JPS6396925A - Apparatus for cleaning wafer - Google Patents

Abstract

PURPOSE:To efficiently remove a dust particle which is deposited on the surface of an Si wafer by a method wherein, while the flow of a gas is being fed to the wafer on a wafer stage, the wafer is vibrated via a vibrating plate. CONSTITUTION:While a wafer such as an Si water or the like is put on a wafer stage 1, it is fixed, in a detachable manner, on the stage 1 through a vacuum chuck 4 which is connected to a vacuum pump. A jet-nozzle type opening 7 which is connected to a supply source 5 of a pressurizing gas is formed on the side of the stage 1, and the flow of the gas generated in front of the opening is fed to the surface of the wafer 2. In addition, the stage is connected to an ultrasonic generator 8 via a horn 9, and a vibrating plate which is vibrated by the output of the generator 8 is installed so that the wafer 2 can be vibrated in a prescribed way via the vibrating plate. Through this constitution, a dust particle which is deposited on the surface of the wafer can be removed with high efficiency by the flow of the gas and the vibration.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to an apparatus for performing a cleaning process on a silicon wafer or other wafer, that is, a cleaning process for removing dust particles adhering to the surface thereof.

(Prior Art) Conventionally, silicon wafers and other wafers are subjected to vacuum processing or other processing in a vacuum processing tank or in a vacuum processing tank.
There is known a type in which a wafer stage is provided on a conveyance path or other appropriate location connected to the wafer stage, on which the wafer is placed and can be fixed freely via a vacuum chuck or the like.

However, in this case, the means for cleaning the wafer, that is, the treatment for removing dust particles adhering to its surface, is generally to clean the wafer with water, and in such a case, the following method is used: accompanied by such inconvenience.

(Problems to be Solved by the Invention) That is, according to such means, the wafer must be removed from the stage each time, which is troublesome, and even after the cleaning, some dust particles remain. However, the remaining particles tend to become more firmly attached to the surface due to moisture entering the gap between the particles and the surface, which is a disadvantage.

(Means for Solving the Problems) The present invention aims to provide an apparatus free from such inconveniences, and it is an object of the present invention to provide a wafer stage in a vacuum processing tank, a conveyance path connected thereto, or any other suitable location. A silicon wafer or other wafer can be placed on this stage and fixed via a vacuum chuck or the like, and the stage is connected to a near blower or other pressure gas supply source via an air supply passage on the side of the stage. A jet nozzle or other opening is provided to cause the gas flow generated in front of the jet nozzle to act on the surface of the wafer, and the stage is configured as a diaphragm connected to an ultrasonic generator via a horn. Vibration is applied to the wafer via the diaphragm.

(Function) Thus, a gas flow acts on the surface of the wafer, and the dust particles adhering to the surface are removed along with the gas flow, and at this time, the wafer is subjected to vibrations. Vibration is applied through the plate, and the vibration has the effect of exfoliating the particles from the surface and also acts to disturb the boundary layer of the gas flow that tends to occur on the surface, thus Particles can be removed even better.

(Example) Embodiments of the present invention will be described with reference to the attached drawings.

Figure 1 shows one example. (1) shows a wafer stage prepared at an appropriate location such as on the upstream or downstream side of the vacuum processing tank, on the transfer line, or inside a clean bench. Another wafer (2) is placed on the stage (1) and placed on the stage (1) via a vacuum chuck (4) connected to a vacuum pump (not shown) via a communication path (3). It is fixed so that it can be attached and detached.

A jet nozzle-type opening (D) is provided on the side of the stage (1), which is connected to a near blower, N2 tank, or other pressure gas supply source (5) via an air supply passage (6), and a jet nozzle opening (D) is provided in front of the stage (1). The gas flow was made to act on the surface of the Eva (2), so that dust particles preliminarily deposited on the surface were removed along with the gas flow. In other words, the wafer (→) can be given the cleaning action of a so-called air processor.

In this case, the gas flow becomes a steady flow along the surface of the wafer (2), creating a boundary layer near the surface, which is sometimes several tens of microns thick, and the problem is
It is conceivable that it does not necessarily act effectively on particles smaller than microns.

According to the present invention, in view of this point, the stage (1) is equipped with a horn (9) attached to the ultrasonic generator (8) provided below the stage (1).
is connected to the wafer (8) to form a diaphragm that vibrates according to the output of the generator (8), so that a predetermined vibration is applied via the diaphragm to the wafer (8). The vibrations tended to cause the particles on the surface to detach therefrom and to disturb the boundary layer described above, thus allowing better removal of the particles.

Figures 2 and 3 show another example; in this case,
The wafer stage (1) is provided in a vacuum processing layer (10) on the outer periphery together with the generator (8) below it, and the processing tank (IG is configured to be freely evacuated by communicating with a vacuum pump 0). Furthermore, the above-mentioned opening (D is the tank (1)
An exhaust passage (121) is provided on one side wall of the interior of 0, and an exhaust passage (121) is opened in the other side wall opposite to this.In this case, the supply source (5) consists of an air blower, and an A filter (5a) is provided.

The remaining points are not particularly different from the previous ones.

Thus, the wafer (2) is subjected to the gas flow through the opening (n) and is also subjected to vibration through the diaphragm to remove dust particles adhering to its surface. This point is not particularly different from the previous embodiment, but
According to this embodiment, the gas flow also acts on the side walls on each side within the layer aG, and acts to remove dust particles that have previously adhered thereto. In this case, in order to further improve the removal of the particles on the side wall, an ultrasonic generator (13) is also provided on the outside of the outer wall so that the output of the generator a3 gives vibration to it. is also possible.

FIG. 4 shows a modification example, in which the air supply passage (6) and the exhaust passage 0b are connected to each other to form a circulation passage as a whole, and N2 gas or other gas is The gas cylinder (5b) was connected in order to introduce the gas, but the remaining points are not particularly different from the previous one.

(Effects of the Invention) According to the present invention, when a wafer is placed on a wafer stage and fixed, a gas flow is applied to the surface of the wafer to remove dust particles that have previously adhered to the surface. This eliminates the above-mentioned disadvantages of the conventional method in which the wafer is removed from the stage each time and washed with water, and furthermore, the wafer stage is mounted on a diaphragm connected to the output side of the ultrasonic generator. The vibration is applied to the wafer, which has the effect of making the removal of the particles even better and more efficient.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram of one example of the device of the present invention, and FIG. 2 is an explanatory diagram of another example.
An explanatory diagram of an example, FIG. 3 is an enlarged view of the main part thereof, and FIG. 4 is an explanatory diagram of a modification thereof. (1)...Wafer stage (ri...Wafer (4)
) Vacuum chuck (5)...Pressure gas supply WA
(6)...Air supply passage (7)...Opening (8)...
・Ultrasonic generator (9)...Horn Figure 1 Figure 2 Figure 3

Claims (1)

[Claims] A wafer stage is provided in a vacuum processing tank, or on a conveyance path connected thereto, or at any other suitable location, on which silicon wafers or other wafers can be placed and fixed via a vacuum chuck or the like; A jet nozzle or other opening connected to an air blower or other pressure gas supply source via an air supply passage is provided on the side of the wafer so that the gas flow generated in front thereof acts on the surface of the wafer, and A wafer cleaning processing apparatus comprising: a diaphragm connected to an ultrasonic generator via a horn;