JPH08162614A - Mis capacitor and its manufacture - Google Patents

Abstract

PURPOSE: To obtain excellent MOS characteristics wherein hysteresis is not generated in C-V characteristics, by forming a second oxide thin film as an epitaxial film whose main component is oxide of rare earth metal of one kind out of Ce, Pr, Nd, Gd, Tb, Dy, Ho and Er, on a first oxide thin film of specific composition. CONSTITUTION: A first oxide thin film as an epitaxial film whose main component is oxide is formed on an Si single-crystal semiconductor substrate. The composition of the oxide is Zr1-x Rx O2-δ where R is rare earth metal containing Y and x=0-0.75. A second oxide thin film as an epitaxial film whose main component is oxide of one kind of rare earth metal selected out of Ce, Pr, Nd, Gd, Tb, Dy, Ho and Er is formed on the first oxide thin film. Thereby excellent MOS characteristics can be obtained without generating hysteresis in C-V characteristics.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a MIS (Metal-Insulator-Semiconductor) capacitor formed by forming an oxide epitaxial thin film and an electrode film on a Si single crystal wafer.
The present invention relates to a MIS capacitor used as a gate in an FET.

[0002]

2. Description of the Related Art An electronic device has been devised in which a dielectric film is formed and integrated on a Si substrate which is a semiconductor crystal substrate. For semiconductors and dielectrics, LSI with higher integration,
Dielectric isolation LSI by SOI technology, non-volatile memory, infrared sensor, optical modulator and optical switch, OE
IC (Opto-electronic integrate circuit)
dcircuits) etc. have been prototyped.

In a semiconductor device using these dielectric materials, it is necessary to use a single crystal in order to secure optimum device characteristics and its reproducibility. In a polycrystalline body, it is difficult to obtain good device characteristics due to the disturbance of physical quantity due to grain boundaries. This also applies to the thin film material, and an epitaxial film of a functional material as close to a single crystal as possible is desired. If epitaxial formation of oxide dielectrics and ferroelectrics can be realized on a Si substrate, the semiconductor properties of Si and the properties of dielectrics can be positively utilized, so that wide application as described above is possible. Is coming.

S, which is the basis of the capacitor for DRAM,
For the gate of the iFET, a polycrystalline or amorphous SiO ₂ film is usually used as an oxide film to form a MOS structure. With the progress of integration, the size of the MOS capacitor is required to be smaller, and the current degree of integration has reached the limit. SiO _{2 has} a dielectric constant of about 3 and F
In order to secure the charge for operating the ET gate by the MOS capacitor, it is necessary to use a dielectric having a larger dielectric constant instead of SiO ₂ and obtain good MOS characteristics. Since SiO ₂ has a very good compatibility with Si, it has been used for Si devices in a polycrystalline or amorphous state. However, under the present circumstances, other materials in place of SiO ₂ are not actually used in Si devices in the polycrystalline or amorphous state for the above-mentioned reason.

That is, instead of SiO ₂ , a material having a large dielectric constant, a single crystal, and an excellent MOS (MIS) characteristic is required.

In recent years, the oxide material YSZ (ZrO ₂
It has been reported that materials doped with Si) can be epitaxially grown on Si single crystals. YSZ is a favorable material for MIS capacitors because of its high chemical stability, wide bandgap (about 5 eV), and large dielectric constant (about 20).

A MIS structure was produced and evaluated using this YSZ, and Appl. Phys. Lett. 61 (2
6), 28th December 1992, 318.
Reported on page 4. In this report, MOS (MI
As the S) characteristic, the most basic CV characteristic is evaluated, but a large hysteresis was observed in the CV characteristic, and a good MOS (MIS) characteristic was not obtained.

[0008]

As described above,
The epitaxial YSZ film formed on the Si single crystal is S
Although it is promising as a dielectric film for Si that replaces iO ₂ ,
As the MOS (MIS) characteristics, the most basic C-
Hysteresis is seen in V characteristics, and good MOS (M
The IS) characteristic was not obtained, and it could not be used as a MIS capacitor for Si devices. Therefore, the present invention provides a C / MIS capacitor of electrode / dielectric / Si.
It is an object of the present invention to provide a MIS capacitor for Si devices that exhibits good MIS characteristics without showing hysteresis in the -V characteristic and a method for manufacturing the same.

[0009]

This and other objects are achieved by the present invention which is defined below as (1) to (12). (1) Si single crystal semiconductor substrate and composition Zr _1-x R _x O ₂ -δ formed on the semiconductor substrate (where R is a rare earth metal containing Y and 0 ≦ x <1) ) Is an epitaxial film containing an oxide as a main component, and a first oxide thin film in which x in the composition formula is 0 to 0.75 in at least a substrate adjacent layer portion adjacent to the semiconductor substrate; Ce, Pr, Nd, G formed on one oxide thin film
and a second oxide thin film, which is an epitaxial film containing, as a main component, an oxide of at least one rare earth metal selected from d, Tb, Dy, Ho, and Er. (2) The MIS according to (1), wherein the rare earth metal of the first oxide thin film and the rare earth metal of the second oxide thin film are the same.
Capacitors. (3) The first oxide thin film has a residual layer portion other than the substrate adjacent layer portion, and in this residual layer portion, the Zr content is the Zr content of the substrate adjacent layer portion and the second oxide thin film. The MIS capacitor according to the above (2), which is set between the Zr contents of. (4) The remaining layer portion of the first oxide thin film is a gradient composition thin film in which the Zr content is gradually reduced between the Zr content of the substrate adjacent layer portion and the Zr content of the second oxide thin film. The MIS capacitor according to (3) above. (5) In the method of manufacturing the MIS capacitor according to any one of (1) to (4), the inside of the vacuum chamber is initially set at 1 × 1.
A vacuum of 0 ^-5 Torr or less is applied, and in this state, the Si single crystal substrate is heated to a predetermined temperature, and then Zr and at least 1
At least Zr among the respective metal elements of the species rare earth metal (including Y) is simultaneously evaporated from separate evaporation sources while controlling the ratio of Zr and the rare earth metal to supply the metal to the substrate surface of the single crystal substrate, Simultaneously with or after a lapse of a predetermined time from the supply of the metal, an oxidizing gas is introduced into the vacuum chamber so that the atmosphere in the vacuum chamber at least in the vicinity of the single crystal substrate is 1 × 10 ⁻⁴ to.
1 × 10 ⁻² Torr, and at least after the introduction of the oxidizing gas, they are evaporated at the same time while controlling the ratio of Zr and the rare earth metal, and the first oxide thin film or the first oxide is formed on the substrate surface of the single crystal substrate. A thin film of a material and a thin film of a gradient composition are formed by epitaxial growth, and then the evaporation of Zr is stopped and only the rare earth metal is evaporated while maintaining the introduction of the oxidizing gas.
A method of manufacturing a MIS capacitor, comprising forming a second oxide thin film by epitaxial growth on the first oxide thin film or the graded composition thin film. (6) The MIS according to the above (5), in which an oxidizing gas is injected from the vicinity of the surface of the single crystal substrate to create an atmosphere in which the oxidizing gas partial pressure is higher than other portions only in the vicinity of the single crystal substrate.
Method of manufacturing capacitor. (7) The single crystal substrate has a substrate surface area of 10 cm ² or more, and is rotated in a plane of the substrate to provide the oxidizing gas high partial pressure atmosphere over the entire single crystal substrate. The method for manufacturing a MIS capacitor according to (6) above, which forms a substantially uniform oxide thin film over the entire surface of the single crystal substrate. (8) As the single crystal substrate, a Si single crystal is
The method for manufacturing a MIS capacitor according to any one of the above (5) to (7), wherein the (00) plane is used as the substrate surface. (9) As the single crystal substrate, a substrate having a Si oxide protective film formed on a Si single crystal is used (5) to (8) above.
1. A method for manufacturing a MIS capacitor according to any one of 1. (10) The method for manufacturing a MIS capacitor according to any one of (5) to (9), wherein the single crystal substrate is heated to 750 ° C. or higher. (11) The predetermined time from the supply by evaporation of the metal to the introduction of the oxidizing gas is a time corresponding to 5 nm or less in terms of the film thickness of the metal thin film formed on the single crystal substrate. A method for manufacturing a MIS capacitor according to any one of (1) to (10). (12) When forming the first oxide thin film, first, the ratio of Zr to the rare earth metal is set to a predetermined value and simultaneously evaporated,
A uniform composition layer having a predetermined thickness, in which the ratio of Zr and the rare earth metal is a predetermined value, is formed, and thereafter, the evaporation amount of Zr is gradually reduced to
The method for manufacturing a MIS capacitor according to any one of (5) to (11) above, wherein a graded composition layer in which the content of r is gradually reduced is formed.

[0010]

The MIS capacitor of the present invention is
i single crystal substrate, composition Zr _1-x R _x O ₂ -δ formed on the Si single crystal substrate (where R is a rare earth metal containing Y, preferably x = 0 to 0.75, More preferably, x = 0.20 to 0.50), a first oxide thin film including a layer of an epitaxial film, and Ce, Pr, Nd, Gd, Tb formed on the first oxide thin film, Dy,
When a MOS (MIS) device is constructed with a structure including a second oxide thin film which is an epitaxial film of an oxide of at least one rare earth metal selected from Ho and Er, the most basic CV Good MOS (MI
S) characteristics can be obtained.

Further, in particular, when the single crystal substrate is rotated in its plane, a uniform and high quality oxide thin film can be obtained in a large area of 10 cm ² or more. On the other hand, conventionally, when forming an oxide thin film on a single crystal substrate, the maximum substrate area is 2.25 cm ² (about 15 × 15 mm ² ).

[0012]

A MIS capacitor of the present invention comprises a Si single crystal semiconductor substrate, a first oxide thin film formed on this semiconductor substrate, and a second oxide thin film formed on this first oxide thin film.
It has an oxide thin film.

The first oxide thin film has the composition Zr _1-x R _x
O _{2 −} δ (where R is a rare earth metal containing Y, and 0 ≦
x <1) is an epitaxial film containing an oxide as a main component, and x in the composition formula is 0 to 0.7 in at least a substrate adjacent layer portion adjacent to the semiconductor substrate.
5, preferably 0.2 to 0.50. Hereinafter, in the present specification, this epitaxial film is represented by a case where R is Pr and is represented by PSZ (praseodymium stabilized zircon).
ia). In the first oxide thin film, the composition of the portion other than the substrate adjacent layer portion, that is, the remaining layer portion has a value of x of less than 1 in the above composition formula,
It is desirable to be larger than the value of x in the substrate adjacent layer portion. That is, the first oxide thin film may have a uniform composition as a whole, or may have a composition of Z in the range satisfying the above conditions.
The composition ratio of r and R may change in the film thickness direction.

In the first oxide thin film, the crystallinity of the epitaxial film is at least x in the layer adjacent to the substrate.
Zr in a small region where x is less than 0.2 depending on the range of
_1-x R _x O _2- δ becomes a tetragonal crystal. Above that,
It becomes cubic. Since cubic crystals are more regularly arranged than tetragonal crystals, cubic crystals have higher crystal opposition than tetragonal crystals and are excellent in crystallinity. Since the crystallinity of the second oxide thin film formed on this first oxide thin film is affected by the crystallinity of the first oxide thin film, the value of x in the first oxide thin film is as described above. Is preferably a cubic region of 0.2 or more.

On the other hand, in the region where x exceeds 0.75, although it is a cubic crystal, planes other than the intended crystal plane are mixed. For example, if an attempt is made to obtain a (100) epitaxial film of Zr _1-x R _x O ₂ -δ, in the region where x exceeds 0.75, (11
The crystals of 1) are mixed.

That is, from the range where tetragonal and cubic crystals can be formed and the range where a target crystal plane can be obtained, Zr _1-x R
_{In x} O _{2 −} δ, x is 0 to 0.75, preferably 0.2
A highly crystalline epitaxial film excellent in lattice symmetry can be obtained in the range of up to 0.5.

Zirconium oxide containing no oxygen deficiency is represented by the chemical formula ZrO ₂ , but zirconium oxide containing a rare earth element containing Y changes in the amount of oxygen depending on the type, amount and valence of the added metal element. Therefore, the composition of the oxide thin film of the present invention is represented by the chemical formulas Zr _1-x R _x O _2- δ and δ. δ is usually about 0 to 0.5.

The thickness of the first oxide thin film is 0.5 to 50 n.
m, especially about 1 to 30 nm is preferable. As mentioned above, the first oxide thin film is necessary for epitaxially growing the second oxide thin film at (100). Without the first oxide thin film, the second oxide thin film has a strong (111) orientation, and a (100) epitaxial film cannot be obtained. Therefore, the film thickness of the first oxide thin film is preferably used within the range of excellent crystallinity and surface property. If the thickness of the first oxide thin film is less than 0.5 nm, the surface of the Si substrate cannot be completely covered with the first oxide thin film, and the crystallinity of the oxide of the second oxide thin film deteriorates. . Therefore, it is preferably 0.5 nm or more, and particularly preferably 1 nm or more. Further, if the film thickness is too thick, the irregularities on the surface of the first oxide thin film tend to become large, and if the irregularities of the first oxide thin film are severe, the crystallinity of the oxide of the second oxide thin film deteriorates. . Although it depends on the film forming method, when the film thickness of the first oxide thin film exceeds 50 nm, irregularities of 3 nm or more are likely to appear. Therefore, the thickness of the first oxide thin film is preferably 50 nm or less, particularly 30 nm or less.

The film composition of the first oxide thin film may be uniform. Further, the composition of Zr and R may be changed in the film thickness direction. In this case, x = 0 to 0.75
The remaining layer portion other than the substrate adjacent layer portion is
It is preferable that the Zr content is set between the Zr content of the substrate adjacent layer portion and the Zr content of the second oxide thin film.
At this time, it is preferable that the types of rare earth metals used are the same. The remaining layer portion is preferably a gradient composition thin film in which the Zr content gradually decreases between the Zr content of the substrate adjacent layer portion and the Zr content of the second oxide thin film. Moreover, you may comprise by several layers from which R content differs.
That is, the composition of the balance layer is Zr _1-x R _x O _2-
δ (where R is a rare earth metal containing Y, and x = 0 to
It is less than 1). Due to the existence of this remaining layer portion,
The composition from the first oxide thin film to the second oxide thin film gradually changes, and the misfit of the lattice between the first oxide thin film and the second oxide thin film is small or does not exist,
A highly crystalline epitaxial film can be obtained. In this sense, the balance layer portion is a composition gradient film, and the Zr content is
From the Zr content of the layer adjacent to the substrate to the Zr of the second oxide thin film
Those that gradually decrease to the content of zero are particularly preferable. The layer thickness of the remaining layer portion is preferably about 1 to 49.5 nm. When the remaining layer portion is formed as described above, the substrate adjacent layer portion has a thickness of 0.5 to 49 nm.
It is preferable that the total layer thickness of the substrate adjacent layer portion and the remaining layer portion is about 1.5 to 50 nm.
Furthermore, the first oxide film may have a graded composition in which x gradually increases within a range where the substrate adjacent layer portion satisfies the above composition condition. In this case, the entire first oxide thin film has the composition Zr _1-x R _x O ₂ -δ (where R is a rare earth metal containing Y and x = 0 to 0.75). , _X
May have a gradient composition that gradually and continuously increases. That is, the substrate adjacent layer portion and the remaining layer portion may be naturally integrated to form the first oxide thin film.

The second oxide thin film is made of Ce, Pr, Nd, G
It is an epitaxial film containing, as a main component, an oxide of at least one rare earth metal selected from d, Tb, Dy, Ho and Er. In addition, Ce, Pr, Nd, G
When two or more rare earth metals are used among d, Tb, Dy, Ho and Er, the composition ratio is arbitrary. C
Although e, Pr, Nd, Gd, Tb, Dy, Ho and Er are all rare earth metals, among rare earth metals, Y,
La, Sm, Eu, Yb and the like are not used as main components.
The reason is that Y, La, Sm, Eu, and Yb are the first
Does not grow epitaxially on the oxide thin film layer or MIS
This is because when a capacitor is used, a large hysteresis may occur in the C-V characteristic. In addition, Y, La, Sm,
Eu and Yb may be contained in the rare earth metal as long as they are 20 mol% or less. In addition, an additive may be introduced into the first oxide thin film and the second oxide thin film in order to improve the characteristics thereof. For example, when the first oxide thin film and the second oxide thin film are doped with an alkaline earth such as Ca or Mg, pinholes in the film can be reduced and leakage of the MIS capacitor can be suppressed. Also, Al
And Si has the effect of improving the resistivity of the film. Furthermore, transition metals such as Mn, Fe, Co, and Ni are the first
A level (trap level) due to impurities can be formed in the materials of the oxide thin film and the second oxide thin film, and the conductivity can be controlled by utilizing this level.

The thickness of the second oxide thin film is 0.5 to 50 n.
m, preferably about 1 to 30 nm. The reason is that when the thickness of the second oxide thin film is less than 0.5 nm, the surface of the first oxide thin film is not completely covered with the second oxide, and the first and second oxides are stacked. The effect of the present invention due to is not recognized. That is, when the MIS element is used,
Good C-V characteristics cannot be obtained. Therefore, it is preferably 0.5 nm or more, and particularly preferably 1 nm or more. On the other hand, if the film thickness is too large, the total film thickness of the first and second oxide thin films becomes large, resulting in a decrease in MIS capacity. The total thickness of the first oxide thin film and the second oxide thin film is preferably about 5 to 100 nm. If the total film thickness is less than 5 nm, leakage tends to occur when the MIS capacitor is constructed. It is considered that this is because the possibility that pinholes are generated in the film increases. On the other hand, when the film thickness is 100 nm or more, the capacitance of the MIS capacitor is reduced. As described above, the thickness of the second oxide is 0.5 to 50 nm, preferably 1 to 30 nm in consideration of the thickness of the first oxide.
The degree is good.

Reflection high energy electron diffraction of the second oxide thin film of the MIS capacitor of the present invention.
ctron Diffraction-Hereinafter, it may be referred to as RHEED) The image has a high streak property. That is, RH
The EED image is streak and sharp. As described above, the second oxide thin film of the present invention becomes a single crystal, and when it is used for the insulating layer of the MIS capacitor, the physical quantity is not disturbed by grain boundaries and the good function is exhibited.

In the MIS capacitor of the present invention, the substrate surface of the Si single crystal substrate, that is, the thin film forming surface side is shallowly oxidized (for example, about 5 nm or less) and is oxidized to SiO ₂
And other layers may be formed. This is because oxygen of the oxide of the first oxide thin film may diffuse to the substrate surface of the Si single crystal substrate depending on the type of rare earth metal used for the first oxide thin film. Also, depending on the film formation method, the Si oxide layer may remain on the surface of the Si substrate during the formation of the first oxide thin film.

Next, the method for manufacturing the MIS capacitor of the present invention will be described in detail.

When carrying out the manufacturing method of the present invention, it is desirable to use the vapor deposition apparatus 1 as shown in FIG.

The vapor deposition apparatus 1 has a vacuum chamber 1a, in which a holder 3 for holding a single crystal substrate 2 is arranged. The holder 3 is connected to a motor 5 via a rotary shaft 4, and is rotated by the motor 5 so that the single crystal substrate 2 can be rotated within the substrate surface. In the holder 3,
A heater 6 for heating the single crystal substrate 2 is built in.

The vapor deposition apparatus 1 also includes an oxidizing gas supply device 7, and the oxidizing gas supply port 8 of the oxidizing gas supply device 7 is arranged immediately below the holder 3. As a result, the partial pressure of the oxidizing gas is increased near the single crystal substrate 2. Further below the holder 3, there are a Zr evaporation section 9 and a rare earth metal evaporation section 10.
Is arranged. In addition to the respective metal sources, an energy supply device for supplying energy for vaporization to a metal source such as an electron beam generator is arranged in the Zr vaporization part 9 and the rare earth metal vaporization part 10. . In the figure, P is a vacuum pump.

In the method for manufacturing a substrate for an electronic device of the present invention, first, the single crystal substrate is set in the holder. At this time, a Si single crystal substrate is used as the single crystal substrate, and the (100) plane is selected as the substrate surface on which the target oxide thin film is formed. This is because the functional film formed on the substrate surface is a single crystal epitaxially grown, and the crystal has an appropriate orientation. It is preferable that the surface of the substrate is cleaned by etching using a mirror-finished wafer. Etching cleaning is performed with a 40% ammonium fluoride aqueous solution or the like. M of the present invention
The Si single crystal substrate used to manufacture the IS capacitor can have a substrate area of, for example, 10 cm ² or more. As a result, the MIS capacitor can be made much cheaper than the conventional one. Although there is no particular upper limit on the area of the substrate, it is currently about 400 cm ² . As a result, semiconductor processes using Si wafers of 2 to 8 inches, particularly 6-inch type, are currently the mainstream, and it is possible to cope with this.

Next, the inside of the vacuum chamber is set to 10 ^-5 by a vacuum pump.
After evacuation to about Torr or higher, the single crystal substrate is heated.
The cleaned Si substrate has an active surface and is easily contaminated by residual gas in a vacuum. Therefore, during the temperature rise, the single crystal substrate is evacuated to a vacuum as high as possible in order to avoid contamination by foreign matters. There is no particular upper limit to the degree of vacuum (lower limit to the pressure), but in consideration of workability, it is usually about 10 ^-7 Torr. Further, as a method for avoiding contamination, it is effective to intentionally form an oxide protective layer such as SiO _{2 having} a layer thickness of about 0.5 to ₂ nm to protect the Si substrate. This oxide protective layer is usually removed just before film formation by reduction removal described later.
This oxide protective layer is formed in a vacuum chamber at a substrate temperature of 5
The temperature was raised to about 00 to 700 ° C, and the area near the substrate was 10 ^-4 to 10
It is preferable to introduce pure oxygen so as to be ^-2 Torr and perform thermal oxidation. The heating temperature during film formation is preferably 400 ° C. or higher for crystallization of ZrO ₂ .
Further, about 750 ° C. or higher has excellent crystallinity, and particularly 850 ° C. or higher is preferable in order to obtain the crystal level flatness of the molecular level film. Note that the upper limit of the heating temperature of the single crystal substrate is 1300.
It is about ℃.

Next, at least Zr of Zr and a rare earth metal (Pr is taken as an example here) is heated by an electron beam or the like to evaporate. At this time, introduction of an oxidizing gas described later into the vacuum chamber has not been performed yet.

Attention must be paid to the timing of supplying Zr and Pr and the oxidizing gas to the single crystal substrate. The optimum supply timing of oxygen is at least Zr of Zr and rare earth metals, converted to the thickness when all metal elements reaching the substrate surface form a metal thin film, and the total amount is 5
It is particularly desirable to supply the film having a thickness of less than or equal to nm, particularly 0.01 to 5 nm. This supply of Zr and the rare earth metal reduces and removes a small amount of oxide formed before film formation, and the substrate lattice information is ZrO ₂
Is transmitted to the film containing as a main component, and epitaxial growth is smoothly performed.

Taking the case of forming a YSZ film on a Si substrate as an example, the oxidation reaction of Zr metal and Pr metal is Zr + O ₂ = ZrO ₂ ΔG = -187.6 (kcal / mol) Pr + 3 / 4 O ₂ = 1/2 Pr ₂ O ₃ ΔG = -181.5 (kcal / mol), and the changes in free energy are both negative and large. That is, it is shown that Zr and Pr are easily oxidized and act as a reducing agent. Assuming a solid-state reaction with SiO ₂ on the Si substrate surface

SiO ₂ + Zr = ZrO ₂ + Si ΔG = −43.129 (kcal / mol) Considering from ΔG, SiO ₂ is reduced by Zr. The same applies to Pr. By this reaction, the oxide film on the substrate surface can be removed immediately before the film formation. That is, favorable ZZ epitaxial growth can be realized by supplying Zr + Pr metal before film formation of PSZ and then supplying oxygen, Zr, and Pr to grow PSZ. When the degree of non-oxidation of the substrate surface is good, the supply of the metal to the substrate by evaporation and the supply of the oxidizing gas may be performed simultaneously.

Next, a Zr metal, a rare earth metal (which will be represented by Pr in the following description) and an oxidizing gas are supplied to the single crystal substrate to obtain a thin film containing ZrO ₂ as a main component.
Here, the film formation rate is 0.05 to 1.00 nm / s, preferably 0.100 to 0.500 nm / s. The reason is that if it is too slow, the substrate will be oxidized, and if it is too fast, the crystallinity of the formed thin film will be poor and unevenness will occur on the surface. Therefore, the optimum film formation rate is determined by the amount of oxygen introduced. Therefore, prior to the vapor deposition of a thin film containing ZrO ₂ as a main component, how much each metal of Zr and Pr evaporates per unit time depending on the electric power condition applied to the vapor deposition source, and Zr, Pr, ZrO ₂ , PrO _x Whether or not the vapor-deposited film is formed is measured and calibrated for each metal by a film thickness meter installed near the substrate in the vacuum vapor deposition tank. As the oxidizing gas, oxygen, ozone, atomic oxygen, NO ₂ or the like can be used. Here, it is assumed that oxygen is used below. Oxygen is continuously discharged from the chamber with a vacuum pump, and 2 to 50 cc /
Minute, preferably 5 to 25 cc / min of oxygen gas is continuously jetted, and 10 ^-4 at least near the single crystal substrate in the vacuum chamber.
Create an oxygen atmosphere of about -10 ^-2 Torr. The optimum amount of oxygen is
Determine an appropriate flow rate in advance, depending on the size of the chamber, pumping speed of the pump, and other factors. Here, the upper limit of the oxygen gas pressure is set to 10 ^-2 Torr so that the metal source in the evaporation source in the vacuum chamber is not deteriorated and the evaporation rate is constant. Further, when introducing oxygen gas into the vacuum vapor deposition tank, it is preferable to inject oxygen gas onto the surface of the single crystal substrate from its vicinity to create an atmosphere with a high oxygen partial pressure only near the single crystal substrate, and to reduce oxygen The amount introduced can further promote the reaction on the substrate. At this time, since the vacuum chamber is continuously evacuated, most of the vacuum chamber is 10 ^-4 -10.
^-6 Torr low pressure. 1 cm of single crystal substrate
^In a narrow region of about ² , the oxidation reaction can be promoted on the single crystal substrate by this method, but in order to form a film with a substrate area of 10 cm ² or more, for example, a large single crystal substrate area of 2 inches in diameter, By rotating the substrate as in 1 and supplying a high oxygen partial pressure to the entire surface of the substrate, a film can be formed in a large area. At this time, the rotation speed of the substrate is preferably 10 rpm or more. This is because when the rotation speed is slow, the composition distributions of Zr, Pr, and O occur in the film thickness direction and in the plane. There is no particular upper limit to the rotation speed of the substrate, but it is usually about 120 rpm due to the mechanism of the vacuum device.

Rare earth metal (including Y) to ZrO ₂
Has the following effects.

From the high temperature, ZrO ₂ simple substance is cubic crystal → tetragonal crystal →
It undergoes a phase transition with monoclinic crystals at room temperature. Stabilized zirconia is obtained by adding a rare earth metal (including Y) in order to stabilize the cubic crystal. In order to epitaxially grow ZrO ₂ on Si and further epitaxially grow a second oxide thin film, a rare earth oxide thin film, on ZrO 2.
₂ is preferably a cubic crystal with high symmetry. Therefore, each metal element of Zr and rare earth metal (including Y) is simultaneously evaporated from separate evaporation sources while controlling the ratio of Zr / rare earth metal to be deposited on the single crystal substrate. Here, the rare earth metal (including Y) / Zr molar ratio from the evaporation source is 0 to
It is preferably 3.0, preferably 0.25 to 1.0. As a result, the first oxide thin film having the above preferable composition ratio can be obtained. As described above, when the graded composition portion is provided in the first oxide thin film, Zr
It is preferable to gradually reduce the supply amount of the above, and finally to zero, and then shift to the formation of the second oxide thin film.

Then, the supply of Zr from the evaporation source is stopped and only the rare earth metal is supplied to form the second oxide thin film. At this time, the atmospheric conditions, particularly the oxidizing gas introduction conditions, the substrate rotation conditions, the substrate temperature conditions, etc., are the same as those in the above first
It may be the same as when forming the oxide thin film.

Although the manufacturing method has been described in detail above, this manufacturing method has no room for inclusion of impurities and is controlled, as is particularly clear when comparing the conventional vacuum deposition method, sputtering method and laser ablation method. Since it can be carried out under easy operating conditions, it is suitable for obtaining a target substance having high reproducibility and high integrity in a large area. Furthermore, this method is
Even if the BE apparatus is used, the target thin film can be obtained in exactly the same manner.

The MIS capacitor material obtained as described above is formed with electrodes and finely processed by a semiconductor process to obtain a large number of MIS capacitors. The MIS capacitor of the present invention hardly causes hysteresis in the C-V characteristic, and even if the hysteresis occurs, the hysteresis is 0.8 V in the voltage width at half the C value (hereinafter referred to as the hysteresis value). It is below the level. In addition, MIS (Metal-Insulator-Semico
The apparent dielectric constant of the insulating layer (Insulator) of the nductor structure can be increased to about 20. The MIS capacitor as described above can be used as a FET for DRAM. Compared with a conventional MIS capacitor using SiO ₂ as an insulating layer, the MIS capacitor of the present invention has an insulating layer having a dielectric constant of 10 to 20, which is 5 to 10 times that of the conventional MIS capacitor. It is possible to further increase the degree.

Further, a ferroelectric material is formed on the second oxide thin film of the MIS capacitor material, and a semiconductor process such as electrode formation and microfabrication is performed to obtain a ferroelectric gate FE.
It can be used as T, and a nonvolatile memory can be realized. By optimally selecting the crystal of the second oxide film material and the crystal of the ferroelectric material, an epitaxial structure can be realized, and the disturbance of the physical quantity due to the grain boundary is eliminated and a good function is exhibited. Further, by providing a floating gate in the dielectric material used for this MIS capacitor, it can be applied as a tunnel oxide film material used for a basic cell such as a flash memory. The present invention relates to other MOS
It can be used as a capacitor for devices and semiconductor elements and has great value.

[0041]

EXAMPLES The present invention will be described in more detail below by showing specific examples of the present invention.

Example 1 As a single crystal substrate on which an oxide thin film was grown, a Si single crystal wafer which was cut so that its surface was a (100) plane and mirror-polished was used. After purchase, the mirror surface was cleaned by etching with a 40% ammonium fluoride aqueous solution.
A circular substrate having a diameter of 2 inches was used as the Si substrate.

The above single crystal substrate was fixed on a substrate holder equipped with a rotation and heating mechanism installed in a vacuum chamber, and the vacuum deposition chamber was evacuated to 10 ^-6 Torr by a pump. After that, in order to protect the cleaned surface of the substrate with Si oxide, 6
At 00 ° C., oxygen was introduced into the vicinity of the substrate from a nozzle at a rate of 25 cc / min, and a Si oxide film of about 1 nm was formed on the substrate surface by thermal oxidation. Then, the vacuum deposition tank is again set to 10 ^-6 To
After exhausting to rr, the substrate was heated to 900 ° C. and rotated. The rotation speed was 20 rpm.

Thereafter, the metals Zr and Pr were simultaneously supplied from independent evaporation sources while controlling the Pr / Zr molar ratio to 0.45. At this time, oxygen is not introduced. When the supply amount is converted to the film thickness of Zr + Pr alloy and reaches 0.2 nm, oxygen gas is introduced from the nozzle at a rate of 25 cc / min to react metal and oxygen with PSZ (Zr of about 25 nm thickness).
A film in which O ₂ was doped with Pr) was formed.

Then, the Zr evaporation source was stopped and Pr oxide was deposited to a thickness of 25 nm by supplying only the Pr evaporation source to obtain a two-layer film of PSZ and Pr oxide (film structure of sample No. 1). Further, when forming the first oxide thin film, the film having a Pr / Zr molar ratio of 0.45 was formed to 10 nm, a uniform composition layer of 10 nm was formed, and then Zr supply was gradually reduced. The gradient composition layer was formed to have a thickness of 30 nm so as to be zero, and a 10 nm-thick Pr oxide thin film was formed on the gradient composition layer (the film structure of Sample No. 2). Further, in the vacuum chamber, in addition to the Zr evaporation source and the Pr evaporation source, other rare earth metals R ′, that is, Y, La, Ce, Nd, Sm,
An evaporation source of one of Eu, Gd, Tb, Dy, Ho, Er and Yb is arranged, and after stopping the Zr evaporation source, one of the rare earth metals R ′ is supplied instead of Pr,
An R'oxide having a film thickness of 25 nm was formed to obtain a two-layer film of PSZ and R'oxide (the film structure of Sample Nos. 3 to 14). In addition, in these sample Nos. 3 to 14, the composition of the first oxide thin film was the same as that of the sample No. 1. Furthermore, Zr
After stopping the evaporation source, Gd is simultaneously supplied in addition to Pr,
A 25 nm film of Pr and Gd composite oxide was formed to form PSZ and Pr.
And a Gd complex R oxide two-layer film was obtained (Sample No. 15
Membrane structure).

FIG. 2 shows the result of X-ray measurement of the thin film obtained in Sample No. 1 (hereinafter, this may be referred to as a two-layer film). In the figure, the (002) peak of PSZ is clearly observed. This peak is 25
It is understood that the diffraction is from the PSZ crystal having a thickness of nm, and a crystal film strongly oriented in an orientation reflecting the crystal structure and symmetry of the Si substrate is obtained. Furthermore, a peak is seen on the left side of this peak. This is a peak of Pr oxide, and it can be seen that a crystal film strongly oriented in an orientation reflecting the crystal structure and symmetry of PSZ, similar to PSZ, is obtained.

Further, FIG. 3 shows the RHEED (R
eflection High Energy Electron Diffraction) pattern. The incident direction of the electron beam is shown from the [110] direction and the [100] direction of the Si substrate. As can be seen from these results, in the diffraction pattern on the surface of the thin film having this structure, spots showing a fluorite type having a PrO ₂ crystal structure are obtained, and it is understood that the film is formed of a single crystal.

A thin film having a gradient composition obtained in Sample No. 2 (hereinafter, this thin film is referred to as a gradient composition film, and the thin film obtained in Sample No. 1 may be referred to as a two-layer film). The RHEED pattern is shown in FIG. It can be seen that the diffraction pattern on the surface of the thin film of this structure has a sharp spot and a streak shape as compared with the case of the two-layer film of FIG. From this, it is found that the film is a single crystal and the surface flatness is further excellent. That is, the graded composition film is superior to the two-layer film in crystallinity. This is because there is some misfit of the lattice between the first oxide thin film and the second oxide thin film in the above two-layer film, but in the gradient composition film,
Since the composition gradually changes and the misfit no longer exists, it is considered that a highly crystalline epitaxial film can be obtained.

Next, a Pt electrode film having an area of about 0.15 mm ² was formed on the Pr oxide surface on the outermost surface of the above structure film, and used as an upper electrode, and a MIS capacitor having an ohmic electrode made of Al provided on the Si wafer was formed. It was made. Also, PSZ
And the conventional YSZ-only epitaxial dielectric MIS capacitors were designated as sample Nos. 16 and 17, respectively. The Si wafer is a 5Ωcm p-type wafer.

CV characteristics of the MIS capacitors of Sample Nos. 1 to 17 are shown in FIGS. The C-V characteristic was measured at 1 MHz while changing the bias voltage at 0.4 V / sec. As is clear from the CV characteristics shown in these figures, in the present invention, Pr, Ce, Nd, Gd, Tb and D selected as the rare earth metal species of the second oxide thin film were selected.
Sample No. 1, 2, 5 using y, Ho and Er,
6, 9, 10, 11, 12, 13, and 15 (Pr + G
In d), there was no hysteresis in the C-V characteristics, or the hysteresis width value was 0.8 V or less. On the other hand, sample Nos. 3, 7, 8 and 14 in which a rare earth metal species other than the above is used for the second oxide thin film,
And sample No. 1 without the second oxide thin film
In 6 and 17, the hysteresis value is about 1.5V
A large hysteresis width value was seen as above. Note that La
In the sample No. 4 in which No. 4 was used, the hysteresis width value was relatively small, but the hysteresis curves intersected with each other, and a small C value peak was present in the middle, and the capacitance change curve became gentle. The C-V curve of the MIS device element has no hysteresis and needs to have a sharp change. Although not shown in the figure, in sample No. 4 using La, the RHEED pattern on the surface of the thin film became a ring or a halo, and it was not recognized that perfect epitaxial growth was performed.

For the sake of clarity, the hysteresis values for each sample are summarized in Table 1. Example 2 described next
Table 1 also shows the hysteresis value of the sample.

[0052]

[Table 1]

Example 2 In a vacuum chamber, a Zr evaporation source and a rare earth metal R, that is, Y, La, Ce, Pr, Nd, Sm, Eu, Gd, T were used.
An evaporation source of one of b, Dy, Ho, Er and Yb is arranged, and first, Zr and the rare earth metal R, that is, Y and L
a, Ce, Pr, Nd, Sm, Eu, Gd, Tb, D
One of y, Ho, Er and Yb is supplied to form a layer of ZrO ₂ doped with R on the substrate to a thickness of 10 nm, then the supply of Zr is gradually reduced, and finally the amount of Zr is zero. As described above, a composition gradient layer having a thickness of 30 nm is formed to form a first oxide thin film, and then an R oxide thin film having a thickness of 10 nm is formed as a second oxide thin film.
o. A thin film of 18-30 was formed. The thin films of these samples were also subjected to crystal evaluation by RHEED in the same manner as above. Sample No. 18-30 thin film RHE
The ED patterns are shown in FIGS. In these figures, (a) shows the incident direction of the electron beam from the [110] direction of the Si substrate, and (b) shows the incident direction of the electron beam from the [100] direction of the Si substrate. Indicated.

As can be seen from these RHEED patterns, in the sample using Ce, Pr, Nd, Gd, Tb, Dy, Ho and Er selected in the present invention as the rare earth metal of the second oxide thin film, the single crystal was used. It was confirmed that epitaxial growth could be realized because the spot pattern showing “” was obtained. However, La, Sm, Eu, Yb
It was confirmed that even if the first oxide thin film and the second oxide thin film had the same rare earth metal, the RHEED pattern became a ring or a halo, and epitaxial growth was impossible. It should be noted that when Y is used, epitaxial growth is possible, but a large hysteresis is observed in the CV characteristic as described later.

Further, electrodes were provided on the thin films of the above samples in the same manner as in Example 1 above to prepare sample Nos. 18 to 30, and these samples were subjected to CV in the same manner as in Example 1.
When the characteristics were examined, the CV characteristics shown in FIGS. 35 to 47 were obtained. As in the case of Example 1 above, the samples using Ce, Pr, Nd, Gd, Tb, Dy, Ho, and Er selected in the present invention have no hysteresis as shown in Table 1. But it was very small. However, when using other rare earth metals,
Even if the rare earth metals of the first oxide thin film and the second oxide thin film were the same, the hysteresis was extremely larger than that of the present invention. In addition, sample No. using La.
In No. 4, the hysteresis width value was relatively small, but when the hysteresis curves crossed, a peak with a small C value appeared in the middle, and the capacitance change became slow.

[0056]

As described above, the multilayer film according to the present invention has a structure in which an epitaxial oxide film of a specific rare earth metal is formed on an epitaxial oxide film of the composition Zr _1-x R _x O ₂ -δ. Therefore, like the YSZ film, C
Good MOS characteristics can be obtained without showing hysteresis in the −V characteristics. This MIS structure is extremely useful as a MIS capacitor for Si devices.

[Brief description of drawings]

FIG. 1 is a diagram showing an example of a vapor deposition apparatus used in a method for manufacturing an electronic device substrate of the present invention.

FIG. 2 is an X-ray diffraction diagram of the film structure of Sample No. 1 obtained on a single crystal substrate.

FIG. 3 is a drawing-substituting photograph showing a crystal structure of a thin film of Sample No. 1, showing a reflected high-energy electron diffraction pattern when an electron beam is incident from [110] and [100] directions of a Si single crystal substrate. FIG.

FIG. 4 is a drawing-substituting photograph showing a crystal structure of a thin film of Sample No. 2, showing a reflection high-energy electron diffraction pattern when an electron beam is incident from [110] and [100] directions of a Si single crystal substrate. FIG.

FIG. 5 is a graph showing the CV characteristics of the MIS capacitor of sample No. 1.

FIG. 6 is a graph showing the CV characteristics of the MIS capacitor of sample No. 2.

FIG. 7 is a graph showing the CV characteristics of the MIS capacitor of sample No. 3.

FIG. 8 is a graph showing the CV characteristics of the MIS capacitor of sample No. 4.

FIG. 9 is a graph showing the CV characteristics of the MIS capacitor of sample No. 5.

FIG. 10: C-V of MIS capacitor of sample No. 6
It is a graph which shows a characteristic.

FIG. 11 C-V of MIS capacitor of sample No. 7
It is a graph which shows a characteristic.

FIG. 12: C-V of MIS capacitor of sample No. 8
It is a graph which shows a characteristic.

FIG. 13: CV of MIS capacitor of sample No. 9
It is a graph which shows a characteristic.

FIG. 14 C- of the MIS capacitor of sample No. 10
It is a graph which shows V characteristic.

FIG. 15 C- of the MIS capacitor of sample No. 11
It is a graph which shows V characteristic.

FIG. 16 C- of the MIS capacitor of sample No. 12
It is a graph which shows V characteristic.

FIG. 17 C- of the MIS capacitor of sample No. 13
It is a graph which shows V characteristic.

FIG. 18 C- of the MIS capacitor of sample No. 14
It is a graph which shows V characteristic.

FIG. 19 C- of the MIS capacitor of sample No. 15
It is a graph which shows V characteristic.

FIG. 20 C- of the MIS capacitor of sample No. 16
It is a graph which shows V characteristic.

FIG. 21 C- of the MIS capacitor of sample No. 17
It is a graph which shows V characteristic.

FIG. 22 is a drawing-substituting photograph showing the crystal structure of the thin film of Sample No. 18, showing a reflected high-energy electron diffraction pattern when an electron beam is incident from [110] and [100] directions of a Si single crystal substrate. FIG.

23 is a drawing-substituting photograph showing the crystal structure of a thin film of Sample No. 19, showing a reflected high-energy electron diffraction pattern when an electron beam is incident from the [110] and [100] directions of a Si single crystal substrate. FIG.

FIG. 24 is a drawing-substituting photograph showing a crystal structure of a thin film of Sample No. 20, showing a reflection high-energy electron diffraction pattern when an electron beam is incident from [110] and [100] directions of a Si single crystal substrate. FIG.

25 is a drawing-substituting photograph showing the crystal structure of the thin film of Sample No. 21, showing a reflected high-energy electron diffraction pattern when an electron beam is incident from [110] and [100] directions of a Si single crystal substrate. FIG.

FIG. 26 is a drawing-substituting photograph showing the crystal structure of the thin film of Sample No. 22, showing a reflection high-energy electron diffraction pattern when an electron beam is incident from the [110] and [100] directions of a Si single crystal substrate. FIG.

FIG. 27 is a drawing-substituting photograph showing the crystal structure of the thin film of Sample No. 23, which shows a reflection high-energy electron diffraction pattern when an electron beam is incident from the [110] and [100] directions of a Si single crystal substrate. FIG.

28 is a drawing-substitute photograph showing the crystal structure of a thin film of Sample No. 24, which shows a reflection high-energy electron diffraction pattern when an electron beam is incident from [110] and [100] directions of a Si single crystal substrate. FIG.

FIG. 29 is a drawing-substituting photograph showing the crystal structure of the thin film of Sample No. 25, which shows a reflected high-energy electron diffraction pattern when an electron beam is incident from the [110] and [100] directions of a Si single crystal substrate. FIG.

FIG. 30 is a drawing-substituting photograph showing the crystal structure of the thin film of Sample No. 26, which shows a reflected high-energy electron diffraction pattern when an electron beam is incident from the [110] and [100] directions of a Si single crystal substrate. FIG.

FIG. 31 is a drawing-substituting photograph showing a crystal structure of a thin film of Sample No. 27, which shows a reflection high-energy electron diffraction pattern when an electron beam is incident from [110] and [100] directions of a Si single crystal substrate. FIG.

FIG. 32 is a drawing-substituting photograph showing a crystal structure of a thin film of Sample No. 28, showing a reflected high-energy electron diffraction pattern when an electron beam is incident from [110] and [100] directions of a Si single crystal substrate. FIG.

FIG. 33 is a drawing-substituting photograph showing a crystal structure of a thin film of Sample No. 29, which shows a reflection high-energy electron diffraction pattern when an electron beam is incident from [110] and [100] directions of a Si single crystal substrate. FIG.

FIG. 34 is a drawing-substituting photograph showing a crystal structure of a thin film of Sample No. 30, showing a reflected high-energy electron diffraction pattern when an electron beam is incident from [110] and [100] directions of a Si single crystal substrate. FIG.

FIG. 35 is C- of the MIS capacitor of sample No. 18.
It is a graph which shows V characteristic.

FIG. 36 is C- of the MIS capacitor of sample No. 19.
It is a graph which shows V characteristic.

FIG. 37 is C- of the MIS capacitor of sample No. 20.
It is a graph which shows V characteristic.

FIG. 38 is C- of the MIS capacitor of sample No. 21.
It is a graph which shows V characteristic.

FIG. 39 is C- of the MIS capacitor of sample No. 22.
It is a graph which shows V characteristic.

FIG. 40: C- of MIS capacitor of sample No. 23
It is a graph which shows V characteristic.

FIG. 41 is C- of the MIS capacitor of sample No. 24.
It is a graph which shows V characteristic.

FIG. 42 is C- of the MIS capacitor of sample No. 25.
It is a graph which shows V characteristic.

FIG. 43 C- of the MIS capacitor of sample No. 26
It is a graph which shows V characteristic.

FIG. 44 is C- of the MIS capacitor of sample No. 27.
It is a graph which shows V characteristic.

FIG. 45 is C- of the MIS capacitor of sample No. 28.
It is a graph which shows V characteristic.

FIG. 46 is C- of the MIS capacitor of sample No. 29.
It is a graph which shows V characteristic.

FIG. 47 C- of MIS capacitor of sample No. 30
It is a graph which shows V characteristic.

[Explanation of symbols]

 1 Vapor Deposition Device 1a Vacuum Chamber 2 Single Crystal Substrate 3 Holder 4 Rotating Shaft 5 Motor 6 Heater 7 Oxidizing Gas Supply Device 8 Oxidizing Gas Supply Port 9 Zr Evaporating Part 10 Rare Earth Metal Evaporating Part

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI technical display location C30B 25/16 H01L 29/43

Claims (12)

[Claims] 1. A Si single crystal semiconductor substrate and a composition Zr _1-x R _x O _2- δ formed on the semiconductor substrate.
(Here, R is a rare earth metal containing Y, and 0 ≦ x <1
A first oxide thin film in which x in the composition formula is 0 to 0.75, at least in a substrate adjacent layer portion adjacent to the semiconductor substrate. Ce, Pr, Nd, formed on the first oxide thin film,
A MIS capacitor, comprising: a second oxide thin film, which is an epitaxial film whose main component is an oxide of at least one rare earth metal selected from Gd, Tb, Dy, Ho, and Er. 2. The MIS capacitor according to claim 1, wherein the rare earth metal of the first oxide thin film and the rare earth metal of the second oxide thin film are the same. 3. A remaining layer portion other than the substrate adjacent layer portion of the first oxide thin film, wherein the remaining layer portion,
The Zr content is equal to the Zr content of the layer adjacent to the substrate and the second
3. The M of claim 2 set between the Zr contents of the oxide thin film.
IS capacitor. 4. The remaining layer portion of the first oxide thin film is Z
The MIS capacitor according to claim 3, wherein the r content is a graded composition thin film in which the r content is gradually reduced between the Zr content of the adjacent layer portion of the substrate and the Zr content of the second oxide thin film. 5. The method for manufacturing a MIS capacitor according to claim 1, wherein the vacuum chamber is initially evacuated to a vacuum of 1 × 10 ⁻⁵ Torr or less, and the Si single crystal substrate is kept at a predetermined temperature in this state. Then, at least Zr of Zr and each metal element of at least one rare earth metal (including Y) is simultaneously evaporated from separate evaporation sources while controlling the ratio of Zr and rare earth metal. A metal is supplied to the substrate surface of the crystal substrate, an oxidizing gas is introduced into the vacuum chamber at the same time as or after a delay of a predetermined time from the metal supply, and the atmosphere in the vacuum chamber at least near the single crystal substrate is set to 1 × 10 ^-4 to 1 × 10 ^-2 To
rr, and at least after the introduction of the oxidizing gas, they are simultaneously vaporized while controlling the ratio of Zr and the rare earth metal, and the first oxide thin film or the first oxide thin film and the gradient composition are formed on the substrate surface of the single crystal substrate. The thin film is formed by epitaxial growth, and then the evaporation of Zr is stopped and only the rare earth metal is evaporated while maintaining the introduction of the oxidizing gas, and the second oxide is formed on the first oxide thin film or the gradient composition thin film. A method of manufacturing a MIS capacitor, which comprises forming a thin film by epitaxial growth. 6. The MIS capacitor according to claim 5, wherein an oxidizing gas is injected from the vicinity of the surface of the single crystal substrate to create an atmosphere having a partial pressure of the oxidizing gas higher than other portions only in the vicinity of the single crystal substrate. Manufacturing method. 7. The single crystal substrate has a substrate surface area of 10
By making the surface area cm ² or more and rotating in the plane of the substrate, the oxidizing gas high partial pressure atmosphere is provided over the entire single crystal substrate, and is substantially uniform over the entire surface of the single crystal substrate. The method for manufacturing a MIS capacitor according to claim 6, wherein an oxide thin film is formed. 8. A Si single crystal is used as the single crystal substrate,
8. The method for manufacturing a MIS capacitor according to claim 5, wherein the (100) plane is used as a substrate surface. 9. The single crystal substrate is made of Si single crystal and S.
9. The method for manufacturing a MIS capacitor according to claim 5, wherein a substrate having an i oxide protection film formed thereon is used. 10. The method for manufacturing a MIS capacitor according to claim 5, wherein the single crystal substrate is heated to 750 ° C. or higher. 11. The predetermined time from the supply of the metal by evaporation to the introduction of the oxidizing gas is a time corresponding to 5 nm or less in terms of the film thickness of the metal thin film formed on the single crystal substrate. 11. The method for manufacturing a MIS capacitor according to any one of 5 to 10. 12. When forming the first oxide thin film, first, a ratio of Zr to the rare earth metal is set to a predetermined value and simultaneously evaporated to form a uniform composition having a predetermined ratio of Zr to the rare earth metal and a predetermined thickness. 12. The method for manufacturing a MIS capacitor according to claim 5, wherein a layer is formed, and thereafter, the evaporation amount of Zr is gradually reduced to form a graded composition layer in which the Zr content is gradually reduced.