JP3645115B2 - Substrate processing equipment - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention provides a substrate processing for performing a predetermined process on a semiconductor substrate, a glass substrate for a liquid crystal display device, a glass substrate for a photomask, a substrate for an optical disk (hereinafter simply referred to as “substrate”) in a chamber in which exhaust is performed Relates to the device.
[0002]
[Prior art]
Conventionally, in a substrate processing step, processing may be performed while supplying a gas to the substrate. For example, a light irradiation type heat treatment apparatus (lamp annealing) is one of such processes.
[0003]
FIG. 5 is a diagram showing a schematic configuration of a light irradiation type heat treatment apparatus which is an example of a conventional substrate processing apparatus. This light irradiation type heat treatment apparatus includes a chamber 110 for accommodating the substrate W and performing light irradiation heat treatment. A support part 115 for supporting the substrate W is provided inside the chamber 110. A plurality of lamps for performing light irradiation are provided above the chamber 110 (not shown).
[0004]
Further, a gate valve 120 is provided on the side of the chamber 110. The gate valve 120 can abut against the chamber 110 and can be separated. When the gate valve 120 is away from the chamber 110, the interior of the chamber 110 is opened, and a loading / unloading robot (not shown) loads the substrate W into the chamber 110 or unloads the substrate W from the chamber 110. On the other hand, when the gate valve 120 is in contact with the furnace port of the chamber 110 (the state shown in FIG. 5), the chamber 110 is closed and the inside becomes a sealed closed space.
[0005]
Further, as shown in FIG. 5, the apparatus includes a gas supply unit 130 that supplies gas to the chamber 110 and a gas exhaust mechanism that exhausts gas from the chamber 110. The gas supply unit 130 includes a gas supply source, a supply valve, a mass flow controller, and the like, and can supply a predetermined gas such as nitrogen gas or ammonia gas to the chamber 110 at a constant flow rate. On the other hand, the gas exhaust mechanism is configured by an exhaust damper 140. The exhaust damper 140 is provided in an exhaust path that connects an exhaust line outside the apparatus (generally a negative pressure line installed in a factory) and the apparatus. The exhaust damper 140 is configured using a butterfly valve, and the exhaust force supplied from the exhaust line to the chamber 110 can be adjusted according to the degree to which the butterfly valve is opened, that is, the exhaust flow rate from the chamber 110 can be adjusted. it can.
[0006]
When performing the heat treatment of the substrate W in the conventional substrate processing apparatus shown in FIG. 5, first, the gate valve 120 opens the chamber 110, the loading / unloading robot loads the substrate W into the chamber 110, and the substrate W enters the support portion 115. give. Next, after the chamber 110 is closed by the gate valve 120 and the inside thereof is closed, a predetermined gas is supplied from the gas supply unit 130 to the chamber 110 to perform gas replacement. Thereafter, the lamp is irradiated with light, and the substrate W is subjected to light irradiation heat treatment. After the heat treatment is completed, the gate valve 120 opens the chamber 110 again, and the loading / unloading robot unloads the processed substrate W from the chamber 110 to complete the series of processes.
[0007]
[Problems to be solved by the invention]
By the way, the purpose of providing the exhaust damper 140 in the exhaust path in the above-described conventional substrate processing apparatus is to flatten the fluctuation of the exhaust force supplied to the chamber 110. That is, the pressure in the exhaust line installed in the factory may fluctuate depending on the operating conditions of other devices. Even in such a case, the fluctuation of the pressure is alleviated by the exhaust damper 140 and the pressure in the chamber 110 is reduced. This makes it possible to supply exhaust power that is stable to some extent.
[0008]
However, when such an exhaust damper 140 is provided in the exhaust path, the following problems occur.
[0009]
First, the exhaust force supplied to the chamber 110 defined by the exhaust damper 140 is an exhaust pressure that is weak enough to reduce the ingress of outside air into the chamber 110 when the gate valve 120 opens the chamber 110. . This is for minimizing the outside air entrained in the chamber 110 when the substrate W is carried in and out. Therefore, in the gas replacement performed with the gate valve 120 closed with the chamber 110, the exhaust force is weak and active exhaust cannot be performed, so that the replacement efficiency is low, and as a result, the time required for the gas replacement is long. There was a tendency to become.
[0010]
On the other hand, in the state where the gate valve 120 opens the chamber 110, although the exhaust force supplied to the chamber 110 is a weak exhaust pressure, a slight air flow is generated in the vicinity of the furnace port of the chamber 110. . Such a flow of air promotes a state in which the outside air is about to enter from the furnace port of the chamber 110 to the inside. When outside air enters the inside of the chamber 110, contaminants such as particles flow in along with the outside air, which may become a contamination source of the substrate W.
[0011]
As described above, in the conventional exhaust damper 140, the optimum exhaust force is not defined in either the state where the gate valve 120 is open or the state where the chamber 110 is closed. That is, the exhaust force is too strong when the chamber 110 is open, and the exhaust force is too weak when the chamber 110 is closed.
[0012]
In order to solve this, it is conceivable to use a technique in which the butterfly valve of the exhaust damper 140 is driven by a stepping motor linked to a pressure sensor, and the exhaust force is changed depending on the open / close state of the chamber 110. However, there is a problem that the operation time required for changing the exhaust force is long, and the open / close state of the chamber 110 cannot be appropriately followed. In particular, in a single wafer light irradiation type heat treatment apparatus or the like, since the processing time of the substrate W is short and the open / close state of the chamber 110 changes in a short time, it is practically used when the operation time required for changing the exhaust force is long. It cannot withstand.
[0013]
The present invention has been made in view of the above problems, and an object of the present invention is to provide a substrate processing apparatus capable of rapidly changing the exhaust force supplied to the chamber according to the open / close state of the chamber.
[0014]
[Means for Solving the Problems]
In order to solve the above-mentioned problems, the invention of claim 1 is a substrate processing apparatus that performs a predetermined process on a substrate, and has a processing space for performing the process on the substrate and an opening for carrying in and out the substrate. A chamber to be formed; an opening / closing means for opening / closing the opening; an exhaust passage connected to the chamber for supplying exhaust force to the chamber; and an exhaust pressure provided to the chamber for switching an exhaust pressure to the chamber A gas pressure cylinder and a gas supply means for supplying gas to the chamber. When the opening is opened when the substrate is carried in and out of the gas pressure cylinder , the exhaust pressure to the chamber is reduced. When the gas is supplied from the gas supply means to the chamber when the gas is replaced, the opening is closed at the time of gas replacement in the chamber. And is greater atmospheric exhaust pressure than the small exhaust pressure of exhaust pressure against.
[0015]
According to a second aspect of the present invention, in the substrate processing apparatus according to the first aspect of the present invention, gas replacement in the chamber is performed after the substrate is loaded .
[0016]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
[0017]
FIG. 1 is a conceptual diagram showing a configuration of a substrate processing apparatus according to the present invention. The substrate processing apparatus 10 is a light irradiation type heat treatment apparatus that heats the substrate W by light irradiation. The substrate processing apparatus 10 includes a chamber 11 that forms a processing space for performing light irradiation heat treatment on the substrate W. The upper surface of the chamber 11 is made of a material that transmits light (quartz or the like), and a heating source using a lamp is provided above it (not shown). The substrate W carried into the chamber 11 is subjected to heat treatment such as annealing and CVD (Chemical Vapor Deposition) using light from the heating source.
[0018]
An opening 12 for carrying in / out the substrate W is formed on the side surface of the chamber 11, and the substrate processing apparatus 10 includes a gate valve 13 as an opening / closing means for opening / closing the opening 12. When the gate valve 13 is separated from the opening 12, the chamber 11 is opened, and a loading / unloading robot (not shown) loads the substrate W into the chamber 11 through the opening 12, or removes the substrate W from the chamber 11. Take it out. On the other hand, when the gate valve 13 is in contact with the opening 12 (state of FIG. 1), the opening 12 is closed and the inside of the chamber 11 is sealed.
[0019]
When the substrate W is loaded into the chamber 11, a loading / unloading robot that holds the substrate W enters the chamber 11 through the opening 12, and the substrate W is received by being pushed up by the plurality of pins 14 in the chamber 11. . Thereafter, after the carry-in / out robot leaves the chamber 11, the pins 14 are lowered and the substrate W is placed on the support portion 15. When the substrate W is unloaded, an operation opposite to the loading is performed.
[0020]
The substrate processing apparatus 10 includes a gas supply unit 20 that supplies a processing gas to the chamber 11 so that the substrate W is processed in a predetermined processing gas. The gas supply unit 20 appropriately selects or mixes gas supply pipes 21 serving as gas supply paths to the chamber 11, gas supply sources 22 serving as various gas supply sources, and gases from the respective gas supply sources 22. And a supply control unit 23 that leads to the gas supply pipe 21 at a predetermined flow rate.
[0021]
In addition, the substrate processing apparatus 10 includes a gas exhaust unit 30 that exhausts gas from the inside of the chamber 11. The gas exhaust unit 30 includes an exhaust pipe 31 and an exhaust pressure switching unit 40. The exhaust pipe 31 connects the exhaust line outside the apparatus and the lower part of the chamber 11, and has a role as an exhaust path for supplying exhaust force from the exhaust line to the chamber 11. The exhaust pressure switching unit 40 is provided in the middle of the exhaust pipe 31 and has a role as exhaust pressure switching means for switching exhaust force to the chamber 11, that is, exhaust pressure to the chamber 11.
[0022]
The description of the exhaust pressure switching unit 40 will be further continued. 2 and 3 are diagrams illustrating an example of the configuration of the exhaust pressure switching unit 40. FIG. As the exhaust pressure switching unit 40 in the present embodiment, an exhaust pressure regulator capable of controlling the exhaust force at two arbitrary points is used.
[0023]
The exhaust pressure switching unit 40 includes valve seats 41, 42, 43, a cylinder 44, a spring 46, and a valve body 47. The three valve seats 41, 42, and 43 define gas flow paths and are engaged with the valve body 47. The three valve seats 41, 42, and 43 are drawn separately for convenience of illustration, but these are formed as a single body to constitute one valve seat.
[0024]
A flow path 48 formed by the valve seat 42 and the valve seat 43 is connected to the exhaust pipe 31 and communicated with the chamber 11. A flow path 49 formed by the valve seat 41 and the valve seat 42 is connected to the exhaust pipe 31 and communicated with the exhaust line. Therefore, the gas exhausted from the chamber 11 flows into the exhaust pressure switching unit 40 from the flow path 48, flows out from the flow path 49, and is discharged to the exhaust line.
[0025]
On the other hand, a valve body 47 is slidably fitted in a passage defined by the valve seat 41 and the valve seat 43. As shown in the figure, the valve body 47 is connected to the piston 45 of the cylinder 44 via a spring 46. Here, the cylinder 44 is a gas pressure type cylinder driven by nitrogen gas. Therefore, the cylinder 44 can take only two modes: a state in which the nitrogen gas is supplied and the piston 45 is extended, and a state in which the nitrogen gas is discharged and the piston 45 is contracted.
[0026]
FIG. 2 shows a state where the cylinder 44 extends the piston 45. In this state, when the piston 45 extends, the spring 46 and the valve body 47 are pushed out, so that the valve body 47 blocks between the flow path 48 and the flow path 49. However, the valve body 47 does not completely block between the flow path 48 and the flow path 49, but blocks it with a minute gap left as shown in FIG. Therefore, the flow channel 48 and the flow channel 49 are communicated with each other through the minute gap. As a result, the exhaust force supplied from the exhaust line to the chamber 11 via the exhaust pressure switching unit 40 becomes minute, in other words, the exhaust pressure with respect to the chamber 11 becomes minute (small exhaust pressure). .
[0027]
On the other hand, FIG. 3 shows a state in which the cylinder 44 contracts the piston 45. In this state, when the piston 45 contracts, the spring 46 and the valve body 47 are pulled back, and the valve body 47 does not hinder the communication between the flow path 48 and the flow path 49. Therefore, the exhaust force supplied from the exhaust line to the chamber 11 via the exhaust pressure switching unit 40 becomes large. In other words, the exhaust pressure with respect to the chamber 11 is large (large exhaust pressure; Is of course smaller than the large exhaust pressure).
[0028]
Next, a substrate processing procedure in the substrate processing apparatus 10 of the present embodiment will be described. First, the gate valve 13 opens the opening 12, and the loading / unloading robot loads the substrate W into the chamber 11. At this time, the exhaust pressure switching unit 40 takes the state shown in FIG. 2, that is, the piston 45 is extended. Therefore, as described above, the exhaust pressure with respect to the chamber 11 becomes a small exhaust pressure, and a small amount of exhaust is performed from the chamber 11. The gas exhausted from the chamber 11 flows as indicated by arrows A20, A21, A22, A23 and is exhausted to the exhaust line. At this time, even if the pressure in the exhaust line fluctuates, the fluctuation is absorbed by the spring 46 and flattened, so that a minute exhaust pressure can be stably applied to the chamber 11.
[0029]
Since the exhaust pressure is applied to the chamber 11 even though it is minute, no stagnation of air occurs in the chamber 11. Further, since the exhaust pressure is very small, the air flow accompanying the exhaust does not promote a state in which the outside air is about to enter from the opening 12 of the chamber 11. In other words, it is necessary to adjust the state in which the piston 45 of the cylinder 44 is extended so that the air pressure does not occur and the exhaust pressure that does not promote the entry of outside air is applied to the chamber 11. is there.
[0030]
In addition, when the opening 12 is opened, nitrogen gas or the like is supplied from the gas supply unit 20 to the chamber 11 in order to prevent the outside air from entering. Since the flow rate is made very small, the supplied gas is hardly exhausted unnecessarily, and the entrainment of outside air can be prevented and the gas consumption can be reduced.
[0031]
Next, when the loading of the substrate W is completed and the loading / unloading robot is retracted, the gate valve 13 closes the opening 12 and gas replacement is performed. In the gas replacement, a processing gas (for example, an inert gas such as nitrogen gas or an active gas such as ammonia gas) necessary for forming a processing atmosphere of the substrate W from the gas supply unit 20 while exhausting from the gas exhausting unit 30 is used. Gas or the like) is supplied to the chamber 11. At this stage, the exhaust pressure switching unit 40 takes the state shown in FIG. 3, that is, the piston 45 is contracted. Therefore, the exhaust pressure with respect to the chamber 11 becomes a large exhaust pressure, and a large flow rate is exhausted from the chamber 11. The gas exhausted from the chamber 11 flows as indicated by arrows A30, A31, A32 and is exhausted to the exhaust line. At this time, even if the pressure in the exhaust line fluctuates, the fluctuation is absorbed by the spring 46 and flattened, so that a large exhaust pressure can be stably applied to the chamber 11.
[0032]
Since the exhaust pressure acting on the chamber 11 is as large as the negative pressure of the exhaust line, positive exhaust can be performed using the exhaust force. Therefore, the replacement efficiency of gas replacement is high, and the time required for gas replacement can be shortened.
[0033]
When the gas replacement is completed, a heat treatment is performed by irradiating light from the lamp. Further, after the heat treatment is completed, the gate valve 13 opens the opening 12 again, and the loading / unloading robot unloads the substrate W from the chamber 11. When an atmosphere of an active gas such as ammonia is formed for the heat treatment of the substrate W, it is necessary to replace the active gas with an inert gas such as nitrogen gas before opening the opening 12. is there. Also in this case, gas replacement can be performed efficiently by setting the exhaust pressure switching unit 40 to the state shown in FIG. 3 and supplying a large exhaust force to the chamber 11. When the opening 12 is opened, the exhaust pressure switching unit 40 is brought into the state shown in FIG. 2 again, and a minute exhaust force is supplied to the chamber 11 to prevent the air from staying in the chamber 11. In addition, it is possible to prevent the outside air from entering.
[0034]
As described above, the substrate processing apparatus 10 of this embodiment appropriately switches the exhaust pressure for the chamber 11 by the exhaust pressure switching unit 40 using the cylinder 44. That is, when the opening 12 is opened, the exhaust pressure with respect to the chamber 11 is set to a small exhaust pressure, and when the opening 12 is closed and gas is supplied from the gas supply unit 20 to the chamber 11, the exhaust pressure with respect to the chamber 11 is set. By using a large exhaust pressure, both prevention of outside air entrapment and efficient gas replacement are achieved.
[0035]
Here, since the gas pressure type cylinder 44 functions as a driving source for switching the exhaust pressure, the exhaust pressure for the chamber 11 can be managed only at two points of the large exhaust pressure and the small exhaust pressure. The atmospheric pressure and the small exhaust pressure can be switched in a short time. In other words, the switching time is shortened as a price that allows only simple switching of the exhaust pressure to the chamber 11 at only two points.
[0036]
As described above, since the substrate processing apparatus 10 of the present embodiment switches the exhaust pressure for the chamber 11 to only two points of the large exhaust pressure and the small exhaust pressure, the switching time is shortened, and the switching operation is performed in the chamber. Therefore, it is possible to appropriately follow the open / close state of 11 (strictly speaking, the open / close state of the opening 12 of the chamber 11). That is, the exhaust force supplied to the chamber 11 can be quickly changed according to the open / closed state of the chamber 11. In particular, in the single wafer type light irradiation type heat treatment apparatus as in the present embodiment, the processing time of the substrate W is short, and the open / close state of the chamber 11 changes in a short time. Is big. In order to shorten the switching time of the exhaust pressure, the shorter the operation time of the cylinder 44 is, the better it is within 1 second, but it is possible to put it into practical use within 3 seconds.
[0037]
While the embodiments of the present invention have been described above, the present invention is not limited to the above examples. For example, in the above embodiment, an exhaust pressure regulator capable of controlling the exhaust force at any two points is used as the exhaust pressure switching unit 40. However, the present invention is not limited to this, and the form shown in FIG. Also good. FIG. 4 is a diagram illustrating another example of the configuration of the exhaust pressure switching unit 40. The exhaust pressure switching unit 40 in FIG. 4 includes a needle valve 51 and a bypass valve 52. The bypass valve 52 is an air valve that is driven by air, and can adopt only two modes of fully open and fully closed. Further, the needle valve 51 is fixedly set so that the flow rate that can be passed is very small.
[0038]
The exhaust pressure switching unit 40 fully closes the bypass valve 52 when the opening 12 is open. Therefore, the exhaust force supplied from the exhaust line to the chamber 11 is very small only through the needle valve 51, and the exhaust pressure with respect to the chamber 11 becomes a small exhaust pressure as in the above embodiment.
[0039]
On the other hand, when the opening 12 is closed, the bypass valve 52 is fully opened. As a result, the exhaust force supplied from the exhaust line to the chamber 11 mainly becomes large via the bypass valve 52, and the exhaust pressure with respect to the chamber 11 becomes a large exhaust pressure as in the above embodiment.
[0040]
Even in this case, similarly to the exhaust pressure switching unit 40 of FIGS. 2 and 3, by appropriately switching the exhaust pressure with respect to the chamber 11, it is possible to achieve both prevention of outside air entrainment and efficient gas replacement. Since the air-driven bypass valve 52 that can take only two modes of fully open and fully closed functions as a drive source for switching the exhaust pressure with respect to the chamber 11, as in the above-described embodiment. The switching time of the atmospheric pressure is shortened, and the switching operation can appropriately follow the open / close state of the chamber 11.
[0041]
Moreover, although the substrate processing apparatus 10 of the said embodiment was a light irradiation type heat processing apparatus, it is not restricted to this, The technique which concerns on this invention is applicable if it is a substrate processing apparatus which switches an exhaust pressure.
[0042]
【The invention's effect】
As described above, according to the present invention, when the gas pressure type cylinder opens the substrate during loading / unloading of the substrate, the exhaust pressure with respect to the chamber is set to a small exhaust pressure, and when the gas in the chamber is replaced. When the opening is closed and gas is supplied from the gas supply means to the chamber, the exhaust pressure for the chamber is set to a large exhaust pressure larger than the small exhaust pressure, so the exhaust force supplied to the chamber is While changing quickly according to the open / close state of the chamber, it is possible to achieve both prevention of outside air entrainment into the chamber when the opening is released and efficient gas replacement when the opening is closed.
[Brief description of the drawings]
FIG. 1 is a conceptual diagram showing a configuration of a substrate processing apparatus according to the present invention.
2 is a diagram illustrating an example of a configuration of an exhaust pressure switching unit of the substrate processing apparatus of FIG. 1;
3 is a diagram showing an example of a configuration of an exhaust pressure switching unit of the substrate processing apparatus of FIG. 1;
4 is a diagram showing another example of the configuration of the exhaust pressure switching unit of the substrate processing apparatus of FIG. 1. FIG.
FIG. 5 is a diagram showing a schematic configuration of an example of a conventional substrate processing apparatus.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 10 Substrate processing apparatus 11 Chamber 12 Opening part 13 Gate valve 20 Gas supply part 30 Gas exhaust part 31 Exhaust pipe 40 Exhaust pressure switching part 44 Cylinder 51 Needle valve 52 Bypass valve W Substrate

Claims (2)

A substrate processing apparatus for performing predetermined processing on a substrate,
A chamber for forming a processing space for performing the processing on the substrate and an opening for carrying the substrate in and out;
An opening and closing means for opening and closing the opening;
An exhaust path coupled to the chamber for supplying exhaust force to the chamber;
A gas pressure type cylinder provided in the exhaust path and switching an exhaust pressure to the chamber;
Gas supply means for supplying gas to the chamber;
With
The gas pressure cylinder is
When the opening is opened during loading / unloading of the substrate, the exhaust pressure with respect to the chamber is set to a small exhaust pressure, and when the gas in the chamber is replaced, the opening is closed and gas is supplied from the gas supply means to the chamber. When being performed, the substrate processing apparatus is characterized in that the exhaust pressure with respect to the chamber is set to a large exhaust pressure larger than the small exhaust pressure. The substrate processing apparatus according to claim 1,
2. The substrate processing apparatus according to claim 1, wherein the gas replacement in the chamber is performed after the substrate is loaded.

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