JPH0355401B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to the production of ultrathin films of high quality nitrides at lower temperatures than conventional film formation temperatures.

[Conventional technology]

(a) Conventionally, the method for forming a nitride film on the surface of a substrate is to heat the substrate to be coated to a high temperature in a reactive gas to form a nitride film on the surface of the substrate. . However, with this conventional method, very thin films, especially 5-15 Å
In order to form a nitride film on a substrate with a thickness of 100°C, the substrate had to be heated to 70-1200°C.

(b) As a conventional method for etching and cleaning the surface of a substrate, a sputter etching method using an inert gas such as argon has been known. In this method, a target is placed on one of two poles, and argon gas is accelerated between the two poles and collided with the target, and the collision energy removes dirt, oxides of the substrate, or the substrate attached to the surface of the substrate. It is a method of removing the surface part of itself.

[Problems with conventional technology]

(b) In the conventional technology shown in [Conventional technology] (a) above, when forming an ultra-thin film, the substrate temperature is
The temperature reaches 1200℃. This high temperature does not meet the requirements for manufacturing semiconductor devices, which requires that the nitride film be made extremely thin and at a low temperature.

(b) In the conventional method of etching and cleaning the substrate surface shown in [Prior Art] (b) above, the energy of argon gas is large and the removal is forcibly performed by force, so the substrate surface is It caused damage to itself, and the board was metamorphosed.

Particularly in the case of a single crystal surface, a metamorphosed layer is formed on the surface, so it is essential to heal the damage by plasma etching by annealing or the like. Therefore, the surface of this substrate does not have a single crystal surface that should be flat, and even if it was attempted to epitaxially grow a thin single crystal film on this surface, it would be impossible.

In addition, on a sputter-etched surface, the force tends to vary locally within the same target due to the physical shape of the target, and the targets that are collided with each other are clustered in the form of hundreds to hundreds of thousands of targets. The surface of the substrate was etched, and microscopically it became extremely uneven.

[Purpose of the invention]

Therefore, the present invention has the following two objectives. The first purpose is to fabricate an ultra-thin film of high quality nitride on a substrate at low temperature.

The second purpose is to prevent the presence of contamination or foreign matter that is unavoidably generated during the manufacturing process from damaging the substrate surface, which has the most physically and electrically sensitive interface, prior to the formation of this nitride film. Cleaning and etching without any hassle.

[Structure of the invention]

In order to achieve the above object of the invention, the present invention has the following configuration.

First, in order to achieve the objective of the first invention,
Nitrogen or nitride gas is chemically activated by microwave energy of 1 to 10 GHz in an induction energy supply section placed in front of the substrate, and
This film forming method is characterized by forming a nitride film of the substrate on the surface of the substrate by reacting with the substrate heated to 600°C.

Second, the invention is to achieve the second object, in which the surface of the substrate is exposed to hydrogen or a gas in which hydrogen is mixed with an inert gas, and foreign particles on the substrate are exposed to microwave energy of 1 to 10 GHz. or a step of removing oxides and cleaning/etching;
After the step, nitrogen or nitride gas and the substrate surface are chemically activated by a microwave energy supply means of 1 to 10 GHz placed in front of the substrate without exposing the substrate to the atmosphere. of
By reacting at a temperature of 200 to 600℃,
This film forming method is characterized in that a nitride film is formed on the surface of the substrate.

Since the present invention performs such extremely light cleaning, damage to the substrate is unlikely to occur during this cleaning process, and this substrate is also different from a method in which selective plasma etching is performed using halogen or the like. Therefore, as another method of the present invention, after such cleaning, the atmosphere is replaced with a nitrogenous gas consisting of nitrogen, a nitride gas such as ammonia, or a mixture gas of nitrogen and hydrogen.
- It was found that the interface level of one such film could be lowered to 1×10 ¹¹ cm ^-3 or less by causing a gas phase (reactive gas) reaction, and it was found to be ideal. .

The present invention will be illustrated below with reference to Examples.

Example 1 The following is an example of forming an ultra-thin film of high quality nitride on a substrate at low temperature.

This substrate was placed in the apparatus shown in FIG. 1 in order to form a nitride film on the thoroughly cleaned silicon substrate surface.

The apparatus shown in FIG. 1 includes an induction energy generation source 1, an activation chamber 15, flow meters 2, 4, 6, a nitride gas inlet 3 such as ammonia, a hydrogen inlet 5, a mixer 16,
It consists of a reactor 14, a substrate heating device 8, a boat 9, a substrate 10 having a surface to be cleaned and etched, a needle valve 11, a stop valve 12, and a rotary pump 13. The reactor 14 of this device has a diameter of 5 to 30 cm, and even though its length is nearly 5 m, the distance between the activation chamber 15 where induction energy is added and the place where the substrate 10 is installed is 1 m.
As mentioned above, even when the distance was 2 to 4 meters, the plasma state of the plasma gas was sufficiently maintained.
The substrate was placed at least 3 cm, preferably 5 to 20 cm, from the inner wall of the reactor 14 to reduce the influence of the reaction tube.

Here, in order to uniformly form a coating on each part of the substrate in front of and behind the reaction source, the substrate may be arranged parallel to the flow of the reactive gas.

In this example, nitrogen was added to the hydrogen atmosphere for 10
Introduce from 7 or 6NUP to a concentration of ~40%
Ammonia with a purity of 3 was introduced from 3.

After that, microwaves of 2.45 GHz are generated as induction energy at a power of 1 to 10 W to increase the ionization rate in the activation chamber 15 and the kinetic energy of the nitrogen atoms turned into plasma, thereby forming a silicon nitride film. did. Further, the degree of vacuum in the reactor 14 was sufficiently reduced to 0.001 to 1 torr. In this case, if the power of the microwave is increased, the kinetic energy of the nitrogen atoms turned into plasma becomes too high, and the influence of the sputtering effect increases and damage to the substrate cannot be ignored.

As a result of the above, 2 to 20 Å with few dense interface states.
We were able to create a nitride film with a thickness of 200 to 600℃. For example, if an electromagnetic wave with a frequency of 500 KHz is used as the induction energy to be applied, the frequency is approximately 1/5000 of the above-mentioned 2.45 GHz microwave, so the ionization rate of ammonia molecules is also 10 ^-2 compared to that of the microwave. ^-9 and 1/10 ⁷ , and the formed film looks rough under an electron microscope. The reason for this is that 500KHz electromagnetic waves do not have enough induction energy.

Conventional technology heats the substrate to 700-1200℃,
The thermal energy alone chemically activated the ammonia molecules. However, in the present invention, ammonia molecules are first chemically activated using microwave induction energy, and this activated reaction gas is further activated using thermal energy at 200 to 600°C. Therefore, the combination of 500 KHz electromagnetic wave energy and 200 to 600°C thermal energy does not sufficiently activate the ammonia molecules in the reaction gas. Furthermore, if the power of the electromagnetic waves is increased in an attempt to give energy to the reaction gas using only the energy of the electromagnetic waves, the influence of the spatter effect on the substrate becomes a problem. Therefore, using microwaves as in the present invention, which can give sufficient activation energy to the reaction gas even with a weak power of 10 W or less and has less sputtering effect, can reduce the substrate temperature to 200-600°C, compared to the conventional 700-1200°C. It is preferable to keep the temperature lower than ℃ and to obtain an ultra-thin chambered film of good quality.

Example 2 In this example, by cleaning the semiconductor surface, a very thin film (typically
The purpose is to form a nitride film with a thickness of 25 Å or less, particularly 5 to 15 Å) at a low temperature.

The semiconductor substrate may be single crystal, or may have a polycrystalline, amorphous or semi-amorphous structure.

Further, if a semiconductor is formed on an insulating or conductive substrate and the uppermost surface thereof is a semiconductor, such a composite substrate may be used as the substrate.

Semiconductors include silicon, germanium, gallium arsenide, boron phosphide, gallium arsenide,
It was applied to compound semiconductors such as aluminum.

First, the process of cleaning the semiconductor surface will be explained.

In this example, silicon was used to easily demonstrate the effect.

Conventionally, it was thought that natural oxide (hereinafter abbreviated as NO) was generally formed on the silicon surface. This no. time of exposure to air or
It is also affected by RH (relative humidity), and the film that is formed is porous and locally has a thickness of 5 to 20 mm.
It varied by Å. However, the inventor has discovered that this N.
O. is formed after a while after the substrate is left in the air, and within 1 hour after cleaning with a hydrofluoric acid solution, a stain film of 5 to 20 Å, which is a mixture of hydrogen, fluorine, silicon, etc., is formed. It was found that it was formed thickly.

In other words, when the surface of a semiconductor substrate, especially a silicon substrate, is cleaned by a conventionally known method, the surface
Very thin oxides of ~30 Å, such as natural oxides, have been postulated to exist. However, as a result of precise surface investigation using an ellipsometer, etc.,
It was found that a stain film was formed on the surface, which was immovable to an acidic solution made of a mixture of silicon, fluorine, and boron. This 5-20 Å stain film easily reacts with air even at room temperature, and when left for 1-10 hours, an oxide, such as natural oxide, is formed as if the substrate surface had been oxidized.

In the present invention, the stain film, which is a passive film that is easily oxidized, is made of silicon hydrogen, fluoride (SiF ₄ ,
H ₂ SiF ₄ , SiH _{4 ,} etc.) and vaporizes and disappears, resulting in an extremely clean substrate surface.

In this example, in order to make such a stain film homogeneous and to eliminate the reaction of this film with air at room temperature, the surface was coated with hydrofluoric acid:water = 1:10 to 1:100.
to remove NO. At the same time, a stain film (which is colorless because it is extremely thin, but abbreviated as stain film because the components are homogeneous) was formed on this surface. Furthermore, it was washed with pure water and dried in nitrogen.

Thereafter, the substrate was placed in the apparatus shown in FIG.

The apparatus shown in FIG. 1 includes an induction energy generation source 1, an activation chamber 15, flow meters 2, 4, 6, a nitride gas inlet 3 such as ammonia, a hydrogen inlet 5, a mixer 16,
It consists of a reactor 14, a substrate heating device 8, a boat 9, a substrate 10 having a surface to be cleaned and etched, a needle valve 11, a stop valve 12, and a rotary pump 13. The reactor 14 of this device has a diameter of 5 to 30 cm, and even though its length is nearly 5 m, the distance between the activation chamber 15 where induction energy is added and the place where the substrate 10 is installed is 1 m.
As mentioned above, even when the distance was 2 to 4 meters, the plasma state of the plasma gas was sufficiently maintained.
The substrate was placed at least 3 cm, preferably 5 to 20 cm, from the inner wall of the reactor 14 to reduce the influence of the reaction tube.

The inductive energy source 1 is 1~10GHz, e.g.
A 2.45 GHz microwave may be used, and an energy of 1.0 to 100.0 W was sufficient. For such a reaction system, the thin stain film described above is
The material, which had been formed with a film thickness of 1.5 Å, was placed as shown in Figure 1. Then rotary pump 1
3, the reactor was evacuated to a pressure on the way to 10 torr. Then add hydrogen from 5 to 10 to 1000
cc/min was introduced. This hydrogen has a purity of 5N or higher, especially
8N or more was used.

When cleaning the substrate simply by heating without adding induction energy, a mixed gas may be created by mixing an inert gas such as He or Ar at a flow rate of 50 to 90% compared to hydrogen. . In other words, the substrate surface is cleaned and etched by exposing it to hydrogen or an activated gas containing hydrogen and an inert gas, such as Ar or He at a flow rate of 0.5 to 50%, to remove impurities and other foreign substances on the surface. Furthermore, locally generated oxides may be removed. Therefore, hydrogen was similarly introduced from 5 at a flow rate of 5 to 500 c.c./min.

The pressure inside the reactor is 0.001 to 760 torr, and if microwave energy is used, for example, 2.45 GHz.
It is 0.001~0.1torr. Furthermore, when simply heating and reducing without adding induction energy, 10 to 760 torr was suitable. Cleaning takes 15 to 50 minutes and takes 10 to 30 minutes. Thereafter, the substrate was left in a reducing atmosphere.

The cleaning/etching process of the present invention is performed using hydrogen and does not cause any damage to the substrate surface. Therefore, this hydrogen has the effect of gasifying dirt or oxides on the surface as hydroxyl groups, and semiconductors generated due to the removal of dirt. The effect of neutralizing the unpaired bonds on the outermost surface by bonds such as Si-H, and the effect of this active hydrogen flowing into the substrate and neutralizing the unpaired bonds in the substrate make active unpaired bonds It goes without saying that the contribution to the disappearance of the hand or the recombination center is large.

In this example, hydrogen gas for cleaning was not turned into plasma. However, it may also be chemically activated by inductive energy. However, in that case, in order to prevent the sputtering effect of this activated hydrogen on the substrate surface, at 13.56MHz, 0.5 to 50 W at 0.1 to 5 torr was applied.
Even though the power was set to low, damage was observed to a depth of 20 to 30 Å below the interface. But 2.45GHz
As a result of using 0.05 to 50 W at 0.001 to 0.1 torr, especially 1 to 5 W, the ionization rate was 13.56 MHz.
10 ^-7 , it is 10 ^-2 , which is 10 ⁵ times larger, and since the power is small, the depth of damage caused by the sputtering effect can be sufficiently reduced to 0 to 5 Å. Also, when microwaves are used, the degree of vacuum is low, so the amount of hydrogen used is 10 ~
It was 50c.c./min, 1/300 of this example.

In this example, silicon was used, but similar effects were also observed in germanium, gallium arsenide, and the like.

In this example, 100% hydrogen was used. However, in order to prevent the possibility of hydrogen explosion during use, an inert gas such as argon gas may be introduced from FIG. 17 to dilute the hydrogen.

The present invention is essentially different from a sputter etch method, and is also essentially different from a plasma etch method that uses a sputter effect in conjunction with a reactive gas such as a halide gas such as CCI ₄ ; Another feature is that it does not use

The above is the cleaning process.

Next, as a step after cleaning, a nitride film was formed on the substrate surface as described in Example 1.

The results of experiments conducted to enhance the effects of the present invention will be shown below.

Figure 2 shows that after cleaning the substrate surface, it is nitrided at 500℃ using ammonia gas with a purity of 6N or higher.
It is a graph showing the relationship between the cleaning time and the nitrided film pressure when cleaning was performed for 30 minutes and the cleaning temperature was changed.

The drawing shows the case where no induction energy is given,
Solid curves 20 to 23 are 400℃, 700℃, respectively.
The substrates are shown cleaned by exposing them to hydrogen at 1000℃ and 1200℃. According to the drawing, in order to make a nitride film with a thickness of 5 to 15 Å, the cleaning temperature should be set to 700 Å.
It has been found that heating to ~1200°C, especially 900-1100°C is sufficient. This is considered to be related to the etching of the stain film mentioned above. In other words, the graph shown in Figure 2 shows that the higher the etching temperature, the more a stain film with a thickness of 5 to 20 Å is removed, and the thickness of the nitride film formed by subsequent nitriding becomes thinner. It shows that it will happen.

When etching a stain film using hydrogen, increasing the etching temperature increases the effect because the hydrogen molecules are activated by thermal energy. Therefore, a high etching effect can also be obtained by activating hydrogen molecules using this thermal energy using microwave induction energy.

Activating hydrogen molecules and increasing the etching effect by using microwaves in this way solves the problem of temperature, which is a problem when manufacturing semiconductor devices, as shown in [Problems with the Prior Art] (a) and (b). This solves the problem of spatter effect.

From the above, it can be seen that the cleaning using hydrogen and microwave according to the present invention is extremely important in producing a chemically stable silicon nitride film with a film thickness of 5 to 20 Å.

Nitriding after this cleaning should be done at 80°C instead of 500°C.
℃, the film thickness was 5 to 8 angstroms thinner than that at 500 ℃, and even at 1100 degrees Celsius, it was only 4 to 7 angstroms thinner. However, in order to make a dense silicon nitride film,
Production at 800-1100°C was preferred.

When attempting to produce a thin silicon nitride film by heating alone in this manner, stable silicon nitride acid could not be produced unless the film was heated to a high temperature.

However, when microwaves (2.45GHz) with less sputtering effect are applied at a weak power of 0.1 to 10W,
A similar dense nitride film with a thickness of 2 to 20 Å with few interface states could be made at 200 to 600°C. In other words, to create ultra-thin films, instead of using low-frequency induction energy,
Only a method of thermal nitriding, in which microwaves are applied with the apparatus of FIG. 1 or, conversely, is not applied at all, was preferred, since the sputtering effect is small.

As is clear from the above explanation, as a result of adopting the cleaning etching structure of the present invention, problems such as contamination of the substrate, presence of foreign matter on the substrate, and cleaning of the substrate can be avoided when forming an ultra-thin film on the substrate. By the method shown in Example 1, a nitride film with a thickness of 2 to 20 Å with few dense interface states is formed on the extremely clean substrate surface obtained by the present invention. It could be made at ~600℃.

The present invention is extremely important for making a silicon nitride film with an extremely thin film thickness of 2 to 20 Å free from pinholes and having few interface states. This was extremely important for the production of solar cells.

In the present invention, the thickness of the nitride film determined by the changed nitriding atmosphere is controlled by changing the atmosphere in the next step without exposing the cleaned and etched surface to the atmosphere. It is formed in a state in which the

〔Effect of the invention〕

As shown in Example 1, by adopting the configuration of the present invention, a high-quality, ultra-thin film can be formed on a substrate at a lower temperature (200-600°C) than the substrate temperature (700-1200°C) in the conventional technology. A thick nitride film could be formed.

In addition, by adopting the configuration shown in Example 2, the presence of contamination or foreign matter that is unavoidably generated during the manufacturing process on the substrate surface, which has the most physically and electrically sensitive interface, can be prevented from damaging the substrate surface. It is possible to clean and etch the substrate without exposing it to temperature (700 to 1200℃) in conventional technology.
Because the film can be formed at a lower temperature (200 to 600°C) than the previous method, it was possible to form a high-quality nitride film with no pinholes and few interface states.

For reference purposes, the effects of using microwaves will be explained below using experimental examples.

In this experimental example, an attempt was made to form a relatively thick nitride film of 50 to 250 Å on the surface of a semiconductor.

The semiconductor substrate on which the nitride film was formed and the device were the same as in the example.

To form a film, it was immersed in a hydrogen peroxide solution (50 to 100°C) in the same manner as in the examples to form a film of 20 to 40 Å of a compound (mixture) of silicon oxide and silicon hydroxide on the surface. After that, it is purified and then diluted with hydrofluoric acid: hydrogen = 1:10 to 1:100.
Such oxides were eluted with HF solution, and at the same time a stain film was formed on the same surface. It was further purified and then dried under nitrogen.

A sufficiently clean substrate that had undergone such treatment was used. After this, a stain film (5 to 50
Å) in hydrogen as in the example.
It was heated to 600-1250°C to reduce and remove it.

In order to generate such a removed active substrate surface, in this embodiment, in addition to heating, induction energy 1
was applied at 100 to 10,000 W to activate hydrogen in the activation chamber 15. At this time, Ar or
An inert gas such as He may be introduced to simultaneously activate the gas and enhance the removal effect by its sputtering effect.

In this example as well, in order to reduce the levels at the interface between the semiconductor substrate and the film formed on its upper surface, the damaged surface is annealed at the same time during cleaning (plasma cleaning in this example). At temperature, that is, silicon
Temperatures above 800°C, particularly 1000-1200°C, had extremely important effects.

After this plasma cleaning, nitrogen was introduced into the atmosphere at a concentration of 10-40% at 7 points, or ammonia at a purity of 6 NUP was introduced at 3 steps.

After this, a 2.45 GHz microwave is applied as induction energy with an output 10 to 1000 times higher than in the example to increase the ionization rate in the activation chamber and the kinetic energy of the plasma nitrogen atoms, and heat the nitridation of the substrate. A thick silicon nitride film was fabricated using both chambering and sputtering effects simultaneously. In order to increase this kinetic energy, the degree of vacuum in the reactor 14 was also sufficiently reduced to 0.001 to 1 torr.

Figure 3 shows the temperature of the board at 900℃, 1000℃, and 1100℃.
The relationship between the nitriding time and the obtained film thickness is shown. In the drawing, curve 30 is 900℃, output
This is the characteristic when the power was set to 10W, and a film up to about 30 Å could only be obtained. In addition, since it is turned into a plasma, the interface state at the interface increases by 3× due to the sputter effect.
10 ¹¹ /cm ^-2 However, application to microelectronics was not always convenient.

Curve 31 is the result at 1000℃ and 300W, and 50
Since we were able to obtain a film thickness of at least 1.5 Å, we were able to obtain insulation properties sufficient to prevent tunneling current. The heating temperature of the substrate 10 by the heater 8 is 1000°C
This has the effect of simultaneously annealing damage caused by sputtering, and the interface level is 0.5.
~1×10 ¹¹ cm ^-2 could be obtained, making it possible to apply it to gate insulators for integrated circuits.

Extension 32 has a temperature of 1100℃ and an output of 1KW.
The annealing effect is sufficient and the temperature is high, so
For the fabrication of ~300 Å silicon nitride films by solid-vapor phase reactions, we were able to create extremely thick films with an extremely ideal interface state of 1-5×10 ¹⁰ cm ^-2 for the first time.

Curve 33 has a frequency of 500KHz and its output is
It is 1KW. In this case, since the frequency is about 1/5000, the ionization rate of ammonia molecules is also 10 ^-9 , which is 1/10 ⁶ compared to the microwave's 10 ^-2 , and the formed film cannot be seen under an electron microscope. rough. The surface has irregularities of 20 to 100 Å due to the sputter effect, and as a result, the apparent surface area becomes large, and the film quality as a gate insulator for MIS.FET has an effective transfer rate of 1/3 to 1/5 of curve 32. It has dropped to .

That is, the silicon nitride film is used as an insulating layer with a sufficient
It is made to a thickness of 250 Å, and the film quality is such that the interface is microscopically flat, the interface level is 1×10 ¹⁰ cm or less, and the pinhole density is 10 holes/cm ² or less. In order to do this, the frequency should be a high frequency of 1 GHz or higher, for example 2.45 GHz, and in order to remove the spatter effect during nitriding of the substrate, the vacuum should be high at 0.001 to 1 torr, and the output should be 100 W or more.
In order to achieve a high output of 10KW and to eliminate interface states caused by spatter between the formed film and the substrate, the temperature of the substrate was set to 800℃ or higher, especially 1000 to 1200℃.
It was extremely important to do so. Further, this reactive ionized gas may be further thickened by applying a DC electric field between the object to be nitrided and the plasma atmosphere, and also using the effect of anodization.

Alternatively, the degree of nitridation may be increased by pinching the plasma using a magnetic field to further improve the density.

Further, residual silicon oxide may be present in the silicon nitride film formed in the present invention.

In the reactor, water or chlorofluorocarbon was introduced into the outer wall of the activation chamber through 17 and led out through 18 to maintain the temperature of the activation chamber between -30° C. and room temperature. Further, the reactor core tube of the reactor 14 heated by the heater 8 was made of polycrystalline silicon, and the inner wall thereof was formed with silicon nitride to a thickness of 200 to 500 Å, or a silicon nitride core tube was used. The boat 9 that holds the substrate was also made of the same material as the reactor core tube to prevent damage to the boat from spatter and to prevent flying objects from adhering to the surface of the substrate.

Nitrogen activated in this manner sputtered the wall surface of the core tube or the activation chamber, and prevented it from being mixed in clusters into the coating on which the quartz tube was formed on a portion of the wall surface.

This experiment is extremely effective for applications such as IG.FET (insulated gate field effect transistor), DIS.FET (depression layer control field effect transistor), MIS or double MIS type photoelectric conversion devices, and solar cells. It was spot on.

In this experimental example, it goes without saying that the substrate is not limited to single crystal silicon, but any semiconductor, conductor, or insulator shown in the experimental example can be used.

In this example, the substrate was placed parallel to the flow of reactive gas. This is to form a uniform film on each part of the rear substrate in front of the reaction source of the film being formed.If the film is perpendicular to the silicon, the surface will have a thick nitride wall against the flow, and the back surface will have a thin wall. However, it was not necessarily desirable.

[Brief explanation of drawings]

FIG. 1 shows an outline of a film forming apparatus for carrying out the present invention. FIG. 2 shows the film thickness characteristics of a silicon nitride film when hydrogen cleaning and thermal nitridation according to the present invention are performed. FIG. 3 shows the relationship between the film thickness and the nitriding time in plasma nitriding using microwaves.

Claims (1)

[Claims] 1. Nitrogen or nitride gas chemically activated by microwave energy of 1 to 10 GHz in an induction energy supply section placed in front of the substrate.
A method for forming a film, comprising forming a nitride film of the substrate on the surface of the substrate by reacting with the substrate heated to 200 to 600°C. 2. The method for forming a film according to claim 1, characterized in that the surface of the substrate on which the nitride film is formed is arranged parallel to the flow of the reactive gas. 3. A step of cleaning and etching the substrate surface by exposing it to hydrogen or a gas containing hydrogen mixed with an inert gas and removing foreign substances or oxides on the substrate using microwave energy of 1 to 10 GHz, and after this step. , the surface of the substrate is heated to 200 nm with chemically activated nitrogen or nitride gas by a microwave energy supply means of 1 to 10 GHz placed in front of the substrate without exposing the substrate to the atmosphere.
A method for forming a film, comprising forming a nitride film on the surface of the substrate by reacting at a temperature of ~600°C.