JP2567703Y2 - Steam drying equipment - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a steam drying apparatus used for removing water adhering to the surface of semiconductor substrates, electronic parts, optical parts, precision machined parts, etc. after precision cleaning and surface processing. It is about.

[0002]

2. Description of the Related Art Conventionally, a steam drying apparatus of this kind stores a liquid such as a hydrophilic organic solvent such as isopropyl alcohol at the bottom of a container, and heats the liquid from the bottom to generate steam. It is dried by substituting the water adhering to the surface of the object to be dried held in the above.

[0003]

According to the conventional steam drying apparatus, the upper part of the container is open, and several cooling coils are provided so that the vapor of the solvent does not leak from the upper part. It is liquefied and put back in the container, but it is said to be not perfect. If isopropyl alcohol vapor leaks from the upper part of the container, it is not only unfavorable for sanitation, but the flash point of the vapor is 21.1 ° C. and the ignition point is 460.
There is a high risk of fire as can be seen from the figures such as ° C and the explosion range of 2 to 12 Vol%. Also, when the object to be dried is put into the container, if pure water adhering to the surface of the object to be dried falls into the isopropyl alcohol stored at the bottom and mixes with the isopropyl alcohol, it becomes an impurity, and the evaporation temperature is deviated. If the water is evaporated and the water evaporates and adheres to the object to be dried, the drying effect is hindered.

SUMMARY OF THE INVENTION The present invention has been made to solve such a conventional problem. The present invention prevents the vapor of isopropyl alcohol or the like from leaking from the upper part of the container and prevents the water falling from the object to be dried from an organic substance such as isopropyl alcohol. It is an object of the present invention to provide a steam drying device which is prevented from being mixed in a solvent.

[0005]

Means for Solving the Problems As means for technically solving this problem, the present invention is directed to a closed container having a lid for storing a material to be dried, and a narrow slit provided on a side portion of the closed container. A gist comprising a steam generating container communicating with the closed container through a hole, a heater provided on the outer peripheral portion of the closed container and the steam generating container, and a jig for holding the object to be dried. is there. Further, the gist of the present invention is that the entire steam drying apparatus is sealed with a casing, and a gas concentration sensor for detecting a gas leakage abnormality is provided in the casing.

[0006]

[Operation] The container for storing the objects to be dried has a sealed structure, so that vapors such as isopropyl alcohol do not leak from the upper part of the container, thereby preventing the adverse effects on the human body and preventing the danger of fire. can do. Since the steam generating container is attached to the side of the closed container, even when moisture is dropped when the object to be dried is stored in the closed container, it does not enter the organic solvent such as isopropyl alcohol. Furthermore, if the entire steam drying device is sealed with a casing, a double hermetic structure can be achieved to completely prevent the leakage of steam such as isopropyl alcohol, and the casing has a gas concentration for detecting a gas leak abnormality. Even if a gas leak occurs due to the provision of the sensor, danger can be avoided by the gas concentration sensor.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below in detail with reference to the accompanying drawings. In FIG. 1, reference numeral 1 denotes a sealed container made of stainless steel or quartz having a lid 2 on an upper part, and the inner surface is subjected to electrolytic polishing or Teflon coating. The lid 2 is also made of stainless steel or quartz, the inner surface of which is subjected to electrolytic polishing or Teflon coating, the packing 3 is attached concentrically on the lower surface side, and the air between the packings is sucked by the vacuum valve 4. When the closed container 1 is covered, it is brought into close contact with its flange.

Reference numeral 5 denotes a small steam generating vessel made of quartz, which is attached to a plurality of sides of the closed vessel 1 and communicates with the closed vessel 1 through a narrow slit 1a. Each steam generating vessel 5 is connected with a supply pipe 6 for supplying a solvent such as isopropyl alcohol, and is provided with an opening / closing valve 7.

Reference numeral 8 denotes a heater, which is attached so as to cover the outer peripheral surface of the closed vessel 1, a heater 9 is also attached to the outer peripheral face of the steam generating container 5, and a heater is also provided on the upper surface side of the lid 2. 10 is installed.
Furthermore, temperature sensors 1 are provided at key points of each heater 8, 9 and 10.
1, 12, and 13 are provided, respectively.

Numeral 14 denotes a jig for holding an object to be dried 15 such as a semiconductor wafer. A jig 16 is attached to the bottom of the jig. The jig 14 can be fixed by being locked to the bar 17. At this time, the upper end of the floating bar 17 is
And can be held in a state where it is slightly raised from the jig 14.

Reference numeral 18 denotes an exhaust duct connected to the bottom of the closed container 1. An exhaust valve 19 is provided near the communication port to the closed container 1, and the end of the exhaust duct 18 is connected to a gas scrubber 20. Have been.

The gas scrubber 20 has a filler 21 therein.
The upper part is provided with a shower nozzle 22 and a water supply pipe 23 connected thereto. The water supply pipe 23 is provided with an opening / closing valve 24.

Reference numeral 25 denotes a drain trap connected to the bottom of the closed vessel 1; 26, a nitrogen gas supply pipe connected to the top of the closed vessel 1;

The steam drying apparatus according to the present invention is configured as described above. To use the steam drying apparatus, first, the closed vessel 1 is preheated by the heater 8 and the temperature in the closed vessel 1 is set to 85 ° C. to 9 ° C.
The container is warmed to 0 ° C., the object to be dried 15 is held and fixed in the closed container 1 via the jig 14, the lid 2 of the closed container 1 is closed, and the air between the packings 3 is suctioned by the vacuum valve 4. Adhere to 1. The lid 2 is also heated to an appropriate temperature by the heater 10.

When the object to be dried 15 is stored in the closed container 1, even if the water adhering to the surface falls as water droplets, the water droplets may not enter the isopropyl alcohol in the steam generating container 5. In addition, since a drain pipe is attached to the bottom of the sealed container 1 below the jig 14, the water drops are drained through the drain pipe.
Therefore, isopropyl alcohol is not used as an impurity.

Next, isopropyl alcohol is supplied into each steam generating vessel 5 from the supply pipe 6 in an amount required for drying, and heated by the heater 9 to generate steam.
The vapor of the isopropyl alcohol blows out from the narrow slit hole 1a into the closed container 1 and fills in order from the bottom. When the vapor comes into contact with the object 15 to be dried, the vapor is replaced with water adhering to the surface thereof. The surface of the object to be dried 15 is dried and covered with isopropyl alcohol.

At this time, the temperature inside the sealed container 1 is controlled by the temperature sensor 11, and the temperature control accompanying the generation of steam is performed by the temperature sensor 12. These temperature controls were very important because they had a significant effect on the dry finish.

After confirming that the surface of the object to be dried 15 has been completely replaced by the vapor of isopropyl alcohol, the exhaust valve 19 is opened, and the open / close valve is opened.
When the air is exhausted while introducing nitrogen gas into the closed vessel 1 with opening 27, the isopropyl alcohol adhering to the surface of the object 15 to be dried can be evaporated and dried.

When exhausting the isopropyl alcohol gas, the isopropyl alcohol gas is discharged to the outside from the exhaust port 20a through the gas scrubber 20 because it is dangerous. The gas scrubber 20 opens the opening / closing valve 24 and blows out water in a shower shape with a shower nozzle 22, and the water flows through the filler 21,
It is discharged outside from 20b. The role of the gas clubber 20 is to lower the gas concentration by dissolving isopropyl alcohol gas exhausted from the inside of the closed container 1 through the filler 21 and dissolving it in water from the shower nozzle 22. It becomes possible to exhaust.

After the drying is completed, a small amount of air is supplied between the packings 3 of the lid 2 to release the close contact, the lid 2 is opened, and the object 15 to be dried together with the jig 14 is taken out of the closed vessel 1. .

As another embodiment of the present invention, the entire drying device is closed by a casing 28 as shown by a phantom line in FIG.
A gas concentration sensor 29 for detecting a gas leak abnormality is provided in the casing. In this case, even when there is a slight gas leak, an abnormality can be notified by the gas concentration sensor 29.

Further, in order to prevent gas leakage from the lid 2, an exhaust pipe (not shown) may be connected between the packings 3 so that the isopropyl alcohol gas does not leak outside through the vacuum valve 4. is there. The gas scrubber 20 can be placed inside the casing 28 in addition to being placed outside. However, the isopropyl alcohol gas from the exhaust port 20a of the gas scrubber 20 and the drainage from the drain port 20b are discharged to the outside of the casing 28.

[0023]

[Effects of the Invention] As described above, according to the present invention,
Since the container for storing the drying object is completely sealed, gas such as isopropyl alcohol does not leak to the outside, preventing harmful effects on the human body and preventing fire hazards. Play. In addition, since the steam generating container is attached to the side of the closed container, even if moisture adhered to the surface of the object to be dried is dropped when the object to be dried is stored in the closed container, it is not mixed into the steam generating container. Therefore, isopropyl alcohol or the like does not become an impurity, and the drying operation can be reliably performed while keeping the evaporation temperature constant.

[Brief description of the drawings]

FIG. 1 is an explanatory view showing an embodiment of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Airtight container 1a ... Slit hole 2 ... Lid 3 ...
Packing 4 ... Vacuum valve 5 ... Steam generating vessel
6 ... supply pipe 7 ... opening and closing valve 8, 9, 10 ... heater 11, 12, 13 ... temperature sensor 14 ... jig 15 ...
Material to be dried 16 ... Sink 17 ... Floating bar 18 ...
Exhaust duct 19 ... Exhaust valve 20 ... Gas scrubber
21 ... Filler 22 ... Shower nozzle 23 ... Water supply pipe
24 ... open / close valve 25 ... drain trap 26 ... nitrogen gas supply pipe 27 ... open / close valve 28 ... casing 29 ... gas concentration sensor

Claims (2)

(57) [Scope of request for utility model registration] 1. An airtight container with a lid for storing an object to be dried, a steam generating container communicating with the airtight container through a thin slit hole provided on a side portion of the airtight container, the airtight container and the steam generating container A steam drying apparatus, comprising: a heater provided on an outer peripheral portion of the device; and a jig for holding the object to be dried. 2. The steam drying apparatus according to claim 1, wherein the entire steam drying apparatus is sealed by a casing, and a gas concentration sensor for detecting a gas leakage abnormality is provided in the casing.