CN217612998U

CN217612998U - Purification device of high-purity boron trichloride

Info

Publication number: CN217612998U
Application number: CN202221951760.7U
Authority: CN
Inventors: 刘璧; 许进荣; 鲍坚仁; 徐学强
Original assignee: Apk Shanghai Gas Co ltd
Current assignee: Apk Shanghai Gas Co ltd
Priority date: 2022-07-27
Filing date: 2022-07-27
Publication date: 2022-10-21
Anticipated expiration: 2032-07-27

Abstract

The invention discloses a purification device of high-purity boron trichloride, which comprises a raw material tank, a first rectifying tower, a second rectifying tower and a finished product tank, wherein the raw material tank is connected with the first rectifying tower through a pipeline; the first rectifying tower is provided with a liquid phase inlet and a gas phase outlet, and the liquid phase inlet is connected with the raw material tank through a pipeline; the second rectifying tower is provided with a gas phase inlet and a liquid phase outlet, the gas phase inlet is connected with the gas phase outlet through a pipeline, and the liquid phase outlet is connected with the finished product tank through a pipeline. The purification device comprises the raw material tank, the two rectifying towers and the finished product tank, has simple structure and simple process, has high operability in actual production, can obtain high-purity boron trichloride, and has good purification effect; meanwhile, the double rectifying towers have low energy consumption in operation, thereby effectively saving resources and reducing the purification cost.

Description

Purification device of high-purity boron trichloride

Technical Field

The invention relates to the technical field of material purification, in particular to a purification device of high-purity boron trichloride.

Background

In the field of semiconductor chips, boron trichloride (BCl 3) is a key raw material, and since the percentage of chlorine is as high as 3/4, and chlorine is very corrosive, it is widely used as an etching gas in etching process steps in chip manufacturing processes, such as etching metal electrode layers, and etching alumina in patterned sapphire substrates, where alumina is usually very stable in chemical properties and is not easy to etch.

With the continuous reduction of the chip size, the condition control of the chip process is more and more precise, higher requirements are also put on the purity of boron trichloride, and the upper limit of the impurity content in the boron trichloride is more and more strict. The controllability of the chip process can be ensured only by using high-purity boron trichloride, namely, the purity of the boron trichloride is required to reach more than 6N. The most critical point for achieving sufficient purity of boron trichloride is to remove the most harmful and difficult impurities.

At present, in the prior art, a boron trichloride purification device is complex in structure and complex in process flow.

Disclosure of Invention

The invention aims to provide a purification device of high-purity boron trichloride, which is simple in structure and simple in process.

In order to achieve the purpose of the invention, the technical scheme adopted by the invention is as follows: a purification device of high-purity boron trichloride comprises a raw material tank, a first rectifying tower, a second rectifying tower and a finished product tank; the first rectifying tower is provided with a liquid phase inlet and a gas phase outlet, and the liquid phase inlet is connected with the raw material tank through a pipeline; the second rectifying tower is provided with a gas phase inlet and a liquid phase outlet, the gas phase inlet is connected with the gas phase outlet through a pipeline, and the liquid phase outlet is connected with the finished product tank through a pipeline.

Further, a filter and a flowmeter are arranged on a pipeline connecting the liquid phase inlet and the raw material tank.

Furthermore, a regulating valve is arranged on a pipeline connecting the gas phase inlet and the gas phase outlet.

Further, the first rectifying tower comprises a tower kettle, a tower body, a condenser and a reboiler, the tower kettle, the tower body and the condenser are sequentially connected from bottom to top, and the reboiler is connected with the tower kettle through a pipeline; the tower body is internally provided with tower plates, and the number of the tower plates is 10-100.

Further, the second rectifying tower comprises a tower kettle, a tower body, a condenser and a reboiler, the tower kettle, the tower body and the condenser are sequentially connected from bottom to top, and the reboiler is connected with the tower kettle through a pipeline; and tower plates are arranged in the tower body, and the number of the tower plates is 10-200.

Further, the first rectifying tower and the second rectifying tower are packed towers.

Further, the raw material tank and the finished product tank are steel cylinders.

Due to the application of the technical scheme, compared with the prior art, the invention has the following advantages:

the purification device comprises the raw material tank, the two rectifying towers and the finished product tank, has simple structure and simple process, is high in operability in actual production, can obtain high-purity boron trichloride, and has good purification effect; meanwhile, the double rectifying towers have low energy consumption in operation, thereby effectively saving resources and reducing the purification cost.

Drawings

FIG. 1 is a schematic view showing the overall connection of a purification apparatus of high purity boron trichloride according to the present invention;

fig. 2 is a schematic view of the structure of a first rectification column 2 of the present invention;

fig. 3 is a schematic structural view of second rectifying column 3 of the present invention;

FIG. 4 is a flow chart of the method for purifying high-purity boron trichloride according to the present invention.

Detailed Description

In order that the above objects, features and advantages of the present invention can be more clearly understood, the present invention will be further described in detail with reference to the accompanying drawings and the detailed description, wherein the drawings are simplified schematic drawings and only the basic structure of the present invention is illustrated schematically, so that only the structure related to the present invention is shown, and it is to be noted that the embodiments and features of the embodiments in the present application can be combined with each other without conflict.

In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present invention, but the present invention may be practiced in other ways than those specifically described herein, and therefore the scope of the present invention is not limited by the specific embodiments disclosed below.

Referring to fig. 1 to 3, a purification apparatus of high purity boron trichloride includes a raw material tank 1, a first rectifying tower 2, a second rectifying tower 3 and a finished product tank 4.

The raw material tank 1 is used for storing raw material, i.e., low-purity boron trichloride. The raw material tank 1 is connected with the first rectifying tower 2 through a pipeline, a filter 5 and a flowmeter are installed on the pipeline between the raw material tank 1 and the first rectifying tower 2, and the filter 5 is used for filtering out particles in boron trichloride.

The first rectifying tower 2 comprises a tower kettle 20, a tower body 21, a condenser 22 and a reboiler 23, wherein the tower kettle 20, the tower body 21 and the condenser 22 are sequentially connected from bottom to top, and the reboiler 23 is connected with the tower kettle 20 through a pipeline. The reboiler 23 is provided with a hot fluid inlet 231 and a hot fluid outlet 230. The tower body 21 is internally provided with trays, in the invention, the number of the trays 21 of the first rectifying tower 2 is 10-100, and the reflux ratio is 3-100. The tower body 21 is provided with a liquid phase inlet 210, and the low-purity boron trichloride enters the first rectifying tower 2 from the liquid phase inlet 210. The condenser 22 is provided with a cold fluid inlet 221, a cold fluid outlet 220 and a gas phase outlet 222, the gas phase outlet 222 is located at the top of the condenser 22, the gas phase outlet 222 is connected with the second rectifying tower 3 through a pipeline, and boron trichloride distilled by the first rectifying tower 2 flows out of the first rectifying tower 2 from the gas phase outlet and flows into the second rectifying tower 3.

The second rectifying tower 3 comprises a condenser 33, a tower body 32, a tower kettle 31 and a reboiler 34, wherein the condenser 33, the tower body 32 and the tower kettle 31 are sequentially connected from top to bottom. The condenser 33 is provided with a cold fluid inlet 332 and a cold fluid outlet 331. The tower body 32 is internally provided with trays, in the invention, the number of the trays of the second rectifying tower 3 is 10-200, and the reflux ratio is 10-1000. The tower body 32 is provided with a gas phase inlet 320, the gas phase inlet 320 is connected with the gas phase outlet 222 of the first rectifying tower 2 through a pipeline, and a regulating valve 6 is arranged on a connecting pipeline between the gas phase outlet 222 and the gas phase inlet 320. The tower bottom 31 is provided with a liquid phase outlet 310, and the liquid phase outlet 310 is connected with the finished product tank 4 through a pipeline. The reboiler 34 is connected with the tower bottom 31 through a pipeline, and the reboiler 34 is provided with a hot fluid inlet 341 and a hot fluid outlet 340.

Preferably, first rectification column 2 and second rectification column 3 are packed columns.

And the finished product tank 4 is used for storing the purified boron trichloride.

Preferably, the raw material tank 1 and the finished product tank 4 are steel cylinders.

Referring to fig. 4, based on the purification apparatus of high-purity boron trichloride, the invention provides a purification method of boron trichloride, which comprises the following steps:

filtering low-purity boron trichloride by using a filter screen, and then filling the boron trichloride into a raw material tank 1;

pressing boron trichloride into a first rectifying tower 2, distilling the boron trichloride in the first rectifying tower 2, and removing heavy components in the boron trichloride;

and step three, distilling the boron trichloride from which the heavy components are removed in the step two by using a second rectifying tower 3 to remove the light components in the boron trichloride.

In the second step, the method for pressing boron trichloride into the first rectifying tower 2 comprises the following steps: the steel cylinder is heated, the saturated vapor pressure of the steel cylinder is increased, and the liquid boron trichloride is pressed into the first rectifying tower 2 through the air pressure. A flowmeter is arranged on a pipeline between the raw material tank 1 and the first rectifying tower 2, and the flow of the boron trichloride can be accurately controlled.

In the second step, before distilling the boron trichloride, the first rectifying tower 2 is replaced and purged, the index content in the tower, such as water content, is measured, the first rectifying tower 2 is subjected to pressure maintaining treatment after the index is qualified, and the boron trichloride can be distilled after the pressure maintaining treatment is finished.

In the second step, the temperature of the tower kettle of the first rectifying tower 2 is 20-70 ℃, the temperature of the tower top is 0-30 ℃, and the reflux ratio is 3-100. Preferably, the number of the tower plates of the first rectifying tower 2 is 20-50, the temperature of the tower bottom is 30-60 ℃, the temperature of the tower top is 10-20 ℃, and the reflux ratio is 10-50.

In the third step, the tower bottom temperature of the second rectifying tower 3 is 0-50 ℃, the tower top temperature is 0-30 ℃, preferably, the number of tower plates of the second rectifying tower 3 is 50-100, the tower bottom temperature is 20-30 ℃, the tower top temperature is 10-20 ℃, and the reflux ratio is 100-800.

In the description of the present application, it is to be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "connected," and "connected" are to be construed broadly, e.g., as meaning either a fixed connection, a removable connection, or an integral connection; can be mechanically or electrically connected;

they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meaning of the above terms in the present application can be understood by those of ordinary skill in the art through specific situations.

The previous description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the present invention. Various modifications to the above-described embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the invention. Thus, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. The utility model provides a purification device of high-purity boron trichloride which characterized in that:

comprises a raw material tank, a first rectifying tower, a second rectifying tower and a finished product tank;

the first rectifying tower is provided with a liquid phase inlet and a gas phase outlet, and the liquid phase inlet is connected with the raw material tank through a pipeline;

the second rectifying tower is provided with a gas phase inlet and a liquid phase outlet, the gas phase inlet is connected with the gas phase outlet through a pipeline, and the liquid phase outlet is connected with the finished product tank through a pipeline.

2. The purification apparatus of high-purity boron trichloride according to claim 1, characterized in that:

and a filter and a flowmeter are arranged on a pipeline connecting the liquid phase inlet and the raw material tank.

3. The purification apparatus of high-purity boron trichloride according to claim 1, characterized in that:

and a regulating valve is arranged on a pipeline connecting the gas phase inlet and the gas phase outlet.

4. The purification apparatus of high-purity boron trichloride according to claim 1, characterized in that:

the first rectifying tower comprises a tower kettle, a tower body, a condenser and a reboiler, the tower kettle, the tower body and the condenser are sequentially connected from bottom to top, and the reboiler is connected with the tower kettle through a pipeline;

and tower plates are arranged in the tower body, and the number of the tower plates is 10-100.

5. The purification apparatus of high-purity boron trichloride according to claim 1, characterized in that:

the second rectifying tower comprises a tower kettle, a tower body, a condenser and a reboiler, the tower kettle, the tower body and the condenser are sequentially connected from bottom to top, and the reboiler is connected with the tower kettle through a pipeline;

and tower plates are arranged in the tower body, and the number of the tower plates is 10-200.

6. The purification apparatus of high-purity boron trichloride according to claim 1, characterized in that:

the first rectifying tower and the second rectifying tower are packed towers.

7. The purification apparatus of high-purity boron trichloride according to claim 1, characterized in that:

the raw material tank and the finished product tank are steel cylinders.