JPH11214364A - Semiconductor wafer processing apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable fine particle to be efficiently removed by charging the fine particles positively to generate line of electric force and forming ion stream. SOLUTION: A cathode 21 and an anode 22 are applied with predetermined voltage through a power supply line 42 from a power supply 41, respectively. As a result, etching gas from a reaction chamber 12 is negatively charged with the cathode 21 positioned near the reaction chamber 12. By radiation of ultraviolet light in a load-lock chamber 11 by an ultraviolet light source 23, ionization of the fine particles is further accelerated. The negatively charged fine particles are directly electrically drawn to the direction of the anode 22 along the line of electric force 31 formed with the cathode 21 and the anode 22 by Coulomb force, and efficiently exhausted from a vacuum outlet 14 through a vacuum pump outside the load-lock chamber 11. Thereby, contamination hardly occurs in the load-lock chamber 11.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a technique for removing fine particles by utilizing electric discharge in a semiconductor wafer processing apparatus.

[0002]

2. Description of the Related Art FIG. 5 is a schematic structural view of a conventional semiconductor wafer processing apparatus as viewed in plan.

This semiconductor wafer processing apparatus includes a pair of processing chambers for performing various processes such as etching a semiconductor wafer.
(Here, a reaction chamber) 12, a load lock chamber 11 which is a preliminary exhaust chamber connected to the reaction chambers 12, and a semiconductor wafer transfer system 13 and a pair of vacuum exhaust ports 14 are provided in the load lock chamber 11. Is provided. Reference numeral 15 denotes a pair of arms for mounting the semiconductor wafer, which constitute the transfer system 13.

When various processes such as etching are performed on a semiconductor wafer, fine particles are generated from the reaction chamber 12. That is, in the reaction chamber 12, fine particles are generated by the process gas or the reaction product, and flow into the load lock chamber 11 from the reaction chamber 12 side when transferring the wafer, thereby causing dust.

In the conventional particle removing apparatus, for example, the gas is evacuated from the vacuum exhaust port 14 provided in the load lock chamber 11 and the particles generated in the reaction chamber 12 are simultaneously exhausted.

[0006]

However, in the above configuration, since the load lock chamber 11 is merely evacuated, the removal of fine particles (particles) causing dust is insufficient.

[0007]

In order to solve the above-mentioned problems, the present invention solves the above-mentioned problems by positively charging the fine particles, thereby generating lines of electric force to form a flow of ions, thereby reducing the fine particles. It is designed to remove it efficiently.

That is, according to the first aspect of the present invention, in a semiconductor wafer processing apparatus provided with a vacuum chamber and having a vacuum exhaust port in the vacuum chamber, an electrode for charging gas or fine particles is provided in the vacuum chamber. It is characterized by being installed.

According to the second aspect of the present invention, in the configuration of the first aspect, an ultraviolet light source for charging gas or fine particles inside the vacuum chamber is installed in the vacuum chamber.

According to a third aspect of the present invention, in the configuration of the first or second aspect, the vacuum chamber comprises a semiconductor wafer processing chamber and a load lock chamber connected to the processing chamber. A cathode is disposed on the processing chamber side of the lock chamber, and an anode is disposed on the vacuum exhaust port side.

According to a fourth aspect of the present invention, in the configuration of the third aspect, a filter for capturing fine particles is provided near the anode.

[0012]

FIG. 1 is a schematic structural view of a semiconductor wafer processing apparatus according to an embodiment of the present invention as viewed in plan, and FIG. 2 is a schematic structural view of the same apparatus as viewed from the side.

In FIG. 1, reference numeral 11 denotes a load lock chamber, 1
2 is a pair of reaction chambers, 13 is a semiconductor wafer transfer system, 14
Is a vacuum exhaust port, and 15 is a pair of arms for mounting a semiconductor wafer constituting the transfer system 13. These structures are shown in FIG.
Is the same as the prior art device shown in FIG.

In this embodiment, a cathode 21 and an anode 22, which are electrodes for charging gas or fine particles, and an ultraviolet light source 23 are installed in the load lock chamber 11.

That is, as shown in FIG. 2, a cathode 21 is arranged on each reaction chamber 12 side of the load lock chamber 11 and an anode 22 is arranged on each vacuum exhaust port 14 side. A power supply 41 is connected via a power supply line 42, and the cathode 21 is connected from the power supply 41 through a power supply line 42.
A predetermined voltage is applied to the anode 22 and the anode 22, respectively.

The ultraviolet light source 23 is connected to the load lock chamber 1.
1 is arranged outside, and the inside of the load lock chamber 11 is irradiated with ultraviolet light through a window 25 made of glass or acrylic resin.

When an etching process is performed in the reaction chamber 12, fine particles are generated in the reaction chamber 12 by a process gas or a reaction product, and flow into the load lock chamber 11 from the reaction chamber 12 when transferring a wafer. I do. For example, if the etching gas is chlorine, the load lock chamber 1
There is a possibility that chlorine accumulates in the first and the inside of the load lock chamber 11 is contaminated.

In this case, a predetermined voltage is applied to the cathode 21 and the anode 22 from the power supply 41 through the power supply line 42. Then, the etching gas exiting from the reaction chamber 12 is supplied to the cathode 21 provided near the reaction chamber 12.
To be negatively charged. At that time, by the ultraviolet light source 23,
When the inside of the load lock chamber 11 is irradiated with ultraviolet light, ionization of the fine particles is further promoted.

The negatively charged fine particles are immediately attracted by the Coulomb force to the anode 22 along the line of electric force 31 formed by the cathode 21 and the anode 22, and the vacuum pump ( (Not shown) to efficiently discharge the load lock chamber 11 to the outside.
Contamination in the load lock chamber 11 hardly occurs.

As described above, particles due to the etching gas and reaction products generated from the reaction chamber 12 side
(Particles) are not only evacuated, but also
By generating lines of electric force 31 by the anode 1 and the anode 22 to form a flow 32 of charged fine particles, the fine particles can be effectively removed.

As shown in FIG. 3, it is more preferable that a filter 61 is provided so as to cover the anode 22.

In this case, the fine particles are removed from the filter 61.
And the anode 22 is not stored, so that the anode 22 can be prevented from being excessively contaminated.

In the configuration shown in FIGS. 1 and 2,
Although the electrodes 21 and 22 are both disposed in the load lock chamber 11, the electrodes 21 and 22 may be disposed outside the load lock chamber 11 as shown in FIG. In that case, the shape of the cathode 21 and the anode 22 is a ring shape surrounding the load lock chamber 11.

Further, in this embodiment, the case where the load lock chamber 11 with transfer is used as the vacuum chamber has been described, but it goes without saying that the same effect can be obtained even with a local vacuum vessel.

[0025]

According to the semiconductor wafer processing apparatus of the present invention, the following effects can be obtained.

(1) After the fine particles that are present in the vacuum chamber and are the source of dust are negatively charged by the cathode, the charged fine particles are attracted by Coulomb force in the anode direction.
Since the flow of the fine particles can be formed, the lines of electric force can be generated in a wide range, and the fine particles in a vacuum can be efficiently discharged to the outside. As a result, the generation of dust can be significantly suppressed and a favorable vacuum state can be maintained.

(2) In particular, when the vacuum chamber is irradiated with ultraviolet light by an ultraviolet light source, ionization of the fine particles is further promoted, so that discharge of the fine particles is improved.

(3) If a filter is provided so as to cover the anode, it is possible to prevent fine particles from accumulating on the anode and becoming dirty.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram showing a planar view of a semiconductor wafer processing apparatus according to an embodiment of the present invention.

FIG. 2 is a schematic configuration diagram of the apparatus of FIG. 1 as viewed from the side.

FIG. 3 shows a filter installed around an anode.

FIG. 4 is a diagram in which a cathode and an anode are arranged outside a load lock chamber.

FIG. 5 is a schematic configuration diagram showing a planar view of a conventional semiconductor wafer processing apparatus.

[Explanation of symbols]

11: load lock chamber, 12: reaction chamber, 13: transport system,
14 vacuum exhaust port, 21 cathode, 22 anode, 23 ultraviolet light source, 61 filter

Claims (4)

[Claims] 1. A semiconductor wafer processing apparatus having a vacuum chamber and having a vacuum exhaust port opened in the vacuum chamber, wherein an electrode for charging gas or fine particles is installed in the vacuum chamber. Semiconductor wafer processing apparatus. 2. The semiconductor wafer processing apparatus according to claim 1, wherein an ultraviolet light source for charging gas or fine particles inside the vacuum chamber is provided in the vacuum chamber. 3. The vacuum chamber includes a semiconductor wafer processing chamber and a load lock chamber connected to the processing chamber. A cathode is provided on the load lock chamber on the processing chamber side and an anode is provided on the vacuum exhaust port side. The semiconductor wafer device according to claim 1 or 2, wherein each of the semiconductor wafer devices is arranged. 4. The semiconductor wafer processing apparatus according to claim 3, wherein a filter for capturing fine particles is provided near the anode.