JPS634616A - Steam treating unit - Google Patents

Abstract

PURPOSE:To reliaze highly reliable steam drying, by providing a steam feed channel which as a filter inserted therein and communicates between a steam generating section and a drying section, and providing the filter with a heating means. CONSTITUTION:A filter mechanism 13 inserted in a steam feed tube 11 is provided with a heater 15 so that a filter body 14 is heated constantly at a predetermined temperature. Treating steam 7 passing through the filter mechanism 13 is thereby prevented from being liquefied and a large amount of treating steam 7 can be supplied quickly into a treating tank 4. Further, the efficiency of the steam drying operation can be improved. Still further, by providing the filter mechanism 13 midway on the steam feed tube 11, foreign substances are prevented from entering into the treating chamber 4 together with the treating steam 7 and the steam drying can be performed in a reliable manner.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a technology that is particularly effective when applied to processing technology, for example, a technology that is particularly effective when applied to steam processing of semiconductor wafers in the manufacture of semiconductor devices. It's about technology.

[Conventional technology]

Steam drying treatment for semiconductor wafers is described, for example, in Japanese Patent Laid-Open No. 16807/1983, and the outline is that a semiconductor wafer is immersed in a vapor atmosphere of an organic solvent, and water droplets attached to the surface of the semiconductor wafer are dried. The aim is to dry the surface of the semiconductor wafer by removing such substances.

The present inventor studied the steam treatment technology as described above. Although the following is not a publicly known technique, it is a technique studied by the present inventor, and its outline is as follows.

In other words, in the steam drying apparatus having the above-mentioned structure, a solution such as an organic solvent is stored at the bottom and steam treatment is performed above the solution, which is a so-called integrated structure of a steam generation section and a processing section. It is being However, in processing equipment with such a body structure, the amount of steam in the processing tank decreases rapidly when the material to be processed is introduced, and it takes a long time to recover one volume to the specified value. becomes.

Therefore, the device structure is such that the steam generation section and the processing section are separated, the steam generated by the steam generation section is transferred to the processing section via a conveyance path, and a large amount of processed steam is supplied to the processing section in a short time. Conceivable.

By the way, in the device structure in which the processing section and the steam generation section are separated in this way, in order to control the supply of processing steam to the processing section, a control pulp that controls the supply amount of processing steam is installed in the middle of the transfer path. However, there is a risk that dust may be generated due to the opening and closing operations of the control pulp, and the dust-generating substances may be transferred to the processing section while being mixed in the processing steam. From this point of view, it is conceivable to insert a filter in the middle of the transfer path to remove foreign substances from the treated steam.

[Problem that the invention seeks to solve]

However, when a filter is inserted in the middle of the transfer path in this way, the transferred processed vapor often liquefies at the filter and cannot reach the processing section in vapor form. This was revealed by the inventor.

The present invention has been made focusing on the above problems,
The purpose is to provide a technique that can improve the reliability of steam processing.

The above and other objects and novel features of the present invention will become apparent from the description of this specification and the accompanying drawings.

[Means for solving problems]

A brief summary of typical inventions disclosed in this application is as follows.

That is, a filter is interposed in the steam transfer path that communicates the steam generation section and the processing section, and at least the filter is provided with heating means.

[Effect]

According to the above-mentioned means, the inside of the filter can be maintained at a predetermined heating state, so it is possible to prevent the processing steam from being liquefied when passing through the filter, and to provide a clean and sufficient amount of steam to the processing section. can be supplied.

[Example 1] FIG. 1 is a schematic explanatory diagram showing a steam treatment apparatus that is an example of the present invention.

The steam processing apparatus 1 of the first embodiment is, for example, a steam drying apparatus for drying the surface of a semiconductor wafer 2 (workpiece),
A steam generation tank 3 which is a steam generation section and a processing tank 4 which is a processing section
It has

A processing liquid 5 such as a la solvent such as isopropyl alcohol (IPA) is stored inside the steam generation tank 3, and is heated by a heater 6 provided at the bottom of the steam generation tank 3 to generate processing steam 7. The structure is generated.

On the other hand, the processing tank 4 is configured such that the semiconductor wafer 2 as the object to be processed is placed inside the processing tank 4, and the interior of the processing tank 4 is constantly kept by a heater 8 provided near the outer surface of the processing tank 4. The temperature is controlled to be a predetermined temperature, for example, 82° C. or higher at which the existing solvent can maintain its vapor state.

The semiconductor wafer 2 is transported in and out of the processing tank 4 while being housed in a jig or the like (not shown). Furthermore, a waste liquid pipe 9 is connected to the inner bottom of the processing tank 4.
The structure is such that the processing waste liquid 10 dropped from the semiconductor wafer 2 to the bottom of the processing tank 4 is discharged to the outside.

The steam generation tank 3 and the processing tank 4 are connected by a steam transfer pipe 11 as a steam transfer path, and the processing steam 7 from the steam generation tank 3 is supplied to the processing tank 4 through the steam transfer pipe 11. It becomes. A control pulp 12 is interposed in a midway portion of the steam transfer pipe 11 near the steam generation tank 3, so that the supply of the treated steam 7 is controlled.

A filter mechanism 13 is attached to a portion of the steam transfer pipe 11 near the processing tank 4. This filter mechanism 13 includes a filter body 14 made of a porous material provided in the central portion so as to block the steam transfer pipe 11, and a heater provided around the filter body 14 so as to sandwich the filter body 14. 15 is isolated from the outside by a heat insulating material 16, and due to the action of the heater 15, the inside of the filter body 14 is kept at a low temperature (at which the treated steam 7 can maintain its vapor state, for example, about 82°C). It is controlled to become.

Next, the operation of this embodiment will be explained.

First, a processing liquid 5 such as an organic solvent stored inside the steam generation tank 3 is heated by a heater 6 to reach a boiling point of, for example, 8.
When the temperature reaches about 2° C., the inside of the steam generation tank 3 is filled with an atmosphere of the treated steam 7.

Next, when the semiconductor wafer 2 housed in a jig (not shown) is transferred into the processing tank 4, the 'iritm valve 12 is opened, and processing steam 7 is supplied to the steam transfer pipe 11'. Here, due to dust generation due to the operation of the control valve 12 , minute foreign matter may be mixed into the treated steam 7 , but such minute foreign matter is removed when the treated steam 7 passes through the filter mechanism 13 . It is removed from the steam 7.

Here, it is possible that the processing steam 7 condenses and liquefies when passing through the filter mechanism 13, but according to the first embodiment, the inside of the filter body 14 is processed by the function of the heater 15. Since the temperature is maintained at a temperature higher than the boiling point of the organic solvent that is the liquid 5, the treated vapor 7 containing the w1 solvent does not liquefy when passing through the filter body 14, but instead becomes the purified vapor. They are sequentially supplied into the processing tank 4 in this state.

In the processing tank 4, when the processing vapor 7 of the organic solvent comes into contact with the semiconductor wafer 2 at room temperature, it condenses on the surface of the semiconductor wafer 2 and liquefies. Here, water droplets and the like adhering to the surface of the semiconductor wafer 2 are dissolved and decomposed into droplets of the aforesaid solvent, fall to the bottom of the processing tank 4, and are removed, and are discharged to the outside via the waste liquid pipe 9. . This phenomenon is repeated until the temperature of the semiconductor wafer 2 and the surrounding atmosphere of the processing steam 7 reach approximately the same temperature, thereby bringing the surface of the semiconductor wafer 2 into a predetermined dry state.

As described above, according to this embodiment, the following effects can be obtained.

+11. @Filter mechanism 1 installed in pneumatic transfer pipe 11
3 is equipped with a heater 15 to keep the filter body 14 in a predetermined heated state at all times, so that the filter mechanism 13
It is possible to prevent the processing steam 7 from liquefying when passing through the processing tank 4.
A large amount of processing steam 7 can be rapidly supplied within the chamber.

(2) The above +11 can improve the efficiency of the steam drying process.

(3) By providing the filter mechanism 13 in the steam transfer pipe 11, it is possible to prevent foreign matter from being mixed into the processing tank 4 together with the processing steam 7, and a highly reliable steam drying process can be realized.

[Embodiment 2] FIG. 2 is a schematic perspective view showing a filter mechanism applied to a steam drying apparatus according to another embodiment of the present invention.

The filter mechanism 21 of the second embodiment includes a pair of plate heaters 23a provided perpendicularly to the steam transfer pipe 11;
23b, and this plate-shaped heater 23a.

It consists of a thin plate-like filter 24 held between two parts 23b. A plurality of holes 25 are formed in each of the plate heaters 23a, and each hole 25 is blocked by a filter 24 in the middle thereof.

Therefore, in the second embodiment, the processing steam 7 sent through the one-gas transfer pipe 11 is transferred to the plate heaters 23a, 23.
When passing through the hole 25 of b, foreign matter is removed by the action of the filter 24.

In this manner, according to the second embodiment, liquefaction of the treated vapor 7 can be prevented with a simple filter structure. Also filter 24
can be easily replaced.

[Embodiment 3] FIG. 3 is a schematic sectional view showing a filter mechanism applied to a steam drying apparatus according to another embodiment of the present invention.

In this third embodiment, the filter mechanism 31 is the vapor transfer pipe 11.
It consists of a filter body 14 made of a porous material filled in a predetermined interior of the filter body 14, and a heating pipe 32 that is piped through the filter body 14.

The heating tube 32 has a structure in which a heating fluid 33 such as heated steam or high-temperature water is circulated, so that the filter body 14 can maintain a temperature equal to or higher than the boiling point of the organic solvent.

In this way, in the third embodiment, the heating fluid 33 is circulated within the heating tube 32 without using an electric heater, so there is no risk of ignition of the aqueous solvent, and the system is highly safe. Heating of the processing steam 7 can be achieved. Moreover, as a result, it becomes possible to directly install the heating pipe 32 inside the filter body 14, and liquefaction of the treated steam 7 within the filter body 14 can be more completely prevented.

Although the invention made by the present inventor has been specifically explained above based on Examples, it goes without saying that the present invention is not limited to the Examples and can be modified in various ways without departing from the gist thereof. For example, as for the heating means, only those using an electric heater or a heating tube have been described, but the invention is not limited to this, and other heating means such as a lamp heater may also be used. The heating tube may have a structure such that it is wound around the outer periphery of a vapor transfer tube in which a filter is installed.

In the above explanation, the invention made by the present inventor was mainly applied to a so-called steam drying apparatus, which is the field of use thereof, but the invention is not limited to this, and can also be applied to, for example, a steam etching apparatus. .

〔Effect of the invention〕

A brief explanation of the effects obtained by typical inventions disclosed in this application is as follows.

In other words, it is a processing apparatus that performs a predetermined process on the workpiece by placing the workpiece in processing steam, and includes a steam generation section that generates the processing steam, and a processing section in which the workpiece is placed. and a steam transfer path connecting the steam generation section and the processing section and having a filter interposed therein,
By having a steam treatment device structure in which at least the filter is equipped with a heating means, it is possible to remove foreign substances when the treated steam passes through the filter, and prevent the liquefaction of the treated steam, thereby improving reliability in the treatment section. It is possible to achieve high steam processing.

[Brief explanation of drawings]

FIG. 1 is a schematic explanatory diagram showing a steam treatment apparatus which is an embodiment of the present invention, FIG. 2 is a schematic perspective view showing a filter structure of a steam treatment apparatus which is another embodiment 2 of the present invention, and FIG. FIG. 2 is a schematic cross-sectional view showing a filter structure of a steam treatment apparatus according to a third embodiment of the present invention. 1... Steam processing equipment, 2... Semiconductor wafer, 3...
・Steam generation tank, 4... Processing tank, 5... Processing liquid, 6.
... Heater, 7... Processing steam, 8... Heater, 9.
... Waste liquid pipe, 10... Processed waste liquid, 11... Steam transfer pipe, 12... f, If control valve, 13... Filter mechanism, 14... Filter body, 15... Heater, 16... Insulating material, 21... Filter mechanism, 23
a, 23b... plate heater, 24... filter,
25... Hole, 31... Filter mechanism, 32...
Heating tube, 33... heating fluid. Agent: Patent attorney Katsuo Ogawa:,! ζ”WC

Claims (1)

[Scope of Claims] 1. A processing apparatus that performs a predetermined treatment on the object by placing the object in the processing steam, the device comprising: a steam generating section that generates the processing steam; and a steam transfer path in which a filter is interposed and communicates the steam generation section with the treatment section, and at least the filter is provided with a heating means. Steam treatment equipment. 2. The steam processing apparatus according to claim 1, wherein the heating means is an electric heater. 3. The steam processing apparatus according to claim 1, wherein the heating means is a heating tube that circulates high-temperature fluid therein. 4. Claim 1, characterized in that the object to be processed is a semiconductor wafer and the processing vapor is an organic solvent vapor;
The steam treatment apparatus according to item 2 or 3.