JP2006208136A - Collector for analyzing contaminant - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a collector for analyzing a contaminant constituted so that a molecular chemical contaminant is selectively collected from an analyzing gas and the collection of the contaminant is performed with the elapse of time without fixing/restricting an analyzing method by providing a base material formed of this substance as the surface of a photomask to a collection part without using the photomask in order to analyze the surface contaminant of the photomask. <P>SOLUTION: In the collector for analyzing the contaminant equipped with a suction part for sucking the analyzing gas with the elapse of time and the collection part for collecting the molecular chemical contaminant with the elapse of time, the collection part is composed of the base material and the surface substance layer formed on the surface of the base material, the surface substance layer comprises this substance as the surface of a desired material, the collection part is equipped with a means for selectively collecting the contaminant and this selective collection means of the contaminant is constituted so as to selectively collect the contaminant on the surface of the surface substance layer by heating or cooling the surface of the surface substance layer using a Peltier element or a lamp heater. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to gas-solid surface interaction, chemical interaction, physics for analyzing and detecting contaminants that affect the manufacture of electronic products, and that molecular contaminants suspended in the gas adhere to the manufacturing material over time. The present invention relates to a pollutant analysis collection device for analyzing pollutants using mechanical interaction.

  Many electronic products, such as semiconductors, flat panel displays, medical and food manufacturing processes and technologies, many of which work in a clean room. Conventionally, in a clean room, particulate dust (floating particles) has been regarded as a problem, and a physical solid shape having a certain size has been a target of restriction. In recent years, air-borne molecular contamination (AMC, hereinafter referred to as AMC) in a gas has adhered to the surface of a manufacturing material by chemical interaction, and surface molecular contamination (SMC). , Hereinafter referred to as SMC), causing problems that cause performance degradation and product defects. Such SMC problems such as resist T-topping, imperfect epitaxial growth, heterogeneous oxide layer growth, heterogeneous corrosion reaction in the corrosion process, poor adhesion of wiring materials, etc. This causes a failure to obtain normal electrical characteristics as an electronic product. In addition, it can be cited as factors such as optical performance degradation effects such as “hazing” in the optical device industry, and wear degradation effects due to friction between the rotating disk and the reading probe in hard disk drives.

  Various AMCs that cause harmful SMCs are known in the art in the clean room and are grouped in SEMI standards F21-95 class A, B, C, D, for example, in the semiconductor field, for example in the United States.

  As for the supply source of AMC, for the supply gas that has been treated outside from the clean room, the exhaust gas from automobiles contained in the outside air and various industrial waste and molecular contaminants of evapotranspiration from animals and plants are sufficiently filtered. It is not treated and flows into the clean room, or in the clean room, the constituent material of the particle collection filter, the molecular contaminants from the airtight sealant material, or the installed manufacturing equipment, the gas release from the manufacturing material used, etc. Can be mentioned. Still other sources include physiological activity emissions from breathing from workers in a clean room, or outgassing from clothing or the like.

  Analysis and monitoring have been devised for monitoring these SMCs. However, for example, there is no single device or apparatus that analyzes or monitors all the classifications of the SEMI standards F21-95 classes A, B, C, and D exemplified above. The current technology has a problem only with a device that detects only specific physical species such as organic matter and inorganic matter.

  In general, components at the molecular level contained in the gas phase are adsorbed and adhered to the solid surface in relation to the physicochemical properties of the substance, such as vapor pressure and molecular structure, and the molecular bonding state and temperature of the solid surface. Adsorption / adhesion amount can be obtained by back-calculating the concentration in the gas phase by measuring the very small amount adsorbed on the solid surface because some of the substance is in equilibrium adsorbed in proportion to the concentration in the gas. I can do it.

In the existing monitoring technology, as a method for obtaining specific information on chemical species, a sample of an analysis gas is temporarily collected on an adsorption medium and a method of performing chromatogram analysis or a quartz crystal microbalance (Quartz Crystal Microbalance) is used. :
There is a technique using QCM) or surface acoustic wave (SAW). This method is based on the principle of converting the frequency change corresponding to the amount of the substance accumulated on the sensor surface as the amount of contamination.

  In addition, in the existing apparatus, there is an application (see Patent Document 1) in which a thermal action is used as a principle for selecting a substance to be attached to the sensor surface and a gas heater is provided in the upstream part of the sensor. However, gas heating is insufficient in terms of selectivity utilizing the boiling point of contaminants. This is because the temperature of the sensor surface should be selected for contaminant selection. It is essential that the sensor surface has boiling point selectivity, and the sensor surface temperature needs to be the boiling point of the contaminant.

  As another method for controlling substances adhering to the sensor surface, in the semiconductor manufacturing industry, in order to isolate the material from atmospheric contamination, the material is stored in a container, and degassing generated from the material of the container is performed. There is an application (see Patent Document 2) in which a sensor that detects only the degassed component is mounted in a container and the sensor is built in the container.

  In any of the above-mentioned Patent Documents 1 and 2, the analysis method is fixed and limited. Also, the selectivity of the SMC material is insufficient. Furthermore, it does not cover collection of reaction products with pollutants when a gas is present in a light source, electron beam, or radiation environment of a specific wavelength, for example. There are various problems as described above.

The known literature is described below.
JP 2004-69686 A JP 2004-47929 A

The object of the present invention is not to use a photomask to analyze the surface contaminants of the photomask, but to provide a base material on which the same material as the surface of the photomask is formed in the collecting part, and the analysis method is fixed -To provide a collection device for contaminant analysis, which is not limited and can selectively collect molecular chemical pollutants from an analysis gas and can collect contaminants over time. .

  The invention according to claim 1 of the present invention includes a suction part for sucking molecular chemical contaminants in an analysis gas (hereinafter referred to as analysis gas) over time, and molecular contamination sucked by the suction part. A pollutant analysis collection device including a collection unit for collecting substances over time, the collection unit forming a substrate and a surface material layer on the surface, the surface material layer, It is a collection device for contaminant analysis characterized by comprising the same substance as the desired material surface.

  The invention according to claim 2 of the present invention is the contaminant analysis collection apparatus according to claim 1, wherein the substrate is made of metal.

  In the present invention, it is possible to arbitrarily select a plurality of types of surface material layers such that the surface material layer to be formed is made of the same material as the desired material surface on the base material of the collection part.

  The invention according to claim 3 of the present invention is such that the collection part does not receive contamination by a gas other than a gas for analysis and means for selectively collecting a contaminant by physical or chemical reaction. The contaminant analysis collection device according to claim 1, further comprising a protection means.

  The invention according to claim 4 of the present invention is characterized in that the means for selectively collecting the contaminants contaminates the surface of the surface material layer by heating or cooling the surface of the surface material layer to a specific temperature. 4. The contaminant analysis collection apparatus according to claim 3, wherein the substance is selectively collected.

  The invention according to claim 5 of the present invention is characterized in that the means for selectively collecting the contaminant is the surface material layer by irradiating the analysis gas near the surface of the surface material layer with a light beam having a specific wavelength. 4. The contaminant analysis collection apparatus according to claim 3, wherein contaminants are selectively collected on the surface of the contaminant analysis apparatus.

  The invention according to claim 6 of the present invention is characterized in that the means for selectively collecting the contaminant is the surface material layer by irradiating the analysis gas near the surface of the surface material layer with radiation of a specific wavelength. 4. The contaminant analysis collection apparatus according to claim 3, wherein contaminants are selectively collected on the surface of the contaminant analysis apparatus.

  In the present invention, it is possible to selectively collect contaminants on the surface of the surface material layer by heating or cooling the surface of the surface material layer to a specific temperature, or by irradiating light of a specific wavelength.

  If the collection device for contaminant analysis of the present invention is used, it adheres to the collection part which formed the same surface material layer as the contaminated material surface from the molecular contaminant (AMC) present in the analysis gas. For each specific component of the composition of the substance (SMC), by heating or cooling the surface material layer to its boiling temperature, or arbitrarily setting the environment under irradiation with specific radiation, etc., only predetermined pollutants Can be selectively collected over time, and various components of the analysis gas can be collected comprehensively and used for analysis and evaluation of molecular contaminants in the analysis gas.

  According to the present invention according to claim 1, by forming the same material as the surface of the photomask on the surface material layer of the collection part, a plurality of materials can be formed on the surface material layer instead of using a photomask. For example, contaminants can be collected over time using a quartz material and a light shielding film material.

  FIG. 1 shows a schematic structure of the contaminant analysis collection apparatus of the present invention. FIG. 1 is a perspective view, and a collection device 100 includes a collection reel 10 and a collection unit of a reel driving device 20 that are wound up, and an exhaust pump 30, a suction pipe 40, a suction port 50 of a suction unit, An intake valve 60, an exhaust port 70, and an exhaust valve 80 are configured. A gas (analysis gas) 900 containing a contaminant is sucked from the suction port 50 by the exhaust pump 30 and part of the surface of the collection reel 10 passing through the openings 41 </ b> A and 41 </ b> B provided in the suction pipe 40. The exposed surface 10A is reached, and after the contaminant is attached, it is discharged from the exhaust port 70. The collection reel 10 is continuously swept at a predetermined speed as shown by an arrow in the figure or intermittently wound at regular intervals as shown by arrows in the figure, and a pollutant collecting operation that changes with time is performed. . Further, the reel driving device 20, the exhaust pump 30, the intake valve 60, and the exhaust valve 80 are controlled by a reel drive controller 310, an exhaust pump controller 320, and a valve opening / closing controller 330, respectively. Integrated control.

As shown in the reference diagram of FIG. 1, a surface material layer 2 is formed on at least one surface of the substrate 1 of the collection reel 10, and the surface material layer is composed of the same material as the material to be analyzed for contamination. It is desirable. For example, when it is desired to analyze the surface contamination of the photomask, the photomask is formed with an inorganic material, an inorganic oxide, a metal, a metal oxide, or a mixture of a plurality of materials, and the surface material layer 2 is made of silicon, SiO. , Cr, CrO, Ta, TaSi, TaSiO, TaSiN, TaBN, CrN, CrON, Mo, MoSi, Zr, ZrSi, MoZrSi, or the like. Sputtering, vapor deposition, atomic layer accumulation, coating, etc. can be used to form the surface material layer.

  2A and 2B are plan views showing an example of the details of the collection reel 10. The reference drawing is a sectional side view. In FIG. 2A, protrusions 11 are continuously formed on one side surface of the collection reel 10, and function as a spacer that prevents adhesion substances from being transferred to the opposite surface due to close contact between the front and back during winding. FIG. 2B is an example of a continuous rib shape.

  FIG. 3 is a partially enlarged view of the YY ′ plane in FIG. 1, which is a structural cross section that enables the selectivity of the contaminant to be set to an arbitrary boiling point temperature, and will be described below with reference to FIG. 3. To do. The boiling point control means is, for example, a Peltier element 210 that can both heat and cool the exposed surface 10A. It is installed inside the temperature control unit 200 installed in FIG. 3B). The temperature on the exposed surface 10A is measured with a thermometer 220 on the measurement surface made of the same material as the collection reel 10 and placed at the same distance α between the Peltier element 210 and the exposed surface 10A. The thermometer 220 feeds back the Peltier element 210 to the temperature controller 230 so as to reach a predetermined temperature, and controls the temperature. When the boiling point control is only heating, a heat ray heater or an infrared lamp heater may be used instead of the Peltier element 210.

  When utilizing the boiling point selectivity, the substrate 1 and the surface material layer 2 are heated or cooled. It is known that the surface of stainless steel can be smoothed by electropolishing or the like, and the effective surface area can be reduced. When stainless steel is used for the base material 1 of the collection reel 10, the base material 1 has an effect of reducing the effective surface area, reducing the outgas emission from the material itself by heating and cooling, and has little influence on the collected material. Convenient.

  Furthermore, when using the magnetic properties of contaminants as selectivity, stainless steel has the advantage that non-magnetic and magnetic properties can be selected by the substrate itself.

  Furthermore, since metals such as stainless steel have no electrostatic charge, there is an advantage that no repulsion or suction action is given to the charged charges (positive and negative) of the contaminants.

  For metals other than stainless steel, examples of selectivity include TiO exhibiting catalytic properties, and Ag, Au, etc. for corrosive substances.

  FIG. 4 shows a cross-sectional view similar to FIG. FIG. 4 shows an embodiment in which collection of a reaction product with the material of the collection reel 10 when the pollutant is in a light source, electron beam, or radiation environment of a specific wavelength is intended. The light source 410, the electron beam source 420, and the radiation source 430 may be irradiated to the area of the exposed surface 10A. In this embodiment, the irradiation unit 400 is installed in the suction tube 40, and the light source 410 or the electron beam source 420 and the radiation source 430 are installed inside. As in FIGS. 3A and 3B, the irradiation unit 400 is arranged on one or both sides immediately above the exposed surface 10A. The source of the light source 410 is a laser oscillator, generally a deuterium lamp having an emission line spectrum in the vacuum ultraviolet region, a xenon lamp having an emission line spectrum in the far ultraviolet region, or a continuous wavelength in the near ultraviolet to visible light or near infrared region. A halogen lamp having a band or the like is applicable. The light source 410, the electron beam source 420, and the radiation source 430 may further include wavelength selection means such as a filter 440 or a diffraction grating optical system 450 therein. The irradiation unit 400 may be disposed on both the upper and lower surfaces as in FIG.

FIGS. 5A and 5B show an embodiment in which protective means is provided so that the collected collection reel 10 is not contaminated before and after collection. 5A is a top view and 5B is a side sectional view thereof. The feeding side cassette 510A and the receiving side cassette 510B having an airtight structure are hermetically connected to the suction pipe 40 so as to be detachable. The suction pipe 40 is provided with air-tight ports 42A and 42B that enable both cassettes 510A and 510B to be air-tightly connected. Both cassettes 510A and 510B are provided with opening and closing doors 520A and 520B. The open / close doors 520A and 520B use an O-ring 590 to ensure airtightness. Both cassettes 510A and 510B are supplied with an inert gas, for example, nitrogen gas, which does not contain impurities and does not show a chemical reaction with the collected material. The supplied gas is supplied from valves 550A and 550B through a heat exchanger 540 that adjusts the flow rate by a flow rate adjuster 530 and adjusts the temperature to at least the boiling point or less in order to prevent thermal desorption of the collected substance. At the same time as the flow rate, the supply gas is controlled by the pressure gauges 560A and 560B so as to keep the inside of both cassettes 510A and 510B at a positive pressure with respect to the outside. When the positive pressure is maintained, the opening / closing doors 520A and 520B are opened. The collecting reel is sent out from the feeding-side cassette 510A by the reel driving device 20, passes through the airtight ports 42A and 42B, the collecting reel 10 is taken up and stored in the receiving-side cassette 510B on the opposite side, and the collecting is completed. . Removal of both cassettes 510A and 510B closes the open / close doors 520A and 520B and the valves 550A and 550B. Next, when the connection valves 570A and 570B are closed, the feeding side cassette 510A and the receiving side cassette 510B are hermetically sealed. What is necessary is just to remove both cassettes 510A and 510B from the connection joints 580A and 580B.

  In the above embodiment shown in FIG. 5, the case of using the pollutant analysis collecting apparatus of the present invention under atmospheric pressure has been described. However, the pollutant floating in the decompressed gas is collected by connecting to the decompressing apparatus. The case will be described with reference to FIG. When inhaling gas under reduced pressure, the intake port 50 may be airtightly connected to the decompression device 710 via a gate valve 720 or the like. Since the feeding side cassette 510A and the receiving side cassette 510B are hermetically connected to the suction pipe 40 as described above, they are hermetically sealed through the hermetic ports 42A and 42B. Therefore, ambient gas outside the decompression device 710 does not come into contact with the collection reel 10. When the collection reel 10 has been wound from the feeding cassette 510A to the receiving cassette 510B, the airtight ports 42A and 42B and the open / close doors 520A and 520B are closed. Next, the receiving side cassette 510B is removed from the suction tube 40. At the stage of removal, the inside of the receiving cassette 510B is vacuum. When it is desired to fill with an inert gas such as nitrogen, it may be supplied until the differential pressure gauge 560B reaches atmospheric pressure or higher via the heat exchangers 540 and 550B, the connection joint 580B and the connection valve 570B as described in FIG.

  Generally, the decompression environment is divided into viscous flow, intermediate flow, and molecular flow based on the mean free process. Since the movement of gas molecules in a reduced-pressure environment has a different molecular velocity depending on the degree of vacuum, the volume of gas consumed for collection is different from atmospheric pressure, and the opportunity for contaminants to contact the exposed surface 10A of the collection reel 10 (efficiency) ) Should be considered. It is necessary to select an exhaust pump 30 having an exhaust capability below the vacuum level of the decompression device 710, and the contact opportunity (efficiency) may be adjusted by the winding time of the collection reel 10.

  According to the above description, in order to collect the substance (SMC) adhering to the surface material layer of the collection medium that is the same as the desired material surface among the molecular contamination (AMC) existing in the gas, By setting the surface temperature arbitrarily, molecular chemical contaminants can be collected continuously and selectively, and a contaminant analysis collection device that can be used for various analysis and evaluation means has been realized.

It is explanatory drawing which shows the 1st Example of the collection apparatus for contaminant analysis of this invention. AB is a partial view of the present invention, and is an explanatory view showing a second embodiment. AB is the elements on larger scale of this invention, and is a sectional side view which shows a 3rd Example. It is the elements on larger scale of this invention, and is a sectional side view which shows a 4th Example. It is drawing which shows 5th Example of the collection apparatus for contaminant analysis of this invention, A is a top view, B is a sectional side view. It is a top view which shows the 6th Example of the collection apparatus for contaminant analysis of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Base material 2 ... Surface substance 10 ... Collection reel 10A ... Exposed surface 20 ... Reel drive device 30 ... Exhaust pump 40 ... Suction pipe 41A ... Opening part 41B ... Opening part 42A ... Airtight port 42B ... Airtight port 50 ... Suction port 60 ... Intake valve 70 ... Exhaust port 80 ... Exhaust valve 100 ... Collection device 200 ... Temperature control unit 210 ... Peltier element 220 ... Thermometer 230 ... Temperature controller 300 ... Central controller 310 ... Reel drive device 320 ... Exhaust pump control 330 ... Valve switch 340 ... Temperature controller 400 ... Irradiation unit 410 ... Light source 420 ... Electron beam source 430 ... Radiation source 440 ... Filter 450 ... Diffraction grating optical system 510A ... Sending side cassette 510B ... Receiving side cassette 520A ... Opening / closing door 520B ... Opening / closing door 530 ... Flow rate regulator 540 ... Heat exchanger 550A ... Valve 550B ... Valve 560 ... pressure gauge 560B ... pressure gauge 570A ... valve 570B ... valve 580A ... connection joint 580B ... connection joint 590 ... O-ring 710 ... decompressor 720 ... gate valves 900 ... gas containing contaminants

Claims (6)

  A suction part for sucking molecular chemical contaminants from analysis gas (hereinafter referred to as analysis gas) with time, and a collection part for collecting molecular contaminants sucked by the suction part with time The collection device for pollutant analysis, comprising: a collecting portion forming a base material and a surface material layer on the surface thereof, wherein the surface material layer is made of the same material as a desired material surface. Characteristic collection device for contaminant analysis.   The said base material consists of metals, The collection apparatus for contaminant analysis of Claim 1 characterized by the above-mentioned.   The said collection part is equipped with the means to selectively collect contaminants by physical or chemical reaction, and the protection means to prevent contamination by gas other than the gas for analysis, It is characterized by the above-mentioned. Item 3. The collection device for contaminant analysis according to Item 1 or 2.   The means for selectively collecting the contaminants selectively collects contaminants on the surface of the surface material layer by heating or cooling the surface of the surface material layer to a specific temperature. The collection device for contaminant analysis according to claim 3.   The means for selectively collecting the contaminants selectively collects the contaminants on the surface of the surface material layer by irradiating the analysis gas near the surface of the surface material layer with a light beam having a specific wavelength. 4. The contaminant analysis collection apparatus according to claim 3, wherein   The means for selectively collecting the pollutant selectively collects the pollutant on the surface of the surface material layer by irradiating the analysis gas near the surface of the surface material layer with radiation of a specific wavelength. 4. The contaminant analysis collection apparatus according to claim 3, wherein

Images