JP2004176978A - Cleaning/air-conditioning method of air supplied to semiconductor manufacturing device and air cleaning/air-conditioning unit of semiconductor manufacturing device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To clean air supplied to a semiconductor manufacturing device and to continuously adjust a temperature and humidity of the air. <P>SOLUTION: This air cleaning/air-conditioning method adjusts the temperature and the humidity of the air by using an air-conditioning means 7 after adsorbing-removing a gaseous pollutant in the air by an adsorbing part by arranging the adsorbing part 5 in an air circulating passage for communicating with the semiconductor manufacturing device 1. This cleaning/air-conditioning method continuously adsorbs-removes the gaseous pollutant in the air by alternately repeating adsorption of the gaseous pollutant by an adsorbent in the adsorbing part and regeneration by heating of the adsorbent. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a method for purifying and air-conditioning air supplied to a semiconductor manufacturing apparatus and an air-purifying and air-conditioning unit for the semiconductor manufacturing apparatus. More specifically, the present invention relates to a high-performance semiconductor product having a fine integrated circuit pattern line width. A method for continuously supplying purified air of which temperature and humidity are controlled to the semiconductor manufacturing apparatus in order to form a clean atmosphere suitable for manufacturing, and a purification / air conditioning system for realizing such a method. It is about a unit.
[0002]
[Prior art]
2. Description of the Related Art As a method of purifying air in a clean room, a method of mainly removing fine particulate contaminants in air using, for example, a HEPA filter (high-performance filter) has been conventionally implemented. However, as the integration density of integrated circuits in semiconductor products has increased remarkably and the minimum line width of integrated circuits has been reduced to the submicron level, gaseous contaminants which have not been regarded as a problem until now have been integrated circuits. It has been clarified that the gaseous contaminants are not adversely affected, and it is required to establish a method for removing the gaseous pollutants.
[0003]
More specifically, in the exposure process, which is one of the semiconductor manufacturing processes, a basic gas such as ammonia or amines, or a gaseous contaminant such as another organic gas, is liable to be adversely affected by a fine circuit pattern. It is said that it is necessary to reduce the concentration of the gaseous contaminants to 1 ppb or less in order to form. In particular, ammonia generated from the human body has an adverse effect such as inhibiting pattern formation of a chemically amplified resist and fogging a lens used in an exposure process. Further, it has been confirmed that the organic gas contaminates the wafer base material and the substrate and lowers the productivity (yield) of the product.
[0004]
In the resist coating / developing process, which is another semiconductor manufacturing process, it is necessary to eliminate the influence caused by gaseous contaminants as in the exposure process. Particularly, in the developing step, gaseous contaminants such as ammonia and organic gas are generated from the chemical solution to be used. Therefore, it is necessary to prevent the contamination by such gaseous contaminants from spreading.
[0005]
In some cases, a semiconductor manufacturing apparatus is installed and used in a clean room. In such a case, an organic gas generated from a polymer material including a plastic is often used as a component of a clean room. Parts (eg, paints and floor coverings, sheets, panels, power cables, sealants, packing plastics, mold release materials, antioxidants, etc.) have the potential to be generated from everywhere in the clean room. In particular, when the gas in the clean room is circulated for use in order to reduce the cost of air conditioning, the organic gas is continuously generated from the polymer parts, but the organic gas is not discharged to the outside. There is a problem that the concentration of the reactive gas gradually becomes higher than the outside air.
[0006]
On the other hand, it is of course effective to clean the entire clean room in which the semiconductor manufacturing equipment is installed, but the cost increase cannot be neglected. For example, a facility such as a mini-environment or a micro-environment is provided to form a highly purified area. However, by performing work in this area, cost increases due to cleaning are also suppressed. However, also in these facilities, the generation of organic gas becomes a problem because the polymer material is frequently used similarly to the clean room.
[0007]
The gaseous pollutants which adversely affect the production of semiconductor products are classified as shown in the following (1) to (3), including the above-mentioned ammonia and organic gas, and these gaseous pollutants are removed. As a means for performing this, a chemical filter is installed in a fan filter unit (FFU) or the like in a clean room, or, in addition to the chemical filter, a high-pressure discharge unit is provided in a semiconductor manufacturing apparatus to convert a trace gas component into plasma by discharging, or to use a photocatalyst. In order to remove organic gas by using a gas nozzle or to install an atomizing nozzle to remove alkali components such as ammonia by a gas-liquid contact method (for example, Patent Document 1, Patent Document 2, Patent Document 3) And Patent Document 4).
(1) Acid gases such as NOx, SOx, and HF
(2) NH ₃ , Amines and other basic gases
(3) Organic gas (hydrocarbon, etc.)
[0008]
The removal of the organic gas using the chemical filter is based on the physical adsorption of the organic gas to the activated carbon constituting the chemical filter. If the amount of gaseous pollutant adsorbed becomes more than a certain amount, the chemical filter deteriorates in adsorption performance, and therefore needs to be replaced. Usually, the filter is replaced once a year. However, since the chemical filter is expensive, an increase in the frequency of replacement and an increase in the amount of use lead to an increase in manufacturing cost, and a frequent replacement of the filter requires stopping the apparatus, which leads to a decrease in production efficiency.
[0009]
Activated carbon or anion-exchange fiber impregnated with an alkaline substance is generally used as a material for the chemical filter used for removing the acidic gas, and an acidic substance is impregnated on the chemical filter used for removing the basic gas. Activated carbon and cation exchange fibers are used as the raw material, and the acidic gas and the basic gas are chemically removed. Therefore, the adsorption capacity of the acidic gas and the alkaline gas by the chemical filter is larger than that of the organic gas. However, it is difficult to regenerate the activated carbon to which the ion-exchange fibers and chemicals are attached, and it costs more to dispose of the activated carbon.
[0010]
As described above, the chemical filter is effective for adsorbing and removing acidic gas and basic gas, but is expensive and difficult to regenerate. It is conceivable that the device is installed in a semiconductor manufacturing apparatus instead of being installed at a location such as the surface of the semiconductor device to achieve high local cleaning.
[0011]
However, when a chemical filter is installed in a semiconductor manufacturing apparatus, the life of the chemical filter greatly depends on the management situation of an external environment such as a clean room where the semiconductor manufacturing apparatus is installed. That is, when the external environment such as a clean room is sufficiently managed, air with high cleanliness can be purified by a chemical filter installed in the semiconductor manufacturing apparatus, and air with higher cleanliness can be obtained. However, if the external environment such as a clean room is not properly managed, a large amount of gaseous pollutants must be removed when passing low-clean air through the chemical filter, so the burden of removing the chemical filter is large. Become.
[0012]
Therefore, in such a case, unless the chemical filter is replaced frequently, high-purity air cannot be obtained, and quality deterioration of the semiconductor product becomes a problem. Frequent replacement naturally lowers production efficiency. Further, if new equipment or the like is provided in order to extend the life of the filter, the cost is increased accordingly, and it is difficult to manufacture high-quality products while operating the apparatus economically.
[0013]
Incidentally, in order to manufacture semiconductor products of stable quality, it is common to control the temperature and humidity of air supplied to the semiconductor manufacturing apparatus. However, if a chemical filter is installed in a semiconductor manufacturing apparatus, the temperature and humidity of air are likely to deviate from set values due to adsorption of moisture in the air, and there is a concern that the quality of a semiconductor product is adversely affected.
[0014]
As a method for operating the apparatus under stable conditions, a method in which an air conditioner is provided for a semiconductor manufacturing apparatus separately from an air conditioner in a clean room and temperature and humidity are strictly controlled may be considered. However, if air is circulated in the air circulation path connecting the semiconductor manufacturing equipment and the air conditioning equipment to reduce the air conditioning cost, organic gas generated from polymer parts in the semiconductor manufacturing equipment will accumulate over time. In addition, measures for organic gas must be taken.
[0015]
As described above, as semiconductors become more highly integrated, organic gas and ammonia can be used without the need for strict management of clean rooms in which semiconductor manufacturing equipment is installed, frequent filter replacement, and other complicated maintenance and large costs. There is an urgent need to establish a method that can continuously and stably supply air from which gaseous contaminants such as gaseous contaminants have been removed and the temperature and humidity of which have been adjusted to a semiconductor manufacturing apparatus.
[0016]
[Patent Document 1]
Japanese Patent No. 2580893 (Claims, page 1)
[Patent Document 2]
Japanese Patent No. 3035018 (Claims, page 1)
[Patent Document 3]
JP-A-9-168722 (Claims, page 1)
[Patent Document 4]
JP-A-10-340851 (Claims, page 1)
[0017]
[Problems to be solved by the invention]
SUMMARY OF THE INVENTION The present invention has been made in view of such circumstances, and in order to efficiently manufacture a high-performance semiconductor product having a fine integrated circuit pattern line width, frequent replacement of filters and the like and clean room To ensure that gaseous contaminants such as organic gas and ammonia are sufficiently removed and that air with controlled temperature and humidity is continuously and stably supplied to semiconductor manufacturing equipment without strict control of It is an object of the present invention to provide a method which can be performed, and an air purification / air conditioning unit of a semiconductor manufacturing apparatus useful for realizing such a method.
[0018]
[Means for Solving the Problems]
The method of purifying and air-conditioning air supplied to a semiconductor manufacturing apparatus according to the present invention includes providing an adsorbing section in an air circulation path communicating with the semiconductor manufacturing apparatus, and adsorbing and removing gaseous pollutants in air at the adsorbing section. After that, in adjusting the temperature and humidity of the air using the air-conditioning means, the adsorption of the gaseous pollutant by the adsorbent in the adsorption section and the regeneration by heating the adsorbent are alternately repeated, thereby continuously. It is characterized in that gaseous pollutants in the air are adsorbed and removed. Regeneration of the adsorbent is preferable from the economical and environmental aspects, since it is not necessary to newly apply energy by using the excess heat generated by the air conditioning means.
[0019]
It is also desirable to use a material containing a solid acidic substance as the adsorbent of the adsorbing section, particularly, because it can efficiently adsorb and remove ammonia, amines and the like. In order to efficiently adsorb and remove an organic gas in addition to ammonia and amines, a material containing activated carbon in addition to the solid acidic substance is preferably used as the adsorbent.
[0020]
The present invention also specifies an air purification / air conditioning unit of a semiconductor manufacturing apparatus for realizing such a method, and further includes an adsorbing section for removing gaseous pollutants in air with an adsorbent, It is characterized by having an air-conditioning unit for adjusting temperature and humidity and a regenerating unit for heating and regenerating the adsorbent.
[0021]
As the air purification / air conditioning unit of the semiconductor manufacturing apparatus, at least one pair of the adsorbing section and the regenerating section are provided in parallel, and the adsorbent in the adsorbing section adsorbs gaseous pollutants and the regenerative section heats the contaminant. One having switching means for alternately repeating the regeneration of the adsorbent may be mentioned. In addition, as an air purification / air conditioning unit of another semiconductor manufacturing apparatus, the adsorbing section, the regenerating section, and a cooling section for cooling the regenerated adsorbent are formed around a rotation axis, and the adsorbent sequentially passes through the respective sections. One having a rotation means to perform the rotation.
[0022]
As the air purification / air conditioning unit of these semiconductor manufacturing apparatuses, a unit provided with heat exchange means for utilizing the excess heat in the air conditioning unit for regeneration by heating the adsorbent is preferred.
[0023]
BEST MODE FOR CARRYING OUT THE INVENTION
Under the circumstances described above, the present inventors have achieved the best cleaning without frequent maintenance such as frequent replacement of filters and the like and strict management of the clean room in which the semiconductor manufacturing equipment is installed, and enormous costs. In a high-performance semiconductor manufacturing device with a fine line width of integrated circuit patterns that require a high degree of atmosphere, air with controlled temperature and humidity from which gaseous contaminants such as organic gas and ammonia have been removed is continuously applied. The study was conducted from various angles to establish a system that can provide stable supply. as a result,
(1) (a) An adsorbing section is provided in an air circulation path communicating with the semiconductor manufacturing apparatus,
After adsorbing and removing gaseous pollutants in the air,
(B) adjusting the temperature and humidity of the air using an air conditioner; and
(2) It has been found that the gaseous pollutant may be continuously adsorbed and removed by alternately repeating the adsorption of the gaseous pollutant by the adsorbent and the regeneration by heating the adsorbent in the adsorption section. Invented the invention.
[0024]
Hereinafter, the reasons for defining the methods (1) (a), (b) and (2) in the present invention will be described in detail.
[0025]
About (1) (a) above
First, in the method of the present invention, a gaseous pollutant in air is adsorbed and removed by an adsorbent in an adsorbing section provided in an air circulation path communicating with a semiconductor manufacturing apparatus.
[0026]
The present invention does not specify the type of adsorbent used in the adsorption section, but can remove gaseous pollutants such as basic gas such as ammonia and organic gas contained in air in the air circulation path. Any material can be used as long as it can be regenerated by heating, but in order to efficiently remove the gaseous contaminants and recover the adsorption performance, the following materials should be used as the adsorbent.
[0027]
First, the adsorbent is preferably a porous inorganic oxide having a large specific surface area. The shape of the adsorbent can be used in the form of a pellet, a honeycomb, a corrugate, a sheet, a pleat, or the like, but it is preferable that the adsorbent has a large contact area and a low pressure loss. As a method of processing into the above-mentioned shape, a known method such as molding, wash coating, impregnation, spraying, and combing can be employed.
[0028]
Since ammonia as a gaseous contaminant particularly has a large adverse effect on semiconductor production as described above, the adsorbent of the present invention preferably exhibits high adsorption performance to ammonia. Ammonia has a low molecular weight and is therefore hardly physically adsorbed. For example, activated carbon is known to have a very small ammonia adsorption capacity. In general, as a means for adsorbing and removing ammonia, a chemical filter for a basic gas containing activated carbon impregnated with an acid such as sulfuric acid, phosphoric acid, or citric acid is used. Is not preferable from the viewpoints of cost and maintenance because regeneration treatment by heating cannot be performed.
[0029]
In the present invention, it is preferable to use a solid acidic substance acting as an adsorption point for a basic gas such as ammonia as an adsorbent as a means for treating ammonia having a low molecular weight and being hardly physically adsorbed without using the above chemicals or the like. . This is because with the solid acidic substance, ammonia can be sufficiently adsorbed and removed, and the adsorption performance can be recovered by heating.
[0030]
Specific examples of the solid acidic substance include aluminum oxide, zinc oxide, titanium oxide, vanadium oxide, silicon oxide, and silica-alumina. Particularly preferred are a binary composite oxide composed of titanium and silicon, a binary composite oxide composed of titanium and zirconium, and a ternary composite oxide composed of titanium, silicon and zirconium. The individual oxides of titanium, silicon and zirconium each have a weak acidity and a small amount of acid, but the binary oxide or ternary oxide as described above exhibits a remarkable solid acidity and a basic oxide. It acts as an adsorption point for ammonia as a gas.
[0031]
The titanium-based composite oxide as described above can be produced by a conventionally known method. For example, methods for preparing a binary composite oxide composed of titanium and silicon include the following methods (i) to (iii).
[0032]
(I) A method in which titanium tetrachloride is mixed with a silica sol, ammonia is added to form a precipitate, and the precipitate is washed, dried, and fired.
[0033]
(Ii) A method in which an aqueous solution of sodium silicate (water glass) is added to titanium tetrachloride to form a precipitate (coprecipitate), which is washed, dried, and fired.
[0034]
(Iii) A method in which tetraethylsilicate is added to a water-alcohol solution of titanium tetrachloride to form a precipitate by hydrolysis, which is washed, dried, and fired.
[0035]
In each of the above methods, if the coprecipitate is fired at 300 to 650 ° C. for 1 to 10 hours, a binary composite oxide composed of titanium and silicon can be easily obtained. Similarly, binary or ternary composite oxides can be obtained by appropriately adjusting the molar ratio of the titanium source and the silicon source or the zirconium source.
[0036]
Examples of titanium sources that can be used include titanium compounds such as titanium chloride, titanium sulfate, titanium oxalate, and tetraisopropyl titanate. Examples of the silicon source include colloidal silica, water glass, and silicon compounds such as silicon tetrachloride and tetraethyl silicate. Examples of the zirconium source include zirconium chloride, zirconium sulfate and zirconium acetate.
[0037]
Such a titanium-based composite oxide preferably has a titanium content of 20 to 95 mol%, more preferably 50 to 85 mol%. If the content of titanium is less than 20 mol% or more than 95 mol%, solid acidity decreases, which is not preferable.
[0038]
The titanium-based composite oxide thus obtained is 100 m ² / G or more and high heat resistance, so that high ammonia adsorption performance is maintained even when the adsorbent is repeatedly used by heat regeneration.
[0039]
As described above, as a gaseous pollutant, a treatment measure for an organic gas other than ammonia is required more and more in the future. The basic gas such as ammonia or the acidic gas is effectively subjected to chemical adsorption, whereas the organic gas is effectively removed mainly by utilizing physical adsorption.
[0040]
As a method for adsorbing and removing organic gas, physical adsorption on activated carbon, zeolite, silica gel, etc. can be mentioned. Among them, activated carbon in particular has higher adsorption performance for various types of organic gas than zeolite. , And the organic gas adsorbed at a low temperature can be released even in the regeneration treatment. Regarding the type of activated carbon, activated coke, graphite carbon, and activated carbon fiber can be used in addition to commonly used activated carbon.
[0041]
By using activated carbon as an adsorbent in this way, it is possible to remove organic gas generated from a polymer material that is a clean room member, such as a paint, a floor covering, a sheet, a panel, a power cable, a sealing agent, and packing. it can.
[0042]
Specific examples of the organic gas that can be removed include solvents such as toluene, xylene, acetone, trimethylbenzene, ethyl acetate, ethoxyethyl acetate, cyclobenzene, cyclohexane, and methylcyclopentane; dioctyl phthalate, tributyl phosphate, and dioctyl adipate. Plasticizers such as butylhydroxytoluene as an antioxidant; and cyclic siloxane as a sealing agent. In addition, butyl acetate, methoxypropanol, ethyl lactate, hexamethyldisilazane, methoxypropyl acetate, ethoxyethyl acetate, trimethylammonium hydride, and monoethanol used as process solvents for resist solvents, surface modifiers, developers, and strippers Amines, N-methylpyrrolidone and the like.
[0043]
Preferred examples of the adsorbent include those in which a solid acidic substance is used in a range of 20 to 80% by mass and activated carbon in a range of 80 to 20% by mass, and such an adsorbent composition is formed into a honeycomb shape or the like. It should be processed.
[0044]
When the adsorbent composition is formed into a honeycomb shape, for example, the adsorbent has a two-layer structure, an adsorption layer mainly composed of a solid acidic substance is provided in a front layer, and an adsorption layer mainly composed of activated carbon is formed in a rear layer. If provided, it is possible to mainly remove ammonia in the front layer and then mainly remove organic gas in the rear layer. Alternatively, a two-layer structure in the reverse order to the above may be adopted, in which the organic gas is removed in the front layer and the ammonia is removed in the rear layer.
[0045]
In addition to the solid acidic substance and activated carbon, various inorganic oxides such as zeolite, activated clay, magnesium silicate, sepiolite, and clay mineral may be appropriately added as an adsorbent or the like.
[0046]
In the case where the adsorbing section is used by circulating air forming an atmosphere of the semiconductor manufacturing apparatus, in addition to being installed in an air circulation path capable of purifying air including gaseous pollutants discharged from the semiconductor manufacturing apparatus, It may be installed at an air intake when air is taken in from outside the air circulation path. With this arrangement, gaseous pollutants can be efficiently removed, and highly clean air can be supplied to the semiconductor manufacturing apparatus. In addition, depending on the semiconductor manufacturing equipment, gaseous pollutants may be generated during the semiconductor manufacturing process. In such a case, the above-described adsorption unit is installed at the air outlet of the semiconductor manufacturing equipment, so that the gaseous pollutants may be generated. Can be prevented from diffusing into the air circulation path.
[0047]
To remove particulate contaminants along with gaseous contaminants such as ammonia, amines, and organic gases, for example, install a dust filter such as a medium-performance dust filter, HEPA filter, ULPA filter, or electrostatic filter. This is of course also effective. The dust removal filter can be installed at an intermediate position between the adsorption unit loaded with the adsorbent and the air conditioning unit that controls the temperature and humidity of air, or can be installed at the air outlet of the air conditioning unit.
[0048]
About (1) (b) above
After the gaseous pollutants in the air are adsorbed and removed by the adsorbing section, the temperature and humidity of the air are adjusted using an air conditioner. For example, if the adsorbent absorbs moisture together with gaseous pollutants in the air and the humidity of the air changes before and after contact with the adsorbent, supplying air directly to the semiconductor manufacturing equipment may adversely affect semiconductor manufacturing. Can be considered. However, even in such a case, by providing the air-conditioning means as described above, it is possible to control the air passing through the suction section to a predetermined temperature and humidity.
[0049]
For example, in a photoresist coating step, an exposure step, and a development step in a semiconductor manufacturing process, strict adjustment is performed so that the temperature is (23 ± 0.1) ° C. and the humidity is (45 ± 3)% RH in an air conditioning unit. Is mentioned.
[0050]
About ② above
In the present invention, the air is continuously purified by alternately repeating the adsorption of the gaseous pollutant by the adsorbent in the adsorption section and the regeneration of the adsorbent by heating in the regeneration section. The regeneration of the adsorbent is based on the fact that the adsorbed gaseous contaminants are released by heating the adsorbent.
[0051]
Means for heating the adsorbent is not particularly limited, and an electric heater or the like can be used. However, it is preferable from an economical point of view and an environmental point to utilize waste heat obtained from a high-temperature refrigerant generated in an air conditioner used.
[0052]
Specifically, air is taken in from the outside of the air circulation path as air for regeneration of the adsorbent by a fan, and the air for regeneration of the adsorbent is cooled to a predetermined temperature by, for example, using a heat exchanger with the waste heat of a compression type high-temperature refrigerant. By heating and bringing the heated air into contact with the adsorbent, gaseous pollutants can be released from the adsorbent, and the adsorption performance can be restored. For the heating, waste heat of the high-temperature refrigerant and an auxiliary electric heater may be used in combination.
[0053]
In order to desorb the gaseous pollutant adsorbed on the adsorbent, it is necessary to heat the adsorbent at a temperature of 60 to 100 ° C, more preferably 70 to 90 ° C, depending on the kind of the gaseous pollutant adsorbed. Good. If the heating temperature is lower than 60 ° C., the adsorbed gaseous pollutants will not be sufficiently released, and the recovery of the adsorption performance will be insufficient. In addition, when the adsorbent is heated only with the waste heat, if the heating temperature exceeds 100 ° C., the waste heat of the high-temperature refrigerant alone is not sufficient to heat, and eventually energy needs to be added and the cost is increased, which is not preferable.
[0054]
As described above, the gaseous contaminants adsorbed on the adsorbent are gradually released by the heat treatment. When the concentration of the gaseous pollutant is extremely low, on the order of ppb, and the concentration ratio is low, the concentration of the gaseous pollutant is substantially the same as that of the outside air. The air containing the contaminants may be discharged outside as it is.
[0055]
Here, the concentration ratio is
(Amount of air introduced into the air circulation path) / (Amount of air exhausted out of the air circulation path during regeneration of the adsorbent)
When the concentration ratio is low, the case where the amount of air exhausted outside the room after the regeneration of the adsorbent is larger than the amount of air introduced into the air circulation path.
[0056]
If the concentration ratio is extremely low, the amount of air discharged outside the air circulation path becomes large.For example, when a semiconductor manufacturing apparatus is installed in a clean room, the temperature and humidity of the clean room are liable to change. This leads to higher costs. Accordingly, in order to suppress an increase in the cost of air conditioning in a clean room, the concentration ratio is preferably 10 times or more, and more preferably 30 times or more.
[0057]
In addition, when the concentration ratio is high (that is, when the amount of air exhausted to the outside of the air circulation path during regeneration of the adsorbent is smaller than the amount of air introduced into the air circulation path), the gas in the discharged air When the concentration of the gaseous pollutant is high, the air containing the gaseous pollutant can be heated to 100 to 350 ° C. using a platinum-based catalyst or the like to oxidize and decompose the gaseous pollutant to make it harmless. .
[0058]
For example, when using a rotary rotor type air purification / air conditioning unit to be described later, when the adsorption of gaseous pollutants in the adsorption section and the regeneration of the adsorbent in the regeneration section are repeatedly and continuously performed, the enrichment ratio is adjusted. It can be set to about 10 to 100 times.
[0059]
However, in the case of the rotary rotor type, if the operation is performed at a high concentration ratio exceeding about 100 times, the regeneration of the adsorbent becomes insufficient. Is preferred.
[0060]
In a multi-tower switching air purifying / air-conditioning unit, the enrichment ratio can be easily increased by extending the period in which a later-described tower is used as an adsorber, and the enrichment ratio is set within a range of about 30 to 300 times. can do. For example, if the switching frequency of the adsorption section / regeneration section of the tower is set to about once a month, the concentration ratio can be controlled within the above range. At this time, it is necessary to fill the column with an amount of adsorbent capable of maintaining the adsorption performance for one month or more. After filling, the column can be operated semi-permanently by switching operation of the adsorption unit / regeneration unit. It is believed that the cost and effort can be significantly reduced as compared to the need to replace the chemical filter about once a year.
[0061]
The present invention also specifies an air purification / air conditioning unit of a semiconductor manufacturing apparatus for realizing such a method.
[0062]
The air purification / air conditioning unit of the semiconductor manufacturing apparatus of the present invention includes:
(A) an adsorbing section for removing gaseous pollutants in the air with an adsorbent;
(B) an air conditioner for adjusting the temperature and humidity of the air;
(C) a regenerating unit that heats the adsorbent and separates and regenerates gaseous pollutants adsorbed on the adsorbent;
Is characterized by having the following.
[0063]
In the air purification / air conditioning unit of the semiconductor manufacturing apparatus according to the present invention, the air containing the gaseous pollutant passes through the air conditioning section from the (A) adsorption section to remove the gaseous pollutant, and A system in which temperature and humidity are adjusted and supplied to a semiconductor manufacturing apparatus, and, in addition, a (C) regenerating unit for regenerating the adsorption performance of the adsorbent having reduced adsorption performance is an essential component. It is.
[0064]
As described above, by additionally providing the regenerating section for regenerating the adsorbent filled in the adsorbing section, it is possible to configure an air purification / air conditioning unit of a semiconductor manufacturing apparatus which is compact and very easy to maintain. it can.
[0065]
From the viewpoint of economy and environment, it is preferable that the regeneration of the adsorbent in the regeneration unit is performed by using the excess heat of the high-temperature refrigerant in the air conditioning unit. A heat exchanger or the like can be installed. When it is difficult to sufficiently remove the gaseous pollutant from the adsorbent only by the excess heat, an electric heater or the like may be additionally provided as auxiliary heating equipment.
[0066]
The air purifying unit of the present invention does not exclude components other than the above (A) to (C). For example, a blower fan, a dust filter, a chemical filter, or the like may be provided.
[0067]
As an embodiment of such an air purification / air conditioning unit of the semiconductor manufacturing apparatus of the present invention, for example, a multi-tower switching type or a rotary rotor type in which an adsorbent is regenerated at any time is cited.
[0068]
In the multi-tower switching type, at least one pair of the adsorbing section (tower) and the regenerating section (tower) filled with adsorbent are provided. Adsorption of gaseous pollutants by the adsorbing material in the adsorbing section and adsorption by heating in the regenerating section. It has switching means to alternately repeat the regeneration of the material, and periodically switches the line by an automatic valve in conjunction with a timer, and alternately repeats the adsorption and the regeneration, so that the apparatus can be used at the time of regeneration of the adsorbent. The gaseous pollutants can be continuously adsorbed and removed without stopping, and the purified air can be supplied to the semiconductor manufacturing apparatus.
[0069]
That is, for example, when the adsorption capacity of a tower (hereinafter, referred to as “tower A”) serving as an adsorption unit for gaseous pollutants is reduced, another tower (hereinafter, referred to as “tower B”) is switched to operate as an adsorption unit. By continuously adsorbing and removing gaseous pollutants at the same time, on the other hand, heating and regenerating the tower A with reduced adsorption performance, so that when the adsorption performance of the tower B decreases, the tower A again works as an adsorption section. In addition, the cleaning air can be continuously supplied to the semiconductor manufacturing apparatus.
[0070]
As another method for continuously performing the adsorption and the heat regeneration, it is also useful to make the unit of the present invention a rotary rotor type. In this rotary rotor type, the adsorbent sequentially passes through three zones of an adsorbing section, a regenerating section, and a cooling section, which are divided around a rotation axis, so that the adsorbent adsorbs gaseous pollutants and removes the adsorbent. Regeneration and cooling of the adsorbent, which has become high during regeneration, can be continuously and repeatedly performed.
[0071]
As a semiconductor manufacturing apparatus to which the present invention can be applied, for example, a resist coating apparatus (coater) for forming a resist film on the surface of a semiconductor wafer, or a predetermined circuit pattern on a resist film applied on the surface of a semiconductor wafer by light irradiation An exposure device (stepper) for transferring, a developing device (developer) for applying a developing solution to the surface of the semiconductor wafer after exposure and performing a developing process, and the like are exemplified.
[0072]
In addition, the present invention can be suitably used for a carrier box, a clean box, a stocker, a transfer space, an interface, and the like as facilities related to semiconductor manufacturing. Further, the present invention can be applied to a clean room or a local space (mini-environment / micro-environment) in the clean room.
[0073]
【Example】
Hereinafter, the present invention will be described in more detail with reference to FIGS. 1 to 3 below as embodiments of the present invention. However, the present invention is not limited to the following examples and conforms to the above and following points. It is also possible to carry out the present invention with appropriate modifications within a possible range, and all of them are included in the technical scope of the present invention.
[0074]
In particular, in the following embodiments, a case where an exposure process is performed in a semiconductor manufacturing apparatus will be described. However, it is needless to say that the present invention can be applied to a case where a resist coating process, a developing process, and the like are performed in a semiconductor manufacturing device.
[0075]
<Example 1>
FIG. 1 schematically illustrates an apparatus for realizing the method of the present invention. The semiconductor manufacturing apparatus 1 is installed in a clean room, and forms a semi-enclosed space like the clean room.
[0076]
As shown in FIG. 1, the stage 10 on which the wafer 3 is mounted is carried into the exposure processing chamber 2 of the semiconductor manufacturing apparatus 1 by the transfer unit 11, and after the exposure processing, is again carried out of the apparatus by the transfer unit 11, and at the same time, Is carried into the exposure processing chamber 2 by another transfer section (not shown).
[0077]
On the other hand, the air purification / air conditioning unit 4 removes gaseous contaminants such as ammonia contained in the air discharged from the exposure processing chamber 2 and the air introduced from outside the air circulation path, and reduces the temperature and humidity of the air. It is a mechanism to adjust. Specifically, the air purification / air conditioning unit 4 includes an adsorbing section 5, an air conditioning section 7, an adsorbent regeneration air heating section 13, and the like. Material is filled.
[0078]
The air introduced into the air purification / air conditioning unit 4 from the air intake 14 by the blower fan 8 is first adsorbed and removed by the adsorbing section 5 of the gaseous pollutant. The air from which the gaseous pollutants have been removed in this way is then introduced into the air conditioning unit 7, where the temperature and humidity are monitored by sensors, and the air is heated or reduced to a predetermined temperature. Humidification or dehumidification is a mechanism.
[0079]
The air from which the gaseous contaminants have been removed and whose temperature and humidity have been adjusted passes through the medium-performance dust filter 9 to remove the particulate contaminants, and is then introduced into the exposure processing chamber 2. After the exposure processing, the air in the exposure processing chamber 2 is discharged into the air circulation path by the circulation fan 12 and reused.
[0080]
The adsorbent to which the gaseous pollutant has been adsorbed is regenerated by heating the adsorbent and releasing the gaseous pollutant from the adsorbent. Excess heat can be used for the regeneration of the adsorbent as follows. That is, the high-temperature refrigerant discharged from the refrigerating compressor incorporated in the air conditioner 7 flows through the heating heat transfer tube 15 disposed in the adsorbent regeneration air heater 13, and the adsorbent regeneration air In the heating unit 13, the adsorbent regeneration air taken in from outside the air purification / air conditioning unit 4 is heated by the excess heat of the high-temperature refrigerant, and the high-temperature air heats the adsorbent, thereby removing gaseous pollutants from the adsorbent. Break away from
[0081]
<Example 2>
FIG. 2 schematically illustrates a case in which the air purification / air conditioning unit 4 of the first embodiment is a multi-tower switching type. Instead of the adsorption unit 5 in FIG. 1 and the like, FIG. Are arranged in parallel. Each tower is filled with an adsorbent 6, and air is introduced into one of the towers to adsorb and remove gaseous pollutants such as ammonia and organic gas. On the other hand, the other column with reduced removal performance functions as a regeneration unit, and the adsorbent is regenerated by heating. That is, if one tower constantly acts as an adsorbing section and the other tower acts as a regenerating section and the adsorbing performance of one tower decreases, the air flow path uses an automatic valve such as a solenoid valve. The air is passed through the tower whose adsorption performance has been restored, and the air is continuously purified.
[0082]
FIG. 2 shows an example in which the open state of the automatic valve 18 is indicated by a circle and the closed state is indicated by a circle. Air flows into the tower 5B, and the adsorption and removal of gaseous pollutants is performed in the tower 5B. This shows a state in which the adsorbent is being regenerated in the tower 5A in which the adsorption performance has been reduced.
[0083]
The regeneration treatment of the adsorbent in the tower 5A is performed as follows. That is, the air taken in from the adsorbent regeneration fan 16 is heated to a predetermined temperature by the adsorbent regeneration air heating unit 13, and an automatic valve installed between the adsorbent regeneration air heating unit 13 and the adsorption unit. 19, the adsorbent 6 in the tower 5A is heated and regenerated by the high-temperature air. The heating of the regeneration air is performed by heating the excess heat obtained by passing the high-temperature refrigerant discharged from the refrigerating compressor incorporated in the air conditioning unit to the heating heat transfer tube 15 of the adsorbent regeneration air heating unit 13. Use as a source. Air containing gaseous pollutants generated by regeneration of the adsorbent is oxidized and detoxified and detoxified using a catalyst (not shown) in accordance with the concentration of the gaseous pollutants contained, and air is purified and air-conditioned from the purge line 17. It is discharged out of the unit 4.
[0084]
<Example 3>
FIG. 3 is a schematic diagram showing another method of continuously performing adsorption of a gaseous pollutant and regeneration of an adsorbent, in which the air purification / air conditioning unit 4 of the first embodiment (FIG. 1) is a rotary rotor type. This is a typical example. The disk-shaped rotary rotor 21 filled with the adsorbent 6 is configured to sequentially pass through three zones of an adsorbing section 20, a regenerating section 24, and a cooling section (a cooling section is not shown) by rotation. The rotor 21 is configured to rotate by driving a rotor rotation shaft 22 by driving a rotation motor 23. With such a structure, the adsorbent 6 filled in the rotary rotor 21 sequentially passes through each zone, and continuously absorbs gaseous pollutants, regenerates the adsorbent, and cools the high-temperature adsorbent immediately after the regeneration. Can be repeated. The air introduced into the adsorption unit 20 comes into contact with the adsorbent 6 to remove gaseous contaminants, and the temperature and humidity are adjusted by the air conditioning unit 7 and sent to the exposure processing chamber.
[0085]
On the other hand, the regeneration of the adsorbent 6 in the rotary rotor 21 in which the adsorption performance of the gaseous pollutants has been reduced is performed as follows. That is, the adsorbent regeneration air taken in from the outside of the air purification / air conditioning unit by the adsorbent regeneration air fan 16 is heated to a predetermined temperature by the adsorbent regeneration air heater 13, and the heated air is adsorbed. The adsorbent 6 is sent to the material regenerating section 24, where the adsorbent 6 is heated and regenerated.
[0086]
In the heating of the adsorbent regeneration air, similarly to the second embodiment, the air is discharged from a refrigeration compressor (not shown) built in the air conditioner obtained through the heating heat transfer tube 15 of the adsorbent regeneration air heater 13. Utilizes surplus heat from high-temperature refrigerant. Air containing gaseous pollutants generated by regeneration of the adsorbent is discharged from the purge line 17 to the outside of the room. When the concentration of the gaseous pollutant in the discharged air is high, the gaseous pollutant may be oxidized, decomposed and made harmless by heating using a platinum-based catalyst (not shown) or the like. The heat-regenerated adsorbent is cooled by a cooling unit (not shown) and then transferred to the adsorption unit 20.
[0087]
【The invention's effect】
The present invention is configured as described above, and according to the air purification / air conditioning method of the present invention, a high performance semiconductor that requires an atmosphere with the highest cleanliness and has a fine integrated circuit pattern line width. Gaseous contaminants such as organic gas and ammonia without the need for complicated maintenance and enormous costs, such as frequent replacement of filters and strict management of the clean room where semiconductor manufacturing equipment is installed. Is removed and air with controlled temperature and humidity can be continuously and stably supplied. In particular, in the present invention, since the adsorbent can be used repeatedly by effectively utilizing the adsorption / desorption action of the adsorbent, maintenance can be facilitated and the maintenance cost can be reduced.
[Brief description of the drawings]
FIG. 1 is a schematic illustration illustrating an apparatus configured to carry out the method of the present invention.
FIG. 2 is a schematic explanatory view illustrating an air purification / air conditioning unit of a semiconductor manufacturing apparatus configured to carry out the method of the present invention.
FIG. 3 is a schematic explanatory view illustrating another air purification / air conditioning unit of a semiconductor manufacturing apparatus configured to carry out the method of the present invention.
[Explanation of symbols]
1 Semiconductor manufacturing equipment
2 Wafer processing chamber (exposure processing chamber)
3 wafer
4 Air purification / air conditioning unit
5 Suction unit
5A, 5B adsorbent packed tower
6 Adsorbent
7 Air conditioning unit
8 blower fan
9 Medium performance dust filter
10 stages
11 Transport unit
12 Circulation fan
13 Air heating unit for adsorbent regeneration
14 Air intake
15 Heat transfer tube
16 Adsorbent regeneration air fan
17 Purge line
18 Automatic valve (for gas control)
19. Automatic valve (for adsorbent regeneration)
20 Suction section
21 Rotating rotor
22 Rotor shaft
23 Rotation motor
24 (heating) regeneration unit

Claims (8)

Providing an adsorption unit in the air circulation path communicating with the semiconductor manufacturing equipment, and after adsorbing and removing gaseous pollutants in the air at the adsorption unit, in adjusting the temperature and humidity of the air using air conditioning means,
A semiconductor manufacturing apparatus for continuously adsorbing and removing gaseous pollutants in air by alternately repeating adsorption of gaseous pollutants by an adsorbent in an adsorption section and regeneration by heating of the adsorbent. Purification and air conditioning method for supplying air to the air. The method for purifying and air-conditioning air supplied to a semiconductor manufacturing apparatus according to claim 1, wherein the regeneration by heating the adsorbent is performed using excess heat generated by the air-conditioning unit. 3. The method for purifying and air-conditioning air supplied to a semiconductor manufacturing apparatus according to claim 1, wherein a material containing a solid acidic substance is used as the adsorbent. 3. The method for purifying and air-conditioning air supplied to a semiconductor manufacturing apparatus according to claim 1, wherein a material containing a solid acidic substance and activated carbon is used as the adsorbent. A semiconductor comprising: an adsorbing section for removing gaseous pollutants in air with an adsorbent; an air conditioning section for adjusting the temperature and humidity of air; and a regenerating section for heating and regenerating the adsorbent. Air purification and air conditioning unit for manufacturing equipment. At least one pair of the adsorbing section and the regenerating section is provided, and a switching means for alternately repeating the adsorption of the gaseous pollutant by the adsorbent in the adsorbing section and the regeneration of the adsorbent by heating in the regenerating section is provided. An air purification / air conditioning unit for a semiconductor manufacturing apparatus according to claim 5. 6. The cooling unit according to claim 5, wherein a cooling unit for cooling the adsorbing unit, the regenerating unit, and the regenerated adsorbent is formed around a rotation axis, and a rotating unit is provided to allow the adsorbent to sequentially pass through the respective units. Air purification and air conditioning unit for semiconductor manufacturing equipment. The air purification / air conditioning unit of a semiconductor manufacturing apparatus according to any one of claims 5 to 7, further comprising heat exchange means for utilizing surplus heat in the air conditioning unit for regeneration by heating the adsorbent.

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