JP2000012478A - Heat treatment system for substrate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a heat treatment system for substrate in which processing gas is prevented from touching a substrate under temperature rise to accelerate generation of a defect in the substrate through heat shock or touching a temperature raised substrate to deteriorate temperature distribution in the plane of the substrate so that uniform heat treatment can be ensured. SOLUTION: An induction heating gas heater 28 is provided in a passage 16 for supplying processing gas into a heat treatment furnace 10. The induction heating gas heater 28 is constructed by winding a coil 32 around the outer surface of an enclosed container 30 made of a nonmagnetic material and disposing a heater 32 made of a conductive material in the container 30.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for irradiating a substrate in a heat treatment furnace with a substrate, such as a lamp anneal apparatus or a CVD apparatus. The present invention relates to a substrate heat treatment apparatus for performing heat treatment such as annealing, oxynitriding, and film formation on a substrate by heating the substrate by heating.

[0002]

2. Description of the Related Art In a substrate heat treatment apparatus of this type, for example, a lamp annealing apparatus, substrates are carried one by one through openings into a heat treatment furnace formed flat by quartz glass or the like, and the openings are closed. An active or inert gas such as oxygen, nitrogen, argon, ammonia, or nitric oxide is supplied from a supply unit into the heat treatment furnace, and the substrate accommodated in the heat treatment furnace is heated by light irradiation to heat the substrate. Like that. FIG. 7 shows an example of a schematic configuration of a conventional lamp annealing apparatus.

The heat treatment furnace 10 is formed in a flat shape from quartz glass or the like, and although not shown, has an opening for carrying in and out the substrate W, and can be hermetically closed by closing the opening. It is. The heat treatment furnace 10 has a gas supply port 12 and a gas discharge port 14 formed therein.
A gas supply path 16 connected to a gas supply unit (not shown) communicates with the gas supply port 12.
A mass flow controller (MFC) 18 and an electromagnetic on-off valve 20 are provided therebetween. The substrate W is supported by a plurality of points, for example, four points by the susceptor 22 one by one,
It is carried into the heat treatment furnace 10 and is kept in a horizontal posture during the heat treatment and is carried out of the heat treatment furnace 10. Outside the heat treatment furnace 10, a plurality of lamp heaters 24 for heating the substrate are arranged in line near the upper wall surface of the heat treatment furnace 10, and a water-cooled reflecting plate is provided on the rear side (upper side) of the lamp heater 24. 26 are provided.

As shown in FIG. 8, a gas flow path 2 is formed in a part of the heat treatment furnace 1, and one end of the gas flow path 2 is communicated with a gas supply path 16 as a gas supply port 3, Road 2
The other end of the heat treatment furnace 1 is opened at one end as a gas outlet 4 inside the heat treatment furnace 1, and the other end of the heat treatment furnace 1 (gas supply port 3
There is also a lamp annealing apparatus in which a gas outlet 5 is provided on the side where (a) is formed. In the apparatus having such a configuration, the processing gas supplied from the gas supply unit to the heat treatment furnace 1 through the gas supply path 16 flows through the gas flow path 2 while radiating heat from the lamp heater 24 and processing the substrate W. It is heated by convective heat transfer from the space and supplied to the surface of the substrate W in a state of being preheated to some extent.

[0005]

In a conventional lamp annealing apparatus as shown in FIG. 7, a substrate W accommodated in a heat treatment furnace 10 is heated by a lamp heater 24 so that the substrate W
While the temperature is rising, a low-temperature processing gas is supplied into the heat treatment furnace 10. Then, the low-temperature gas comes into contact with the substrate W during the temperature rise. As a result, thermal shock is applied to the substrate W, and in the worst case, slip (crystal defects of the thin film)
And other defects. Further, regarding the substrate W after the temperature rise, the substrate W
At this time, there is a problem that a portion closer to the gas supply port 12 is cooled and the temperature is lowered, so that the temperature distribution in the plane of the substrate W is deteriorated and a uniform heat treatment cannot be performed. Was.

In the lamp annealing apparatus having the structure shown in FIG. 8, the processing gas supplied to the heat treatment furnace 1 is:
Since it is heated while flowing in the gas flow path 2 and supplied to the surface of the substrate W in a state of being preheated to some extent,
The processing gas has less influence on the substrate W as compared with the apparatus shown in FIG. However, the temperature of the processing gas does not rise so much due to the radiant heat transfer from the lamp heater 24, and the convection heat transfer from the processing space of the substrate W does not have a large heat transfer area, so the temperature rises. Will be insufficient. As a result, there remains a problem that the substrate W after the temperature is raised is cooled by the low-temperature processing gas, and the temperature distribution in the surface of the substrate W is deteriorated, so that a uniform heat treatment cannot be performed.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and promotes the generation of defects in a substrate when a processing gas is brought into contact with the substrate being heated, or the substrate after being heated. It is an object of the present invention to provide a substrate heat treatment apparatus capable of preventing a temperature distribution in a substrate surface from being deteriorated due to contact of a processing gas with the substrate and making it impossible to perform uniform heat treatment.

[0008]

The invention according to claim 1 is
The processing gas is supplied into the heat treatment furnace through the gas supply path, and the substrate accommodated in the heat treatment furnace is heated by the heating means,
In a substrate heat treatment apparatus for heat-treating a substrate, an induction heating gas heater interposed in the gas supply path is provided, and the induction heating gas heater is at least partially formed of a nonmagnetic material, and has a gas inlet and a gas outlet. A container having a closed structure, a coil wound around a portion formed of a nonmagnetic material on the outer surface of the container, and a coil provided inside the container at a position corresponding to the portion around which the coil is wound; And a heating element formed of a conductive material.

According to a second aspect of the present invention, in the substrate heat treatment apparatus of the first aspect, cooling means for cooling a coil of the induction heating gas heater is additionally provided.

According to a third aspect of the present invention, in the substrate heat treatment apparatus of the first or second aspect, the gas outlet in the heat treatment furnace is opposed to the center of the substrate housed in the heat treatment furnace. A first gas supply pipe disposed therein, and a second gas supply pipe disposed so that a gas outlet in the heat treatment furnace faces a peripheral portion of a substrate housed in the heat treatment furnace, Each of the first gas supply pipe and the second gas supply pipe is connected to a gas supply path having the induction heating gas heater interposed therebetween, so that different temperatures are applied to a central portion and a peripheral portion of the substrate accommodated in the heat treatment furnace. Is supplied.

In the substrate heat treatment apparatus according to the first aspect of the present invention, the processing gas supplied into the heat treatment furnace through the gas supply passage is heated while passing through the induction heating gas heater provided in the gas supply passage. Is supplied to the heat treatment furnace in a sufficiently heated state. For this reason, even if the processing gas comes into contact with the substrate whose temperature is rising, there is no fear that a thermal shock is applied to the substrate. Also, even if the processing gas touches the substrate after the temperature rise,
Since the substrate is not cooled, there is no fear that the temperature distribution in the substrate surface is deteriorated. In the induction heating gas heater, when a high-frequency current is applied to a coil wound on the outer surface of the container, a magnetic flux is generated, and an eddy current is generated in a heating element inside the container in a magnetic field to form a heating element. Joule heat is generated due to the specific resistance of the conductive material being used, and the heating element generates heat. Therefore, the processing gas that has flowed into the container through the gas inlet is directly heated by the heating element when passing through the container. It flows out from the inside and is supplied into the heat treatment furnace.

In the substrate heat treatment apparatus according to the second aspect of the present invention, even if the coil generates heat when a high-frequency current is applied to the coil of the induction heating gas heater, the coil is cooled by the cooling means, so that the temperature of the coil is reduced. It is prevented from rising.

According to the third aspect of the present invention, the processing gas supplied through the first gas supply pipe flows out of the gas outlet toward the center of the substrate and the second gas supply pipe. The processing gas supplied through the gas flows out from the gas outlet toward the peripheral portion of the substrate. Here, the temperature of the substrate housed in the heat treatment furnace and heated by the heating means is usually higher at the center of the substrate than at the periphery of the substrate. In this device, the first
The gas supply pipe and the second gas supply pipe are connected to gas supply pipes provided with separate induction heating gas heaters, and by changing the temperature of the processing gas supplied through the respective gas supply pipes, That is, by lowering the temperature of the processing gas flowing toward the central portion of the substrate compared to the temperature of the processing gas flowing toward the peripheral portion of the substrate, the temperature of the central portion of the substrate and the temperature of the peripheral portion of the substrate are reduced. Can be made equal. As a result, the temperature uniformity in the plane of the substrate is further improved.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a preferred embodiment of the present invention will be described with reference to FIGS.

FIG. 1 is a schematic diagram showing an example of an embodiment of the present invention and showing a schematic configuration of a lamp annealing apparatus. Since the basic configuration itself such as a heat treatment furnace is not particularly different from the conventional lamp annealing apparatus shown in FIG.
The same reference numerals as those used in FIG. 7 are assigned to the respective components, and the description thereof will be omitted.

The lamp annealing apparatus includes a heat treatment furnace 1
An induction heating gas heater 28 for heating the processing gas supplied to the heat treatment furnace 10 is provided in the gas supply path 16 communicating with the gas supply port 12 of the heat treatment. The induction heating gas heater 28 is provided in the container 3 through which the processing gas flows.
0, a coil 32 wound around the container 30, a power supply 34 for supplying a high-frequency current to the coil 32, and a container 3
0 is provided with a heating element 36 disposed inside.

The container 30 has a sealed cylindrical shape as shown in FIG. 2 as an example of the configuration of the induction heating gas heater 28 in a longitudinal sectional view of a main part thereof. A port 38 and a gas outlet 40 are formed. The container 30 is formed of a non-magnetic material, for example, a plastic material such as quartz glass or a fluororesin, or a ceramic material. The entire container 30 does not necessarily need to be formed of a non-magnetic material, and it is sufficient that at least the cylindrical surface around which the coil 32 is wound is formed of a non-magnetic material. Further, the shape of the container is not limited to a cylinder, and may be various shapes.

In this embodiment, the container 30 is
The entire outer peripheral surface is covered with a water cooling jacket 42, and the coil 32 wound around the outer peripheral surface of the container 30 is sandwiched between the outer peripheral surface of the container 30 and the inner peripheral surface of the water cooling jacket 42. ing. The water-cooling jacket 42 is formed of a metal material, and has a water passage 44 having a void shape throughout the inside thereof.
Are formed. In FIG. 2, illustration of a water supply port and a drain port which are respectively connected to the water channel 44 and are connected to a water supply channel and a drain channel (not shown) is omitted.

Heating element 36 disposed inside container 30
Is held at a position corresponding to the portion where the coil 32 is wound. The heating element 36 is formed of a conductive material, for example, a high melting point metal material such as stainless steel, high melting point carbon or silicon carbide. Heating element 3
The structure of No. 6 may be any structure as long as a gas passage is secured and the contact area with the gas can be increased to some extent. For example, a plurality of thin plates are arranged in parallel with each other at intervals. 30 parallel structures along the axial direction,
A honeycomb structure or the like is employed. If the processing gas is corrosive, the outer surface of the heating element 36 may be covered with quartz or the like for protection.

The induction heating gas heater 2 configured as described above
In 8, when a high-frequency current is applied to the coil 32 by the power supply device 34, a magnetic flux is generated, an eddy current is generated in the heating element 36 inside the container 30, and Joule heat is generated in the heating element 36 due to the specific resistance of the material. Then, the heating element 36 generates heat. At this time, since the container 30 is formed of a non-magnetic material, it does not generate heat itself. When the heating element 36 generates heat, the gas supply path 16
The processing gas flowing into the container 30 through the gas inlet 38 is directly heated by heat transfer from the heating element 36 when passing through the inside of the container 30. The processing gas heated by the heat transfer from the heating element 36 and sufficiently heated,
The gas flows out of the container 30 through the gas outlet 40. At this time, when a high-frequency current is applied to the coil 32, the coil 32 itself generates heat and its temperature rises.
Further, the temperature of the outer surface of the container 30 increases due to heat transfer from the inside of the container 30, but the container 30 and the coil 32
Since the outside is covered by the water-cooling jacket 42, it is cooled by the cooling water flowing in the water passage 44 of the water-cooling jacket 42, and the temperature rise is suppressed.

The processing gas heated during passage through the induction heating gas heater 28 and sufficiently heated is supplied to the gas supply passage 16.
Through the heat treatment furnace 10. As described above, since the processing gas supplied into the heat treatment furnace 10 is sufficiently heated, even if the processing gas comes into contact with the substrate W being heated, which is accommodated in the heat treatment furnace 10, the processing gas does not touch the substrate W. There is no need to worry about thermal shock. Further, even if the processing gas comes into contact with the substrate W after the temperature rise, the substrate W is not cooled, so that there is no fear that the temperature distribution in the plane of the substrate W is deteriorated.

FIG. 3 is a longitudinal sectional view of an essential part showing another example of the configuration of the induction heating gas heater. This induction heating gas heater 4
6 is similar to the induction heating gas heater 28 shown in FIG.
A container 48 through which the processing gas flows, a coil 50 wound around the container 48, a power supply (not shown) for supplying a high-frequency current to the coil 50, and a heating element disposed inside the container 48 52, but the configuration of the container 48 is different from that shown in FIG.

That is, the container 48 of the induction heating gas heater 46 shown in FIG. 3 has a closed cylindrical shape in which a gas inlet 54 and a gas outlet 56 which are respectively connected to a gas supply passage are formed. The coil 5 inside the wall of the container 48 made of a non-magnetic material, for example, quartz glass
A gap is formed in a portion where 0 is wound, and the gap serves as a water channel 58. In the induction heating gas heater 46, when a high-frequency current flows through the coil 50, the coil 50 itself generates heat and its temperature rises.
Further, when the temperature of the outer surface of the container 48 is going to rise due to the heat transfer from the inside of the container 48, the rise of the temperature is suppressed by flowing the cooling water into the water channel 58 inside the wall surface of the container 48. The other configuration is the same as that of the induction heating gas heater 28 shown in FIG. 2, and the operation is the same. In FIG. 3, illustration of a water supply port and a drain port which are respectively connected to the water channel 58 and are connected to a water supply channel and a drain channel (not shown) is omitted.

In the induction heating gas heaters 28 and 46 shown in FIG. 2 and FIG.
It is formed in a cylindrical shape in which the inner diameter of the portion where the coils 32 and 50 are wound and the heating elements 36 and 52 are disposed is larger than the inner diameter of the gas inlets 38 and 54 and the gas outlets 40 and 56. Therefore, the processing gas introduced into the containers 30 and 48 from the gas introduction ports 38 and 54 is
It may be difficult to flow evenly toward 2. In such a case, for example, a swirl vane is attached, a baffle plate is provided, or a granular material is filled in the vicinity of the gas inlets 38, 54, and the heating elements are passed through the gas inlets 38, 54. 3
It is preferable to diffuse the gas flow toward 6, 52.

As shown in FIGS. 2 and 3, the induction heating gas heaters 28 and 46 have containers 30 and 48 in the vicinity of the gas inlets 38 and 54, the gas outlets 40 and 56, the coils 32 and 50, and the heating elements. A temperature sensor 60 is attached to each of the bodies 36 and 52, or a temperature sensor 60 is attached to one or more of them, and an induction heating gas heater is provided by a temperature controller 62 based on a detection signal from the temperature sensor 60. 28, 46 coils 32, 5
It can be configured to control the value of the current flowing to zero. In this case, when the temperature sensor 60 is attached near the gas inlets 38, 54 of the containers 30, 48,
The temperature of the processing gas passing through the induction heating gas heaters 28 and 46 is feedforward controlled by the temperature controller 62 based on the detection signal from the temperature sensor 60, and the temperature sensor 6 is disposed near the gas outlets 40 and 56 of the containers 30 and 48.
When 0 is added, the temperature of the processing gas passing through the induction heating gas heaters 28 and 46 is feedback-controlled by the temperature controller 62 based on the detection signal from the temperature sensor 60. Also, the coils 32 and 50, the heating element 36,
When the temperature sensor 60 is attached to 52, the coil 32,
Control for protecting the coils 32 and 50 and the heating elements 36 and 52 is performed so that the temperature of the heating element 50 and the heating elements 36 and 52 do not increase too much.

FIG. 4 is a schematic diagram showing one example of a control system in the lamp annealing apparatus. This lamp annealing apparatus is provided with a pyrometer 64 for measuring the temperature of the substrate W to be heat-treated, which is accommodated in the heat-treating furnace 10 without contact. Further, the lamp heater 2 is supplied from the power supply device 66.
Thyristor 6 for adjusting the amount of power supplied to 4
8, and the induction heating gas heater 28 from the power supply 34
A thyristor 70 for adjusting the amount of power supplied to the coil 32 is provided, and temperature controllers 72 and 74 for controlling the thyristors 68 and 70 based on a detection signal from the pyrometer 64 are provided respectively. Is provided. Further, a temperature sensor 76 for detecting the temperature of the processing gas supplied from the induction heating gas heater 28 to the heat treatment furnace 10 is provided in the gas supply path 16 on the outlet side of the induction heating gas heater 28. The detection signal is input to the temperature controller 74.

In the lamp annealing apparatus having the configuration shown in FIG. 4, the power controller 66 controls the thyristor 68 by the temperature controller 72 based on the detection signal from the pyrometer 64 so that the temperature of the substrate W becomes a predetermined temperature. The amount of power supplied to the lamp heater 24 from is adjusted. At the same time, by controlling the thyristor 70 with the temperature controller 74 based on the detection signal from the pyrometer 64 and the detection signal from the temperature sensor 76, the temperature of the processing gas supplied from the induction heating gas heater 28 to the heat treatment furnace 10 increases. The amount of electric power supplied from the power supply device 34 to the coil 32 of the induction heating gas heater 28 is adjusted so that the temperature of the substrate W becomes the same as the temperature of the hot substrate W.
As described above, since the temperature of the processing gas supplied into the heat treatment furnace 10 is controlled to be the same as the temperature of the substrate W being heated, even if the processing gas touches the substrate W being heated. In addition, there is no fear that a thermal shock is applied to the substrate W.

Next, the lamp annealing apparatus schematically shown in FIG. 5 includes two gas supply pipes 80 inside a heat treatment furnace 78.
a and 80b are inserted, and one gas supply pipe 80a is arranged so that its gas outlet 82a faces the center of the substrate W in the heat treatment furnace 78, and the other gas supply pipe 80b is The gas outlet 82b is arranged so as to face the peripheral portion of the substrate W. The gas outlet 84 of the heat treatment furnace 78 is formed at the bottom of the heat treatment furnace 78. One gas supply pipe 80a is connected to the low-temperature induction heating gas heater 28a, and the other gas supply pipe 80b is connected to the high-temperature induction heating gas heater 28b. Then, each induction heating gas heater 28
a, gas supply passages 86a, 86 provided with 28b interposed
6b are provided with electromagnetic on-off valves 88a, 88b and mass flow controllers 90a, 90b, respectively, and each gas supply passage 86a, 86b is provided with a gas supply unit (not shown) of the same type of processing gas. It is connected to the.

In the lamp annealing apparatus having the configuration shown in FIG. 5, the processing gas heated by the low-temperature side induction heating gas heater 28a is supplied to one gas supply pipe 80a inserted into the heat treatment furnace 78, and the other gas supply pipe 80a is supplied to the other gas supply pipe 80a. Gas supply pipe 80
The processing gas b is supplied with a processing gas which is heated by the high-temperature side induction heating gas heater 28b and has a higher temperature than the temperature of the processing gas supplied to the one gas supply pipe 80a. The processing gas at a relatively low temperature flows out from the gas outlet 82a of the one gas supply pipe 80a toward the center of the substrate W, and the substrate W flows out of the gas outlet 82b of the other gas supply pipe 80b. High-temperature processing gas flows out toward the periphery of the. For this reason, although the temperature of the substrate W accommodated in the heat treatment furnace 78 and heated by the lamp heater 24 is generally higher than the temperature of the peripheral portion, the substrate W is directed toward the central portion of the substrate W. By making the temperature of the processing gas flowing out of the substrate W lower than the temperature of the processing gas flowing out toward the peripheral portion of the substrate W, the temperature of the central portion of the substrate W and the temperature of the peripheral portion of the substrate W become equal. As a result, the temperature uniformity in the plane of the substrate W is further improved. In addition, since the temperature distribution is reversed during the temperature rise, the control temperatures of the respective heaters may be reversed.

In the lamp annealing apparatus shown in FIG. 6, a gas supply passage 92 communicating with a gas supply port of the heat treatment furnace 10 is provided with an induction heating gas heater 94 interposed therebetween. Are branched into a processing gas supply path 96 and a purge gas supply path 98 on the gas introduction side of the induction heating gas heater 94. The branched gas supply paths 96 and 98 are provided with electromagnetic on-off valves 100 and 102 and mass flow controllers 104 and 106, respectively. The processing gas supply path 96 is provided with a processing gas, for example, an oxygen gas supply unit. (Not shown), and the purge gas supply passage 98 is connected to a gas supply unit (not shown) for purge gas, for example, nitrogen. In the lamp annealing apparatus having such a configuration, the two electromagnetic on-off valves 10
The processing gas supplied into the heat treatment furnace 10 is switched to the induction heating gas heater 9
4, the purge gas introduced into the heat treatment furnace 10 before and after the introduction of the processing gas can be heated as needed.

In the above embodiment, the case where the present invention is applied to a lamp annealing apparatus has been described. The present invention can also be applied to a heat treatment apparatus of a type (a film forming apparatus), a horizontal or vertical heat treatment furnace (a film forming apparatus), and the like.

[0032]

When the substrate heat treatment apparatus according to the first aspect of the present invention is used, contact of the processing gas with the substrate being heated increases the generation of defects in the substrate, and the processing gas is applied to the substrate after the temperature rise. Can prevent the temperature distribution in the substrate surface from deteriorating due to the touch, making it impossible to perform a uniform heat treatment. Therefore, it is possible to improve the product yield and the product quality. be able to.

In the substrate heat treatment apparatus according to the second aspect of the present invention, even if the coil generates heat due to the high-frequency current flowing through the coil of the induction heating gas heater, the temperature rise of the coil can be suppressed, so that it is safe.

In the substrate heat treatment apparatus according to the third aspect of the present invention, the temperature uniformity in the plane of the substrate can be further improved, so that the quality of the product can be improved.

[Brief description of the drawings]

FIG. 1 is a schematic diagram illustrating an example of an embodiment of the present invention and schematically illustrating a configuration of a lamp annealing apparatus.

FIG. 2 is a vertical sectional view of a main part showing an example of a configuration of an induction heating gas heater which is one of the components of the lamp annealing apparatus shown in FIG.

FIG. 3 is a main part longitudinal sectional view showing another example of the configuration of the induction heating gas heater.

FIG. 4 is a schematic diagram showing one example of a control system in the lamp annealing apparatus according to the present invention.

FIG. 5 is a schematic view of a lamp annealing apparatus showing another embodiment of the present invention.

FIG. 6 is a flow path configuration diagram of a lamp annealing apparatus showing still another embodiment of the present invention.

FIG. 7 is a schematic view showing an example of a schematic configuration of a conventional lamp annealing apparatus.

FIG. 8 is a schematic diagram showing another example of a schematic configuration of a conventional lamp annealing apparatus.

[Explanation of symbols]

W substrate 10, 78 Heat treatment furnace 12 Gas supply port of heat treatment furnace 14, 84 Gas exhaust port of heat treatment furnace 16, 86a, 86b, 92 Gas supply path 22 Susceptor 24 Lamp heater 28, 46, 28a, 28b, 94 Induction heating gas heater 30, 48 container 32, 50 coil 34 power supply device 36, 52 heating element 38, 54 container gas inlet 40, 56 container gas outlet 42 water cooling jacket 44 water cooling jacket channel 58 water channel 60, 76 temperature sensor 62 temperature controller 64 pyrometer 66 lamp heater power supply 68, 70 thyristor 72, 74 temperature controller 80a, 80b gas supply pipe 82a, 82b gas outlet of gas supply pipe 96 processing gas supply path 98 purge gas supply path

Claims (3)

[Claims] 1. A substrate heat treatment apparatus for supplying a processing gas into a heat treatment furnace through a gas supply path, heating a substrate housed in the heat treatment furnace by a heating means, and heat treating the substrate, wherein the gas supply path is interposed. An induction heating gas heater, wherein the induction heating gas heater is formed of a non-magnetic material at least in part, and has a closed structure having a gas inlet and a gas outlet, and a non-magnetic material on an outer surface of the container. And a heating element provided at a position corresponding to the coil-wound portion inside the container and formed of a conductive material. Substrate heat treatment apparatus. 2. The substrate heat treatment apparatus according to claim 1, further comprising cooling means for cooling a coil of the induction heating gas heater. 3. A first gas supply pipe arranged such that a gas outlet in a heat treatment furnace faces a central portion of a substrate accommodated in the heat treatment furnace, and a gas outlet in the heat treatment furnace has the gas outlet. A second gas supply pipe disposed so as to face a peripheral portion of the substrate housed in the heat treatment furnace, wherein each of the first gas supply pipe and the second gas supply pipe has the induction heating gas heater. 3. The substrate heat treatment apparatus according to claim 1, wherein a gas supply path interposed is connected, and processing gases at different temperatures are supplied to a central portion and a peripheral portion of the substrate housed in the heat treatment furnace.