KR20150085280A - Analytical apparatus for gas form adsorbed species - Google Patents

Abstract

The analysis apparatus for adsorbed species in a gas phase according to an embodiment of the present invention includes a reactor wherein the inside thereof may be maintained in a vacuum state, and an inlet window and an outlet window for passing infrared light are coaxially arranged at a side wall; a plasma device connected to the upper surface of the reactor, wherein an internal space unit may be maintained in a vacuum state; a crystal disposed between the reactor and the plasma device, wherein an analyte passes through the surface facing the plasma device; a crystal heating holder fixed to the upper surface of the reactor and controlling the ambient temperature, wherein the crystal is connected to the center thereof; a holder element connected to the crystal heating holder, wherein a groove is formed in a location corresponding to the crystal; a detector detecting the infrared beam outputted from the outlet window; and an analyzer performing qualitative and quantitative analysis of a sample by using the detected beam intensity, wherein the analyzer is characterized by comparing a measurement value when the analyte is introduced to the side of the crystal with a measurement value when reactive gas is introduced and reacted to the material adsorbed to the surface of the crystal after blocking the introduction of the analyte.

Description

Technical Field [0001] The present invention relates to an adsorbent species analyzing apparatus,

The present invention relates to an infrared spectrometer capable of real-time process diagnosis, and more particularly, to an apparatus for analyzing a gaseous adsorbate species.

Internal reflection spectroscopy, also known as Attenuated Total Reflection (ATR) spectroscopy, is a well known technique widely used in infrared (IR) and fluorescence spectroscopy and other spectroscopic sampling methods.

When infrared rays are used as a light source, reflection may occur when infrared rays pass from a dense medium to a less dense medium. The fraction of the incident infrared rays reflected increases when the incident angle is larger. When the incident angle exceeds a certain threshold angle, do. Long-term infrared (MWIR) or mid-infrared (IIR) spectroscopy is the technology of choice when specificity is the most important. However, even though the absorption rate of many materials is very high in the mid-infrared region (e.g., about 3-8 [mu] m) of the electromagnetic spectrum, which is good in terms of sensitivity, it sometimes introduces a sample into the spectrometer in an ideal way, , It is a tricky technology that can only be used if various sampling techniques are developed.

Therefore, it can be regarded as an effective analytical method for thin film analysis and adsorption species analysis, which can be carried out by placing a sample on the surface of a transparent crystalline material having a large refractive index in order to ensure the convenience and accuracy of measurement. In such devices, due to the proper adjustment of the angle of incidence, the radiation passes through the crystal and multiple internal reflections occur within the crystal until it reaches the detector, where absorption and attenuation can occur in each of these internal reflections.

In particular, the ATR spectrum is similar to the normal absorption spectrum, but with the following differences. That is, the ATR spectrum has the same band as the absorption spectrum, but the relative intensity is different, and the radiation penetrates only a few millimeters of the sample. The absorbance depends on the incident angle but is different from the sample thickness. The penetration depth d _p is expressed by the wavelength of the infrared ray, the refractive index of the sample, and the incidence angle of the infrared ray.

Here, λ _c is the wavelength in the crystal λ _c / n _c, θ is incident angle, n _s is the refractive index of the sample, n _c is the refractive index of the crystal.

In this way, in order to understand the physical and chemical properties of chemical vapor deposition materials and to select the most suitable materials, researches using materials such as infrared spectroscopy, chemical vapor deposition Of the total population. However, there is no research on the adsorption behavior of chemical vapor deposition materials on the surface of the wafer in chemical vapor deposition and atomic layer deposition processes.

The present invention relates to a method for analyzing the adsorption behavior of a chemical vapor deposition material by an ATR (Attenuated Total Reflectance) spectrometer by adsorbing a chemical vapor deposition material on a crystal surface serving as a wafer in a vacuum state, An adsorbent species analyzer and an analysis method using the same.

The apparatus for analyzing gaseous species according to the present embodiment includes a reactor in which an interior is kept in vacuum, an incident window through which infrared light enters and exits, and an exit window coaxially disposed on the side wall; A plasma device coupled to an upper surface of the reactor, the inner space being maintained in vacuum; A crystal interposed between the reactor and the plasma device, the crystal being opposed to the plasma device through which the analyte passes; A crystal heating holder coupled to the crystal in the vicinity of the center and having one end fixed to an upper surface of the reactor to adjust an ambient temperature; A holder member coupled to the crystal heating holder and having a groove at a position corresponding to the crystal; A detector for detecting an infrared beam output from the outgoing window; And an analyzer for performing qualitative and quantitative analysis of the sample using the intensity of the detected beam, wherein the analyzer comprises: a measurement value when a substance to be analyzed is introduced into a crystal side; And then comparing the measured value when reacted by introducing the reaction gas into the substance adsorbed on the surface of the crystal.

The plasma apparatus may be connected to a carrier gas supply device for storing a carrier gas, a flow rate control device for controlling a flow rate of the carrier gas, and a precursor accommodating part for storing a precursor material to be analyzed.

The crystal, the crystal heating holder and the upper surface of the fixing portion may all be disposed on the same plane.

The groove may be formed wider than the lower opening where the upper opening is in contact with the crystal.

The crystal has a first surface through which the analyte passes; A second surface spaced a certain distance from the first surface and parallel to the first surface; A third side on which an infrared beam is incident; And

Wherein an area of the first surface is larger than an area of the second surface and the third surface and the fourth surface are provided symmetrically with respect to the center of the crystal, have.

The crystal may be formed of any one of germanium, silicon, AMTIR, ZnSe, and diamond.

The holder member may be provided with a sealing member on a surface thereof to be engaged with the plasma apparatus.

The moving direction of the analyte may be parallel to the moving direction of infrared rays incident on and emitted from the crystal.

According to the present invention, it is possible to grasp the adsorption behavior of the surface of the wafer in chemical vapor deposition and atomic layer deposition by analyzing through various conditions, The characteristics can be obtained in the background of the analyzed data.

FIG. 1 schematically shows an example of an infrared spectrometer according to the present embodiment,
Fig. 2 is an enlarged view of the crystal portion of Fig. 1,
3 is a perspective view of the infrared spectrometer according to the present embodiment,
4 is an exploded perspective view of FIG.

Hereinafter, the present invention will be described with reference to the accompanying drawings.

FIG. 1 is a view schematically showing an example of an infrared spectrometer according to an embodiment of the present invention. FIG. 2 is an enlarged view of a crystal part of FIG. 1, and FIG. 3 is a cross- And FIG. 4 is an exploded perspective view of FIG.

1, a gaseous adsorbent analyzing apparatus using nanoparticle assist according to the present embodiment includes a reactor 110, a detector 120, an analyzer 130, a focusing lens 140, (150).

The reactor 110 may include an incidence window 111, an exit window 116, and a fixing section 113.

The reactor 110 is an FT-IR spectrometer, which is a device for performing qualitative analysis and quantitative analysis by absorbing or transmitting infrared rays to a sample in a solid, liquid, or gas state. Through this analysis, basic information about molecular structure and molecular bonding of compounds can be obtained. Furthermore, if the detector 120 having a port Emission, PbSe, MCT such as the measurement of the near-infrared region (13,300 ~ 4,000cm ^-1), mid-infrared region (4,000 ~ 400cm ^-1), and the far infrared region (400 ~ 10cm ^-1) This is possible.

The reactor 110 may be provided in a substantially rectangular box shape and may have a receiving space having a predetermined space in the inner space. The reaction by-products and / or reactants can be temporarily accommodated in the receiving portion. The fixing part 113 may be formed with a through hole at the center so that the crystal 100 can be detachably fixed (see FIG. 4). In the reactor 110, an incident window 111 and an exit window 116 for infrared incident and exit are provided coaxially with each other, and infrared rays are incident along an optical path composed of a plurality of mirrors arranged in an inner space of the receiving portion. The beam can move. The receiving portion may be temporarily accommodated to enable real-time process diagnosis of reaction by-products and / or reactants. At this time, infrared rays incident on the incident window 111 are refracted and scattered while being in contact with reaction by-products or reactants. By measuring the intensity of the refracted and scattered infrared light, qualitative and quantitative analysis of the sample is possible. Thus, the accommodating portion temporarily accommodates the exhaust gas, etc., and emits it after spectral analysis, so that real-time processing is possible.

Meanwhile, the unillustrated infrared beam may be formed by various methods, and it may be focused by the focusing lens 140 and incident on the incident window 111. Infrared light sources consist of inert solids that are electrically heated to temperatures between 1500 and 2200K. Here, a continuous radiation is emitted. At these temperatures the maximum radiation intensity is obtained between 5000 and 5900 cm ^-1 (2 - 1.7 μm). The intensity gradually decreases toward the long wavelength and reaches 1% maximum at 670 cm ^-1 (15 μm).

The infrared light source may be Nernst incandescent lamp, Globar light source, incandescent light source, mercury arc (ARC), tungsten filament, carbon dioxide laser light source and the like.

The Nernst incandescent lamp consists of a cylindrical rare earth oxide oxide with a diameter of 1-2 mm and a length of about 20 mm. When the platinum wire is sealed at the end of the cylinder and electricity is passed through, a temperature of about 1200 and 2200 K is obtained. Since the resistance decreases with increasing temperature, the light source circuit should be designed to suppress the current. Otherwise, the incandescent lamp will heat up rapidly and be destroyed.

The Globar light source is a silicon carbide rod with a length of about 50 mm and a diameter of 5 mm. It is electrically heated and the resistance has the advantage of having a positive coefficient. The spectral energies of Globar and Nernst incandescent lamps are much the same, except that the globars provide a much larger energy area below 5 μm.

The incandescent light source is a tightly wound nichrome wire spiral that is somewhat less intense than Globar and Nernst light sources, but has a long life and can heat up to 1100K with current.

The mercury arc (ARC) consists of a quartz tube filled with mercury vapor at pressures greater than one atmosphere. Passing electricity through the mercury vapor forms an internal plasma light source that provides a continuous radiation in the far infrared region.

The tungsten filament can be a convenient light source in the near infrared region of 4000 to 12,800 cm ^-1 (2.5 to 0.78 μm).

The CO2 laser source is a variable wavelength CO2 laser that measures the concentration of air pollutants and is used as an infrared light source to quantify chemical species in aqueous solutions. Carbon dioxide lasers emit radiation in the 900 - 1100 cm ^-1 area consisting of about 100 closely spaced discontinuities. Although the range of available wavelengths is limited, the 900 to 1100 cm ^-1 region has a particularly large absorption band. Thus, this light source is useful for the quantitative analysis of numerous chemical species such as ammonia, butadiene, benzene, ethanol, nitrogen dioxide, trichloroethylene and the like.

The first and second surfaces 100a and 100b are formed so that the first and second surfaces 100a and 100b have a larger area than that of the second surface 100b, May be disposed on the side surface of the base 100b. At this time, the slopes of the third and fourth surfaces 100c and 100d are the same, and they may be provided to be mutually symmetric with respect to the center of the crystal 100. The crystal 100 may be formed of various materials. Generally, germanium, silicon, AMTIR, ZnSe, diamond, or the like can be used. Any material that causes total internal reflection upon entering the infrared ray Available. Physical properties according to the material of the crystal 100 are shown in the following table.

Material ATR spectral range (cm ^-One ) Refractive
 index Depth of pentration (μ)
(at 45 ° C & 1000 cm ^-One ) Max temp In Air
 [° C] Uses Germanium 5,500 to 675 4 0.66 125 Good for most samples, especially samples, such as dark polymers Silicon 8,900 - 1,500
&
360 ~ 120 3.4 0.85 300 Resistant to basic solutions AMTIR 11,000 to 725 2.5 1.77 Very resistant to acidic solution ZnSe 15,000-650 2.4 2.01 300 General use Diamond 25,000 - 100 2.4 2.01 750 Good for most samples. Extremely caustic or hard samples

A precursor in the form of gas or liquid may be supplied to the upper surface of the first surface 100a together with the carrier gas to move as shown in FIG. 2, and the nanoparticles 1 may be arranged as necessary The nanoparticle 1 may be made of a material that is easily adsorbed to the precursor. However, since the nanoparticle 1 is not necessarily required, it may be omitted. In this case, the crystal 100 may be used while being changed depending on the kind of the precursor. The properties of the crystal 100 according to the material change are shown in Table 1 above.

The second surface 100b may be disposed in the direction toward the inside of the accommodating portion, and may be disposed inside the accommodating portion. The infrared rays irradiated to the incident window 111 are reflected by the first and second surfaces 100a and 100b and are incident on the flat mirror 150 through the exit window 116 along the optical path shown in FIG. And the infrared rays may be frequency-analyzed through the detector 120 and the analysis device 130. [

The crystal 100 according to the present embodiment is applied to the multiple reflection ATR method. When infrared rays are incident on a crystal having a high refractive index like the above-described materials and the first and second surfaces 100a and 100b alternate And the reflected light is emitted from the opposite side. Therefore, when infrared rays are incident on the third surface 100c so that the incident angle is 35 to 50 degrees and are totally reflected on the first and second surfaces 100a and 100b alternately, the infrared rays are incident on the first surface 100a After being partially absorbed by the analyte, it is emitted to the fourth surface 100d. Thus, the absorption spectrum can be obtained by measuring this. In general, the total reflection on the first and second surfaces 100a and 100b can be configured to occur 11 to 25 times.

Meanwhile, the crystal 100 may be coupled to the fixing portion 113 by the crystal heating holder 101, as shown in FIG. 2 and FIG. The crystal heating holder 101 can control the temperature environment according to the experimental conditions by applying heat to the crystal 100. The crystal heating holder 101 is formed with a seating groove 101a having a shape corresponding to that of the crystal 100 and a first surface 100a of the crystal 100 is formed in the center of the crystal heating holder 101 And can be disposed so as not to protrude from the upper surface. At this time, the first surface 100a of the crystal 100, the upper surface of the crystal heating holder 101, and the upper surface of the fixing portion 113 are all formed to form the same surface. The crystal heating holder 101 may serve to heat the inflow gas or the analytical material in order to vaporize the inflowing gas or the analyte when it is in a liquid state.

When the crystal 100 is installed on the upper side of the fixing part 113 with the crystal heating holder 101 interposed therebetween, the fixing part 113 and the holder member 102 are coupled to the upper side of the crystal heating holder 101 .

One end of the holder member 102 is fixed to the fixing unit 113 while the other end thereof is fixed to the plasma device 115. The other end of the holder member 102 is coupled with the crystal 100 A concave groove 102a is formed and a space having a predetermined volume can be formed on the upper surface of the first surface 100a which is the upper surface of the crystal 100. [ At this time, the space portion can maintain a vacuum state together with the plasma formed by the plasma device 115, and the gas adsorption paper to be analyzed can pass through. A sealing member 103 of rubber or silicon is protruded from the recess 102a of the holder member 102 so that the sealing member 103 can be connected to the plasma apparatus 115 in a vacuum state do.

The plasma apparatus 115 includes a body 115a including a plasma electrode and first and second ports 115b and 115c, as shown in FIG. The body 115a is capable of forming a plasma in the internal space portion by applying external power. The body 115a is connected to other vacuum components such as a vacuum pump, a vacuum measurement gauge, a bellows, a valve and a vacuum line to form a vacuum system, and a surface of the crystal 100 installed in the ATR and the recess 102a, Can be formed in a vacuum.

The first port 115b is connected to a carrier gas supply device (not shown), a flow rate regulator such as an MFC, and a precursor accommodating portion, and can supply a precursor of a substance to be analyzed and a carrier gas to the space portion. At this time, plasma may or may not be used depending on the type of the substance to be analyzed. When the plasma is used, the gas to be generated should be introduced.

The second port 115c is connected to the exhaust line to discharge gas that is not adsorbed to the crystal 100 to the outside. At this time, a rotary pump and a pressure gauge may be installed in the exhaust line.

The detector 120 is a device for detecting infrared rays, and generally there are three types.

Thermal detectors, pyroelectric detectors and photoconducting detectors are used. In FT-IR equipment, mainly fatigue electric sensors and photoelectric sensors are mainly used.

The thermal sensor is used to detect all infrared rays except for the infrared wavelength of a short wavelength. In these devices, the radiation is absorbed by the small black body and the resulting rise in temperature is measured.

A fatigue electric sensor is composed of a single crystal wafer of fatigue electric material which is an insulator having special thermal and electrical properties. Triglycine sulfate is the most important fatigue substance used in the production of infrared detectors. This detector is used in most FT-IRs because it has a sufficiently fast response time to track changes in the time-function signal from the interferometer.

The photoconductivity sensor consists of a thin film of semiconductor material, such as lead sulfide, cadmium telluride mercury photoconductor, or indium antimonide, which is mounted on a nonconductive glass surface and protects the semiconductor from the atmosphere. Sealed in a vacuum tube. When these materials absorb the radiation, the nonconductive atoms cause the electrons to move to a state of high energy conduction, resulting in a decrease in the resistance of the semiconductor. In general, when a photoconductor is connected in series with a voltage source and a load resistor, the voltage drop across the load resistor can indicate the intensity of the emitted light. Photoelectric sensors are often used in spectrometers connected to gas chromatography.

Hereinafter, an analytical method using the adsorbent species analyzer in a gaseous state utilizing the nano-particle assist as described above will be described.

First, the valve blocking the carrier gas storage tank such as argon (Ar) is opened to discharge the carrier gas. At this time, it is possible to supply a precise amount of carrier gas necessary for the experiment to the precursor storage unit by using a flow rate control unit such as an MFC. If the precursor material is a gaseous phase, the precursor material to be analyzed may be vaporized by heating the crystal 100 using the crystal heating holder 101 or the like in the case of a liquid phase. In this way, the analytical conditions can be adjusted to correspond to the process conditions in a state where the analytes are introduced into the surface of the crystal (100). At this time, the information to be adjusted may be process temperature, pressure, degree of vacuum, etc., but it is not limited thereto, and the user of the apparatus may vary according to the measured value.

At the same time, infrared rays are irradiated toward the incident window 111 from an infrared ray irradiator (not shown) so that the adsorbed paper adsorbed on the first surface 100a, which is the surface of the crystal 100, can receive the infrared ray. At this time, the irradiated infrared light travels along a predetermined optical path, is incident on the third surface 100c, and is totally reflected on the first and second surfaces 100 and 100b inside the crystal 100, And output to the four sides 100d. At this time, since the infrared absorbing paper adsorbed on the actual surface absorbs the infrared light in the infrared energy region, the infrared light output through the output window 116 is different from the energy absorbed by the adsorbing species, Can be detected.

Meanwhile, after analyzing the analytes by the above-mentioned process, after the flow of the analyte is blocked, the reaction gas is introduced into the material adsorbed on the surface of the crystal 100 and reacted, Analyze.

According to the present invention, the adsorption behavior on the surface of the wafer in the chemical vapor deposition and atomic layer deposition processes can be analyzed through various conditions and the characteristics of the thin film to be desired in the actual deposition process can be confirmed.

The embodiments of the present invention described above and shown in the drawings should not be construed as limiting the technical idea of the present invention. The scope of protection of the present invention is limited only by the matters described in the claims, and those skilled in the art will be able to modify the technical idea of the present invention in various forms. Accordingly, such improvements and modifications will fall within the scope of the present invention as long as they are obvious to those skilled in the art.

100; Crystal 100a; The first side
100b; A second surface 100c; Third Side
100d; A fourth surface 101; Crystal heating holder
102; A holder member 103; The sealing member
111; Incidence window 115; Plasma system
116; Exit window 120; Detector
130; Analyzer 140; Focusing lens
150; Flat mirror

Claims (8)

A reactor in which an interior is kept in vacuum, an incident window through which infrared light enters and exits and a discharge window coaxially disposed on the side wall;
A plasma device coupled to an upper surface of the reactor, the inner space being maintained in vacuum;
A crystal interposed between the reactor and the plasma device, the crystal being opposed to the plasma device through which the analyte passes;
A crystal heating holder coupled to the crystal in the vicinity of the center and having one end fixed to an upper surface of the reactor to adjust an ambient temperature;
A holder member coupled to the crystal heating holder and having a groove at a position corresponding to the crystal;
A detector for detecting an infrared beam output from the outgoing window; And
And an analyzer for performing qualitative and quantitative analysis of the sample using the intensity of the detected beam,
The analyzer comprises:
A measurement value at the time of introducing the analyte into the crystal side and a measurement value at the time of reacting by introducing the reaction gas into the substance adsorbed on the surface of the crystal after the inflow of the analyte is blocked, Adsorption species analyzer.
The plasma processing apparatus according to claim 1,
A carrier gas supply device for storing a carrier gas, a flow rate control device for controlling a flow rate of the carrier gas, and a precursor accommodating part for storing a precursor material to be analyzed.
The method according to claim 1,
Wherein the crystal, the crystal heating holder, and the upper surface of the fixing portion are all disposed on the same plane, and an analyzer using the same.
The method according to claim 1,
Wherein the groove is formed to be wider than an opening of a lower portion where an upper opening is in contact with the crystal, and an analyzing apparatus using the same.
The method of claim 1,
A first side through which the analyte passes;
A second surface spaced a certain distance from the first surface and parallel to the first surface;
A third side on which an infrared beam is incident; And
And a fourth surface from which an infrared beam is emitted,
Wherein the area of the first surface is larger than the area of the second surface, and the third surface and the fourth surface are symmetrical with respect to the center of the crystal, and an analyzer using the same.
The method of claim 1,
Germanium, silicon, AMTIR, ZnSe, or a diamond material.
2. The holder according to claim 1,
Wherein a sealing member is provided on a surface of the plasma apparatus which is engaged with the plasma apparatus.
The method according to claim 1,
The moving direction of the substance to be analyzed is an adsorbing species analyzer in a gaseous state parallel to the moving direction of infrared rays incident on and emitted from the crystal,

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