JPH0590165A - Vapor growth apparatus - Google Patents

Abstract

(57) [Abstract] [Purpose] When forming a thin film on a substrate by vapor deposition,
An object of the present invention is to provide a vapor phase growth apparatus capable of improving the heating efficiency of the heating means and uniformizing the in-plane temperature distribution of the substrate to form a high quality thin film. [Structure] The substrate 2 is placed on a through hole 3a formed in the substrate holder 3 and having a diameter slightly smaller than the diameter of the substrate 2, and the temperatures of the substrate 2 and the substrate holder 3 are measured by thermometers 9a and 9b. By controlling the heater currents flowing from the heater power supplies 7a and 7b to the heaters 4a and 4b by the temperature control devices 8a and 8b, respectively, the substrate 2 and the substrate holder 3 are heated by the heaters 4a and 4b.
The heating temperature is independently controlled by b, so that the heating efficiency can be improved and the in-plane temperature distribution of the substrate 2 can be made uniform.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vapor phase growth apparatus used for manufacturing semiconductors and the like.

[0002]

2. Description of the Related Art A vapor phase growth apparatus for producing a semiconductor or the like by vapor-depositing a thin film of a semiconductor or the like on a substrate is constructed, for example, as shown in FIG.

As shown in this figure, in the conventional vapor phase growth apparatus, a substrate holder 102 on which a substrate 101 is placed, and a substrate holder 102 are detachably supported in a reaction furnace 100, and a rotary drive device 103 is provided at one end side. Rotating shaft 104 connected to
And a heater 105 for heating the substrate holder 102 and the substrate 101.

Further, a gas supply device 107 for supplying gas (raw material gas, carrier gas, etc.) into the reaction furnace 100 through a gas supply pipe 106 is arranged in the upper part of the reaction furnace 100, and exhaust gas is arranged in the lower part. Exhaust device 109 for adjusting pressure in the reaction furnace 100 and exhausting unreacted gas and the like via a pipe 108
Are arranged.

The conventional vapor phase growth apparatus is configured as described above, and the substrate 101 and the substrate holder 102 are heated to a predetermined temperature by the heating of the heater 105, and the rotation driving device 103 is driven to rotate at a predetermined rotation speed. And feed it into the reaction furnace 100 from the gas supply device 107 through the gas supply pipe 106 (for example, Si H ₂ C
l ₂ ) is supplied together with a carrier gas (for example, H ₂ ) to vapor-deposit a thin film such as a semiconductor on the substrate 101.

By the way, in the above-described conventional vapor phase growth apparatus, as shown in FIG. 8, a counterbore portion 102a is provided in a portion of the substrate holder 102 on which the substrate 101 is mounted, so that the in-plane temperature distribution of the substrate 101 to be heated is reduced. I try to make it uniform.

However, the substrate holder 10 as described above
When the substrate 101 is placed on the substrate 2, the peripheral edge portion of the substrate 101 which is in contact with the substrate holder 102 is the other portion (the counterbore portion 10).
The temperature becomes higher than that in 2a), and slips and the like may occur. Particularly in recent years, there is a strong demand for effective use of the entire surface of the substrate 101, and as described above, it is not efficient to sacrifice the peripheral edge of the substrate 101, and the temperature difference at the peripheral edge imparts to other portions. There is a demand for thin film uniformity that cannot be ignored.

Further, in the conventional vapor phase growth apparatus shown in FIG. 7, the substrate 1 is heated by heating the substrate holder 102 with the heater 105.
Since 01 is heated, a large amount of heat escapes from the front surface of the substrate 101 due to radiation or the like.

Therefore, when the substrate 101 warps due to a temperature difference between the front surface and the back surface, the contact state between the substrate 101 and the substrate holder 102 changes, and the heat transfer state from the substrate holder 102 to the substrate changes. Then, the in-plane temperature distribution of the substrate 101 becomes non-uniform, and slips or the like may occur.

Slip is a phenomenon in which in-plane temperature distribution of the substrate 101 occurs at a high temperature and a stress exceeding the yield stress of the substrate is generated to cause slip deformation along the crystal lattice. The stress is reduced, and slip is likely to occur due to thermal stress or the like due to the temperature distribution of the substrate 101.

[0011]

As described above, in the conventional vapor phase growth apparatus, since the in-plane temperature distribution of the substrate 101 placed on the substrate holder 102 becomes non-uniform, a high quality thin film is obtained. It was difficult to get.

The present invention has been made for the purpose of solving the above problems, and an object of the present invention is to provide a vapor phase growth apparatus capable of making the in-plane temperature distribution of a substrate uniform.

[0013]

In order to solve the above-mentioned problems, a first invention according to claim 1 is to arrange a raw material gas in a reaction furnace and to arrange it in the reaction furnace heated by a heating means. In a vapor phase growth apparatus for vapor-depositing a thin film on a substrate on a substrate holder, while supporting the substrate at the peripheral portion of the through hole by forming a through hole smaller than the diameter of the substrate in the substrate holder, The heating means is disposed on the opposite side of the substrate holder from the substrate, and the heating means heats the substrate and the holder by controlling the temperature substantially independently of each other.

In a second aspect of the present invention, a source gas is supplied into the reaction furnace and a thin film is formed on a substrate on a substrate holder arranged in the reaction furnace which is heated by the first heating means. In a vapor-phase growth apparatus for performing vapor-phase growth, a second heating means disposed on the opposite side of the substrate from the first heating means, the first heating means and the second heating means are substantially independent of each other. And a temperature control means for controlling the temperature.

In the second aspect of the invention, a soaking plate having a diameter substantially the same as that of the substrate is arranged below the substrate between the substrate and the heater, or is arranged so as to be in contact with the surface of the heating means. May be installed.

[0016]

In order to realize the uniformity of the in-plane temperature distribution of the substrate, it is necessary to change the heat transfer state from the substrate holder to the substrate due to the contact state between the substrate and the substrate holder being warped. In order to avoid it, it is necessary to contact only a part of the substrate with the substrate holder. Further, since the substrate holder shields the radiant heat from the heating means at the portion where the substrate holder contacts the substrate, the temperature of the substrate holder needs to be higher than that of the substrate in order to make the temperature of the substrate uniform. is there.

Further, when the heat escape from the surface of the substrate becomes large, the temperature difference between the front and back of the substrate becomes large and the warp becomes large, so that the contact state between the substrate holder and the substrate easily changes, and the substrate holder to the substrate is easily changed. The heat transfer state of the substrate changes in the plane of the substrate, and the in-plane temperature distribution of the substrate tends to become non-uniform. Therefore, if the heat escape from the substrate surface is reduced, the warp of the substrate is reduced, and even if the substrate warps and the contact state with the substrate holder changes, the change in heat transfer amount can be reduced. Therefore, it becomes possible to reduce the temperature change of the substrate.

Next, the specific operation of the present invention will be described.

According to the first aspect of the present invention, the substrate is supported by the peripheral portion of the substrate holder in which the through hole is formed, and the temperature of the substrate and the substrate holder is controlled separately to control the temperature of the substrate holder. By heating to a higher temperature,
It is possible to prevent the temperature change due to the warp of the substrate and also prevent the temperature change at the peripheral portion of the substrate, thereby making the in-plane temperature distribution of the substrate uniform.

According to the second aspect of the present invention, the temperature of the second heating means is controlled to control the heat radiation from the surface of the substrate to make the in-plane temperature distribution of the substrate uniform. be able to.

[0021]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail below based on the illustrated embodiments.

<First Embodiment> FIG. 1 is a schematic view showing a vapor phase growth apparatus according to the first embodiment. As shown in this figure, in the reaction furnace 1, a substrate holder 3 on which a substrate 2 is placed,
A heater 4 is provided.

A through hole 3a having a diameter slightly smaller than that of the substrate 2 is formed in the substrate holder 3.
The substrate 2 is placed in the recess 3b formed on the periphery of a. A cylindrical rotary shaft 5 is detachably connected to the lower peripheral surface of the substrate holder 3, and the rotary shaft 5 is connected to a rotary drive device 6.

The heater 4 is concentrically arranged under the substrate holder 3 into two heaters 4a and 4b in the rotating shaft 5 corresponding to the positions of the substrate 2 and the substrate holder 3 in a concentric manner. Heater power supplies 7a, 4a and 4b,
7b is connected. Each of the heaters 4a and 4b has temperature controllers 8a and 8b for controlling the outputs of the heater power supplies 7a and 7b to control the temperatures of the heaters 4a and 4b, and a thermometer such as a radiation thermometer for measuring the temperature of the substrate 2. 9a and 9b are connected. The thermometers 9a and 9b are arranged outside the windows 1a and 1b formed on the upper side surface of the reaction furnace 1 and made of quartz or the like. The thermometers 9a and 9b may be provided in the reaction furnace 1. The means for measuring the temperature may be other well-known means such as a thermocouple.

A gas supply device 11 for supplying a gas such as a raw material gas and a carrier gas into the reaction furnace 1 via a gas introduction pipe 10 is connected to the upper part of the reaction furnace 1, and the lower part of the reaction furnace 1 is connected to the gas supply device 11. A gas exhaust pipe 12 is connected to an exhaust device 13 for adjusting the pressure in the reaction furnace 1 and exhausting unreacted gas and the like.

The vapor phase growth apparatus according to the present embodiment is constructed as described above, the exhaust apparatus 13 exhausts the inside of the reaction furnace 1 to adjust the pressure inside the reaction furnace, and the heaters 4a and 4b heat the substrate. 2 and the substrate holder 3 are heated to a predetermined temperature, and the substrate holder 3 is rotated by the rotation driving device 6.
Then, the substrate 2 is rotated, and the gas supply device 11 supplies the carrier gas (eg, H ₂ ) together with the source gas (eg, SiH ₂ ).
_By supplying ₂ Cl ₂ ) into the reaction furnace 1, a semiconductor thin film is vapor-phase grown on the substrate 2.

As described above, in this embodiment, the substrate 2 is directly heated by the inner heater 4a through the through hole 3a, and the holder 3 is directly heated by the outer heater 4b, so that the heating efficiency is improved, so that the heaters 4a and 4b are heated. The heating temperature can be kept low.

Further, the temperatures of the substrate 2 and the substrate holder 3 are measured by the thermometers 9a and 9b, and the heater currents flowing from the heater power supplies 7a and 7b to the heaters 4a and 4b are controlled by the temperature control devices 8a and 8b, respectively. Thus, the heating temperatures of the substrate 2 and the substrate holder 3 are separately controlled by the heaters 4a and 4b, so that the temperature control of the substrate holder 3 required to uniformly heat the substrate 2 is prevented from interfering with the substrate temperature. It can be done small. At this time, the heating temperature of the substrate holder 3 is at least 10 ° C. higher than the heating temperature of the substrate 2.
By controlling the temperature to be higher than a certain level, the peripheral portion of the substrate 2 is supported by the substrate holder 3, so that the temperature drop due to the shielding of the radiant heat from the heater 4b is compensated, and the in-plane surface of the substrate 2 is compensated. The uniformity of temperature distribution can be further improved.

Further, in the above-mentioned embodiment, the heater 4 is divided into two as heating means. However, the substrate 4 and the substrate holder 3 are separately heated without dividing the heater 4 or into two or more. You may control. Further, as the heating means, heating with a high-frequency coil or a lamp may be used instead of the heater.

Further, in the above-mentioned embodiment, the substrate 2 is supported by the entire surface of the concave portion 3b formed in the peripheral edge of the through hole 3a of the substrate holder 3, but a plurality of protruding portions are formed in the concave portion 3b and the protruding portions are formed. The substrate 2 may be supported. Further, not only the peripheral portion but also the central portion of the substrate 2 and other portions may be supported.

<Second Embodiment> FIG. 2 is a schematic view showing the main part of a vapor phase growth apparatus according to the second embodiment. In this embodiment, a soaking plate 14 made of a member having a good thermal conductivity, such as carbon, having a diameter substantially the same as the diameter of the substrate 2 is provided between the substrate 2 and the heater 4a.
The heat equalizing plate 14 is supported by the rotating shaft 5 by the support rod 15. The soaking plate 14 may be fixed to another portion or another method. Other configurations are similar to those of the first embodiment shown in FIG.

As described above, in this embodiment, the heater 4a is provided by disposing the soaking plate 14 between the substrate 2 and the heater 4a.
The uniform heating plate 14 can uniformly heat the entire surface of the uniform heating plate 14, and the uniform heating plate 14 can uniformly heat the entire surface of the substrate 2. Therefore, even if the temperature of the heater 4a that heats the substrate 2 is somewhat uneven, by heating the substrate 2 after uniformizing the temperature distribution by the soaking plate 14, the in-plane temperature distribution of the substrate 2 becomes uniform. Can be planned.

Further, since the substrate holder 3 is not required to have uniform heat distribution as much as the substrate 2, the above-mentioned uniform plate may or may not be provided between the heater 4b and the substrate holder 3. When providing a soaking plate, the diameter of the soaking plate may be made larger than that of the substrate 2, and the soaking plate may be provided between the heater 4 b and the substrate holder 3.

<Third Embodiment> FIG. 3 is a schematic view showing a main part of a vapor phase growth apparatus according to the third embodiment. In this embodiment, the heater 4 is located below the substrate 2 and the substrate holder 3.
The soaking plate 14 is arranged so as to be almost in contact with the surfaces of a and 4b, and the soaking plate 14 is mounted on the heater. Other configurations are similar to those of the first embodiment shown in FIG.
The soaking plate 14 may be divided into two or more parts at positions having substantially the same diameter as the substrate 2.

As described above, in this embodiment, the heaters 4a, 4
By arranging the soaking plate 14 so as to be in contact with the surface of b, even if the heaters 4a and 4b have uneven temperatures, the soaking plate 14 that is uniformly heated can indirectly serve for the substrate 2,
By heating the substrate sensor 3, the in-plane temperature distribution of the substrate 2 can be made uniform. Moreover, the soaking plate 14
And the heaters 4a and 4b are in contact with each other, the temperatures of the soaking plate 14 and the heaters 4a and 4b become substantially equal,
It is possible to lower the temperatures of a and 4b, extend the life of the heaters 4a and 4b, and reduce the emission of impurities from the members. In addition, the structure of the soaking section becomes simple.

<Fourth Embodiment> FIG. 4 is a schematic view showing a main part of a vapor phase growth apparatus according to the fourth embodiment. In this embodiment, the heater 4 is located below the substrate 2 and the substrate holder 3.
The heat equalizing plate 14 is arranged below the a and 4 b, and the heat equalizing plate 14 is supported by the inner peripheral surface of the rotating shaft 5. Other configurations are similar to those of the first embodiment shown in FIG.

As described above, in this embodiment, the heaters 4a, 4
By disposing the soaking plate 14 on the lower side of b, the heater 4
It is possible to reduce the non-uniformity of the temperatures of a and 4b. Further, since the heat of the heaters 4a and 4b directly heats the substrate 2, the heating efficiency is improved, and the temperature of the heaters 4a and 4b can be suppressed to be low.

<Fifth Embodiment> FIG. 5 is a schematic view showing a vapor phase growth apparatus according to a fifth embodiment. As shown in this figure, a substrate holder 3 on which a substrate 2 is placed, a first heater 16, and a heat equalizing plate 14 are arranged in a lower portion of a reaction furnace 1.
A disc-shaped straightening plate 17 having a plurality of holes 17a is disposed in the upper portion of the reaction furnace 1.

The heat equalizing plate 14 is arranged below the substrate holder 3 via a plurality of support rods 15, and the cylindrical rotating shaft 5 is connected to the lower peripheral surface of the heat equalizing plate 14. .. Rotating shaft 5
Are connected to the rotary drive device 6.

The substrate holder 3 is formed with a through hole 3a having a diameter slightly smaller than the diameter of the substrate 2.
The substrate 2 is placed in the recess 3b formed on the periphery of a.

The first heater 16 is arranged in the rotary shaft 5 below the heat equalizing plate 14, and the first heater 16 controls the heater power source 7 and the output of the heater power source 7 to control the first heater 16. A temperature control device 8 for controlling the temperature of the heater 16 and a thermometer 18 such as a radiation thermometer for measuring the temperature of the substrate 2 are connected. The thermometer 18 is disposed outside the window 1a formed on the upper side surface of the reaction furnace 1 and made of quartz or the like. The thermometer 18 may be provided in the reaction furnace 1.

A gas supply device 11 for supplying a gas such as a raw material gas and a carrier gas into the reaction furnace 1 via a gas introduction pipe 10 is connected to an upper side surface of the reaction furnace 1 located on the straightening plate 17. At the bottom of the reactor 1, there is a gas discharge pipe 12
The exhaust device 13 for adjusting the pressure in the reaction furnace 1 and exhausting unreacted gas and the like is connected via the.

A window 19 made of a material such as quartz that transmits heat rays is formed in the upper portion of the reaction furnace 1.
Above the plate 9 is a heating plate 20 and a second heating plate 20 for heating the heating plate 20.
The heater 21 is provided.

The second heater 21 has a heater power source 22 and
A temperature control device 23 that controls the output of the heater power supply 22 to control the temperature of the second heater 21 and a thermometer 24 such as a radiation thermometer that measures the temperature of the heating plate 20 are connected.

The vapor phase growth apparatus according to the present embodiment is constructed as described above, and the exhaust device 13 exhausts the inside of the reaction furnace 1 to adjust the pressure inside the reaction furnace, and the first heater 16 heats it. The substrate 2 and the substrate holder 3 are heated to a predetermined temperature from the lower side (back side), and the hot plate 20 is heated by the second heater 21 to control the heat radiation amount from the substrate 2 and the substrate holder 3 by the hot plate 20. Then, the rotary drive device 6
The substrate holder 3 and the substrate 2 are rotated at a predetermined rotational speed by the rotational driving of the gas, and the source gas (for example, SiH ₂ Cl) together with the carrier gas (for example, H ₂ ) is supplied by the gas supply device 11.
_By supplying ₂ ) into the reaction furnace 1, a semiconductor thin film is vapor-phase grown on the substrate 2.

At this time, the temperature of the substrate 2 is measured by the thermometer 18 so that the substrate 2 is controlled to a predetermined temperature (for example, 1000 ° C.) by the temperature controller 8 from the heater power source 7 to the first heater 16. Controls the heater current flowing through. Also,
The temperature controller 23 controls the temperature of the heating plate 20 heated by the second heater 21 to a predetermined temperature (for example, 1000 ° C. which is the same as the temperature of the substrate 2) from the heater power supply 22 to the second heater 21. Controls the heater current flowing through.

FIG. 6 is an experimental result showing the relationship between the temperature of the heating plate 20 and the in-plane temperature distribution of the substrate 2. The peripheral portion of the substrate 2 when the temperature of the central portion of the substrate 2 is controlled to 1000 ° C. The temperature is plotted against the hot plate temperature.

As is clear from the results of this experiment, the substrate 2
When the temperature of the hot plate 20 is set to a range of 900 to 1200 ° C. (that is, the temperature of the hot plate 20 is −100 to 200 ° C. with respect to the temperature of the substrate 2).
In this case, the uniformity of the in-plane temperature distribution of the substrate 2 is improved.

As described above, in addition to heating the substrate 2 from the lower side by the first heater 16, the substrate 2 is also heated by the hot plate 20 heated by the second heater 21 from above so that the substrate 2 is heated. Since heat radiation due to radiation from the surface of 2 can be greatly reduced, it is possible to improve the substrate heating efficiency and make the temperature distribution within the substrate uniform.

Further, in the above embodiment, the second heater 21
Although the heating plate 20 is provided outside the reaction furnace 1, it may be provided above the substrate 2 in the reaction furnace 1, and the heating plate 20 may or may not be used.

Further, in the above embodiment, the heater is used as the second heating means, but other than this, for example, heating by a high frequency coil or the like may be used.

[0052]

As described above in detail with reference to the embodiments, according to the present invention, the in-plane temperature distribution of the substrate can be made uniform, so that the substrate may be slipped. It is possible to obtain a high quality thin film which is prevented.

Further, since the heating efficiency can be improved to lower the temperature of the heating means, generation of impurities in the reaction furnace can be suppressed, and a high quality thin film can be grown.

[Brief description of drawings]

FIG. 1 is a schematic view showing a vapor phase growth apparatus according to a first embodiment of the present invention.

FIG. 2 is a schematic view showing a main part of a vapor phase growth apparatus according to a second embodiment of the present invention.

FIG. 3 is a schematic view showing a main part of a vapor phase growth apparatus according to a third embodiment of the present invention.

FIG. 4 is a schematic view showing a main part of a vapor phase growth apparatus according to a fourth embodiment of the present invention.

FIG. 5 is a schematic view showing a vapor phase growth apparatus according to a fifth embodiment of the present invention.

FIG. 6 is a diagram showing a relationship between a hot plate temperature and a temperature distribution in a substrate surface.

FIG. 7 is a schematic view showing a conventional vapor phase growth apparatus.

FIG. 8 is a schematic view showing a substrate holder of a conventional vapor phase growth apparatus.

[Explanation of symbols]

 1 Reactor 2 Substrate 3 Substrate Holder 3a Through Hole 4, 4a, 4b Heater 8, 8a, 8b, 23 Temperature Control Device 9a, 9b, 18, 24 Thermometer 10 Gas Supply Device 14 Soaking Plate 15 Rectifier Plate 16 1st Heater 20 hot plate 21 second heater

Claims (4)

[Claims] 1. A vapor phase growth apparatus for supplying a source gas into a reaction furnace and performing vapor phase growth of a thin film on a substrate on a substrate holder arranged in the reaction furnace which is heated by a heating means,
A through hole having a diameter smaller than that of the substrate is formed in the substrate holder to support the substrate at the peripheral portion of the through hole, and the heating means is arranged on the side opposite to the substrate of the substrate holder. In the vapor phase growth apparatus, the substrate and the holder are heated independently of each other under temperature control. 2. A vapor phase growth apparatus for supplying a raw material gas into a reaction furnace and performing vapor phase growth of a thin film on a substrate on a substrate holder arranged in the reaction furnace which is heated by a first heating means. A second heating means arranged on the opposite side of the substrate from the first heating means; and a temperature control means for controlling the temperature of the first heating means and the second heating means substantially independently of each other. A vapor phase growth apparatus characterized by: 3. A heat equalizing plate having a diameter substantially the same as that of the substrate is arranged between the substrate and the heating means.
Alternatively, the vapor phase growth apparatus according to claim 2. 4. The vapor phase growth apparatus according to claim 1, wherein a soaking plate is provided so as to be substantially in contact with the heating means.