JPH11337263A - Apparatus and method for drying carrier box - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent attachment of particles and generation of drying unevenness, and perform drying in a short time, by dipping a carrier box for a given time into an organic solvent in a dipping tank, of which temperature is controlled to have not more than a specific temperature, and subsequently drying the carrier box after being lifted up from the organic solvent. SOLUTION: A carrier box 14 is dipped into isopropyl alcohol 20 in a dipping tank 22 by means of a vertical movement mechanism 64. At this moment, the temperature of isopropyl alcohol 20 is controlled to be 60 deg.C or lower. Subsequently, the carrier box is lifted up from the dipping tank 22 by the vertical movement mechanism 64 and transferred to a drying standby portion 30 by means of a horizontal guide mechanism 60, and after completion of the drying treatment, lifted up by the vertical movement mechanism 64. Thus, moisture on the surface of the carrier box 14 is replaced with isopropyl alcohol 20, and the particles are removed prior to evaporation, thereby eliminating drying unevenness.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a carrier box drying apparatus used for drying after cleaning a carrier box used for shipping a work such as a semiconductor silicon single crystal wafer (hereinafter sometimes referred to as a wafer) and the like. And a method for washing and drying the carrier box.

[0002]

2. Related Art At present, a semiconductor silicon single crystal wafer used for a semiconductor device or the like is generally packed in a plastic carrier (transport) box and shipped.

As the degree of integration of semiconductor devices increases, regulations (specifications) on the size and quantity of particles adhering to a wafer have become strict. In addition, the attachment of organic substances to wafers due to elution from plastics has also been restricted. In order to satisfy such specifications, the carrier box is being cleaned as a measure to prevent dust generation from the carrier box.

That is, the carrier box is cleaned to remove dust (particles) adhered to the carrier box. After cleaning with a chemical solution, rinsing is performed sufficiently, and the wafer is dried, loaded with wafers, and shipped. Is common.

As a drying method, the carrier box is dried in a clean oven by circulating warm air while maintaining the inside of the oven at about 60 ° C., or a rotating mechanism incorporated in the unit as a cleaning device for the carrier box. Is rotated in an apparatus equipped with a device, and clean warm air is blown onto the device, and dried by so-called spin.

[0006] The dried carrier box is inspected before use for the adhesion state of particles and the carrier box for uneven drying.

[0007] Here, the drying unevenness is inspected because it has a possibility of becoming a medium for dissolving the organic matter from the plastic described above.

In the current drying method, uneven drying may occur on the inner surface of the groove in which the wafer enters the carrier box, and the drying method using circulation of warm air has a disadvantage that the time required for drying is long.

[0009]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems of the prior art. In drying the carrier box, there is no adhesion of particles, no drying unevenness occurs, and the drying time is short. An object of the present invention is to provide a carrier box drying apparatus and method that can be dried and a carrier box cleaning / drying method.

[0010]

In order to solve the above-mentioned problems, a drying apparatus for a carrier box according to the present invention comprises an immersion tank containing an organic solvent and having a temperature control means for controlling the temperature of the organic solvent. The carrier box is immersed in an organic solvent whose temperature is controlled to 60 ° C. or lower in the immersion tank for a predetermined time, and then the carrier box is pulled up from the organic solvent and dried.

The organic solvent in the immersion tank is heated to 50 ° C. to 60 ° C.
It is more preferable to control the temperature within the above range. If the temperature exceeds 60 ° C., there is a disadvantage that the carrier box made of plastic is thermally deformed. On the other hand, if the temperature is lower than 50 ° C., it takes a long time to dry due to the use of the evaporation effect of the organic solvent. There is a disadvantage.

A drying standby unit is provided near the immersion tank,
It is preferable that the carrier box pulled up from the organic solvent is placed on the drying standby section and dried.

[0013] If the drying standby section is constituted by a flat plate member extending laterally from the upper edge of one side wall of the immersion tank, the carrier box immersed in an organic solvent in the immersion tank. This is very suitable because it can be immediately placed on the drying standby section after the sheet is pulled up.

A liquid level controller is provided in the immersion tank,
If the liquid level of the organic solvent is controlled by the liquid level control device so that the liquid level of the organic solvent in the immersion tank is always located above the upper end of the carrier box in which the organic solvent is immersed, the carrier box is Therefore, inconveniences such as uneven drying can be avoided.

The immersion tank is further provided with a transport means for transporting the carrier box movably up and down, the carrier box is immersed in the organic solvent in the immersion tank by the transport means, and then pulled up and placed on the drying standby unit. Then, it is preferable to carry out each operation of transporting to the next step after drying, because the efficiency and automation of the processing can be improved.

The method for drying a carrier box according to the present invention comprises:
The carrier box is immersed in an organic solvent whose temperature is controlled within a temperature range of 60 ° C. or lower for a predetermined time, pulled up, and then left in a clean air to be dried.

In the method for drying a carrier box according to the present invention, the carrier box is immersed in an organic solvent, pulled up, and left in clean air by the carrier box drying apparatus to efficiently perform the drying process. Can be.

The method for cleaning and drying a carrier box according to the present invention includes a water rinsing step of rinsing the carrier box with pure water, a chemical cleaning step of cleaning the water-rinsed carrier box with a chemical, and a carrier cleaning with the chemical. The finishing water rinsing step of rinsing the box again with pure water, and the carrier box rinsed with the finishing water is immersed in an organic solvent temperature-controlled to a temperature range of 60 ° C. or lower for a predetermined time, pulled up, and left in clean air. And drying.

In the method for cleaning and drying a carrier box of the present invention, the drying step can be efficiently performed by performing the drying step in the above-described drying apparatus for the carrier box.

As the above-mentioned organic solvent, isopropyl alcohol is preferably used, but methanol, ethanol, acetone, cyclohexane, methylene chloride and the like can also be used.

[0021]

Embodiments of the present invention will be described below with reference to the accompanying drawings. FIG. 1 is a schematic side view of a carrier box drying apparatus according to the present invention.

In FIG. 1, reference numeral 12 denotes a carrier box drying apparatus of the present invention, which is a drying apparatus main body 16 for drying the carrier box 14 and a carrier box 14 provided above the drying apparatus main body 16 for transporting the same. And a carrier box conveying means 18.

The drying apparatus main body 16 has an immersion tank containing an organic solvent, for example, isopropyl alcohol 20, that is, an IPA immersion tank 22. Reference numeral 24 denotes an indirect heater, which is constituted by a number of heating rods 24a installed below the bottom plate 22a of the IPA immersion tank 22.

Reference numeral 26 denotes a temperature control device connected to the indirect heater 24. The temperature control device 26 turns on and off the indirect heater 24 according to a temperature signal from a temperature sensor 28 provided in the IPA immersion tank 22, and controls the isopropyl alcohol 20 contained in the IPA immersion tank 22 to a predetermined value. Temperature can be controlled.

Numeral 30 denotes a drying standby section constituted by a plate-like member, and one short side wall 2 of the IPA immersion tank 22.
2b is provided to extend laterally from the upper edge. The drying standby section 30 is a place where the carrier box 14 immersed in the isopropyl alcohol 20 in the IPA immersion tank 22 is placed for a predetermined time after being lifted. Reference numeral 32 denotes a drainage discharge pipe that discharges the drainage retained in the drying standby unit 30. Reference numeral 34 denotes a valve for opening and closing the drainage pipe 32. Reference numeral 35 denotes an outer side wall provided on the outer edge of the drying standby unit 30.

Reference numeral 36 denotes a supply pipe for supplying isopropyl alcohol 20 to the IPA immersion tank 22, which is attached to the other tall side wall 22c of the IPA immersion tank 22. A control valve 38 is attached to the supply pipe 36. The control valve 38 is electrically connected to a low level sensor 40 and a high level sensor 42.

When the liquid level of the isopropyl alcohol 20 drops and is detected by the low liquid level sensor 40, the control valve 38 is opened by a signal from the low liquid level sensor 40, and the isopropyl alcohol 20 is released from the IPA. Immersion tank 22
Supplied within.

On the other hand, when the liquid level of the isopropyl alcohol 20 rises and is detected by the high liquid level sensor 42, the control valve 38 is closed by a signal from the high liquid level sensor 42, and the IPA of the isopropyl alcohol 20 is closed. Immersion tank 22
Supply to the interior is stopped.

As shown in FIG. 1, the low liquid level sensor 40
Is installed above the upper surface of the carrier box 14 so that the entire carrier box 14 is always immersed in the isopropyl alcohol 20 so that inconvenience such as uneven drying is not caused. I have.

A circulation pipe 44 through which cooling water circulates is provided at the upper end of the other side wall 22c and the upper end of the outer side wall 35 of the drying standby section 30. Drying device main body 1 including IPA immersion tank 22 and drying standby unit 30
The atmosphere around the upper end of the container 45 constituting 6 is cooled by the circulation of the cooling water.

Therefore, when the isopropyl alcohol in the IPA immersion tank 22 or the isopropyl alcohol dropped into the drying standby unit 30 evaporates and escapes upward, the isopropyl alcohol vapor approaching the cooling water circulation pipe 44 Are aggregated. The agglomerated liquid isopropyl alcohol is applied to the lower side wall 22 of the circulation pipe 44.
It is collected inside the receiving groove 46 projecting from the inner surfaces of b and 22c, and is discharged and collected from the collecting pipe 48 communicating with the receiving groove 46. Reference numeral 50 denotes an opening / closing valve for opening and closing the collection pipe 48. 52 is a supply pipe for supplying cooling water to the circulation pipe 44, 54 is a valve for opening and closing the supply pipe 52, 56 is a discharge pipe for discharging cooling water from the circulation pipe 44, and 58 is A valve for opening and closing the discharge pipe 56.

The carrier box transport means 18 has a horizontal guide mechanism 60 for horizontal movement provided above the container 44. The horizontal guide mechanism 60 includes a box carrier 62 for housing the carrier box 14 therein.
Are vertically movably suspended via a vertical movement mechanism 64.

The horizontal guide mechanism 60 and the vertical movement mechanism 64
The box carrier 62 accommodating the carrier box 14 is transferred from the previous process by operating
It is immersed in isopropyl alcohol 20 in the PA immersion tank 22, then pulled up, and further placed on the drying standby unit 30,
After the completion of the drying process, it can be transported to the next step.

The operation of the above-described carrier box drying apparatus 12 and the method of drying the carrier box will be described.

The carrier box 14 housed in the box carrier 62 is first rinsed with pure water in a water rinsing step, then washed with a chemical in a chemical cleaning step, and rinsed again with pure water in a finish water rinsing step.
After such a pre-process, the box carrier 62 accommodating the carrier box 14 is moved by the horizontal guide mechanism 60 to the IPA immersion tank 2 of the carrier box drying apparatus main body 16.
2 is transported above.

The carrier box 14 is immersed in the isopropyl alcohol 20 in the IPA immersion tank 22 by the vertical movement mechanism 64. At this time, the temperature of isopropyl alcohol is controlled to 60 ° C. or less. If the temperature is higher than 60 ° C., the plastic carrier box 14 is not suitable because it deforms. However, if the temperature is too low, the drying takes too much time, so a temperature range of 50 ° C to 60 ° C is suitable.

The carrier box 14 immersed in the isopropyl alcohol 20 in the IPA immersion tank 22 is then lifted out of the IPA immersion tank 22 by a vertical movement mechanism 64, and then dried by a horizontal guide mechanism 60. 30 and is placed on the drying standby unit 30 by the vertical movement mechanism 64. When the drying process is completed, the sheet is lifted upward by the vertical movement mechanism 64, and is conveyed to the next step by the horizontal guide mechanism.

As described above, by immersing the carrier box 14 in the isopropyl alcohol 20 in the IPA immersion tank 22 (typically for about 1 to 3 minutes), the water on the surface of the carrier box 14 is
, And the particles are removed before the isopropyl alcohol 20 evaporates.
Is completely evaporated, thereby eliminating drying unevenness.

[0039]

EXAMPLES Next, the method of the present invention will be described more specifically with reference to examples.

Example 1 The carrier box was washed and dried in the following procedure. 1. Water rinsing step with pure water: This step is performed to remove large dust adhering to the surface of the carrier box. 2. Chemical cleaning step: The cleaning brush is used to clean all corners of the carrier box, such as the grooves. 3. Finishing water rinsing step using pure water: This step is performed to wash off the chemical solution and the like in the previous step. 4. Immersion drying with isopropyl alcohol: Using the carrier box drying device 12 shown in FIG. 1, the temperature of isopropyl alcohol is controlled in the range of 50 ° C. to 60 ° C., and the substrate is immersed in isopropyl alcohol for 2 minutes. The time until the sample was placed and dried was measured.

The properties of the carrier box subjected to the above-mentioned drying treatment were as follows. Particle adhesion carrier box: 0 boxes / 1000
Box Drying unevenness: 0 boxes / 1000 boxes Drying time: 5 minutes / 1 box

As is apparent from the results, according to the method of the present invention, particles can be completely removed, and a very good drying treatment can be performed without drying unevenness and short drying time. Was confirmed.

Further, since the immersion temperature of isopropyl alcohol was as low as 50 ° C. to 60 ° C., no deformation of the carrier box was observed, and the occurrence rate of scratches (flaws) due to the deformation of the wafer insertion groove was zero in the visual inspection. % And good results were obtained.

(Comparative Example 1) A carrier box was washed and dried by a conventional method. The procedure of this conventional method is the same as the procedures 1 to 3 of the embodiment 1. Instead of the immersion drying with isopropyl alcohol in the procedure 4 of the embodiment 1, the carrier is dried in a clean drier and the water on the surface of the carrier box is evaporated. Then, the drying time until endurance was measured. The properties of the dried carrier box were as follows. Particle adhesion carrier box: 5 boxes / 1000
Box Drying unevenness: 6 boxes / 1000 boxes Drying time: 45 minutes / 1 box

As is apparent from the results, it is difficult to completely remove the particles and to completely suppress the drying unevenness in the conventional method, and further, the drying time is long. It turns out that it is much inferior compared with.

In the embodiments and examples of the invention described above, examples were given in which isopropyl alcohol was used as the organic solvent. However, other organic solvents, for example, methanol, ethanol, acetone, cyclohexane, methylene chloride and the like were used. Can also.

[0047]

As described above, according to the present invention, when the carrier box is dried, there is achieved a great effect that no particles adhere, no drying unevenness occurs, and drying can be performed in a short time. .

[Brief description of the drawings]

FIG. 1 is a schematic side view of a carrier box drying apparatus of the present invention.

[Explanation of symbols]

12: Carrier box drying device, 14: Carrier box, 16: Drying device main body, 18: Carrier box conveying means, 20: Organic solvent or isopropyl alcohol,
22: immersion tank or IPA immersion tank, 22a: bottom plate, 22
b, 22c: side wall, 24: indirect heater, 24a: heating rod, 26: temperature control device, 28: temperature sensor, 3
0: drying standby unit, 32: drainage discharge pipe, 34: valve, 35: external side wall, 36: supply pipe, 38: control valve, 40: low liquid level sensor, 42: high liquid level sensor, 4
4: circulation pipe, 45: container, 46: receiving groove, 48: collection pipe, 50: open / close valve, 52: supply pipe, 5
4: valve, 56: discharge pipe, 58: valve, 60:
Horizontal guide mechanism, 62: box carrier, 64: vertical movement mechanism.

Claims (12)

[Claims] 1. An immersion tank containing an organic solvent and provided with a temperature control means for controlling the temperature of the organic solvent, wherein the carrier box is moved to an organic solvent whose temperature is controlled to 60 ° C. or less in the immersion tank. An apparatus for drying a carrier box, wherein the carrier box is immersed for a predetermined time, and then the carrier box is pulled up from the organic solvent and dried. 2. The method according to claim 1, wherein the organic solvent in the immersion tank is heated to 50.degree.
2. The drying apparatus for a carrier box according to claim 1, wherein the temperature is controlled within a temperature range of ° C. 3. A drying standby unit is provided adjacent to the immersion tank, and the carrier box pulled up from an organic solvent is placed on the drying standby unit and dried. 3. The drying device for a carrier box according to 2. 4. The drying standby section according to claim 3, wherein the drying standby section is constituted by a flat plate member provided to extend laterally from an upper edge of one side wall of the immersion tank. Drying device for carrier box. 5. A liquid level control device is provided in the immersion tank, and the liquid level control device controls the liquid level of the organic solvent in the immersion tank so that the liquid level is always above the upper end of the carrier box in which the liquid is immersed. The drying device for a carrier box according to any one of claims 1 to 4, wherein a liquid level of the organic solvent is controlled. 6. A transport means for transporting the carrier box movably up and down is provided, and the carrier box is immersed in the organic solvent in the immersion tank, pulled up, placed on a drying standby unit, and dried. After that, each operation of transporting to the next process is performed.
The drying device for a carrier box according to any one of claims 5 to 10. 7. The carrier box drying apparatus according to claim 1, wherein the organic solvent is isopropyl alcohol. 8. A carrier box, wherein the carrier box is immersed in an organic solvent whose temperature is controlled at a temperature of 60 ° C. or lower for a predetermined time, lifted up, and then left in clean air to be dried. Drying method. 9. The method according to claim 1, wherein the carrier box is immersed in an organic solvent, pulled up, and left in clean air.
9. The method for drying a carrier box according to claim 8, wherein the drying is performed by the drying apparatus for a carrier box according to any one of claims to 7. 10. A water rinsing step of rinsing the carrier box with pure water, a chemical liquid washing step of cleaning the water-rinsed carrier box with chemical liquid, and a finish of rinsing the chemical liquid washed carrier box again with pure water. A water rinsing step, and a step of immersing the carrier box rinsed with finish water in an organic solvent temperature-controlled to a temperature range of 60 ° C. or lower for a predetermined time, pulling it up, and leaving it in clean air to dry. A method for washing and drying a carrier box. 11. The method for cleaning and drying a carrier box according to claim 10, wherein the drying step is performed by the carrier box drying apparatus according to any one of claims 1 to 7. 12. The method according to claim 8, wherein the organic solvent is isopropyl alcohol.
Cleaning method of carrier box described in section