JP2000100742A - Heat treatment apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a heat treatment apparatus which can maintain an in-plane uniformity of a substrate temperature at heat treatment. SOLUTION: This apparatus includes a first gas inlet port 80 provided at a position facing an opening 11 of a chamber 10, and a second gas inlet port 90 for introducing a gas into the chamber 10 through a plurality of gas blow-out ports 91 made in a plate provided nearly parallel to the plane of a substrate W within the chamber 10. By providing a gas exhaust port 70 in a furnace block 50, when a gas is introduced from the first gas inlet port 80 during carry-in and out of the substrate W, outside air can be efficiently prevented from being included into the chamber 10, even if the furnace port is opened. At heat treatment, by introducing a gas into the chamber 10 from the second gas inlet port 90, a gas flow which is nearly vertical to the substrate plane is established, thus enabling maintenance of an in-plane uniformity of a substrate temperature.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a semiconductor wafer, a glass substrate for a liquid crystal display, a glass substrate for a photomask,
The present invention relates to a heat treatment apparatus for performing a heat treatment on an optical disk substrate or the like (hereinafter, referred to as a “substrate”).

[0002]

2. Description of the Related Art In recent years, in a substrate processing step, a single wafer type heat treatment apparatus has been widely used in a plurality of steps instead of a batch type electric furnace. FIG. 7 is a diagram showing a heat treatment apparatus conventionally used. 7A is a schematic side sectional view of a conventional heat treatment apparatus, and FIG. 7B is a schematic view of the AA cross section of FIG. 7A viewed from the moving flange 30 side. Hereinafter, the conventional heat treatment apparatus shown in FIG.

The moving flange 30 is movable in a direction indicated by an arrow X. A susceptor 35 is fixed to the moving flange 30, and the susceptor 35 is configured to support the substrate W. Then, the arrow X of the moving flange 30
With the movement in the direction indicated by, the substrate W supported by the susceptor 35 moves in and out of the chamber 10.

The chamber 10 is made of a material having a property of transmitting light (such as quartz). Also, chamber 1
At 0, a furnace port block 50 is fixed. When the moving flange 30 moves to the chamber 10 side and comes into contact with the furnace port block 50, the furnace port serving as an opening for loading and unloading the substrate W is closed, and the substrate W is
Is held in a predetermined position. Then, by performing light irradiation from the lamp 20 in this state, the heat treatment of the substrate W is performed.

During the heat treatment of the substrate W, the substrate W
A high-purity gas (for example, a nitrogen gas or the like) is flown into the chamber 10 so as to bring the surrounding area into a predetermined atmosphere state. The gas is introduced from a gas introduction port 60 provided at a position facing the furnace port of the chamber 10, and is exhausted from a gas exhaust port 70. When the gas inlet 60 is viewed from the inside of the chamber 10,
As shown in FIG. 7 (b), a plurality of outlets 61 having substantially the same size are formed.
The gas is uniformly introduced into the chamber 10 from above. Accordingly, FIG.
In (a), a gas flow is formed in the right direction.

When the heating process is completed, the substrate W is cooled to a predetermined temperature in the chamber 10, and then the moving flange 30 moves in the opposite direction to the chamber 10, and
Is carried out of the apparatus.

In such a conventional heat treatment apparatus,
Since the gas introduction port 60 and the gas exhaust port 70 are provided so that the gas flow formed in the chamber 10 is directed to the furnace port side, even if the furnace port is opened when the substrate W is carried in and out, the gas port is opened. In addition to a configuration that can effectively prevent outside air from entering the chamber 10, efficient gas replacement can be performed even when gas replacement within the chamber 10 is performed during substrate processing. It can be configured.

[0008]

It is very important to maintain the in-plane uniformity of the temperature of the substrate W during the heat treatment of the substrate W. This is because, if the in-plane temperature distribution during the heat treatment of the substrate W is not uniform, distortion due to the temperature difference occurs in the plane of the substrate W, and a slip line is generated.

However, in the above-described conventional apparatus, when a gas flow is formed from the gas inlet 60 toward the furnace port during the heat treatment of the substrate W, the temperature gradient of the substrate W is increased in the direction of the gas flow. Was to occur.
That is, the gas inlet 60 side of the substrate W has a relatively low temperature, and the furnace port side of the substrate W has a relatively high temperature.
There has been a problem that uniform processing cannot be performed on the substrate W. In particular, the temperature near the end of the substrate closer to the gas inlet 60 is extremely lower than that of the other portions.
This is also a factor that deteriorates the temperature distribution of the substrate W.

[0010] The present invention has been made in view of the above problems, and has as its object to provide a heat treatment apparatus capable of maintaining in-plane uniformity of a substrate temperature during heat treatment.

[0011]

According to a first aspect of the present invention, there is provided a heat treatment apparatus for performing a heat treatment of a substrate, the method comprising: (a) a process in which an opening for carrying in and out a substrate is formed; A first chamber for introducing a predetermined gas into the processing chamber, the first chamber being provided at a position facing the opening of the processing chamber;
And (c) a second gas inlet for introducing a predetermined gas into the processing chamber from a plurality of gas outlets formed in a plane substantially parallel to the surface of the substrate housed in the processing chamber. And (d) a gas exhaust port that is provided closer to the opening than the substrate housed in the processing chamber and exhausts gas introduced into the processing chamber to the outside of the processing chamber.

According to a second aspect of the present invention, in the heat treatment apparatus of the first aspect, when the substrate is carried in and out of the processing chamber,
The amount of gas introduced from the first gas inlet is controlled to be greater than the amount of gas introduced from the second gas inlet.

According to a third aspect of the present invention, in the heat treatment apparatus of the second aspect, when the substrate is carried in and out of the processing chamber,
A gas is introduced into the processing chamber only from the first gas inlet.

According to a fourth aspect of the present invention, in the heat treatment apparatus according to any one of the first to third aspects, when performing a heat treatment on the substrate, the amount of gas introduced from the second gas introduction port is reduced. , And is controlled to be larger than the amount of gas introduced from the first gas inlet.

According to a fifth aspect of the present invention, in the heat treatment apparatus of the fourth aspect, a gas is introduced into the processing chamber only from the second gas introduction port when performing the heat treatment on the substrate. I have.

According to a sixth aspect of the present invention, in the heat treatment apparatus according to any one of the first to fifth aspects, when replacing the gas in the processing chamber, the first gas inlet and the second gas inlet are connected to each other. The gas is introduced from both of the gas inlets.

[0017]

FIG. 1 is a view showing a heat treatment apparatus according to an embodiment of the present invention. FIG. 1A is a schematic side sectional view of a heat treatment apparatus according to this embodiment,
(B) is a schematic diagram of the AA cross section of (a) viewed from the moving flange 30 side.

Inside the furnace wall 55, a chamber 10 serving as a processing chamber for processing a substrate W and a plurality of lamps 20 are provided. An opening 11 for loading and unloading the substrate W is formed in the chamber 10.
A furnace port block 50 is provided on the side. An opening 51 is also formed in the furnace opening block 50 at a position corresponding to the opening 11 of the chamber 10, and the opening 11 of the chamber 10 and the opening 51 of the furnace opening block 50 form a furnace opening. ing. As the lamp 20 serving as a heat source, an infrared lamp, a halogen lamp, a xenon arc lamp, or the like is used. The chamber 10 is made of a material having a property of transmitting light (quartz or the like), and transmits light emitted from the lamp 20 to the inside thereof. An O-ring 55a and an O-ring 50b are provided at connection portions of the chamber 10, the furnace wall 55, and the furnace port block 50, respectively, so that the inside of the chamber 10 can be kept airtight. The furnace wall 55 and the inner portion of the furnace port block 50 facing the chamber 10 are configured to be mirror-polished or the like so as to reflect light from the lamp 20 efficiently.

A susceptor 35 is fixed to the moving flange 30. The susceptor 35 has three support pins 36.
(Only two are shown in the side view of FIG. 1A), and the substrate W to be processed is supported by the support pins 36 in a substantially horizontal posture.

The moving flange 30 is moved horizontally (FIG. 1).
(The direction indicated by arrow X in (a)). Since the susceptor 35 fixed to the moving flange 30 supports the substrate W, the substrate W also moves in the direction indicated by the arrow X as the moving flange 30 moves. That is, the susceptor 35 fixed to the movable flange 30 is configured to enter and exit the inside of the chamber 10 while supporting the substrate W, and thereby carry the substrate W into and out of the chamber 10. It is.

When the moving flange 30 moves toward the chamber 10 and abuts on the furnace port block 50, the furnace port for carrying in and out the substrate W is closed, and the substrate W
It is stored and held at a predetermined position within 0. Then, by performing light irradiation from the lamp 20 in this state, the heat treatment of the substrate W is performed. The furnace opening block 50 is provided with an O-ring 50a.
Is in contact with the furnace port block 50, the O-ring 50a maintains the airtightness inside the chamber 10.

On the other hand, when the moving flange 30 moves to the opposite side of the chamber 10, the furnace port is opened, and the moving flange 30 further moves to move the substrate W into the chamber 10.
And it is drawn out of the furnace opening block 50. In this state, the transfer of the substrate W (replacement of the unprocessed substrate W and the processed substrate W) is performed between the substrate transfer robot (not shown) and the susceptor 35 outside the apparatus.

As described above, during the heat treatment of the substrate W,
The surroundings of the substrate W need to be in a predetermined atmosphere state. Therefore, the heat treatment apparatus of this embodiment is provided with a first gas inlet 80, a second gas inlet 90, and a gas outlet 70.

A gas exhaust port 70 is formed in the furnace port block 50, and exhausts gas introduced from the first gas inlet 80 or the second gas inlet 90 to the outside of the apparatus.

The first gas inlet 80 is provided on the side of the chamber 10 facing the opening 11. Therefore, when the gas is introduced into the chamber 10 from the first gas inlet 80, a gas flow is formed rightward along the surface of the substrate W in FIG. The first gas inlet 80 is formed to penetrate the furnace wall 55 and the end of the chamber 10, and is connected to gas supply means outside the apparatus via a first opening / closing valve described later. When the first gas inlet 80 is viewed from the inside of the chamber 10, FIG.
As shown in FIG. 3, a plurality of outlets 81 having substantially the same size are formed, and the gas is uniformly introduced into the chamber 10 from the plurality of outlets 81.

The second gas inlet 90 is connected to the chamber 1
0 is provided on the upper side. When the gas is introduced from the second gas inlet 90, a downward gas flow substantially perpendicular to the substrate surface is formed from the plurality of gas outlets 91 formed above the substrate W in the chamber 10. It is configured as follows. Here, FIG. 2A is a side view showing only the chamber 10 of the heat treatment apparatus of FIG. 1, and FIG. 2B is a plan view showing an example of a plurality of outlets 91. FIG.
In FIG. 2B, a circular dotted line is a virtual line indicating the outer shape of the substrate W accommodated in the chamber 10. As described above, the plurality of outlets 91 are arranged and formed so as to blow out the gas toward the entire surface of the substrate W. Therefore, when the gas is introduced from the second gas inlet 90, the outlet 91 is directed downward substantially perpendicular to the substrate surface. The gas flow is formed uniformly on the substrate W. The second gas inlet 90 is also formed through the furnace wall 55 and the end of the chamber 10 and communicates with a gas supply means outside the apparatus via a second opening / closing valve described later. I have.

Next, FIG. 3 is a schematic view showing a mechanism for controlling gas introduction into the chamber 10. As shown in FIG. The first opening / closing valve 83 is connected to the first gas inlet 80,
A second opening / closing valve 93 is connected to the gas introduction port 90 of the second embodiment. Therefore, gas introduction from the first gas inlet 80 is performed by opening the first opening / closing valve 83, and gas introduction from the second gas inlet 90 is performed by opening the second opening / closing valve 93. Will be As described above, the upstream side of the first and second opening / closing valves 83 and 93 communicates with the gas supply means outside the apparatus, and when a plurality of types of gases are supplied into the chamber 10, a plurality of gas supply means are provided. Is in communication with Further, a main control unit 3, a storage unit 4, and a valve control unit 5 are provided as a control mechanism for automatically opening and closing the first and second opening / closing valves 83, 93.

The storage unit 4 stores recipe data indicating a processing procedure for the substrate W and the like.
Reads the recipe data and performs overall control of the substrate processing based on the recipe data. Then, the main control unit 3 sends an opening / closing command for the first opening / closing valve 83 and the second opening / closing valve 93 to the valve control unit 5 at a predetermined timing in the course of the substrate processing. The valve control unit 5 is configured to individually open and close the first opening and closing valve 83 and the second opening and closing valve 93 in response to the opening and closing command. The main control unit 3 is also connected to a not-shown lamp control unit, a substrate transfer robot, and the like, and also controls these components.

In the heat treatment apparatus configured as described above, if the gas is introduced from the first gas inlet 80 when the furnace port is opened when the substrate W is loaded and unloaded, the outside air can be reduced. Mixing into the chamber 10 can be efficiently prevented, and when the substrate W is subjected to heat treatment, if the gas is introduced from the second gas inlet 90, a temperature gradient of the substrate W occurs. This makes it possible to perform a uniform process on the substrate W without performing any process.

In the following, a gas introduction procedure for obtaining such an effect will be described with reference to a specific substrate processing procedure. In the following, the first control is automatically performed by the above-described control mechanism with the progress of the substrate processing.
The opening / closing operation of the opening / closing valve 83 and the second opening / closing valve 93 is performed.

FIG. 4 is a diagram showing an example of a procedure when a predetermined gas (for example, oxygen gas) is supplied during the processing of the substrate W. Note that the procedure in FIG. 4 is an example of a heat treatment for forming an oxide film on the substrate surface.

At time Ta1, the operation of loading the substrate W into the chamber 10 is started. At this time, since the furnace port is opened, it is necessary to efficiently prevent outside air from entering the chamber 10. Therefore, only the first opening / closing valve 83 provided for the first gas inlet 80 is opened,
The second opening / closing valve 93 provided for the second gas inlet 90 is closed. By doing so, a gas flow is formed rightward from the first gas inlet 80 toward the furnace port in FIG. 1A, so that the outside air can be efficiently prevented from being mixed into the chamber 10. .
At this time, the type of gas supplied from the gas supply means is nitrogen gas, which is an inert gas.

When the sealing in the chamber 10 is completed, gas replacement for replacing the gas in the chamber 10 from nitrogen gas to oxygen gas at time Ta2 is started. Chamber 10
When replacing the gas in the chamber, the gas is introduced from both the first gas inlet 80 and the second gas inlet 90 to perform the gas replacement in the chamber 10.

For example, in the chamber 10 shown in FIG. 3, a space R having a predetermined capacity is provided between the upper wall portion 13 of the chamber 10 and the blowing plate 14 having a plurality of blowing ports 91 formed therein.
Is formed. Therefore, at the time of gas replacement, this space R
Since it is necessary to replace the gas accumulated in the gas, the gas is also introduced from the second gas inlet 90.
At the same time, by introducing a gas from the first gas inlet 80, the gas in the chamber 10 can be efficiently replaced.

At this time, the type of gas supplied from the gas supply means is oxygen gas, and the gas in the chamber 10 is replaced from nitrogen gas to oxygen gas in about 20 seconds.

When the gas replacement is completed, the time Ta
3, power is supplied to the lamp 20, and the process of increasing the temperature of the substrate W is started. At this time, in order to prevent a temperature gradient from occurring in the substrate W, the first opening / closing valve 83 is closed and only the second opening / closing valve 93 is opened, and gas is introduced only from the second gas inlet. This allows the chamber 10
The gas flow formed therein is directed downward perpendicular to the substrate W, and a uniform gas flow is formed over the entire surface of the substrate W.
The occurrence of a temperature gradient in the substrate W can be prevented.

The substrate W is heated to a predetermined temperature (400 ° C.
When the temperature rises to about 1100 ° C.), holding heating is performed from time Ta4 to hold the temperature for a certain period of time (for example, 60 seconds). In order to prevent a temperature gradient from occurring in the substrate W even during the holding and heating, gas is introduced only from the second gas introduction port. During this process, an oxide film is formed on the substrate surface.

Then, after a lapse of a predetermined time, at time Ta
From step 5, the substrate W is naturally cooled. That is, the lamp 20 is turned off, and the process stands by until the inside of the chamber 10 decreases to a certain temperature. At this time, the first gas inlet 80 and the second
Nitrogen gas, which is an inert gas, is introduced from both the gas inlet 90 and the gas inlet 90, and the gas in the chamber 10 is replaced. Note that, depending on the processing mode of the substrate W, the second gas inlet 90 may be closed during the natural cooling.

When the temperature in the chamber 10 drops to a certain temperature, the moving flange 30 moves at a time Ta6, and the unloading operation of the substrate W starts. At this time, since the furnace port is opened, it is necessary to efficiently prevent outside air from entering the chamber 10. Therefore, nitrogen gas is introduced only from the first gas inlet 80.

The heating process for one substrate W is performed as described above, and the heating process is performed for a plurality of substrates W by repeating the above process.

As described above, in the heat treatment apparatus of this embodiment, the first gas inlet provided at a position facing the opening 11 of the chamber 10 and the chamber 1
And a second gas inlet for introducing gas into the chamber 10 from a plurality of gas outlets formed in a plane substantially parallel to the substrate surface accommodated in the gas outlet 7.
0 is formed in the furnace port block 50, so that even if the furnace port is opened when loading and unloading the substrate W, it is possible to efficiently prevent outside air from entering the chamber 10. In addition, the configuration is such that the in-plane uniformity of the substrate temperature during the heat treatment can be maintained.

The present invention is not limited to the above example. For example, in the above embodiment, the first gas inlet 80 and the second gas inlet 90
Are shown as being integrally formed, but the present invention is not limited to this. For example, the second gas inlet 9
There is no problem even if the zero part is configured separately from the chamber 10. FIG. 5 and FIG. 6 are schematic diagrams showing such a configuration example.

In the chamber 10 shown in FIG. 5A, a second gas introduction member 15 serving as a second gas introduction port is formed as a separate body, and the second gas introduction member 15 is formed inside the chamber 10. By being supported by the support member 12, a processing chamber having the same configuration as described above can be formed. On the lower surface side of the second gas introduction member 15, a plurality of outlets 91 are formed as shown in FIG. 5B. The formation pattern of the outlet 91 may be a radial pattern as shown in FIG. 2B, or may be a matrix pattern as shown in FIG. 5C. Further, other patterns may be used, but it is preferable to arrange them so as to be distributed over a wider range than the outer shape of the substrate W.

Also in FIG. 6A, a second gas introduction member 16 serving as a second gas introduction port is formed separately from the chamber 10, and the second gas introduction member 16 has a plurality of legs 16a. Is provided. In this case, since the second gas introducing member 16 is supported by the plurality of legs 16a, the supporting member 1 is provided in the chamber 10 as compared with the one shown in FIG.
2 need not be formed. FIG. 6B shows a schematic side view of the second gas introduction member 16, and FIG. 6C shows a schematic plan view seen from below. In the case of forming the second gas introduction member 16 as shown in FIG.
It is preferable that a is formed at a position that does not hinder the transfer of the substrate W or the gas flow. In this case, the outlet 9
The formation pattern of No. 1 is the same as above.

In the above embodiment, the gas introduction performed by the first gas introduction port 80 and the gas introduction performed by the second gas introduction port 90 are switched between the first and second opening / closing valves 83 and 93. Although the case of opening and closing control has been described, the present invention is not limited to this. For example, when carrying the substrate W into and out of the chamber 10, the amount of gas introduced from the first gas inlet is controlled to be greater than the amount of gas introduced from the second gas inlet. You may do so. This is because, even if the furnace port is opened in FIG. 1A, when the amount of gas introduced from the first gas inlet 80 is large, the main gas flow is from the first gas inlet 80 to the furnace port side. This is because it is formed to the right toward, so that the intrusion of outside air into the chamber 10 can be reduced.

Further, for example, during the heat treatment of the substrate W, the amount of gas introduced from the second
May be controlled so as to be larger than the gas amount introduced from the gas inlet. Because Figure 1
In (a), when a large amount of gas is introduced from the second gas inlet 90 during the heat treatment of the substrate W, the main gas flow is formed downward from the plurality of outlets 91 toward the substrate W. This is because it is possible to reduce the temperature gradient generated in the substrate W.

[0047]

As described above, according to the first aspect of the present invention, when a gas is introduced from the first gas inlet into the processing chamber, a gas flow is formed toward the opening substantially parallel to the substrate surface. When a gas is introduced into the processing chamber from the second gas inlet, a gas flow that is substantially perpendicular to the substrate surface is formed, so that it is possible to prevent outside air from being mixed into the processing chamber when loading and unloading the substrate. The configuration is such that the in-plane uniformity of the substrate temperature during the heat treatment can be maintained.

According to the second aspect of the present invention, when the substrate is carried into and out of the processing chamber, the amount of gas introduced from the first gas inlet is smaller than the amount of gas introduced from the second gas inlet. Is also controlled to be large, so that the intrusion of outside air into the processing chamber can be reduced.

According to the third aspect of the present invention, when a substrate is carried into or out of the processing chamber, gas is introduced into the processing chamber only from the first gas inlet, so that outside air can be efficiently mixed into the processing chamber. Can be prevented.

According to the fourth aspect of the present invention, when performing the heat treatment on the substrate, the amount of gas introduced from the second gas inlet is larger than the amount of gas introduced from the first gas inlet. Therefore, the temperature gradient generated in the substrate can be reduced.

According to the fifth aspect of the present invention, when performing the heat treatment on the substrate, the gas is introduced into the processing chamber only from the second gas inlet, so that the in-plane uniformity of the substrate temperature during the heat treatment is improved. It can be maintained well.

According to the invention of claim 6, when replacing the gas in the processing chamber, the gas is introduced from both the first gas introduction port and the second gas introduction port. In addition, gas replacement can be performed efficiently and favorably.

[Brief description of the drawings]

FIG. 1 is a diagram showing a heat treatment apparatus according to an embodiment of the present invention.

FIG. 2 is a diagram showing a chamber of a heat treatment apparatus.

FIG. 3 is a schematic diagram showing a mechanism for controlling gas introduction into a chamber.

FIG. 4 is a diagram illustrating an example of a procedure when one type of gas (for example, oxygen gas) is supplied during processing of a substrate.

FIG. 5 is a schematic view showing a modification of the chamber configuration.

FIG. 6 is a schematic diagram showing a modification of the chamber configuration.

FIG. 7 is a view showing a heat treatment apparatus conventionally used.

[Explanation of symbols]

 Reference Signs List 3 Main control unit 5 Valve control unit 10 Chamber 20 Lamp 30 Moving flange 35 Susceptor 50 Furnace block 70 Gas exhaust port 80 First gas inlet 83 First open / close valve 90 Second gas inlet 91 Outlet 93 2 opening / closing valve W board

Claims (6)

[Claims] 1. A heat treatment apparatus for performing a heat treatment of a substrate, comprising: (a) a processing chamber having an opening through which a substrate is carried in and out; and (b) a processing chamber having a position facing the opening. A first gas inlet provided to introduce a predetermined gas into the processing chamber; and (c) a plurality of gas outlets formed in a plane substantially parallel to a substrate surface accommodated in the processing chamber. A second gas introduction port for introducing a predetermined gas into the processing chamber; and (d) a gas provided in the opening side of a substrate housed in the processing chamber, and the gas introduced into the processing chamber is supplied to the processing chamber. And a gas exhaust port for exhausting the gas to the outside of the heat treatment apparatus. 2. The heat treatment apparatus according to claim 1, wherein the amount of gas introduced from the first gas inlet when transferring the substrate into and out of the processing chamber is greater than the amount of gas introduced from the second gas inlet. A heat treatment apparatus characterized in that the heat treatment apparatus is controlled so as to be larger than an introduced gas amount. 3. The heat treatment apparatus according to claim 2, wherein a gas is introduced into the processing chamber only from the first gas inlet when the substrate is carried into and out of the processing chamber. apparatus. 4. The heat treatment apparatus according to claim 1, wherein the amount of gas introduced from the second gas introduction port when performing heat treatment on the substrate is the first gas introduction amount. A heat treatment apparatus characterized in that the heat treatment apparatus is controlled so as to be larger than a gas amount introduced from a gas inlet. 5. The heat treatment apparatus according to claim 4, wherein a gas is introduced into the processing chamber only from the second gas introduction port when performing the heat treatment on the substrate. 6. The heat treatment apparatus according to claim 1, wherein when replacing the gas in the processing chamber, the first gas inlet and the second gas inlet are connected to each other. Wherein the gas is introduced from both.