JP3536057B2 - Material layer forming device - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a material layer forming apparatus, and more particularly, to various materials such as thin films and thick films of semiconductors and metals on a substrate made of various materials. The present invention relates to a material layer forming apparatus suitable for use in forming a layer.

[0002]

2. Description of the Related Art As a conventional material layer forming apparatus, for example,
A crystal growth apparatus is known in which a semiconductor crystal thin film is formed as a material layer on a semiconductor wafer as a substrate by using a vapor phase growth method.

FIG. 1 is a conceptual configuration explanatory view of a crystal growth apparatus as the above-mentioned conventional material layer forming apparatus. This crystal growth apparatus 100 has a crystal growth reaction furnace 104 whose periphery is covered with an RF heating coil 102. A susceptor 108 for supporting the semiconductor wafer 106 as a substrate and heating the semiconductor wafer 106 is provided therein.

An RF power supply 110 is connected to the RF heating coil 102, and an RF control device 112 composed of a microcomputer is connected to the RF power supply 110.

Then, by the RF control device 112, R
The output of the F power supply 110 is controlled. That is, the RF controller 112 controls the RF power supply 110 to drive the RF heating coil 1
02, the RF heating coil 102 heats the susceptor 108 in response to the power supplied from the RF power supply 110.

That is, in the crystal growth apparatus 100, the susceptor 108 is heated by the eddy current induced heating by feeding power from the RF power supply 110 to the RF heating coil 102.

FIG. 2 shows a conventional susceptor 108.
Although a perspective view of the conceptual configuration of the susceptor 108 is shown.
Has a substantially rectangular parallelepiped shape, and its upper surface 108a has
A holding portion 108b having a concave shape for arranging the semiconductor wafer 106 is formed.

A thermocouple (not shown) for monitoring the temperature of the susceptor 108 is embedded in the susceptor 108.

The susceptor 108 is made of carbon, for example.

On the other hand, in the crystal growth reaction furnace 104, gas introduction holes 104a for introducing various gases such as a raw material gas and a carrier gas which are raw materials of a semiconductor crystal thin film formed on the semiconductor wafer 106, and crystal growth. Gas exhaust hole 1 for exhausting various gases introduced into the reaction furnace 104
04b are formed.

In the above structure, in order to form a desired semiconductor crystal thin film on the semiconductor wafer 106 arranged in the holding portion 108b of the susceptor 108, the raw materials necessary for forming the desired semiconductor crystal thin film are used. The raw material gas is supplied from the gas introduction hole 104a to the crystal growth reactor 104.
Supply inside.

At this time, based on a monitor of a thermocouple (not shown) embedded in the susceptor 108, the susceptor is driven by the RF heating coil 102 in response to power supplied from the RF power source 110 controlled by the RF controller 112. 1
08 is heated, and due to the heat conduction from the heated susceptor 108, the semiconductor wafer 106 also has an optimum temperature for forming a semiconductor crystal thin film by crystal growth (hereinafter, “the semiconductor crystal thin film is formed by crystal growth. The "optimal temperature" is appropriately referred to as "optimal growth temperature").

For this reason, the source gas introduced into the crystal growth reaction furnace 104 is decomposed and reacted by heat, and a semiconductor crystal thin film is formed on the semiconductor wafer 106 by crystal growth.

Here, in the crystal growth apparatus 100,
In order to keep the temperature of the semiconductor wafer 106 stable at the optimum growth temperature during crystal growth, the susceptor 108 is used.
Is formed to have a relatively large heat capacity, thereby suppressing fluctuations in the temperature of the susceptor 108 and stabilizing the temperature of the semiconductor wafer 106 heated by heat conduction from the susceptor 108. There is.

By the way, when a semiconductor crystal thin film is formed on a semiconductor wafer 106 using the crystal growth apparatus 100, a plurality of semiconductor crystal thin films having different optimum growth temperatures may be alternately formed.

In this case, in accordance with the monitor of the thermocouple (not shown) embedded in the susceptor 108, the RF
The temperature of the susceptor 108 needs to be appropriately changed by controlling the output of the RF power supply 110 by the control device 112 and controlling the power supply from the RF power supply 110 to the RF heating coil 102. Since it is large, it is difficult to rapidly change the temperature, and thus it is also difficult to rapidly change the temperature of the semiconductor wafer 106 to a different optimum growth temperature (see FIG. 5).

That is, when the temperature of the susceptor 108 is raised or lowered, the change is gentle and it takes a considerable time.

Therefore, when alternately forming a plurality of semiconductor crystal thin films having different optimum growth temperatures in the crystal growth apparatus 100, it takes time to switch the temperature of the semiconductor wafer 106, so that the entire processing time is long. There was a problem that

Further, if it takes time to switch the temperature of the semiconductor wafer 106, the quality of the semiconductor crystal thin film formed on the semiconductor wafer 106 may be deteriorated.

[0020]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned various problems of the prior art, and its object is to make the temperature of the substrate steep in a short time. An object of the present invention is to provide a material layer forming apparatus that can be changed to

[0021]

In order to achieve the above object, the invention according to claim 1 of the present invention is such that the temperature of a substrate placed on the susceptor is raised or lowered by raising or lowering the temperature of the susceptor. In the material layer forming apparatus for forming the material layer on the substrate while appropriately changing, the first block having the first heat capacity smaller than the predetermined heat capacity for arranging the substrate and the predetermined block not disposing the substrate. A second block having a second heat capacity larger than the heat capacity, wherein the first block and the second block are arranged with a predetermined gap therebetween and are separated from each other by the first block. The block and the second block are gently thermally coupled by heat radiation, an RF heating coil that heats the susceptor and can raise and lower the temperature in a pulsed manner, and Each detection means for individually detecting the temperature of the susceptor of the first block and the second block, based on a detection result of said detecting means, said R
Control for controlling power supply to the RF heating coil so that the F heating coil continuously heats, and controlling power supply to the RF heating coil so that the magnitude of the heating power of the RF heating coil changes in a pulse shape. The power supply to the RF heating coil is controlled by the control means based on the detection result of the detection means, and when the RF heating coil is continuously heated and is in a steady heating state, the susceptor of The first block is heated by heat radiation from the second block, the temperature of the entire system is controlled through loose thermal coupling due to heat radiation, and the heating power of the RF heating coil is pulsed. When the output of the RF heating coil is sharply increased in a short time, only the first block of the susceptor precedes the second block in a short time. When the temperature of the RF heating coil is rapidly decreased by being heated and the output of the RF heating coil is rapidly decreased in a short time, only the first block of the susceptor is preceded by the second block. Arranged in the first block and the first block of the susceptor in accordance with the switching timing at which the temperature of the RF heating coil is rapidly decreased and the heating power of the RF heating coil is changed in magnitude in a pulse shape. The height of the temperature of the above-mentioned substrate is changed in a pulse shape in a short time.

In the invention according to claim 2 of the present invention, the temperature of the susceptor is raised or lowered to appropriately change the temperature of the substrate placed on the susceptor, and the substance is placed on the substrate. In a material layer forming apparatus for forming a layer, a first block having a first heat capacity smaller than a predetermined heat capacity for arranging a substrate and a second block having a second heat capacity larger than the predetermined heat capacity for not disposing a substrate. A block, the first block and the second block are arranged with a predetermined gap, and the first block and the second block emit heat. A susceptor that is loosely thermally coupled by
When the RF heating coil that heats the susceptor and raises and lowers the temperature in a pulsed manner is provided, and the RF heating coil is continuously heated and is in a steady heating state, from the second block of the susceptor, The first block is heated by the heat radiation of, and the temperature of the entire system is controlled through the loose thermal coupling by the heat radiation, and the magnitude of the heating power of the RF heating coil changes in a pulse shape. When the output of the RF heating coil is sharply increased in a short time, only the first block of the susceptor is heated earlier than the second block in a short time to rapidly increase the temperature. ,
When the output of the RF heating coil is sharply lowered in a short time, only the first block of the susceptor is preliminarily cooled by the second block in a short time and then rapidly cooled. The high temperature of the first block of the susceptor and the temperature of the substrate arranged in the first block are pulsed in accordance with the switching timing for changing the magnitude of the heating power of the RF heating coil in a pulse manner. It is designed to be changed into high and low in a short time.

Further, according to a third aspect of the present invention, the material on the substrate is appropriately changed by raising or lowering the temperature of the susceptor to appropriately change the temperature of the substrate placed on the susceptor. In a material layer forming apparatus for forming a layer, a first block having a first heat capacity smaller than a predetermined heat capacity for arranging a substrate and a second block having a second heat capacity larger than the predetermined heat capacity for not disposing a substrate. A block and a spacer having a predetermined thickness, the first block and the second block are connected to each other via the spacer, and the first block and the second block are connected to each other. The block has a susceptor that is gently thermally coupled by heat radiation, and an RF heating coil that heats the susceptor and can raise and lower the temperature in a pulse shape. If the heating coil is continuously heated steady heating state is the first block is heated by thermal radiation from the second block of the susceptor,
The temperature of the entire system is controlled through loose thermal coupling due to heat radiation, the magnitude of the heating power of the RF heating coil changes in a pulse manner, and the output of the RF heating coil is sharply increased in a short time. In this case, only the first block of the susceptor is heated earlier than the second block in a short time to steeply raise the temperature, while the output of the RF heating coil is steeply lowered in a short time. In such a case, only the first block of the susceptor is preliminarily cooled by the second block in a short time, and the temperature is sharply lowered.
The high temperature of the first block of the susceptor and the temperature of the substrate arranged in the first block follow the switching timing of changing the magnitude of the heating power of the heating coil in a pulse shape. It is designed to change to high and low in a short time.

[0024]

[0025]

Therefore, according to the invention of claim 1 of the present invention, the invention of claim 2 of the present invention, and the invention of claim 3 of the present invention, the first block has a heat capacity. Is small, the temperature is rapidly increased by heating in a short time, and the temperature is decreased in a short time. For this reason,
The temperature of the substrate arranged in the first block can be rapidly changed in a short time.

[0027]

Further, like the invention according to claim 4 of the present invention, in the invention according to any one of claim 1, claim 2 or claim 3 of the invention, the A light source for irradiating light to one block to heat it may be provided.

Here, the light source can be turned on or off in a pulsed manner as in the invention according to claim 5 of the present invention.

Further, like the invention described in claim 6 of the present invention, any one of claim 1, claim 2, claim 3, claim 4 or claim 5 of the invention is described. In the invention, the first block and the second block may be formed of carbon, and the volume of the first block may be smaller than the volume of the second block.

Further, like the invention described in claim 7 of the present invention, any one of claim 1, claim 2, claim 3, claim 4, claim 5 or claim 6 of the present invention. In the invention described in Item 1, the first block and the second block
The block may be formed of carbon, the first block may be formed in a thin plate shape, and the second block may be formed in a thick plate shape.

[0032]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, an example of an embodiment of a material layer forming apparatus according to the present invention will be described in detail with reference to the accompanying drawings.

In the embodiments described below, the apparatus for forming a material layer according to the present invention is used for crystal growth in which a semiconductor crystal thin film as a material layer is formed on a semiconductor wafer as a substrate by using a vapor phase epitaxy method. The case of implementation as an apparatus will be described.

Further, in the following description with reference to FIGS. 3 to 9, the same or corresponding configuration as that shown in FIGS. 1 and 2 will be described with reference to FIGS. By using the same reference numerals as those used, the detailed description of the configuration and operation will be omitted.

First, FIG. 3 shows a conceptual configuration explanatory view of a first embodiment of a material layer forming apparatus according to the present invention. In the first embodiment, as described above, the material layer forming apparatus according to the present invention is implemented as a crystal growth apparatus. However, the crystal growth apparatus shown in FIGS. 1 and 2 has a susceptor structure. Is different.

That is, as shown in FIG. 4, the susceptor 12 of the crystal growth apparatus 10 according to the first embodiment is as follows.
It is divided into a first block 12a and a second block 12b, and the first block 12a and the second block 12 are divided.
b is connected via a spacer 14 and has a substantially rectangular parallelepiped shape as a whole. The first block 1
The 2a, the second block 12b, and the spacer 14 are each made of carbon or the like.

The susceptor 12 will now be described in more detail. The first block 12a has a thin plate shape (for example, the thickness is 10 mm or less), and has a heat capacity higher than that of the second block 12b. Is set to be small.

The upper surface 12aa of the first block 12a
A concave-shaped holding portion 12ab for arranging the semiconductor wafer 106 is formed therein.

A thermocouple (not shown) for monitoring the temperature of the first block 12a is embedded in the first block 12a.

On the other hand, the second block 12b has a thick plate shape (for example, the thickness is 15 mm or more) having a large thickness, and is set to have a heat capacity larger than that of the first block 12a. .

The sizes of the first block 12a and the second block 12b are, for example, such that the volume of the first block 12a is about one third (1/3) or less of the volume of the second block 12b. It is preferable that the size is set to a small value. In this way, the volume of the first block 12a is adjusted to the second block 12a.
If the volume of b is about one-third (1/3) or less, the first
The heat capacity of the block 12a is about one third (1/3) or less of the heat capacity of the second block 12b.

Further, the spacer 14 has a predetermined thickness t.
(For example, the thickness is 10 mm or less).

Then, the first block 12a, the second block 12b, and the spacer 14 are connected so that the spacer 14 is sandwiched between the first block 12a and the second block 12b. The spacer 14
Are arranged on two opposite side edges of the first block 12a (second block 12b).

Therefore, in this susceptor 12,
The first block 12a and the second block 12b are arranged so as to be separated from each other so as to have a predetermined gap g (predetermined gap g = predetermined thickness t), and the first block 12a and the second block 12b. Is a material that is gently thermally coupled by heat radiation.

In the above structure, in order to form a desired semiconductor crystal thin film on the semiconductor wafer 106 arranged on the holding portion 12ab of the first block 12a of the susceptor 12, in order to form the desired semiconductor crystal thin film. A raw material gas, which is a raw material necessary for the above, is supplied into the crystal growth reaction furnace 104 through the gas introduction hole 104a.

At this time, the power is supplied from the RF power source 110 controlled by the RF controller 112 based on the monitor of the thermocouple (not shown) embedded in the first block 12a and the second block 12b. Accordingly, the RF heating coil 102 heats the first block 12 a and the second block 12 b of the susceptor 12.

Here, in the susceptor 12, RF
In the steady heating state by the continuous heating of the heating coil 102, the first block 12a is heated by the heat radiation from the second block 12b, and the temperature of the entire system is controlled through a weak thermal coupling called heat radiation. It has the same temperature stability as the conventional susceptor described in the section "Prior Art".

The first block 1 of the susceptor 12
Due to the heat conduction from 2a, the semiconductor wafer 106 is also heated to the optimum growth temperature.

For this reason, the source gas introduced into the crystal growth reaction furnace 104 is decomposed and reacted by heat, and a semiconductor crystal thin film is formed on the semiconductor wafer 106 by crystal growth.

Here, in order to alternately form a plurality of semiconductor crystal thin films having different optimum growth temperatures on the semiconductor wafer 106 using the crystal growth apparatus 10, the first block 12a and the second block 12b are formed. Based on a monitor of an embedded thermocouple (not shown), the RF controller 112 controls the output of the RF power source 110 to generate R
The first block 12a of the susceptor 12 is controlled by controlling the power supply from the F power source 110 to the RF heating coil 102.
Also, the temperature of the second block 12b is once kept relatively low.

Then, after that, the RF control device 11 is restarted.
2 controls the output of the RF power source 110 to
When the output of the RF heating coil 102 is steeply increased in a short time by controlling the power supply from the RF heating coil 102 to the RF heating coil 102, only the first block 12a having a small heat capacity is advanced in the susceptor 12. As a result, the second block 12b having a large heat capacity is heated in a short time and the temperature thereof is sharply raised, so that the second block 12b having a large heat capacity is slowly heated similarly to the conventional susceptor described in the section "Prior Art".

Therefore, only the first block 12a rapidly raises its temperature in a short time, whereby the temperature of the semiconductor wafer 106 can be rapidly changed to a different optimum growth temperature in a short time. (See Figure 5).

That is, when the temperature of the first block 12a rises, the change is abrupt in a short time, which is much shorter than that of the conventional susceptor described in the section "Prior Art". Can be heated.

On the other hand, after the temperature of the first block 12a is rapidly raised in a short time, the output of the RF power supply 110 is controlled by the RF controller 112 again while the temperature of the second block 12b does not rise so much. When the output of the RF heating coil 102 is sharply decreased in a short time by controlling the power supply from the RF power supply 110 to the RF heating coil 102, the temperature of the second block 12b does not rise so much and Since the heat radiation to the 1st block 12a is weak and the heat capacity of the 1st block 12a is small, only the 1st block 12a will be lowered in advance in a short time, and only the 1st block 12a will decrease its temperature. The semiconductor wafer 1 is cooled down rapidly in a short time.
The temperature of 06 can be rapidly changed to a different optimum growth temperature in a short time (see FIG. 5).

That is, when the temperature of the first block 12a is lowered, the change is steep in a short time. Compared with the conventional susceptor described in the section "Prior Art", the first block 12a can be changed in a significantly shorter time. The temperature can be lowered.

Accordingly, the RF control device 112 alternately switches the magnitude of the output of the RF power source 110 in a pulse shape to change the magnitude of the heating power of the RF heating coil 102 in a pulse shape. The first block 12 is made to follow the timing very much.
The temperature of the semiconductor wafer 106 and the temperature of the semiconductor wafer 106 can be changed in a pulsed manner in a short time.

When controlling the temperature of the first block 12a and the semiconductor wafer 106, thermocouples (not shown) are embedded in the first block 12a and the second block 12b, respectively, as described above. Therefore, by individually monitoring these thermocouples, the temperatures of the first block 12a and the second block 12b are individually detected, and the output of the RF power supply 110 is output by the RF controller 112 based on the detection result. Is controlled to perform appropriate temperature control.

Next, FIG. 6 is a conceptual structural explanatory view of the second embodiment of the material layer forming apparatus according to the present invention. The crystal growth apparatus 20 according to the second embodiment is
As a heating means for heating the first block 12a and the semiconductor wafer 106, in addition to the RF heating coil 102, a light source 22 as an external heating light source for irradiating light is provided.

The light source 22 includes a lighting / lighting-off control device 24.
The lighting and extinguishing thereof are controlled by the.

As the light source 24, for example, a laser or a lamp can be used.

Therefore, in this crystal growth apparatus 20, the first block 12a and the semiconductor wafer 106 are
When the light source 22 is turned on by the control of the lighting / extinguishing control device 24 when the temperature of the light source is rapidly raised in a short time, the heat energy accompanying the light irradiation of the light source 22 is synergized, and thus the first embodiment It is possible to raise the temperature of the first block 12a and the semiconductor wafer 106 in a shorter time than in the case of this form.

In the above-described first and second embodiments, the first block 12a has a small heat capacity, so that the temperature stability is deteriorated.
When an instantaneous temperature change is required when forming a thin film such as a quantum well, such temperature instability does not significantly affect the thin film formation.

Further, when forming a thin film in a normal steady state, the temperature of the first block 12a is controlled by thermal coupling with the second block 12b by heat radiation as described above, so that sufficient temperature stability is achieved. You can get sex.

Here, using each of the embodiments described above,
A process for actually growing a crystal of a semiconductor will be described.

First, the case of forming an InGaN / AlGaN quantum well structure will be described with reference to FIG.

That is, the InGaN layer used as an active layer of a green LED, a blue LED or the like is crystallized at a much lower temperature than the GaN layer and the AlGaN layer having a band energy larger than that of the InGaN layer in order to secure the In incorporation rate. Need to grow. That is, the optimum growth temperature of the InGaN layer is considerably lower than that of the GaN layer and the AlGaN layer.

Furthermore, the temperature rising process after crystal growth for the InGaN layer is not desirable because it induces mutual diffusion of atoms between the quantum well layer and the barrier layer.

Therefore, conventionally, In _x Ga _1-x N has been used.
The crystal growth was performed at the optimum temperature for the crystal growth of the layer, and the crystal growth was not performed at the optimum growth temperature for the GaN layer and the AlGaN layer as the carrier confinement layer.

Therefore, conventionally, as the carrier confinement layer, a carrier confinement layer having a low optimum growth temperature of In _y Ga _1-y N (y <x) is used, or the optimum temperature is removed and carrier confinement is performed by GaN or AlGaN. There was no choice but to take a method of crystal growing the layer.

However, when In _y Ga _1-y N (y <x) is used as the carrier confinement layer, the degree of change in composition is small, the confinement energy difference is small, and the temperature characteristic is deteriorated. When GaN or AlGaN is used for the layer, there arises a problem that the crystal quality is deteriorated and desired characteristics cannot be obtained.

However, when the temperature control of the substrate is instantaneously performed by using the above-described first embodiment or second embodiment, the residence time at high temperature is significantly shorter than the conventional method described above. Therefore, mutual diffusion of atoms between the quantum well layer and the barrier layer can be suppressed, and the desired growth temperature can be realized while maintaining the desired structure, and high quality can be expected.

Next, the case of forming the Mg doping layer will be described with reference to FIG.

That is, Cp is used for p-type doping with Mg.
_An organometallic gas called ₂ Mg is used. A relatively high-temperature growth condition is required to promote this decomposition, but generally in a light emitting element such as an LED or a laser, an InAlGaN-based quantum well structure is already present as a base. for that reason,
It is necessary to suppress interdiffusion of atoms in the quantum well structure, and the growth temperature of the Mg-doped layer cannot be raised sufficiently.

Conventionally, a device is formed by a post-growth post-annealing process such as a post-annealing process. However, the substrate temperature control can be performed by using the above-described first embodiment or second embodiment. If the annealing is performed instantaneously during crystal growth, the post-annealing process need not be performed, and the quality of the p-type layer can be improved.

Next, the applicant of the present invention filed Japanese Patent Application No. 11-3545.
GaN filed as No. 63 “Method for forming semiconductor layer”
9 shows a case of supplying TESi, which is a transition suppressing substance that suppresses threading transition of group III nitride semiconductors such as
Will be described with reference to.

That is, the applicant of the present invention has filed Japanese Patent Application No. 11-3545.
No. 63 “Method for forming semiconductor layer”,
In order to suppress threading dislocations in the group III nitride semiconductor, it is necessary to control the supply amount of TESi, which is a dislocation suppressing substance, very strictly.

By the way, when TESi is supplied at the same temperature as the growth temperature of the underlayer, Si is taken into the crystal surface through the decomposition of TESi due to the temperature.

However, if there is a subtle difference in the amount of Si taken in on the substrate as a surface distribution, the stability of the crystal quality will be hindered.

In order to prevent such a difference in the amount of Si taken in on the substrate as a surface distribution, the substrate temperature is once lowered to a low temperature (for example, 600 ° C. or lower) to adsorb TESi. . In this case, Si is adsorbed on the surface of the substrate with one ethyl group attached, and due to the ethyl group, Si does not adhere to more than two monolayers (self-terminating action). When the substrate temperature is raised from this state, the residual ethyl group is removed, and adsorption of one monolayer of Si is completed. However, if the temperature raising process takes a long time, nitrogen will be desorbed from the underlayer, and the quality of crystals will be significantly deteriorated.

However, when the substrate temperature raising process is instantaneously performed by using the above-described first embodiment or second embodiment, TES is prevented while preventing the nitrogen escape.
Since the decomposition of i is promoted, it becomes possible to highly uniformly control the adsorption amount of the dislocation suppressing substance while maintaining the crystal quality.

The above-described embodiment can be modified as described in (1) to (11) below.

(1) In the above-described embodiment, the case where the material layer forming apparatus according to the present invention is implemented as a crystal growth apparatus has been described. However, the present invention is not limited to this, and the substrate temperature is not limited to this. Various devices for forming a material layer on the substrate while appropriately changing, for example,
Of course, it may be implemented as a molecular beam epitaxy apparatus, a hydride vapor phase epitaxy apparatus, or the like.

(2) In the above embodiment, the first block 12a of the susceptor 12, the second block 12b of the susceptor 12 and the spacer 14 are made of carbon, but the present invention is not limited to this. Of course, the first block 12a of the susceptor 12, the second block 12b of the susceptor 12, and the spacer 14 may be formed of appropriate materials, for example, a refractory metal material such as tungsten, molybdenum, or tantalum. Of course good things.

(3) In the above-described embodiment, the first block 12a of the susceptor 12, the second block 12b of the susceptor 12 and the spacer 14 are formed as separate members and are connected to each other. Of course, it is not limited to the first susceptor 12.
Block 12a and second block 12b of susceptor 12
And the spacer 14 may be integrally formed, and the spacer 14 may be formed on either the first block 12a of the susceptor 12 or the second block 12b of the susceptor 12.
So as to project the spacer 14 and the spacer 14 and the first block 12a of the susceptor 12 or the second block 12b of the susceptor 12 and the spacer 14
Alternatively, the first block 12a of the susceptor 12 or the second block 12b of the susceptor 12, which is not formed to project, may be connected to each other.

(4) In the above-described embodiment, the susceptor 12 has the first block 1 via the spacer 14.
The second block 12a and the second block 12b are connected to each other with a predetermined gap between them, but the present invention is not limited to this. The first block 12a and the second block 12b may be supported with a predetermined gap. The susceptor 14 is, in short, a first block 12a having a heat capacity smaller than a predetermined heat capacity for disposing the substrate,
The second with a larger heat capacity than the predetermined heat capacity without placing the substrate
The block 12b and the block 12b are spaced apart from each other so as to have a predetermined gap, and the first block 12a and the second block 12b.
It suffices that the and are weakly thermally coupled to each other by heat radiation.

The predetermined heat capacity serving as the reference for the heat capacity of the first block 12a and the predetermined heat capacity serving as the reference for the heat capacity of the second block 12b may have the same value or different values. However, these predetermined heat capacities vary depending on the scale of the apparatus.

The predetermined heat capacity, which is the reference for the heat capacity of the first block 12a, is a heat capacity that allows the first block 12a to be rapidly heated and cooled in a desired short time.

On the other hand, the predetermined heat capacity as the reference of the heat capacity of the second block 12b may be a heat capacity capable of rapidly raising and lowering the temperature of the second block 12b in a desired short time. At the desired time (for example,
This is a time longer than the time required for the first block 12a to rapidly raise and lower its temperature. It is preferable that the heat capacity is such that the temperature can be raised and lowered by the above method.

(5) In the above embodiment, the first block 12a of the susceptor 12 and the second block 12b of the susceptor 12 are made of the same material,
By forming the block 12a in a thin plate shape and the second block 12b in a thick plate shape and forming the first block 12a thinner than the second block 12b to reduce the size, the volume of the first block 12a is reduced. Second block 12b
To make the heat capacity of the first block 12a smaller than that of the second block.
Although the heat capacity is smaller than that of the block 12b, it is needless to say that the heat capacity of the first block 12a is not limited to this.
You may make it smaller than the heat capacity of the block 12b.

In this case, if carbon is used as the material of the second block 12b, tungsten, molybdenum, tantalum or the like may be used as the material of the first block 12a.

Also in this case, the predetermined heat capacity as the reference of the heat capacity of the first block 12a and the second block 12a.
The predetermined heat capacities serving as the reference of the heat capacities of b may have the same value or different values, but these predetermined heat capacities appropriately change depending on the scale of the device. .

The predetermined heat capacity, which is the reference for the heat capacity of the first block 12a, is a heat capacity that allows the first block 12a to be rapidly heated and cooled in a desired short time.

On the other hand, the predetermined heat capacity serving as the reference of the heat capacity of the second block 12b may be a heat capacity capable of rapidly raising and lowering the temperature of the second block 12b in a desired short time, but the second block 12b. At the desired time (for example,
This is a time longer than the time required for the first block 12a to rapidly raise and lower its temperature. It is preferable that the heat capacity is such that the temperature can be raised and lowered by the above method.

(6) In the above-described embodiment, the susceptor 12 is formed as a substantially rectangular parallelepiped shape as a whole, but it is needless to say that the shape is not limited to this, and the susceptor 12 as a whole has various shapes. (For example, a substantially cubic shape, a substantially cylindrical shape, etc.) may be formed.

(7) In the above-described embodiment, the first block 12a of the susceptor 12 and the second block 12b of the susceptor 12 are made of the same material,
The thickness of the first block 12a is made smaller than that of the second block 12b by forming the block 12a in a thin plate shape and the second block 12b in a thick plate shape so as to change the respective thicknesses. By reducing the volume of the first block 12a to be smaller than that of the second block 12b, the heat capacity of the first block 12a is made smaller than that of the second block 12b. Although it is smaller than the above, it is needless to say that it is not limited to this.

That is, the first block 12a and the second block 12b have the same thickness, but the length of the first block 12a in the vertical direction and the horizontal direction is the second block 12.
By making it smaller than the length of b in the vertical and horizontal directions,
The volume of the first block 12a may be made smaller than the volume of the second block 12b so that the respective volumes are different, whereby the heat capacity of the first block 12a may be made smaller than that of the second block 12b.

Further, by making the thickness of the first block 12a and the length in the vertical and horizontal directions smaller than the thickness of the second block 12b and the length in the vertical and horizontal directions, the volume of the first block 12a is reduced. May be smaller than the volume of the second block 12b so that the respective volumes are different, and thereby the heat capacity of the first block 12a may be smaller than the heat capacity of the second block 12b.

(8) In the above-described embodiment, the spacer 12 is the first block 12a (second block 1).
2b) are arranged only on the two opposite side edges, but the present invention is not limited to this, and for example, spacers 12 are provided on the four side edges of the first block 12a (second block 12b). May be respectively arranged, or small spacers 12 may be respectively arranged at the four corners of the first block 12a (second block 12b).

(9) In the above-mentioned embodiment, the method of the eddy current induced heating method using the RF heating coil as the heating means is used, but it is needless to say that the method is not limited to this. For example, a method such as a resistance heating method may be used.

(10) In the above-described second embodiment, both the RF heating coil and the light source are provided as the heating means for the susceptor and the semiconductor wafer, but the present invention is not limited to this. And R
It is possible to provide only the light source without providing the F heating coil.

When the RF heating coil is not provided, it is not necessary to provide the RF power supply or the RF control device for controlling the RF power supply as a matter of course.

(11) The above-described embodiments and the modifications described in (1) to (10) above may be combined appropriately.

[0103]

Since the present invention is configured as described above, it is excellent in that it is possible to provide a material layer forming apparatus capable of abruptly changing the temperature of a substrate in a short time. Produce an effect.

[Brief description of drawings]

FIG. 1 is a conceptual configuration explanatory view of a crystal growth apparatus as a conventional material layer forming apparatus.

FIG. 2 is a conceptual configuration perspective view of a conventional susceptor.

FIG. 3 is a conceptual configuration explanatory diagram of a first embodiment of a material layer forming apparatus according to the present invention.

FIG. 4 is a perspective view of a conceptual configuration of a susceptor according to the present invention.

FIG. 5 is a schematic diagram showing a temperature change of a susceptor.

FIG. 6 is a conceptual configuration explanatory diagram of a second embodiment of the material layer forming apparatus according to the present invention.

FIG. 7 is an explanatory diagram showing a sequence for forming an InGaN / AlGaN-based quantum well structure.

FIG. 8 is an explanatory diagram showing a sequence when forming an Mg doping layer.

FIG. 9 is an explanatory diagram showing a sequence of supplying TESi, which is a transition suppressing substance that suppresses the threading transition of gallium nitride.

[Explanation of symbols]

10, 20, 100 Crystal growth equipment 12,108 susceptor 12a first block 12b Second block 12aa, 108a upper surface 12ab, 108b holding part 14 Spacer 22 Light source 24 ON / OFF control device 102 RF heating coil 104 Crystal growth reactor 104a gas introduction hole 104b gas discharge hole 106 semiconductor wafer 110 RF power supply 112 RF controller

─────────────────────────────────────────────────── ─── Continuation of the front page (56) Reference JP 2001-135582 (JP, A) JP 7-277885 (JP, A) JP 5-315263 (JP, A) JP 3-145123 (JP, A) (58) Fields surveyed (Int.Cl. ⁷ , DB name) H01L 21/205

Claims (7)

(57) [Claims] 1. A material layer forming apparatus for forming a material layer on a substrate while appropriately changing the temperature of a substrate placed on the susceptor by raising or lowering the temperature of the susceptor, wherein the substrate is placed. A first block having a first heat capacity smaller than a predetermined heat capacity, and a second block having a second heat capacity larger than the predetermined heat capacity in which the substrate is not arranged, and the first block. A susceptor in which a block and the second block are spaced apart from each other with a predetermined gap, and the first block and the second block are gently thermally coupled by heat radiation; and the susceptor. To individually detect the temperatures of the RF heating coil capable of heating and lowering the temperature in a pulse manner and the first block and the second block of the susceptor. Based on the detection result of the detection means, the power supply to the RF heating coil is controlled so that the RF heating coil continuously heats, and the magnitude of the heating power of the RF heating coil is pulsed. Control means for controlling power supply to the RF heating coil so as to change in magnitude, the power supply to the RF heating coil is controlled by the control means based on the detection result of the detection means, and the RF heating When the coil is continuously heated and is in a steady heating state, the first block is heated by the heat radiation from the second block of the susceptor, and the entire system is heated through the loose thermal coupling due to the heat radiation. When the output of the RF heating coil is controlled to change in magnitude in a pulse shape and the output of the RF heating coil is steeply increased in a short time, the first temperature of the susceptor is controlled. Only one block is heated earlier than the second block in a short time to steeply raise the temperature, while on the other hand, when the output of the RF heating coil is steeply decreased in a short time, the susceptor Only the first block lowers the temperature in a short time in advance by the second block to rapidly lower the temperature, and follows the switching timing at which the magnitude of the heating power of the RF heating coil is changed in a pulse manner. A material layer forming apparatus in which the temperature of the first block of the susceptor and the temperature of the substrate arranged on the first block are changed in a pulsed manner in a short time. 2. A material layer forming apparatus for forming a material layer on a substrate while appropriately changing the temperature of the substrate arranged on the susceptor by raising or lowering the temperature of the susceptor. A first block having a first heat capacity smaller than a predetermined heat capacity, and a second block having a second heat capacity larger than the predetermined heat capacity in which the substrate is not arranged, and the first block. A susceptor in which a block and the second block are spaced apart from each other with a predetermined gap, and the first block and the second block are gently thermally coupled by heat radiation; and the susceptor. And an RF heating coil capable of raising and lowering the temperature in a pulsed manner. When the RF heating coil is continuously heated and is in a steady heating state, the second heating element of the susceptor is used. The first block is heated by the heat radiation from the block, the temperature of the entire system is controlled through the loose thermal coupling due to the heat radiation, and the magnitude of the heating power of the RF heating coil changes in a pulse manner. However, when the output of the RF heating coil is sharply increased in a short time, only the first block of the susceptor is heated earlier than the second block in a short time, and the temperature is rapidly increased. On the other hand, when the output of the RF heating coil is sharply lowered in a short time, only the first block of the susceptor is preliminarily cooled by the second block in a short time to make it steep. Before the temperature of the susceptor is placed in the first block and the first block, the temperature is decreased and the switching timing for changing the magnitude of the heating power of the RF heating coil in a pulse manner is followed. A material layer forming apparatus in which the temperature of a substrate is changed in a pulsed manner in a short time. 3. A material layer forming apparatus for forming a material layer on a substrate while appropriately changing the temperature of the substrate arranged on the susceptor by raising or lowering the temperature of the susceptor. A first block having a first heat capacity smaller than a predetermined heat capacity, a second block having a second heat capacity larger than the predetermined heat capacity not disposing the substrate, and a spacer having a predetermined thickness. The first block and the second block are connected to each other via the spacer, and the first block and the second block are gently thermally coupled by heat radiation. In the case where the susceptor and the RF heating coil that heats the susceptor and can raise and lower the temperature in a pulsed manner are provided, and the RF heating coil is continuously heated and is in a steady heating state Means that the first block is heated by heat radiation from the second block of the susceptor, and the temperature of the entire system is controlled via loose thermal coupling due to heat radiation. When the magnitude changes in a pulse shape and the output of the RF heating coil is sharply increased in a short time, only the first block of the susceptor precedes the second block for a short time. When the output of the RF heating coil is rapidly decreased in a short time by being heated by the second heating block, only the first block of the susceptor is preceded by the second block. The first block of the susceptor and the susceptor and the first block are followed in accordance with the switching timing at which the temperature is rapidly decreased and the temperature of the RF heating coil is changed in a pulse manner. An apparatus for forming a material layer, wherein the temperature of the substrate arranged in the first block is changed to high or low in a pulsed manner in a short time. 4. The material layer forming apparatus according to claim 1, further comprising:
A material layer forming apparatus comprising: a light source that irradiates the first block with light to heat it. 5. The material layer forming apparatus according to claim 4, wherein the light source turns on or off in a pulsed manner. 6. The material layer forming apparatus according to claim 1, claim 2, claim 3, claim 4, or claim 5, wherein the first block and the second block are Is formed of carbon, and the volume of the first block is smaller than the volume of the second block. 7. The substance layer forming apparatus according to claim 1, claim 2, claim 3, claim 4, claim 5, or claim 6, wherein: The second block is a material layer forming apparatus in which the second block is formed of carbon, the first block is formed in a thin plate shape, and the second block is formed in a thick plate shape.