JPH06232391A - Semiconductor device and its manufacture - Google Patents

Abstract

PURPOSE:To provide a semiconductor device and its manufacturing method wherein the increase of thickness of a gate oxide film is prevented, the deterioration of a gate oxide film is prevented, and the designed characteristics of a device can be obtained. CONSTITUTION:On an Si substrate 11, a gate oxide film 12 is formed, thereon a polycrystalline Si film 21 is formed, and thereon a tungsten silicide film 24 is formed. Crystal grains 21a, 21b, 21c constituting the polycrystalline Si film 21 have columnar textures stretching in the film thickness direction. Further crystal structure wherein the crystal grain interval viewed from the vertical direction is larger than the thickness of the polycrystalline Si film 21 is obtained.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor device and a manufacturing method thereof, and more particularly to a semiconductor device having a polycide structure and a manufacturing method thereof.

[0002]

2. Description of the Related Art Conventionally, as a gate electrode of a MOS transistor, a polycrystalline Si film and a silicide film (Si and refractory metal) formed on the polycrystalline Si film have been used to reduce the resistance of the gate electrode. An electrode having a polycide structure composed of a film formed of an alloy of

A gate having this conventional polycide structure
A method of forming electrodes will be described with reference to FIG. Figure 7
Is a step of forming a gate electrode having a polycide structure
FIG. Gate electrode with polycide structure
In order to form the pole 10, first, on the Si substrate 11,
SiO formed₂ On the gate oxide film 12 made of
SiH by low pressure CVD method_Four Pyrolysis (about 620 ℃)
Then, a polycrystalline Si film 13 having a film thickness of 1500 Å is formed.
(FIG. 7 (a)). Next, on the polycrystalline Si film 13,
WF₆ Gas and SiH_Four CVD method using gas (about 450
℃), WSi which is a mixture of W and Si_x The membrane 14
A film thickness of 1500Å is formed (FIG. 7B). Then polycrystal
Si film 13 and WSi_x A semiconductor device having the film 14 formed thereon,
The polycrystalline Si film 13 and WSi are heat treated at about 900 ° C._x film
The alloy of Si and W is formed between
The side film 15 is formed (FIG. 7C). Then polycrystal
Si film 13, WSi _x Membrane 14 and Tungsten Silica
By etching the id film 15 into a predetermined shape,
A gate electrode 10 having a polycide structure is formed (FIG.
7 (d)). Polycide structure using this low pressure CVD method
The method of forming the
The more valuable devices are, the higher their utility value is.
It

[0004]

The above low pressure CVD method is used.
In the method of forming the polycide structure, the WSi_x The membrane 14
In the process of forming, WF₆ F in gas is polycrystalline Si film 13
Diffuse through and penetrate the Si substrate 11 and the gate oxide film 12.
To enter. In addition, WSi formed by the low pressure CVD method _x Membrane 1
4 contains a high concentration of F, and as a result, the heat treatment of the subsequent process
In theory, WSi_x F in the film 14 is a polycrystalline Si film 1
3 and diffuses into the gate oxide film 12. Si
O₂ When F enters the gate oxide film 12 made of
SiO by F₂ Bond is cut and free oxygen is generated
Jijiru This oxygen is the Si or polycrystalline Si film in the Si substrate 11.
SiO by reacting with Si in 13₂ Formed
As a result, the physical film thickness of the gate oxide film 12 (physical
The film thickness. ) And electrical film thickness (physical film thickness does not change)
The film thickness is equivalent to the change in gate capacitance. Below
Is simply the physical thickness and the electrical thickness.
U ) Increases. This rate of increase is the initial gate oxide
2 can reach about 15% of the thickness of this gating acid
The gate capacitance decreases due to the increase in the film thickness of the oxide film 12.
Also, SiO₂ Of the gate oxide film because the bond of
The film quality deteriorates and the gate breakdown voltage decreases. this
Therefore, the device characteristics as designed cannot be obtained.
There is a title (IEEE Vol. 12, pages 623-625).
See page).

In view of the above circumstances, the present invention prevents the increase in the film thickness of the gate oxide film, prevents the deterioration of the film quality of the gate oxide film, and obtains the device characteristics as designed and the manufacturing thereof. The purpose is to provide a method.

[0006]

The present inventor has conducted various experiments and researches in order to achieve the above-mentioned object. As a result, the invasion of Si into a Si substrate or a gate oxide film is eliminated by eliminating a passage through which F can easily diffuse. As a result, they have found that the amount of F can be reduced, and the present invention has been completed. Specifically, the semiconductor device of the present invention is a semiconductor device having a polycide structure including a polycrystalline Si film and a refractory metal silicide film formed on the polycrystalline Si film, wherein the polycrystalline Si film is A part or all of the structure of the polycrystalline Si film has a columnar structure extending in the film thickness direction, and the grain boundary spacing as viewed from the vertical cross-sectional direction of the polycrystalline Si film is not less than the film thickness of the polycrystalline Si film. It is characterized by having a certain crystal structure.

A method of manufacturing a semiconductor device according to the present invention is
In a method of manufacturing a semiconductor device having a polycide structure, (1) an oxide film is formed on a substrate of the semiconductor device,
(2) forming an amorphous Si film on the oxide film,
(3) A polycrystalline Si film is formed on the amorphous Si film, (4) Impurity for implanting the amorphous Si film into an electrode is injected into the polycrystalline Si film, and (5) Impurity is injected into the polycrystalline Si film. A polycide structure is formed by forming a refractory metal silicide film on the formed polycrystalline Si film.

Here, instead of the steps (3) and (4), (6) the substrate on which the amorphous Si film is formed is heat-treated to make at least a part of the amorphous Si film a polycrystalline Si film, (7) Impurities for using the polycrystalline Si film as an electrode may be implanted into the polycrystalline Si film. At this time, the upper portion of the polycrystalline Si film is made amorphous by the implantation of impurities, but some crystals may remain.

Further, in place of the steps (3) and (4), (8) the amorphous Si film is formed on the amorphous Si film.
Impurities for using the film as an electrode may be implanted, and (9) at least a part of the amorphous Si film may be made into a polycrystalline Si film by heat-treating the substrate on which the amorphous Si film is formed.

Further, instead of the steps (3), (4), and (5), (10) a film made of refractory metal and Si is formed on the amorphous Si film, and (11) the high melting point is formed. The substrate on which the film made of metal and Si is formed is heat treated, and (1
2) A polycide structure may be formed by forming a refractory metal silicide film.

Further, instead of the step of forming an amorphous Si film on the oxide film, (13) a polycrystalline Si film is formed on the oxide film, and (14) an amorphous Si film is formed on the polycrystalline Si film. May be formed. Furthermore, the refractory metal silicide film is preferably a tungsten silicide film. In addition, a tantalum silicide film, a nickel silicide film, a molybdenum silicide film, a platinum silicide film, a titanium silicide film, a chromium silicide film, a manganese silicide film, a cobalt silicide film, or the like can be used as the refractory metal silicide film.

[0012]

According to the semiconductor device of the present invention, a part or the whole of the structure of the polycrystalline Si film formed under the refractory metal silicide film has a columnar structure extending in the film thickness direction, and the polycrystalline Si film has a columnar structure. Since the crystal grain boundary spacing seen from the direction of the vertical cross section of the film is larger than the film thickness of this polycrystalline Si film, the WF used for forming the refractory metal silicide film on this polycrystalline Si film. There are few passages through which F in the ₆ gas and F in the refractory metal silicide film can diffuse. As a result, in the polycrystalline Si film of the semiconductor device of the present invention, the grain boundary diffusion of F can be reduced as compared with the conventional polycrystalline Si film.

In the method for manufacturing a semiconductor device of the present invention, an amorphous Si film is formed in advance, and a refractory metal silicide film is formed on the amorphous Si film. Since amorphous Si has no grain boundaries, F in the WF ₆ gas used for forming the refractory metal silicide film and F in the refractory metal silicide film cannot easily diffuse in the amorphous Si film. In addition, amorphous S
When a large grain size polycrystalline Si film is formed by heat-treating the i film, F cannot be easily diffused in the large grain size polycrystalline Si film as described above. Therefore, F penetrating the Si substrate and the gate oxide film is suppressed, and free oxygen generated by breaking the SiO ₂ bond of the gate oxide film is almost eliminated. As a result, there is almost no increase in the thickness of the gate oxide film, the reduction of the gate capacitance and the deterioration of the gate breakdown voltage are prevented, and the device characteristics as designed can be obtained.

[0014]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a sectional view showing an example of a semiconductor device having a polycide structure of the present invention. In this semiconductor device,
A gate oxide film 12 is formed on the Si substrate 11, a polycrystalline Si film 21 is formed on the gate oxide film 12,
A tungsten silicide film 24 is formed on the polycrystalline Si film 21. Here, as shown in FIG. 1, each of the crystal grains 21a, 21b, and 21c forming the polycrystalline Si film 21 has a columnar structure extending in the film thickness direction, and the crystal grain boundary spacing viewed from the vertical cross-sectional direction. Is more than the film thickness of the polycrystalline Si film 21. Therefore, this polycrystalline Si film 21
In particular, there are few passages through which F in the WF ₆ gas used for forming the tungsten silicide film 24 and F in the tungsten silicide film can easily diffuse. As a result, in the polycrystalline Si film 21 of this semiconductor device, the conventional polycrystalline S film 21
The grain boundary diffusion of F can be reduced as compared with the i film. As a result, the film thickness increase amount of the gate oxide film of this embodiment is 0.3 nm, whereas the film thickness increase amount of the conventional gate oxide film is 1.1 nm. be able to.

Next, referring to FIG. 2, the semiconductor device of the present invention.
A first embodiment of the manufacturing method will be described. FIG. 2 illustrates the invention.
Depending on the method of manufacturing the semiconductor device, the gate of the MOS transistor is
FIG. 7 is a cross-sectional view showing a process of manufacturing a cathode electrode. Si substrate 1
1 at 900 ° C. using well-known thermal oxidation method
The oxide film 31 is formed to a thickness of 10 nm (FIG. 2A).
The gate oxide film 31 is formed by the low pressure CVD method.
May be. Next, SiH is formed by the low pressure CVD method._Four With gas
Amorphous Si film 32 having a thickness of 100 nm at 550 ° C.
Formed (FIG. 2B). This amorphous Si film 32
Formation of Si₂ H₆ Even at 480 ° C using gas
Good. Next, using a low pressure CVD method at 620 ° C., polycrystal
The Si film 33a is formed with a film thickness of 50 nm. At this time, ammo
The Rufus Si film 32 is crystallized to form the large grain polycrystalline Si film 3
It becomes 3b. As a result, the polycrystalline Si film 33a having a small grain size is formed.
The polycrystalline Si film 33 made of the large grain size polycrystalline Si film 33b is
Formed (FIG. 2C). The amorphous Si film 3
Part of 2 may remain amorphous
It Next, the polycrystalline Si film 33 is coated with 7 × 10¹⁵c
m^-2, Phosphorous is ion-implanted at 30 KeV. As a result,
A part of the crystalline Si film 33 is made amorphous and a part of the amorphous Si film 33 is made amorphous.
It becomes the Si film 33A made into a mask (FIG. 2 (d)). next,
WF by low pressure CVD method₆ Gas and SiH _Four Using gas 4
WSi which is a mixture of W and Si at 50 ° C_2.8 The membrane 34
A film thickness of 150 nm is formed (FIG. 2E). Then 5%
O₂ + 95% N₂ Heat treatment in a gas atmosphere at 800 ° C for 10 minutes
And partially solidify the amorphous Si film 33A.
Converted to WSi_2.8 The film 34 is silicidized. this
When WSi_2.8 Part of F in the film 34 becomes amorphous
It diffuses into the Si film 33A.
Polycrystal formed by solid-phase crystallization of siliconized Si film 33A
The Si film has a large grain size, and is more amorphous than F diffusion.
It is faster that the first Si film 32 is a polycrystalline Si film having a large grain size.
Therefore, F does not diffuse in the large-grain polycrystalline Si film.
It Since a large grain size polycrystalline Si film has few crystal grain boundaries,
The amount of F diffused into the gate oxide film is reduced, and as a result,
The increase in electrical film thickness of the oxide film is reduced. After heat treatment
Is patterned by a well-known method.
Form a pole.

When the conventional polycrystalline Si film is formed to form the gate electrode, the electrical film thickness increase of the gate oxide film is 1.1 nm, but the large grain size of the first embodiment described above is large. When the crystalline Si film is formed, the electrical film thickness increase of the gate oxide film becomes 0.3 nm, and the film thickness increase amount can be suppressed to less than half that of the conventional one. Be uniform.

Next, a second embodiment of the method for manufacturing a semiconductor device of the present invention will be described with reference to FIG. FIG. 3 is a cross-sectional view showing a step of manufacturing a gate electrode of a MOS transistor by the method of manufacturing a semiconductor device according to the present invention. Si substrate 1
A gate oxide film 31 having a film thickness of 10 nm is formed on the substrate 1 at 900 ° C. by using a well-known thermal oxidation method (FIG. 3A).
The gate oxide film 31 may be formed by using the low pressure CVD method. Next, the amorphous Si film 32 is formed to a thickness of 150 nm at 550 ° C. using SiH ₄ gas by the low pressure CVD method.
Formed (FIG. 3B). This amorphous Si film 32
May be formed at 480 ° C. using Si ₂ H ₆ gas. Next, it is annealed at 650 ° C. for 2 hours in an N ₂ gas atmosphere to make the amorphous Si film 32 a polycrystalline Si film 41 having a large grain size (FIG. 3C). There is also a method of annealing at 800 ° C. for 10 minutes, but in order to obtain a polycrystalline Si film having a large grain size, annealing at low temperature for a long time is preferable because the nucleation rate becomes smaller. Next, this polycrystalline Si film 41
Then, phosphorus is ion-implanted at 7 × 10 ¹⁵ cm ^-2 and 30 KeV (FIG. 3D). Next, a WSi _2.8 film 34, which is a mixture of W and Si, is formed to a thickness of 150 nm at 450 ° C. by using WF ₆ gas and SiH ₄ gas by the low pressure CVD method (FIG. 3E). When heat treatment for alloying the WSi _2.8 film 34 to form a tungsten silicide film, F in the WSi _2.8 film 34 diffuses in the polycrystalline Si film 41. Has a large grain size, the number of crystal grain boundaries is small and the amount of F that can be diffused is reduced. As a result, the amount of F penetrating into the gate oxide film is reduced, and the increase in the thickness of the gate oxide film is reduced. After the heat treatment, the gate electrode is formed by patterning by a known method.

By the method of the second embodiment described above, the same effect as that of the first embodiment was obtained. Next, a third embodiment of the method for manufacturing a semiconductor device of the present invention will be described with reference to FIG.
FIG. 4 is a cross-sectional view showing a step of manufacturing a gate electrode of a MOS transistor by the method of manufacturing a semiconductor device according to the present invention. 9 is formed on the Si substrate 11 by using a well-known thermal oxidation method.
A gate oxide film 31 having a thickness of 10 nm is formed at 00 ° C. (FIG. 4A). The gate oxide film 31 may be formed by using the low pressure CVD method. Next, a low pressure CVD method is used to form Si.
Amorphous Si film 32 at 550 ° C. using H ₄ gas
To a thickness of 150 nm (FIG. 4B). The formation of the amorphous Si film 32 is performed by using Si ₂ H ₆ gas.
You may perform at 80 degreeC. Next, phosphorus is ion-implanted into the amorphous Si film 32 at 7 × 10 ¹⁵ cm ⁻² and 30 KeV (FIG. 4C). Next, in an N ₂ gas atmosphere, 800
Annealing is performed at 10 ° C. for 10 minutes to form the amorphous Si film 32 into a large-grain polycrystalline Si film 41 (FIG. 4D). next,
Low pressure CVD method using WF ₆ gas and SiH ₄ gas 4
A WSi _2.8 film 34 having a thickness of 150 nm is formed at 50 ° C. (FIG. 4E). Next, a heat treatment for alloying the WSi _2.8 film 34 to form a tungsten silicide film is performed, and thereafter, patterning is performed by a known method to form a gate electrode.

By the method of the third embodiment described above, the same effect can be obtained with the same operation as the second embodiment. Next, FIG.
A fourth embodiment of the method for manufacturing a semiconductor device of the present invention will be described with reference to FIG. FIG. 5 is a cross-sectional view showing the steps of the method for manufacturing the semiconductor device of this embodiment.

The gate electrode 5 of the polycide structure of this embodiment
0 is formed in the film forming process by the CVD method. First, Si
A Si ₂ H ₆ gas of 20 cc / min was flowed on the gate oxide film 31 made of SiO ₂ formed on the substrate 11 to thermally decompose (450 ° C. to 480 ° C.) the film thickness 15
A partially amorphous Si film 51 of 00Å is formed (FIG. 5A). Next, this partially amorphized S
Phosphorus is ion-implanted into the i film 51 at 7 × 10 ¹⁵ cm ⁻² and 30 KeV (FIG. 5B). Next, on this partially amorphized Si film 51, a WSi _2.8 film 52 having a film thickness of 1500Å is formed at about 450 ° C. by using WF ₆ gas and SiH ₄ gas.
Are formed (FIG. 5C). Next, the semiconductor device having the partially amorphized Si film 51 and the WSi _2.8 film 52 is heat-treated at about 900 ° C. to form the tungsten silicide film 53 and the partially amorphized Si film 51 is crystallized. To form a polycrystalline Si film 54 (FIG. 5D). Next, the polycrystalline Si film 54 and the tungsten silicide film 53 are etched into a predetermined shape to form a gate electrode 50 having a polycide structure (FIG. 5E). In addition, in order to further enhance the effect of the partially amorphized Si film, 200
It is advisable to employ a process in which a low temperature heat treatment is performed in the temperature range of ℃ to 500 ℃ for 10 to 30 minutes and then the temperature is raised to 900 ℃. The low temperature heat treatment may be performed in the temperature range of 600 ° C to 650 ° C for about 2 hours to 10 hours. By this low-temperature heat treatment, amorphous Si has a larger grain size
There is an advantage that it becomes an i film and F diffusion is further reduced.

Conventionally, polycrystalline Si is formed on the gate oxide film 31.
In order to form a film, F easily diffused through the grain boundaries of the polycrystalline Si film and entered the gate oxide film 31 in the heat treatment step after the WSi _x film 52 was formed. Since the polycrystalline Si film 54 having a large grain size is formed on the film 31, there are few crystal grain boundaries in which F can easily diffuse, and the amount of F entering the gate oxide film 31 is suppressed. As a result, oxygen-free SiO ₂ bond is turned off is rarely caused by F that has entered the gate oxide film 31 made of SiO _2. Therefore, the free oxygen reacts with the Si in the Si substrate 11 and the Si in the partially amorphized Si film 51 to form SiO ₂ and the gate oxide film 1 is formed.
2 is prevented from increasing, and the gate capacitance is prevented from decreasing due to the increase in the thickness of the gate oxide film 31. In addition, the increase in dangling bonds due to the breaking of the SiO ₂ bond is prevented, and the gate breakdown voltage is prevented from decreasing. As a result, the device characteristics as designed were obtained.

Next, a fifth embodiment of the present invention will be described with reference to FIG. FIG. 6 is a cross-sectional view showing the steps of the fifth embodiment of the method of manufacturing a semiconductor device having a polycide structure. The gate electrode 60 having the polycide structure of this embodiment is also formed in the film forming process by the CVD method. First, on the gate oxide film 31 made of SiO ₂ formed on the Si substrate 11,
By thermally decomposing SiH ₄ (620 ℃), the film thickness becomes 80
A 0Å polycrystalline Si film 61 is formed (FIG. 6A). Next, on the polycrystalline Si film 61, Si ₂ H ₆ is added to 20c.
Partly amorphized Si film 6 with a film thickness of 700 Å by flowing c / min and thermally decomposing (450 ° C to 480 ° C)
2 is formed (FIG. 6B). Next, a WSi _2.8 film 63 having a film thickness of 1500Å is formed on the partially amorphized Si film 62 by using WF ₆ gas and SiH ₄ gas at about 450 ° C. (FIG. 6C). Next, the semiconductor device manufactured in the above process is heat-treated at about 900 ° C. to crystallize the WSi _2.8 film 63 to form a tungsten silicide film 64 and partially amorphized S.
The i film 62 is crystallized to form a polycrystalline Si film 65 (see FIG. 6).
(D)). Next, the polycrystalline Si films 61 and 65 and the tungsten silicide film 64 are etched into a predetermined shape to form a gate electrode 60 having a polycide structure (FIG. 6E).

Also in this embodiment, the WF used in the step of forming the WSi _2.8 film 63 is the same as the other embodiments.
_Since there is no crystal grain boundary where F in ₆ gas can easily diffuse, the amount of F entering the gate oxide film 31 is suppressed. As a result,
Similar to the first embodiment, the reduction of the gate capacitance and the deterioration of the gate breakdown voltage are prevented, whereby the device characteristics as designed can be obtained.

Although the thickness of the partially amorphized Si film is 700 Å in the sixth embodiment, the thickness of the partially amorphized Si film in the subsequent step is appropriately selected, for example, 500 to 1000 Å. Selected by range.

[0025]

As described above, according to the semiconductor device of the present invention, a part or all of the structure of the polycrystalline Si film has a columnar structure extending in the film thickness direction, and moreover, the vertical cross section of the polycrystalline Si film. The grain boundary spacing seen from the direction is
Since the grain size is larger than the film thickness of the film, the grain boundary diffusion of F can be reduced as compared with the conventional polycrystalline Si film.

In the method for manufacturing a semiconductor device of the present invention, a polycrystalline Si film having a large grain size and few crystal grain boundaries or a partially amorphized Si film is formed in advance to form a WSi _2.8 film. F in the WF ₆ gas used in forming the melting point metal silicide film and F in the refractory metal silicide film cannot easily diffuse into the polycrystalline Si film. As a result, there is almost no increase in the thickness of the gate oxide film, the reduction of the gate capacitance and the deterioration of the gate breakdown voltage are prevented, and the device characteristics as designed can be obtained.

[Brief description of drawings]

FIG. 1 is a sectional view showing an example of a semiconductor device having a polycide structure of the present invention.

FIG. 2 is a cross-sectional view showing the process of the first embodiment of the method for manufacturing a semiconductor device of the present invention.

FIG. 3 is a cross-sectional view showing the process of the second embodiment of the method of manufacturing a semiconductor device of the present invention.

FIG. 4 is a cross-sectional view showing the process of the third embodiment of the method of manufacturing a semiconductor device of the present invention.

FIG. 5 is a cross-sectional view showing the process of the fourth embodiment of the method of manufacturing a semiconductor device of the present invention.

FIG. 6 is a cross-sectional view showing the steps of the fifth embodiment of the method of manufacturing a semiconductor device of the present invention.

FIG. 7 is a cross-sectional view showing a conventional process of forming a gate electrode having a polycide structure.

[Explanation of symbols]

11 Si substrate 12, 31 Gate oxide film 14 WSi _x film 21, 33, 41 Polycrystalline Si film 32, 51, 62 Partially amorphized Si film 34, 52, 63 WSi _2.8 film 24, 53, 64 Tungsten silicide film 50,60 Polycide structure gate electrode

Claims (8)

[Claims] 1. A semiconductor device having a polycide structure comprising a polycrystalline Si film and a refractory metal silicide film formed on the polycrystalline Si film, wherein the polycrystalline Si film is one of the polycrystalline Si films. Part or all of the structure has a columnar structure extending in the film thickness direction, and has a crystal structure in which the grain boundary spacing seen from the vertical cross-sectional direction of the polycrystalline Si film is equal to or more than the film thickness of the polycrystalline Si film. Characteristic semiconductor device. 2. The semiconductor device according to claim 1, wherein the refractory metal silicide film is a tungsten silicide film. 3. A method of manufacturing a semiconductor device having a polycide structure, wherein an oxide film is formed on a substrate of the semiconductor device, an amorphous Si film is formed on the oxide film, and a polycrystalline film is formed on the amorphous Si film. A Si film is formed, impurities for forming the amorphous Si film and the polycrystalline Si film as electrodes are implanted into the polycrystalline Si film, and a refractory metal is deposited on the polycrystalline Si film into which the impurities are implanted. A method of manufacturing a semiconductor device, which comprises forming a polycide structure by forming a silicide film. 4. A method of manufacturing a semiconductor device having a polycide structure, wherein an oxide film is formed on a substrate of the semiconductor device, an amorphous Si film is formed on the oxide film, and the substrate on which the amorphous Si film is formed. Is heat-treated to form at least a part of the amorphous Si film into a polycrystalline Si film, and impurities for making the polycrystalline Si film into an electrode are implanted into the polycrystalline Si film. A method of manufacturing a semiconductor device, comprising forming a polycide structure by forming a refractory metal silicide film on a crystalline Si film. 5. A method of manufacturing a semiconductor device having a polycide structure, wherein an oxide film is formed on a substrate of the semiconductor device, an amorphous Si film is formed on the oxide film, and the amorphous Si film is formed on the amorphous Si film. Impurities for making the film into an electrode are implanted, and the substrate on which the amorphous Si film is formed is heat-treated to form at least a part of the amorphous Si film into a polycrystalline Si film, and a high melting point is formed on the polycrystalline Si film. A method of manufacturing a semiconductor device, comprising forming a polycide structure by forming a metal silicide film. 6. A method of manufacturing a semiconductor device having a polycide structure, wherein an oxide film is formed on a substrate of the semiconductor device, an amorphous Si film is formed on the oxide film, and an amorphous Si film is formed on the amorphous Si film. A semiconductor characterized in that a polycide structure is formed by forming a film made of a refractory metal and Si, heat-treating a substrate on which the film made of the refractory metal and Si is formed, and forming a refractory metal silicide film. Device manufacturing method. 7. The method of manufacturing a semiconductor device according to claim 3, wherein the refractory metal silicide film is a tungsten silicide film. 8. A polycrystalline Si film is formed on the oxide film instead of the step of forming the amorphous Si film on the oxide film, and an amorphous Si film is formed on the polycrystalline Si film. The method for manufacturing a semiconductor device according to claim 3, 4, 5, or 6.