JPH06275596A - Vapor treatment device - Google Patents

Abstract

PURPOSE:To inhibit oxidation of the surface of a semiconductor wafer due to vapor drying. CONSTITUTION:An infection nozzle 4 for injecting a vaporized IPA injection liquid 13 to a wafer 12 carried into a vapor tank is provided in the title device with a vapor tank 3 which has a zigzag pipe 2 for cooling at an upper part and houses a treatment liquid (IPA liquid) 10 at a lower part, a heater 1 for vaporizing the IPA liquid 10 in the vapor tank, and a loader 5 for carrying in/out a cassette 20 where the wafer 12 is housed in a vapor layer 17 at the upper part of the vapor tank. When the cassette 20 is loaded into the vapor tank 3, temperature decreases and the vapor layer 17 descends. However, the wafer 12 is covered with the IPA injection liquid 13, thus inhibiting the oxidation of the wafer 12 at a high temperature without being exposed to air.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vapor processing apparatus, for example, a vapor drying apparatus for drying an object to be processed with steam (vapor), which is effective when applied to the drying of a semiconductor thin plate (wafer) in the production of semiconductor devices. Regarding technology.

[0002]

2. Description of the Related Art In the manufacture of semiconductor devices, a wafer is repeatedly subjected to photolithography. Then, the cleaning / drying process of the wafer is performed each time. One of the wafer drying processes is vapor drying. The vapor drying is described in, for example, “solid state tecnology (Japanese version) Japanese edition”, published by Nippon SST Co., Ltd., April 1991, April 15, the same day, P21. In this document, regarding vapor drying, "Wafer drying is performed by single-wafer, in-line, vapor drying. IPA (or other solvent) is self-taining to obtain a process temperature by an external heating mechanism. The wafer should be positioned with the J-arm and vaporized to dry. "

[Electronic Materials] 199 issued by the Industrial Research Board
July 2nd issue, issued July 1st of the same year, P38-P42,
A liquid crystal panel cleaning device is described. This document discloses a freon vapor dryer. Also,
It is also described that IPA vapor drying in which the treatment liquid is IPA (isopropanol) is used in batch treatment or single-wafer treatment in a drying module.

On the other hand, "Precision Cleaning Equipment and Latest Applied Technology", Industrial Material Center, issued November 8, 1991, P416
And P417 describe steam cleaning methods. In the steam cleaning method, the solvent (treatment liquid) in the steam cleaning tank with the condensing coil attached to the upper part of the tank is heated and boiled to form a vapor layer below the condensing coil, and the object to be cleaned is placed in this vapor layer. And wash.

[0005]

As described in the above literature, as one of the techniques for drying a wafer,
There is a vapor drying technology. In a vapor dryer, a treatment liquid such as IPA (isopropanol) contained in a vapor tank is heated to be vaporized, and a wafer is applied to the IPA vapor (vapor) to perform drying. IP condensed on the wafer surface
The A vapor contains a large amount of water and contains the treatment liquid (IPA
Liquid). By the way, the present inventor has clarified that the following inconvenience may occur in the vapor drying of the wafer in the manufacture of the semiconductor device, and the density of the oxide film defects on the wafer surface may increase. That is, when the object to be treated is put in the vapor tank, the temperature is lowered and the vapor layer (vapor layer) is temporarily lowered. Then, while the vapor layer rises again and the object to be processed is covered with the vapor, the wafer is exposed to air at a high temperature of around 80 ° C., so that the moisture adhering to the surface of the wafer causes oxidation. It takes tens of seconds for the wafer to be covered with the vapor layer. Further, the above-mentioned oxidation appears as a watermark or a blur in appearance.

An object of the present invention is to provide a vapor processing apparatus in which the surface of an object to be processed is less likely to be oxidized. The above and other objects and novel features of the present invention will be apparent from the description of the present specification and the accompanying drawings.

[0007]

The outline of the representative ones of the inventions disclosed in the present application will be briefly described as follows. That is, the vapor drying apparatus of the present invention has a vapor tank for storing a treatment liquid in the lower portion and having a cooling spiral tube in the upper portion, a vaporizer for vaporizing the treatment liquid in the vapor tank, and the vapor tank. A vapor drying apparatus having a loader for loading and unloading an object to be processed into and from an upper processing steam, wherein an injection apparatus for spraying a processing liquid onto the object to be processed carried into the vapor tank is provided. Further, the injection device is provided with a heater for heating the processing liquid, and is configured to inject the vapor onto the object to be processed. Further, the vapor composed of the treatment liquid is sprayed toward the object to be treated when the object to be treated is put in the vapor tank.

[0008]

According to the above-mentioned means, the vapor drying apparatus of the present invention is adapted to inject the vapor of the treatment liquid onto the object to be treated contained in the vapor tank. For this reason, even if there is a decrease in the vapor layer that occurs when the object to be treated is placed in the vapor tank, the surface of the object to be treated is covered with the sprayed vapor, and this vapor is replaced with moisture to dry the vapor. As a result, the surface of the object to be treated is less likely to be oxidized. When the object to be processed is a wafer, the defect density of the oxide film can be reduced by suppressing the oxidation.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a sectional view showing an outline of a vapor drying apparatus according to an embodiment of the present invention, and FIG. 2 is a graph showing steam temperature recovery characteristics. Vapor drying device 1 of the present invention
Has a vapor tank 3 as shown in FIG. This vapor tank 3 has a box-shaped structure with an open top. An opening door (not shown) having a double door shape is provided in this opening. Further, the treatment liquid 10, for example, the isopropanol (IPA) liquid 10 is accommodated in the vapor tank 3 to an intermediate depth. The IPA liquid 10 is pressure-fed and supplied from a liquid supply pipe 9 attached to one side of the vapor tank 3. Also,
On the bottom side of the vapor tank 3, a vaporizing device for vaporizing the IPA liquid 10, for example, a heater 11 is provided.
The heater 11 heats and vaporizes the IPA liquid 10 in the vapor tank 3 (the boiling point of the IPA liquid 10 is 82 ° C.). Then, the object to be processed 1 is evaporated by the vaporized vapor (IPA vapor 6).
Steam dry 2.

In this embodiment, the object to be processed 12 is the wafer 1
It becomes 2. The wafer 12 is placed in a cassette 20 upright. The cassette 20 is held by the loader 5 and placed in the vapor tank 3, and when the vapor drying is completed, the vapor tank 3 is placed.
Taken out from. The loader 5 holds and releases the cassette 20 by opening and closing the pair of clamp claws 22.

On the other hand, on the inner wall of the upper portion of the vapor tank 3, a cooling flexible tube 2 is provided over a certain height range. Since the cooling water is caused to flow through the cooling spiral pipe 2, the opening space of the vapor tank 3 is cooled. Due to this, IP has risen
When the A vapor 6 reaches the space area cooled by the cooling spiral tube 2, it condenses and descends. Therefore, the vapor layer 17 is generated in the height part of the vapor tank 3. This vapor layer 1
The space area where 7 exists is the processing area, and the wafer 12 is dried.

Below the vapor layer 17, a tray 7 for receiving the waste liquid 16 condensed on the surface of the wafer 12 and falling is arranged. A waste liquid pipe 8 is connected to the liquid collecting portion 15 in the central portion of the tray 7. The waste liquid pipe 8 is guided to the outside of the vapor tank 3 and drops into the tray 7
Is discharged to the outside of the vapor tank 3.

Further, this is one of the features of the present invention, and the vapor tank 3 is provided with an injection device 30. The ejection device 30 includes an ejection nozzle 4 and the ejection nozzle 4
And a heater 32 for heating the supply pipe 31, and an IPA inside the supply pipe 31.
And a pump 33 for pumping the liquid. The other end of the supply pipe 31 is connected to a tank or the like (not shown) that stores the IPA liquid that is a processing liquid. By driving the pump 33 and operating the heater 32, the IPA vapor 13 is sprayed from the tip of the injection nozzle 4 toward the wafer 12. This spraying (injection) is performed at least during the time when the cassette 20 is put in the vapor tank 3 and the vapor layer 17 starts descending due to the temperature decrease, and then the vapor layer 17 returns to the upper position again. FIG. 2 is a graph showing vapor temperature recovery characteristics in the vapor dryer of the present invention and the conventional vapor dryer. As can be seen from the graph, in the conventional vapor drying apparatus, when the cassette 20 is placed in the vapor tank 3, the temperature of the vapor tank 3 drops, and it takes a long time until the temperature returns to the original state again. However, in the case of the vapor drying apparatus of the present invention, when the cassette 20 is put into the vapor tank 3, the vapor state I from the jet nozzle 4 of the jet apparatus 30 is injected.
Since the PA injection liquid 13 is sprayed onto the wafer 12 in the cassette 20, the temperature drop is small and the vapor temperature recovery time is short. That is, the wafer 12 is used in the vapor tank 3
When it is put into the inside of the vapor tank 3, it is exposed to the IPA vapor, and the vapor drying process is performed from the moment of putting it into the vapor tank 3 until it is taken out.
Oxidation due to moisture adhering to the surface of 2 becomes difficult to occur. Also, since the steam temperature recovery time is shortened,
It is also possible to shorten the vapor drying processing time.

In such a vapor dryer 1,
When the cassette 20 is put into the vapor tank 3 by the loader 5, the injection device 30 operates to spray the vaporized IPA injection liquid 13 onto the wafer 12 in the cassette 20.
When the cassette 20 is put into the vapor layer 17 of the vapor tank 3, the vapor layer 17 is lowered due to the temperature drop. In the conventional case, since the wafer 12 is heated here without coming into contact with the IPA vapor 6, oxidation progresses due to water adhering to the surface of the wafer 12, and watermarks and blurring occur
In the case of the present invention, the IPA injection liquid 13 is injected from the injection nozzle 4.
Are sprayed onto the wafer 12, the surface of the wafer 12 is covered with the IPA jetting liquid 13, and the vapor drying process starts before the oxidation progresses. Moreover, since the vaporized IPA injection liquid 13 is injected from the injection nozzle 4, the temperature recovery time is shortened, and the vapor drying process is effectively performed. Then, the cassette 20 is carried out of the vapor tank 3 by the loader 5, and one batch process is completed.

[0015]

【The invention's effect】

(1) The vapor drying device of the present invention has an injection device, and when the wafer is put in the vapor tank, the vaporized IPA injection liquid is sprayed toward the wafer, so the surface of the wafer has a high temperature. In this state, there is no contact with air, and there is an effect that oxidation due to moisture adhering to the surface of the wafer does not occur.

(2) According to the above (1), in the vapor drying apparatus of the present invention, since the wafer put in the vapor tank is covered with the vaporized IPA injection liquid, the vapor drying process is immediately performed. The effect is obtained.

(3) According to the above (1), in the vapor drying apparatus of the present invention, when the wafer is put in the vapor tank, the vaporized IPA injection liquid is sprayed toward the wafer, so that the inside of the vapor tank is The temperature recovery time is shortened, and the time for covering the wafer with the entire vapor layer is shortened.

(4) According to the above (2) and (3), in the vapor drying apparatus of the present invention, the wafer is vapor-dried as soon as the wafer is placed in the vapor tank, and the vapor temperature recovery time is short. Therefore, it is possible to obtain an effect that an effective vapor drying process can be performed.

(5) According to the above (2) and (3), in the vapor drying apparatus of the present invention, the wafer is vapor-dried as soon as the wafer is put in the vapor tank, and the vapor temperature recovery time is short. Therefore, it is possible to obtain the effect that the vapor drying processing time can be shortened.

(6) Due to the above (1) to (5), according to the present invention, it is possible to provide a vapor drying device capable of suppressing the oxidation of the wafer and performing an effective treatment in a short time. Is obtained.

Although the invention made by the present inventor has been specifically described based on the embodiments, the invention is not limited to the above embodiments, and various modifications can be made without departing from the scope of the invention. Needless to say, for example,
Although the treatment liquid is heated by the heater to be vaporized in the above embodiment, the treatment liquid may be vaporized by ultrasonic vibration. Further, other chemicals may be used as the processing liquid. Further, the IPA injection liquid 13 injected from the injection nozzle 4 of the injection device 30 does not have to be vaporized by the heater 32. Since the IPA liquid is volatile, if it adheres to the surface of the wafer 12, it will be vapor-dried due to its volatility.

In the above description, the invention made by the present inventor was mainly applied to a vapor drying apparatus using isopropanol as a processing liquid, which is the field of application in the background, but the invention is not limited thereto. It can also be applied to, for example, a vapor dryer using chlorofluorocarbon. Further, the present invention can be similarly used as a vapor cleaning device. The present invention can be applied to at least a vapor processing apparatus.

[Brief description of drawings]

FIG. 1 is a sectional view showing an outline of a vapor drying apparatus according to an embodiment of the present invention.

FIG. 2 is a graph showing vapor temperature recovery characteristics in the vapor dryer of the present invention and the conventional vapor dryer.

[Explanation of symbols]

1 ... Vapor dryer, 2 ... Cooling pipe, 3 ... Vapor tank,
4 ... Injection nozzle, 5 ... Loader, 6 ... Steam (IPA vapor), 7 ... Saucepan, 8 ... Waste liquid pipe, 9 ... Liquid supply pipe, 10 ...
Processing liquid (IPA liquid), 11 ... Heater, 12 ... Processing object (wafer), 13 ... IPA injection liquid, 15 ... Liquid collecting part, 16
... waste liquid, 17 ... vapor layer, 20 ... cassette, 22 ... clamp part, 30 ... injection device, 31 ... supply pipe, 32 ... heater, 33 ... pump.

Claims (3)

[Claims] 1. A vapor tank having a cooling spiral tube in an upper portion and containing a treatment liquid in a lower portion, a vaporizer for vaporizing the treatment liquid in the vapor tank, and a treatment vapor in an upper portion of the vapor tank. A vapor treatment apparatus having a loader for loading and unloading the object to be treated, wherein the vapor is provided with an injection device for spraying a treatment liquid onto the object to be treated carried into the vapor tank. Processing equipment. 2. The vapor processing apparatus according to claim 1, wherein the injection apparatus is provided with a heater for heating the processing liquid, and injects vapor onto the object to be processed. 3. The vapor processing apparatus according to claim 1, wherein the object to be processed is dried with steam.