JP2000035151A - Process gas supply unit - Google Patents

Abstract

(57) [Problem] To solve the above problems and to provide a compact process gas supply unit. SOLUTION: In a process gas supply unit having an input on-off valve, a mass flow controller, and an outlet on-off valve, the inlet on-off valve and the outlet on-off valve are an input solenoid valve 17, an output solenoid valve 19, and are hollow. Bobbin 4
1 and a fixed core 40 attached to the hollow portion of the bobbin 41 from above and protruding downward.
A movable core 33 attracted to the fixed core 40 when the coil 32 is energized; and a movable core when the inner periphery is fixed to the movable core and the outer periphery is fixed to the solenoid valve body and the coil is not energized. And a leaf spring 34 that urges the valve seat 35 in the direction in which the valve seat 35 contacts the valve seat 39.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a process gas supply unit used in a semiconductor manufacturing process, and more particularly, to a compact process gas supply unit using an electromagnetic valve.

[0002]

2. Description of the Related Art Conventionally, a process gas supply unit for supplying a process gas such as an etching gas in a semiconductor manufacturing process has been developed. The semiconductor manufacturing process has shifted from a method of batch processing a plurality of wafers to a single wafer processing method of processing wafers one by one, and there is a strong demand for a smaller process gas supply unit. . In order to reduce the size of the process gas supply unit, the present applicant has proposed a process gas supply unit in which a supply valve, a purge valve, and a vacuum valve are connected to a block-shaped manifold by bolts from above according to Japanese Patent No. 2568365. ing.

FIG. 4 shows a configuration of a process gas supply unit using the above-mentioned manifold. This unit is shown in FIG.
1 is a specific example of the circuit diagram of FIG. First, the circuit diagram of FIG. 5 will be described. The process gas enters from the left end in the figure,
Exit from the right end. Check valve 2 is connected to manual valve 1 and check valve 2
Is connected to the regulator 3. Regulator 3
It is connected to an input valve 5 which is an air operation valve.
A pressure gauge 4 is connected in the middle of the flow path between the regulator 3 and the input valve 5. The input valve 5 is a mass flow controller 8
Connected to the input port of A purge gas source is connected to an input port of the mass flow controller 8 via a purge valve 6 and a check valve 7 which are air operation valves. An output port of the mass flow controller 8 is connected to an output valve 10 which is an air operation valve.
A vacuum pump as a vacuum source is connected to an output port of the mass flow controller 8 via a vacuum valve 9 as an air operation valve. The output valve 10 is a manual valve 1
Connected to 1. The outlet of the manual valve 11 is connected to a vacuum chamber in a semiconductor manufacturing process.

[0004] Next, referring to FIG. 4, a configuration embodying the circuit of FIG. 5 will be described. All equipment is bolted onto the mounting panel D. The manual valve 1 is fixed to the mounting panel D by a bracket Y1. To both ends of the manual valve 1, pipes 1a and 1b and a joint M are connected. The check valve 2 is connected to the downstream pipe 1b and the joint M. The check valve 2 is connected to the regulator 3 via a joint M and a pipe 3a. The regulator 3 is fixed to the mounting panel D by a bracket Y2 (the configuration is the same as the bracket Y1). Three-pronged pipes 5a and 4a are connected to the right end of the regulator 3 via a joint M. The pressure gauge 4 is connected to the three-pronged pipe 4a. The three-pronged pipe 5a has a joint M
Is connected to the manifold Z1. An input valve 5 and a purge valve 6 are mounted on the upper surface of the manifold Z1. A check valve 7 is connected to a port of the purge valve 6 of the manifold Z1 via a pipe 6a and a joint M. The check valve 7 is connected to a purge gas source (not shown) via a joint M. Here, the flow path from the check valve 7 to the pipe 6a is formed in the manifold Z1.

[0005] The manifold Z1 is fixed to the mounting panel D by a plate X1. Also, manifold Z
1 is connected to a mass flow controller block N. On the upper surface of the mass flow controller block N, a mass flow controller 8 is attached. The right end of the mass flow controller block N is a manifold Z2 on which the vacuum valve 9 and the output valve 10 are mounted on the upper surface.
(The configuration is the same as that of the manifold Z1). The manifold Z2 is fixed to the mounting panel D by a plate X2. The vacuum valve 9 is connected to a vacuum pump as a vacuum source. Here, the flow path from the vacuum source is formed in the plate X2 (the configuration is the same as that of the plate X1). The manifold Z2 is connected to the manual valve 11 via a joint M and a pipe 11a. The manual valve 11 is fixed to the mounting panel D by a bracket Y3 (the configuration is the same as the bracket Y1). The right end of the manual valve 11 is
b, connected to a vacuum chamber via joint M

Here, conventionally, commercially available products have been used as mass flow controllers. A commercially available mass flow controller includes a mass flow sensor unit, a flow control valve unit, and a controller unit.The controller unit is based on an output from the mass flow sensor unit in order to maintain a flow value given from the host computer to the controller. Thus, the flow control valve is controlled. In the conventional mass flow controller system, a pressure sensor for detecting the fluid pressure, a regulator for keeping the fluid pressure constant, and a shutoff valve for completely shutting off the fluid are separately provided upstream of the mass flow controller. ing.

[0007]

However, the conventional process gas supply unit has the following problems. (1) Since the on-off valves used as the input valve, the purge valve, the output valve, and the vacuum valve are air operation valves driven by compressed air, air piping is required for each valve. A large number of air pipes are routed to the process gas supply unit, which is a problem when realizing a compact process gas supply unit. Further, an electromagnetic valve for controlling air for driving the air operation valve is required, and there has been a problem that an extra space is occupied.

Here, the reason why the air operation valve has been used instead of using the electromagnetic on-off valve in the past is as follows. In the conventional solenoid valve, the movable iron core slides in the hollow portion of the bobbin. This is because particles are generated from the part, and when particles are generated in the semiconductor process, there is a problem that the yield of semiconductor products is reduced.

(2) In the conventional mass flow controller, a pressure sensor, a regulator, and a complete shutoff valve are
Since it is provided separately from the mass flow controller,
Extra space is required, and there is a problem that the demand for compactness cannot be met. Further, in the mass flow controller, since a thin tube is used as a mass flow sensor, clogging occurs when a corrosive gas or the like flows. in this case,
The entire mass flow controller must be replaced,
This was a problem because the unit price of the mass flow controller was high.

An object of the present invention is to solve the above problems and to provide a compact process gas supply unit.

[0011]

In order to achieve the above object, a process gas supply unit according to the present invention has the following configuration. (1) In a process gas supply unit having an inlet on-off valve, a mass flow controller, and an outlet on-off valve,
The inlet on-off valve and the outlet on-off valve are electromagnetic on-off valves, a coil wound around the outer periphery of a hollow bobbin,
A fixed core attached to the hollow part of the bobbin from above and protruding downward, a movable core attracted to the fixed core when the coil is energized, and an inner periphery fixed to the movable core and an outer periphery fixed to the solenoid valve body And a leaf spring for urging the movable iron core in a direction in which the valve seat comes into contact with the valve seat when the coil is not energized.

(2) In the process gas supply unit described in (1), the main controller serially transmits a control signal to a controller that controls two or more of the electromagnetic on-off valves provided in the process gas supply unit. It is characterized by doing.

(3) In a process gas supply unit having an inlet opening / closing valve, a mass flow controller, and an outlet opening / closing valve, the mass flow controller detects a pressure of the process gas and a mass flow rate of the process gas. A sensor pack including a mass flow sensor for controlling the pressure of the process gas, an electromagnetic pressure control valve for adjusting the pressure of the process gas, and an electromagnetic flow control valve for adjusting the flow rate of the process gas.

The operation of the process gas supply unit having the above configuration will be described. Since an electromagnetic on-off valve is used, no driving air piping is required, and the entire process gas supply unit can be made compact. When the coil is energized, the movable core is attracted to the fixed core projecting downward from the bobbin, and the valve element is separated from the valve seat.
At this time, the movable iron core is supported by a leaf spring,
Since the movable core does not contact the fixed core, no particles are generated. When the energization of the coil is cut off, the movable iron core is urged in the direction in which it comes into contact with the valve seat by the return force of the leaf spring, and comes into contact with the valve seat. Also at this time, since the movable iron core does not contact anything, no particles are generated.

Further, since the main controller transmits the serial signal to the terminal box, the number of wirings can be reduced, so that the entire configuration of the process gas supply unit can be made compact.

The pressure sensor of the sensor pack detects the gas pressure, and the valve opening of the electromagnetic pressure control valve is controlled based on the detected pressure, and the gas pressure is maintained at a predetermined value. In addition, the mass flow sensor of the sensor pack detects the mass flow of the gas, and the valve opening of the electromagnetic flow control valve is controlled based on the detected mass flow. As a result, the functions performed by the conventional pressure gauge, regulator, mass flow controller, and complete shutoff valve can be performed by the sensor pack, the electromagnetic pressure control valve, and the electromagnetic mass flow control valve of the present invention. Therefore, the entire process gas supply unit can be made compact. Further, when the mass flow sensor becomes clogged or the like, it is sufficient to replace the sensor pack, so that the replacement is easy and the cost can be reduced.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of a process gas supply unit according to the present invention will be described below in detail with reference to the drawings. FIG. 1 shows an overall configuration diagram of a process gas supply unit according to one embodiment of the present invention. From the left side of the block 20, the input solenoid valve 17, the purge solenoid valve 1
8, a pressure control solenoid valve 12, a sensor pack 13, a flow control solenoid valve 14, and an output solenoid valve 19 are attached by bolts from above. Here, in the sensor pack 13,
A pressure sensor 15 for detecting the pressure of the process gas,
A mass flow meter 16 for detecting the mass flow rate of the process gas is housed. Among them, the pressure control solenoid valve 12, the sensor pack 13, and the flow rate control solenoid valve 14 constitute the mass flow controller 11.

The block 20 includes an input flow path 21 connected to the input port of the input electromagnetic valve 17, an input purge flow path 22 connecting the output port of the input electromagnetic valve 17 to the input port of the purge electromagnetic valve 18, A purge passage 23 for supplying a purge gas to the valve 18, a purge pressure passage 24 connecting an output port of the purge solenoid valve 18 and an input port of the pressure control solenoid valve 12, an output port of the pressure control solenoid valve 12, and a flow control solenoid. A sensor flow path 25 communicating with the pressure sensor 15 and the mass flow meter 16 in the sensor pack 13 while connecting the input port of the valve 14, an output port of the flow control solenoid valve 14, and a flow rate connecting the input port of the output solenoid valve 19. An output flow path 27 connected to the output flow path 26 and the output port of the output solenoid valve 19 is formed.

The input port of the terminal box 29 is connected to the pressure sensor 15, the mass flow meter 16, and the main controller 30. A serial signal is transferred to a signal line connecting the terminal box 29 and the main controller 30. The terminal box 29 has a function as a serial-parallel converter that receives a serial signal and outputs it as a parallel signal to each solenoid valve.
In addition, signals received from the pressure sensor 15 and the mass flow meter 16 are converted into serial signals as serial signals.
Has the function of transmitting to Also, the terminal box 29
The output ports of the input solenoid valve 17 and the purge solenoid valve 1
8. The coil portions of the pressure control solenoid valve 12, the flow control solenoid valve 14, and the output solenoid valve 19 are connected.

Next, the input solenoid valve 17 and the purge solenoid valve 1
8. The basic structure of a solenoid valve used as the pressure control solenoid valve 12, the flow control solenoid valve 14, and the output solenoid valve 19 will be described. FIG. 2 shows a sectional view of the solenoid valve 31. A fixed iron core 40 is mounted on the bobbin 41 hollow portion of the coil 32 wound around the outer periphery of the hollow bobbin 41 from above, and protrudes out of the bobbin from below the bobbin 41. When the coil 32 is energized, the fixed iron core becomes an electromagnet. The valve body 38 has an input flow path 36, an output flow path 37, and a valve seat 39 formed at an end of the input flow path 36. The valve body 33 is held by a leaf spring 34 at a position where it comes into contact with or separates from the valve seat 39. FIG. 3 shows a detailed enlarged view of the valve element 33 and the leaf spring 34. FIG. 3A is a plan view seen from the leaf spring side,
(B) is AA sectional drawing of (a).

The leaf spring 34 is, as shown in FIG.
The structure is hollowed out by etching.
The valve body 33 is connected to the center of the leaf spring 34 by spot welding. The outer periphery of the leaf spring 34 is
The valve body 33 can be moved in the axial direction because the remaining portion after being hollowed out functions as a spring. The spring 34 constantly urges the valve body 33 with a return force for returning to the state shown in FIG. An elastic valve sheet 35 made of rubber or plastic is fixed to a portion of the valve body 33 made of metal, which is in contact with the valve seat 39, with an adhesive or the like.

Next, the operation of the process gas supply unit having the above configuration will be described. First, solenoid valve 3
1 will be described. When the coil 32 is energized, a magnetic field is generated in the fixed iron core 40, and the fixed iron core becomes an electromagnet to attract the valve element 33. The suction force overcomes the return force of the leaf spring 34 that attempts to hold the valve body 33 at the current position, so that the valve body 33 moves upward, and the valve seat 35 separates from the valve seat 39. At this time, the leaf spring 34
Only the remaining portion shown in (a) is deformed, and the valve body 33 is not in contact with any part. Therefore, there is no sliding portion and no particles are generated. As a result, the input flow path 36 and the output flow path 37 communicate with each other, and the process gas flows.

Here, if the value of the current supplied to the coil 32 is simply turned on and off, the solenoid valve also becomes a simple on / off valve. Input solenoid valve 17, Purge solenoid valve 18, Output solenoid valve 1
9 is a simple on / off valve. Further, the coil 32 has a characteristic in which the proportional band of the current value to the attraction force is large,
By changing the current signal, the solenoid valve 31 can function as a flow control valve. Pressure control solenoid valve 1
2. The flow control solenoid valve 14 is a flow control valve.

Next, when the power supply to the coil 32 is cut off, the magnetic field in the fixed iron core 40 disappears, and the force for attracting the valve body 33 disappears. , The valve seat 35 contacts the valve seat 39 with a predetermined force. Also in this movement, the leaf spring 34 only deforms the remaining portion shown in FIG. 3A, and the valve body 33 does not contact anywhere.
There is no sliding portion, and no particles are generated. Thereby, the input flow path 36 and the output flow path 37 are shut off, and the process gas is shut off.

Next, the operation of the process gas supply unit of FIG. 1 will be described. When supplying the process gas to the vacuum chamber, the main controller 30 transmits a serial signal to the terminal box 29, and the terminal box 29 converts the serial signal into a parallel signal, and converts the serial signal into a parallel signal.
The input solenoid valve 17 and the output solenoid valve 19 are opened with the 8 closed. As a result, the process gas flows out of the sensor pack 13. The pressure sensor 15 detects the pressure of the process gas and inputs the detected pressure to the controller 29. The mass flow meter 16 detects the mass flow rate of the process gas and inputs the detected mass flow rate to the main controller 30 via the terminal box 29. The main controller 30 controls the pressure control solenoid valve 12 via the terminal box 29 based on the pressure detected by the pressure sensor 15 to maintain the pressure of the process gas at a predetermined value. Further, the main controller 30 controls the flow control solenoid valve 14 via the terminal box 29 based on the mass flow rate detected by the mass flow meter 16 to maintain the mass flow rate of the process gas at a predetermined value. Usually, until the pressure and the mass flow rate of the process gas reach a predetermined value, the gas is discarded, and is supplied to the vacuum chamber after the pressure and the mass flow rate reach the predetermined values.

Next, when receiving a command to stop gas supply, the main controller 30 shuts off the output solenoid valve 19 and the input solenoid valve 17 via the terminal box 29. Thereafter, the purge solenoid valve 18 is opened, the process gas remaining in the flow path of the block 20 and the like is sucked, and the nitrogen gas purge is repeatedly performed, thereby repeating the block 20.
The process gas remaining in the inner passage and the like is replaced with nitrogen gas.

As described in detail above, according to the process gas supply unit of the present embodiment, the input on-off valve,
In a process gas supply unit having a mass flow controller and an outlet on-off valve, the inlet on-off valve and the outlet on-off valve are the input solenoid valve 17 and the output solenoid valve 19, and are wound around the outer periphery of a hollow bobbin 41. Coil 3
2, a fixed core 40 attached to the hollow portion of the bobbin 41 from above and protruding downward, a movable core 33 attracted to the fixed core 40 when the coil 32 is energized, and an inner periphery fixed to the movable core. A leaf spring 34 for biasing the movable iron core in a direction in which the valve seat 35 comes into contact with the valve seat 39 when the coil is not energized. Since no valve is used,
Since no driving air piping is required, the entire process gas supply unit can be made compact.

Further, according to the process gas supply unit of the present embodiment, the main controller serially transmits a control signal to a controller for controlling the two or more electromagnetic on-off valves provided in the process gas supply unit. Therefore, the number of wirings can be reduced, and the configuration of the entire process gas supply unit can be made compact.

According to the process gas supply unit of the present embodiment, in the process gas supply unit having the inlet on-off valve, the mass flow controller, and the outlet on-off valve, the mass flow controller detects the pressure of the process gas. Sensor 13 having a pressure sensor 15 for detecting the mass flow rate of the process gas, a pressure control solenoid valve 12 for adjusting the pressure of the process gas, and a flow control for adjusting the flow rate of the process gas The sensor pack 1 according to the present embodiment has the functions of the conventional pressure gauge, the regulator, the mass flow controller, and the complete shut-off valve because of having the solenoid valve 14.
3. The pressure control solenoid valve 12 and the flow control solenoid valve 14 can be used, and the whole process gas supply unit can be made compact. Further, when the mass flow meter 16 becomes clogged or the like, the sensor pack 13 need only be replaced, so that the replacement is easy and the cost can be reduced.

It should be noted that the present invention is not limited to the above-mentioned embodiment at all, and can be carried out as follows without departing from the spirit of the present invention. For example, in each of the above embodiments, the pressure sensor 15 and the mass flow meter 16 are fixed in the sensor pack 13, and when the mass flow meter 16 fails, the entire sensor pack 13 is replaced. The pressure sensor 15 may be used as it is by replacing only the mass flow meter 16.

[0031]

According to the process gas supply unit of the present invention, in a process gas supply unit having an input on-off valve, a mass flow controller, and an outlet on-off valve,
The inlet opening and closing valve and the outlet opening and closing valve are solenoid valves, a coil wound around the outer periphery of a hollow bobbin, a fixed iron core mounted on the hollow portion of the bobbin from above and protruding downward, and a coil. The movable iron core is attracted to the fixed iron core when energized, and the inner seat is fixed to the movable iron core, the outer periphery is fixed to the solenoid valve body, and the valve seat seats the movable iron core when the coil is not energized. Since it has a leaf spring that urges in the direction in which it comes into contact with the device, no air operation valve is used, and no driving air piping is required, so that the entire process gas supply unit can be made compact.

[Brief description of the drawings]

FIG. 1 is a diagram showing an overall configuration of a process gas supply unit according to an embodiment of the present invention.

FIG. 2 is a sectional view showing a structure of a solenoid valve used in the process gas supply unit of the present invention.

FIG. 3 is a detailed enlarged view of a valve body and a leaf spring used in the solenoid valve.

FIG. 4 is a diagram showing an overall configuration of a conventional process gas supply unit.

FIG. 5 is a circuit diagram of FIG. 4;

[Explanation of symbols]

 12 Pressure control solenoid valve 13 Sensor pack 14 Flow control solenoid valve 15 Pressure sensor 16 Mass flow meter 17 Input solenoid valve 18 Purge solenoid valve 19 Output solenoid valve 29 Terminal box 30 Main controller 33 Valve body 34 Leaf spring

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 3H065 AA01 BB11 CA07 3H066 AA01 BA12 BA17 BA38 3H106 DA07 DA13 DA23 DB02 DB12 DB23 DB32 DB38 DC02 DC17 DD03 EE30 EE34 EE42 EE48 FB11 FB12 FB40 GA24 GC26 KK01 KK31 503004 A

Claims (3)

[Claims] 1. A process gas supply unit having an inlet on-off valve, a mass flow controller, and an outlet on-off valve, wherein the inlet on-off valve and the outlet on-off valve are electromagnetic on-off valves, and a hollow bobbin. A coil wound around an outer periphery of the bobbin, a fixed core mounted on the hollow portion of the bobbin from above and protruding downward, and a movable core attracted to the fixed core when the coil is energized. A leaf spring whose periphery is fixed to the movable core, whose outer periphery is fixed to the solenoid valve body, and which urges the movable core in a direction in which the valve seat comes into contact with the valve seat when the coil is not energized. And a process gas supply unit. 2. The process gas supply unit according to claim 1, wherein the main controller serially transmits a control signal to a controller that controls two or more of the electromagnetic on-off valves provided in the process gas supply unit. A process gas supply unit, characterized in that: 3. A process gas supply unit having an inlet opening / closing valve, a mass flow controller, and an outlet opening / closing valve, wherein the mass flow controller detects a pressure of the process gas and a mass flow rate of the process gas. Process gas supply, comprising: a sensor pack having a mass flow sensor for controlling the pressure of a process gas; an electromagnetic pressure control valve for adjusting a pressure of a process gas; and an electromagnetic flow control valve for adjusting a flow rate of a process gas. unit.