JPH11297712A - Formation method for compound film and manufacture of semiconductor element - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide the formation method of a compound film for forming a satisfactory compound film, in a short time, while turning a boundary between a semiconductor and the compound film formed on it into a satisfactory state and the manufacturing method of a semiconductor element using it. SOLUTION: This forming method of a compound film is provided with a process for exposing the surfaces of semiconductors 2, 3a, 3b, 4a and 4b to atmospheric gas for forming a compound composed by combining with the constituent elements which constitute the semiconductor and forming a compound thin film 6 on the surfaces of the semiconductors 2, 3a, 3b, 4a and 4b and a process for forming a compound film 7 through a vapor phase formation method on the compound thin film 6.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method for forming a compound film and a method for manufacturing a semiconductor device.

[0002]

2. Description of the Related Art In recent years, silicon carbide semiconductor devices have been actively researched and developed as environment-resistant devices and power devices.

As such a silicon carbide semiconductor device, a field effect semiconductor device (FET), particularly a MOS-FET, has received attention.

The insulating film (gate insulating film) formed between the channel and the gate electrode of the MOS-FET is usually a silicon oxide (SiO _x ) film formed by thermally oxidizing the surface of silicon carbide. Or a silicon oxide film formed by a CVD method (chemical vapor deposition method).

[0005]

However, the gate insulating film needs to have a predetermined thickness or more from the viewpoint of withstand voltage and the like. However, in the method of forming a silicon oxide film by a thermal oxidation method, the thickness of the silicon oxide film is reduced. As the film thickness increases, the turbulence of the silicon carbide surface on the channel, that is, the interface between the silicon carbide surface and the silicon oxide film formed thereon increases.

As a result, there arises a problem that the speed of electrons passing through the channel becomes slow and sufficient element characteristics cannot be obtained.

Further, the thermal oxidation method has a problem that the growth of an oxide film is slow and a long time is required for manufacturing.

In addition, a silicon oxide film is formed on the surface of silicon carbide.
When forming silicon carbide, silicon and silicon carbide
Oxygen supplied to oxidize the element surface
CO _x(X is 0 or more), but the thickness of the silicon oxide film
When the amount increases, the CO_xSpread from the silicon oxide film to the outside
Scattering is not enough. As a result, this CO_xKi
Due to the vicinity of the interface between the silicon carbide surface and the silicon oxide film
A precipitate containing carbon is generated beside the silicon oxide
The growth of the film is hindered and CO2 is contained in the silicon oxide film._x
Problems occur.

Further, an insulating film such as a silicon oxide film formed by a vapor phase growth method such as a CVD method has a disadvantage that when an unsaturated bond (called a dangling bond in the case of a covalent bond crystal) is present on the growth surface, the insulating film is not formed on the growth surface. There is a problem that the interface between the formed insulating films and the characteristics of the insulating film are deteriorated.

The present invention has been made in view of the above-mentioned problems, and forms a good compound film in a short time while keeping an interface between a semiconductor and a compound film formed thereon good. An object is to provide a method for forming a compound film and a method for manufacturing a semiconductor device using the same.

[0011]

According to the method of forming a compound film of the present invention, an atmosphere gas for forming a compound formed by combining with a constituent element of the semiconductor is exposed to a semiconductor surface, and the compound is exposed to the semiconductor surface. A step of forming a thin film; and a step of forming a compound film on the compound thin film by a vapor phase formation method.

In the present invention, an atmosphere gas for forming a compound formed by combining with the constituent elements of the semiconductor is exposed, and the thickness of the compound thin film formed on the semiconductor surface is small. Can be suppressed to a small extent.

Further, since the compound thin film has a small thickness, an undesired gas generated by the reaction between the semiconductor and the atmospheric gas is released to the outside from the thin compound thin film. Generation of undesired precipitates generated near the interface between the compound thin films can be suppressed.

In addition, since the unsaturated bond is terminated by an atmosphere gas for forming a compound formed by combining with the constituent elements of the semiconductor, the presence of the unsaturated bond is reduced. As a result, the interface between the semiconductor and the compound thin film, the interface between the compound thin film and the compound film, and the compound film formed on the compound thin film are improved.

Since the thickness of the compound thin film formed by the formation method having a low growth rate is reduced and the thickness of the compound film formed by the vapor growth method having a high growth rate is increased, The production time of a good compound film having a predetermined thickness can be shortened while improving the interface between the compound film and the compound thin film.

In the method for forming a compound film according to the present invention, a step of exposing a semiconductor surface to an atmosphere gas for terminating an unsaturated bond on the surface to form a compound thin film on the semiconductor surface;
Forming a compound film on the compound thin film by a vapor phase formation method.

According to the present invention, the semiconductor surface is exposed to an atmosphere gas for terminating the unsaturated bond on the surface, and the compound thin film formed on the semiconductor surface has a small thickness. Disturbance can be suppressed to a small extent, and the presence of unsaturated bonds is reduced, so that the compound film formed on the compound thin film is good.

Further, since the compound thin film has a small thickness, an undesired gas generated by the reaction between the semiconductor and the atmospheric gas is released to the outside from the thin compound thin film. And the generation of undesired precipitates generated in the vicinity of the interface between the thin film and the compound thin film.

Since the thickness of the compound thin film formed by the formation method having a low growth rate is reduced and the thickness of the compound film formed by the vapor deposition method having a high growth rate is increased, The production time of a good compound film having a predetermined thickness can be shortened while improving the interface between the compound film and the compound thin film.

The method of forming a compound film according to the present invention comprises the steps of: oxidizing a surface of a semiconductor made of silicon carbide to form a compound thin film made of silicon oxide on the surface of the silicon carbide; Forming a compound film by a vapor phase formation method.

In the present invention, since the compound thin film made of silicon oxide has a small thickness, disturbance at the interface between the silicon carbide surface and the silicon oxide film can be suppressed to a small level.

Furthermore, since the thickness of the silicon oxide film is small, gas, such as CO _x resulting silicon carbide and oxidizing gas reacts, because is emitted to the outside from the thin silicon oxide film of this thickness, Undesired precipitates generated near the interface between the silicon carbide surface and the silicon oxide film can be suppressed.

Moreover, since the unsaturated bond is terminated by the oxidizing gas, the presence of the unsaturated bond is reduced. As a result, the interface between the silicon carbide film and the silicon oxide film, the interface between the silicon oxide film and the compound film, and the compound film formed on the silicon oxide film are improved.

Then, the thickness of the silicon oxide film formed by a formation method having a low growth rate, for example, a thermal oxidation method is reduced,
Since the thickness of the compound film formed by the formation method having a high growth rate is increased, the production of a good compound film having a predetermined film thickness while improving the interface between the silicon carbide and the silicon oxide film is improved. Time can be shortened.

Particularly, the compound film is made of silicon oxide.

Although it is possible to use AlN or the like as the compound film, when the compound film formed on the silicon oxide film is silicon oxide, the same material is used, so that a better compound film can be formed. Is done.

In particular, the thickness of the compound thin film is smaller than the thickness of the compound film.

Further, the surface is characterized by having a step-like shape.

In this case, an off-substrate (inclined substrate: a substrate having a surface inclined from a low index surface) may be used as the substrate.

Further, among the compound thin film and the compound film, at least the compound film is an insulating film. In particular, both the compound thin film and the compound film may be insulating films.

When the compound thin film is an oxide thin film, it is manufactured by using an oxidizing gas (such as oxygen, ozone, NO ₂ or a mixed gas of oxygen and water vapor) or an oxidizing species such as atomic oxygen and oxygen ions. A thermal oxidation method in which annealing is performed in an atmosphere gas such as an active species) is used. In the case of a nitride thin film, a method of annealing in an atmosphere gas of a nitriding gas such as N ₂ or NH ₃ is used for manufacturing the thin film. Used.

The above-mentioned vapor phase growth method includes a CVD method,
A sputtering method, an evaporation method, a reactive evaporation method, an MBE method, or the like can be appropriately used.

Further, the semiconductor surface is flattened,
Preferably, a surface cleaning treatment is performed. The semiconductor surface may be a semiconductor substrate surface or a semiconductor film surface.

A method of manufacturing a semiconductor device using the method of forming a compound film according to the present invention, comprising the steps of: forming the compound thin film on the surface of the semiconductor; Forming the compound film by a method.

In this case, since the compound thin film / compound film becomes favorable, if this is an insulating film, sufficient insulating characteristics can be obtained. In addition, since the interface between the surface of the semiconductor and the compound thin film is good, device characteristics can be improved.

Further, the device can be manufactured in a short time.

Further, the semiconductor device is a field effect type semiconductor device, wherein a step of forming the compound thin film as a gate insulating film on the surface of the semiconductor on a channel, and a step of forming the compound thin film on the compound thin film by a vapor phase forming method. Forming the compound film of the gate insulating film.

In this case, since the interface between the surface of the semiconductor on the channel and the gate insulating film is good, the speed of electrons traveling in the channel is improved. Therefore, the element operates at a sufficient speed.

[0039]

DESCRIPTION OF THE PREFERRED EMBODIMENTS M according to a first embodiment of the present invention
The OS-FET will be described in detail with reference to the drawings. FIG. 1 is a schematic configuration diagram of the MOS-FET of the present embodiment.

In FIG. 1, 1 is an n-type SiC substrate and 2 is an n-type S
The n-type SiC epitaxial films 3a and 3b formed on the iC substrate 1 are p-type impurity implanted regions 4a and 4a formed separately from each other in the n-type SiC epitaxial film 2.
b is an n-type impurity implantation region formed in each of the p-type impurity implantation regions 3a and 3b.

5a is a drift portion formed below the spaced portion of the n-type SiC epitaxial film 2, 5b, 5c
Represents n in the p-type impurity implanted regions 3a and 3b, respectively.
This is a channel portion formed between the mold impurity implantation regions 4a and 4b and the separation.

Reference numeral 6 denotes a portion on the channel portions 5b and 5c, on the n-type SiC epitaxial film 2 on the drift portion 5a, and n
-Type impurity doped region 4a, a portion on the formed silicon oxide (SiO _x) ultrathin oxide insulating film made of 4b, 7 consists of very thin oxide insulating film 6 on which is formed in silicon oxide (SiO _x) It is a deposited oxide insulating film. According to the present invention, the gate insulating film has a two-layer structure of an ultra-thin oxide insulating film 6 and a deposited oxide insulating film 7 having a sufficiently large thickness as compared with this.

Reference numeral 8 denotes a gate electrode made of a polycrystalline Si film formed on the deposited oxide insulating film 7, and 9a is formed on the p-type impurity implantation region 3a and the n-type impurity implantation region 4a apart from the gate electrode 8. A source electrode 9b made of a metal film of Ni or the like, 9b is a source electrode made of Ni or the like formed on the p-type impurity implantation region 3b and the n-type impurity implantation region 4b while being separated from the gate electrode 8, and 10 is an n-type SiC A drain electrode formed on the back surface of the substrate 1 and made of Ni or the like.

A method for manufacturing such an element will be described below with reference to the drawings.

First, as shown in FIG. 2A, a surface-cleaned n-type SiC substrate (Nd-doped: Nd concentration 1 ×
10 ¹⁸ to 1 × 10 ²¹ cm ⁻³ ) 1 is prepared.

As the cleaning treatment, an n-type SiC substrate 1
After washing the main surface with acetone and ethanol with an organic solvent, annealing the main surface in an oxygen atmosphere at 1150 ° C. for 80 to 800 minutes to form a silicon oxide film on the surface,
The silicon oxide film is removed by etching with a 1 to 5% HF aqueous solution, and then a buffered HF solution treatment is performed as a hydrogen termination treatment.
A low dissolved oxygen pure water treatment, a boiling pure water treatment, or an annealing treatment at 700 to 1200 ° C. in a hydrogen atmosphere is performed.

In this embodiment, 4H-SiC or 6H-SiC is used as the n-type SiC substrate 1, and the principal surface is defined as (11) from (0001) plane or (000-1) plane.
A surface inclined from 1 degree to 10 degrees in the [-20] direction was used.

Next, as shown in FIG.
An n layer having a thickness of 1 to 50 μm is formed on the main surface of the C substrate 1 by the CVD method.
Type SiC epitaxial film (Nd-doped: Nd concentration 1 ×
10 ^Fifteen~ 1 × 10¹⁷cm^-32) is formed.

Subsequently, as shown in FIG.
a p-type impurity implanted region 3a in the iC epitaxial layer 2;
3b is formed by ion implantation. Here, the implantation impurity is Al, Ga or B, and the implantation temperature is 500 to 1000.
C., the injection amount is 1 × 10 ¹⁵ to 1 × 10 ¹⁸ cm ⁻³ .

Next, as shown in FIG. 2D, n-type impurity implanted regions 4a and 4b are formed in the p-type impurity implanted regions 3a and 3b by ion implantation. Here, the implantation impurity is N or P, the implantation temperature is 500 to 1000 ° C.,
The injection amount is 1 × 10 ¹⁸ to 1 × 10 ²¹ cm ⁻³ .

After the above steps, the p-type impurity implanted regions 3a, 3a
In order to activate the impurities implanted in the b and n-type impurity implanted regions 4a and 4b so as to function as carriers, annealing is performed at 800 to 1500 ° C. in a vacuum or in an inert gas atmosphere.

Next, as shown in FIG. 2E, p-type impurity implanted regions 3a and 3b, n-type impurity implanted regions 4a and 4b
After the surface of the n-type SiC epitaxial layer 2 is subjected to the same treatment as the surface cleaning treatment, the surface is
A thick ultra-thin oxide insulating film 6 was formed by a thermal oxidation method.

As the thermal oxidation method, 1 to 760 Torr
A method of performing heat treatment at 600 to 1200 ° C. in an oxygen atmosphere of r was used. This heat treatment may be performed by irradiating the main surface of the substrate with ultraviolet rays.

The atmosphere gas may be an ozone or NO ₂ atmosphere instead of oxygen. In this case, the atmosphere gas pressure may be 1 × 10 ^{−6 to} 10 Torr, and the heat treatment temperature may be 300 to 1000 ° C.

Further, as a thermal oxidation method, atomic oxygen obtained by plasma treatment of oxygen is supplied at a flow rate of 1 × 10 ¹⁰ to 1 × 10 ²⁰ /.
Irradiation may be performed under the conditions of scm ² and 100 to 1000 ° C.

Thereafter, as shown in FIG. 3A, a sputtering method, a vapor deposition method or a CV
A deposited oxide insulating film 7 having a thickness of 20 to 500 nm is formed by a vapor deposition method such as the D method.

Next, as shown in FIG. 3B, the ultra-thin oxide insulating film is left so as to leave the channel portions 5b and 5c, the drift portion 5a, and a part of the n-type impurity implanted regions 4a and 4b. 6 and the deposited oxide insulating film 7 are removed by etching to remove the p-type impurity implanted regions 3a and 3b and the n-type impurity implanted regions 4a and 4a.
Expose b.

Subsequently, as shown in FIG. 3C, the p-type impurity-implanted regions 3a, 3b and the n-type impurity are exposed on the ultra-thin oxide insulating film 6 and the deposited oxide insulating film 7 patterned by the etching. 2 on injection regions 4a and 4b
A polycrystalline Si film 18 having a thickness of 00 nm to 2 μm is formed by a CVD method or a sputtering method.

Thereafter, as shown in FIG. 4A, the polycrystalline Si is formed so as to exist only on the deposited oxide insulating film 7.
The gate electrode 8 is formed by patterning the film 18.

Next, as shown in FIG. 4B, Ni is deposited on the gate electrode 8, the exposed p-type impurity implanted regions 3a and 3b and the n-type impurity implanted regions 4a and 4b and the exposed deposited oxide insulating film 7. While forming a metal film 19 made of
A drain electrode 10 made of Ni or the like is formed on the back surface of the mold SiC substrate 1.

Thereafter, as shown in FIG. 4C, the metal film 19 on and around the deposited oxide insulating film 7 is removed by etching to form source electrodes 9a and 9b.
Laser annealing is performed so that the source electrodes 9a and 9b and the drain electrode 10 are in ohmic contact with each other to complete the process.

In the manufacturing method of this embodiment, since the thin oxide insulating film 6 (compound thin film) has a small thickness, the channel portions 5b, 5
Disturbance at the interface between the surfaces of the p-type impurity implanted regions 3a and 3b on c and the thin oxide insulating film 6 can be reduced.

Further, since the thin oxide insulating film 6 has a small thickness, undesired CO _x generated by the reaction between SiC and oxygen constituting the atmospheric gas is easily released from the thin oxide insulating film 6 to the outside. Therefore, it is possible to suppress the generation of undesired precipitates near the interface such as between the surfaces of the p-type impurity implanted regions 3a and 3b and the thin oxide insulating film 6, and to prevent CO _{x from} being mixed into the thin oxide insulating film 6. Can be reduced.

Further, since the unsaturated bond (terminated Si) on the surface is terminated by oxygen of the atmospheric gas, the existence of the unsaturated bond is reduced. As a result, the interface between the thin oxide insulating film 6 and the base, the thin oxide insulating film 6 and the deposited oxide insulating film 7
And the deposited oxide insulating film 7 formed on the thin oxide insulating film 6 is excellent.

The thickness of the thin oxide insulating film 6 formed by the formation method with low growth rate (thermal oxidation method) is small, and the deposited oxide insulation film formed by the formation method with high growth rate (vapor phase growth method). Since the thickness of the film 7 is increased, it is possible to shorten the manufacturing time of a favorable gate insulating film while obtaining characteristics such as insulation resistance characteristics.

Therefore, a MOS-FET with good operating characteristics
Can be obtained in a short production time.

The MOS-F according to the second embodiment of the present invention
The ET will be described in detail with reference to the drawings. FIG. 5 is a schematic configuration diagram of the MOS-FET of the present embodiment.

In FIG. 5, 31 is an n-type SiC substrate, and 32 is an n-type SiC substrate.
N-type SiC epitaxial film formed on n-type SiC substrate 1, 33 is a p-type SiC epitaxial film formed on n-type SiC epitaxial film 32, 34 is p-type SiC
This is a U-shaped gate electrode groove that penetrates through the epitaxial film 33 and reaches the n-type SiC epitaxial film 32.

Numerals 35 a and 35 b are n-type impurity implanted regions formed in the p-type SiC epitaxial film 33 and formed in close contact with the U-shaped gate electrode trench 34.

Reference numerals 36a and 36b denote channel portions formed in the p-type SiC epitaxial film 33 in close contact with the electrode grooves 34 and between the n-type impurity implanted regions 35a and 35b and the n-type SiC epitaxial film 32. And 37b are drift portions formed between the channel portions 36a and 36b and the substrate 31.

Reference numeral 38 denotes a groove on the U-shaped gate electrode groove 34 and n
Ultra-thin oxide insulating film made of silicon oxide (SiO _x ) formed over a part of the type impurity implantation regions 35a and 35b;
Reference numeral 39 denotes a deposited oxide insulating film made of silicon oxide (SiO _x ) formed on the ultra-thin oxide insulating film 38. In the present invention, the gate insulating film has a two-layer structure of an ultra-thin oxide insulating film 38 and a deposited oxide insulating film 39 having a sufficiently large thickness as compared with this.

Reference numeral 40 denotes a gate electrode made of a polycrystalline Si film formed on the deposited oxide insulating film 39. Reference numeral 41a denotes an n-type impurity implanted region 35a separated from the gate electrode 40 and a p-type S
A source electrode 41b made of a metal film of Ni or the like formed over a part of the iC epitaxial film 33 is separated from the gate electrode 40 by a distance above the n-type impurity implantation region 35 and the p-type S
a source electrode 42 made of Ni or the like formed over a part of the iC epitaxial film 33;
Is a drain electrode formed of Ni or the like formed on the back surface of the substrate.

A method for manufacturing such an element will be described below with reference to FIG.

First, as shown in FIG. 6 (a), an n-type SiC substrate (N
d-doping: Nd concentration 1 × 10 ^{18 -1} × 10 ²¹ cm ⁻³ ) 3
Prepare 1

Next, a CV is placed on the main surface of the n-type SiC substrate 31.
An N-type SiC epitaxial film (Nd doped: Nd concentration: 1 × 10 ¹⁵ to 1 × 10 ¹⁷ cm) having a thickness of 1 to 50 μm by the D method
^-3 ) After forming 32, n-type SiC epitaxial film 3
P-type SiC epitaxial film (N
d-doping: Nd concentration 1 × 10 ¹⁵ to 1 × 10 ¹⁸ cm ⁻³ ) 3
Form 3

Thereafter, the p-type SiC epitaxial layer 33
An n-type impurity implantation region 35 is formed therein by ion implantation, and annealing is performed at 800 to 1500 ° C. in a vacuum or an inert gas atmosphere in order to activate the implanted impurity to function as a carrier. Here, the implantation impurity is N or P, the implantation temperature is 500 to 1000 ° C., and the implantation amount is 1 × 10 ¹⁸ to 1 × 10 ²¹ cm ⁻³ .

Next, as shown in FIG. 6B, an n-type impurity implanted region 35 is formed by reactive ion etching (RIE) using CF ₄ and O ₂ , or CF ₄ and H ₂ gas. Then, a U-shaped gate electrode groove 34 that penetrates the p-type SiC epitaxial film 33 immediately below and reaches the n-type SiC epitaxial film 32 is formed.

Subsequently, as shown in FIG. 5, the inner wall of the U-shaped gate electrode groove 34, the n-type impurity implanted regions 35a, 35a
After performing the same surface cleaning treatment as that of the first embodiment on the surface of the p-type SiC epitaxial layer 33, 0.5 to 5 n
An ultrathin oxide insulating film 38 having a thickness of m is formed by the same thermal oxidation method as that of the first embodiment, and subsequently, a vapor deposition method such as a sputtering method, a vapor deposition method or a CVD method is formed on the ultrathin oxide insulating film 38 A deposited oxide insulating film 39 having a thickness of 20 to 500 nm is formed. Thereafter, the ultra-thin oxide insulating film 38 and the deposited oxide insulating film 39 are removed by etching so as to leave the U-shaped gate electrode groove 34 and a part of the n-type impurity implanted regions 35a and 35b. 35a, a part of 35b and p
The type SiC epitaxial film 33 is exposed.

Subsequently, a gate electrode 4 made of a polycrystalline Si film formed by a CVD method or a sputtering method with a thickness of 200 nm to 2 μm on the ultra-thin oxide insulating film 38 and the deposited oxide insulating film 39 patterned by the etching.
0, exposed n-type impurity implanted regions 35a, 35b and p
Forming metal films 41a and 41b made of Ni or the like formed on the SiC epitaxial layer 33 by vapor deposition or the like, and forming a drain electrode 42 of Ni or the like on the back surface of the n-type SiC substrate 31 by vapor deposition or the like I do.

This embodiment also provides the same effects as those of the first embodiment.

In the above embodiment, a silicon oxide film is formed as a compound film (deposited oxide insulating film). However, an AlN film or the like may be used.

Further, a configuration may be adopted in which the above-described conductivity type is reversed conductivity type.

In the above description, an example of the gate insulating film has been described, but the present invention can be applied to other cases such as a passivation film.

Further, the present invention can be applied to a case where a compound film is formed by a vapor phase growth method after forming a compound thin film on a semiconductor other than SiC.

[0085]

According to the present invention, it is possible to provide a compound film forming method for forming a good compound film in a short time while keeping the interface between the semiconductor and the compound film formed thereon in a good state. Further, it is possible to provide a method for manufacturing a semiconductor device having excellent device characteristics and a short manufacturing time using this method.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of a semiconductor device according to a first embodiment of the present invention.

FIG. 2 is a view illustrating a method of manufacturing the semiconductor device according to the first embodiment.

FIG. 3 is a diagram showing a method for manufacturing the semiconductor device according to the first embodiment.

FIG. 4 is a diagram showing a method for manufacturing the semiconductor device according to the first embodiment.

FIG. 5 is a schematic configuration diagram of a semiconductor device according to a second embodiment of the present invention.

FIG. 6 is a view illustrating a method for manufacturing a semiconductor device according to the second embodiment.

[Explanation of symbols]

 Reference Signs List 1 n-type SiC substrate 2 n-type SiC epitaxy layer 3 a, 3 b p-type impurity implantation region 4 a, 4 b n-type impurity implantation region 5 b, 5 c channel portion 6 ultra-thin oxide insulating film (compound thin film) 7 deposited insulating film (compound film) Reference Signs List 31 n-type SiC substrate 32 n-type SiC epitaxy layer 33 p-type SiC epitaxy layer 35 a, 35 b n-type impurity implantation region 36 b, 36 c channel portion 39 ultra-thin oxide insulating film (compound thin film) 40 deposited insulating film (compound film)

Claims (9)

[Claims] A step of exposing an atmosphere gas for forming a compound formed by combining with a constituent element of the semiconductor to a semiconductor surface to form a compound thin film on the semiconductor surface; Forming a compound film by a forming method. 2. A step of exposing a semiconductor surface to an atmosphere gas for terminating unsaturated bonds on the surface to form a compound thin film on the semiconductor surface, and forming a compound film on the compound thin film by a vapor phase formation method. A method of forming a compound film. 3. A step of oxidizing the surface of a semiconductor made of silicon carbide to form a compound thin film made of silicon oxide on the surface of the silicon carbide; Forming a compound film. 4. The method according to claim 3, wherein the compound film is made of silicon oxide. 5. The method according to claim 1, wherein the thickness of the compound thin film is smaller than the thickness of the compound film. 6. The method according to claim 1, wherein the surface has a step-like shape. 7. The compound thin film and the compound film,
7. The method for forming a compound film according to any one of 1 to 6, wherein at least the compound film is an insulating film. 8. A method of manufacturing a semiconductor device using the method of forming a compound film according to claim 1, wherein the compound thin film is formed on a surface of the semiconductor. A method for manufacturing a semiconductor device, comprising: a step of forming the compound film on the compound thin film by a vapor phase formation method. 9. The semiconductor device according to claim 1, wherein the semiconductor device is a field-effect semiconductor device, wherein the compound thin film as a gate insulating film is formed on a surface of the semiconductor on a channel, and the compound thin film is formed on the compound thin film by a vapor phase forming method. 9. The method according to claim 8, further comprising: forming the compound film as a gate insulating film.