JPH01135025A - Drying device - Google Patents

Abstract

PURPOSE:To prevent generation of water marks and to reduce drying time by drying objects to be dried and a tool for holding them separately. CONSTITUTION:An organic solvent 6 which is stored at the bottom of a vapor tank 3 is heated by a heating device 8 to evaporate, thus generating vapor. Since vapor goes up through a tray 9 and is cold-trapped by a cooling pipe 5, the inside of the vapor tub 3 completely turns into a vapor environment. If a jig 11 which houses wafers 12 moves down to a specified position which is located under a holder 15, the holder 15 penetrates the jig 11 upward because the place shape is formed smaller than that of a bottom window hole 11a. Then, a group of wafers 12 which are held by a holding groove 11b of the jig 11 are transferred to a holding groove 15b of the holder 15 and are held thereby. Thus, the group of waters 12 and the jig 11 are separated within the vapor tub 3 and are vapor-dried separately.

Description

Detailed Description of the Invention [Industrial Application Field] The present invention relates to a drying technique, particularly a technique for drying a plurality of objects to be processed at once. Concerning what is effective for use in drying techniques.

[Conventional technology]

In the manufacturing of semiconductor devices, a device for drying wafers after washing with water is used to hold multiple wafers in a jig and immerse them in a vapor atmosphere of an organic solvent such as isopropyl alcohol, so that the temperature between the wafers and the vapor increases. There is a HEPA drying equipment that is configured to displace water and an organic solvent in vapor droplets by a difference, and then dry the wafer by evaporation of the organic solvent.

Incidentally, examples of vapor drying devices described include Japanese Patent Application Laid-Open No. 56-168072 and Japanese Utility Model Application No. 59-1382.
There is Publication No. 32.

[Problem that the invention seeks to solve]

In such vapor drying equipment, the jig that holds the wafer has a lower thermal conductivity and a larger heat capacity than the wafer, so the jig does not replace water with the organic solvent and evaporate the organic solvent. The drying process takes longer than the wafer, resulting in the formation of water marks where the wafer contacts the jig, and the drying cycle is determined by the drying of the jig. The present inventor has revealed that there is a problem that the drying time is prolonged.

SUMMARY OF THE INVENTION An object of the present invention is to provide a vapor drying device that can prevent the occurrence of water marks and shorten the drying time.

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]

An overview of typical inventions disclosed in this application is as follows.

That is, a plurality of objects to be processed and a jig for holding the objects are dried separately.

[Effect]

According to the above-mentioned means, the plurality of objects to be processed and the jig that holds them are dried separately, so even if the jigs have low thermal conductivity and large heat capacity, the objects to be processed will remain dry. You won't have to be affected.

As a result, the watermark phenomenon caused by contact with the jig and drying of the workpiece does not occur on the workpiece. Moreover, since the drying operation time can be made to substantially depend on the drying time of the object to be treated, the drying operation time is limited.

〔Example〕

FIG. 1 is a vertical cross-sectional view showing a vapor drying device as an embodiment of the present invention, and FIG. 2 is a vertical cross-sectional view for explaining its operation.

In this embodiment, this vapor drying apparatus is equipped with a main body 1 formed in a substantially box shape, and an upper part of the main body 1 is used for inserting and removing a processing object holding jig (hereinafter referred to as a "jig"). Entrance/exit 2 has been opened. Inside the main body 1, a vapor tank 3 as a drying chamber, which is formed of quartz glass and has a similar shape to the main body 1, is installed concentrically with a gap around the outer periphery. The opening 4 faces the entrance/exit 2 of the main body l.

A coiled cooling pipe 5 for circulating cooling water is attached to the inner peripheral wall of the opening 4 of the vapor tank 3.

Inside the vapor tank 3, an organic solvent 6 such as isopropyl alcohol (IPA), trichlene, or methanol alcohol is stored, and this is supplied from the outside of the main body l through a liquid supply pipe 7. . Below the vapor tank 3 is a heating value consisting of an infrared heater or a heat block with a sheathed heater embedded in an iron or aluminum block! f8 is installed, and it is added
The heating device 8 is configured to heat the organic solvent 6 to forcibly evaporate it to generate vapor.

Further, above the liquid level of the organic solvent 6 in the vapor tank 3, a tray 9 with an open top is installed so as to receive water droplets, and at the bottom of the tray 9 there is a main body l. A drain pipe 10 communicating with the outside is connected. The tray 9 has a multi-stage structure in which receiving trays having a central hole are arranged above and below, so that the organic solvent 6 can be
This allows the vapor that is saved to pass upward. Then, a jig ll is suspended and set directly above the tray 9, and a jig 1
The wafer 1 is made of a fluororesin having good chemical resistance and is configured to hold one or more wafers 12 as objects to be processed.

An infrared lamp heater 13, which serves as a heating means exclusively for the jig, is installed in the body of the main body, and is placed approximately at the center of the height.This heater 13 is set inside the vapor tank 3 through the quartz glass. The jig 11 is configured to be able to effectively heat the heated jig 11.

Further, on the tray 9 is a support 14 made of quartz glass or the like.
are arranged substantially vertically and fixedly erected, and this support column 14 is configured to be supported together with the tray 9 by a stand (not shown) installed in the vapor tank 3. The support 14 extends to a position above the hanging position of the jig 11, and a holder 15 is horizontally arranged and integrally fixed to the upper end of the support 14. The holder 15 is made of quartz glass or the like and is formed into a substantially rectangular parallelepiped in plan view, and the rectangle corresponds to the bottom window hole 1 in the jig 11.
It is set to have a similar shape that is slightly smaller than 1a. A holding surface 15a is provided on the upper surface of the holder 15 for holding the wafer 1.
The holding surface 15a has a plurality of holding grooves 15b.
are arranged in the axial direction at approximately equal intervals and carved in a circular arc shape. This holding groove 15b group is set to correspond to the holding groove a11b carved on the inner surface of the side wall of the jig 11.
Thereby, the holder 15 can receive and hold the group of wafers 12 held by the jig 11.

A drainage port 16 is provided at the bottom of the holding terminal 5b of the holder 15 so as to catch water droplets dripping onto the holder 15 and the support column 14. It is connected to the drain pipe 10 of the tray 9 through a drain path 17 opened inside the tray 9 .

Next, the effect will be explained.

The liquid organic solvent 6 stored at the bottom of the vapor tank 3 is heated by the heating device 28 to generate vapor.

The vapor passes through the tray 9 and rises, and is cold-trapped by the cooling pipe 5, so that the inside of the vapor tank 3 becomes completely vapor atmosphere.

As shown in FIG. 1, a jig 11 containing a plurality of wafers 12 (usually about 25 wafers) is suspended by a hash drake 18, and an opening 4 is opened into a vapor tank 3 serving as a drying chamber.
From there, it is lowered so that it is aligned with the holder 15.

As shown in FIG. 2, when the jig 11 is lowered to a predetermined position below the holder 15, the planar shape of the holder 15 is formed to be smaller than the bottom window hole 11a of the jig 11. When the holder 15 penetrates the jig 11 upward,
The groups of wafers 12, each held by the holding tMIlb of the jig 11, are transferred to the holding grooves 15b of the holder 15, and are respectively held. This results in
The group of wafers 12 and the jig 11 are separated in the vapor tank 3 and are vapor-dried separately.

In this embodiment, the jig 11 set at a predetermined position is heated by an infrared lamp heater 13 without contact. The temperature begins to rise (.

At the time of loading, the wafer 12 and the jig 11 have been washed with water in the previous process, so they are wet with water and at a low temperature.

The wafer 12 and the jig 11 are now in a low temperature state.
Is there a vapor atmosphere? +? ! When this occurs, vapor condenses and adheres to those surfaces. The condensed organic solvent gradually replaces the moisture moistening the surfaces of the wafer and the jig, and the replacement ends when the surface temperatures of the wafer 12 and the jig 11 become equal to the vapor temperature.
On the other hand, the water that has replaced the organic solvent flows down the surface together with foreign matter remaining on the surface, drips onto the bottom of the holding groove 15b of the holder 15 and onto the tray 9, and is collected by the drain port 16 and the tray 9. , is discharged to the outside through the drain path I7 and the drain pipe 10. In this way, by preventing water from getting mixed into the organic solvent 6 stored at the bottom of the vapor tank 3, it is possible to avoid the mixed water from re-evaporating into water vapor. Therefore, it is possible to prevent moisture from re-adhering to the wafer 12.

At the point when the replacement is completed, the jig 11 is activated by the handler 18.
It is pulled up from the vapor tank 3 by.

At this time, when the jig 11 is raised to a predetermined position above the holder 15, the holder 15 is relatively pulled out from the jig 11, so the wafer 12 on the holder 15
The group will be delivered to the jig 11.

When the jig 11 and the wafer 12 are pulled up from the vapor tank 3, the temperature of the jig 11 and the wafer 12 has increased due to the heating of the vapor atmosphere. The agent will vaporize while taking away heat. When the organic solvent is completely vaporized, the jig 11 and the wafer 12 are dried. The vaporized organic solvent is sucked by a ventilator (not shown) on the main body 1 and is prevented from diffusing elsewhere.

By the way, since the wafer is made of silicon, it has good thermal conductivity and has a thickness of 0.5 mm. Since it is approximately 5 mm, its heat capacity is extremely small.

On the other hand, since the jig is made of fluororesin, it has poor thermal conductivity and has a maximum wall thickness of about 10 mm, so it has a large heat capacity. In other words, the jig is less likely to heat up and cool down than the wafer. This means that in the jig, the effect of replacing moisture with the organic solvent and the effect of vaporizing the organic solvent are delayed compared to those in the wafer.

If moisture remains in the jig, there is a possibility that the moisture will be transferred to the wafer due to contact between the jig and the wafer.

Furthermore, if the #B solvent remains on the jig, the solvent will adhere to the wafer again and remain on the wafer.

In such cases, oxygen dissolves into the water droplets or solvent attached to the wafer, and this oxygen causes local oxidation of the wafer surface where the water droplets or solvent have been attached for a long time (so-called watermark). occurs.

Due to these circumstances, in the conventional case where vapor drying is performed while the wafer is held in a jig, water droplets or solvent remain in the contact area between the wafer and the jig, resulting in the formation of water marks. It will be done.

However, in this embodiment, the group of wafers 12 is
Since it is separated from the jig 11 and vapor-dried separately from the jig 11, water marks are prevented from being formed at the contact portion. That is, by drying the jig and the wafer separately, localized residual of water droplets and solvent is not caused.

Moreover, in this embodiment, the jig 11 is heated by the dedicated infrared lamp heater 13, and the temperature is forcibly raised in addition to the heating by the vapor atmosphere.
The drying speed is faster than that for the group of wafers 12, and as a result, the formation of watermarks can be more reliably prevented even when the jig 11 contacts the group of wafers 12 after they are received.

That is, the jig 11 is forcibly heated by the infrared lamp heater 13 to a constant temperature (approximately 82.4° C.) that is equal to the vapor atmosphere temperature when the wafer 12 is heated by the vapor and reaches a certain temperature (approximately 82.4° C.). Ru.

Since dew condensation occurs due to the difference between the temperature of the jig and wafer during the temperature rise and the vapor atmosphere temperature, the water and organic solvent are sufficiently replaced. At this time, even if the jig is forcibly heated, it has sufficient latent heat due to its large heat capacity, so that dew condensation is sufficiently prevented.

Incidentally, even if the infrared lamp heater 13 is turned on when the jig is turned on, thermal energy is wasted in the initial stage for preheating the support, etc., so the actual time to start heating the jig is after a predetermined period of time has elapsed after the jig is turned on. become. This heating delay is also a factor that ensures dew condensation.

In this way, the time required to raise the temperature of the jig 11 to a predetermined temperature is the same as that of the wafer 12, and as a result, the end of the replacement action of moisture and organic solvent is also the same, so that the wafer 12 is It can be set when a predetermined temperature is reached. In other words, the time required for one cycle of vapor drying of a wafer is significantly reduced.

In this embodiment, since heating is performed by the infrared lamp heater 13, the temperature of the jig 11 and the wafer 12 is increased more than when heating is performed only by vapor. In this way, the jig 11 and the wafer 12 are sufficiently heated, so when the organic solvent vaporizes after being pulled up, the organic solvent attached to them receives a sufficient amount of heat and vaporizes rapidly. It turns out. In other words, the heat of vaporization is quickly removed from the jig ll and the wafer 12, so
The temperature will drop at a steep slope.

In this way, the organic solvent adhering to the jig 11 is rapidly evaporated, so that after the jig 11 is lifted from the vapor tank 3, it can be left for a short time and then moved from the ventilator installation location.

In other words, one cycle time of drying work can be further shortened.

According to the embodiment described above, the following effects can be obtained.

+11 By drying the workpiece and the jig for holding it separately, drying marks can be prevented from forming at the contact area between the jig and the workpiece, which improves drying accuracy. can be increased.

(2) By disassembling the workpiece and the jig and drying them with vapor, it is possible to prevent water marks from remaining in the contact area between the jig and the workpiece and the solvent, and drying accuracy is achieved. It is possible to increase the drying time and shorten the drying time.

(3) By heating the jig with a dedicated heater and forcibly raising it to four temperatures, the jig can be forcibly heated to the same temperature by the time the wafer reaches a certain vapor temperature. , the replacement action of moisture and organic solvent can be completed in the jig at the same time as the wafer,
Therefore, the jig can be lifted out of the vapor tank in time for the replacement action to finish on the wafer.
Drying work time can be further shortened.

(4) By raising the temperature of the jig and wafer higher than the vapor temperature, the organic solvent can be rapidly vaporized, so the wafer drying cycle can be shortened.

(5) By using an infrared lamp heater as a dedicated heating means, it is possible to heat only the jig by passing through the vapor tank, and it is also possible to avoid contact of the heat source with the vapor tank. The jig can be heated effectively and safety can be maintained.

(6) By installing a tray in the vapor tank and a drain port in the holder to catch water droplets, it is possible to prevent water from dripping into the organic solvent liquid, and to prevent water in the liquid from dripping. This can prevent re-evaporation and re-adhesion to the wafer.

(7) By configuring the tray in a multi-stage structure, it is possible to allow vapor to pass through, and therefore it is possible to suppress a decrease in the displacement effect between vapor and water.

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. Nor.

The drying means is not limited to the vapor drying method, but may also be a hot air drying method, a heating drying method, or the like.

A dedicated heating means for heating the tray and jig for receiving the water droplets may be omitted.

The dedicated heating means for heating the jig is not limited to an infrared lamp heater, but may also be a high frequency heating means or the like.

The above explanation has mainly been about the application of the invention made by the present inventor to wafer vapor drying technology, which is the field of application that formed the background of the invention, but is not limited thereto, and is applicable to photomasks, optical lenses, etc. It can be applied to all drying techniques. In particular, the present invention can be used to dry a plurality of plate-like objects at the same time to obtain excellent effects.

[Results of invention]

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

By drying the object to be processed and the jig for holding it separately, it is possible to prevent drying residue marks from occurring in the areas of the object to be processed that come into contact with the destroyed object. , drying accuracy can be increased.

[Brief explanation of the drawing]

FIG. 1 is a vertical cross-sectional view showing a vapor drying device as an embodiment of the present invention, and FIG. 2 is a vertical cross-sectional view for explaining its operation. 1... Main body, 2... Entrance/exit, 3... Vapor tank (drying room), 4... Opening, 5... Cooling pipe, 6...
- #Bf4 agent, 7...liquid supply pipe, 8...heating device,
9... Tray, 10... Drain pipe, 11... Jig,
12... Wafer (workpiece), 13... Infrared lamp heater (heating means dedicated to jig), 14... Support column, 15
...Holder, 16...Drainage port, 17...Drainage path,
18...Handler. Figure 2 1r 11...Mostly Table 1? ...to the crab (coffin room tL size) 1 do... support i 15... water le 7 pa 16... 瀞tLυ ・17...-! IrB 21t'I [)

Claims (1)

[Scope of Claims] 1. A drying apparatus characterized in that it is configured to dry a plurality of objects to be processed and a jig for holding the group of objects to be processed separately. 2. The drying apparatus according to claim 1, comprising a drying chamber for drying, and a holder for collectively receiving and holding a plurality of objects to be processed from a jig in the drying chamber. . 3. The drying device according to claim 2, wherein the drying chamber is constituted by a vapor tank that performs vapor drying. 4. The drying device according to claim 2, wherein the holder is installed vertically in the vapor tank so as to pass through the jig. 5. Claims characterized in that the jig is configured such that after the group of objects to be processed is delivered to the holder, the group of objects to be processed is vapor-dried at a position other than the group of objects in the vapor tank. The drying device according to item 2. 6. The drying apparatus according to claim 2, wherein the jig is configured to be heated by heating means.