JPS61249583A - Shaking washing method - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

Detailed Description of the Invention (Industrial Application Field) The present invention relates to photomask blanks, photomasks,
The present invention relates to a method for cleaning objects to be cleaned, such as semiconductor wafers, various lenses, and jigs for holding these objects, and particularly to a shaking cleaning method for precisely cleaning objects to be cleaned.

(Prior Art) Conventionally, as an example of a method of cleaning the object to be cleaned, there has been a method of cleaning by stirring.

The first method of this stirring cleaning method is to first immerse the object to be cleaned in a cleaning liquid in a cleaning tank, and then rotate a stirring shaft attached to the cleaning tank that has blades, blades, etc. However, there has been a method of cleaning objects to be cleaned using the turbulent flow effect produced by imparting a flow rate to the cleaning liquid. The second agitation cleaning method uses clean air sent out by an air compressor installed outside the cleaning tank to an aeration pipe installed at the bottom of the cleaning tank (this aeration pipe has air coming out of it). A bubbling method is a method in which the cleaning liquid is fed into the cleaning liquid stored in the cleaning tank through a small hole (a small hole is provided), and the air bubbles give the cleaning liquid a flow velocity, and the object to be cleaned is cleaned by a turbulent flow effect. There was a way to clean it.

(Problems to be Solved by the Invention) However, in the conventional agitation cleaning method, it is difficult to clean the detailed surfaces of objects to be cleaned that have complex structures or surfaces with fine irregularities. It is difficult to provide turbulent flow and has the disadvantage that precision cleaning is not possible. In addition, in order to improve the cleaning effect in this stirring cleaning method, firstly, in the stirring cleaning method using a stirring shaft, in order to generate a complex turbulent flow effect, it is necessary to install turbulent flow such as various baffles on the stirring shaft. It is necessary to attach a turbulence generating member, and the shape and mounting position of this turbulence generating member have to be changed depending on the object to be cleaned. Furthermore, even in the agitation cleaning method using the bubbling method, it is necessary to provide the small hole of the aeration pipe at a position suitable for the size and shape of the object to be cleaned.
Another disadvantage is that the object to be cleaned must be placed in a manner appropriate to its location.

The present invention has been made in view of the above-mentioned circumstances, and its first purpose is to provide a cleaning method that can precisely clean the details of objects having various shapes and sizes. , the second purpose is to remove both hydrophilic dirt and lipophilic dirt adhering to the object to be cleaned, and the third purpose is to wash the object to be cleaned with a cleaning liquid, and to remove this cleaning liquid. It is an object of the present invention to provide a cleaning method for completely removing the cleaning liquid adhering to an object to be cleaned after discharging the cleaning liquid.

[Means for solving problems]

In order to achieve the above object, a first invention is to house an object to be cleaned and a cleaning means having a cleaning liquid in a cleaning tank, and to shake the cleaning tank to wash the object to be cleaned. In the second invention, an object to be cleaned and a cleaning means having a first cleaning liquid are housed in a cleaning tank, the cleaning tank is shaken to wash the object to be cleaned, and then the first cleaning liquid is applied. Then, a second cleaning liquid that dissolves the first cleaning liquid is injected into the cleaning tank, and the cleaning tank is shaken again to clean the object to be cleaned.

Further, in order to remove both hydrophilic stains and lipophilic stains, an aspect of the present invention is such that the cleaning liquid or the first cleaning liquid contains a hydrophilic cleaning liquid and a lipophilic cleaning liquid as main components, and The lipophilic cleaning liquid and the lipophilic cleaning liquid form an emulsion.

[For production]

In the present invention, by shaking the cleaning tank containing the object to be cleaned and the cleaning liquid, the cleaning liquid is shaken, and the cleaning liquid can be brought into rapid contact with the surface of the object to be cleaned, even in the smallest details. Therefore, dirt adhering to the surface of the object to be cleaned is reliably removed.

〔Example〕

This example will be explained in detail based on FIGS. 1 and 2. Note that FIG. 1 is a schematic cross-sectional view showing a cleaning tank containing an object to be cleaned and a cleaning liquid, and FIG. 2 is an assembled view of essential parts showing a shaker for shaking this cleaning tank.

First, the cleaning tank 1 (inner volume: 2600cc) of this example is:
It consists of an upper cleaning tank 2 and a lower cleaning tank 3, and has a capsule shape. And cleaning the top? 62 and lower cleaning tank 3
Each of the objects to be cleaned 4 (for example, 5 inches (vertical)
There are two holding parts 5 and 6 that have insertion parts for inserting and holding a photomask (photomask with a pattern made of chrome film on a glass substrate of 5 inches (horizontal) x 0.09 inches (thickness)). , and is attached by means of attachment means (not shown) such as screws. Further, an injection lower for injecting cleaning liquid is provided in a portion of the upper cleaning tank 2 having an arcuate cross section, and an injection valve 8 is attached to this injection lower. On the other hand, the section of the lower cleaning tank 3 has an arcuate cross section.
A discharge port 9 for discharging the cleaning liquid is provided, and a discharge valve 10 is attached to the discharge port 9.

Further, at the open ends of the upper cleaning tank 2 and the lower cleaning tank 3, the upper cleaning tank 2 and the lower cleaning tank 3 are each connected to a gasket 11 (this gasket is a convex portion 1 of the lower cleaning tank 3, which will be described later).
3 is stuck on top. ) and a protrusion 12.13 for attachment to the shaker described below. The convex portions 12 and 13 are respectively formed in the upper cleaning tank 2. It is provided along the periphery of the open end of the lower cleaning tank 3. Further, several (for example, three) holes (not shown) are provided in this convex portion 12.13 for positioning. Note that the convex portion 1 of the lower cleaning tank 3 is also attached to the packing 11.
A hole is provided at the same position as the hole provided in 3.

Next, the lower cleaning tank 3 is placed on a holding table (not shown), and then the two opposing corners of the object to be cleaned 4 are inserted into the holding part 6 to hold the object to be cleaned, Next, the upper cleaning tank 2 suspended above the lower cleaning tank 3 is gradually lowered so that the hole provided in the convex part 12 and the hole provided in the convex part 13 are aligned, and the bolt is inserted into this tank. Through the hole, the upper cleaning tank 2 and the lower cleaning tank 3 are integrally connected together with a nut. Then, the remaining two corners of the object to be cleaned 6 are attached to the holding part 5 of the upper cleaning tank 2.
is inserted and retained.

Next, a method of cleaning the object 4 to be cleaned using this cleaning tank 1 will be explained.

First, the cleaning tank 1 is attached to the ring-shaped cleaning tank fixing body 15 of the shaker 14. That is, the cleaning tank fixing body 1
The protrusions 12 and 13 are inserted into the circular gap 16 provided approximately in the center of the cleaning tank fixing body 15.
holes 18A, 18B provided in a pair of rectangular fixing body deforming parts 17A, 17B protruding from the cleaning tank fixing body 15 for holding the cleaning tank 1 by deforming the cleaning tank 1 inward; A hole 2 of a fixing body holder 20 that is inserted between the parts 17A and 17B and holds the cleaning tank fixing body 15.
1, and then tighten the fixed body deformable parts 17A, 17B and the fixed body holder 20 with the bolts 22 and nuts 23. Then, the cleaning tank 1 is held between the cleaning tank fixing bodies 15.

Next, the injection valve 8 provided at the top of the cleaning device 11 is opened, and approximately 1560 cc of fluorocarbon 25 (specific gravity: approximately 1.57), a lipophilic cleaning liquid for removing lipophilic stains, is poured into the cleaning solution.
inject. Next, about 780 cc of water 26, which is a hydrophilic cleaning liquid for removing hydrophilic dirt, is injected from the injection valve 8.

At any given time, the fluorocarbon 25 and the water 26 are separated from each other at an interface 27, and since the water 26 has a lower specific gravity than the fluorocarbon 25, it is located above the fluorocarbon 25.

Next, when the injection valve 8 is closed after injecting the water 26, approximately 260 cc of air 28 is present in the cleaning tank 1 (first
See diagram. ).

Next, the rotary plate 29 of the motor of the shaker 14 shown in FIG.
When rotated in the direction of arrow 30, the other rotary plate 32 connected by belt 31 rotates in the direction of arrow 33.

Next, when this rotary plate 32 rotates, one end is movably connected to the other rotary plate 32, and the other end is connected to the fixed body holder 20 through the vertical movement forcing slit 34.
An arm 35 connected to moves up and down. Then, the fixing body holder 20 also moves up and down as shown by the arrow 36, and the cleaning tank 1 held by the cleaning tank fixing body 15 also moves up and down (in the direction of the arrow 37 in FIG. 1).
, shake. In this example, this shaking was performed for about 3 minutes (45 times/min).

As mentioned above, when the cleaning tank 1 is shaken, the fluorocarbons 25, water 26, and air 28 existing inside it mix, and as a result, at least a portion of the fluorocarbons 25 and water 26 become an emulsion, and this emulsion and , the object to be cleaned 4 due to the synergistic effect with the liquid material of Freon 25 or water 26.
Clean details and surfaces.

That is, lipophilic stains are dissolved by the flon 25, while hydrophilic stains are dissolved by the water 26 and removed. Furthermore, since the emulsion consisting of Freon 25 and water 26 is also shaken, there is an increased chance of contact with either lipophilic or hydrophilic dirt, further enhancing the cleaning effect. In addition, if the dirt attached to the object 4 to be cleaned is neither oleophilic nor hydrophilic, the removal effect increases as the mixed air 28 bubbles collide with the foreign material, and the dirt is further removed from the surface. removed. Furthermore, since the emulsion collides with foreign matter, the peeling effect is further increased.

Next, the shaking is stopped, the injection valve 8 is opened to lower the internal pressure of the cleaning tank 1, and then the discharge valve 10 is opened to discharge the cleaning liquid consisting of the Freon 25 and water 26. At this time, if the emulsion is allowed to stand for about 1 minute after the stop, the emulsion will separate into Freon 25 and water 26, making it easier to discharge.

Next, close the discharge valve 10 and remove the fluorocarbon 2 in the same manner as described above.
5 and water 26 are injected and shaken again to wash the object 4 to be cleaned. After this shaking, the cleaning liquid is discharged in the same manner as described above, the discharge valve 10 is closed, about 2340 cc of isopropanol is injected, and the solution is shaken for about 3 minutes (45 times/min). This is because even after the Freon 25 and water 26 containing lipophilic and hydrophilic dirt are discharged, these cleaning liquids still adhere to the surface of the object to be cleaned. To increase cleanliness, both washes were washed with shaking with isopropanol to dissolve.

Further, since cleaning with this isopropanol is also performed in the same cleaning tank 1, it is possible to prevent foreign matter from re-adhering due to uneven drying caused by transfer of the object 4 to be cleaned between cleaning tanks.

Next, the object 4 to be cleaned is taken out from the cleaning tank 1 by the reverse procedure of the above-described storage means for the object 4 to be cleaned and dried.

As described above, according to this example, it is possible to simultaneously remove not only hydrophilic and lipophilic stains, but also foreign substances such as dust attached to the surface of the object to be cleaned, and the shaking action rapidly removes hydrophilic and lipophilic stains. dirt can be removed. In addition, since a hydrophilic cleaning liquid that creates an emulsion and a lipophilic cleaning liquid are used, the synergistic effect of the emulsion and the liquid cleaning liquid further improves the cleanliness. Furthermore, in this example, since the holding part 5 is removable, it can also be used for cleaning photomasks of other sizes by attaching a holding part suitable for holding photomasks of other sizes. is possible,
A similar effect can be achieved.

In the above embodiments, a gas consisting of air was also accommodated in the cleaning tank, but this may be used. It is better to accommodate the

In addition, in the above embodiment, a holder suitable for attaching a photomask as an object to be cleaned was provided, but if a holder suitable for attaching a photomask as an object to be cleaned, such as another lens, is provided in the cleaning tank, various types of The object to be cleaned can be similarly cleaned without changing the cleaning means. Moreover, although Freon and water were used as the lipophilic cleaning liquid and the hydrophilic cleaning liquid, respectively, other substances may be used. That is, any material that creates an emulsion may be used. Further, in order to facilitate the creation of an emulsion, an emulsifier may be included to an extent that does not affect cleaning (however, 0 is also included). Although isopropanol was used as the cleaning liquid for dissolving the lipophilic cleaning liquid and the hydrophilic cleaning liquid, it may be determined as appropriate depending on the lipophilicity and the hydrophilic cleaning liquid.

〔Effect of the invention〕

As described above, the present invention has a very high cleaning effect, and also removes lipophilic and hydrophilic stains at the same time. With this method, cleaning can be performed without changing the cleaning means such as the structure of the stirring shaft.

[Brief explanation of the drawing]

FIG. 1 is a schematic cross-sectional view of a cleaning tank according to an embodiment of the present invention, and FIG. 2 is an assembled view of essential parts of one of the embodiments. DESCRIPTION OF SYMBOLS 1...Cleaning tank, 2...Upper cleaning tank, 3...Lower cleaning tank, 4...Object to be cleaned, 5, 6...Holding part, 12.
13... Convex part, 14... Shaker, 15... Cleaning tank fixing body, 16... Gap part, 17A, 17B... Fixing body deformation part, 20... Fixing body holder, 25... Freon (lipophilic cleaning liquid), 26... Water (hydrophilic cleaning liquid),
27... Interface, 28... Air Figure 1

Claims (8)

[Claims] (1) A shaking cleaning method characterized in that an object to be cleaned and a cleaning means having a cleaning liquid are housed in a cleaning tank, and the object to be cleaned is washed by shaking the cleaning tank. (2) The shaking cleaning method according to claim (1), wherein the cleaning means comprises a cleaning liquid. (3) The shaking cleaning method according to claim (1), wherein the cleaning means comprises a cleaning liquid and gas. (4) The cleaning liquid contains a hydrophilic cleaning liquid and a lipophilic cleaning liquid as main components, and the hydrophilic cleaning liquid and the lipophilic cleaning liquid form an emulsion. Range items (1) and (2)
The shaking cleaning method described in Section 1 or Section (3). (5) Place an object to be cleaned and a cleaning means having a first cleaning liquid in a cleaning tank, shake the cleaning tank to wash the object to be cleaned, then discharge the first cleaning liquid, and then A shaking cleaning method comprising: injecting a second cleaning liquid that dissolves the first cleaning liquid into the cleaning tank, and shaking the cleaning tank again to clean the object to be cleaned. (6) The shaking cleaning method according to claim (5), wherein the cleaning means comprises a first cleaning liquid. (7) The shaking cleaning method according to claim (5), wherein the cleaning means comprises a first cleaning liquid and gas. (8) A patent characterized in that the first cleaning liquid contains a hydrophilic cleaning liquid and a lipophilic cleaning liquid as main components, and the hydrophilic cleaning liquid and the lipophilic cleaning liquid form an emulsion. Claims paragraphs (5) and (
The shaking cleaning method described in item 6) or item (7).