydrogen fluoride, an alkaline solution such as ammonia, carbon dioxide,
Conduit 7 for supplying nitrogen gas, carboxylic acid compound, etc.
It has a drain 8 for discharging the liquid collected in the processing layer 1 and the like.

In the apparatus shown in FIG. 1, one or a plurality of substrates 9 are placed on the substrate holder 2 by an appropriate means, for example, a chuck type such as a vacuum type or a side support type. As described above, after pre-processing the substrate as necessary, ozone water, hydrogen water or mixed water is supplied to the horizontally rotating substrate in a series of steps to wash the substrate. After the substrate is washed, the substrate is rinsed with ultrapure water as needed, the rotation speed of the substrate holder 2 is increased, and the liquid adhering to the substrate is dried and removed by a so-called spin dry method.
A cleaned substrate is obtained.

When the substrate is treated with the mixed water,
An aqueous solution (mixed water) is prepared by mixing the ozone water and the hydrogen water at a predetermined ratio, or dissolving a gas containing ozone and a gas containing hydrogen at a predetermined concentration in ultrapure water, The mixed water may be supplied to and discharged from the nozzle 3 through any of the illustrated paths. In the case where the substrate is simultaneously treated with ozone water and hydrogen water, the supply amounts of the ozone water and hydrogen water are controlled at a predetermined ratio, sent to the nozzle 3, and discharged simultaneously to the substrate 9. Good.

The above-described apparatus of the present invention is particularly characterized by the configuration of the nozzle. One example is shown in FIG. FIG.
FIG. 4 is a perspective view, a side view, and a front view of the nozzle. The length of the nozzle is substantially the same as or longer than the diameter of the substrate, and the width is smaller than the diameter of the substrate, and the nozzle is in a bar shape. In the example shown in the figure, a partition 21 is formed of a cell 21 to which ozone water or mixed water is supplied and a cell 22 to which hydrogen water or mixed water is supplied, and a conduit 24 for supplying each liquid to each cell. Are provided, and a discharge port 25 for discharging a liquid is provided at a lower portion, respectively. As described above, the flow path of ozone water, hydrogen water or mixed water is divided into a large number of cells, and ozone water, hydrogen water or mixed water is supplied to each cell and discharged from each discharge port. Uniform discharge of hydrogen water or mixed water becomes possible.

Each cell 2 for discharging ozone water or mixed water
1, and each cell 22 for discharging hydrogen water or mixed water is provided with a quartz rod 26 which is an ultrasonic generator penetrating the cell in the longitudinal direction, and is provided with ozone water, hydrogen water or mixed water, respectively. Ultrasonic waves are applied.
It is desirable to sonicate hydrogen water or mixed water,
Since the ultrasonic irradiation of the ozone water is not essential, the quartz rod 26 may not be provided in the cell of the ozone water. An amplifier is connected to the quartz rod 26 so as to vibrate the quartz rod 26 to generate ultrasonic waves.

Ultrasonic treatment of only hydrogen water or mixed water,
It is preferable that a shock absorber 27 as an ultrasonic shielding plate is provided between the ozone water cell 21 and the hydrogen water or mixed water cell 22 in preparation for a case where ozone water is not subjected to ultrasonic treatment. By supplying ozone water, hydrogen water or mixed water to the substrate surface using the nozzle having the above configuration, since the substrate itself is rotating at high speed, the ozone water, hydrogen water or mixed water is applied to the substrate surface. The substrate is evenly sprayed and the substrate is uniformly cleaned.

[0029]

Next, the present invention will be described more specifically with reference to examples and comparative examples. The following Examples and Comparative Examples are merely examples, and do not limit the present invention in any way. It should also be understood that the preferred processing conditions change with increasing or decreasing the amount of contaminants adhering to the substrate, and that it is not the purpose of the present invention merely to remove the residual resist. In the method of the present invention, it is expected that the effect can be expected with respect to the substrate contaminated with organic matter and the overall removal of foreign matter caused by organic matter,
The following example should be understood. Further, according to the present invention, the substrate after being processed by the method of the present invention,
The high cleanliness of the surface also suggests that the characteristics of the structure (pattern) formed there are improved. In the following, SPM (treatment) refers to sulfuric acid (concentration of 96
APM (treatment) means ammonia water (concentration 28% by weight), hydrogen peroxide solution (concentration 30% by weight), and hydrogen peroxide (concentration 30% by weight). , And these treatment solutions are appropriately diluted with ultrapure water before use.

Reference Example 1 (Preparation of Sample) An 8-inch CZSi wafer (hereinafter, referred to as a substrate) was subjected to APM treatment (ammonia: hydrogen peroxide solution: ultra pure water = 1: 1: 8) by a wet immersion type washing apparatus, 70 ° C, ultrasonic treatment). After drying the treated substrate, an I-ray photosensitive resist was applied to the substrate by a single-wafer spin coater, and the entire surface was exposed to I-ray to expose the resist and baked. Thereafter, BF ₂ or As was ion-implanted. The doping amount of BF ₂ is 5.0E13 atoms / cm ² (acceleration voltage: 15 ke
V) was designated as sample A, and the doping amount of As was 8.0.
Sample B was E13 atoms / cm ² (acceleration voltage: 30 keV), and sample C was not doped. Table 1 below shows the sample preparation conditions. The resist film thickness of each sample was measured by a light interference type film thickness measuring device.

[0031]

Example 1 (Processing of Samples) For each sample, the resist was stripped off with ozone water, and after the stripping, the resist was washed using ozone water, hydrogen water or mixed water (sequence processing 1). ~
3) was used. In the processing, using the apparatus shown in FIG. 1, the processing from resist stripping, cleaning and subsequent drying up to drying was collectively performed in the same apparatus and the same processing chamber. Table 2 below shows combinations of the sequence processing of each sample. Note that reference processing 1 is a comparative example.

[0033]

Sequence processing 1 : Resist stripping treatment with ozone water : Ozone water for treating each sample was discharged from the nozzle shown in FIG. Table 3 below shows the processing conditions in this processing step. Also,
The resist film thickness before and after the processing is also shown. The discharge amount of the ozone water at this time is 10 ml / min per 1 cm ² of the substrate area. Ultrapure water heated to 50 ° C. by a quartz heater was discharged to the substrate from a discharge port different from the discharge port of the ozone water, and ozone water was further discharged at the same discharge rate from above.

[0035]

[0036]Oxidative decomposition by ozone water after resist stripping
processing: Laser light source on substrate after resist stripping
Observation with a microscope was performed. Residual resist film on substrate surface
No residue was found, but some resist pieces and relatively large
Foreign matter remained. These foreign substances are carbon and silicon
It is a foreign substance mainly composed of corn oxide. Resist
Foreign matter remaining on the substrate immediately after peeling peaks at about 3 μm
Particle size distribution. Therefore, these foreign substances are oxidized
Since it is easily oxidized and decomposed with strong ozone water, ozone
The foreign matter was oxidatively decomposed by water. Oxidative decomposition treatment
Was carried out by discharging ozone water from the nozzle shown in FIG.
Foreign matter measurement before and after processing is performed by laser light scattering foreign matter counter
I went in. Processing conditions and results of each sample at this time
Are shown in Table 4 below. Ozone water flows from the nozzle to the substrate area 1
cm ^Two10 ml / min.

[0037]

Hydrogen water after oxidative decomposition treatment with ozone water
Cleaning treatment : Hydrogen water was discharged from a nozzle having an ultrasonic oscillator shown in FIG. 2 to process each sample. The frequency of the ultrasonic wave at this time is 1.5 MHz. The measurement of foreign matter before and after the treatment was performed by a laser light scattering type foreign matter counter.
A review with a microscope before the processing showed that almost no resist pieces were found, and only minute foreign matters remained. In addition, the particle size distribution of the foreign matter shifted from 3 μm to about 1 μm, indicating that the relatively large foreign matter remaining after the resist was stripped was oxidized and decomposed. OR of hydrogen water
The P value is about -550 mV, and the particles and the surface potential on the substrate are charged to the same negative, so that foreign matter is removed by electrostatic repulsion. In addition, foreign substances are physically removed by the effect of cavitation by ultrasonic waves, and radicals such as hydrogen and hydroxy are generated. After this processing step, spin drying was performed at 3000 rpm in a nitrogen stream. All of the samples after the treatment were well washed.

[0039]

Sequence process 2 Resist stripping process by SPM process : The SPM process for processing the sample was performed by a general chemical bath cleaning apparatus. The processing conditions in this processing step are shown in Table 6 below.
Shown in Also, the resist film thickness before and after the processing is shown.

The substrate after the removal of the resist was observed under a microscope using a laser light source. No resist film remained on the substrate surface. The foreign matter remaining on the substrate immediately after the resist was stripped had a particle size distribution having a peak at about 1 μm. The next oxidative decomposition step with ozone water was started.

Oxidative decomposition by ozone water after resist stripping
Treatment : The substrate after resist removal was observed with a laser light source microscope. No residue of the resist film was confirmed on the substrate surface, but some resist pieces and relatively large foreign matters remained. These foreign substances are foreign substances containing carbon or silicon oxide as a main component. Foreign matter remaining on the substrate immediately after the resist was stripped had a particle size distribution having a peak at about 0.5 μm. Therefore, since these foreign substances are easily oxidized and decomposed by oxidizing ozone water, oxidative decomposition treatment with ozone water was performed. The process was performed by discharging ozone water from the nozzle shown in FIG. The measurement of foreign matter before and after the treatment was performed by a laser light scattering type foreign matter counter. Table 7 shows the processing conditions and results of each sample at this time. Ozone water is supplied from the nozzle at a rate of 10 ml / m per 1 cm ^{2 of} substrate area.
Discharged in.

[0043]

Hydrogen water after oxidative decomposition treatment with ozone water
Cleaning treatment by : Hydrogen water was discharged from a nozzle having an ultrasonic oscillator shown in FIG. 2 to process each sample. The frequency of the ultrasonic wave at this time is 1.5 MHz. Table 8 below shows the processing conditions and results of each sample. The measurement of foreign matter before and after the treatment was performed by a laser light scattering type foreign matter counter. A review with a microscope before processing showed that only minute foreign matters remained. After this processing step, spin drying was performed at 3000 rpm in a nitrogen stream. All of the samples after the treatment were well washed, indicating that this example gave results comparable to those of the conventional treatment, suggesting that the sample could be substituted for the conventional treatment.

[0045]

Sequence processing 3 Resist stripping processing by SPM processing : The SPM processing for processing the sample was performed by a general chemical bath cleaning apparatus. The processing conditions in this processing step are shown in Table 9 below.
Shown in Also, the resist film thickness before and after the processing is shown.

[0047]

The substrate after the removal of the resist was observed with a laser light source under a microscope. Almost no large foreign matter was found on the substrate surface, but the adhesion of the foreign matter was extremely large depending on the sample. This seems to be a phenomenon caused by deterioration of the SPM. After this peeling treatment, the treated substrate was immersed in ultrapure water for 5 minutes to rinse off the SPM, and dried by spin drying.

Hydrogen to which ozone water has been added after stripping the resist
Cleaning treatment with water (mixed water) : After the above-described SPM treatment, the substrate was treated with a mixed water obtained by adding ozone water to hydrogen water (1.5 ppm). The concentration of the ozone water added at this time is 60 ppm. The ozone concentration at this time should be selected according to the degree of contamination of the foreign matter to be removed.In this example, the concentration is set as described above because the degree of contamination is high in addition to the fact that the contaminants are mainly organic substances. ing. In the processing of the substrate, mixed water was discharged at a rate of 3 ml / min per 1 cm ² of the substrate area, and discharged from a nozzle having an ultrasonic oscillator shown in FIG. The frequency of the ultrasonic wave at this time is 1.5 MHz. Table 10 below shows the processing conditions and results of each sample. The measurement of foreign matter before and after the treatment was performed by a laser light scattering type foreign matter counter. A review with a microscope before the processing showed that almost no resist pieces were found, and only minute foreign matters remained. In addition, the particle size distribution of the foreign matter has shifted from 3 μm to about 1 μm, indicating that the relatively large foreign matter remaining after the resist was stripped was oxidized and decomposed. Hydrogen water alone has an ORP value of about -550 mV, and the surface potential on the particles and the substrate is negatively charged, so that the oxide is removed by electrostatic repulsion. In addition, foreign substances are physically removed by the effect of cavitation by ultrasonic waves, and radicals such as hydrogen and hydroxy are generated. After this processing step, spin drying was performed at 3000 rpm in a nitrogen stream. All of the samples after the treatment were well washed.

[0050]

From the above results, it has been shown that treatment with ozone water and hydrogen water or a mixed water is particularly effective for removing foreign matter after the resist is stripped. In addition, although this example is performed in a single-wafer apparatus, it does not involve removal of a large amount of organic substances such as a resist, and in the case of only removing these foreign substances, a immersion type using hydrogen water, ozone water or mixed water is used. Even if the processing is performed, substantially the same effect can be obtained. Therefore, the present invention is useful regardless of the mode of the apparatus in terms of removing foreign substances.

Comparative Example 1 (Reference Process 1) Resist stripping process by SPM: Table 11 shows the conditions of the resist stripping process by SPM. Also, the resist film thickness before and after the processing is shown. The treatment was performed with a chemical immersion type apparatus. The resist was all stripped.

[0053]

A review with a microscope revealed that no large foreign matter was found, but that the amount of foreign matter attached was very large depending on the sample. This seems to be a phenomenon caused by deterioration of the SPM. After this cleaning treatment, the treated substrate was immersed in ultrapure water for 5 minutes to rinse off the SPM, dried by spin drying, and then cleaned by APM.

APM after resist stripping process by SPM
Cleaning treatment : Each sample was immersed in a chemical immersion type cleaning device having a vibrator at the lower part of the cleaning tank to perform the treatment. The frequency of the ultrasonic wave at this time is 1.5 MHz. The measurement of foreign matter before and after the treatment was performed by a laser light scattering type foreign matter counter. The processing conditions and results are shown in Table 12 below.
Most of the remaining foreign matter was removed.

[0056]

The fact that the above-described embodiment gave results comparable to the conventional processing of the comparative example proves that the processing sequence of the present invention can withstand the substitution of the conventional processing. Has been proved to be particularly useful.

[0058]

According to the method of the present invention, in a process for removing unnecessary resist after forming a semiconductor device structure,
Since only ozone water, hydrogen water or mixed water is used, it is a low cost method that has a small environmental load and does not damage the element structure. The method of the present invention minimizes the deterioration of the electrical characteristics of the element due to corrosion and can expect an improvement in the product yield, so that the running cost of the semiconductor manufacturing apparatus can be reduced and the safety can be improved. As described above, a series of processes in the cleaning process after stripping the resist using ozone water, hydrogen water, or mixed water will reduce various environmental burdens and simplify the element formation process, thereby solving various problems in the future manufacturing industry such as energy saving. Can also be adapted.

Heretofore, foreign substances such as residual resist existing on the substrate have been removed using sulfuric acid, ammonia, hydrogen peroxide, an organic solvent, or the like. The method of the present invention comprises:
Since these chemicals are not used, the structure of the semiconductor element and the wiring material are not significantly corroded, thereby reducing damage to the element structure, for example, improving the reliability of the element performance,
This leads to a reduction in the cost of a material used for a process or a process for preventing corrosion, and a reduction in corrosion of a wiring material leads to a reduction in electric resistance of the element, a reduction in power consumption, and an increase in element performance.

It is said that the conventional treatment using activated hydrogen water is capable of removing minute foreign substances. However, the method of the present invention employs hydrogen water instead of the above-described treatment with ozone water. By combining treatments or using mixed water, the process from the removal of the resist, such as the resist, to the subsequent cleaning can be performed collectively without using a high-purity conventional chemical solution, such as sulfuric acid. It is significant that the method can be performed, and the processing can be performed for the first time by using the method and the apparatus of the present invention which enabled the processing.

According to the present invention, the steps of resist stripping and cleaning can be performed collectively as described above, so that it is not necessary to carry the substrate for each processing step, and it is possible to reduce the chance of contact with a dangerous chemical solution. Benefits such as reduced chance of contact with pollutants are generated. The advantage is that this batch processing can contribute to cost reduction and the like.

[Brief description of the drawings]

FIG. 1 is a schematic diagram of a processing apparatus of the present invention.

FIG. 2 is a diagram illustrating the structure of a nozzle.

[Explanation of symbols]

 1: Treatment tank 2: Substrate holder 3: Nozzle 4: Conduit 5: Chamber 6: Motor 7: Conduit 8: Drain 9: Substrate 21, 22: Cell 23: Partition 24: Conduit 25: Discharge port 26: Quartz rod 27 :shock absorber

Claims (20)

[Claims] 1. A method for removing an organic substance present on a substrate, comprising: treating a substrate with water in which an ozone-containing gas is dissolved in ultrapure water (hereinafter referred to as ozone water); Dissolved in ultrapure water (hereinafter referred to as hydrogen water)
And a step of processing the substrate by the method, wherein these steps are continuously performed. 2. A method for removing organic substances present on a substrate, comprising: dissolving an ozone-containing gas and a hydrogen-containing gas in ultrapure water; or a mixture of ozone water and hydrogen water. (Hereinafter referred to as "mixed water"), or a method for treating a substrate simultaneously with ozone water and hydrogen water. 3. The substrate processing method according to claim 1, wherein the substrate to be processed is a glass substrate or a substrate made of a crystal of silicon or a metal compound. 4. The substrate processing method according to claim 1, wherein the substrate to be processed is a substrate contaminated with an organic substance or an organic substance into which ions have been implanted. 5. The substrate processing method according to claim 1, wherein the substrate to be processed is a substrate contaminated with an organic substance attached in a semiconductor element manufacturing process. 6. The substrate processing method according to claim 1, wherein the ozone concentration of the ozone water is 10 ppm or more. 7. The substrate processing method according to claim 1, wherein the hydrogen concentration of the hydrogen water is 0.5 ppm or more. 8. The application rate of ozone water or mixed water to a substrate to be treated is 1 ml / m ² per 1 cm ^{2 of} substrate area.
The substrate processing method according to claim 1, wherein the value is at least in. 9. The method according to claim 1, wherein the hydrogen water or the mixed water is activated by ultrasonic treatment and applied to the substrate to be processed.
4. The substrate processing method according to 1. 10. The substrate processing method according to claim 1, wherein the processing is performed while horizontally rotating the substrate to be processed. 11. The rotation speed of a substrate to be processed is 500 rpm.
The substrate processing method according to claim 10, which is as described above. 12. The substrate processing method according to claim 1, wherein the processing is performed in the same processing apparatus. 13. The substrate processing method according to claim 1, wherein the processing is performed by heating the substrate to be heated to 30 ° C. or higher. 14. The substrate processing method according to claim 13, wherein the heating is performed by introducing heated ultrapure water or heated nitrogen. 15. The substrate processing according to claim 1, wherein an organic substance is ashed using an oxidizing gas before any of the steps of processing the substrate with ozone water, hydrogen water, or mixed water. Method. 16. The substrate processing method according to claim 1, wherein the substrate is washed with an organic solvent before any of the steps of processing the substrate with ozone water, hydrogen water, or mixed water. 17. The substrate processing method according to claim 1, wherein the substrate is treated with water containing hydrogen fluoride after any one of the steps of treating the substrate with ozone water, hydrogen water, or mixed water. . 18. A processing tank, a substrate holder horizontally rotating in the processing tank, a nozzle provided at an upper portion of the processing tank and supplying liquid downward, a conduit for supplying liquid to the nozzle, And a chamber for closing the nozzle, wherein the nozzle has a rod shape having a length equal to or longer than the diameter of the substrate and a width smaller than the diameter of the substrate. 19. The processing apparatus according to claim 18, wherein an ultrasonic generator is provided in the nozzle. 20. The process according to claim 19, wherein the nozzle has a flow path of ozone water, a flow path of hydrogen water, or a flow path of mixed water, and these flow paths are shielded from ultrasonic waves. apparatus.