JPH06123693A - Capturing inspection method and device therefor - Google Patents

Abstract

PURPOSE:To avoid contamination of clean air and reduction of yield for manufacturing a semiconductor device, and lowering of its characteristics, etc., by inspecting the capturing efficiency of a fine particle-capturing body by using a fine particle with a substance having sublimation property. CONSTITUTION:First and second switching valves 19 and 20 are opened, a particle which is liberated from a plasma generation part 12 is supplied to a passage, and, at the same time, a low-temperature air is injected halfway to a chamber 14, thus enabling particles to be flocculated at the merging part of the low-temperature air. A third switching valve 21 is in blocked state at that time. In this state, air including fine particles is fed to a capturing body 13 to capture particles to be inspected which is laid out inside the chamber 14. The number of particles in air passing through the capturing body 13 is counted by a particle counter 22.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fine particle collector having a function of collecting fine particles floating in the atmosphere, and particularly to a fine particle collecting efficiency of a filter such as a clean bench used in a semiconductor device manufacturing process. The present invention relates to a collection inspection method and a collection inspection device suitable for use in inspection.

[0002]

2. Description of the Related Art In recent years, miniaturization and high integration of semiconductor integrated circuits have been increasingly accelerated, and the manufacturing process thereof is also required to meet the miniaturization.

Therefore, as a method for inspecting the collection efficiency of fine particles, so-called particles, which greatly hinders the yield of semiconductor manufacturing, for example, di-2-ethylhexyl phthalate (hereinafter referred to as DOP), which has a property of condensing in the atmosphere, is used. A method using such a high boiling point organic solvent is currently used.

As shown in FIG. 2, this is because a DOP source 3 heats D to a supply passage 4 communicating with a chamber 2 in which a filter 1 as an inspected fine particle collector is placed.
OP is supplied, and low-temperature air from the low-temperature air source 5 is supplied on the way of the supply passage 4, whereby the DOP is once cooled, and is nuclear condensed to form high-concentration monodisperse particles, which are then transmitted to the filter 1. Let Then, the particle counter 6 measures the particles in the subsequent stage to measure the collection efficiency of the filter 1.

However, when an organic solvent having a high boiling point as represented by this DOP is used, the organic molecules trapped in the filter 1 at the time of the inspection measurement come out from the filter 1 at the time of actual use after the inspection. It has recently been found that clean air is polluted, that is, TOC (Total Organic Carbon) is polluted.

[0006]

As described above, if the fine particle collector after the inspection, for example, the clean air that has passed through the filter is contaminated by TOC, it is exposed to the TOC in the manufacturing process of the semiconductor device. TO semiconductor wafer
C contamination is transferred, resulting in defective products and deterioration in characteristics.

Therefore, it is desired to carry out a collection inspection so that such TOC contamination does not occur.

The present invention provides a collection inspection method and a collection inspection device which do not cause such TOC contamination.

[0009]

DISCLOSURE OF THE INVENTION The present invention mainly relates to a method for collecting efficiency of a fine particle collector having a function of collecting fine particles floating in the atmosphere, wherein the fine particle collector has fine particles of a sublimable substance. Perform a collection efficiency inspection of.

Further, in the present invention, sulfur is used as the sublimable substance in the above-mentioned method.

Further, in the present invention, in the above-mentioned method, sulfur generated by dissociating a source gas from a sulfur halide is used as the sublimable substance.

Further, in the present invention, an inspection apparatus for inspecting the effect of collecting fine particles is provided with a source gas source 11 having sublimability and a plasma generating section 12 thereof, as shown in an example in FIG. A particulate portion to be inspected, for example, a filter 13 in a clean bench, a passage portion 15 that connects the plasma generation unit 12 and a chamber 14 in which the inspected particulate collector 13 is arranged, and low temperature air is supplied to the passage portion 15. A low temperature air supply source 16 and a high temperature air supply source 17 for supplying high temperature air to the passage portion 15 are provided.

[0013]

According to the collection inspection method and the collection inspection device according to the present invention described above, since the substance having the sublimation property is used in the inspection of the particulate collection effect, this inspection is performed after the inspection. Since the fine particles used for the inspection can be completely eliminated from the fine particle collector 13 by performing the heat treatment on the fine particle collector 13, the case where the fine particle collector 13 is used as a filter of a clean bench, for example, On the contrary, the inconvenience of contaminating the clean air can be completely eliminated.

[0014]

Embodiments of the collection inspection method and the collection inspection device according to the present invention will be described.

Description will be made with reference to FIG. As described above, this apparatus includes a source gas source 11 having a sublimation property, a plasma generation part 12 thereof, an inspected fine particle collector, for example, a filter 13 in a clean bench, a plasma generation part 12 and an inspected fine particle trap. A passage portion 15 that connects the chamber 14 in which the assembly 13 is arranged, a low temperature air supply source 16 that supplies low temperature air to the passage portion 15, and a high temperature air supply source 17 that supplies high temperature air to the passage portion 15 are provided. It has the configuration provided.

Sulfur is used as the source gas of the source gas source 11.
Halogen compounds such as S₂ F ₂ , SF₂ , S
F_Four, S₂ F_Ten, S₃Cl₂ , S₂ Cl₂ , S₂ Br
₂ , SBr ₂ , S₃Br₂ Much sulfur S in the molecule
Contained and easily dissociates in plasma to form free S
The raw material gas to be obtained is used.

Then, the raw material gas is supplied to the plasma generator 1
Send to 2. The plasma generator 12 includes a counter electrode 1 to which a high frequency voltage RF is applied by a high frequency oscillator 18.
2A and 12B, in which the source gas is dissociated to release S particles. The liberated S particles are sent to the passage portion 15 via the first opening / closing valve 19.

On the other hand, clean low-temperature air from a low-temperature air supply source 16 having a low temperature, for example, room temperature or lower, preferably 0 ° C. or lower, is supplied to the passage 15 through the second opening / closing valve 20.

Further, clean high temperature air from a high temperature air supply source 17 having a high temperature, for example, 90 ° C. or higher is supplied to the passage 15 through the third opening / closing valve 21 to the passage portion 15.

Further, a particle counter 22 is provided at a stage subsequent to the sample to be inspected in the chamber 14, for example, the filter 13, that is, downstream of the air flow.

Next, using this apparatus, the sample to be inspected 1 is collected.
The procedure of the method of inspecting the particulate collection effect of No. 3 will be described.

In this case, first, the first and second on-off valves 1
9 and 20 are opened to supply the S particles released from the plasma generating portion 12 to the passage portion 15 and blow low temperature air on the way to the chamber 14. By doing so, the S particles agglomerate well at a low temperature, and thus agglomerate at the confluence of the low temperature air to become S particles having a particle size of, for example, several hundred Å to several μm. At this time, the third on-off valve 21 is in the closed state.

In this state, the air containing S particles is sent to the inspected collecting body 13 arranged in the chamber 14.

Then, the number of particles in the air that has passed through the inspected collector 13 is counted by the particle counter 22.

In this way, the collection efficiency of the sample to be inspected 13 is inspected.

After this inspection is completed, the first and second opening / closing valves 19 and 20 are closed, the third opening / closing valve 21 is opened, and high temperature air is sent to the sample to be inspected 13.
The S fine particles collected in the inspected collecting body 13 are sublimated and disappear.

Next, examples of the method of the present invention will be described.

Example 1 In the above-described method of the present invention, S particles were generated in the plasma generator 12 and the collection efficiency was measured.

The conditions of the plasma discharge in this case were gas: S ₂ F ₂ , flow rate: 30 SCCM pressure: 40 Pa RF: 0.1 W / cm ² .

After the particle measurement was completed, heated clean air at 100 ° C. was sent from the high temperature air chamber supply source 17 to the sample to be inspected (filter) 13 to sublimate all the S particles collected by the filter 13. When this filter 13 was used for a clean bench, S contamination did not occur, let alone TOC contamination.

Example 2 In Example 2, H ₂ gas was added to S ₂ F ₂ gas to cause the reaction of H ^* + F ^* → HF ↑ to occur at the same time, thereby facilitating the generation of S particles. The conditions in this case were gas flow rate = S ₂ F ₂ / H ₂ = 30/10 SCCM pressure; 40 Pa RF; 0.1 W / cm ² .

The embodiment is exactly the same as the first embodiment, but the second embodiment has an effect that S particles are more easily generated.

Example 3 In this Example 3, N ₂ gas was added to S ₂ F ₂ gas to prepare particles of polythiazyl polymer (SN) _x having a more stable bond, and the collection efficiency was tested. Gas flow rate; S ₂ F ₂ / H ₂ = 30/10 SCCM pressure; 40 Pa RF; 0.1 W / cm ^{2 In} this case, since the sublimation temperature is about 130 ° C., heated air of 150 ° C. is supplied from the high temperature air supply source. It was sent to the filter 13 to sublimate the collected (SN) _x particles.

The present invention is not limited to the above-mentioned examples, and various embodiments such as S particles can be generated by microwave discharge can be adopted.

[0035]

As described above, according to the present invention, the trapping efficiency of the trapping target 13 to be detected can be carried out without causing contamination of the trapping target 13, that is, for example, the filter of the clean bench. Even if the collector 13 is used for a clean bench for semiconductor manufacturing, the inconvenience of contaminating clean air can be avoided, and the contamination of the clean air lowers the yield of semiconductor device manufacturing, the deterioration of characteristics, and the reliability. Can be avoided.

[Brief description of drawings]

FIG. 1 is a configuration diagram of an example of an apparatus of the present invention.

FIG. 2 is a configuration diagram of a conventional device.

[Explanation of symbols]

 11 Source Gas Source 12 Plasma Generating Part 13 Inspected Collector 16 Low Temperature Air Supply Source 17 High Temperature Air Supply Source 22 Particle Counter

Claims (4)

[Claims] 1. A collection efficiency inspection method of a fine particle collector mainly having a function of collecting fine particles floating in the atmosphere, wherein the fine particle collector having fine particles of a sublimable substance is subjected to the collection efficiency inspection of the fine particle collector. A collection inspection method characterized by. 2. The collection inspection method according to claim 1, wherein the substance having sublimability is sulfur. 3. The collection inspection method according to claim 1, wherein the substance having sublimability is sulfur generated by dissociating a sulfur halide as a raw material gas and dissociating the same. 4. A sublimation source gas source, a plasma generation part thereof, an inspected fine particle collector, a passage part communicating with the plasma generation part and a chamber in which the inspected fine particle collector is arranged. And a low temperature air supply source for supplying low temperature air to the passage portion, and a high temperature air supply source for supplying high temperature air to the passage portion.