JPH0621049A - Method and apparatus for forming insulating thin film - Google Patents

Abstract

PURPOSE:To realize formation of an insulating thin film of high quality containing oxygen and nitrogen with high reliability by mounting a semiconductor substrate in an atmosphere filled with predetermined gas, holding the atmosphere with the gas to a predetermined water content concentration of a special value or less, and heating the substrate to a predetermined temperature. CONSTITUTION:An insulating thin film containing oxygen and nitrogen of an element having a structure which has the film is formed on a semiconductor substrate 14. In such a case, the substrate 14 is installed in an atmosphere filled with predetermined gas. Then, the atmosphere is held with the gas in a predetermined water content concentration of about 100ppm or less, and the substrate 14 is heated to a predetermined temperature. Then, the atmosphere is held with gas containing oxygen or nitrogen as a material of the film to a predetermined water content concentration of about 100ppm or less to form the film. The atmosphere is filled with the gas, and the substrate 14 is cooled to a predetermined temperature lower than the heating temperature of the substrate 14 in the atmosphere.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for forming an insulating thin film of a semiconductor device, and in particular, it is performed in a gas atmosphere containing oxygen and nitrogen, which is a raw material of the insulating thin film, from which water is removed. The present invention relates to a thin film forming method and a thin film forming apparatus.

[0002]

2. Description of the Related Art Generally, MOS (metal ox) using Si is used.
As a gate insulating film material for a structural element, a Si oxide film, a Si oxynitride film (hereinafter referred to as an ON film), or the like is used. In particular, the latter is in the film compared to the former. -Si dangling bonds (unbonded hands) at the interface can be effectively inactivated (passivated) by N, and improvement of device characteristics such as hot carrier resistance can be expected. As such an ON film forming method, usually, a method of heating a Si substrate in a source gas atmosphere containing oxygen and nitrogen at atmospheric pressure with a resistance heating electric furnace or an infrared irradiation heating device is mainly used.

In recent years, the miniaturization and high performance of MOS structure elements have been actively promoted, and as a result, the ON film for gates has come to use a thin film having a Si oxide film equivalent film thickness of 10 nm or less. And uniform film quality with good interface
The insulating thin film forming step of forming a gate insulating thin film having a large film thickness is an extremely important step for realizing the device having high reliability and high performance. When such a thin film is formed by the above-mentioned method which is most frequently used in the prior art,
Since the moisture concentration in the atmosphere in the processing chamber where the oxidation and nitriding reactions are performed is usually as high as about 200 to 500 ppm or more, O
Si-H or Si- in the interface between N thin film and substrate or in ON thin film
Excessive bond states such as OH and N—H bonds are generated,
In addition, a point defect (Si dangling bond, etc.) is formed by the detachment of the bonding atom with Si, etc., and further, oxidation /
There was a practically very serious problem that the nitriding speed fluctuated and the thickness of the ON thin film eventually became non-uniform.

In order to reduce the water concentration in the processing chamber, few devices have a substrate exchanging chamber for shutting off the processing chamber from the outside air, and the provisional substrate exchanging chamber is provided. However, it is configured for the purpose of simply shutting off the mixture of outside air, and for the purpose of actively removing the moisture originating from the outside or adhering to the substrate or the substrate fixing device. There wasn't. Therefore, even if a low-moisture gas is introduced into the processing chamber, the concentration of water in the atmosphere inside the processing chamber may be increased due to the intrusion of moisture into the processing chamber due to being caught from the outside air, the moisture adhering to the substrate, the substrate fixing device, or the like. Increased and fluctuated. Moreover, in order to realize the thinning of the average thickness of the ON thin film with good reproducibility, it is necessary to lower the oxidation rate, that is, lower the oxidation temperature. In view of the above point, this was not achieved even though there was an optimum oxidation temperature range, and it was extremely difficult to form the best ON thin film.

Due to the defects of the ON thin film, the non-uniformity of the film thickness, and the restriction of the oxidation temperature range as described above, the generation of hot carriers and interface states causing deterioration of the electrical characteristics of the MOS structure element over time. There is a very serious problem in practical use that it is difficult to form an insulating thin film for a gate, which has a low frequency and a low carrier trap density and a small film thickness variation.

[0006]

As described above, according to the prior art, since the formation of the ON thin film is carried out under a gas atmosphere containing oxygen and nitrogen having a high water concentration of atmospheric pressure, that is, 1 atm, the ON thin film and the substrate are not formed. Lattice defects and bonding states other than the purpose due to this moisture are formed at the interface with and in the ON thin film, and the film thickness varies with the difference in the water concentration on the substrate. In order to ensure reproducibility, there are obstacles such as restriction on the oxidation temperature,
Due to the deterioration of the film quality and the non-uniformity of the film thickness due to these factors, the generation of hot carriers near the interface, the increase of the trap amount, the increase of the local electric field intensity, etc. occur, and thus the electrical characteristics of the MOS structure element with time elapse. It was difficult to realize a highly reliable element because the change characteristics and the withstand voltage characteristics deteriorated.

The present invention has been made in view of the above problems, and an object of the present invention is to provide an insulating thin film forming method and a forming apparatus which can reliably form a high quality insulating thin film. To provide.

[0008]

SUMMARY OF THE INVENTION The present invention solves such a problem by forming an ON thin film at about 100 p.
In an atmosphere of extremely low water concentration of pm or less, or about 1
Extremely low water concentration of less than 00ppm and about 750T
In a depressurized atmosphere below orr, or about 100 pp
By carrying out in an atmosphere in which a gas containing oxygen and nitrogen, which is a raw material of an insulating thin film and has an extremely low water concentration of m or less, is diluted with a neutral gas such as pure nitrogen or an inert gas such as argon, In addition to reducing the interface between the ON thin film and the substrate and the defect density in the ON thin film,
By improving the uniformity of the film thickness and expanding the temperature increase limit range of the oxidation temperature, the film quality and reliability of the ON film and the consistency between the ON film and other films are improved.

That is, the first step of installing the semiconductor substrate in an atmosphere filled with a predetermined gas, and maintaining the atmosphere at a predetermined water concentration of about 100 ppm or less with the predetermined gas, or the atmosphere is predetermined. About 750To of gas
The pressure is maintained at a predetermined pressure below rr and the atmosphere is maintained at about 100
A second step of heating the semiconductor substrate to a predetermined temperature while maintaining a predetermined water concentration of ppm or less, and a predetermined water content of about 100 ppm or less in a gas containing oxygen or nitrogen, which is a raw material of the insulating thin film, in the atmosphere. The concentration is maintained, or the atmosphere is maintained at a predetermined pressure of about 750 Torr or less with a gas containing oxygen or nitrogen that is a raw material of the insulating thin film, and the atmosphere is maintained at a predetermined water concentration of about 100 ppm or less, or The atmosphere is a mixed gas of a gas containing oxygen or nitrogen, which is a raw material of the insulating thin film, and a neutral gas such as pure nitrogen or an inert gas such as argon, and is about 100.
A third step of forming the insulating thin film while maintaining a predetermined water concentration of ppm or less, and after forming the insulating thin film in the third step, the atmosphere is filled with a predetermined gas, and the atmosphere is filled with the predetermined gas. A fourth step of cooling the semiconductor substrate to a predetermined temperature lower than the heating temperature of the semiconductor substrate is used to form an insulating thin film.

[0010]

The present invention forms an ON thin film in an atmosphere having an extremely low water content, in an atmosphere having a very low water content and under reduced pressure, or with oxygen and nitrogen as a raw material of an insulating thin film having an extremely low water content. By carrying out in an atmosphere in which the gas containing is diluted with a neutral gas such as pure nitrogen or an inert gas such as argon, the defect density in the interface between the ON thin film and the substrate and the ON thin film is reduced,
Since the film quality and reliability of the ON film and the consistency between the ON film and other films can be improved by the uniformity of the film thickness and the extension of the temperature rise limit range of the oxidation temperature, the MOS structure element can be improved. It is possible to realize a highly reproducible element with high reproducibility, which is capable of preventing deterioration of the characteristics of the electric characteristics with time and the like.

[0011]

EXAMPLE As an example of the present invention, M using a Si substrate
Among the OS diode forming steps, the ON thin film forming step for a gate will be taken as an example to describe the method of forming an insulating thin film and the configuration of the forming apparatus of the present invention. In the embodiment, as a method of loading and unloading the substrate of the ON thin film forming apparatus, it is possible to transfer the substrate without contacting the inner wall of the processing chamber (soft landing).
The forming method and the device configuration will be described by taking the case of adopting as an example.

FIG. 1 is a schematic diagram showing an embodiment of an insulating thin film forming apparatus according to the present invention. In the figure, 1
Is a processing chamber, 2a and 2b are moisture removers, 3 is a heating unit, 4 is a processing chamber gas introduction system, 5 is a processing chamber exhaust system, 6 is a processing chamber opening / closing unit, 7 is a substrate exchange chamber, and 8 is substrate exchange. Room gas introduction system,
9 is a substrate exchange chamber exhaust system, 10 is a telescopic tube, 11 is a substrate transfer drive unit, 12 is a substrate fixing base support unit, 13 is a substrate fixing base, 14 is a substrate, 15 is a baking heater wire, and 16 is an expanding / contracting direction. Is.

The processing chamber 1 has a heating section 3, a processing chamber gas introduction system 4, a moisture remover 2a, and a processing chamber exhaust which can control the processing temperature, the type and flow rate of gas, the moisture concentration in gas, and the exhaust speed. It has a system 5 and can be set to required conditions. Further, a processing chamber opening / closing unit 6 for preventing the entry of outside air and maintaining the indoor atmosphere is provided at the end portion thereof, and is connected to the substrate exchange chamber 7 while maintaining airtightness. The substrate exchange chamber 7 has an opening / closing door (not shown) for loading / unloading the substrate from the outside, and in order to realize a required atmosphere, the type and flow rate of gas, the moisture concentration in gas, and the exhaust speed are controlled. It has a substrate exchange chamber gas introduction system 8, a moisture remover 2b, and a substrate exchange chamber exhaust system 9. Further, a telescopic tube 10, which is a mechanism for transferring a substrate, a substrate transfer driving unit 11, a substrate fixing base support unit 12, and a substrate fixing base 13 are connected to the end portion of this.
That is, the substrate 14 installed on the substrate fixing base 13 is replaced by the movement of the substrate transfer driving unit 11 connected to the substrate fixing base support unit 12 (in the figure, the substrate 14 can be moved in the lateral direction such as the expansion / contraction direction 16). It can be moved between the chamber 7 and the processing chamber 1, and can be installed in the processing chamber 1 together with the substrate fixing base 13. At the time of this movement, the expansion tube 10 is moved by the substrate transfer drive unit 1.
With the movement of 1, the expansion and contraction can be performed without destroying the atmosphere of the substrate exchange chamber 7. In addition, the water removers 2a, 2
b is the required extremely low water concentration (for example, about 10 ppb
The following) gas can be supplied. In addition, a bake heater wire 15 for removing moisture heating in the wall is installed around the substrate exchange chamber 7 and the expansion tube 10.

As described above, the atmosphere of the processing chamber 1 and the substrate exchange chamber 7 can be controlled independently of each other.
Has an apparatus configuration capable of advancing the insulating thin film forming step in an atmosphere having an extremely low water content while completely cutting off contact with the atmosphere.

Here, as a gate ON thin film forming step in the Si-MOS diode forming step, a Si substrate patterned by an insulating thick film such as a Si oxide film or a nitride film so as to insulate regions other than the diode operating region. A thin ON thin film (for example, 5 nm (hereinafter, referred to as Si oxide film equivalent thickness)) is formed on the exposed surface (diode operating region) by supplying a gas containing oxygen and nitrogen and by thermal diffusion / oxidation / nitridation reaction. The first example of the method for forming an insulating thin film in the low-moisture atmosphere of the present invention will be outlined while showing the method of using the device of the present invention by taking the above-mentioned forming process as an example.

In the substrate exchange chamber 7 in which the substrate 14 having the patterned exposed portion of the Si substrate is filled with a neutral gas such as N ₂ which does not adversely affect Si or an inert gas such as Ar. After being installed on the substrate fixing base 13 of FIG. 1, the gas is exhausted to a vacuum chamber (for example, about 10 ⁻⁶ Torr or less), and the inner wall of the baking heater wire 15 is heated for a required time (for example, about 80 to 200 ° C.). Then, the water concentration in the atmosphere is reduced and the cleanliness is improved (first preliminary step). The processing chamber 1 is also evacuated to a high vacuum in advance, and the inner wall of the processing chamber 1 is heated by the heating unit 3 (for example, about 700 to 1200 ° C.) to form a clean atmosphere having a low water content (second preliminary step). The residual moisture concentration in the substrate exchange chamber 7 is equal to or lower than the required moisture partial pressure (for example,
(Approx. 10 ⁻⁸ Torr or less), after introducing the above-mentioned neutral gas or inert gas until the pressure becomes the same as the processing atmosphere in the processing chamber 1, the processing chamber opening / closing part 6 is opened.
Is transferred to the processing chamber 1 (first step). Incidentally, the processing room 1
Also, when the same low moisture pressure as the atmosphere of the substrate exchange chamber 7 is reached, the neutral gas or the inert gas is introduced to the required temperature (the moisture concentration at this time is about 100 to 1 pp).
m or less). After the transfer, the processing chamber opening / closing part 6 is closed, and while the appropriate amount of the neutral gas or the inert gas is introduced into the processing chamber 1, the processing chamber 1 is simultaneously evacuated to a required pressure (for example, about 2000-0.1 Tor
The substrate 14 is heated to a required oxidation / nitriding temperature (for example, about 700 to 1200 ° C.) while being kept at r) (second step). At the time when the required oxidation / nitriding temperature is reached, oxygen or nitrogen containing, for example, O ₂ , NH ₃ , N ₂ O, etc. is contained in place of the neutral gas or inert gas introduced into the processing chamber 1. While the gas is introduced into the processing chamber 1 at a required concentration and flow rate, the gas is simultaneously exhausted in some cases, and the pressure inside the processing chamber 1 is reduced to a required pressure (for example, about 2000 to 0.1 Torr).
By holding at r), an ON thin film is formed on the exposed surface of the Si substrate by thermal diffusion reaction (third step).
As the ON thin film forming procedure in the third step, the ON film composition may be formed from the beginning, or post-oxidation nitriding or post-nitridation oxidation may be performed. When the required film thickness is reached, the introduction of the raw material gas is stopped, the neutral gas or the inert gas is introduced into the processing chamber 1 instead, and the inside of the processing chamber 1 is filled with this gas. Then, the substrate 14 is cooled to a temperature (for example, about 600 ° C. to around room temperature) that does not interfere with the next step (generally, the gate electrode forming step) (fourth step).
Process). The cooling is performed in the substrate exchange chamber in which the substrate 14 is in a gas atmosphere equivalent to the atmosphere in the processing chamber 1 when the inside of the processing chamber 1 is replaced with the neutral gas or the inert gas after the film formation. It is possible to obtain the ON thin film for a gate in the same low moisture concentration atmosphere by returning to 7 and closing the processing chamber opening / closing part 6 and then cooling to the above temperature.

As described above, by carrying out the method of forming an insulating thin film in a low moisture concentration atmosphere of the present invention, the gas supply amount can be arbitrarily controlled in a constant low moisture concentration atmosphere in which the film formation rate does not become non-uniform. Therefore, it was possible to realize an extremely thin (for example, 5 nm or less) gate ON thin film on the exposed portion of the Si substrate surface of the substrate 14 at a required oxidation / nitriding temperature with excellent controllability and reproducibility. Moreover, because of the treatment under ultra-low moisture,
The quality of the insulating thin film itself, which is important for such ultra-thin films, and the interface characteristics between the insulating thin film and the substrate were improved, and charge accumulation in the gate insulating film, which is a factor in deterioration of the characteristics over time, was reduced or suppressed. . The results described here are merely one example of the effectiveness of the present invention, and at the required temperature for carrying out the present invention,
Moreover, since the adverse effect of moisture in the atmosphere can be suppressed almost completely, a high-quality insulating thin film can be realized with high reliability.

A second example of the method for forming an insulating thin film in a low moisture atmosphere of the present invention will be outlined.

In the substrate exchange chamber 7 in which the substrate 14 having the patterned Si substrate exposed portion is filled with a neutral gas such as N ₂ which does not adversely affect Si or an inert gas such as Ar. After being installed on the substrate fixing base 13 of FIG. 1, the gas is exhausted to a vacuum chamber (for example, about 10 ⁻⁶ Torr or less), and the inner wall of the baking heater wire 15 is heated for a required time (for example, about 80 to 200 ° C.). Then, the water concentration in the atmosphere is reduced and the cleanliness is improved (first preliminary step). The processing chamber 1 is also evacuated to a high vacuum in advance, and the inner wall of the processing chamber 1 is heated by the heating unit 3 (for example, about 700 to 1200 ° C.) to form a clean atmosphere having a low water content (second preliminary step). The residual moisture concentration in the substrate exchange chamber 7 is equal to or lower than the required moisture partial pressure (for example,
(Approx. 10 ⁻⁸ Torr or less), after introducing the above-mentioned neutral gas or inert gas until the pressure becomes the same as the processing atmosphere in the processing chamber 1, the processing chamber opening / closing part 6 is opened.
Is transferred to the processing chamber 1 (first step). Incidentally, the processing room 1
Also, when the same low moisture pressure as the atmosphere of the substrate exchange chamber 7 is reached, the neutral gas or the inert gas is introduced to the required temperature (the moisture concentration at this time is about 100 to 1 pp).
m or less). After the transfer, the processing chamber opening / closing part 6 is closed, and while the appropriate amount of the neutral gas or the inert gas is introduced into the processing chamber 1, at the same time, the processing chamber 1 is evacuated to the required amount of 1
While maintaining the pressure lower than atmospheric pressure (for example, about 750 to 1 Torr), the substrate 14 is heated to a required oxidation / nitriding temperature (for example, about 700 to 1200 ° C.) (second step). At the time when the required oxidation / nitriding temperature is reached, oxygen or nitrogen containing, for example, O ₂ , NH ₃ , N ₂ O, etc. is contained in place of the neutral gas or inert gas introduced into the processing chamber 1. The Si substrate is introduced by introducing gas at a required concentration and flow rate into the processing chamber 1 and simultaneously exhausting the gas to maintain the processing chamber 1 at a pressure lower than the required 1 atm (eg, about 750 to 1 Torr). An ON thin film is formed on the exposed surface by a thermal diffusion reaction (third step). The procedure for forming the ON thin film in the third step is from the beginning to ON.
It may be formed as a film composition, or may be nitrided after oxidation or oxidized after nitridation. When the required film thickness is reached, the introduction of the raw material gas is stopped, the neutral gas or the inert gas is introduced into the processing chamber 1 instead, and the inside of the processing chamber 1 is filled with this gas. Then, the substrate 14 is cooled to a temperature (for example, about 600 ° C. to around room temperature) that does not interfere with the next step (generally, the gate electrode forming step) (fourth step). The cooling is performed in the substrate exchange chamber in which the substrate 14 is in a gas atmosphere equivalent to the atmosphere in the processing chamber 1 when the inside of the processing chamber 1 is replaced with the neutral gas or the inert gas after the film formation. It is possible to obtain the ON thin film for gate in the same low moisture concentration atmosphere by returning to 7 and closing the processing chamber opening / closing part 6 and then cooling to the above temperature.

As described above, by carrying out the method of forming an insulating thin film in a low-moisture-concentration, reduced-pressure gas atmosphere of the present invention, the film-forming rate is too fast in an atmospheric gas atmosphere, and oxidation
Even at a high oxidation / nitriding temperature where the adjustment of the nitriding time is extremely difficult, the supply amount of the raw material gas to the substrate 14 can be arbitrarily controlled in the depressurized gas atmosphere, so that the required oxidation / nitriding temperature can be extremely controlled and reproducible. It was possible to realize an extremely thin (for example, 5 nm or less) ON thin film for gate on the exposed portion of the Si substrate surface of the substrate 14. Moreover, because the treatment is performed under ultra-low moisture, the film quality of the insulating thin film itself, which is important for such ultra-thin films, and the interface characteristics between the insulating thin film and the substrate are improved, which is a cause of deterioration of characteristics over time. The charge accumulation in the film could be reduced or suppressed. The results described here are merely one example of the effectiveness of the present invention, and at the required temperature for carrying out the present invention, and
Since the adverse effect of moisture in the atmosphere can be suppressed almost completely,
A high-quality insulating thin film can be realized with high reliability.

A third example of the method of forming an insulating thin film in a low moisture atmosphere of the present invention will be outlined.

In the substrate exchange chamber 7 in which the substrate 14 having the patterned Si substrate exposed portion is filled with a neutral gas such as N ₂ which does not adversely affect Si or an inert gas such as Ar. After being installed on the substrate fixing base 13 of FIG. 1, the gas is exhausted to a vacuum chamber (for example, about 10 ⁻⁶ Torr or less), and the inner wall of the baking heater wire 15 is heated for a required time (for example, about 80 to 200 ° C.). Then, the water concentration in the atmosphere is reduced and the cleanliness is improved (first preliminary step). The processing chamber 1 is also evacuated to a high vacuum in advance, and the inner wall of the processing chamber 1 is heated by the heating unit 3 (for example, about 700 to 1200 ° C.) to form a clean atmosphere having a low water content (second preliminary step). The residual moisture concentration in the substrate exchange chamber 7 is equal to or lower than the required moisture partial pressure (for example,
(Approx. 10 ⁻⁸ Torr or less), after introducing the above-mentioned neutral gas or inert gas until the pressure becomes the same as the processing atmosphere in the processing chamber 1, the processing chamber opening / closing part 6 is opened.
Is transferred to the processing chamber 1 (first step). Incidentally, the processing room 1
Also, when the same low moisture pressure as the atmosphere of the substrate exchange chamber 7 is reached, the neutral gas or the inert gas is introduced to the required temperature (the moisture concentration at this time is about 100 to 1 pp).
m or less). After the transfer, the processing chamber opening / closing part 6 is closed, and while the appropriate amount of the neutral gas or the inert gas is introduced into the processing chamber 1, the processing chamber 1 is simultaneously evacuated to a required pressure (for example, about 2000-0.1 Tor
The substrate 14 is heated to a required oxidation / nitriding temperature (for example, about 700 to 1200 ° C.) while being kept at r) (second step). At the time of reaching the required oxidation / nitriding temperature, together with the neutral gas or the inert gas introduced into the processing chamber 1, at the same time, for example, O ₂ , NH ₃ , N ₂ O, etc. are formed.
While introducing a gas containing oxygen or nitrogen into the processing chamber 1 at a required flow rate, the gas is simultaneously evacuated in some cases, and the pressure inside the processing chamber 1 is reduced to a required pressure (for example, about 2000 to 0.1 Torr).
r), or a pressure lower than the required 1 atm (eg about 7
50 to 1 Torr)
An ON thin film is formed on the exposed surface of the substrate by a thermal diffusion reaction (third step). As the ON thin film forming procedure in the third step, the ON film composition may be formed from the beginning.
Alternatively, nitridation after oxidization or oxidation after nitridation may be performed. When the required film thickness is reached, the introduction of the raw material gas is stopped, and the processing chamber 1 is filled with the neutral gas or the inert gas which is continuously introduced into the processing chamber 1. 14
Is cooled to a temperature (for example, about 600 ° C. to around room temperature) that does not interfere with the next step (generally, the gate electrode forming step) (fourth step). In addition, this cooling is performed after the film is formed in the processing chamber 1.
When the inside is replaced with the neutral gas or the inert gas, the substrate 14 is returned to the substrate exchange chamber 7 in a gas atmosphere equivalent to the atmosphere in the processing chamber 1, and the processing chamber opening / closing unit 6 is closed. Then, even if cooled to the above temperature, an ON thin film for gate in the same low moisture concentration atmosphere can be obtained.

As described above, by carrying out the method of forming an insulating thin film in a low moisture concentration / diluting gas atmosphere of the present invention, the film forming rate is too fast in a normal pressure source gas atmosphere,
Even at a high oxidation / nitridation temperature where it is extremely difficult to adjust the oxidation / nitridation time, the supply amount of the raw material gas to the substrate 14 can be arbitrarily controlled in the diluting gas atmosphere, so that the required oxidation / nitridation can be performed with excellent controllability and reproducibility. It was possible to realize an extremely thin ON thin film for gate (for example, 5 nm or less) on the exposed portion of the Si substrate surface of the substrate 14 at temperature. Moreover, because the treatment is performed under ultra-low moisture, the film quality of the insulating thin film itself, which is important for such ultra-thin films, and the interface characteristics between the insulating thin film and the substrate are improved, which is a cause of deterioration of characteristics over time. The charge accumulation in the film could be reduced or suppressed. The results described here are only one example of the effectiveness of the present invention, and by implementing the present invention, it is possible to suppress the adverse effect of moisture in the atmosphere at a required temperature almost completely. A thin film can be realized with high reliability.

Although the above-mentioned embodiments are described by taking the formation of the ON thin film for gates as an example, in addition to this, for forming an insulating thin film using molecular beam, plasma, ion beam, photochemical reaction, etc. Needless to say, the present invention can be applied to the formation of insulating thin films for compound semiconductors and heterojunction devices, and various other insulating thin film formations. In addition, even if the substrate is heated by the infrared irradiation heating method, or if the processing chamber has a multi-stage, vertical type device configuration, or in order to perform other substrate processing, the substrate is irradiated with light or the substrate is heated. However, the present invention does not deviate from the gist of the present invention, even if the substrate transfer mechanism or the substrate exchanging chamber moving mechanism is changed.

[0025]

As is apparent from the above-mentioned embodiments, the present invention enables highly reliable formation of an insulating thin film of extremely high quality.

The present invention is very effective for highly reliable formation of high-quality insulating thin films for various semiconductor elements including high-quality gate insulating thin film formation. Therefore, the industrial advantages of implementing the present invention are extremely large.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram showing an embodiment of an insulating thin film forming apparatus according to the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Processing chamber, 2a, 2b ... Moisture removal device, 3 ... Heating part, 4
... Processing chamber gas introduction system, 5 ... Processing chamber exhaust system, 6 ... Processing chamber opening / closing section, 7 ... Substrate exchange chamber, 8 ... Substrate exchange chamber gas introduction system, 9 ... Substrate exchange chamber exhaust system, 10 ... Expansion tube , 11 ... Driving part for transferring substrate, 12 ... Substrate fixing base support part, 13 ... Substrate fixing base, 14 ... Substrate, 15 ... Baking heater wire, 16 ...
Expansion direction.

Claims (5)

[Claims] 1. A method of forming an insulating thin film containing oxygen and nitrogen in an element having a structure having an insulating thin film layer on a semiconductor substrate, the first step of placing the semiconductor substrate in an atmosphere filled with a predetermined gas. A second step of heating the semiconductor substrate to a predetermined temperature by maintaining the atmosphere at a predetermined water concentration of about 100 ppm or less with a predetermined gas, and oxygen or nitrogen as a raw material of the insulating thin film in the atmosphere. With a gas containing, maintaining a predetermined moisture concentration of about 100 ppm or less, a third step of forming the insulating thin film, and after forming the insulating thin film in the third step, the atmosphere is filled with a predetermined gas, A fourth step of cooling the semiconductor substrate to a predetermined temperature lower than the heating temperature of the semiconductor substrate in the atmosphere, the method for forming an insulating thin film. 2. A method of forming an insulating thin film containing oxygen and nitrogen in an element having a structure having an insulating thin film layer on a semiconductor substrate, the first step of placing the semiconductor substrate in an atmosphere filled with a predetermined gas. And a second step of heating the semiconductor substrate to a predetermined temperature while maintaining the atmosphere with a predetermined gas at a predetermined pressure of about 750 Torr or less and maintaining the atmosphere at a predetermined moisture concentration of about 100 ppm or less. And maintaining the atmosphere at a predetermined pressure of about 750 Torr or less with a gas containing oxygen or nitrogen as a raw material of the insulating thin film, and maintaining the atmosphere at a predetermined moisture concentration of about 100 ppm or less. And forming the insulating thin film in the third step, filling the atmosphere with a predetermined gas, and heating the semiconductor substrate in the atmosphere at a temperature higher than the heating temperature of the semiconductor substrate. The fourth step and forming method of the insulating thin film characterized by being constituted by cooling the semiconductor substrate to a lower predetermined temperature. 3. A method of forming an insulating thin film containing oxygen and nitrogen in an element having a structure having an insulating thin film layer on a semiconductor substrate, the first step of placing the semiconductor substrate in an atmosphere filled with a predetermined gas. A second step of heating the semiconductor substrate to a predetermined temperature while maintaining the atmosphere at a predetermined moisture concentration of about 100 ppm or less with a predetermined gas; and oxygen or nitrogen serving as a raw material of the insulating thin film in the atmosphere. A third step of forming the insulating thin film by containing the gas and a neutral gas such as pure nitrogen or an inert gas such as argon at a predetermined moisture concentration of about 100 ppm or less, and the insulating step in the third step. A fourth step of forming a thin film, filling the atmosphere with a predetermined gas, and cooling the semiconductor substrate to a predetermined temperature lower than the heating temperature of the semiconductor substrate in the atmosphere. Method for forming the insulating thin film, characterized in that. 4. A processing unit for forming the insulating thin film, which comprises a gas supply system containing oxygen or nitrogen as a raw material for the insulating thin film formed on a semiconductor substrate, and a predetermined gas in an atmosphere of the processing unit. Atmosphere control means for controlling supply and exhaust of the atmosphere to a predetermined pressure; substrate heating means for heating the semiconductor substrate to a predetermined temperature during and after the formation of the insulating thin film; An insulating thin film forming apparatus, further comprising: a means for exchanging the semiconductor substrate from outside air, the substrate exchanging means for transporting and setting the semiconductor substrate. 5. A supply system of a mixed gas of a gas containing oxygen or nitrogen as a raw material of an insulating thin film formed on a semiconductor substrate and a neutral gas such as pure nitrogen or an inert gas such as argon. Processing means for forming the insulating thin film, atmosphere control means for controlling supply of a predetermined gas to the atmosphere of the processing means, and exhaust of the atmosphere to a predetermined pressure, and at the time of forming the insulating thin film, A substrate heating unit for heating the semiconductor substrate to a predetermined temperature after formation, an atmosphere control unit, and a substrate exchanging unit for transporting and placing the semiconductor substrate in the processing unit, shielding the semiconductor substrate from the outside air. An insulating thin film forming apparatus characterized by: