Chlorosilane impurity analysis and sample preparation device

Abstract

The utility model provides a chlorosilane impurity analysis and sample preparation device, and aims to solve the problems of influence of pollutants in an analysis and sample preparation device before detection of chlorosilane impurities on detection precision and low efficiency caused by long sample preparation time in the prior art. The device comprises a base plate and a protective cover arranged above the base plate, and the protective cover is provided with an air inlet and a plurality of air outlets; the air inlet is communicated with a two-way valve, and the other end of the two-way valve is connected with an FEP air inlet pipe; the plurality of air outlets are arranged in an array from top to bottom, and latex hoses are connected to the air outlets. A plurality of exhaust holes are formed in the protective cover, so that gas in the cover body can be exhausted in time, cross contamination in the sample preparation process in the cover body is effectively ensured, the protective cover is prevented from being polluted, the sample preparation time is effectively prolonged, the PFA two-way valve is arranged at the air inlet of the cover body, direct connection with a latex tube is avoided, and the sample preparation efficiency is improved. High-purity air inlet pollution is caused, and the detection precision is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of polysilicon production, in particular to a chlorosilane impurity analysis and sample preparation device. Background Art

[0002] In the field of polysilicon production, chlorosilane is one of the key raw materials. Its impurity content directly affects product quality. Therefore, the accurate determination of the chlorosilane impurity content is very important. The chlorosilane impurity content includes metal impurities and boron and phosphorus elements. At present, the chlorosilane analysis and sample preparation device in the industry uses a quartz protective cover to protect and dry. It is designed with an air inlet and an exhaust port. A latex hose is connected to the quartz cover air inlet to pass high-purity carrier gas. The other side is the exhaust port to discharge the carrier gas and chlorosilane vaporized gas. When testing, the sample in the sample preparation vessel in the quartz protective cover vaporizes and evaporates, and the metal impurities remain in the sample preparation vessel. The metal impurities detected in the sample preparation vessel are the metal impurity content in the sample.

[0003] The current quartz protective cover is equipped with a single exhaust port, which has the following problems: First, a portion of the carrier gas and chlorosilane vaporized gas will accumulate inside the quartz cover and cannot be discharged in time, resulting in a long sampling time and low efficiency; second, in addition to the carrier gas, the gas accumulated inside the quartz cover also includes a large amount of chlorosilane vaporized gas, which has a relatively high impurity content, which will cause cross-contamination of the sample inside the quartz cover; third, chlorosilane gas will corrode and deposit on the inner surface of the quartz cover, causing the inner surface of the quartz cover to be covered with silica, which cannot be cleaned. Over time, there is a risk of internal silica falling off and causing sample contamination; fourth, high-purity carrier gas needs to be connected through a latex hose to enter the quartz protective cover. The latex hose itself has a high impurity content and is not resistant to chlorosilane corrosion, which will contaminate the high-purity carrier gas, thereby causing sample contamination.

[0004] Therefore, it is of great significance to study a chlorosilane impurity analysis sample preparation device with short sample preparation time, high detection accuracy and avoidance of cross contamination in the protective cover. Utility Model Content

[0005] The purpose of this utility model is to solve the problems in the prior art of sample preparation devices for analyzing chlorosilane impurities, such as the quartz cover used in the cover easily causing sample contamination inside the cover, affecting detection accuracy, and the long sample preparation time resulting in low efficiency. By improving the structure of the protective cover, the utility model effectively prevents cross contamination inside the cover during the sample preparation process, prevents contamination of the protective cover, and effectively shortens the sample preparation time.

[0006] In order to solve the above technical problems, the present invention adopts the following technical solutions:

[0007] A sample preparation device for chlorosilane impurity analysis comprises a pad, a sample preparation vessel on the pad, and a protective cover arranged above the sample preparation vessel, wherein the protective cover is provided with an air inlet and a plurality of air outlets symmetrically arranged along its axis; the air inlet is connected to a two-way valve, the other end of the two-way valve is connected to an FEP air inlet pipe, and high-purity carrier gas enters the protective cover from the air inlet through the FEP air inlet pipe and the two-way valve; the plurality of air outlets are arranged in an array from top to bottom, and are all connected to latex hoses, so that a gas mixed with chlorosilane vaporized gas and carrier gas is discharged through the latex hoses.

[0008] As the preferred technical solution:

[0009] In the above-mentioned chlorosilane impurity analysis and sample preparation device, the air inlet is set at a height twice the height of the sample preparation vessel from the pad. The purpose of setting the air inlet at this position is to ensure the accuracy and work efficiency of sample preparation. If it is higher than this position, the volatile gas of the chlorosilane sample needs to be gathered at the top before being discharged, affecting the volatile efficiency of the chlorosilane sample. If it is lower than this position, the air inlet will be very close to the sample preparation vessel, and the volatilized part of the sample will be carried out by the high-purity carrier gas, and at the same time, some metal impurities in the sample will also be carried out, resulting in deviation in the detection results.

[0010] In the above-mentioned chlorosilane impurity analysis and sample preparation device, the positions at which the multiple air outlets are arranged are above the height of the sample preparation vessel, and one of the air outlets is symmetrical with the air inlet, and the remaining air outlets are evenly distributed along the air outlet. The purpose of arranging the multiple air outlets at this position is to arrange the multiple air outlets at a position near the height of the sample preparation vessel in the protective cover, symmetrical with the air inlet, so that the volatile gas of the chlorosilane sample can be quickly discharged.

[0011] In the above-mentioned chlorosilane impurity analysis and sample preparation device, the number of the plurality of air outlets is at least 3, and the preferred number is 3, 4 or 5. The number of air outlets in the utility model is related to the height of the protective cover, and the height of the protective cover depends on the number of samples placed in the protective cover and the height of the sample preparation vessel. Generally, the number of samples prepared in the same protective cover does not exceed 6.

[0012] As described above, in a chlorosilane impurity analysis and sample preparation device, the other end of the FEP air inlet pipe is connected to the air supply port of the argon gas device, which is used to introduce high-purity argon gas as a carrier gas into the protective cover. The utility model adopts an FEP air inlet pipe, which is different from the prior art that adopts a latex hose, in order to avoid the latex hose connection from contaminating the high-purity carrier gas.

[0013] In the above-mentioned chlorosilane impurity analysis and sample preparation device, the plurality of gas outlets are connected to the latex hoses to discharge the collected gas through a fume hood.

[0014] In the above-mentioned chlorosilane impurity analysis sample preparation device, the material of the protective cover and the backing plate is PTFE, PFA or FEP.

[0015] In the above-mentioned chlorosilane impurity analysis and sample preparation device, the two-way valve is a PFA two-way valve.

[0016] In the above-mentioned chlorosilane impurity analysis sample preparation device, a beaker made of FEP, PFA or PTFE is placed on the stage for placing the chlorosilane sample to be tested for impurities.

[0017] Compared with the prior art, the beneficial effects of the present invention are:

[0018] 1. The utility model is a chlorosilane impurity analysis and sample preparation device. By replacing the existing quartz protective cover with PTFE, PFA or FEP material, the corrosion of the protective cover by chlorosilane gas can be avoided, ensuring that no new impurities are introduced during the sample preparation process.

[0019] 2. The utility model is a chlorosilane impurity analysis and sample preparation device. By using multiple air outlets on the protective cover, the carrier gas and chlorosilane vaporized gas in the cover body can be discharged in time, thereby avoiding the accumulation of high-purity carrier gas and chlorosilane vaporized gas in the protective cover, which will cause cross contamination in the sample preparation process.

[0020] 3. The utility model is a chlorosilane impurity analysis and sample preparation device. By using multiple air outlets on the protective cover, the carrier gas and chlorosilane vaporized gas in the cover can be discharged in time, thereby improving the volatilization efficiency of the chlorosilane sample and saving sample preparation time.

[0021] 4. The utility model provides a chlorosilane impurity analysis and sample preparation device, which can ensure that the high-purity carrier gas is not contaminated during the process of being introduced into the protective cover by arranging a two-way valve at the air inlet on the protective cover. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0023] Figure 1 This is a schematic structural diagram of a chlorosilane impurity analysis and sample preparation device according to the present invention;

[0024] Figure 2 This is a structural diagram of the device of the utility model after connecting the argon device and the fume hood.

[0025] Reference numerals:

[0026] 1-Pad; 2-Sample preparation vessel; 3-Protective cover; 4-Air inlet; 5-Air outlet; 6-Two-way valve; 7-FEP air inlet pipe; 8-Latex hose; 9-Argon device; 10-Fume hood. DETAILED DESCRIPTION

[0027] Hereinafter, only certain exemplary embodiments are briefly described. As will be appreciated by those skilled in the art, the described embodiments may be modified in various ways without departing from the spirit or scope of the present invention. Therefore, the drawings and description are to be regarded as illustrative in nature and not restrictive.

[0028] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, or are the orientations or positional relationships in which the products of the present invention are conventionally placed when in use, or are the orientations or positional relationships conventionally understood by those skilled in the art. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation to the present invention.

[0029] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of the technical features being referred to. Thus, a feature specified as "first" or "second" may explicitly or implicitly include one or more of such features. In the description of this utility model, "plurality" means two or more, unless otherwise specifically defined.

[0030] In this utility model, unless otherwise expressly specified or limited, the terms "installed," "connected," "connect," "fixed," etc. should be understood in a broad sense. For example, they can refer to fixed connection, detachable connection, or integration; mechanical connection, electrical connection, or communication; direct connection or indirect connection through an intermediate medium; internal communication between two components or interaction between two components. For those skilled in the art, the specific meanings of the above terms in this utility model can be understood according to specific circumstances.

[0031] In the present invention, unless otherwise expressly specified or limited, a first feature being "above" or "below" a second feature may include the first and second features being in direct contact, or may include the first and second features being in contact not directly but through another feature between them. Moreover, a first feature being "above," "above," and "above" a second feature may include the first feature being directly above or obliquely above the second feature, or may simply mean that the first feature is higher in level than the second feature. A first feature being "below," "below," and "below" a second feature may include the first feature being directly below or obliquely below the second feature, or may simply mean that the first feature is lower in level than the second feature.

[0032] The disclosure below provides many different embodiments or examples for realizing different structures of the present invention. In order to simplify the disclosure of the present invention, the components and settings of specific examples are described below. Of course, they are merely examples and are not intended to limit the present invention. In addition, the present invention may repeat reference numbers and / or reference letters in different examples. Such repetition is for the purpose of simplicity and clarity and does not in itself indicate the relationship between the various embodiments and / or settings discussed. In addition, the present invention provides examples of various specific processes and materials, but a person of ordinary skill in the art will recognize the application of other processes and / or the use of other materials.

[0033] The embodiments of the present invention are described in detail below with reference to the accompanying drawings.

[0034] The present invention provides a device for analyzing and preparing chlorosilane impurities. Figure 1 As shown, it includes a pad 1, a sample preparation vessel 2 on the pad, and a protective cover 3 arranged above the sample preparation vessel 2. The protective cover 3 is provided with an air inlet 4 and at least three air outlets 5 symmetrically arranged along its axis. This embodiment preferably adopts a design with four air outlets, but it can also be selected to be 3 or 5, or more according to the actual number of sample preparations or the height of the sample preparation vessel. This embodiment is not described in detail here; the position where the air inlet 4 is set is twice the height of the sample preparation vessel, that is, the height of the sample preparation vessel is h, and the distance between the center of the air inlet 4 and the top of the sample preparation vessel is h, that is, the distance from the pad is 2h.

[0035] The air inlet 4 is connected to a two-way valve 6 , the other end of which is connected to an FEP air inlet pipe 7 . High-purity carrier gas passes through the FEP air inlet pipe 7 and the two-way valve 6 in sequence and enters the protective cover 3 from the air inlet 4 .

[0036] The four air outlets 5 are arranged in an array from top to bottom, and are all located above the height of the sample preparation vessel 2, and one of the air outlets 5 is symmetrical to the air inlet 4, as shown in FIG. Figure 1As shown in FIG, the second gas outlet from top to bottom is symmetrically arranged in the same horizontal plane as the gas inlet 4, and the remaining three gas outlets are evenly distributed along the second gas outlet. The four gas outlets 5 are all connected to a latex hose 8, through which the gas mixed with the vaporized chlorosilane gas and the carrier gas is discharged.

[0037] Preferably, the protective cover and the backing plate are made of PTFE, PFA or FEP.

[0038] Preferably, the two-way valve is a PFA two-way valve.

[0039] Preferably, the sample preparation vessel is a beaker made of FEP, PFA or PTFE, which is used to place the chlorosilane sample to be tested for impurities.

[0040] The other end of the FEP air inlet pipe 7 in the chlorosilane impurity analysis and sample preparation device of the present invention is connected to the air supply port of the argon gas device 9, as shown in FIG. Figure 2 As shown, it is used to connect high-purity argon gas as a carrier gas into the protective cover 3. The four gas outlets 5 are connected to the latex hose 8 and are also connected to the fume hood 10. The mixed gas of chlorosilane vaporized gas and argon carrier gas volatilized from the sample preparation vessel in the protective cover is discharged through the fume hood 10.

[0041] The method for preparing samples and performing chlorosilane impurity analysis using the chlorosilane impurity analysis sample preparation device of the present invention is as follows:

[0042] (1) Open the two-way valve on the air inlet of the protective cover, open the valve of the argon device, and let the argon gas flow into the FEP air inlet pipe and the two-way valve through the air supply port of the argon device and finally into the protective cover. Adjust the carrier gas flow rate to the standard value by adjusting the opening of the control valve;

[0043] (2) Replace the gas inside the protective cover for 10 minutes to make the protective cover in an argon environment;

[0044] (3) Place the chlorosilane sample to be tested for impurities in a sample preparation vessel and place it on a PTFE pad. Then place a protective cover on top of the sample preparation vessel to ensure that the protective cover and the PTFE pad are sealed.

[0045] (4) The high-purity carrier gas entering the protective cover is mixed with the chlorosilane vaporized gas emitted by the sample in the sample preparation vessel, and then discharged from the four gas outlets in the protective cover under the action of a certain pressure difference;

[0046] (5) The exhaust gas discharged from the four air outlets of the protective cover passes through the latex hose connected to it, and then is discharged to other equipment for purification through the fume hood;

[0047] (6) As high-purity carrier gas is continuously introduced into the protective cover, it is continuously mixed with the chlorosilane vaporized gas and continuously discharged from the four gas outlets until the chlorosilane vaporized gas in the sample is completely volatilized. The argon device and the fume hood are turned off, the protective cover is opened, and the sample preparation vessel is taken out. An acid solution of the same mass as the chlorosilane sample is used to dissolve the metal impurities in the vessel, and the metal impurities remaining in the vessel are sent to the detection equipment for detection and results are obtained.

[0048] The device of the utility model effectively ensures cross contamination in the cover during the sample preparation process by improving the structure of the protective cover, avoids the protective cover from being contaminated, and effectively improves the sample preparation time.

Claims

1. A sample preparation device for chlorosilane impurity analysis, comprising a pad, a sample preparation vessel on the pad, and a protective cover arranged above the sample preparation vessel, characterized in that: The protective cover is provided with an air inlet and a plurality of air outlets symmetrically arranged along its axis; the air inlet is connected to a two-way valve, the other end of the two-way valve is connected to the FEP air inlet pipe, and high-purity carrier gas enters the protective cover from the air inlet through the FEP air inlet pipe and the two-way valve in sequence; the plurality of air outlets are arranged in an array from top to bottom, and the plurality of air outlets are all connected to a latex hose, and the gas mixed with chlorosilane vaporized gas and carrier gas is discharged through the latex hose.

2. A chlorosilane impurity analysis sample preparation device according to claim 1, characterized in that: The air inlet is arranged at a height from the pad that is twice the height of the sample preparation vessel.

3. A chlorosilane impurity analysis sample preparation device according to claim 1, characterized in that: The positions where the plurality of air outlets are arranged are located above the height of the sample preparation vessel, and one of the air outlets is symmetrical to the air inlet, and the remaining air outlets are evenly distributed along the air outlet.

4. A chlorosilane impurity analysis sample preparation device according to claim 1, characterized in that: The number of the plurality of air outlets is at least 3.

5. A chlorosilane impurity analysis sample preparation device according to claim 1, characterized in that: The other end of the FEP air inlet pipe is connected to the air supply port of the argon gas device, so as to introduce high-purity argon gas as a carrier gas into the protective cover.

6. A chlorosilane impurity analysis sample preparation device according to claim 1, characterized in that: The plurality of gas outlets are connected to the latex hoses to discharge the collected gas through a fume hood.

7. A chlorosilane impurity analysis sample preparation device according to claim 1, characterized in that: The material of the protective cover and the backing plate is PTFE, PFA or FEP.

8. A chlorosilane impurity analysis sample preparation device according to claim 1, characterized in that: The two-way valve is a PFA two-way valve.

9. A chlorosilane impurity analysis sample preparation device according to claim 1, characterized in that: The sample preparation vessel is a beaker made of FEP, PFA or PTFE, and is used for placing chlorosilane samples to be tested for impurities.

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