JPH03139832A - Jet scrubber - Google Patents

Abstract

PURPOSE:To exhibit sufficient cleaning capability regardless of the type of contaminant by watertightly forming a structure for containing a wafer, a chuck and a nozzle, incorporating water inside it, and mounting the wafer, the chuck for hooding the wafer, and the exit of the nozzle for injecting high pressure water under the water level. CONSTITUTION:High pressure water to be injected from the exit O of a nozzle 1 is fed to the surface of a wafer 2 through the wafer W in a structure 7, and cavitation bubbles are generated by friction with static water W therebetween. The bubbles are ruptured when they reach the surface of the wafer 3 separated by a predetermined distance from the exit O of the nozzle 1 to generate a large impact pressure. Various contaminants on the wafer are removed by the impact pressure. In this case, in order to easily generate the bubbles, the water W is degassed, or the water is heated. Thus, the structure 7 is formed with a cover 14 in a sealing construction, the inside is evacuated, or a heater 26 is installed therein.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a jet scrubber that cleans a substrate or wafer with a jet of water.

[Prior Art] Such a conventional jet scrubber is shown in FIG. In Figure 2, the substrate (wafer) that is the object to be cleaned
2 is held on the chuck 3 by vacuum action or the like.

This chuck 3 is rotated by a DC motor 5 at an appropriate rotational speed, and can be moved up and down by a vertical movement mechanism 6 for each chuck.

The nozzle 1 releases the wafer 2 by the high-pressure water jet ejected from the nozzle 1.
This high-pressure water is used to clean the upper surface, and is supplied to the nozzle 1 from a pipe 9. Reference numeral 4 indicates a swinging mechanism for swinging the nozzle, and the swinging mechanism allows the high-pressure water jet ejected from the nozzle to evenly impinge on the entire surface of the wafer. After colliding with the surface of the wafer 2, the jet stream passes through the pipe 8 and is discharged downstream (indicated by reference numeral 10). Note that the various devices described above are housed within the structure 7.

[Problems to be Solved by the Invention] As described above, in the conventional jet scrubber, a high-pressure jet water stream (high-pressure water jet) is ejected from the nozzle 1 onto the surface of the wafer 2, and the impact force of this jet stream causes the wafer to be However, depending on the type of contamination, a sufficient cleaning effect may not be obtained.

The present invention was proposed in view of the problems of the prior art as described above, and the purpose of the present invention is to provide a jet scrubber that can exhibit sufficient cleaning performance regardless of the type of contamination. It is said that

[Means for Solving the Problem] Generally, it is well known that when a high-pressure jet is applied to the surface of an object underwater, erosion occurs in the portion of the surface that is hit by the jet due to cavitation bubbles. The present invention attempts to utilize this erosion effect for cleaning.

The jet scrubber of the present invention is a jet scrubber that cleans the surface of the wafer by holding a wafer on a chuck, rotating the chuck, and jetting high-pressure water onto the wafer from a nozzle. The structure for accommodating the wafer is configured to be watertight and contains water therein, and the wafer, the chuck that holds it, and the outlet of the nozzle that sprays high-pressure water are installed below the water surface.

In carrying out the present invention, it is preferable to have means for moving the nozzle across the wafer surface.

Further, it is preferable that the structure is covered with a cover and the inside of the cover can be evacuated at any time by exhausting air from an exhaust port.

Furthermore, it is preferable to provide means for raising the temperature of the water contained inside the structure.

[Function] According to the present invention having the above-described configuration, the high-pressure water jetted from the nozzle passes through still water and reaches the wafer surface, but during this time friction occurs between the high-pressure water jet and the still water. Cavitation bubbles are generated. When the cavitation bubbles reach the wafer surface, they are destroyed and generate a large impact pressure, which removes dirt on the wafer surface.

Here, by covering the structure with a cover and evacuating from the exhaust port, the inside of the cover can be made into a vacuum at any time, or the temperature of the water built inside the structure can be changed. By providing a means to raise the
Furthermore, cavitation bubbles can be easily generated, and impact pressure can be generated by the destruction of the cavitation bubbles.

[Example 1] An example of the present invention will be described below with reference to FIG. Note that the same members as those of the prior art shown in FIG. 2 will be described with the same reference numerals.

In FIG. 1, a chuck 3 on which a wafer 2 is placed (held) is provided. Here, the chuck 3 holding the wafer 2 is rotated by a DC motor 5 through a shaft 27 passing through a watertight seal 24, and is moved up and down by a father vertical movement mechanism 6.

A structure 7 that houses the wafer 2, the chuck 3, the nozzle 1, etc. described below, is configured to be watertight, and contains water W therein. The wafer 2, the chuck 3, and the outlet 0 of the nozzle 1 for cleaning the wafer are installed below the water surface. A traverse mechanism 11 is connected to the nozzle 1 in order to move the nozzle 1 to the right or left on the center line on the surface of the wafer 2.

This transverse mechanism 11 is configured to move rightward and leftward by a screw 12 and a motor 13 that rotates it. However, this traverse mechanism is just an example;
It is possible to traverse the nozzle 1 using other means. For example, a swinging mechanism 4 as shown in FIG. 2 may be used.

High-pressure water supplied to the nozzle 1 is supplied from a tank 20, is increased in pressure by a pump 19, and is ejected from an outlet O of the nozzle 1 via a pipe 18 and a flexible hole 16.

The structure 7 that houses the wafer 2, chuck 3, nozzle 1, etc. is covered by a cover 14, so that the water surface 17
, the traversing mechanism 11, etc. are also covered with the cover 14, and this part has a sealed structure. Then, the space S covered by the cover 14 is evacuated to a vacuum state by a pump (not shown) through the exhaust port 21, and the water W inside the structure 7 can be degassed. Note that the release of atmospheric pressure after the completion of deaeration is performed by a mechanism (not shown) located downstream of the exhaust port 21.

In addition to the mechanism for evacuating the space S to create a vacuum state, in the embodiment shown in FIG.
It is also configured so that it can be raised by

This water is supplied through the water supply port 22 and drained through the drain port 23.

Next, the operation of the embodiment shown in FIG. 1 will be explained.

The high-pressure water ejected from the outlet O of the nozzle 1 passes through the water W inside the structure 7 and reaches the surface of the wafer 2, but during this time, cavitation bubbles are generated due to friction with the static water W. When the cavitation bubbles reach the surface of the wafer 2 at a certain distance from the outlet O of the nozzle 1, they are destroyed and generate a large impact pressure. This impact pressure removes various contaminants present on the wafer surface.

In order to facilitate the generation of cavitation bubbles at this time, the structure 7 is made into a sealed structure with the cover 14 and the inside thereof is kept in a vacuum state in order to deaerate the static water W and increase the water temperature as described above. , or by installing a heater 26.

After cleaning the wafer 2, the wafer is raised above the water surface 17 using each chuck 3, and then the chuck 3 is rotated at high speed to release the removed contaminants to the outside by centrifugal force. The cleaning cycle is completed by drying the surface.

[Effect of the invention] The effects of the jet scrubber of the present invention are listed below.

(1) Even types of contamination that cannot be removed with conventional jet scrubbers can be cleaned and removed.

(2) Cleaning performance is improved, and the yield of various semiconductor chips manufactured from cleaned wafers is improved.

(3) The manufacturing cost is low because it has a simple structure in which the wafer, check, and nozzle outlet are placed in water.

(4) By covering the structure housing the wafer, chuck, nozzle, etc. with a cover and exhausting air from the exhaust port,
By configuring the cover so that it can be evacuated at any time, or by providing a means for increasing the temperature of the water contained inside the structure, the amount of cavitation bubbles generated can be increased. A great cleaning effect can be obtained.

[Brief explanation of the drawing]

FIG. 1 is a sectional front view showing one embodiment of the present invention, and FIG. 2 is a sectional front view showing a conventional technique. 1... Nozzle 2... Wafer 3... Chuck 7... Structure 17... Water surface W... Water built inside the structure tm

Claims (1)

[Claims] In a jet scrubber that holds a wafer on a chuck, rotates the chuck, and sprays high-pressure water onto the wafer from a nozzle to clean the surface of the wafer, the structure housing the wafer, chuck, and nozzle is watertight. What is claimed is: 1. A jet scrubber, characterized in that the wafer, a chuck for holding the wafer, and a nozzle outlet for ejecting high-pressure water are installed below the water surface.