KR960006132B1 - Gas supply system having a multi-branch - Google Patents

Abstract

The system which can down the reactors totally or respectively in emergency and operate each process respectively is disclosed. Fuzzy process, leakage check process and gas supplying process using the system is also disclosed. The gas supply system includes a gas box; a gas supply inlet formed in the gas box; a main gas supply piping extending from the gas supply inlet; at least two main gas supply branch pipes connected to the supply piping; and reactor devices connected to ends of respective branch pipes.

Description

The Detachable Gas Supply System

1A is a schematic diagram of a conventional gas supply device.

FIG. 1B is a schematic internal view of the gas box G in FIG. 1.

2 is a schematic internal view of a multi-segment gas supply system of the present invention.

3A and 3B are gas flow charts in a purge process using the multi-segment gas supply system of the present invention.

4A and 4B are schematic views showing a leak check process using the multi-segment gas supply system of the present invention.

5 is a gas flow diagram in a gas supply process using the multi-segment gas supply system of the present invention.

Buch's blindness to the main parts of the drawing

G: Gas box A: Gas supply port

P: Main gas supply pipe BP1-BP4: Supply branch pipe

R1-R4: Reactor AV: Valve

RG1-RG4: Pressure Regulator PT1-PT4: Pressure Sensor

BP'1-BP'4: First purge gas supply branch pipe

BP "1-BP" 4: 2nd purge gas supply branch pipe

VG: vacuum generator.

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gas supply system, and more particularly to a multi-segmented gas supply system and control method in which gas supply is automatically controlled in the chemical, pharmaceutical and semiconductor industries using special gases.

The semiconductor integrated circuit is completed through predetermined manufacturing processes including a cleaning process, an oxidation process, an impurity implantation process, an etching process, and the like for a semiconductor material wafer such as silicon.

Such semiconductor integrated circuits have been highly integrated with the cell size of less than half micro units due to the recent development of the semiconductor industry. Therefore, when very minute dust particles or contaminated air are infiltrated in the manufacturing process, such as leakage junction or abnormal breakdown, This will cause a serious and adverse effect on the entire semiconductor chip. Therefore, in order to obtain high quality chips, it is necessary to perform the semiconductor manufacturing process in a high-purity atmosphere in which such minute dust or contaminated air is removed. Also, the semiconductor manufacturing process such as etching, deposition, and sputtering is extremely small and less than half micro units. There is a need to accurately shape the structure of the fine cell without errors. That is, in order to obtain a high quality chip, the shape of the insulated or contacted pattern in the cell must be manufactured with high accuracy without error, and thus requires a high degree of precision in an oxidation process, an etching process, a deposition process, or a sputtering process. do. Further, semiconductor manufacturing, etc. Ion implantation process as the injection gas of type P A _s H _3, B ₂ H ₆ gas, such A _s H ₃ to primarily use such PH ₃ gas of N-type, B ₂ H ₆ In addition, PH ₃ is extremely toxic and is filled in containers at high pressure. Therefore, there is a need for a device that can safely use these toxic gases and maintain high purity. That is, the apparatus should have a leakage range of 1 × 10 ^-10 cc / sec (0.0029 cc / year) or less, even at high pressures of 2000 PsiG or higher, and dust of 0.1 μ3EA or less. Therefore, there is a need to use safer, more efficient, and more productive equipment, resulting in a significant increase in manufacturing costs. However, in spite of such expensive equipment, if an accident occurs in the peripheral auxiliary equipment, there is a problem that the efficiency value of investment is reduced because the entire production equipment cannot be operated.

Hereinafter, a conventional multi-segment gas supply system having such a problem will be described with reference to FIG. 1.

In general, a gas supply device used in semiconductor manufacturing is shown in FIG. 1A, and the gas box G is connected to a low pressure chemical vapor deposition (LPCVD) device 1 and an LPCVD device through a reactor supply port A '. (2), the APCVD (Atmosphere Pressure CVD) device (3), the PECVD (Plasma enhanced CVD) device (4) is connected in parallel with the pipe, each of the devices (l, 2, 3, 4) connection to the pipe line The air block valves AV1, AV2, AV3, AV4, pressure regulators RG1-RG4, and filters F1-F4 are connected to each branch continuously.

For reference, in order to supply the semiconductor process gas (except N ₂ , O ₂ , He, Ar), which are toxic or non-toxic gases, as shown in FIG. 1B of FIG. It is communicated with the reactor supply port. It is also preferable to use the above 1BTL 1BOX type gas box.

The 1BTL 1BOX type gas box is described in Korean Patent Application Nos. 14808/92 and 117749/92 by the present applicant, and the gas box will be described below (see FIG. 1B).

Supply pipe 12 for supplying the process gas in the gas cylinder 11 to the reactor is provided, the supply pipe is an air valve (V ₄ ), pressure regulator (RG), another air valve (V ₅ ), fine Filters for filtering particles are sequentially installed, and the discharge pipe 15 is connected to the supply pipe 12 and the purge gas inlet pipe 13 at the process gas inlet I of the supply pipe 12. A first pipe and a second pipe connected to the supply pipe 12 at a predetermined position immediately before the air valve V ₅ , and a third pipe joined to the outlet by joining the first pipe and the second pipe. In the first and second pipes, air valves (V ₅ , V ₇ ) and check valves (CV ₆ , CV ₇ ) are installed, respectively, and a predetermined position of the third pipe (VG: vacuum generator) Is installed, another purge gas inlet pipe (14) is connected to the vacuum generator (VG) is installed, the gas inlet pipe (14) An air valve V ₈ flow meter FM and a check valve CV ₈ are provided inside.

The above configuration is provided for purging toxic or non-toxic gas in the supply pipe 12 between the gas cylinder 11 and the reactor supply port A '.

The conventional gas supply device has a configuration in which gas is supplied from the gas box to the reactor through a supply pipe line as shown in FIG. 1A.

According to such a conventional gas supply system, if a problem such as process gas remaining in the system due to insufficient purge occurs, the LPCVD apparatus or the like may generate a vacuum by itself, so that the valve is closed after closing the valve. The gas may be sucked in a vacuum to remove the remaining gas. However, the APCVD apparatus or the like cannot form a vacuum by itself, so a process of purging by supplying N ₂ from the gas box should be performed. In order to carry out the maintenance process such as N ₂ gas purge process, it is necessary to postpone the maintenance process in the future by judging the four reactors shown at the same time or the progress of the process. Failure to do so in a timely manner can lead to more fatal problems.

In addition, the leak or fire occurs in each reactor or pipe, a problem arises in that all the equipment must be down. In addition, if a problem occurs in the gas box, there is a problem that all the equipment should be down. In addition, as shown in FIG. 1A, process gas introduced with fine dust remains between fine connection gaps of air valves, pressure regulators, and the like, thereby causing high pollution.

Accordingly, an object of the present invention is to reduce the total number of reactors individually or individually in an emergency, to operate the leak check process, purge process, or the like as a whole or separately, and to operate various indicators and valves automatically or manually. will be.

In order to achieve the above object, the multi-segment gas supply system of the present invention includes a gas box, a gas supply port formed in the gas box, a supply pipe extending from the gas supply port for gas supply, and a branch form in the supply pipe. And two or more supply branch pipes connected to each other, and a reactor connected to the ends of the branch pipes, wherein the supply pipes include a first air valve, and each branch pipe includes a second air valve, a pressure regulator, The fifth air valves are connected in order, respectively, and a purge gas device supply port is provided, and a pipe is extended from the supply port of the purge gas device and branched from the first predetermined portion (a) to supply the first purge gas, respectively. A branch pipe is formed, and each of the purge gas supply branch pipes is connected to a portion between the second air valve and the pressure regulator of the main gas supply pipe via a third air valve. And a vacuum generator is installed in the second predetermined portion and branches therein to form a second purge gas supply branch pipe, each purge gas supply branch pipe being the main gas supply branch via a fourth air valve. It is characterized in that each through the connection between the pressure regulator of the pipe and the fifth air valve.

It is still another object of the present invention to provide a method of performing a purge process, a leak check process, and a gas supply process using the multi-segment gas supply system.

Hereinafter, with reference to FIG. 2, the preferred embodiment of the multi-segment gas supply system of the present invention will be described in detail.

A gas box G is installed, and a gas supply port A is formed in the gas box G, and a main gas supply pipe P extending from the gas supply port A is installed for gas supply. At the end of the supply pipe P, for example, four main gas supply branch pipes BP1-BP4 are formed. An air valve AV ₁ is installed at the front of the branch of the supply pipe P. The first to fourth branch pipes BP1-BP4 include second air valves AV ₁₂ , AV ₂₂ , AV ₃₂ , AV ₄₂ , pressure sensors PT1-PT4, and fifth air valves AV ₁₅ , AV. ₂₅ , AV ₃₅ , and AV ₄₅ ) are connected in order by branch.

The N ₂ purge gas supply port of the N ₂ purge gas device is installed therefrom, and the purge gas supply pipe extends therefrom, and is branched at a predetermined portion (a) so as to penetrate through the branch form with the first to fourth branch pipes. 1 purge gas supply branch pipe (BP'1-BP'4) is formed, the preferred position of the through connection portion of the second air valve (AV _l2 , AV ₂₂ , AV ₃₂ , AV ₄₂ ) and the pressure regulator ( Third air valves AV _l3 , AV ₂₃ , AV ₃₃ and AV ₄₃ are respectively provided in each of the first purge gas supply branch pipes between RG1-RG4 and immediately before their respective connecting portions, to prevent backflow of the purge gas. For this purpose, check valves (CV _1l , CV ₂₁ , CV _3l , CV ₄₁ ) are installed at the front of each air valve. On the other hand, the N ₂ purge gas supply pipe continues to extend and the air valve (AV ₂ ), the check valve (CV ₁ ) and the vacuum generator (VG) are sequentially installed at appropriate portions, and again in the vacuum generator (VG) portion. The branch is connected to the first through fourth branch pipes in the form of a branch through the second purge gas supply branch pipe (BP''1-BP''4) is formed, the preferred position is the pressure sensor Between the PT1-PT4 and the fifth air valves AV ₁₅ , AV ₂₅ , AV ₃₅ , AV ₄₅ , the second purge gas supply branch pipe immediately before the respective connecting portion has a fourth air valve AV ₁₄ , AV _24. , AV ₃₄ , AV ₄₄ ) will be installed. In order to prevent backflow of purge gas, check valves (CV ₁₂ , CV ₂₂ , CV ₃₂ and CV ₄₂ ) are installed in front of each air valve.

In addition, after the fifth air valve at the rear end of each branch pipe of the gas supply pipe, an access flow switch that generates a signal to shut off the gas supply valve by estimating leakage or component damage when the gas flow rate exceeds the set value. (Excess fIow switch) (S1-S4) and the filter (F1-F4), which is a device for removing small particles and dust are installed in order for each branch, and the reactors are connected to the ends of the branch pipes.

Various processes performed using the semiconductor gas supply apparatus including such a multi-segment gas supply system, for example, a purge process, a leak check process, and a gas supply process will be described in turn.

First, when a toxic or non-toxic gas inside the gas supply device is to be removed during a semiconductor process, a purge process is performed. The purge process is divided into two types.

The first is to discharge gas from the entire supply pipe using a vacuum generator, and the second is to discharge gas to the reactor. As shown in FIG. 3A, first, when the gas inside the supply pipe is discharged, all of the second, third, fourth, and fifth valves are closed, and the air valve AV ₂ is opened to open the vacuum generator VG. ), The pressure sensor (PT5) reaches a vacuum of -14.7 Psi or less, and then the fourth valve is opened to form the entire vacuum of the pipe, the fourth valve is closed, and the air valve (AV ₂ ) is closed, and the third air The valve is opened and the third air valve is closed when the N ₂ pressure is formed at a preset pressure (60 Psi) in the supply pipe line, and is performed by repeating the above process several times in turn.

The second is to open the first 3B As shown in Figure, in the case of discharging the gas to the reactor, the air valve (AV ₂₎ and air valve (AV _12, AV ₁₄₎ the air valve (AV _13, AV ₁₅₎ close N ₂ This is done by blowing purge gas into the reactor and evacuating the reactor.

These two purge processes must be started at a pressure of 0 Psi or less in PT1, and the remaining gas must be purged after the gas is discharged to the reactor. There should be no gas emissions.

This purge process, because the internal structure of each branch pipe is configured to be the same can be performed alone or in combination for each branch pipe, as shown in Figure 2, each pressure regulator (RG1-RG4) Pressure sensor (PTl-PT5) was installed in the vicinity of the vacuum generator (VG) so that the pressure can be displayed in a digital manner instead of an analog method. Various valves are automatically or manually operated using a solenoid valve.

Next, in this semiconductor device field, a vacuum close to absolute vacuum is essential and there should be no leakage, so a check process for leakage is described.

All materials cannot maintain the form of absolute vacuum, and even though they are completely sealed according to the time and the surrounding environment, the pressure increases due to communication with the surrounding air pressure over time. Containers, valves, and tubes under pressure can leak, even in very small quantities. Even when a small amount of gas leakage occurs, it is very dangerous if it is explosive, corrosive or toxic. In general, leakage is difficult to check that the degree of measurement is less than 1 × ^{10 −11} / sec, that is, 0.000 000 000 01 cc / sec. Toxicity to the human body represents the toxic gas contained in the air breathed by human exposure in units of one millionths (PPM) and is a function of the exposure time. To make this clearer, look at TLV (THRESHOLD LIMIT VALUES) = (the safe gas allowance when a person works for 8 or 40 hours),

The following is the amount of leakage rate per unit time in CC.

Better methods include the He leak detector and the Hi-PRESS leak test, but the more sophisticated test method uses the He leak detector, which is a time-consuming disadvantage. Currently, check out the facilities available to ^10-11.

4A and 4B show a leak check portion. In FIG. 4A, all air valves AV ₁₂ -AV ₁₅ are closed and the pressure is 0 Psi at the portion indicated by the thick line. Injecting is carried out. In general, if it is 0 Psi within 24 hours, it is determined that there is no leakage.

In FIG. 4B, the leak is checked at the portion indicated by the thick line from the air valve AV ₁₂ to the valve inside the reactor. Similarly, if 0 Psi is within 24 hours, it is determined that there is no leak. Thereafter, as shown in FIG. 5, a gas supply process is carried out for the process treatment in the system, and this gas supply must go through a purge process-leak check process. To -14.7 Psi, the air valves AV ₁₃ and AV ₁₄ are closed and the air valves AV ₁₂ and AV ₁₅ are opened to be executed. In this case, the pressure sensor PT1 is opened after the air valve AV _l2 is opened. ) If the displayed pressure is not high pressure (typically 60 Psi or more) or low pressure (typically 25 Psi or less), the air valve (AV ₁₅ ) is opened to supply gas, but if it is out of the above high pressure or low pressure range, the air valve (AV ₁₅ ) is controlled to not open, and at the same time an alarm is triggered (AV ₁₂ ) to close.

Like the purge process, the leak check process and the gas supply process may be performed independently or in combination with each branch pipe, since the internal structure of each branch pipe is the same, and various valves may be operated solely or manually. To operate.

As described above, as shown in FIG. 2 in the branch supply pipe, the air valve AV ₁ functions as a main valve, so that the air valve AV ₁ is closed first when the entire shutdown occurs.

When the N ₂ purge process is performed, the air valve AV ₁₂ is closed first, and the air valve AV _l3 is opened, but the air valve AV ₁₃ is opened when the pressure is sensed by the pressure sensor PT1 and is 0 Psi or less. When the pressure regulator RG1 is damaged and replaced, the air valve AV ₁₂ and the air valve AV ₁₅ are closed, and the N ₂ gas is diluted with the air valve AV ₁₄ and then vacuumed through the vacuum generator VG. The air valve AV ₁₄ is opened only when the vacuum value at the pressure transducer PT5 is formed to be -14.7 Psi or more. In general, when N ₂ is supplied to the reactor, the air valve (AV ₁₂ ) is closed and the pressure in the pressure sensor (PTl) becomes 0 Psi or less, and then the air valve (AV ₁₃ ) is opened first and the N ₂ gas pressure reaches the set value. The device opens the air valve AV ₁₅ .

Alternatively, the gas must be supplied after repurging and the pressure sensor (PTl) determines whether there is an abnormal pressure, and when the gas exceeds the set value in the access flow switch (EFS), the air valve AV ₁₂ automatically operates. Will be closed. If gas is to be supplied, it should be done after completing the purge-leak check-purge process as mentioned above, which serves to increase the life of the multi-segment gas supply system of the present invention. In addition, when a problem occurs in the reactor, the air valve AV ₁₂ is closed, but when the problem occurs in the multi-segment gas supply system, the air valve AV ₁ is configured to close (see FIG. 2).

The leak check process is divided into two types, the first of which is to check the multi-separation type itself, and the second to leak check the valve connected to the front end of the reactor. When leak checking the multi-slice type itself, close the air valves (AV ₁₂ , AV ₁₅ , AV ₁₄ ), and after reaching 0 Psi or less from the pressure sensor (PT1), open the air valve (AV _l3 ) and inject pressure about 80 Psi. The leak check up to the front end of the reactor is the same as above, but the air valve (AV ₁₅ ) is opened and must be purged. In this case, the pressure is automatically detected by the set time and the pressure sensor PTl detects the pressure. After about 3-10 minutes of stabilization time, a leak check is made in PT1, and if there is a difference between the pressure at the start and the pressure at the end, an alarm is generated to indicate the leak condition.

Consecutive use contributes to increased device efficiency, productivity and cost savings.

In other words, if any abnormality occurs during the use of the equipment, each piping line of the gas supply system is separated, so it is not necessary to shut down the entire system. RS232 communication is also available, enabling shutdown remote control and gas pressure data remote control.

Claims (11)

A gas box G, a gas supply port A formed in the gas box, a main gas supply pipe P extending from the gas supply port A for gas supply, and a supply pipe P. In the multi-segment gas supply system comprising at least two main gas supply branch pipes BP1 to BP4 connected in branch forms, and reactor devices R1, R2, R3, and R4 connected to ends of the respective branch pipes. The first air valve AV ₁ is installed in the main gas supply pipe P, and the second air valves AV ₁₂ , AV ₂₂ , AV ₃₂ , and AV are installed in each of the main gas supply branch pipes BP1 to BP4. _42), connected as a pressure regulator (RG1~RG4) and a fifth air valve _{(AV 15, AV 25, AV} 35, AV 45) , respectively, the order is, the purge gas supply port is installed at a predetermined position, the purge gas The piping extends from the supply port of the apparatus and is branched at the first predetermined portion (a) to form first purge gas supply branch pipes BP'1 to BP'4, respectively. And, a purge gas supplying branch tubes, each check valve _{(CV 11, CV 21, CV} 31, CV 41) and the third air valve via the _{(AV 13, AV 23, AV} 33, AV 43) Main gas branch The second air valve AV ₁₂ , AV ₂₂ , AV ₃₂ , AV ₄₂ of the pipe BP1-BP4 and the pressure regulators RG1 to RG4 are connected in a through manner, and a vacuum generator is connected to the second predetermined portion. And branched therein to form second purge gas supply branch pipes BP " 1 to BP " 4, respectively, which purge gas supply branch pipes are provided with check valves CV ₁₂ , CV ₂₂ , CV ₃₂ , CV ₄₂ , and Pressure regulators RG1 to RG4 of the main gas supply branch pipe BP1-BP4 and the fifth air valve AV ₁₅ , AV ₂₅ , via the fourth air valve AV ₁₄ , AV ₂₄ , AV ₃₄ , AV ₄₄ . AV ₃₅ , AV ₄₅ are each penetratingly connected, the multi-segment gas supply system, characterized in that the operation is performed automatically or manually. The method of claim 1, wherein an access flow switch is further installed below the fifth air valve of each branch pipe to generate a signal to shut off the gas supply valve when the gas flow rate exceeds a predetermined set value. Multi-segment gas supply system. The pressure regulator (PT1-PT4) is provided in the pressure regulators RG1 to RG4, and a pressure sensor (PT5) is installed in a predetermined portion near the vacuum generator (VG) to read the pressure. Multi-segment gas supply system, characterized by driving a valve. According to claim 1, wherein the pressure regulator (RG1-RG4) and the vacuum generator (VG) in the vicinity of the multi-segment gas supply system characterized in that the pressure is represented in a digital manner by installing a pressure sensor (PTl-PT5). In the process of purging the inside of the supply pipe with N ₂ gas by using the multi-segment gas supply system of claim 1, the second, third, fourth, and fifth valves are all closed, and the air valve AV ₂ is opened to vacuum. When the generator VG is operated, the fourth valve is opened to form a vacuum, the fourth valve is closed, the air valve AV ₂ is closed, the third air valve is opened, and N ₂ pressure is formed in the supply pipe line. The three air valves are closed, and the above process is repeatedly executed several times in turn, and the above purge process can be selected or executed individually or in combination for each branch pipe (BP1 to BP4). Purge process inside the pipe. 6. The purge process according to claim 5, wherein the purge process starts when the pressure in the second purge gas branch pipe in which the process is performed is 0Psi-14Psi and when the purge pressure is 60Psi or more. In the process of purging the reactor by using the multi-segment gas supply system of claim 1, the air valve (AV ₂ ) and the second and fourth air valves are closed, and the third and fifth air valves are opened in sequence, and the N ₂ purge gas is discharged. The above purge process is carried out by blowing into the reactor, wherein the reactor purge process is characterized in that the branch pipes BP1 to BP4 and each reactor can be selected individually or in combination. In the process of checking for leaks in the supply pipe using the multi-segment gas supply system of claim 1, after closing all the second, third, fourth, and fifth air valves, the pressure inside the leak is set to 0 Psi or less, and the leak check is performed. The leak check process is carried out by injecting pressure, and the leak check process can be selected individually or in combination with respect to each branch pipe (BP1 to BP4). In the process of checking for leaks in pipes to the reactor using the multi-segment gas supply system of claim 1, the second, third and fourth air valves and the valves inside the reactor are closed and the fifth air valve is opened. The leak check pressure is injected after the pressure of 0 psi or less, and the leak check process may be performed independently or in combination with each branch pipe (BP1 to BP4) and each reactor. Leak check process. In the process of supplying gas to the reactor using the multi-segment gas supply system of claim 1, the third and fourth air valves are closed, and the air valve AV ₁ , the second and fifth air valves, and the valves inside the reactor. The gas supply process is characterized in that the opening and opening the process gas, the gas supply process can be selected or executed individually or in combination for each branch pipe (BP1 ~ BP4) and each reactor. The method of claim 10, wherein the pressure of the gas passing through the second air valve is not within a predetermined range. A gas supply process, characterized in that to control the fifth air valve does not open.