JPH11295225A - Method and device for sensitively and quickly analyzing phosphor and boron in silicon material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method and device that sensitively and quickly analyze phosphor and boron in a silicon material. SOLUTION: A silicon material is directly inserted into high-temperature plasma for excitation light emission, each light emission intensity of phosphor, the background of the phosphor, boron, the background of the boron, and silicon is measured, light emission intensity ratio is obtained, where the light emission intensity is shown by the expressions of light emission intensity ratio = (the light emission intensity of the phosphor - the light emission intensity of the background of the phosphor)/(the light intensity of the silicon) (I) and light emission intensity ratio = (the light emission intensity of the boron - the light emission intensity of the background of the boron)/(the light intensity of the silicon) (II), and phosphor concentration and boron concentration are obtained according to the calibration curve of the light emission intensity ratio, the light emission intensity ratio being obtained in the same manner by the silicon material where the phosphor concentration and the boron concentration are known, the phosphor concentration, and the boron concentration.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for analyzing phosphorus and boron in a silicon material such as a high-purity silicon material used for solar cells, semiconductors and electronic materials, and more particularly to a method for analyzing a trace amount of phosphorus and a trace amount of boron in a silicon material. Phosphorus in silicon material, which can accurately and quickly determine
The present invention relates to a method and an apparatus for analyzing boron with high sensitivity and high sensitivity.

[0002]

2. Description of the Related Art Phosphorus has higher excitation energy and ionization energy than other metal elements.
The analytical sensitivity of the ICP analysis method is poor, and direct analysis cannot be applied to trace levels below the ppm level. The same applies to the analysis of phosphorus in silicon materials.For example, despite the high analysis requirements for phosphorus as an element that has a significant effect on product characteristics in silicon wafers and solar cells, the proposed high-sensitivity analysis method is Few.

[0003] As a method for analyzing phosphorus in silicon material,
As an instrumental analysis method, an infrared absorption method was applied to silicon wafers [BOKolbesen: Appl. Phys. Letters, 27, 353
(1975)] and a photoluminescence method [Michio Tajima: Applied Physics, 47, 376 (1978)] have been studied and established, but the former is intended to make the light input / output surface of the sample flat and smooth. The sample preparation is complicated and takes a long time, while the latter is
There is a problem in that the apparatus itself is large-scale and analysis requires a long time of about half a day.

On the other hand, as a method of analyzing a trace amount of boron in a high-purity silicon material, a sample is generally melted with alkali hydroxide or dissolved under pressure with a solution thereof to form a solution, which is then subjected to electrolysis or extraction. After being concentrated by the method, a method of quantification by a solution analysis method such as a wet analysis method or an radio frequency plasma (ICP) analysis method is used. However, these wet analysis methods require a long time (several hours or more) for preparation and measurement of a sample solution, and thus cannot respond to rapid analysis requirements such as on-site analysis at a production site.

In addition, a method has been studied and reported in which a sample placed in a graphite cup is directly inserted into plasma in ICP emission spectrometry, which is a normal solution analysis method, to quickly analyze impurity elements therein. [EDSalin, G. Horlick: Anal.Che
m., 51, 2284 (1979)]. Examples of the application of the direct sample insertion method described above to solid samples include biological and environmental samples [M. Abuduah,
T.Hasegawa, H.Haraguchi: Spectrochim.Acta, 39B, 1129 (1
984)] and metal samples such as Ni-based alloys [CWMcleo
d, PAClarke, DJMowthorpe: Spectrochim.Acta, 41B, 6
3 (1986)], but its application to the trace region below ppm and silicon material analysis has not been studied.

Since boron has a high boiling point (3927 ° C.) and easily forms non-volatile carbides with graphite as a sample cup material, it is difficult to detect boron with high sensitivity simply by heating in plasma. Can not. Silver chloride (AgCl) and polyfluoroethylene (PTFE) were added to convert these elements into low-boiling halides in order to promote the atomization of refractory elements such as boron.
[G.Zaray, JACBroekaert, F.Leis: Spectrochim.Acta, 4
3B, 241 (1988)].

However, this method is complicated in operation, and the influence of background and impurities caused by the halogenating reagent itself cannot be ignored. Furthermore, since the halogenating reagent has a low boiling point, when the present invention is applied to a silicon material such as metallic silicon, only the reagent evaporates before the silicon is dissolved or vaporized, and the halogenation effect is reduced. Can not be obtained.

On the other hand, it has been reported that about 0.1% of freon was mixed in a part of the plasma forming gas (carrier gas) to suppress the formation of carbides [GKKirkbriht, Z. Li-Xing: Analys
t, 107617 (1982)], but analysis over a long period of time caused damage to the quartz sample introduction part and quartz plasma torch due to the continuous injection of fluorine, and adhesion of carbon to the tip of the torch, etc. It is not practical because it lowers the analysis accuracy.

[0009] Therefore, the present inventors have attempted to increase the sensitivity by increasing the vaporization efficiency by converting the sample into hydride or halide when inserting the sample into the plasma in the boron analysis (Japanese Patent Application No. 9-302767). issue). By the above-mentioned method, it became possible to increase the sensitivity of boron and analyze a trace amount of boron in the silicon material by a method with excellent accuracy, but it was difficult to improve the lower limit of quantification to sub-ppm or less.
It was necessary to study a more accurate method for analyzing trace amounts of boron for the following samples containing boron.

[0010]

SUMMARY OF THE INVENTION The present invention solves the above-mentioned problems of the prior art and removes trace amounts of phosphorus and boron from silicon materials such as high-purity silicon materials used for solar cells, semiconductors, and electronic materials. It is an object of the present invention to provide a highly sensitive and rapid method and apparatus for analyzing phosphorus and boron in a silicon material, which can be analyzed quickly with high accuracy.

[0011]

According to a first aspect of the present invention, a silicon material is directly inserted into a high-temperature plasma to excite and emit light. The emission intensity of phosphorus, the emission intensity of phosphorus background and the emission intensity of silicon are obtained. Simultaneously measure the three, the emission intensity ratio shown by the following formula (1) is determined, and the emission intensity of the above three is simultaneously measured using a silicon sample with a known phosphorus concentration, based on the following formula (1) Determining a calibration curve that is a correlation equation between the obtained emission intensity ratio and the phosphorus concentration, and determining a phosphorus concentration in the silicon material from the calibration curve and the emission intensity ratio of the silicon material described above. It is a sensitive and rapid method for the analysis of phosphorus in foods.

Light emission intensity ratio = (phosphorus light emission intensity−phosphorus background light emission intensity) / (silicon light emission intensity) (1) In the second invention, a silicon material is directly heated at a high temperature. The excitation light emission is inserted into the plasma of the above, the emission intensity of boron, the emission intensity of boron background and the emission intensity of silicon are simultaneously measured, and the emission intensity ratio shown by the following formula (2) is obtained. Using a silicon sample with a known boron concentration, the luminescence intensities of the above three were simultaneously measured, and a calibration curve which was a correlation equation between the luminescence intensity ratio obtained based on the following equation (2) and the boron concentration was obtained. A high-sensitivity rapid analysis method for boron in a silicon material, wherein a boron concentration in the silicon material is obtained from a line and an emission intensity ratio of the silicon material.

Emission intensity ratio = (Emission intensity of boron−Emission intensity of boron background) / (Emission intensity of silicon) (2) In the second aspect of the present invention, hydrogen, hydrogen, It is more preferable to add one or more selected from halogen gas, gaseous halide and steam.

According to a third aspect of the present invention, there is provided a plasma torch 3 having a light emitting portion 1 which emits light by high-temperature plasma, a sample insertion device 2 for directly inserting a sample into the light emitting portion 1, and light emission from the light emitting portion 1. For simultaneously measuring the three components of (a) the emission intensity of phosphorus, (b) the emission intensity of the background of phosphorus, and (c) the emission intensity of silicon, which are spectrally separated by the spectral unit 8. And the detectors 9a, 9b, and 9c of (a) and (b), the emission intensity of boron, the emission intensity of the background of boron, and the emission intensity of (c) silicon, which were spectrally separated by the spectral unit 8, were simultaneously measured. Detectors 9d, 9e, 9c for performing the measurement, and the emission intensities of the five persons obtained by the detectors 9a, 9b, 9c, 9d, 9e
(a), (b), (c), (d), (e) based on the data processing unit 5 having a function of calculating the emission intensity ratio represented by the following formulas (1) and (2)
A highly sensitive and rapid analyzer for phosphorus and boron in a silicon material, characterized by having:

Emission intensity ratio = (Emission intensity of phosphorus−Emission intensity of background of phosphorus) / (Emission intensity of silicon) (1) Emission intensity ratio = (Emission intensity of boron−Emission intensity of boron) (Emission intensity of background) / (Emission intensity of silicon) (2) In the third aspect of the present invention, hydrogen, halogen gas, gaseous halide and water vapor are contained in the plasma forming gas of the plasma torch 3. It is preferable to provide a gas introduction device for adding one or more kinds selected from the group consisting of:

[0016] Note that the plasma in the first aspect of the present invention to third invention described above, Ar generated by radio wave or microwave discharge, it is preferable to use a high-frequency plasma of He or N _2.

[0017]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in more detail. In the first aspect, the silicon material contained in the sample cup such as the graphite cup is directly inserted into the high-temperature plasma to excite and emit light, and the phosphor emission intensity, the phosphor background emission intensity and The emission intensity of silicon is measured simultaneously.

In the second invention, the silicon material housed in a sample cup such as a graphite cup is
It is directly inserted into a high-temperature plasma to excite and emit light, and simultaneously measures the emission intensity of boron, the emission intensity of background boron, and the emission intensity of silicon. In this case, preferably, in a plasma forming gas such as Ar for forming a high-temperature plasma, a hydrogen gas such as hydrogen, Cl _2, Br ₂ , or F ₂ to promote the vaporization of boron;
By adding one or more selected from a gaseous halide such as hydrogen chloride, hydrogen bromide and hydrogen fluoride and water vapor, the emission intensity of boron is increased, and higher sensitivity can be achieved.

As the luminescence analysis line of phosphorus, boron, and silicon (: measurement wavelength), any luminescence analysis line having sensitivity enough to obtain luminescence intensity corresponding to the concentration required for analysis is arbitrarily selected. However, as an emission analysis line with less interference of coexisting elements such as silicon, a wavelength such as PI 178.29 nm or PI 177.44 nm for phosphorus and a BI 182.64 nm or BI 249.7 nm for boron is preferable. .

Since silicon has a high content, an arbitrary wavelength can be used. However, it is better to use an atomic beam of, for example, SiI 251.6 nm, which exhibits a behavior similar to that of phosphorus or boron in plasma. (: Emission intensity ratio correction of silicon) at the time of being unaffected by the fluctuation of the apparatus, it is possible to perform more accurate analysis. It is necessary to select the wavelength of the backround as small as possible with the interference of silicon and other anticipated coexisting components, which may be set separately for phosphorus and boron, and for the measurement of phosphorus and boron. When the measurement wavelengths of phosphorus and boron having relatively close wavelengths are selected, the intensity measured at one background wavelength can be used as the background intensity.

For example, when PI 178.29 nm and BI 182.64 nm are used as measurement wavelengths, the background emission intensity can be measured at around 180 nm. For this reason,
It is also possible to use the detector 9b for the background emission intensity of phosphorus and the detector 9e for the background emission intensity of boron in the third aspect of the invention as a single unit.

Next, in the case of phosphorus analysis, the luminescence intensity ratio expressed by the following equation (1) is obtained from the luminescence intensity of phosphorus, background luminescence intensity of phosphor and luminescence intensity of silicon measured simultaneously. Hereinafter, the emission intensity ratio (also referred to as P-α _P / Si) is determined. Light emission intensity ratio _{(P-α P / Si)} = - The (phosphorus emission intensity emission intensity of the background phosphorus) / (emission intensity of silicon) ............... (1), if the analysis of boron, From the light emission intensity of boron, the light emission intensity of boron background and the light emission intensity of silicon measured at the same time, the light emission intensity ratio represented by the following formula (2) (hereinafter also referred to as light emission intensity ratio (B-β _B / Si) Write)
Ask for.

Emission intensity ratio (B-β _B / Si) = (Emission intensity of boron−Emission intensity of boron background) / (Emission intensity of silicon) (2) Silicon has a high content, The influence of the background emission intensity on the net emission intensity is quite small, so there is no need to perform silicon background correction in particular,
If the conditions of the measuring device allow, the emission analysis line of silicon (:
If a background wavelength that does not cause interference is set near (measurement wavelength) and the background intensity of the emission intensity of silicon is corrected using the measured intensity, the analysis accuracy can be further improved.

A calibration curve or a correlation curve, which is a correlation equation between the emission intensity ratio (P-α _P / Si) for phosphorus and silicon and the phosphorus concentration, prepared by a method similar to the above using a sample having known concentrations of phosphorus and boron. Emission intensity ratio for boron and silicon (B
−β _B / Si) and the boron concentration are converted into a phosphorus concentration (= phosphorus content) and a boron concentration (= boron content) in the sample using a calibration curve which is a correlation formula between the boron concentration and the boron concentration.

Next, FIG. 3 is a sectional view showing an example of a high-sensitivity and rapid analyzer for phosphorus and boron in a silicon material according to the present invention. In FIG. 3, reference numeral 1 denotes a light emitting unit that emits light by high-temperature plasma, 2 denotes a sample insertion device for directly inserting a sample into the light emitting unit 1, 3 denotes a plasma torch, 4 denotes a spectrometer,
A detector 5, a data processing unit 5, a plasma forming gas 6 such as Ar, 7 a condenser lens, 8 a spectroscopic unit using a diffraction grating,
9a, 9b, 9c, 9d, 9e are detectors using a photomultiplier tube, 12 is a sample cup, 13 is a lid for preventing carrier gas leakage, 14 is a shaft of the sample cup, 15 is a sample cup driving device, 16 Denotes a gas introduction device for introducing hydrogen, halogen gas, gaseous halide and water vapor, and 20 denotes an ICP (high frequency inductively coupled plasma).

In the present invention, a prism can be used as the light splitting unit 8 instead of the above-described diffraction grating, and the method of splitting light is not particularly limited. Further, in the present invention, as the detectors 9a, 9b, 9c, 9d, 9e, a CCD (: charge co
Upled device) It is also possible to use a detector, and the type of the detector is not particularly limited.

In the present invention, in order to realize the above-described analysis method, it is preferable to use an analyzer having the following configuration. (1): a plasma torch 2 having a light-emitting portion 1 that emits light by high-temperature plasma; as shown in FIG. 3, this device uses a halogen gas for halogenating boron to increase the sensitivity of boron. A gas introduction device 16 for adding at least one gas selected from gaseous halides, hydrogen for hydrogenating boron, and water vapor for generating oxides of boron to the plasma forming gas of the plasma torch 3 is provided. It is preferable to attach it.

(2): a sample insertion device 3 for directly inserting a sample into the light emitting section 1; (3): a spectroscopic detector 4;
A spectrometer and a detector for measuring the luminescence intensity of each of phosphorus, boron and silicon, the luminescence intensity of the background of phosphorus and the luminescence intensity of the background of boron.

(4): Data processing unit 5; correction of the background light emission intensity of phosphorus and the background light emission intensity of boron with respect to the emission intensity of phosphorus and the emission intensity of boron obtained by spectroscopy and detector 4, respectively. In addition to performing the correction, the sample evaporation amount correction based on the emission intensity of silicon (:
Data processing unit that performs silicon light emission intensity ratio correction).

The amount of evaporation of the sample is corrected based on the emission intensity of silicon by the above-described equations (1) and (2). When using a wavelength in the vacuum ultraviolet region of 200 nm or less as the measurement wavelength for phosphorus and boron, use a vacuum type or inert gas replacement type spectroscope as the spectroscope, and use MgF or the like in the light-transmitting parts such as the condenser lens. By using a material having a high transmittance at a wavelength in the vacuum ultraviolet region, measurement with higher sensitivity is possible.

According to the present invention described above, without being affected by the spectral interference of the silicon as the matrix and the background increase called white noise caused by inserting the sample cup into the plasma, the sub-pp
The lower limit of quantification has been extended to m or less, enabling high-precision analysis. In addition, in the boron analysis, when a sample is inserted into plasma, one or two or more kinds selected from a halogen gas, a gaseous halide, hydrogen, and water vapor are added to a plasma forming gas, so that boron is removed. The vaporization efficiency is increased, the luminescence intensity of boron is increased by a very simple method, and a more sensitive analysis of boron becomes possible.

[0032]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be specifically described below based on embodiments. (Example) Phosphorus and boron in a silicon material were analyzed using the analyzer of the present invention shown in FIG.

Ar was used as a plasma forming gas. The spectroscopy and detector 4 use a vacuum type, and the photomultiplier tubes 9a to 9e are PI
178.29nm, BI 182.64nm, 180 as backround.
The wavelength was set to 00 nm and the SiI to 261.6 nm. The condenser lens 7
The one made of MgF was used. In addition, as a gaseous halide introduction device in the gas introduction device 16 for introducing hydrogen, halogen gas, gaseous halide, and steam, hydrochloric acid (1 + 1) is put into a bubbling device having a temperature control function, and the temperature is kept at 5 ° C. The carrier gas was passed at 0.8 l / min and introduced into the plasma.

The sample cup 12 was made of hollow graphite having a volume of 50 μl, and was connected to a graphite shaft having a cross-sectional diameter of 1 mm. The sample was used in an amount of 20 mg, and was directly inserted into the plasma from below the plasma torch 3 with the lower part opened, with the plasma turned on. The emission intensity generated at this time is determined by the photomultiplier tubes 9a to 9e.
And transfers it to the data processing unit 5.

The data processing unit 5 calculates the integrated intensity of each luminescent signal, and calculates the integrated intensity of the luminescent signal of phosphorus, the luminescent intensity of boron, the luminescent intensity of the background of phosphorus, the luminescent intensity of the background of boron, and the luminescent intensity of silicon. The following formula
Based on (1) and (2), the emission intensity ratio (P-α _P / Si),
The emission intensity ratio (B-β _B / Si) is calculated. Emission intensity ratio (P-α _P / Si) = (Emission intensity of phosphorus−Emission intensity of background of phosphorus) / (Emission intensity of silicon)... (1) Emission intensity ratio (B−β _B / Si) = (Emission intensity of boron−Emission intensity of boron background) / (Emission intensity of silicon) (2) Next, the respective emission intensity ratios described above and the phosphorus concentration were determined in advance by wet analysis. And a calibration curve which is a correlation equation between the luminescence intensity ratio (P-α _P / Si) and the phosphorus concentration of phosphorus prepared by a method similar to the above using a silicon sample having a known boron concentration and the luminescence of boron. The phosphorus concentration (: P content) and the boron concentration (: B content) in the silicon material are converted from a calibration curve which is a correlation equation between the intensity ratio (B-β _B / Si) and the boron concentration.

FIG. 1 shows a calibration curve of phosphorus obtained by the method and apparatus of the present invention, and FIG. 2 shows a calibration curve of boron obtained by the method and apparatus of the present invention. In preparing the calibration curve, Ar containing hydrogen chloride and moisture was introduced into the plasma torch 3 from the gas introduction apparatus shown in FIG. Phosphorus integrated the luminescent signal from 5 seconds to 15 seconds after inserting the sample into the plasma, and boron integrated the luminescent signal from 5 seconds to 25 seconds.

In order to reduce the influence of segregation in the sample, each sample was analyzed three times and the average value was used. By the background correction, the signal / background ratio is greatly improved, and the linearity of the calibration curve is good even in a trace area where the phosphorus content and the boron content are 0.1 to 0.2 wt-ppm or less. It is found to be useful as a rapid and sensitive analytical method for phosphorus and boron in the solution.

Next, the results of quantifying phosphorus and boron in actual samples using the calibration curves shown in FIGS. 1 and 2 by the method, apparatus and analysis method of the present invention in the same manner as when the calibration curves were prepared are shown in Table 1. And Table 2. As shown in Table 1, the present invention makes it possible to quantify a sample having a phosphorus content of 0.07 wt-ppm with a standard deviation σ = 0.005 wt-ppm.

As shown in Table 2, a sample having a boron content: 0.17 wt-ppm level had a standard deviation σ = 0.021 wt-pp.
m. Furthermore, according to the analysis method of the present invention described above, according to the analyzer, the sample preparation is cut out to accommodate the sample to be analyzed in the sample cup,
It only needs to be crushed, and can be performed easily and in a short time.

In addition, the time required from the insertion of the sample into the high-temperature plasma to the calculation of the emission intensity ratio is 1 to 3 minutes per sample, so that analysis can be performed very quickly.

[0041]

[Table 1]

[0042]

[Table 2]

(Comparative Example) Using the analytical apparatus of the present invention shown in FIG. 3 described above, using a silicon sample having a known phosphorus concentration and boron concentration, a calibration curve and a correlation equation representing the correlation between the emission intensity and the phosphorus concentration of phosphorus. A calibration curve, which is a correlation equation between the emission intensity of boron and the boron concentration, was created.

The obtained calibration curves are shown in FIGS. The unit au of the light emission intensity on the vertical axis in FIGS. 4 and 5 is an arbitrary unit. As is clear from comparison of FIGS. 4 and 5 with FIGS. 1 and 2, the calibration curves (FIGS. 4 and 5) of the emission intensity, the phosphorus concentration and the boron concentration show that the P content ratio and the B content ratio are 0.4. The dispersion is large below wt-ppm, and it is not possible to accurately quantify trace amounts of phosphorus and boron as shown in FIGS. 1 and 2 and Tables 1 and 2 using these calibration curves.

Tables 3 and 4 show the results of quantitative analysis of a silicon material having a high phosphorus and boron content by the following method. [Phosphorus content:] (a) Direct method; Calibration curve which is a correlation equation between phosphorous emission intensity and phosphorous concentration for a silicon sample having a known phosphorous concentration,
The phosphorus content was determined from the emission intensity of phosphorus in the silicon material.

That is, in the present direct method, the background correction of phosphorus and the emission intensity ratio correction of silicon are not performed. (b) Silicon emission intensity ratio method: For a silicon sample with a known phosphorus concentration, the emission intensity ratio (P /
A calibration curve, which is a correlation equation between Si) and the phosphorus concentration, was determined, and the phosphorus content was determined from the obtained calibration curve and the emission intensity ratio (P / Si) of the silicon material represented by the following equation (3).

Emission intensity ratio (P / Si) = (Emission intensity of phosphorus) / (Emission intensity of silicon) (3) That is, in the above emission intensity ratio (P / Si) method, the background of phosphorus No correction was made. [Boron content:] Emission intensity ratio method of silicon: For a silicon sample having a known boron concentration, an emission intensity ratio (B / S
A calibration curve, which is a correlation equation between i) and the boron concentration, was determined, and the boron content was determined from the obtained calibration curve and the emission intensity ratio (B / Si) of the silicon material represented by the following equation (4).

Emission intensity ratio (B / Si) = (Emission intensity of boron) / (Emission intensity of silicon) (4) That is, in the above emission intensity ratio (B / Si) method, the background correction of boron is performed. Has not gone. In the case of boron, when the emission intensity ratio correction of silicon represented by the above formula (4) was not performed, the analysis values had large variations, and accurate quantification of boron was impossible.

As is clear from the comparison between Tables 1 and 3 and the comparison between Tables 2 and 4, in addition to the luminescence intensity of phosphorus and luminescence of boron, the luminescence intensity of the background of phosphorus and boron, According to the analysis method and the analyzer of the present invention using both the emission intensity of silicon, the sub-pp
It can be seen that the lower limit of quantification can be improved to m or less, and that trace amounts of phosphorus and boron in sub-ppm or less can be analyzed by a method with excellent accuracy.

[0050]

[Table 3]

[0051]

[Table 4]

[0052]

As described above, according to the present invention, it is possible to analyze a trace amount of phosphorus and a trace amount of boron at a sub-ppm level or less in high-purity silicon by a simple method with high accuracy and extremely quickness. became. In other words, trace analysis of trace amounts of phosphorus and boron in high-purity silicon, which has been difficult and traceable until now, can now be performed easily and extremely quickly. Analysis and reaction control of the silicon manufacturing process used for semiconductor materials and solar cells can be performed accurately and quickly, and significant effects are expected in terms of improving product quality and stable production.

[Brief description of the drawings]

FIG. 1 is a graph showing an example of a calibration curve of phosphorus according to the present invention.

FIG. 2 is a graph showing an example of a calibration curve of boron according to the present invention.

FIG. 3 is a cross-sectional view showing an example of a high-sensitivity rapid analysis apparatus for phosphorus and boron in a silicon material according to the present invention.

FIG. 4 is a graph showing a calibration curve of phosphorus.

FIG. 5 is a graph showing a calibration curve of boron.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Light-emitting part 2 Sample insertion apparatus for directly inserting a sample into a light-emitting part 3 Plasma torch 4 Spectroscopy and detector 5 Data processing part 6 Plasma forming gas 7 Condensing lens 8 Spectroscopic parts 9a, 9b, 9c, 9d, 9e Detector 12 Sample cup 13 Carrier gas leakage prevention lid 14 Sample cup shaft 15 Sample cup drive 16 Gas introduction device 20 ICP (High frequency inductively coupled plasma)

Claims (3)

[Claims] 1. A silicon material is directly inserted into a high-temperature plasma to excite and emit light, and phosphor emission intensity, phosphor background emission intensity and silicon emission intensity are simultaneously measured, and the following equation is obtained. The emission intensity ratio shown in (1) is determined, and the emission intensity ratio and the phosphorus concentration obtained based on the following formula (1) by simultaneously measuring the emission intensity of the above three members using a silicon sample with a known phosphorus concentration. A high-sensitivity rapid analysis method for phosphorus in a silicon material, comprising: obtaining a calibration curve which is a correlation formula of the following, and obtaining a phosphorus concentration in the silicon material from the calibration curve and the emission intensity ratio of the silicon material. Note: Emission intensity ratio = (phosphorus emission intensity-phosphor background emission intensity) / (silicon emission intensity) (1) 2. A method in which a silicon material is directly inserted into a high-temperature plasma to emit excited light, and the three values of luminescence intensity of boron, luminescence intensity of boron background and luminescence intensity of silicon are measured at the same time. While obtaining the emission intensity ratio shown in (2), the emission intensity ratio and the boron concentration obtained based on the following equation (2) by simultaneously measuring the emission intensity of the above three using a silicon sample with a known boron concentration and A high-sensitivity rapid analysis method for boron in a silicon material, comprising: obtaining a calibration curve which is a correlation formula of the following, and obtaining a boron concentration in the silicon material from the calibration curve and the emission intensity ratio of the silicon material. Note: Emission intensity ratio = (Emission intensity of boron-Emission intensity of background of boron) / (Emission intensity of silicon) ... (2) 3. A light emitting section that emits light by high-temperature plasma.
(1) a plasma torch (3), and the light emitting section (1)
A sample insertion device (2) for directly inserting a sample into the sample, a spectroscopy unit (8) for separating the light emitted from the light emitting unit (1), and (a) phosphorous separated by the spectroscopy unit (8). The detectors (9a, 9b, 9c) for simultaneously measuring the three components of the emission intensity, (b) the background emission intensity of phosphorus, and (c) the emission intensity of silicon, are separated by the spectral unit (8). (D) emission intensity of boron, (e)
A detector (9d, 9) for simultaneously measuring the background emission intensity of boron and the emission intensity of (c) silicon.
e, 9c) and the emission intensity (a), (b), (c), (d), (e) of the five persons obtained by the detector (9a, 9b, 9c, 9d, 9e). Based on the following formula
A highly sensitive and rapid analyzer for phosphorus and boron in a silicon material, comprising a data processing section (5) having a function of calculating the emission intensity ratio shown in (1) and (2). Note: Emission intensity ratio = (Emission intensity of phosphorus-Emission intensity of background of phosphorus) / (Emission intensity of silicon) ............ (1) Emission intensity ratio = (Emission intensity of boron-Background of boron) Emission intensity) / (silicon emission intensity) ............ (2)