KR200247359Y1 - Gas line pumping system with a mass flow controller - Google Patents

Abstract

Disclosed is a mass flow controller (MFC) attachment type gas supply device.

The present invention includes a bypass line connecting the gas inlet and the outlet of the flow control device to pump without passing through the flow control device, thereby improving turn-around time (TAT) / conductivity during gas line pumping, and chamber contamination. Prevention can be implemented, and the gas line is kept clean at all times, thereby improving wafer yield.

Description

GAS LINE PUMPING SYSTEM WITH A MASS FLOW CONTROLLER}

The present invention relates to a gas supply device with a mass flow controller (hereinafter referred to as MFC) used in a semiconductor manufacturing process, and in particular, an MFC attached gas having a bypass line. It relates to a supply device.

In the semiconductor process using dry process gas, the MFC is mounted to control the flow of gas in order to perform the process at a precise flow rate for a predetermined time.

1 is a block diagram of a gas supply apparatus equipped with such an MFC.

As shown in FIG. 1, control of the MFC 30 is essential to pump gas from the gas cabinet 10 to the chamber 40 via the manual valve 20, the pneumatic valve 22, and the MFC 30. to be.

Gas pumping is required in a line connected to each chamber 40 from the gas cabinet 10 to the final stage for each gas, and the gas pumping is described as follows.

1) Full pumping is required for decompression leak testing at the first hook-up of the gas line.

2) Gas line pumping is required when process problems occur due to gas purity changes during the process.

3) Pumping is necessary when contaminants are generated in the gas line due to changes in liquefied gas characteristics.

4) When replacing the gas reservoir, pumping is necessary to remove the harmful or corrosive gas in the line.

5) Pumping is required when replacing the components of the gas line including the MFC 30.

As described above, the pumping of the gas line connected to the MFC 30 is one of the important processes in the overall semiconductor manufacturing process.

However, the supply line configured for each gas is connected to the chamber 40 via the MFC 30 in the gas cabinet 10, and the line length is considerably long, and the conductivity of the line diameter and the MFC 30 are reduced. The problem of pumping time has been raised due to the limitation of the flow rate controlled by.

That is, in the prior art, the pumping was performed by gated the MFC 30 attached to the gas line extending from the gas cabinet 10 when the gas line was pumped. As a result, the pump had a lot of time and was polluted due to poor line conductivity. Since the gas is introduced into the chamber through the MFC 30, there was a problem that the secondary contamination of the MFC 30 and the chamber 40.

Accordingly, the present invention has been made to solve the above-described problem, and provided with a bypass line connecting the gas inlet and the outlet of the MFC to pump without passing through the MFC, TAT (turn around time) / conductivity during the gas line pumping It is an object of the present invention to provide an MFC-attached gas supply device for improving the chamber contamination prevention.

In order to achieve this object, the present invention, in the MFC attached gas supply device for pumping the gas line connecting the gas cabinet, MFC, process chamber, the bypass connecting the gas inlet line of the MFC and the gas outlet line of the chamber Provided is an MFC attached gas supply device comprising a line.

1 is a block diagram of a conventional gas supply apparatus with a flow control device;

2 is a block diagram of a gas supply apparatus with a flow control device having a bypass line according to a preferred embodiment of the present invention;

3 is an effective pumping speed correlation graph according to the capacity of the flow control device when the bypass line is formed according to the present invention and when it is not;

Figure 4 is a correlation graph of the time to reach the vacuum state according to the capacity of the flow control device when the bypass line is formed according to the present invention and when not.

<Explanation of symbols for the main parts of the drawings>

10: gas cabinet

20: manual valve

22: pneumatic valve

30: flow control device (MFC)

40: process chamber

50: pump

60: bypass line

Hereinafter, with reference to the accompanying drawings will be described in detail a preferred embodiment of the present invention.

Prior to the description, the key technical gist of the present invention is to install a bypass line at the front end of the MFC and the chamber to remove the gas present in the line in a short time without passing through the MFC when pumping. It is possible to easily achieve the object of the present invention from the means.

FIG. 2 is a block diagram illustrating an MFC attached gas supply device having a bypass line according to a preferred embodiment of the present invention, and includes a gas cabinet 10, a manual valve 20, a pneumatic valve 22, and an MFC 30. ), Process chamber 40, pump 50 and bypass line 60.

First, the gas cabinet 10, the manual valve 20, the MFC 30, the process chamber 40, and the pump 50 have the same structure and function as the conventional MFC attached gas supply device, and thus, a detailed description thereof will be described. It will be omitted.

The bypass line 60 according to the present invention connects the gas inlet line of the MFC 30 and the gas outlet line of the process chamber 40. That is, the bypass line 60 allows gas to be bypassed to the next stage of the process chamber 40 without passing through the MFC 30 at the time of gas pumping.

The pneumatic valve 22 is formed in the gas inflow line of the MFC 30, and when the gas line is pumped, the operation is cut off by the control of the MFC 30, thereby bypassing the path of the gas flowing into the MFC 30 by the bypass line 60. ) To lead to

In other words, the present invention is to supply the gas through the same supply line (gas cabinet 10 → MFC 30 → process chamber 40 → pump 50) during the process, and pumping the gas line It was implemented to cut the pneumatic valve 22 to supply gas through the bypass line 60.

3 is an effective pumping speed correlation graph according to the MFC capacity when the bypass line 60 according to the present invention is formed in front of the MFC (30) or not.

As can be seen from the figure, it is understood that the effective pumping speed is faster when the bypass line 60 is formed (hatched) than when the bypass line 60 is not formed (not hatched). Could be. At this time, the smaller the MFC capacity is, the difference is remarkable, and it can be seen that the difference between the two cases decreases as the MFC capacity increases. In particular, when the MFC capacity is 10sccm, it can be seen that about 180 times the pumping speed difference occurs.

4 is a graph showing a correlation between vacuum arrival time according to MFC capacity when the bypass line 60 is formed in front of the MFC 30 according to the present invention.

As can be seen from the figure, it is understood that when the bypass line 60 is formed (not hatched), the vacuum arrival time is shorter than when the bypass line 60 is not formed (hatched). Could be. For example, after calculating the time to reach the vacuum by pumping a 150m long gas tube, when the MFC capacity is 10 sccm, the vacuum reaching time of the bypass line 60 is 128 times faster than the line passing through the MFC. You can create a state. However, as the MFC size increases, the difference decreases, but it can be seen that the MFC line takes more time than the bypass line in terms of the effect. That is, in the case of 1,000 sccm, it can be seen that the bypass line 60 is about 2.5 times faster than the line passing through the MFC. The general MFC size is 100 sccm or less, and this case may be excluded.

As mentioned above, although this invention was demonstrated concretely based on the Example, this invention is not limited to this Example, Of course, various deformation | transformation is possible in the range which does not deviate from the summary.

Therefore, the present invention can shorten the time required for gas line pumping, and there is an effect of preventing the MFC and the chamber from secondary contamination. In addition, the present invention can greatly improve the TAT, and since the gas line is always kept clean, there is an effect of improving the wafer yield.

Claims (2)

In a gas cabinet, a manual valve, a pneumatic valve, a mass flow controller (MFC), a gas supply device with a flow control device for pumping a gas line connecting the process chamber, And a by-pass line connecting the gas inlet line of the flow control device and the gas outlet line of the chamber. The method of claim 1, The pneumatic valve, It is formed in the gas inlet line of the flow rate control device, and when the gas line pumped by the blocking operation by the control of the flow rate control device, it is characterized in that to guide the path of the gas flowing into the flow rate control device to the bypass line. Gas supply device with flow control device